Periodontal disease epidemiology : assessment of untreated periodontitis and accuracy of partial mouth recording protocols

The current thesis includes three projects that covered several aspects of periodontitis epidemiology. The first project focused on studying the prevalence, extent, and associations with untreated periodontitis. A purposive sample of 431 subjects never treated for periodontal conditions was clinically examined at screening dental school clinics. Background data were collected using questionnaires. The prevalence, extent, and associations with untreated periodontitis were evaluated. Our findings showed that the prevalence and extent of untreated periodontitis were high in untreated subjects. Significant exposures associated with untreated periodontitis included age ≥35 years, male sex, lower education, lower income, uncontrolled diabetes mellitus, current cigarette smoking, and lower perceived stress. The second thesis project compared the performance of partial-mouth recording protocols (PRP) with the full-mouth recording protocol (FRP) to estimate the prevalence, extent, and associations of untreated periodontitis. Three PRPs were selected: full-mouth at the mesiobuccal and distolingual sites [(FM)MB-DL], half-mouth at mesiobuccal and distolingual [(HM)MB-DL] and random-half-mouth (RHM) protocol. The accuracy of PRPs was compared with that of FRP by calculating the sensitivity, negative predictive value, and absolute bias. Our findings showed that PRPs had the highest overall accuracy in estimating the untreated periodontitis prevalence, extent, and associations were the (FM)MB-DL and RHM. The third project focused on studying the accuracy of using PRPs in estimating the prevalence, extent, severity, and associations of periodontitis for population-based studies using a systematic review and meta-analyses. A systematic literature search was conducted to retrieve the studies that examined the accuracy of PRP toward estimating the periodontitis prevalence, its extent, severity, and its associations. Data selection, extraction, synthesis, and meta-analyses were performed for 14 studies that matched the eligibility criteria. Our findings include the following: the PRPs that had the highest overall accuracy in studying the periodontitis prevalence, its extent and severity were the (FM)MB-B-DL, (FM)MB-DL, full-mouth at Mesiobuccal-Midbuccal-Distobuccal [(FM)MB-B-DB] sites, (FM)MB-DB, a total of 84 sites using random site selection method, and RHM. Based on a limited number of studies, estimating the associations with periodontitis using PRPs resulted in marginal bias.Dentistry, Faculty ofGraduat