Which determinants should be considered to reduce social inequalities in paediatric dental care access? A cross-sectional study in France.

Better access to dental care through systemic and educational strategies is needed to lessen the burden of disease due to severe early caries. Our study aims to describe family characteristics associated with severe early caries: parental knowledge, attitudes, practices in oral health and socio-demographic factors. For this cross-sectional study, 102 parents of children aged under 6 years with severe early caries and attending paediatric dentistry service in France completed a questionnaire during face-to-face interviews. Caries were diagnosed clinically by calibrated investigators, using the American Academy of Paediatric Dentistry criteria, and dental status was recorded using the decayed, missing, and filled teeth index. The majority of children were from underprivileged backgrounds and had poor oral health status, with a median dmft index of 10. Parents highlighted the difficulty of finding suitable dental care in private practices. Parents appeared to have good oral health knowledge and engaged in adapted behaviours but showed a low sense of self-efficacy. They perceived the severity of early caries as important but the susceptibility of their child as moderate. The study affirmed the importance of improving the accessibility of paediatric dental care and developing educational strategies to enhance the knowledge, skills, and oral health practices of families.

Introduction

Severe early childhood caries (S-ECC) is defined as any sign of smooth-surface caries in a child younger than 3 years; and from ages 3 through 5, one or more cavitated, missing due to caries, or filled smooth surfaces in primary maxillary anterior teeth; or a decayed, missing, or filled score of greater than or equal to four (age 3), greater than or equal to five (age 4), or greater than or equal to six (age 5) [1]. The prevalence of S-ECC varies, depending on countries and studies, but it has been estimated between 21% and 41.2% [2-4]. It increases steadily with the child’s age: 17% when the child is one year old, 36% when 2, 43% when 3, 55% when 4, and 63% when 5 [5]. The disease has individual consequences for children, their family, and community and is considered a major public health problem worldwide [6]. It mainly affects children from underprivileged backgrounds [7].

Patient management usually consists of dental care, under nitrous oxide sedation or general anaesthesia, performed by paediatric dentists. In France, paediatric dental care is insufficient and unevenly distributed [8-10]. In addition, the demand for care exceeds the availability, causing significant waiting times that, in turn, worsen children’s health condition. In disadvantaged groups characterized by low socio-economic status, low literacy level (i.e. a person’s capacity to obtain, process, and understand basic health information and services needed to make appropriate health decisions [11]), and less frequent use of care, S-ECC is highly recurrent and can become a chronic disease [12-14]. Prevention strategies have led to a decrease in the dmft (decayed-missing-filled tooth) index [15,16], but since they do not take into account barriers to dental care (e.g. literacy, oral health knowledge) or dental access (e.g. numerical, geographical, and financial accessibility, especially for patients with partial or no social coverage), they are not sufficient to reach the most affected population groups. The current strategies contribute to increasing social inequalities in oral health [6].

Levesque et al. proposed a conceptual framework for healthcare access (Fig 1) describing determinants of demand and supply [17]. In this model, the knowledge, attitudes, and practices in oral health and the socio-demographic characteristics of families are determinants of access to paediatric dental care. There has been no study exploring these determinants in France. Our study aims to describe the knowledge, attitudes, practices, and socio-demographic characteristics of families of children with severe early caries to identify strategies for improving access to care and reducing social inequalities in oral health.

Fig 1

A conceptual framework of access to health care.

Levesque proposed a model of the determinants of access to health care [17].

Methods

Study design, population, and ethics

This cross-sectional study with a prospective recruitment was conducted following the Strengthening the Reporting of Observational studies in Epidemiology (STROBE) statements. A total of 102 parents of children with severe early caries attending the paediatric dentistry department of Lille University Hospital for treatment participated in the study. The sample represents the Haut-de-France region. The French Personal Protection Committee approved the study, and the protocol was recorded on ClinicalTrials.gov (Identifier: NCT04195607). A Participant Information Sheet was provided, and a written consent from all participants was obtained prior to their inclusion in the study.

Participants were selected according criteria, between November 2019 and October 2020 at Lille University Hospital (North of France), Odontology Service, Pole of Medical and Surgical Specialties, Functional Unit of Paediatric Dentistry. Each child patient must be affiliated with France’s social security insurance. Children who are not affiliated with social security insurance, have a person taking care of them daily who is not their mother or father, and who do fulfill the following conditions will not be included in the study: (i) they have a serious medical condition (such as leukemia …), and/or (ii) their parents do not speak French. Each patient can be included only once in the study (they may be included in the study at either the point of initial treatment or relapse, but not both). Families selected for the study will be questioned in the presence of the patient, on the day of their consultation, and in one of the hospital’s consulting rooms. Patients who fulfil the inclusion criteria and are willing to consult will be selected for study until the required number of subjects is met. Children will be selected after they have had a clinical examination validating a diagnosis of severe early caries. A child can be included in the study at any point in their course of treatment, including before, during, or after treatment. The study consists of two steps: (1) clinical examination of the child and (2) interview of the parent.

Diagnosis and clinical examination of the child

The clinical examination is a usual procedure. Children were examined by the principal investigator or by calibrated examiners (inter-rater reliability k = 0.89; mean intra-rater reliability k = 0.97) in the presence of one of their parents. Examiners used an examination tray consisting of a mirror, a probe, tweezers, and pads. According to the definition of the American Academy of Paediatric Dentistry (AAPD), children with S-ECC were included. The dmft index was used to record caries for each primary tooth present [18]. The teeth were examined under the operating light after drying them with a pad to determine the dmft index.

Parent interview

Data on family predictors were collected using a structured questionnaire developed by the researcher (TM) based on the literature [19]. The questionnaire was written in French and explored two types of variables: quantitative and qualitative. The questionnaire was piloted in a non-target sample of three parents of children with S-ECC. The formulation of certain questions were later modified.

The participants completed the questionnaire during a face-to-face interview with the investigator who performed the clinical examination. Interviews were conducted in a consulting room of the hospital.

The questionnaire consisted of three sections with a total of 34 items. The first section concerns the child’s medical history (i.e. presence of disease or use of medication) and oral health practices (i.e. frequency of brushing and its supervision by an adult, frequency of food intake, consumption of sweet foods, drinks consumed during meals and during the day) and the parent’s dental history (i.e. dental health, dental treatment) and tobacco use. The second section is about the family’s socio-demographic characteristics (i.e. child’s age and country of birth; mother and father’s age, country of birth, educational level, last employment, occupational status, and marital status; number of people living at home; number of children in the family; siblings; social benefits). The investigator then obtained their health insurance information and asked the reason for consultation, the avoidance of dental care (for the parent and for the child), and the importance of the cost of dental care. In the third section, we explored parents’ oral health knowledge and attitudes (i.e. locus of control, sense of self-efficacy, perceived importance of oral health-related behaviours, and characteristics of oral health belief model) [19]. Finally, we determined parental oral health literacy level through a single question which is “How often do you need someone to help you when reading instructions, leaflets, or other written documents” [20].

Statistical analysis

Continuous variables were expressed as means (±standard deviation, SD) in the case of normal distribution or medians (interquartile range, IQR) otherwise. Normality of distribution was assessed using histograms and the Shapiro-Wilk test. Categorical variables were expressed as numbers (percentage). Association of dmft index with the presence of an associated disease was tested using Mann-Whitney U test and the association of dmft index with child’s age was tested using Spearman’s rank correlation coefficient. Comparisons in child’s characteristics according with the frequency of a tooth brushing at least twice a day were performed using Chi-square tests (or Fisher’ exact tests when expected cell frequency was <5) except for child’s age where a Mann-Whitney U test was used.

Statistical testing was done at the two-tailed α level of 0.05. Data were analyzed using the SAS software package, release 9.4 (SAS Institute, Cary, NC, USA).

Results

Socio-demographic characteristics of the family and parental oral health literacy level

Table 1 show the socio-demographic characteristics of the study participants. Of the 102 children, 57 (55.9%) were boys. The majority of children (95.1%, N = 97) were born in France. Mean age was 4.0 years (± 1.1). Most children (77.5%, N = 79) were accompanied by their mother, while 19.6% (N = 20) were accompanied by their father. The mothers’ mean age weas 33.5 years (± 6.6). Among mothers, 71.6% (N = 73) were born in France and 74.5% (N = 76) had a level of education less than or equivalent to a bachelor’s degree. Regarding their last employment, 43.1% of mothers were employees (N = 44), while 40.2% had no profession (N = 41). Stay-at-home mothers comprised 54.6% (N = 56), whereas 37.3% of mothers were employed (N = 38). In contrast, the fathers’ mean age was 37.1 years (± 8.0). The majority of fathers (66.3%, N = 67) were born in France, and 76.3% (N = 77) had a level of education less than or equivalent to a bachelor’s degree. Regarding their last employment, 40.6% were blue-collar workers (N = 41), and 30.7% were employees (N = 31). Most fathers (83.2%, N = 84) were engaged in professional activity. Among parents, 79.4% (N = 81) were married or in a similar relationship, while 16.7% (N = 17) were divorced or separated. Regarding the number of children in the family, 34.3% (N = 35) of families have two children (including half-brother and half-sister), 30.4% (N = 31) have three children, 39.2% (N = 40) have four children, while 23.5% (N = 24) have five children staying in the same home. Among children with severe early caries, 35.3% (N = 36) were the first child, 23.5% (N = 24) were the second child, and 22.5% (N = 23) the third child in the family. Notably, 54% of the families received social aid (i.e. children and housing). To determine parental oral health literacy level, the parents were asked the question, “How often do you need someone to help you when reading instructions, leaflets, or other written documents from your doctor or pharmacy?”, to which 56.9% (N = 58) answered never, 16.7% (N = 17) almost never, 20.6% (N = 21) sometimes, 2.9% (N = 3) often, and 2.9% (N = 3) always.

Table 1

Socio-demographic characteristics of the family, health status and oral health practices of the child.

	Variable	Category	N = 102a
Socio-demographic characteristics of the child	Child gender, Males		57 (55,9)
	Child country of birth	France	97 (95,1)
		Outside the France	5 (4,9)
	Child age	<2 years	3 (2,9)
		<3 years	11 (10,8)
		<4 years	12 (11,8)
		<5 years	34 (33,3)
		<6 years	42 (41,2)
		Mean age (± SD)	4,0 (±1,1)
	Accompanying person	Father	20 (19,6)
		Mother	79 (77,5)
		Other	3 (2,9)
	Parents marital status	Married or civil partnership or cohabiting	81 (79,4)
		Divorced or separated	17 (16,7)
		Single	4 (3,9)
	Number of children	1	15 (14,7)
		2	35 (34,3)
		3	31 (30,4)
		> 3	21 (20,6)
	Place in the siblings	1st	36 (35,3)
		2nd	24 (23,5)
		3rd	23 (22,6)
		4th and beyond	19 (18,6)
	Number of people living at home	2	6 (5,9)
		3	14 (13,7)
		4	40 (39,2)
		5	24 (23,5)
		6 and more	18 (17,7)
Socio-demographic characteristics of the parents			Mother (N = 102)a	Father (N = 101)a
	Country of birth	France	73 (71,6)	67 (66,3)
		Outside the France	29 (28,4)	34 (33,7)
	Educational level	No diploma	10 (9,8)	10 (9,9)
		Certificate of general education	14 (13,7)	14 (13,8)
		Certificate of professional competence or equivalent	20 (19,6)	31 (30,7)
		Bachelor’s degree or equivalent	32 (31,4)	22 (21,8)
		2 years after bachelor	11 (10,8)	11 (10,9)
		Higher diploma	15 (14,7)	13 (12,9)
		Last employment	Farmer	0 (0)	0 (0)
	Craftsman, shopkeeper or entrepreneur		1 (1,0)	8 (7,9)
	Senior executive or higher intellectual profession		7 (6,9)	8 (7,9)
	Intermediate profession		6 (5,9)	4 (4,0)
	Employee		44 (43,1)	31 (30,7)
	Worker		3 (2,9)	41 (40,6)
	Without profession		41 (40,2)	9 (8,9)
	Occupational status	Employed	38 (37,2)	84 (83,1)
		Student or apprenticeship	1 (1,0)	0 (0)
		Unemployed	5 (4,9)	11 (10,9)
		Retired	0 (0)	2 (2,0)
		Stay-at-home parent	56 (54,9)	0 (0)
		Another situation	2 (2,0)	4 (4,0)
	Social benefits		54 (52,9)
	Dental status, medical history, and oral health practices of the child				N = 102a
Smooth surfaces		Decayed		87 (85,3)
Primary maxillary anterior teeth attacked		Decayed, filled or missing (caries)		92 (90,2)
Disease		Long-term disease		12 (11,8)
		Asthma		6 (5,9)
		Gastroesophageal reflux		2 (2,0)
Tooth brushing		At least once a day		86 (84,3)
		Morning before breakfast		13 (15,1)
		Morning after breakfast		61 (71,8)
		Noon		11 (12,9)
		Evening before dinner		3 (3,5)
		Evening after dinner		79 (91,9)
		Supervised oral hygiene		68 (66,7)
Frequency of food intake		> 4 per day		75 (73,5)
		Daily sweet foods		94 (92,2)
		Sweet foods once a day		25 (26,7)
Sweet food		Sweet foods twice a day		38 (40,4)
		Sweet foods three times		18 (19,1)
		Sweet foods four times a day or more		13 (13,8)
Main drinks during meals		Tap water		6 (5,9)
		Bottled water		72 (71,3)
		Soda		4 (4,0)
		Fruit juice		8 (7,9)
		Other	Fruit syrup	10 (9,9)
			Milk	1 (1)
Sweet drinks		Daily sweet drinks:		64 (62,7)
		-Sweet drinks once a day		25 (39,1)
		-Sweet drinks twice a day		20 (31,2)
		-Sweet drinks three times		5 (7,8)
		-Sweet drinks four times a day or more		14 (21,9)

aValues are expressed as numbers (percentage).

These results provide in the first part the socio-demographic characteristics and concern the gender, the country of birth and the age of the child with severe early caries. They also specify the relationship with the carer, the marital status of the parents, the number of children in the family, the place of the child with severe early caries in the siblings and finally the number of people living in the same household. The second part describe the socio-demographic characteristics of the parents and concern their country of birth, their education level, their last employment, their occupational status and their perception of social benefits. The last part provide informations firstly on severe early caries (number of smooth surfaces decayed, primary maxillary anterior teeth attacked), secondly on the child medical history (in particular: long-term disease, asthma or gastroesophageal reflux). Then, these results expose oral health practices: frequency of tooth brushing, frequency of consumption of sweet foods, sweet drinks and the main drinks consumed during meals.

Dental status, medical history, and oral health practices

Table 1 shows the children’s dental status, medical history, and oral health practices (e.g. brushing and feeding). Notably, 11.8% of the children (N = 12) had a pathology, and 7.8% (N = 8) had long-term treatment. Of the 102 children median dmft index was 10 (interquartile range 8 to 13). Analysis of the dmft index according to the child’s age gives us a median dmft index of 8 at 1 year, 10 at 3 years, and 11 at 5 years. A positive significant correlation was found between child’s age and dmft index (r = 0.23, p = 0.019). Dmft index was not significantly associated with the presence of an associated disease (median with pathology 9 (IQR, 8 to 10.5), without 11 (IQR, 8 to 14), p = 0.22).

Among parents, 84.3% (N = 86) reported brushing the teeth of their child at least once a day, with 71.8% (N = 61) doing so in the morning after breakfast, and 91.9% (N = 79) doing so in the evening before bedtime. 93.3% (N = 42) of girls have at least one tooth brushing compared to 77.2% (N = 44) of boys (p = 0.026). Children with at least one tooth brushing (N = 86) are on median 4 years old, as those without tooth brushing (N = 16) (p = 0.23). Most parents (66.7%, N = 68) supervised their child’s tooth brushing. Regarding food intake, 73.5% of children (N = 75) eat more than four times a day, and 92.2% (N = 94) eat sweet food (e.g. pastries, chocolate bars, etc.) daily. While 77.3% of parents (N = 78) indicated that their child drinks water during mealtime, 62.7% (N = 64) reported that their child consumes sugary drinks daily. 83% of children who consume sweet foods on a daily basis have at least one tooth brushing compared to 100% for those who do not consume (p = 0.35). 80% of children who eat more than 4 times a day have at least one tooth brushing compared to 96.3% who do not eat more than 4 times a day (p = 0.063).

Oral health knowledge, attitudes and behavior

Parental oral health knowledge is summarized in Table 2. Only 20% of the parents interviewed appeared to have poor oral health knowledge, but majority of them do not know about fluoride or its role in dental care. Parental oral health self-efficacy which is the belief that the parent has in his or her ability to perform a task is summarized in Table 3. Notably, 31% of parents had a positive sense of self-efficacy, that is, they strongly agree or agree with the implementation of behaviours adapted to their child’s oral health. Parental oral health behaviours are presented in Table 4 where 81% of parents agree with good oral health behaviours. Most parents (64.7%, N = 66) thought that they are responsible for the presence of early childhood caries (i.e. internal locus of control), while 35.3% (N = 36) thought that the occurrence of the disease was not under their control (i.e. external locus of control). The majority of parents (71%) considered engaging in favourable behaviours to promote their child’s oral health (e.g. checking their child’s mouth regularly, brushing twice a day with fluoride toothpaste, going to the dentist regularly, avoiding sweet foods and drinks even at night) of high importance. Characteristics concerning the health belief model are summarized in Table 5. Perceived susceptibility was tempered; in fact, 53% of parents thought that most children have dental caries. The severity of the disease was perceived as important for the child’s health, with 93,1% of parents agreeing with the statement “Dental problems can be serious for a child”. Barriers to oral health behaviours were perceived as low, but 55.9% of parents thought that “It is difficult to prevent [their] child from eating or drinking sweet foods”. Nevertheless, the parents believed that the perceived benefits of positive oral health behaviours are important.

Table 2

Parental oral health knowledge.

Statement	Truea	Falsea	I don’t knowa
A child can brush his teeth alone at 4	44 (43,1)	58 (56,9)	0
A child needs to have his first dental visit at 6	28 (27,5)	74 (72,5)	0
Child teeth need to be brushed once a day	14 (13,7)	88 (86,3)	0
Temporary teeth are not important	5 (4,9)	93 (91,2)	4 (3,9)
There is no need to go to the dentist unless the child has a problem	10 (9,8)	90 (88,2)	2 (2,0)
Fluoride toothpaste is better to brush child teeth	53 (52,0)	32 (31,35)	17 (16,65)
Bacteria cause caries	82 (80,4)	16 (15,7)	4 (3,9)

aValues are expressed as numbers (percentage).

These results provide informations about the parental oral health knowledge through two sets of questions. Parents were asked to answer true, false or I don’t know to the first 7 questions on basic knowledge. To the next 7 questions on knowledge of oral health behaviours, they answered good, bad, neither good nor bad or I don’t know.

Table 3

Parental oral health self-efficacy.

Statement	Strongly disagreea	Disagreea	Neutrala	Agreea	Strongly agreea	I don’t knowa
You check your child’s teeth and gum carefully every month	6 (5,9)	5 (4,9)	22 (21,6)	23 (22,5)	46 (45,1)	0
You regularly take your child the dentist for check-up	6 (5,9)	8 (7,8)	15 (14,7)	18 (17,6)	55 (53,9)	0
You use fluoridated toothpaste for your child	12 (11,8)	7 (6,9)	15 (14,7)	9 (8,8)	41 (40,2)	18 (17,6)
Your child doesn’t take anything except water after brushing his teeth and before going to sleep	22 (21,6)	8 (7,8)	7 (6,9)	5 (4,9)	60 (58,8)	0
You prevent your child from frequently eating sweets	15 (14,7)	8 (7,8)	15 (14,7)	19 (18,6)	45 (44,1)	0
You prevent your child from putting something that has been in someone else’s mouth into their own	5 (4,9)	4 (3,9)	5 (4,9)	12 (11,8)	76 (74,5)	0
Fluoride varnish has already been applied to the teeth of your child	66 (64,7)	4 (3,9)	4 (3,9)	3 (2,9)	9 (8,8)	16 (15,7)
You prevent your child from drinking sodas	16 (15,7)	12 (11,8)	11 (10,8)	22 (21,6)	41 (40,2)	0
You avoid putting your child to bed with a sweet bottle	12 (11,8)	5 (4,9)	3 (2,9)	9 (8,8)	72 (70,6)	1 (1,0)
Teeth of your child are brushed twice a day	17 (16,7)	8 (7,8)	11 (10,8)	15 (14,7)	51 (50,0)	0

aValues are expressed as numbers (percentage).

These results provide informations on parental self-efficacy in oral health through a set of 10 questions whose answers are based on a Likert scale.

Table 4

Parental oral health behaviors.

Statement	Uselessa	Usefula	I don’t knowa
Take your child for a dentist for check-up or cleaning	2 (2,0)	100 (98,0)	0
Take the child for his first visit before a year	75 (73,5)	26 (25,5)	1 (1,0)
Brush the child’s teeth twice a day or more	4 (3,9)	98 (96,1)	0
Brush your teeth twice a day or more	6 (5,9)	96 (94,1)	0
Help children brush their teeth when they are under 6	4 (3,9)	98 (96,1)	0
Eat sweets less than once a day	20 (19,6)	82 (80,4)	0
Consume sugary drinks less than once a day	20 (19,6)	82 (80,4)	0
Use fluoride toothpaste for the child	24 (23,5)	60 (58,8)	18 (17,6)
Do not eat or drink (anything other than water) after brushing teeth and before going bed	5 (4,9)	97 (95,1)	0

aValues are expressed as numbers (percentage).

These results provide informations on parental oral health behaviors through a set of 9 questions to which parents answer useful, useless or I don’t know.

Table 5

Parental oral health belief model.

Statement	Strongly disagree	Disagree	Neutral	Agree	Strongly agree	I don’t know
Most of children have dental caries	9 (8,8)	15 (14,7)	22 (21,6)	26 (25,5)	28 (27,5)	2 (2,0)
Your child will have caries in the next few years	15 (14,7)	31 (30,4)	18 (17,6)	29 (28,4)	8 (7,8)	1 (1,0)
My child can have a carie as soon as his first tooth has erupted	34 (33,3)	16 (15,7)	14 (13,7)	16 (15,7)	20 (19,6)	2 (2,0)
It is unlikely that my child will have problems with his teeth	21 (20,6)	32 (31,4)	20 (19,6)	20 (19,6)	9 (7,8)	1 (1,0)
Dental problems can be serious for a child	0	1 (1,0)	5 (4,9)	10 (9,8)	85 (83,3)	1 (1,0)
Having bad teeth affect child’s daily life	61 (59,8)	27 (26,5)	2 (2,0)	4 (3,9)	8 (7,8)	0
Dental problems are not as important as other health problems	74 (72,5)	19 (18,6)	3 (2,9)	5 (4,9)	1 (1,0)	0
It is difficult to take my child for the dentist for regular check-up	46 (45,1)	19 (18,6)	7 (6,9)	17 (16,7)	13 (12,7)	0
It is difficult to prevent my child from eating or drinking sweet foods	14 (13,7)	20 (19,6)	11 (10,8)	21 (20,6)	34 (33,3)	2 (2,0)
I don’t have any problem making sure my child’s teeth are brushed before he goes to sleep	15 (14,7)	12 (11,8)	7 (6,9)	19 (18,6)	47 (46,1)	2 (2,0)
It is a problem for my child to have fluoride varnish on his teeth	27 (26,5)	18 (17,6)	14 (13,7)	1 (1,0)	4 (3,9)	38 (37,3)
I don’t have any problem making sure my child’s teeth are brushed with fluoride toothpaste twice a day	7 (6,9)	12 (11,8)	16 (15,7)	19 (18,6)	33 (32,4)	15 (14,7)
It is unlikely that my child will have caries if their teeth are brushed with fluoride toothpaste twice a day	15 (14,7)	28 (27,5)	12 (11,8)	25 (24,5)	11 (10,8)	11 (10,8)
It is unlikely that my child will have caries if he goes to the dentist for regular check-up	15 (14,7)	18 (17,6)	12 (11,8)	33 (32,4)	23 (22,5)	1 (1,0)
It is unlikely that my child will have caries if I stop him from eating lots of sweet foods	8 (7,8)	16 (15,7)	17 (16,7)	28 (27,5)	33 (32,4)	0
It is unlikely that my child will have caries if an adult helps him brush their teeth until he is 6	12 (11,8)	21 (20,6)	12 (11,8)	32 (31,4)	25 (24,5)	0
It is unlikely that my child will have caries if the dentist puts fluoride varnish on his teeth	8 (7,8)	12 (11,8)	26 (25,5)	11 (10,8)	6 (5,9)	39 (38,2)

aValues are expressed as numbers (percentage).

These results focus on the oral health belief model which is studied through a set of 17 questions where parents are asked, on a Likert scale, to what extent they agree or disagree with the following statements.

Paediatric dental care and parent’s dental history

Characteristics related to paediatric dental care are shown in Table 6. Of the 102 families, 40.2% (N = 41) lived more than 30 minutes away from the service provider that takes care of their child. Most parents (79.4%, N = 81) previously consulted with dentists in private practice but were not satisfied with the care their child received; in fact, 35.8% (N = 29) had visited two or more dentists. Among parents, 43.1% (N = 44) reported that it is difficult to find suitable dental care for their young child. Notably, 64.7% (N = 66) of children were directly referred by their private dentist, 8% (N = 8) were referred by their doctor, while 23% went to the hospital spontaneously with their parent or upon the advice of a friend, a paediatrician, or a family doctor. Concerning the avoidance of care, 26.5% of parents (N = 27) already renounced dental care for themselves, with 33.3% (N = 9) giving the high cost of care as the main reason. Twenty-eight parents (27.5%) indicated that the cost of dental care is the main barrier to getting treatment for themselves, while 11 (10.8%) reported the same for their child. The majority of parents (93.1%, N = 95) stated that they never gave up dental care for their child, with 95.1% (N = 97) admitting that they have no difficulty paying for medication or health services for their family. Regarding health insurance, 51% (N = 52) had a universal health insurance and a private supplementary insurance, 43.1% (N = 44) had a universal health insurance and a solidarity supplementary insurance (i.e. French social benefits providing access to care, reimbursement of care, or medicines to any person residing in France who is not already covered by another compulsory health coverage), while 3,9% (N = 4) had a universal health insurance only without supplementary health insurance.

Table 6

The characteristics of the use of pediatric dental care.

Variable	Category	N = 102a
Distance from home to Hospital (minutes)	< 10	16 (15,7)
	< 20	28 (27,5)
	< 30	17 (16,7)
	< 40	19 (18,6)
	< 50	9 (8,8)
	< 60	6 (5,85)
	> 60	7 (6,85)
Number of dentists previously consulted (concerning people who consulted in private)	1	52 (64,15)
	2	17 (20,95)
	3 and more	12 (14,9)
Person motivating the visit	Pediatrician or family doctor	8 (8,0)
	Private dentist	66 (64,7)
	The parent himself/a friend	23 (23,0)
Reasons for avoidance of care (concerning people who renounces care)		Parents (N = 27)	Child (N = 7)
	Cost of care	9 (33,3)	3 (42,9)
	Anxiety	8 (29,6)	2 (28,6)
	Care consideration	7 (25,9)	1 (14,25)
	Patient’s refusal	2 (7,5)	0
	Transports	1 (3,7)	1 (14,25)

aValues are expressed as numbers (percentage).

These results concern the use of paediatric dental care: The distance between the place of care and the home, the number of dentists previously consulted, the person who motivated the visit, the reasons for having renounced care previously (for the child or the parent).

More than half of parents (52.9%, N = 54) considered their dental condition as good, 12.7% (N = 13) very good, 27.5% (N = 28) bad, and 6.9% (N = 7) very bad. Notably, 90.2% (N = 92) indicated that they already have a dental problem (e.g. tooth decay, gum disease), 94.1% (N = 96) have had dental care, 23.5% (N = 24) have already used a dental emergency service for themselves, and 42.2% (N = 43) have had a dental abscess. Regarding their last visit to a dentist, 39.2% (N = 40) went to a dentist in the last six months, 29.4% (N = 30) in the last year, 14.7% (N = 15) more than a year ago, and 16.7% (N = 17) more than three years ago. Among parents, 34.3% (N = 35) reported smoking.

Discussion

In this cross-sectional study, we aimed to describe the determinants to paediatric dental care access, following Levesque et al.’s model, as represented by structural determinants (e.g. sociodemographic characteristics, availability of dental care) and individual determinants (e.g. parents’ oral health knowledge, attitudes, and practices). There has been no previous study that explored all these determinants in France. Among children, attitudes and health‐related practices are established through primary socialization, while health‐related behaviours are adopted and learned from caregivers [21]. To promote children’s oral health, caregivers need to have suitable knowledge, acquire specific skills, and establish health‐oriented practices [22]. Parents also need to have a sufficient level of literacy for them to navigate the health system.

S-ECC as a marker of inequalities

Firstly, we highlighted findings regarding S-ECC. The average age of children in this study was 4 years old, which is the same as in Tinanoff’s study [5]. This can be linked to the fact that children between 0 and 3 years old with severe early caries are difficult to care for and that the majority of parents bring their children to the dentist when they are between 4 and 5 years old. Concerning gender, our results align with Peltzer’s study–boys are more affected by caries than girls (i.e. 57 versus 45) [23]. The mean dmft score (10.4 ± 4.0) in our study is higher than other studies on S-ECC (9.1 ± 3.35 in Romania [24], 8.17 ± 2.94 in China [4], and 1.01 ± 2.37 in India [3]). The dfmt index increases with the child’s age, which is in line with Tinanoff’s study. Among children, 11.8% had an associated pathology and 7.8% had long-term treatment. Although these values are lower than those in other studies [25,26], long-term medication is a risk factor for developing early caries. According to a retrospective cohort study conducted in Taiwan, children with asthma and receiving medications had higher dental caries prevalence and higher rate of severe caries than children without asthma [27]. In our study, having a long-term disease does not seem to increase the caries score in children. One possible explanation for these results is that in children with long-term disease, even if the risk is higher, parents could have more preventive oral health behaviours to avoid decompensating their pathology. The majority of children (77.5%) in our study were accompanied by their mother–a finding similar to a study conducted in Korea [28]. This could be explained by the fact that there are more mothers than fathers without a profession. Among the parents we interviewed, 28.4% of mothers and 33.7% of fathers were born outside France. According to Östberg, having a foreign-born parent is one of the main risk factors for dental caries [29]. People of foreign origin consult less because access to care is more difficult, particularly because of the language barrier. In our study and in previous studies, low family socio-economic level was associated with dental caries in children [30]. We also found that the majority of parents have a low level of education, with 74.5% of mothers and 76.3% of fathers having a level of education less than or equivalent to a bachelor’s degree. Notably, 56% of mothers stay at home, while 83.2% of fathers are employed, mainly as blue-collar workers, and 54% of parents receive social benefits. These data match with earlier works [4,23,31], affirming that early childhood caries is a marker of social inequalities [7]. To ensure equity in access to oral healthcare, we must strengthen oral health promotion and education at different stages of a child’s life and target vulnerable populations. Moreover, it is necessary to address barriers to healthcare access, particularly structural determinants.

Structural explanations to consider

Secondly, we proposed structural explanations regarding access to paediatric dental care. The parents’ care pathway is difficult, and they consult too late because of long waiting times. The diagnosis of S-ECC is not made by the family doctor but by a dentist with whom parents do not consult early enough. After the diagnosis, the recourse to specialized structures is complex. In fact, 79.4% of children were not taken into care in private offices or were not treated in private practice due to the unavailability of a specialized paediatric dentist or the inability of general dentists to treat very young children. In our study, 64.7% of children were directly referred by their private dentist. In France, many dentists do not cover care for people from underprivileged backgrounds who only have solidarity supplementary insurance [32]; hence, they are referred to hospitals where waiting times are long. Delaying care can consequently cause complications for children [33,34]. In our study, 40.2% of families live more than 30 minutes away from the hospital that takes care of their child, and this makes dental check-ups challenging. Difficulties related to access to paediatric dental care emerge as the main barriers explaining severe early caries [2]. For 43.1% of families, it was difficult to find a dentist to care for their child, and this underlines the need for sufficient and efficient care to avoid caries relapse. Concerning the renunciation of care, 26.5% of parents already renounced dental care for themselves, with 33.3% stating the high cost of care as the main reason. For 27.5% of parents, the cost of dental care is a barrier to getting treatment for themselves, while 10.8% reported the same for their child even though only 3,9% reported not having supplementary insurance. It is difficult for these parents to avail of specialized procedures (e.g. nitrous oxide sedation) because these are expensive and often not covered in private offices. Although dental insurance can be considered as a lever for patients to seek care, in France, almost all patients have health insurance (public and private) covering the costs of the main dental treatments. If patients pay the cost of care, other reasons may explain the non-use of dental care, for example, dental anxiety [35]. Overall, this financial barrier, which is linked to supplementary health insurance, is less significant than main obstacle–insufficient health care provision (e.g. specialized paediatric dentist).

The role of individual components

Finally, the study focused on individual explanations. The majority (80%) of parents have a good knowledge of oral health, but they do not know much about fluoride. Regarding the statement “It is better to use fluoride toothpaste when brushing children’s teeth”, only 52% of parents answered “true”, while only 42% agreed with the statement “Protecting child’s teeth with fluoride”. These findings are consistent with those BaniHani et al.’s study [36], and affirms that parents’ knowledge remains theoretical and not operational. This should be highlighted because using fluoride toothpaste is one of the most effective ways to prevent early caries in children. The AAPD 2008 recommends that the age of the first consultation should be no later than 1 year; however, in our study, only 27.5% of the parents interviewed thought that this is necessary. This finding is in line with those of previous studies: Higher knowledge does not necessarily translate to greater adherence with recommended oral health behaviours or improved oral health outcomes among children [37]. In our study, only 31% of parents had a positive sense of self-efficacy. As a behavioural determinant, self-efficacy reflects the extent to which a person feels capable of engaging in recommended health behaviours [38]. Self-efficacy is a predictor of maternal oral health behaviours and children’s oral health outcomes (e.g. dmft) [39]. This shows that knowledge is a central element, but it must be transformed into skills and actions to promote children’s health. Regarding parental health literacy level, more than half of parents stated that they never needed help with reading written documents from their doctor or pharmacy. Nevertheless, it is necessary to consider interventions to empower families and increase their level of literacy to facilitate access to healthcare structures (e.g. understanding how they work and resolving barriers to access). According to Chi, oral health educational interventions can improve self-efficacy [40], but these should be culturally and linguistically tailored [41]. In our study, only 19% of parents do not believe in good oral health behaviours, which is an interesting finding because parents play an important role in the oral health of their children and are the primary decision-makers regarding health and health-related behaviours. Notably, 64.7% of parents reported having an internal locus of control. According to Albino, who conducted a research among American Indians, children who have parents with an internal locus of control have smaller increases in dmft over the course of a prevention program than those whose parents have an external locus of control [42]. The majority of parents (71%) believed that it is important to engage in good oral health behaviours, although this was not enough to implement them since behaviour change is a complex matter. Oral health is conditioned by belief. According to Wilson, mothers with higher oral health knowledge perceive greater benefits from adherence to recommended oral health behaviours and have greater confidence in their ability to manage their children’s oral health [39].

Most parents (66%) considered their oral health to be positive (i.e. either good or very good). Children whose parents feel that their health is poor are 3.9 times more likely to develop ECC [43]. In fact, 90.2% of parents in our study indicated that they already have a dental problem. According to Roberts et al., children who have caregivers with tooth loss have significantly greater caries prevalence than those whose caregivers have no tooth loss [44]. Mothers who have high levels of untreated caries are more than three times as likely to have children who have an increasing extent of caries experience [45]. In our study, 14.7% of parents had their last dental consult more than a year ago, while 16.7% had one more than three years ago. According to Bozorgmehr, there is no significant relationship between parents’ and children’s frequency of dental visits [46]. Notably, many parents generally prioritize their child’s health over theirs for whatever reason. In our study, only 23.5% of parents have used a dental emergency service for themselves.

Concerning oral health practices for their chil, 84.3% of parents reported brushing at least once a day; this percentage is higher than that in a study conducted in Taiwan where 61% of children with S-ECC had at least one daily brushing [47]. Although brushing twice a day is recommended, frequency of brushing has not been validated as an indicator of early caries, according to Nobile et al. [31]. In our study, 66.7% of parents reported supervising their child when toothbrushing. Studies have highlighted the link between lack of brushing supervision and the development of early caries [4,48,49]. Our study is in agreement with the literature which shows that girls generally have more positive oral health behaviours, however the gap remains limited with the boys [50]. According to Murthy, for children under 6 years old, toothbrushing should be performed by parents [51]. In addition to advising children to start toothbrushing at a very early age, parents should be advised to supervise them until they are at least 6 years old. Regarding food intake, 73.5% of children in our study eat more than four times a day, and this is in line with a previous study published in 2013, indicating that children with S-ECC eat more than five times a day (5.26 ± 1.64) [52]. Most children (92.2%) eat sweet foods daily. Daily consumption of sweet foods has been associated with early caries between 1 and 2 years of age, especially when it exceeds 10% of the recommended energy intake [53,54]. While 77.32% of parents indicated that their child consumes water during mealtime, 62.7% stated that their child consumes sugary drinks daily. This is consistent with the literature [55], but the percentage in our study is less than that in a previous study conducted in China where 76 to 82% of children who drink sweetened drinks daily developed early childhood caries [56]. Our study found that children who eat sweet foods more than four times a day brush their teeth more frequently. However, according to a study carried out in a French adolescent population, positive eating behaviours are associated with more frequent brushing [57]. Our results could be explained by the fact that in our very young population, parents who have less control over their children’s eating practices would be more involved in brushing their teeth, with the objective of limiting dental caries progression.

Perspectives

Like any cross-sectional study, our study has limitations. Our small sample consisted of children diagnosed with S-ECC in a regional hospital centre. While the representativeness may be discussed, it is necessary to keep in mind that in France young children with severe early caries are not treated in private practices, thus the Hospital is the first place of recourses for dental care. Nevertheless, the findings cannot be generalised to the entire paediatric population. In addition, we used a questionnaire that may be affected by response bias due to social desirability. Another factor that may cause response bias is that parents who have consulted before in private practices may have received prevention information. It would be interesting to know the origin of parents’ oral health knowledge (social media, doctor, dentist…).

We conclude that our referral activity in paediatric dental care confirms a public health problem, mainly related to the access to care. We identified two types of determinants: structural (e.g. lack of specialized paediatric dentists in private practices and lack of preventive measures to avoid the disease) and individual (e.g. need to improve parental operational knowledge and skills, attitudes, practices, and literacy). Clinicians can address individual determinants by using strategies, such as therapeutic patient education. However, structural measures are required to address structural determinants and enhance dental care accessibility, ensure primary and tertiary prevention, and improve treatment.

6 May 2021

PONE-D-21-12152

Which determinants should be considered to reduce social inequalities in paediatric dental care access?  A cross-sectional study in France.

PLOS ONE

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5. Review Comments to the Author

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Reviewer #1: The study aims to describe family characteristics associated with severe early caries, based on a clinical evaluation of 102 children whose parents were interviewed. The topic seems original, insofar as it is the first study to our knowledge with such a design, and as the topic is of interest.

Some comments should however be addressed:

Introduction

1) L.55-56 : « The prevalence of S-EEC varies, … between 21% and 41.2% ». Is this regardless to age ? Are there differences in children of 3 or 6 year old ?

2) L.60 : « in France, paediatric dental care is insufficient and unevenly distributed ». Do you have a reference for this statement ?

3) L.65 : « Prevention strategies have led to a decrease in the dmft index ». Do you have a reference for this statement ? Or is it reference 5 ?

Methods

1) L.85 : « the sample represents the Haut-de-France region ». It is unclear how it is representative ? To what extent can you affirm that it is representative ?

2) L.90-97 : Although we understand the global design of the study, I think authors should be clearer in the conduct of the study, precisely (1) children : clinical examination / (2) parents : interview. In the method section, it is sometimes unclear who we are talking about : parent or child ?

3) L.112 : what if both parents accompanied their child ? How did you choose, if you have made a choice ?

4) L.121-122 : « asked the renouncement », « asked the effect of the cost of dental care ». I think these should be rephrased.

5) L.125 : although the « single question » appears in the results section, I think authors should mention this question here in the methods section.

Results

1) L.174 : authors set a threshold at « at least once a day » for the toothbrushing frequency. Why once ? Recommendations are of a twice a day brushing, it would have been relevant to have a « twice a day » line, which could have allowed a comparison with previous national studies (e.g. Fernandez de Grado G. et al. Plos One, 2021).

2) Table 3 : « sweet food > 4 per day : 75 ». Some lines further « sweet foods four times a day or more : 13 ». I think the first line refers to the eating frequency rather than the sweet food intake ?

3) L.195 : there is a unsollicited parenthesis after « health »

4) Table 5 : 1st statement : before going « to » bed

5) In general, and for better clarity, is it possible to bring together some tables ?

Discussion

1) I think there shoud be subheadings in the discussion section, which would lead to a much more comfortabel reading.

2) L.277 : is the term « caregiver » correct ? I think authors are speaking of parents. It is confusing how parents are caregivers, and authors should not lead to any misunderstanding between parents or nurses / dentists / other therapists.

3) L.285 : 8.5±3.82 versus 9.1±3.35 in Romania : why « versus » ? To what is the first value compared ?

4) L.286-287 : « 7.8% had a long-term treatment … is a risk for developing early caries ». Authors seem to have the data to make a comparison between children with or without long-term treatment regarding their dmft index. It would be interesting to have an idea if there is a significant higher dmft index in this study ?

5) L.289 : « 28.4% of mothers and 33.7% of fathers were born in France ». In table 2, these values refer to « born outside of France ». Is there a mistake in line 289 ?

6) L.306 : is the reference 25 accurate ? « In France, many dentists do not cover car for people from underprivileged backgrounds… », but ref. 25 deals with Italy.

7) L.308 : with reference 27, another reference would be relevant regarding the consequences linked to delaying care : North S. et al. J Paediatr Dent, 2007 17 :105-9

8) L.319-321 : considering the results showed at lines 250-255, is there really a financial barrier, or is it rather a musunderstanding or a lack of understanding/knowledge about the healthcare system and its possibilities ?

9) L.354 : again, the word « caregivers » is confusing. Are you speaking of the parents ?

10) L.361 : « 84.3% of parents reported brushing at least once a day » : for themselves or for their children ?

11) L. 368-371 : it would be interesting to established a parallel with these associated factors and the frequency of a toothbrushing at least twice a day, since it is also associated to food intake, perceived family wealth, etc. See Fernandez de Grado G. et al. Plos One, 2021.

12) L.376-379 : « may not be generalizable » : this joins my previous comment (introductiotn section, comment 1). It would have been interesting to compare these results with those of a control group. Is there a reason why no such comparison was conducted ?

13) L.383 : « need to improve parental knowledge ». The study showed that the knowledge would not be that bad. The key point in my opinion is to find a way to upgrade skills/practices in relation to knowledge.

In general, authors should be attentive to the concordance of times. Frequently, past times are mixed with sentences in the present time (l.114, l.147, l.176-179, …). Please have a second reading of the whole manuscript.

Reviewer #2: Dear author,

This study, although interesting, deserves some clarification in the event of publication.

First of all, and it is mentioned in your discussion, this study is not representative of a population, neither geographically nor an age group. Its sample is too limited. Its main selection bias is to be a sample of children referred by the private dentist, probably not all children with severe early caries.

Please specify clearly including or excluding criteria (serious medical conditions?).

Please specify which analytical statistics tests have enabled you to confirm the elements of your discussion, and show the P value for each one.

In socioeconomic factors, have you studied the monthly household budget in example? Or the influence of place of life (city vs country...). Have you been able to determine which level of parental education gives the child the greatest risk? From the mother? from father? both? Is there a correlation? Too much "According to..." in the discussion. Why didn't you use Liskert scale in table 4?

For the oral part, which part of children use a toothbrush zero or one time a day? You wrote "sense of self-efficacy 31%". Do you mean that parents believe in doing the right things for their child?At the end of the consultation, did you proceed to an oral health education session, and if so, did you see the child again to validate the changes in belief and ability?

The analysis of oral health beliefs is very interesting and well done.

In my opinion, the discussion should be revised by specifying that it is a descriptive study on a small sample, not representative of the French population or of the age group studied. I would prefer that analytical statistics come to validate the assertions of the discussion.

Sincerely yours

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18 Jun 2021

A response letter has been uploaded previously. Its contents are given below.

--

Dear Reviewers,

On behalf of all authors, I would like to thank you for the time you spent providing constructive comments on this article.

We have made the corrections, modifications, and revisions that you have requested to improve the manuscript. We also responded to your comments, the details of which you will find in the attached pages. We believe that the study is now much stronger and clearer as a result of your review.

We hope you enjoy reading it.

Yours sincerely,

Thomas MARQUILLIER

General comments

The authors mentioned that the study protocol is currently being published in BMJ Open. The revised manuscript has been submitted

The authors reformatted this manuscript to follow the journal's guidelines.

The authors used a professional service (Scribbr) to check language use in the manuscript.

The authors proceeded to a deposition within data repository in ZENODO (indexed in OpenAIRE).

DOI: 10.5281/zenodo.4948448

Reviewers’ comments

Comments to the Author

1. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Yes

Reviewer #2: Partly

2. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: N/A

Reviewer #2: No

The suggested analyses and the tests used have been added.

3. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: Yes

Reviewer #2: Yes

The authors proceeded to a deposition within data repository in ZENODO (indexed in OpenAIRE).

DOI: 10.5281/zenodo.4948448

4. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: Yes

Reviewer #2: Yes

The authors used a professional service (Scribbr) to check language use in the manuscript.

5. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: The study aims to describe family characteristics associated with severe early caries, based on a clinical evaluation of 102 children whose parents were interviewed. The topic seems original, insofar as it is the first study to our knowledge with such a design, and as the topic is of interest.

Some comments should, however, be addressed:

Introduction

1) L.55-56: « The prevalence of S-EEC varies, … between 21% and 41.2% ». Is this regardless of age? Are there differences in children of 3 or 6 years old?

As indicated in the manuscript, the prevalence of S-EEC depends on the country, the studies, and the age of the child. The older the child is, the higher is the prevalence, and the more the pathology is expressed. This is logical since the eruption of teeth follows an order: As the child grows, they develop more teeth that can be affected by the condition.

According to Tinanoff, “Finding from these 72 reports that the mean caries prevalence for 1-year-olds was 17%, and greatly increased to 36% in 2-year-olds. Additionally, the 3-, 4-, and 5-year-olds’ mean caries prevalence were 43%, 55%, and 63%, respectively.”

The authors have made this clarification in the manuscript.

We found a positive significant correlation between child’s age and dmft index (r = 0.23, p = 0.019). Analysis of the dmft score according to the child's age generated a median dmft score of 8 at 1 year, 10 at 3 years, and 11 at 5 years. These results are in line with the literature.

2) L.60: « in France, paediatric dental care is insufficient and unevenly distributed ». Do you have a reference for this statement?

Paediatric dentistry is not an officially recognised speciality in France, so it is difficult to provide an exact distribution. Nevertheless, three references affirm the fact that paediatric dental care is unevenly distributed and is insufficient in number in France.

We added the following references to support our assertion:

� Muller-Bolla M, Clauss F, Davit-Béal T, Manière MC, Sixou JL, Vital S. Oral and dental care for children and adolescents in France. Le Chirurgien-Dentiste de France. 2018;1806–1807.

� Dominici G, Muller-Bolla M. Activity of private « paediatric » dentists in France. Rev Francoph Odontol Pediatr. 2017;4(12):152–158.

� Fock-king M, Muller-Bolla M. Analysis of the growing demand for paediatric dentistry treatment in hospitals. Clinic. 2018;39:411–17.

3) L.65: « Prevention strategies have led to a decrease in the dmft index ». Do you have a reference for this statemen? Or is it reference 5?

This statement is supported not only by reference 5 but also by the two references below:

� Abhishek M. Comprehensive review of caries assessment systems developed over the last decade. RSBO. 2012;9(3):316–21.

� Frazao P. Epidemiology of dental caries: When structure and context matter. Braz Oral Res. 2012;26(1):108–14.

Methods

1) L.85: « The sample represents the Haut-de-France region ». It is unclear how it is representative? To what extent can you affirm that it is representative?

The representativeness of the patient population of a university hospital is indisputable since it is the only place where patients in the region seek care. The provision and the standard of care in private practices are difficult to access and dissuasive for these patients. The study thus aims to improve the quality of the service offered in the region by adding an adapted educational component to improve the knowledge and skills of this specific population. The representativeness seems to be in line with expected practices at a regional level.

The goal is to study a specific group of affected children to illustrate a practical reality, so it is a proxy measure. Severely affected children show recurrence of caries, which necessitate the implementation of an educational programme that addresses the needs of this population.

2) L.90-97: Although we understand the global design of the study, I think authors should be clearer in the conduct of the study, precisely (1) children : clinical examination / (2) parents : interview.

The authors have clarified this point.

In the methods section, it is sometimes unclear who we are talking about: parent or child?

The authors have clarified this in the methods section.

3) L.112: What if both parents accompanied their child? How did you choose, if you have made a choice?

In general, only one parent is allowed to accompany the child in the paediatric care area. It is assumed that the parent accompanying the child is the one who cares for the child the most, knows the child the best, and reassures the child when needed, and is thus the parent who is most willing to answer questions.

4) L.121-122: « asked the renouncement », « asked the effect of the cost of dental care ». I think these should be rephrased.

The sentence has been reworded.

5) L.125: Although the « single question » appears in the results section, I think authors should mention this question here in the methods section.

The question has been added in the methods section.

Results

1) L.174: Authors set a threshold at « at least once a day » for the toothbrushing frequency. Why once? Recommendations are twice a day brushing; it would have been relevant to have a « twice a day » line, which could have allowed a comparison with previous national studies (e.g. Fernandez de Grado G. et al. Plos One, 2021).

This is true; however, in very young children, especially those from low-income backgrounds who are severely affected by tooth decay, oral hygiene is generally absent. We assumed that proper brushing at least once a day with fluoride toothpaste and under parental supervision is already an important first step for these children. The time of brushing (i.e. evening before bedtime) and parental supervision are here studied in preference to the frequency of brushing performed. At the start of the study, the parameter ‘brushing twice a day’ was to be recorded, but after testing the questionnaire, the item was adapted to fit the reality and to avoid overloading the already dense questionnaire.

2) Table 3: « sweet food > 4 per day : 75 ». Some lines further « sweet foods four times a day or more : 13 ». I think the first line refers to the eating frequency rather than the sweet food intake?

This is correct. Revision has been made: 75% is the frequency of food intake, and 13 is the frequency of sweet food intake.

3) L.195: There is an unsolicited parenthesis after « health »

This has been corrected.

4) Table 5: 1st statement : before going « to » bed

This has been corrected.

5) In general, and for better clarity, is it possible to bring together some tables?

Thank you for your comment. The authors have bring together some tables.

Discussion

1) I think there should be subheadings in the discussion section, which would lead to a much more comfortable reading.

The authors have added subheadings to the discussion section.

2) L.277: is the term « caregiver » correct ? I think authors are speaking of parents. It is confusing how parents are caregivers, and authors should not lead to any misunderstanding between parents or nurses / dentists / other therapists.

The term “caregiver” is also used for stepfamilies and single-parent families and is a common formulation in the Anglo-Saxon literature.

3) L.285 : 8.5±3.82 versus 9.1±3.35 in Romania : why « versus » ? To what is the first value compared ?

This is an error that has been modified.

4) L.286-287: « 7.8% had a long-term treatment … is a risk for developing early caries ». Authors seem to have the data to make a comparison between children with or without long-term treatment regarding their dmft index. It would be interesting to have an idea if there is a significant higher dmft index in this study.

This is indeed an interesting comparison. In the literature, children with long-term medical conditions that necessitate medication (e.g. asthma) have a higher prevalence of dental caries (Wu FY, Liu JF. Asthma medication increases dental caries among children in Taiwan: An analysis using the National Health Insurance Research Database. J Dent Sci. 2019 Dec;14(4):413-418. doi: 10.1016/j.jds.2019.08.002.). It thus makes sense to add this comparison in the results and discussion sections.

In our sample, dmft index was not significantly associated with the presence of pathology (median with pathology 9 [IQR, 8 to 10.5], without pathology 11 [IQR, 8 to 14]; p = 0.22).

These results can be explained by the fact that despite increased risk of early caries among children with long-term pathologies, parents might have more preventive oral health behaviours to prevent the pathology.

5) L.289: « 28.4% of mothers and 33.7% of fathers were born in France ». In table 2, these values refer to « born outside of France ». Is there a mistake in line 289?

This is an error that has been modified.

6) L.306: Is reference 25 accurate? « In France, many dentists do not cover car for people from underprivileged backgrounds… », but reference 25 deals with Italy.

This is a mistake. We only kept reference 26.

7) L.308: With reference 27, another reference would be relevant regarding the consequences linked to delaying care : North S. et al. J Paediatr Dent, 2007 17 :105-9

Thank you for this suggestion. We have added this reference.

8) L.319-321: Considering the results showed at lines 250-255, is there really a financial barrier, or is it rather a misunderstanding or a lack of understanding/knowledge about the healthcare system and its possibilities?

There is indeed a lack of knowledge of the healthcare system and its possibilities on the one hand; on the other hand, the specific treatment of very young children (e.g. sedation, crowns on baby teeth, etc.) in towns requires fees that are not covered by insurance. These extra fees are common in France. People with universal health insurance and a solidarity supplementary insurance are often labelled in private practice as disadvantaged. They are reluctant to pay fees that are not covered, so there is a clear financial barrier to dental care.

9) L.354 : Again, the word « caregivers » is confusing. Are you speaking of the parents?

The term “caregiver” is also used for stepfamilies and single-parent families and is a common formulation in the Anglo-Saxon literature. It refers, in particular, to parents, but it is important not to be exclusive about the term.

10) L.361: « 84.3% of parents reported brushing at least once a day » : for themselves or for their children?

This statement has been clarified.

11) L. 368-371: It would be interesting to establish a parallel with these associated factors and the frequency of toothbrushing at least twice a day since it is also associated to food intake, perceived family wealth, etc. See Fernandez de Grado G. et al. Plos One, 2021.

Thank you for your comment. As suggested, we have added comparisons of child characteristics and frequency of toothbrushing.

Regarding gender, 93.3% of girls have at least one toothbrushing compared to 77.2% of boys (p = 0.026). Comparing these data with age, children with at least one toothbrushing and those without toothbrushing are, on mean, 4 years old (p = 0.23).

Regarding the consumption of sweet products, 83% of children who consume sweet foods on a daily basis have at least one toothbrushing compared to 100% of those who do not consume sweet foods (p = 0.35). Meanwhile, 80% of children who eat more than four times a day have at least one toothbrushing compared to 96.3% of those who do not eat more than four times a day (p = 0.063). These results have been included and discussed in the discussion section.

12) L.376-379: « may not be generalizable » : This joins my previous comment (introduction section, comment 1). It would have been interesting to compare these results with those of a control group. Is there a reason why no such comparison was conducted?

We understand and appreciate your comment and would like to provide some background regarding our thought process prior to the study. We considered conducting a case-control survey but recognised that such would be extremely difficult, as it would require matching the ethnic or social origin variable, for example. This would make it nearly impossible to find controls. In contrast, a descriptive study in a patient population without a control group is appropriate in our case. The representativeness of the patient population of a university hospital has been discussed above. Although there can be no question regarding “representativeness” in the statistical sense of the term, there may be questions at an epidemiological level in terms of Berkson’s bias. Children admitted to the hospital are those with the worst oral health, and it is necessary to identify the causes of their poor oral health to improve response and intervention. The study therefore aims to improve the quality of this service by adding an adapted educational component that addresses the needs of this specific population in the region.

13) L.383: « need to improve parental knowledge ». The study showed that the knowledge would not be that bad. The key point in my opinion is to find a way to upgrade skills/practices in relation to knowledge.

Thank you for this pertinent observation. We have made it clear that our goal is to find a way to improve the operational knowledge and skills of parents and not only their theoretical knowledge, which is already partly satisfactory.

In general, authors should be attentive to the concordance of times. Frequently, past times are mixed with sentences in the present time (l.114, l.147, l.176-179, …). Please have a second reading of the whole manuscript.

Thank you for your attention. We used a professional service to check language use in the manuscript.

Reviewer #2:

This study, although interesting, deserves some clarification in the event of publication.

First of all, and it is mentioned in your discussion, this study is not representative of a population neither geographically nor an age group.

We understand your comment and would like to provide some background to our thought process prior to the study. We considered that a case-control survey would be extremely difficult to set up as it would require matching the ethnic or social origin variable, for example. This would make it nearly impossible to find controls. By contrast, a descriptive study in a patient population without a control group—with the biases it includes—is attractive in our case. The representativeness of the patient population of a university hospital has been discussed above.

Its sample is too limited.

It is true that the sample in this study (N = 102) may seem limited at first sight. Nevertheless, the analysis in this first original study conducted in France on a population of children with early caries is mainly descriptive; therefore, it seems fitting to identify the first results. Cross-sectional studies have strengths and limitations that need to be highlighted beforehand, so you are right to point this out.

Its main selection bias is its sample of children referred by the private dentist.

The representativeness of the patient population of a university hospital is indisputable since it is the only place where patients in the region seek care. The provision and the standard of care in private practices are difficult to assess and dissuasive for these patients. Although there can be no question regarding “representativeness” in the statistical sense of the term, there may be questions at an epidemiological level in terms of Berkson’s bias. Children admitted to the hospital are those with the worst oral health, and it is necessary to identify the causes of their poor oral health to improve response and intervention. The study, therefore, aims to improve the quality of this service by adding an adapted educational component that addresses the needs this specific population in the region.

Probably not all children with severe early caries

Children with early caries are not only referred by private dentists, they also come by themselves. The hospital is the first place of recourse for these young children who are not treated by private dentists in France. The only bias is that we do not know how many children did not manage to reach the hospital.

Please specify clearly inclusion or exclusion criteria (serious medical conditions?).

This subsection has been clarified.

Please specify which analytical statistics tests have enabled you to confirm the elements of your discussion, and show the P value for each one.

We described the statistical tests used in the statistical analysis. Association of dmft index with the presence of pathology was tested using Mann-Whitney U test, while the association of dmft index with child’s age was tested using Spearman’s rank correlation coefficient. Comparisons of child characteristics and frequency of toothbrushing were performed using Chi-square tests (or Fisher’s exact tests when the expected cell frequency was <5), except for child’s age for which Mann-Whitney U test was used.

For socioeconomic factors, have you studied the monthly household budget, for example?

No, this data has not been collected directly, but it can be deduced from the parents' socio-professional category. It is difficult to collect this data in populations that are not very well off, and of what use would it be? In France, income data is difficult to collect because of differences in salaries and allowances and because of a certain degree of reticence when providing this type of information. In general, it is common practice to collect this data via the profession or deduce is from the patient’s level of social protection (e.g. the social minimum).

Or the influence of place of life (city vs country...)

This data is interesting, but it was not directly studied by choice since the survey was already cumbersome. However, we evaluated the travel time between the patient’s home and the hospital. As the hospital is located in the centre of a metropolis, it is easy to deduce the location of the participants.

Have you been able to determine which level of parental education gives the child the greatest risk? From the mother? From father? Both? Is there a correlation?

This information is not easy to determine in a cross-sectional study. It entails complex information that can be estimated by aggregating several data in a more robust study. The authors will consider this relevant remark for their future work.

Too much "According to..." in the discussion

We have reworded sentences containing this phrase.

Why didn't you use Likert scale in Table 4?

This is possible, but our questionnaire was based on the literature, which uses more true or false or do not know for the knowledge part.

For the oral part, which part of children use a toothbrush zero or one time a day?

As it is indicated that 84% of children brush their teeth at least once a day. From this data, we deduced the percentage of those who do not brush.

You wrote "sense of self-efficacy 31%". Do you mean that parents believe in doing the right things for their child?

Self-efficacy is the belief that an individual can perform a task. This has been specified in the results section.

At the end of the consultation, did you proceed to an oral health education session, and if so, did you see the child again to validate the changes in belief and ability?

No, this was not possible during the consultation, and changes would not be visible after one session. We plan to do structured educational sessions that fit the needs of the patients, which is why we set up this study in advance.

The analysis of oral health beliefs is very interesting and well done.

In my opinion, the discussion should be revised by specifying that it is a descriptive study on a small sample, not representative of the French population or of the age group studied

Thank you for your comment. We have reworded the discussion.

I would prefer that analytical statistics come to validate the assertions of the discussion.

We provided statistical clarification as mentioned above.

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15 Jul 2021

Which determinants should be considered to reduce social inequalities in paediatric dental care access?

A cross-sectional study in France.

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Reviewer #2: Dear author,

3 points maybe for next publication.First, it's not because the recruitment of patients is in a teaching hospital that this makes the population studied representative of the general population. 2nd, I maintain that it would have been interesting to specify the zero and once toothbrushing groups for future stratified analysis. Finally, don't underestimate your patients' ability to understand what you are telling them. Contrary to what you indicate in your answer, it is possible that changes in behavior are possible, and therefore that an improvement in hygiene indices would have been observable for a part of the studied population.

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23 Jul 2021

PONE-D-21-12152R1

Which determinants should be considered to reduce social inequalities in paediatric dental care access? A cross-sectional study in France

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