Are there difficulty variables in maxillary third molar surgery? A prospective observational cohort study.

BACKGROUND: The main aim of the present study was to assess which factors were related to surgical difficulty in maxillary third molar extraction. Intra- and postoperative complications were also evaluated. METHODS: A prospective observational cohort study was performed on out-patients who underwent impacted maxillary third molar extraction. Principal component analysis and multiple linear regression were used to assess the correlation among variables as well as the influence of different preoperative variables on surgical difficulty, suture duration and risk of intraoperative complications. RESULTS: Eighty-six teeth were extracted. There was a positive correlation between pre- and postoperative evaluations and surgery duration. Available space for surgical access in the upper fornix, second molar contact, crown palatal position, depth of the elevation point and surgeon's seniority had a significant effect on the overall difficulty index. Risk of intraoperative complications increased considerably as the percentage of reduction of maximum mouth opening increased (2.03±0.98) as well as in cases in which ostectomy and tooth sectioning were performed (7.02±2.68). The surgeon's seniority was associated with a decreased risk of intraoperative complications (-1.52±0.72). Surgeons were able to predict the difficulty of surgery only to a limited extent. CONCLUSIONS: The percentage of maximum mouth opening reduction with an object in the fornix, crown palatal position, and contact with the second molar were found to be related to surgical difficulty.

A Prospective Observational Study on the Variables Affecting the Risk of Inferior Alveolar Nerve Damage During Lower Third Molar Surgery With Nerve/Root Proximity.

PURPOSE: The present study aimed to evaluate which factors were statistically associated with a greater probability of inferior alveolar nerve (IAN) damage during lower third molar surgery. METHODS: A prospective observational study was performed at the Oral Surgery Unit of the Umberto I Hospital on 92 patients who underwent surgical extraction of a lower third molar that was radiographically overlapped with the mandibular canal. All surgeries were performed by the same expert surgeon. A principal component analysis and the exact 2-tailed Fisher exact test were used. RESULTS: Temporary IAN damage occurred in 10 cases (10.9%). Symptoms lasted from 18 to 180 days (73 ± 49.15). IAN damage was more frequent in difficult and long-lasting surgeries, in the presence of many risk factors and in patients with a reduced maximum mouth opening. CONCLUSION: Such factors should be accurately evaluated before surgery to assess and discuss the overall surgical risk of IAN damage with the patient especially when they are over the maximum limit of their significant variability range found in the present study, that is, >12 for difficulty index, >2 for number of orthopantomography risk markers and <3.7 cm for maximum mouth opening.