FDG-PET/CT for oral focus assessment in head and neck cancer patients.

OBJECTIVES: To compare oral and maxillo-mandibular inflammatory foci on standard oral radiographs (OPT, periapical radiograph) with available fluorine-18-labelled fluoro-2-deoxy-D-glucose-positron emission tomography/computed tomography (FDG-PET/CT) data and to discuss whether additional metabolic information derived from FDG-PET/CT can support oral care specialists when performing oral focus examinations. MATERIALS AND METHODS: Data from 23 patients with head and neck cancer who underwent FDG-PET/CT and panoramic and periapical radiography in close succession before first-line radiotherapy and/or chemotherapy were included in this exploratory retrospective study. Periapical lesions and marginal periodontal inflammation on FDG-PET/CT scans and standard oral radiographs were analysed and compared with regard to metabolic activity on FDG-PET/CT in comparison to recorded clinical symptoms and radiological scores. Additionally, inflammatory maxillo-mandibular pathologies were analysed using FDG-PET/CT. RESULTS: The maximum standardised uptake value (SUVmax) in FDG-avid marginal periodontal sites could not be conclusively associated with the radiologically recorded severity of marginal bone loss, but a potential positive correlation was identified. No association was found either between the metabolic activity of periapical lesions and their extent, as recorded on standard oral radiographs, or regarding clinical symptoms (percussion test). Most maxillo-mandibular pathologies did not show increased FDG uptake. CONCLUSIONS: FDG-PET/CT provided additional metabolic information that can help clinicians identify lesions with increased inflammatory activity. The incorporation of available oral FDG-PET/CT findings into the primary oral focus assessment may allow for more accurate oral focus treatment. CLINICAL RELEVANCE: FDG-PET/CT provides valuable metabolic information for oral care specialists. The detection of inflammatory oral processes using FDG-PET/CT facilitates treatment.

Evaluation of Preventive Treatment Protocols for Patients under Antiresorptive Therapy Undergoing Tooth Extraction at a Swiss University Clinic.

Antiresorptive agent-related osteonecrosis of the jaw (ARONJ) is a dreaded complication in patients with compromised bone metabolism. The purpose of the present study was to examine the occurrence of ARONJ and its related factors among patients with a history of antiresorptive therapy undergoing tooth extraction using preventive protocols at a Swiss university clinic. Data were retrospectively pooled from health records of patients having received a surgical tooth extraction between January 2015 and April 2020 in the Clinic of Cranio-Maxillofacial and Oral surgery, University of Zurich. A total of 970 patients received an extraction with flap elevation or wound closure during this period. A total of 104 patients could be included in the study. Furthermore, variables including age, gender, smoking, risk profile, choice, indication and duration of antiresorptive therapy, number of extractions, extraction site, surgical technique, choice and duration of antibiotics as well as the presence of postoperative inflammatory complications were assessed. Overall, 4 patients developed ARONJ (incidence of 3.8%) after tooth extraction at the same location, without previous signs of osteonecrosis. Preventive methods included predominantly primary wound closure using a full thickness mucoperiosteal flap and prolonged perioperative antibiotic prophylaxis. In accordance with current literature, the applied protocol showed a reliable outcome in preventing ARONJ when a tooth extraction is required.