INTRODUCTION: Keratocystic odontogenic tumours (KCOTs) are benign lesions of the jaw that are characterised by expansive growth and high rates of recurrence. Herein, we present a novel minimally invasive method for the surgical treatment of KCOTs. CASE PRESENTATION: We present a 49-year-old woman with a rare, large KCOT of the mandible extending from tooth 37 to tooth 47. A single enucleation procedure was selected as the surgical technique combined with a titanium plate. Teeth interfering with the cystic lumen were preserved. The bone surrounding the cyst was partially removed and rinsed with Carnoy’s solution. Recurrence was observed 1 year later between teeth 43 and 45, and was treated by single enucleation with Carnoy’s solution. After the second operation, the teeth interfering with the KCOT still elicited a positive response to dental pulp testing. No further signs of recurrence were observed after a total observation period of 7 years. DISCUSSION: Various surgical interventions have been described for KCOTs. However, a general guideline for a specific surgical intervention has not yet been established owing to the heterogeneity of these tumours. CONCLUSION: Immediate enucleation in combination with a titanium plate offers an effective surgical approach for the treatment of large KCOTs of the mandible without the need for radical tooth removal or resection of the afflicted side. Highlights:

Background: Maxillary sinus floor augmentation (MSFA) is commonly used to increase posterior maxillary bone volume prior to implant placement. Although generally successful, late complications can impact long-term outcomes. The purpose of the study was to estimate the incidence and timing of atypical late complications following (MSFA) using bovine xenohybrid bone grafts. The study also aimed to evaluate whether preoperative bone volume is associated with the risk of complications. Methods: This retrospective cohort study was conducted at the Center of Oral and Maxillofacial Surgery, Danube Private University, Krems-Stein, Austria, and included patients who underwent MSFA with bovine xenohybrid bone grafts and either simultaneous or staged implant placement between January 2020 and December 2023. Preoperative bone volume of the posterior maxilla measured via cone beam computed tomography (CBCT) in the planned implant insertion position. The primary endpoint was the time (days) from MSFA to the occurrence of a graft-related complication (defined as atypical if occurring more than 6 months after MSFA and not related to peri-implantitis) The covariates included subjects’ age, sex, the quantity of graft used for MSFA, timing of dental implant insertion (simultaneous vs. staged) and implant dimensions. Kaplan–Meier analysis and Cox proportional hazards regression were used to evaluate time-to-event data. Only one graft site per patient was analyzed. Results: Atypical complications occurred in 9 out of 47 patients (19.1%), with an average time to onset of 645 days. In a multivariable analysis, a lower preoperative bone volume was found to be an independent predictor of an increased risk of complications (hazard ratio [HR]: 0.972; 95% confidence interval [CI]: 0.925–1.021; p = 0.252). However, the quantity of graft used for MSFA was not found to be a predictor (p = 0.46). Conclusions: Within the limitations of a retrospective study, reduced native bone volume appears to increase the risk of atypical late complications following MSFA with bovine xenohybrid grafts. This makes closer clinical and radiologic follow-up of patients over a longer period very necessary.

Introduction and importance: Extraction of mandibular third molars can lead to complications such as chronic sclerosing osteomyelitis (CSO), an inflammatory bone marrow disease that tends to progress. CSO involves the cortical plates and often the periosteal tissues and is caused by a variety of microorganisms, including Corynebacterium spp. The treatment of chronic osteomyelitis (CO) and CSO remains challenging, as there is no universal treatment protocol. This case report investigated whether jaw bone that has healed from chronic sclerosing osteomyelitis can be considered healthy bone when planning dental implants. Case presentation: A 21-year-old Caucasian woman developed CO and CSO after third molar surgery. Clinical discussion: A combination of alveolar ridge bone resection, extraction of teeth 47–32, and long-term specific antibiotic therapy against Corynebacterium spp. was administered. An attempt at preprosthetic alveolar ridge reconstruction with an anterior superior iliac crest bone graft resulted in graft failure and the patient refused further harvesting procedures. Implantation in the intraforaminal zone also resulted in the loss of two implants after loading. Finally, inferior alveolar nerve transposition resulted in the successful reimplantation of two implants, which were fully functional almost 11 years later. Conclusion: This case report presents the treatment history of this patient. With a longitudinal observation period of greater than 20 years, the results of this case demonstrate the successful treatment of bone with CO, CSO, and Corynebacterium spp. infection. Following the removal of infected bone, radical debridement, and long-term antibiotic therapy, bone health was restored.

Sinus floor augmentation is an effective method to regain bone height for the successful insertion of dental implants into the posterior maxilla. The aim of the study was to evaluate the behaviour of augmentation material following simultaneous or staged dental implant insertion, as visible on digital panoramic radiographs using the GNU Image Manipulation Program (GIMP). We evaluated one-stage (group 1) or two-stage (group 2) maxillary sinus floor augmentation procedures in 19 patients, using a high temperature-treated bovine porous hydroxyapatite material. Digital panoramic radiographic measurements were captured pre-operatively in both groups, pre-implant insertion in group 2, and immediately postoperatively and 6 months postoperatively in both groups. Forty parallel-walled bone-level implants were placed in a one-stage (n=18) or two-stage (n=22) protocol, with a mean residual bone height of 4.9±1.8 mm and survival rate of 100%. Mean bone height increased by 8.6±1.6 mm immediately post-implantation and by 7.9±1.7 mm after 6 months. Mean distal and mesial bone losses after abutment connection were 0.42±0.24 mm and 0.34±0.27 mm, respectively. No significant intergroup or intragroup differences between simultaneous and staged dental implant procedures were found. Our results show that the histogram tool in GIMP is useful for documentation of the area of the augmentation material used in maxillary sinus floor augmentation.