Timing of development of osteoradionecrosis post head and neck radiotherapy: does a safe time interval exist for dental extraction?

INTRODUCTION: Risk factors for developing osteoradionecrosis (ORN) are well known, but less is known about factors influencing the interval between radiotherapy and the onset of ORN. Also, it is unknown whether there is any specific period post-radiotherapy with a reduced probability of ORN when irradiated teeth require extraction. PURPOSE: The primary aim of this study was to identify factors influencing the interval in developing ORN in the following subgroups of patients: (1) patients who spontaneously developed ORN, (2) surgical-intervention-related ORN with a particular focus on patients after mandibulectomy. The secondary aim was to attempt to identify a possible time for safer dental intervention after primary treatment. MATERIALS AND METHODS: The authors retrospectively analysed 1608 head and neck cancer (HNC) patients treated in a single centre. Time intervals were measured from the end of radiotherapy to the development of ORN and further analysed in the subgroups listed above. RESULTS: In all, 141 patients (8.8%) developed intra-oral ORN. Median time from radiotherapy to ORN development in the whole cohort was 9 months. Median interval for spontaneous ORN was 8 months, 6.5 months for intervention-related ORN, and 15 months for patients post-mandibulectomy. In patients who required dental extraction preradiotherapy, median interval of ORN onset was 5 months. CONCLUSION: In our study, a slightly higher proportion of patients with intervention developed ORN earlier in comparison with spontaneous ORN. The period from 12-18 months after radiotherapy was identified as having the highest probability of developing ORN in patients after mandibulectomy. A time for safer dental intervention after primary treatment was not identified.

The Stability of Anterior Open Bite Closure After Bimaxillary Osteotomy.

Introduction: The aim of this study was to evaluate the long-term success rate of combined surgical-orthodontic therapy of skeletal anterior open bite. Materials and Methods: A total of 11 patients with an anterior open bite treated with a combined surgical-orthodontic therapy were retrospectively analysed via lateral cephalometric radiographs and models before treatment, 7-10 days after surgery (T1), one year post-operatively (T2) and two years post-operatively (T3). Results: Ten patients continued to experience a positive overbite at T2. This decreased to 8 at T3. Three patients experienced relapse and had a negative overbite at T3. The average pre-treatment overbite was greater in the positive overbite group compared to the relapse group. Spearman's correlation analysis revealed a correlation between preoperative maxilla-mandibular plane angle (MMPA) with the overall change in overbite. Friedman's test followed by Bonferroni post-hoc analysis was carried out to identify any statistical significance. Conclusion: In conclusion, combined surgical-orthodontic treatment achieves good results for anterior open bite. Patients with a high pre-operative MMPA have a higher risk of relapse. Lower anterior facial height ratio to total anterior facial height (LAFH/TAFH) and the amount of impaction do not significantly contribute to the risk of relapse. Long-term stability of overbite for anterior open bite patients should be around 75%.

Functional outcomes following mandibulectomy and fibular free-flap reconstruction.

There remains a paucity of evidence with regards to functional outcomes following the reconstruction of segmental defects in the mandible. It is, however, well recognised that oral rehabilitation following head and neck surgery is a driver of improved quality of life outcomes. We present a prospective service review of functional outcomes of a consecutive cohort of patients following segmental mandibulectomy and virtual surgical planning (VSP) composite fibular free-flap reconstruction. Twenty-five patients, who were identified as having a complete dataset with a minimum of 12 months' follow up, ultimately met the inclusion criteria. Validated functional outcome measures were used primarily to assess speech, diet, and swallowing outcomes. The results demonstrate a decline in both speech and swallowing outcomes at three months postoperatively, with a decline of 37% in the Speech Handicap Index from the preoperative baseline, and a decline of 35% in the MD Anderson Dysphagia Inventory score over the same period. The MD Anderson Dysphagia Inventory score improved at 12 months, whereas the Speech Handicap Index did not. Fundamentally a collaborative approach is required between members of the multidisciplinary team (MDT) to enable optimal patient outcomes.

Dosimetry-guided virtual surgical planning in the reconstruction of mandibular osteoradionecrosis.

Patients with osteoradionecrosis (ORN) of the mandible pose additional challenges to the attending clinician when it comes to major reconstructive head and neck surgery. We present a novel technique to assist in the virtual surgical planning of mandibular ORN, which involves deforming previously delivered radiation dosimetry data on to the virtual mandible to aid in the assessment of surgical resection margins. This is a retrospective case series of patients whose treatment involved a traditional virtual surgical planning approach or dosimetry-guided virtual surgical planning. All the patients whose treatment involved dosimetry-guided virtual surgical planning had evidence of bony consolidation between the native mandible and fibular free flap. In comparison, only three of the nine patients in the traditional virtual surgical planning group demonstrated bony healing on subsequent imaging. In this known cohort of difficult-to-manage patients, any technique that helps to improve outcomes is a welcome addition to the armamentarium of the surgeon.