Is it necessary to remove bone-impacted teeth? A retrospective study.

Background: In clinical practice, it is risky to extract bone-impacted teeth and they're prone to a variety of complications, such as pathological fracture, adjacent tooth fracture, maxillary sinus perforation, and so on, making it difficult for clinicians to decide whether to extract them.

Purpose: In order to illustrate our opinions on the possibility of extracting full third molars (M3), 360 examples of complete third molars were analyzed in this study.

Materials And Method: We investigated 2189 patients, and 261 of them provided CBCT images of 360 teeth. assessing the degree of second molar(M2) root absorption in connection to age, impacted relationship, contact part, calculating the odds ratio (OR) and 95% confidence interval using the Logistic regression analysis equation.

Result: Bone-impacted M3 occurred in 11.92% (261/2189) of patients with "impacted teeth" diagnoses. There was a significant difference between the occurrence of M2ERR and the contact parts (P value<0.001), and only the type of vertical impaction differed significantly from Level 3 (P < 0.05).

Conclusions: 1) M3 should be removed if root resorption has not occurred in M2. 2) Root resorption is more likely to occur when M3 crown and M2 apical contact. 3) Enough experience, precise preoperative assessment can reduce the dangers to a minimum.