Abstract
ObjectiveTo analyze the prevalence of distal caries in mandibular second molars (M2Ms) and its correlation with the three-dimensional position of mandibular third molars (M3Ms) by cone beam computed tomography (CBCT) images.Materials and methodsCBCT scans involving 421 M3Ms were assessed. The presence of distal caries of M2Ms, patient age and gender, impaction depths and mesial angulation of M3Ms, the cementoenamel junction (CEJ) distances and contact point localization, and the horizontal positions of M3Ms were assessed. Risk factors were identified by multivariate logistic regression analysis.ResultsThe overall prevalence of distal caries in M2Ms was 31.6%. Mesial angulation (16°–75°) of M3Ms, contact point localization at or below the CEJ of M2Ms, and a buccal or lingual position of M3Ms relative to the molar line were identified as risk factors for the prevalence of distal caries in M2Ms (p < 0.05). Distal caries was more severe when the mesial angulation of M3Ms was 16°–75° (p < 0.05).ConclusionsBuccal or lingual position of M3Ms may represent a new risk factor for the distal caries in M2Ms. Mesial angulation (16°–75°) of M3Ms is a predictive parameter for both the presence and severity of distal caries in M2Ms.Clinical relevanceAs the presence of distal caries in M2Ms is significantly associated with the three-dimensional position of M3Ms, watchful monitoring or prophylactic removal of M3Ms should be deliberated when M3Ms are mesially angulated (16°–75°), buccally or lingually positioned, and with the contact point localization at or below the CEJ of M2Ms.
Highlights
Third molars often fail to completely erupt into function due to either lack of space, development in an abnormal position, or aberrant eruption path and may bear pathological changes including periodontitis, pericoronitis [1], cystic lesions [2], and development of cysts or tumors [3]
Many studies correlating the presence of distal caries in M2Ms and the eruption status of M3Ms have been performed using periapical or panoramic radiographs
Pearson’s chi-square independence tests indicated that mesial angulation and the buccal or lingual position of M3M, cementoenamel junction (CEJ) distance, and contact point localization were associated with the presence of distal caries in M2Ms (p < 0.05; Table 1)
Summary
Third molars often fail to completely erupt into function due to either lack of space, development in an abnormal position, or aberrant eruption path and may bear pathological changes including periodontitis, pericoronitis [1], cystic lesions [2], and development of cysts or tumors [3]. They were associated with caries in the distal surfaces of adjacent mandibular second. Using periapical or panoramic radiographs, the mesial angulation, the vertical position of M3M, and the distance between M2M and M3M have been found to be the risk factors for distal caries in M2Ms [2, 4,5,6, 9,10,11].
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
