Unicystic ameloblastoma (UAM) of the jaw can be effectively reduced in volume through decompression, which promotes bone regeneration and restores jaw symmetry. This study quantitatively evaluated changes in mandible volume and symmetry following decompression of mandibular UAM. This study included 17 patients who underwent surgical decompression followed by second-stage curettage for mandibular UAM. Preoperative and postoperative three-dimensional computed tomography (CT) images were collected. Bone volume and the area of cortical perforation were measured to assess bone growth during decompression. Mandibular volumetric symmetry was analyzed by calculating the volumetric ratio of the two sides of the mandible. Twelve pairs of landmarks were identified on the surface of the lesion regions, and their coordinates were used to calculate the mean asymmetry index (AI) of the mandible. Paired t-tests and the Mann-Whitney U test were used for statistical analysis, with p < 0.05 considered indicative of statistical significance. The mean duration of decompression was 9.41 ± 3.28 months. The mean bone volume increased by 8.07 ± 2.41%, and cortical perforation recovery was 71.97 ± 14.99%. The volumetric symmetry of the mandible improved significantly (p < 0.05), and a statistically significant decrease in AI was observed (p < 0.05). In conclusion, UAM decompression enhances bone growth and symmetry recovery of the mandible. The present evaluation technique is clinically useful for quantitatively assessing mandibular asymmetry.

BACKGROUND: Odontogenic carcinoma with dentinoid (OCD) is a rare and controversial entity, which has not yet been included in the current World Health Organization classification of odontogenic lesions. Owing to the small number of reported cases, the clinicopathological characteristics, biological behavior, prognosis, and appropriate treatment strategies for OCD remain to be defined. Herein, we present an additional case of OCD with a focus on the differential diagnosis and review of the pertinent literature, in order to enable better recognition by oral clinicians and pathologists and further characterization of this entity.
METHODS: This paper reports a case of OCD in the posterior mandible of a 22-year-old female. Radiography showed a well-defined unilocular radiolucency with radiopaque materials. The intraoperative frozen section pathology gave a non-committed diagnosis of odontogenic neoplasm with uncertain malignant potential. Then a partial mandibulectomy with free iliac crest bone graft and titanium implants was performed. Microscopically, the tumor consisted of sheets, islands, and cords of round to polygonal epithelial cells associated with an abundant dentinoid matrix. Immunohistochemically, the tumor cells were diffusely positive for CK19, p63, and β-catenin (cytoplasmic and nuclear). No rearrangement of the EWSR1 gene was detected. The final diagnosis was OCD. There has been no evidence of recurrence or metastasis for 58 months after surgery. We also provide a literature review of OCD cases, including one case previously reported as ghost cell odontogenic carcinoma from our hospital.
CONCLUSIONS: OCD is a locally aggressive low grade malignancy without apparent metastatic potential. Wide surgical excision with clear margins and long-term period follow-up to identify any possible recurrence or metastases are recommended. Histopathological examination is essential to conclude the diagnosis. Special care must be taken to distinguish OCD from ghost cell odontogenic carcinoma and clear cell odontogenic carcinoma, as misdiagnosis might lead to unnecessary overtreatment. Study of additional cases is required to further characterize the clinicopathological features and clarify the nosologic status and biological behavior of this tumor.

Odontome gelten zusammen mit den Amelo- blastomen als die häufigsten odontogenen Tumoren. Sie entstehen während der embryo- nalen Zahnkeimentwicklung durch fehlerhaft differenziertes Keimgewebe und werden daher auch als Hamartome bezeichnet. Somit sind sie also strenggenommen keine klassischen Neoplasien.

BACKGROUND: A central giant cell granuloma (CGCG) is a benign, proliferative, intraosseous, and non-odontogenic lesion occurring primarily in children and young adults. On the histological level, it is characterized by numerous multinucleated giant cells scattered randomly throughout a sea of spindle-shaped mesenchymal stromal cells which are dispersed throughout the fibrovascular connective tissue stroma containing areas of haemorrhage. When it comes to radiographic features, CGCG can have an array of variations, ranging from well-defined expansile lesions to ill-defined and destructive lesions, with or without expansion.
METHODS: This case report reviews an 11-year-old Caucasian patient with a chief complaint of slow-growing swelling involving the right posterior mandibular region. The cone beam computed tomography (CBCT) revealed an ill-defined mixed lesion mimicking both fibro-osseous lesion and hemangioma. However, microscopic examination revealed multinucleated giant cells in a fibrous stroma suggestive of central giant cell granuloma.
CONCLUSIONS: Our intent in reporting this case is to highlight the importance of thorough clinical, radiographical and histopathological examination for accurate diagnosis and therapeutic interventions as well as to emphasize the importance of taking different possibilities into consideration when examining bony swellings in the head and neck region.

Salivary gland neoplasms account for 3% of all head and neck tumours. Pleomorphic adenoma (PA) is the most common salivary gland tumour that mainly occurs in the parotid gland, followed by minor salivary glands of the oral cavity, however, the occurrence of PA inside the jaw bones is exceedingly rare and very few cases have been reported in the literature. Inside jaw bones these lesions tend to imitate large osteolytic lesions encompass a diagnostic challenge. An exhaustive review of the literature revealed only 10 cases of central pleomorphic adenoma. We present a rare case of primary PA that occurred inside the mandible and was provisionally diagnosed as ameloblastoma.

UNASSIGNED: To explore the feasibility and effectiveness of mixed reality technology for localizing perforator vessels in the repair of mandibular defects using free fibular flap.
UNASSIGNED: Between June 2020 and June 2023, 12 patients with mandibular defects were repaired with free fibular flap. There were 8 males and 4 females, with an average age of 61 years (range, 35-78 years). There were 9 cases of ameloblastomas and 3 cases of squamous cell carcinomas involving the mandible. The disease duration ranged from 15 days to 2 years (median, 14.2 months). The length of mandibular defects ranged from 5 to 14 cm (mean, 8.5 cm). The area of soft tissue defects ranged from 5 cm×4 cm to 8 cm×6 cm. Preoperative enhanced CT scans of the maxillofacial region and CT angiography of the lower limbs were performed, and the data was used to create three-dimensional models of the mandible and lower limb perforator vessels. During operation, the mixed reality technology was used to overlay the three-dimensional model of perforator vessels onto the body surface for harvesting the free fibular flap. The length of the fibula harvested ranged from 6 to 15 cm, with a mean of 9.5 cm; the size of the flap ranged from 6 cm×5 cm to 10 cm×8 cm. The donor sites were sutured directly in 7 cases and repaired with free skin grafting in 5 cases.
UNASSIGNED: Thirty perforator vessels were located by mixed reality technology before operation, with an average of 2.5 vessels per case; the distance between the exit point of the perforator vessels located before operation and the actual exit point ranged from 1 to 4 mm, with a mean of 2.8 mm. All fibular flaps survived; 1 case had necrosis at the distal end of flap, which healed after dressing changes. One donor site had infection, which healed after anti-inflammatory dressing changes; the remaining incisions healed by first intention, and the grafts survived smoothly. All patients were followed up 8-36 months (median, 21 months). The repaired facial appearance was satisfactory, with no flap swelling. Among the patients underwent postoperative radiotherapy, 2 patients had normal bone healing and 1 had delayed healing at 6 months.
UNASSIGNED: In free fibular flap reconstruction of mandibular defects, the use of mixed reality technology for perforator vessel localization can achieve three-dimensional visualization, simplify surgical procedures, and reduce errors.
UNASSIGNED: 探讨在游离腓骨皮瓣修复下颌骨缺损中，使用混合现实技术定位穿支血管的可行性和效果。.
UNASSIGNED: 2020年6月—2023年6月，采用游离腓骨皮瓣修复12例下颌骨缺损患者。男8例，女4例；年龄35～78岁，平均61岁。下颌骨成釉细胞瘤9例，侵犯下颌骨口腔鳞癌3例。病程15 d～2年，中位病程14.2个月。下颌骨缺损长度5～14 cm，平均8.5 cm；软组织缺损范围为5 cm×4 cm～8 cm×6 cm。术前均行颌面部增强CT和下肢CT血管造影检查，将所得数据制成下颌骨、下肢穿支血管三维模型。术中使用混合现实技术将穿支血管三维模型重叠于患者体表，制取游离腓骨皮瓣修复缺损。腓骨切取长度为6～15 cm，平均9.5 cm；皮瓣切取范围6 cm×5 cm～10 cm×8 cm，供区拉拢缝合（7例）或游离植皮修复（5例）。.
UNASSIGNED: 12例患者术前使用混合现实技术定位穿支血管30支，每例平均2.5支；术中测量术前定位穿支血管穿出点与实际穿出点距离为1～4 mm，平均2.8 mm。术后12例腓骨瓣顺利成活；1例皮瓣远端边缘坏死，换药后延期愈合。供区发生感染1例，经抗炎换药治疗后愈合；其余患者切口Ⅰ期愈合，植皮顺利成活。患者均获随访，随访时间8～36个月，中位时间21个月。修复面部外形好，皮瓣无臃肿。3例术后接受放化疗患者中，随访6个月时2例正常骨愈合、1例延迟愈合。.
UNASSIGNED: 在游离腓骨皮瓣修复下颌骨缺损手术中使用混合现实技术，可以实现穿支血管三维可视化，手术操作简便，误差较小。.

The Alberta reconstructive technique (ART) is an innovative surgical procedure performed on patients undergoing primary jaw resection and reconstruction. The ART procedure was developed in collaboration with the Institute for Reconstructive Sciences in Medicine and the Division of Otolaryngology-Head and Neck Surgery, University of Alberta.

BACKGROUND: Ossifying fibromas are rare, non-aggressive benign tumours of the bone, commonly involving the posterior mandible in middle-aged individuals with a female predilection.
RESULTS: Clinical manifestations include asymptomatic expansion of the mandible with infrequent maxillary lesions, pain, malocclusion, and compromised quality of life including aesthetic perception. Owing to multiplicity of features, tendency of recurrence, and possibility of malignant transformation, the diagnosis, treatment, and post-operative management of ossifying fibroma are always a challenge.
UNASSIGNED: Study aims to report a clinical case of extensive swelling involving the coronoid process and condyle on the right side to crossing the mid-line of the mandible with compromised functions and aesthetics. The article describes the clinical, histopathological, and radiological features of the case. The possible treatment and challenges encountered are discussed.

BACKGROUND: Currently, the differentiation of jaw tumors is mainly based on the lesion\'s morphology rather than the enhancement characteristics, which are important in the differentiation of neoplasms across the body. There is a paucity of literature on the enhancement characteristics of jaw tumors. This is mainly because, even though computed tomography (CT) is used to evaluate these lesions, they are often imaged without intravenous contrast. This study hypothesised that the enhancement characteristics of the solid component of jaw tumors can aid in the differentiation of these lesions in addition to their morphology by dual-energy CT, therefore improving the ability to differentiate between various pathologies.
OBJECTIVE: To evaluate the role of contrast enhancement and dual-energy quantitative parameters in CT in the differentiation of jaw tumors.
METHODS: Fifty-seven patients with jaw tumors underwent contrast-enhanced dual-energy CT. Morphological analysis of the tumor, including the enhancing solid component, was done, followed by quantitative analysis of iodine concentration (IC), water concentration (WC), HU, and normalized IC. The study population was divided into four subgroups based on histopathological analysis-central giant cell granuloma (CGCG), ameloblastoma, odontogenic keratocyst (OKC), and other jaw tumors. A one-way ANOVA test for parametric variables and the Kruskal-Wallis test for non-parametric variables were used. If significant differences were found, a series of independent t-tests or Mann-Whitney U tests were used.
RESULTS: Ameloblastoma was the most common pathology (n = 20), followed by CGCG (n = 11) and OKC. CGCG showed a higher mean concentration of all quantitative parameters than ameloblastomas (P < 0.05). An IC threshold of 31.35 × 100 μg/cm3 had the maximum sensitivity (81.8%) and specificity (65%). Between ameloblastomas and OKC, the former showed a higher mean concentration of all quantitative parameters (P < 0.001), however when comparing unilocular ameloblastomas with OKCs, the latter showed significantly higher WC. Also, ameloblastoma had a higher IC and lower WC compared to \"other jaw tumors\" group.
CONCLUSIONS: Enhancement characteristics of solid components combined with dual-energy parameters offer a more precise way to differentiate between jaw tumors.

UNASSIGNED: This study aims to evaluate the factors most associated with early and late complications following microvascular free tissue transfer (MVFTT) after mandibulectomy.
UNASSIGNED: A retrospective review of patients undergoing MVFTT after segmental mandibulectomy from September 2016 to February 2021 was performed across a single academic institution. Surgical variables were collected, including the location of the resultant mandibular defect (anterior vs posterior) and flap type (osseous or non-osseous). The primary outcome variables included postoperative complications (early, <90 days; and late, >90 days) and the patients\' functional status (return to oral intake). Descriptive statistics, chi-square test, Fischer\'s exact test, and 2-sample t tests were used to analyze differences among variables.
UNASSIGNED: We analyzed a cohort of 114 consecutive patients with mandibular defects, comprising 57 anterior and 57 posterior defects. Bony free flaps with hardware were used to reconstruct 98% of anterior defects compared to 58% of posterior defects (P < .001). All soft tissue only flaps did not utilize any hardware during the reconstruction. Anterior defects demonstrated more late complications requiring additional surgery (30% vs 9%, P = .04). A secondary analysis of posterior mandibular reconstructions compared soft tissue only flaps and bony free flaps with hardware and showed equivalent rates of early (12% vs 13%, P > .99) and late (9% vs 8%, P > .99) complications requiring additional surgery while demonstrating a similar return to full oral competence (55% vs 46%, P = .52) and recovery of a 100% oral diet (67% vs 54%, P = .53).
UNASSIGNED: Osseous free tissue transfer for segmental mandibular defects remains the gold standard in reconstruction. In our patient cohort, anterior mandibular defects are associated with greater late (>90 day) complications requiring additional surgery. Comparable outcomes may be achieved with soft tissue only versus osseous free flap reconstruction of posterior mandibular defects.