Coronectomy of deeply impacted lower third molar : incidence of outcomes and complications after one year follow-up

Objectives: The purpose of present study was to assess the surgical management of impacted third molar with proximity to the inferior alveolar nerve and complications associated with coronectomy in a series of patients undergoing third molar surgery. Material and Methods: The position of the mandibular canal in relation to the mandibular third molar region and mandibular foramen in the front part of the mandible (i.e., third molar in close proximity to the inferior alveolar nerve [IAN] or not) was identified on panoramic radiographs of patients scheduled for third molar extraction. Results: Close proximity to the IAN was observed in 64 patients (35 females, 29 males) with an impacted mandibular third molar. Coronectomy was performed in these patients. The most common complication was tooth migration away from the mandibular canal (n = 14), followed by root exposure (n = 5). Re-operation to remove the root was performed in cases with periapical infection and root exposure. Conclusions: The results indicate that coronectomy can be considered a reasonable and safe treatment alternative for patients who demonstrate elevated risk for injury to the inferior alveolar nerve with removal of the third molars. Coronectomy did not increase the incidence of damage to the inferior alveolar nerve and would be safer than complete extraction in situations in which the root of the mandibular third molar overlaps or is in close proximity to the mandibular canal

Osseous reconstruction using an occlusive titanium membrane following marginal mandibulectomy: proof of principle

Guided bone regeneration using barrier membranes is useful in bone augmentation. In contrast to flexible membranes, stiff membranes such as titanium membranes are capable of maintaining sufficient space underneath them. We report a case of bone regeneration under an occlusive titanium membrane following marginal mandibulectomy in a 50-year-old patient with odontogenic keratocyst. Preoperative analysis of the anatomical conditions was evaluated with panoramic radiographs and spiral computer tomography (CT) scan. The digital data from the CT scan were transferred to a personal computer. Using Simplant software, a mirror image of the right mandible was constructed from which a custom-made titanium membrane was made. The cyst with the remaining inferior alveolar nerve was removed and curettage of the lesion was performed under general anesthesia. The definitive titanium plate was inserted and fixated with osteosynthesis screws, and then removed 5 years later. Postoperative CT scanning showed good healing, bone growth under the titanium plate, and no evidence of residual cyst The titanium plate reinforced the mandibular skeleton and restored the shape of the mandible and facial symmetry; it also promoted new bone formation to fill in the mandibular defects

Accuracy of Dental Implant Placement Using CBCT-Derived Mucosa-Supported Stereolithographic Template

Purpose The aim of the present in vivo study was to evaluate whether a difference exists between the maxilla and the mandible regarding the precision of implant placement utilizing a cone beam computed tomography (CBCT)-derived mucosa-supported stereolithographic (SLA) template. Materials and Methods Eighty implants (44 maxilla, 36 mandible) were placed in 18 fully edentulous jaws (10 maxillas, eight mandibles) using a mucosa-supported SLA surgical template. A voxel-based registration technique was applied to match the postoperative and preoperative CBCT scans. Results Vertical deviation (p = .026) at the implant hex and angular deviation (p = .0188) were significantly lower in the maxilla than in the mandible. The global linear deviation and lateral deviation at the implant hex were not significantly different. At the implant apex, the average maximum vertical deviation was within 1 mm (0.1–4.6 mm). The average maximum lateral deviation was 1.8 mm (0.9–5.5 mm) in the maxilla and 2.3 mm (0.5–5.5 mm) in the mandible when a 15-mm-long implant was placed. Conclusions When using CBCT-derived mucosa-supported SLA templates, clinicians should be aware of differences in the angular deviation of the implants in the mandible and maxilla. The average maximum linear deviation should be considered as a safety margin at the implant apex

Accuracy of dental implant placement using CBCT-derived mucosa-supported stereolithographic template

PURPOSE: The aim of the present in vivo study was to evaluate whether a difference exists between the maxilla and the mandible regarding the precision of implant placement utilizing a cone beam computed tomography (CBCT)-derived mucosa-supported stereolithographic (SLA) template. MATERIALS AND METHODS: Eighty implants (44 maxilla, 36 mandible) were placed in 18 fully edentulous jaws (10 maxillas, eight mandibles) using a mucosa-supported SLA surgical template. A voxel-based registration technique was applied to match the postoperative and preoperative CBCT scans. RESULTS: Vertical deviation (p = .026) at the implant hex and angular deviation (p = .0188) were significantly lower in the maxilla than in the mandible. The global linear deviation and lateral deviation at the implant hex were not significantly different. At the implant apex, the average maximum vertical deviation was within 1 mm (0.1-4.6 mm). The average maximum lateral deviation was 1.8 mm (0.9-5.5 mm) in the maxilla and 2.3 mm (0.5-5.5 mm) in the mandible when a 15-mm-long implant was placed. CONCLUSIONS: When using CBCT-derived mucosa-supported SLA templates, clinicians should be aware of differences in the angular deviation of the implants in the mandible and maxilla. The average maximum linear deviation should be considered as a safety margin at the implant apex