Third-Molar Status and Risk of Loss of Adjacent Second Molars

Abstract

The prophylactic removal of asymptomatic third molars is a common but controversial procedure often rationalized as necessary to prevent future disease on adjacent teeth. Our objective in this retrospective cohort study of adult men was to examine whether second-molar loss differed by baseline status of the adjacent third molar, taking into account the individual’s overall state of oral hygiene, caries, and periodontitis. We analyzed data from participants of the VA Dental Longitudinal Study who had at least 1 second molar present at baseline and 2 or more triennial dental examinations between 1969 and 2007. We classified second molars by third-molar status in the same quadrant: unerupted, erupted, or absent. Tooth loss and alveolar bone loss were confirmed radiographically. Caries and restorations, calculus, and probing depth were assessed on each tooth. We estimated the hazards of second-molar loss with proportional hazards regression models for correlated data, controlling for age, smoking, education, absence of the first molar, and whole-mouth indices of calculus, caries, and periodontitis. The analysis included 966 men and 3024 second molar/first molar pairs. Follow-up was 22 ± 11 y (median 24, range 3–38 y). At baseline, 163 third molars were unerupted, 990 were erupted, and 1871 were absent. The prevalence of periodontitis on the second molars did not differ by third-molar status. The prevalence of distal caries was highest on the second molars adjacent to the erupted third molars and lowest on the second molars adjacent to the unerupted third molars. Relative to the absent third molars, adjusted hazards of loss of second molars were not significantly increased for those adjacent to erupted (hazard ratio [HR] = 0.96, 95% confidence interval [CI] = 0.79–1.16) or unerupted (HR = 1.25, 95% CI = 0.91–1.73) third molars. We found similar results when using alveolar bone loss as the periodontitis indicator. Our findings suggest that retained third molars are not associated with an increased risk of second-molar loss in adult men.

Classification of caries in third molars on panoramic radiographs using deep learning

“…The removal of third molars is one of the most commonly performed surgical procedures in oral surgery. Recent guidelines recommend the removal of pathologically erupting third molars in order to prevent future complications 1 , 2 . The second molar is frequently disrupting the eruption path of the third molar, evoking it to only erupt partially or not at all, which can adversely affect periodontal health of the second molar.…”

Diş Çekim Endikasyonu ve Sosyodemografik Özelliklerine Göre Üçüncü Molar Diş Prevalansı

“…Aynı şekilde bu dişlerin etrafında ameloblastik ya da neoplastik kitle görülme ihtimalinin %1'den az olduğu belirtilmiştir. 20,21 Bu oranların, asemptomatik üçüncü molar dişlerde profilaktik çekim kararı alınabilmesi için yeterli olmadığını düşünmekteyiz. Çalışmamızda kist-tümör oluşumu sebebiyle çekim endikasyonu koyulan dişler tüm çekilen dişlerin %7.51'ini oluştururken, profilaktik olarak çekilen dişlerin oranı %1.98'dir.…”

How the Loss of Second Molars Corresponds with the Presence of Adjacent Third Molars in Chinese Adults: A Retrospective Study

“…Compared with M2s without neighboring M3s, retained impacted M3s have been confirmed to increase the risk of M2 pathology by 2.16- to 4.88-fold [ 11 ]. Interestingly, Kaye and colleagues recently reported that retained M3s were not associated with an increased risk of M2 loss among adult men (average age: 48 years) [ 39 ]. Their study excluded participants whose M2s were already extracted, and this leads us to the opposite conclusion.…”