Effect of Acrylic Removable Partial Denture in Caries Prevalence Among Diabetic and Non-Diabetic Patients.

Background: Dental caries is the most prevalent dental disease affecting human race. The etiology and pathogenesis of dental caries are known to be multifactorial. Studies have shown that removable partial dentures in the oral cavity increases the biofilm formation and consequently an increase in the occurrence of caries and periodontal diseases. There is a complex relationship between diabetes mellitus and dental caries. Patients with diabetes are more susceptible to oral sensory, periodontal, and salivary disorders which could increase the risk of developing new and recurrent dental caries. Therefore, the aim of the study was to assess the prevalence of dental caries among diabetic and non-diabetic acrylic removable partial denture wearers. Materials and
Methods: Individuals participating in the study were partially edentulous and aged between 18 and 64 years. Patients were screened at Out patient department (OPD) in the Department of Prosthodontics JSSDCH, among which 60 patients were diabetic based on the random blood sugar level more than 160 mg/dl-30 patients were wearing RPD and 30 were without RPD. And 60 non-diabetic patients were selected among which 30 were wearing RPD and 30 without RPD. A total 120 patients were screened. Dental caries prevalence was assessed using Decayed, Missing, Filled (DMFT) index.
Results: Diabetic group unrehabilitated with removable partial prosthesis showed significant difference in the number of missing teeth when compared to non-diabetic patients without removable prosthesis (P < 0.05).
Conclusion: Removable partial denture prosthesis had less impact on prevalence of dental caries with good oral hygiene, following post insertion RPD instructions and regular dental visits irrespective of diabetes. Copyright:

INTRODUCTION

Dental caries is the most prevalent dental disease with a high morbidity potential which has made it to focus on dental health profession.[12] The etiology and pathogenesis of dental caries are known to be multifactorial. It has been found to be more severe in diabetic patients.[3] Removable partial denture and caries interrelationship studies had given contradictory statements.[4] Rania Rodan et al.[5] had stated that removable partial denture insertion into the oral cavity results in increase plaque formation on remaining tooth surface and adversely affects the periodontal status resulting in tooth mobility. It also results in accumulation of plaque especially on abutment teeth to which clasps are attached and those areas of teeth and soft tissues which are covered by the denture. Clasps, rests, and denture bases interfere with the physiologic clearance results in accumulation of food and provides a retentive area for bacterial attachment.[6] Studies had stated that plaque accumulation on tooth surface adjacent to an edentulous space is lower in the absence of RPD, RPD inhibits self-cleansing action, RPD with clasps on the other hand provides an area on abutment teeth for plaque accumulation if the individuals do not remove regularly the prosthesis.[789] It also reported that wearing RPD for a duration of about 6 months results in initiation and progression of caries.[10] Other factors such as age, physical disabilities of an individual, and poor motivation regarding the oral hygiene also aggravate the carious lesions.[4]

Research further had proven that quantitative increase of streptococcus mutans in saliva is associated with insertion of RPD resulting in increased risk of caries.[11] Streptococcus mutans and lactobacillus progression results in lowering the pH favoring an environment for the initiation and development of caries.[12]

Diabetes is a chronic metabolic disorder which affects millions of people.[13] International diabetes federation survey reported about 9.3% of the world population are diabetic at the end of 2019. The prevalence of diabetes in India has remained 11.8% at the end of 2019 according to National Diabetes and Diabetic Retinopathy survey report. Research studies had showed the impact of diabetes on oral health resulting in dental caries, periodontal disease, and tooth mobility.[14]

Poor metabolic control of diabetes results in salivary gland hypofunction, increase salivary glucose concentration which favors an environment for the progression, and development of streptococcus mutans and lactobacillus.[15] Recent studies had shown that periodontitis is directly related to increased blood glucose level in type II diabetics and uncontrolled diabetics results in severe bone loss, attachment loss, and tooth loss.[16]

Studies had revealed that diabetic patients are five times more likely to be partially edentulous than non-diabetic due to periodontal problems and tooth loss.[17] Apart from that, low socioeconomic status also influence on oral hygiene status and on number of missing tooth.[18]

Therefore, the purpose of this study was to assess the effect of acrylic removable partial denture in the prevalence of dental caries among diabetic and non-diabetic patients.

MATERIALS AND METHODS

A comparative study was carried out in JSS Dental College and Hospital, JSSAHER Mysore. Individuals participating in the study were partially edentulous and aged between 18 and 64 years, either diabetic or non-diabetic. Ethical clearance ref no JSS/DCH/Ethical/PhD-07/2017-18 and written informed consent form was taken from each of the subjects. By obtaining their consent form, their diabetic status was assessed by routine blood sugar level. Patients with random blood sugar level more than 160 mg/dl were considered as diabetic. Patients of either sex aged between 18 and 64 years with oral hygiene status 0.1 to 1.2 were considered for further evaluation. Patients of age 18 years and above are considered as young adults, so they are included in the study.

The sample size was calculated based on the assumption of confidence interval 95% and allowable error 5%. The sample size was calculated using the formula

Study design

A pilot study was conducted and a total of 120 patients were screened and broadly divided into removable partial denture prosthesis and without removable partial prosthesis group. Each group was further sub divided into two sub groups: 30 patients with diabetes and 30 without diabetes.

Types of participants

Non-diabetic and diabetic patients with sugar level more than 160 mg/dl with RPD for a minimum period of 6 months were included in the study. There should be minimum of seven teeth per arch within the flange extension area are considered. Traumatically lost tooth that are rehabilitated with RPD and patients with both the arches with RPD are considered as one sample. Teeth that are decayed and restored adjacent to the flange extension area after RPD insertion are included in the study.

Patients those who are completely edentulous, fully dentate, neuromuscular disorder, periodontally compromised, and suffering from other systemic diseases are not included in the study. Apart from those teeth that are extracted for orthodontic purposes, tooth with RPD and FPD are not considered.

The study involved completion of a predesigned and structural ethical committee approved questionnaire that was prepared to collect information regarding sociodemographic information on their profile, age, sex, income, occupation, diet, sweets intake, parafunctional and deleterious habits, awareness regarding removable partial denture usage, and satisfaction. Studies had proven that socioeconomic factors, diet, habits, and other factors contribute for initiation and progression of caries. All these factors fulfill the aims and objectives of the study. The questionnaire was designed on sociodemographic factors and hypothesis of the study. The questionnaire was standardized based on the expert's remarks fulfilling the criteria and objectives of the study. The content validity index (CVI) and cronbach's error value for the questionnaire was 0.8%. To classify individuals into different socioeconomic categories, modified BG Prasad socioeconomic scale was being used. The oral hygiene status was analyzed through direct oral examination. After oral examination, the questionnaire was filled by the examiner himself through personal interaction with the study participants to ensure uniformity in data collection and to avoid misinterpretation of the questions by the subject. Dental caries prevalence was assessed using DMFT index.

Statistical analysis

Descriptive statistics and one-way ANOVA test were used to test the significance between the variables and between the groups. Fisher's test was used to assess the statistical significance among variables within the group. A P value of 0.05 or less was considered significant. Results are presented as mean ± standard deviation. SPSS 17 software analysis was used.

Table 1 showed that decayed, filled teeth between groups does not show any statistical significance. But missing teeth showed statistical significance in diabetes mellitus without removable prosthesis group. Table 2 showed that it was statistically significant between particular group but not all the groups. Therefore, fisher's test [Table 3] was applied in which missing teeth was statistically significant in diabetes mellitus without prosthesis group when compared to non-diabetic without prosthesis.

Table 1

Statistical significance between each variable

Descriptive
	n	Mean	Std. Deviation	Std. Error
Decayed
DM wt Prost	30	3.0000	1.87083	0.51887
DM w prost	30	1.0000	1.00000	0.57735
ND wt prost	30	2.6579	2.23336	0.36230
ND w prost	30	2.9333	2.25093	0.58119
Total	30	2.7101	2.13584	0.25712
Missing
DM wt Prost	30	7.4615	3.77746	1.04768
DM w prost	30	6.0000	3.00000	1.73205
ND wt prost	30	3.9474	3.82698	0.62082
ND w prost	30	5.7333	4.66701	1.20502
Total	30	5.0870	4.14352	0.49882
Filled
DM wt Prost	30	1.8462	3.48440	0.96640
DM w prost	30	1.3333	1.52753	0.88192
ND wt prost	30	1.8158	2.02492	0.32848
ND w prost	30	2.8000	3.05193	0.78801
Total	30	2.0145	2.55811	0.30796

Table 2

Statistical significance between groups

ANOVA
	Sum of squares	df	Mean square	F	Sig.
Decayed
Between groups	10.717	3	3.572	0.775	0.512
Within groups	299.486	65	4.607
Total	310.203	68
Missing
Between groups	131.419	3	43.806	2.748	0.050
Within groups	1036.059	65	15.939
Total	1167.478	68
Filled
Between groups	12.516	3	4.172	0.627	0.600
Within groups	432.470	65	6.653
Total	444.986	68

Table 3

Statistical significance between each group

Multiple comparisons
Dependent variable: Missing LSD: Fisher’s Least Significant difference
(I) gp	(J) gp	Mean difference (I-J)	Std. error	Sig.	95% confidence interval
					Lower bound	Upper bound
DM wt prost	DM w prost	1.46154	2.55719	0.570	−3.6455	6.5686
	ND wt prost	3.51417*	1.28279	0.008	0.9523	6.0761
	ND w prost	1.72821	1.51285	0.258	−1.2932	4.7496
DM w prost	DM wt Prost	−1.46154	2.55719	0.570	−6.5686	3.6455
	ND wt prost	2.05263	2.39428	0.394	−2.7291	6.8343
	ND w prost	0.26667	2.52502	0.916	−4.7762	5.3095
ND wt prost	DM wt Prost	−3.51417*	1.28279	0.008	−6.0761	−.9523
	DM w prost	−2.05263	2.39428	0.394	−6.8343	2.7291
	ND w prost	−1.78596	1.21741	0.147	−4.2173	0.6454
ND w prost	DM wt Prost	−1.72821	1.51285	0.258	−4.7496	1.2932
	DM w prost	−.26667	2.52502	0.916	−5.3095	4.7762
	ND wt prost	1.78596	1.21741	0.147	−.6454	4.2173

*The mean difference is significant at the 0.05 level.

RESULTS

There was no significant difference between each variable in sociodemographic profile like age, sex, socioeconomic status, diet, and sweets intake. Apart from that parafunctional and deleterious habits, oral hygiene practices and removable partial denture also had less impact on decayed, missing, and filled teeth among study participants. Among diabetic group without removable partial prosthesis, significant difference was found in the number of missing teeth when compared to non-diabetic patients without removable prosthesis.

DISCUSSION

Oral health is always an enduring part of general health. Several studies have revealed an association between socioeconomic factors and oral health.[18] Many factors such as education, occupation, and income influence the socioeconomic status of an individual.[19] The socioeconomic status also influence on the quality of food intake and status of the family which directly influence the oral health.[2] Studies have revealed that variables such as age, gender, income, and diet influence the type of denture and oral hygiene status of the patients.[20] Patients with higher socioeconomic status were at lower risk for caries; however, individuals with low socioeconomic status were at a greater risk for developing dental caries.[21] As per the review, socioeconomic status of an individual also plays a vital role in prevalence of dental caries.

Removable partial denture insertion in the oral cavity alters the oral environment resulting in increase in plaque formation on the remaining natural teeth and it may adversely affect the periodontal status of an individual.[5] Authors has stated that removable partial denture has an impact on both hard and soft tissues resulting in gingival inflammation, periodontal pocket formation, tooth mobility and dental caries. It was also reported that RPD insertion changes the quantity and quality of the plaque resulting in gingival inflammation and caries initiation.[22] RPD also enhance the patients for periodontal problems in the long term with poor oral hygiene maintenance.[23] Studies had proved that there were not much difference in the pattern of periodontal disease among RPD wearer's and non-wearer.[5] Marsh reported that removable partial denture insertion results in high lactobacillus count in the saliva favoring high carious index resulting in multiple loss of teeth.[24] Individuals with diabetes are more likely to develop dental caries, gingivitis, and periodontal problems.[25] A significant correlation exists between diabetes and tooth loss in which diabetic patients are five times more likely to be partially edentulous compared to non-diabetics.[15] The ratio of diabetic and non-diabetic in urban and rural India is around 3.04% and 1.287%. Male to female ratio in urban and rural area is 2:1 and 1:1. The contributing factors resulted in the development of periodontal disease in diabetic patients are as follows: (1) non-enzymatic process to form advanced glycation end products (AGEs) causing augmented IL-1 and TNF-α secretion, (2) immunological alterations, (3) gram negative anaerobic bacteria, (4) alterations of the microcirculatory blood flow in periodontal tissues and metabolic control.[26] Patients with uncontrolled diabetes are more prone for infections, dental caries, and periodontal diseases and number of missing teeth is positively associated with it.[27] In this study, when compared to decayed and filled teeth, missing teeth in diabetic group without removable prosthesis showed highest number which is statistically significant compared to non-diabetic without removable prosthesis. As per the result, removable partial denture prosthesis impact on missing teeth was less, whereas diabetic factors can aggravate the periodontal problems resulting in loss of teeth in certain conditions. About 23.1% of individuals with diabetes had reported with more number of missing teeth when compared to non-diabetics which is about 5.3% who are unrehabilitated with RPD, which is statistically significant. Diabetic and non-diabetic patients who are rehabilitated with RPD reported 33.3% and 6.7%, respectively, decayed tooth. Among filled tooth, diabetic patients with RPD are about 33.3% and non-diabetic are 20%. Even though it showed statistical significance within the groups, it is not significant between the groups. Therefore, it shows that RPD has impact on prevalence of dental caries and diabetic conditions favor an environment for the progression of dental caries. Studies had revealed that even though RPD has an impact on prevalence of dental caries, it had less effect on periodontal disease.[28] Hannon 1955 and Carlsson 1965 with thorough follow-up study stated that caries lesion located on the tooth surface were not in contact with removable partial denture, even though RPD facilitates plaque retention. These findings support that RPD has less intervention in caries initiation and progression.[29] Addy and Bates' study mentioned that continuous wearers of RPD effects plaque accumulation when compared to day time wearers.[30] Mustafa Demirci et al.[31] reported that age, family size, and socioeconomic position plays a role in caries prevalence. In this study, socioeconomic status had no impact on prevalence of dental caries. Diabetes must be meticulous with their home care to control periodontal disease.[32]

CONCLUSION

Within the limitations of the study, removable partial denture had effect on prevalence of dental caries. Following post insertion RPD instructions and regular follow-up appointments reduce the prevalence of dental caries. Furthermore, there also appears to be a high risk for dental caries in the RPD wearers in the absence of good oral hygiene measures. Diabetes mellitus which could be the additional factor affecting the periodontal health of an individual under certain conditions had a major impact on missing teeth irrespective of removable partial denture prosthesis. Therefore, further research should be carried out regarding factors influencing on prevalence of dental caries and missing and filled teeth in the presence of removable partial denture prosthesis and diabetic condition.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.