Prevalence of distal caries in second molar associated with impacted mandibular third molar and the position and level of impaction: a systematic review and meta-analysis.

OBJECTIVES

The primary objective of this systematic review was to analyze the overall prevalence of distal caries in mandibular second molars (MSMs) associated with the presence of impacted mandibular third molars (IMTMs). Secondary objectives were to determine how IMTM position and level of impaction influence the occurrence of distal caries.

MATERIALS AND

METHODS

PRISMA guidelines were followed. An automated search was conducted as well as a manual search for relevant clinical articles. The review included studies reporting IMTM and adjacent MSM presenting distal caries published in the last ten years. The quality of evidence was evaluated using the Newcastle-Ottawa Quality Assessment Scale.

RESULTS

Thirteen studies met the inclusion criteria and underwent analysis; they included a total of 13,788 patients. The overall prevalence of caries in MSMs adjacent to IMTMs was 29.89% (CI 95%: 21.05 - 38.74%; p < 0.001). Following Winter's classification, the mesioangular position was the most frequently associated with caries with 43.37% (CI 95%: 33.03 - 53.70%; p < 0.001). Following Pell & Gregory classification, position A was the most frequently associated with caries with 33.97% (CI 95%: 24.06 - 43.89%; p < 0.001).

CONCLUSIONS

IMTMs in mesioangulated positions, especially if accompanied by level A impaction, present the highest risk of MSM distal caries.

CLINICAL RELEVANCE: Knowing which positions and level of IMTMs are most frequently associated with distal caries in MSMs is crucial to implementing preventive measures.

REVIEW REGISTRATION: This systematic review was registered in the International Prospective Register of Systematic Reviews (PROSPERO). Reg. number: CRD42023393143.