How effective is a thick plate on stabilisation in 10 mm mandibular advancement?

We compared the stability and stress analysis of four different fixation methods after sagittal split ramus osteotomy (SSRO) in mandibular models. In the first model (1P1B) we adapted a four-hole, 2.0 mm standard miniplate on the osteotomy line with one bicortical screw at the top. In the second (2P) we placed two four-hole 2.0 mm standard miniplates above and below the osteotomy line. In the third (3B), we applied three inverted L-shaped bicortical screws, and in the last (1RP1B) we used a four-hole miniplate with increased thickness on the osteotomy line with one bicortical screw at the top. A static vertical load of 200 Newtons (N) was then applied to each model from the occlusal of the first molar. The maximum and minimum principal stresses on the bone were observed more in the proximal segment close to the osteotomy line in all groups. Maximum von Mises stresses were 2705.21 Megapascals (MPa), 1633.56 MPa, 1121.4 MPa, and 1734.44 MPa for the 1P1B, 2P, 3B, and 1RP1B groups, respectively. Displacement values were 1.92 mm, 1.15 mm, 0.79 mm, and 1.42 mm for the 1P1B, 2P, 3B, and 1RP1B groups, respectively. The reinforced plate contributed to the stabilisation, but it was not as effective as three bicortical screws and a double plate.

Spontaneous bone regeneration in resected non-continuous mandible due to medication-related osteonecrosis of the jaw.

Few cases of spontaneous bone regeneration after extensive resection of the jaw bone have been reported, but it is more common in young adults or children. In this case, we report spontaneous bone healing in a 73-year-old female patient. On radiological examination, necrotic regions were seen in the right mandible. She was diagnosed with medication-related osteonecrosis of the jaw due to previous bisphosphonate use. After segmental resection, stabilization achieved using a reconstruction plate. The periosteum was preserved during the procedure. Twelve months later, panoramic radiography was taken and bone formation was seen both horizontally and vertically around the plate. If the periosteum is preserved and stabilization is achieved after resection in benign lesions, the bone may regenerate spontaneously regardless of age. Therefore, instead of simultaneous autogenous bone application, such patients may be followed to determine whether spontaneous bone healing will occur. This should improve patient comfort and reduce surgical cost.

Management of Large Oroantral Fistulas Caused by Medication-Related Osteonecrosis with the Combined Sequestrectomy, Buccal Fat Pad Flap and Platelet-Rich Fibrin.

PURPOSE: The aim of this retrospective study was to describe the efficacy of management of bisphosphonate-related maxillary osteonecrosis, which had resulted in an oroantral fistula formation, by performing sequestrectomy, platelet-rich fibrin (PRF) and buccal fat pad (BFP) flap. PATIENT AND METHODS: A total of 7 patients diagnosed with stage III maxillary medication-related osteonecrosis according to guidelines of the American Association of Oral and Maxillofacial Surgeons. All patients complained of persistent pain, swelling and purulent drainage with sinusitis. In order to keep the infection under control, the patients first received an antibiotic combination for 2 weeks. Then, sequestrectomy and bone debridement were performed under general anesthesia. After that, an antrectomy was performed via endoscopic sinus surgery in some cases. And the fistula was closed with BFP after or before the PRF application to the region depending on the size of the fistula. RESULTS: The fistula was successfully closed. After a mean follow-up of 16 months, no symptoms were seen in the patients. CONCLUSIONS: The patients were successfully managed with a combined treatment consisted of sequestrectomy, PRF and BFP. We suggest that large defects arose from medication-related osteonecrosis of the jaw can be managed with such a combined approach in order to lessen the recurrence risk.