Nigerian dentists' knowledge of aggressive periodontitis.

OBJECTIVE: To assess the general knowledge of Nigerian dentists on aggressive periodontitis (AgP) and specific knowledge of distinguishing between the clinical features of localized aggressive periodontitis (LAP) and generalized aggressive periodontitis (GAP).
MATERIALS AND METHODS: A cross-sectional, non-random convenience survey was done on 200 dentists, in three geopolitical zones of Nigeria, using pre-tested, closed question- type questionnaires. Eventually, only 133 questionnaires were analyzed. Relationships between six outcome variables namely clinical features of LAP, clinical features of GAP, LAP oral hygiene, GAP oral hygiene, laser therapy option and type of laser therapy, and the explanatory variables of gender and experience were analyzed.
RESULTS: A total of 33.8% of the dentists had poor general knowledge, 16.5% had fair knowledge, 31.9% had good knowledge, while 10.5% had excellent knowledge. Gender- and experience-related differences were found, but they were not statistically significant.
CONCLUSION: Both the general and specific knowledge of aggressive periodontitis among Nigerian dentists is less than expected and needs improvement through targeted, continuing dental education.

INTRODUCTION

Aggressive periodontitis (AgP) is the rapid destruction of periodontal tissues and is related mainly to Aggregatibacter actinomycetemcomitans. Its prevalence ranges from 0.13% in Tehran[1] through 0.6% in Turkey,[2] and an unusually high 38.4% in a closely-knit Israeli community.[3] Reported prevalence of aggressive periodontitis in Nigeria ranges between 0.8[4] through 1%[5] and 1.56%.[6]

Concerned Nigerian authors have pointed to the late presentation of Nigerian AgP patients, as these patients have presented between the ages of 18 and 30 years in a Lagos study.[7] Dosunmu and co-workers also raised an alarm about the ‘very late’ presentation of patients in Ibadan-Nigeria, as also the accompanying psychological depression.[8]

As a prelude to the current study, as per the experience of the authors, nine patients (aged 14, 19, 20, 20, 21, 25, 31, 33, and 37 years) presented at the specialist periodontal clinic of a teaching hospital within six months. Their ages were clearly above those commonly quoted in literature and the level of periodontal destruction and psychological depression was a great cause of concern.

Suggestions to tackle the late presentation of cases include, ‘early diagnosis of juvenile periodontitis and regular check-ups,’[7] while psychotherapy has been advocated as an adjunct to prosthetic and periodontal rehabilitation.[8] The problem, however, is that some of the nine patients seen in one of the study centers reported previous dental visits where extractions had been performed without proper management of AgP.

Given this background, the authors sought to evaluate the reasons for late presentation of patients with AgP in Nigeria. The authors hypothesized two possible explanations. First, that the patients lacked dental awareness, and therefore, did not present themselves for treatment, and second, that late presentations actually represented cases of missed opportunities, predicated on the fact that many Nigerian dentists had forgotten the basic diagnosis and treatment of AgP.

The present study, therefore, represents an attempt to evaluate the knowledge of Nigerian dentists about basic age-related prevalence, clinical features, diagnosis, and treatment of aggressive periodontitis. It is intended that the results of this pilot survey will form an objective assessment of the training needs of Nigerian dentists in the area of aggressive periodontitis.

MATERIALS AND METHODS

Ethics

The study was carried out in accordance with the declaration of Helsinki. Consent was taken as agreement to fill the questionnaires, which contained no personal identifiable responses. The questionnaires were distributed at several events outside institutional boundaries, therefore, institutional clearance was neither sought nor considered necessary. However, the committee on dental education and practice of the Nigerian Dental Association granted permission for the studies.

Sampling and setting

A cross-sectional, non-random, convenience sampling was adopted for this study. The sample size of 133 was, therefore, completely based on convenience, but was considered adequate being a pilot survey in the teaching hospitals in two geo-political zones of Nigeria. Th choice of the hospitals was based entirely on the location of the researchers.

Dentists attending continuing dental education events of the Nigerian Dental Association were also included in the study, which accounts for the few numbers of dentists working outside the teaching hospitals where the researchers work.

Study instrument

To test the hypotheses, dentists were given about 200 self-administered pre-tested questionnaires. Of this about 150 questionnaires were filled and returned giving a response rate of 75%. Of this number, only 133 were eventually evaluated due to grossly incomplete entries in some of the forms.

Six knowledge assessment areas captured in the questionnaire included clinical features of LAP, clinical features of GAP, LAP oral hygiene (OH), GAP oral hygiene, laser therapy option, and type of laser therapy. The diagnostic criteria were the involvement of the central incisors and third molars only (LAP) and at least three other permanent teeth. This was in consonance of the consensus report on the classification of periodontal diseases.[9] These formed the outcome variables evaluated in relationship with three explanatory variables namely gender and years of experience.

All questions were closed and multiple choice-type, except the questions about year of graduation and specific type of laser therapies applicable to AgP. The expected answer for laser therapy applicable to periodontitis was diode laser.

Statistical analyses

After data cleaning, 133 questionnaires were analyzed using the Predictive Analytic SoftWare (PASW) (formerly SPSS)[10] statistical software. Basic analyses of the frequencies of various responses were performed. The outcome variables were: The knowledge of the teeth involved in LAP and GAP, the oral hygiene differences between both entities, and offering of orthodontic treatment where drifting was evident, among others.

The explanatory variables were gender and years of professional experience recoded for meaningful statistical analyses into Group 1 (one to five years post qualification) and Group 2 (six years and above).

Cross-tabulations of outcome and explanatory variables were performed to study the relationship between the variables, using the Chi-squared statistic at 95% confidence level. Analyses yielding P < 0.05 were, therefore, considered statistically significant.

In all instances where participants failed to respond to certain questions, the analyses were based only on the number of valid responses. This means that figures in the results did not always sum up to 133. Explanatory footnotes were inserted in such instances.

Knowledge was analyzed in two phases. Phase one was an assessment of general knowledge of AgP based on a slight modification of the Ethiopian University Education knowledge scoring system as adapted by Medhanyie et al.[11] Thus, 80% or more was classified as excellent knowledge, 61 - 79% as good knowledge, 46 - 60% as fair knowledge, and 45% or less as poor knowledge.

Phase two was an assessment of specific knowledge in relation to the six explanatory variables relating to specific knowledge of clinical features and treatment of LAP and GAP.

RESULTS

There were 133 participating dentists (82 males, 51 females) with different years of professional experience. Sixty-one participants graduated within the previous five years, 63 graduated at least six years previously, while nine respondents declined to state their years of graduation.

When filtered according to general knowledge of the six evaluated aspects of AgP, 45 (33.8%) of the respondents had poor knowledge, 22 (16.5%) had fair knowledge, 52 (31.9%) had good knowledge, and 14 (10.5%) had excellent knowledge.

On assessment on specific knowledge of the different aspects of AgP, 118 (88.7%) of the respondents had experience of AgP management, with over 70% accurately identifying the teeth involved in LAP/GAP and over 60% having knowledge of the oral hygiene status in LAP/GAP.

In sharp contrast, the knowledge of laser therapy was almost completely unknown among the respondents, with just over 20% being aware of this treatment option and an even smaller, 1.5%, accurately identifying the correct laser therapy applicable to aggressive periodontitis [Table 1].

Table 1

The overall knowledge of the respondents

Although male respondents demonstrated a higher knowledge of all evaluated variables, except in the correct identification of teeth involved in LAP, the observed differences failed to attain statistical significance. (P > 0.05). However, male superiority in the knowledge of disjunctive laser application in the management of AgP almost approached a statistical significance, but just failed to attain it (P = 0.056) [Tables 2 and 3].

Table 2

The specific knowledge of respondents by gender

Table 3

The specific knowledge of respondents by gender

The same knowledge pattern was demonstrated when the respondents were filtered according to years of post-qualification experience, with younger doctors demonstrating greater knowledge in all aspects, except in the knowledge of laser application in the management of AgP. However, again, all observed differences failed to attain statistical significance (P > 0.05) [Table 4].

Table 4

The knowledge of respondents by experience

DISCUSSION

Considering the relatively small numbers of dentists working in Nigerian teaching hospitals, 133 dentists appear good enough for a pilot survey, especially with an acceptable gender balance and a good representation of different levels of experience. Interestingly also, 88.7% of the respondents were experienced in the treatment of AgP, indicating that the levels of knowledge demonstrated in this study could be safely interpreted as current knowledge among practitioners actively involved in the management of AgP.

Our fear at the beginning of this survey was whether many dentists were not aware or had forgotten the basic knowledge about aggressive periodontitis, as taught in our dental schools. This was predicated on the fact that some of the late-presenting cases of AgP had a positive history of previous dental visits. Evidence from the present study, however, does not support this position as 70% of the respondents identified the teeth involved in LAP and GAP accurately, while over 60% had knowledge of the oral hygiene status in LAP and GAP.

The worrying aspect of the results, however, is the recurring decimal of an inverse relationship between knowledge and experience. It may have been possible to explain this phenomenon away as an inevitable consequence of specialization, but the fact that 88.7% of the respondents admitted treating AgP negates this assumption. This phenomenon is even more worrying because it corroborates a previous study, which recorded declining knowledge of the levels of cardiopulmonary resuscitation, with increasing experience among general dental practitioners.[12]

Admittedly, the study by Eskandari and colleagues is not related to dental knowledge, but it reflects the paradoxical situation where the more trusted members of the profession are less likely to possess adequate knowledge. Although knowledge does not necessarily translate into improved behavior and practice, it is indispensable in distinguishing between different forms and early diagnosis of AgP,[13] which in turn determines the treatment prognosis.[14]

Another serious finding of this study was that half of the respondents had fair to poor general knowledge of aggressive periodontitis. This was quite disturbing and at variance with the findings of an Australian study where 61.9% of the dentists felt confident about treating aggressive periodontitis.[15]

The greater knowledge of AgP demonstrated by males in this study runs contrary to the generally accepted belief that women are more oral health conscious than men.[16] The fact that 12 of the 14 respondents who demonstrated excellent general knowledge of AgP were male, further support the male superiority of knowledge of AgP. However, the differences were not statistically significant in the sample of dentists, to call for further studies in a larger sample to study this effect.

The near complete ignorance of laser therapy options in the management of AgP is not surprising as it is a relatively new phenomenon. Some respondents took a wild guess mentioning Nd-Yag and Co2 lasers as options in the management of AgP. Unfortunately, the Nd-Yag laser has been tried with disappointing results,[17] while the Co2 lasers has failed to reduce bacterial counts, with the risk of damage to the pocket epithelium.[1819] However, the current evidence supports a beneficial and promising role of diode lasers in the management of AgP.[20]

CONCLUSION

Half of the dentists surveyed in this study demonstrated fair to poor knowledge of aggressive periodontitis. Gender- and experience-related differences were found, but were not statistically significant. There is a clear need for improving the knowledge of dentists about aggressive periodontitis, as evidence[21] suggests a direct relationship between the number of days spent on continuing dental education and knowledge of periodontal diseases.