Influence of Non‐Impacted Third Molars on Pathologies of Adjacent Second Molars: A Retrospective Study. Issue 5 (1st May 2017)

• Record Type: Journal Article
• Authors: Li, Zhi‐Bang; Qu, Hong‐Lei; Zhou, Li‐Na; Tian, Bei‐Min; Chen, Fa‐Ming
• Is Part Of: Journal of periodontology. Volume 88:Issue 5(2017)
• Page Start: 450
• Page End: 456
• Publication Date: 2017-05-01
• Subjects: Dental caries -- molar -- molar, third -- periodontitis -- radiography, panoramic -- root resorption; Periodontics -- Periodicals; 617.632
• DOI: 10.1902/jop.2016.160453
• Languages: English
• ISSNs: 0022-3492

Abstract

Abstract : Background: Although removal of impacted third molars (I‐M3s) is common in dental clinics, the decision to retain or remove asymptomatic non‐impacted third molars (N‐M3s) presents a significant challenge. This study investigates influence of N‐M3s on pathologies of adjacent second molars (A‐M2s). Methods: Clinical status of M3s was evaluated, and presence of distal caries, external root resorption (ERR), and alveolar bone loss (ABL) of A‐M2s was assessed by orthopantomograms (OPGs). Prevalence of A‐M2 pathologies was evaluated and association between N‐M3s and pathologies of A‐M2s was analyzed by multivariate logistic regression. Significance level was set at 0.05. Results: OPGs from 1, 958 patients were included in the present study. Among these patients, 45.1% presented with at least one N‐M3, and 44.2% of retained M3s were non‐impacted. Where N‐M3s were present, prevalence of distal caries, ERR, and ABL of A‐M2s was 10.0%, 0.8%, and 40.4%, respectively. Although N‐M3s did not increase the odds of caries or ERR of A‐M2s, presence of N‐M3s was associated with 1.77 times higher likelihood of ABL from A‐M2s when data were adjusted for age and sex. Conclusions: Presence of N‐M3s, even if they are asymptomatic, represents an important risk factor for periodontal health of A‐M2s. This finding should be considered during clinical decision making regarding retention or extraction of N‐M3s, especially when these teeth are non‐functional or when their removal will not affect overall occlusal function.