Incidental findings in cone beam computed tomography (CBCT) scans for implant treatment planning: a retrospective study of 404 CBCT scans.

OBJECTIVES: To investigate the prevalence of incidental findings and need for further dental treatment and analyse the influence of size of field-of-view (FOV) and age in cone beam computed tomography (CBCT) for pre-implant planning. METHODS: 404 CBCT scans were examined retrospectively for incidental findings and need for further dental treatment. Incidental finding-frequencies and need for further treatment were assessed for different age (< 40 years, 40-60 years, > 60 years) and FOV groups (small, medium, large). Intraexaminer and interexaminer agreements were evaluated. RESULTS: In 82% of the scans at least one incidental finding was found, with a total of 766 overall. More incidental findings were found in scans with large FOV (98% vs. 72%, OR = 22.39 large vs. small FOV, p < 0.0001) and in scans of patients > 60 years (OR = 5.37 patient's age > 60 years vs. < 40 years, p = 0.0003). Further dental treatment due to incidental findings was needed in 31%. Scans with large FOV were more likely to entail further treatment (OR = 3.55 large vs. small FOV, p < 0.0001). Partial edentulism and large FOV were identified as risk factors for further treatment (p = 0.0003 and p < 0.0001). Further referral of the patient based on incidental findings was judged as indicated in 5%. Intra- and inter-examiner agreements were excellent (kappa = 0.944/0.805). CONCLUSIONS: A considerable number of incidental findings with need for further dental treatment was found in partially edentulous patients and in patients > 60 years. In pre-implant planning of elderly patients, the selection of large FOV CBCT scans, including dentoalveolar regions not X-rayed recently, help to detect therapeutically relevant incidental findings.

[Surgical removal of an atypically large extensive radicular cyst in the mandible: a case report.] / Atypisch grosse radikuläre Zyste. Operative Entfernung einer atypisch grossen ausgedehnten radikulären Zyste im Unterkiefer, ein Fallbericht.

The radicular cyst is the most common odontogenic cyst and is caused by inflammation. It can become atypically large, although the size of the radiographic osteolysis says nothing about the entity of the lesion. This case shows an unusually large multilocular radicular cyst expanding buccally from tooth 46 in a patient with severe autism who can only be treated under general anesthesia. The clinical and radiological picture as well as the intraoperative situation was more indicative of an aggressive cyst or benign tumor. The lesion was surgically completely removed and the teeth 46, 47 and 48 were extracted because of poor compliance and prognosis. Histopathology revealed a radicular cyst. There were no postoperative complications. After eight months, the lesions had almost completely reossified.

Influence of bolus size and chewing side on temporomandibular joint intra-articular space during mastication.

Previous studies suggested that, during mastication, magnitude and location of mechanical load in the temporomandibular joint (TMJ) might depend on chewing side and bolus size. Aim of this study was to dynamically measure the TMJ space while chewing on standardized boluses to assess the relationship among minimum intra-articular distances (MID), their location on the condylar surface, bolus size, and chewing side. Mandibular movements of 12 participants (6f, 24±1y.o.; 6 m, 28±6y.o.) were tracked optoelectronically while chewing unilaterally on rubber boluses of 15 × 15 × 5, 15 × 15 × 10, and 15 × 15 × 15 mm3 size. MID and their location along the main condylar axis were determined with dynamic stereometry. MID were normalized on the intra-articular distance in centric occlusion. Repeated measures ANOVA (α = 0.05) showed that MID were smaller on the balancing (0.74±0.19) than on the working condyle (0.89±0.16) independently of bolus size (p < 0.0001). MIDs did not differ between 5 and 10 mm bolus thicknesses (0.80±0.17) but increased for 15 mm (0.85±0.22, p = 0.024) and were located mostly laterally, close to the condylar center. This study confirmed higher reduction of TMJ space on the balancing than on the working condyle during mastication. Intra-articular distances increased significantly for the greatest bolus thickness. Loaded areas were located laterally, for both working and balancing joint.