Solitary primary intraosseous xanthoma of the mandible in a 15-year-old boy: a case report.

BACKGROUND: A xanthoma is a rare bone condition consisting of a predominant collection of lipid-rich, foamy histiocytes. The central xanthoma of the jaws is a unique benign tumor. CASE REPORT: A 15-year-old Caucasian male has been presented to our department. He had radiological changes in the area of the left mandibular angle, with an area of diffuse osteolysis of 3.0 cm by 2.0 cm. Computed tomography reveals an area of diffuse osteolysis that starts from the distal root of the lower second molar and reaches the ascending process. A bone biopsy was performed, which revealed a benign proliferative process composed of histiocytic cells involving and infiltrating trabecular bone in a background of loose fibrous connective tissue devoid of any other significant inflammatory infiltrate. The size of the formation was 2.9 cm by 2.0 cm. Immunohistochemical staining for CD68 was strongly positive and negative for S-100 and CD1a. From routine blood tests, cholesterol, triglycerides, and blood sugar are within normal values, which excludes systemic metabolic disease. Subsequent to the surgical intervention, the patient underwent postoperative assessments at intervals of 14, 30, 60 days, and a year later, revealing the absence of any discernible complications during the aforementioned observation periods. CONCLUSION: The diagnosis of primary xanthoma of the mandible is rare and can often be confused with other histiocytic lesions. A differential diagnosis should be made with nonossifying fibroma and Langerhans cell histiocytosis, as in our case. In these cases, immunohistochemistry with CD 68, S-100, and CD1a, as well as blood parameters, are crucial for the diagnosis.

Recurrence of Glandular Odontogenic Cysts: A Systematic Review.

BACKGROUND: The glandular odontogenic cyst (GOC) is a benign developmental cyst of the jaws that is characterized by a high recurrence rate. METHODS: A systematic review is presented of reported cases, case series, and retrospective studies of recurrent cases of glandular odontogenic cysts, to determine the overall and detailed demographic features with documentation of the specific histologic features of the initial presentation of each cyst. Searches of detailed databases were carried out to identify articles published in the English language from 1988 to 2023. The variables were demographics, patient symptoms, cyst location, radiographic features, histopathological findings, type of treatment, and minimum eight months of follow-up. RESULTS: Eighteen cases were identified: with an equal gender presentation of 50% females and 50% males. The average age was 44.7. The mean size was 3.5 cm. The most common location was in the anterior mandible in 50% (n = 9) of cases, followed by the posterior mandible 27.8% (n = 5). Most patients were asymptomatic 55.6% (n = 10). The most common histologic features at first diagnosis were mucous cells in 88.9% (n = 16), variable thickness with 83.3% (n = 15), eosinophilic cuboidal cells 88.9% (n = 16), microcysts 83.3% (n = 15), and clear cells 77.8% (n = 14) cases. CONCLUSION: GOC has an aggressive behavior. Evidence was not conclusive to link any single or combination of histologic features to recurrence, and the strongest correlation for recurrence was the type of treatment. Since this is an uncommon cyst, more cases are needed. Follow-up should continue for at least five years, because recurrences were higher between years 3 and 5.

Recurrent cementoblastoma with multifocal growth and cellular atypia: a case report.

BACKGROUND: Cementoblastoma is a rare odontogenic tumor characterized by the formation of osteocementum-like tissue on a tooth root directly by neoplastic cementoblasts. Although it is categorized as benign, it has a high potential for growth with a certain degree of recurrence risk. However, there are only a few studies describing the features of recurrent cementoblastoma. The diagnosis of recurrent cementoblastoma is challenging not only due to its cytological atypia but also because of its large size and multicentric growth pattern. These characteristics suggest a potential for malignancy. CASE PRESENTATION: A 29-year-old woman was transferred to our university dental hospital complaining of swelling of the right mandible. She had a history of enucleation of cementoblastoma associated with the third molar of the right mandible. Five years after the initial treatment, imaging demonstrated well-circumscribed multicentric radiopaque lesions in the same area. Histologically, the lesion consisted of osteocementum-like tissue rimmed with polygonal or plump tumor cells. Several cells were large epithelioid cells with bizarre nucleoli, which may be reminiscent of malignant tumors. Otherwise, there were no apparent malignant findings, including proliferative activity or atypical mitotic figure. Besides, tumor cells were positive for c-FOS, a marker of osteoblastoma and cementoblastoma. Eventually, the patient was diagnosed with recurrent cementoblastoma. CONCLUSIONS: Pathological analyses of this case suggested that the recurrent event in the cementoblastoma altered its growth pattern and tumor cell shape. Moreover, in the case of enucleation surgery, long-term follow-up is important because there is some recurrent risk of cementoblastoma, although it is not high.

[Analysis of surgical approaches and mandibular treatment strategies for different types of tumors involving parapharyngeal space].

In view of the surgical complexity of parapharyngeal space tumors involved, this paper summarized the disease data of patients with parapharyngeal space tumors involved in the Department of Oral and Maxillofacial Surgery, the First Hospital of Shanxi Medical University from January 2015 to January 2021. It also summarized the surgical approach and mandibular management, so as to explore surgical strategies for different characteristics of parapharyngeal space tumors involved. A total of 49 patients, including 28 males and 21 females, median age 52 years (range 24-72 years). They were treated with four surgical approaches for tumor resection, 25 cervical approach, 5 cheek and neck approach, 3 transoral approach, and 16 cervical-maxillary approach. Among the patients treated with cervical-maxillary approach, 3 patients were treated with mandible square resection, and 6 patients were treated with temporary mandible dissection. Seven cases were treated with tumor resection and partial mandibular resection. There are various surgical approaches and mandibular management methods involving tumors in the parapharyngeal space, and clinical decisions should be made based on tumor diameter, location, boundary, blood supply and pathological types.

Glandular odontogenic cyst: Review of literature and report of two cases.

Glandular odontogenic cyst (GOC) is a rare developmental odontogenic cyst from the cell rests of Serres. GOC is locally aggressive with a tendency toward recurrence. The most common site of occurrence is the anterior mandible with an asymptomatic presentation. Radiographically, it presents as unilocular or multilocular radiolucency. It bears histopathological resemblance to low-grade mucoepidermoid carcinoma. We report two cases of GOC occurring in a 16-year-old and a 33-year-old male patient with a review of the clinical presentation, histopathological features, and diagnostic aspects of GOC reported so far in literature.

Central giant cell granuloma of the jaws-long-term clinical and radiological outcomes of surgical and pharmacological management.

OBJECTIVES: To compare long-term results of different treatment modalities in central giant cell granuloma of the maxillofacial-skeleton. Primary resection may result in major defects. Alternative treatments include pharmacological agents. As yet there has been no consensus on the use of the variety of treatment options, and few studies have reported clarifying long-term results. MATERIALS AND METHODS: This retrospective study on 22 patients with 25 lesions evaluated clinical, radiological and histological features, treatment preformed and lesion recurrence. Success was defined as regression/calcification and failure as recurrence, progression or un-responsiveness. RESULTS: Of the presenting patients, 77% were under age 40. Lesion prevalence was higher in the anterior mandible and left posterior maxilla. Most cases exhibited pain, tooth-mobility or mucosal-expansion. The appearance was predominantly unilocular in the maxilla and multilocular in the mandible, which also exhibited higher prevalence of cortical perforation. Up to 80% of lesions were classified as aggressive. Intralesional steroids/calcitonin were used in 7 cases. Mean follow-up was 39.8 months. Two cases showed recurrence. In 71% of the cases treated pharmacologically, calcification/regression were observed. CONCLUSIONS: Our analysis indicates better outcomes using a combined approach, including both pharmacological and surgical treatments in large aggressive lesions. Pharmacological treatment resulted in decreased size or well-defined lesions, thus reducing the need for extensive bone resection. Dual treatment with corticosteroids and calcitonin showed no superior outcomes, but a larger cohort should be assessed. CLINICAL RELEVANCE: There are several protocols for treatment of central-giant-cell-granuloma lesions, but most are not fully established. It is important to report results that contribute to the establishment of proven protocols. This report attempts to establish the relevance of the combined approach: pharmacological treatment followed by surgical resection.

Xanthoma of the Jaw Bones: Cases Series and Review of Literature.

BACKGROUND: Intraosseous xanthomas are rare benign lesions sometimes associated with excess lipid production. Xanthoma of the jaw bones (XJB) was first reported in 1964, and fewer than 50 cases have been reported in the English literature to date. The etiopathogenesis of XJB is highly suggestive of a reactive process or a metabolic condition. METHOD: Seven cases of XJBs were retrieved from the archives of 4 oral and maxillofacial pathology services. Clinical, radiographic and histopathologic features of all these cases were retrospectively analyzed. Immunohistochemical (IHC) stains for S100 and CD68 were performed. RESULTS: All seven cases involved the mandible. Patients' age ranged between 13 and 69 years with an evenly distributed female to male ratio. One patient had a medical history of hyperlipidemia, but the medical and dental histories of the others were unremarkable. For most cases, XJB was an incidental finding discovered during routine radiographic examination. Swelling and cortical expansion were noted in a few cases. Radiographically, cases typically presented as either well-defined multilocular or unilocular lesions, which were either radiolucent or mixed radiolucent/radiopaque. All the lesions were treated with surgical curettage and no recurrence was observed during subsequent follow-ups. Each of the seven cases exhibited sheets of foamy macrophages. The diagnosis is established by exclusion of entities with overlapping microscopic features and involved correlation with the clinical, histological, radiographic and IHC profiles. Immunohistochemically, all the cases expressed diffuse positivity for CD68 and were negative for S100. CONCLUSION: XJB is a rare lesion of unknown etiology, which may mimic other benign or reactive jaw lesions. Due to its rarity and the potential diagnostic challenges it presents, clinicians must remain vigilant and consider CXJ in their differential when assessing radiolucent jaw anomalies.

Prevalence of impacted third molars: a radiographic study among a North African population.

INTRODUCTION: Third molars are the most commonly concerned teeth with the impaction. Impacted third molar (ITM) can be associated to various clinical pathologies Aim: To determine the prevalence of ITM, its pattern and associated affections in Tunisian patients. METHODS: The study reviewed panoramic radiographs of patients consulting the Fattouma Bourguiba University Hospital, Monastir (Tunisia). Orthopantomograms were analyzed to define the prevalence of ITM; its angulation, depth and relation with the anterior border of mandibular ramus. Associated pathologies were also assessed. RESULTS: Seven hundred and thirty patients were included (286 men and 444 women). The age ranged from 19 to 89 years. Half of the patients (50.3%) showed at least one ITM. The total number of ITM was 881 with a statistical difference between arches (respectively 34.3% and 65.7% in the maxilla and in the mandible). The most common number of ITM was two (35.4%). Level C of impaction was observed more frequently in the maxilla and level A in the mandible. The most common angulation was the vertical one for both arches. Seventy six percent of ITM were presented with class II in relation with the anterior border of mandibular ramus. There was no significant difference in the frequency of impaction between gender and sides. The number of ITM associated with pathological conditions was 199 (22.6%). The most frequently observed pathology was the distal caries on the second molars (11.7%) followed by the caries of the third molars (5.2%). CONCLUSION: The prevalence of ITM among Tunisian patients was high.

Lateralization of the Inferior Alveolar Nerve in the Rehabilitation of Mandibular Atrophy: Case Report.

The lateralization of the inferior alveolar nerve, or LIAN procedure, may be a surgical consideration for implant-prosthetic rehabilitation in the edentulous mandibular posterior region. This technique can be advantageous in that it does not require a donor site and allows for the immediate placement of an implant, potentially leading to reduced morbidity, healing time, and costs. Although such risks as altered sensory nerve function and weakening of the mandibular body are associated with the LIAN procedure, it is a viable alternative to various regenerative techniques to rehabilitate a patient with an implant-supported fixed prosthesis.

Ameloblastic carcinoma: A systematic review.

BACKGROUND: Ameloblastic carcinoma (AC) is the most common odontogenic malignancy, constituting approximately 30% of cases in this category. Literature is sparse on malignant odontogenic neoplasms, with a large proportion of current knowledge derived from case reports or small case series. METHODS: A systematic review of case series/case reports of AC was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) Statement guidelines. Demographic and clinical information, including duration of the lesion, location, clinical presentation and radiologic features, were analysed. Additionally, the origin of the lesion (primary/secondary), Ki-67 proliferation index, treatment performed, metastasis, tumour recurrence and prognosis were collected for analysis. RESULTS: A total of 126 studies, including 285 individual cases of AC, were included in this review. Patients presented with a near-equal distribution of painless and painful swellings. ACs presented at a median age of 45 years, with a male-to-female ratio of 1:2. The mandible was most frequently involved, with rare cases extending to involve more than one region, including crossing the midline. Although most lesions presented with poorly-demarcated borders (52.6%), unilocular lesions with well-demarcated borders (47.4%) comprised a substantial number in the sample. The proliferation index was only reported in 27 cases, with a mean score of 42% and a wide range. The probability of tumour recurrence increased, and the survival probability decreased with prolonged follow-up duration. CONCLUSION: This study provides more comprehensive, up-to-date descriptive data on these rare odontogenic malignancies, aiding clinicians and Pathologists with the diagnosis and surgeons in their management of cases.

Unraveling the challenges in the diagnosis and management of desmoplastic fibroma of the mandible-a case report.

Desmoplastic fibroma (DF) is an uncommon bone tumor that originates from the mesenchymal tissue and despite being benign, exhibits aggressive behavior locally. The following report describes the case of a 7-year-old boy with a rapidly enlarging swelling on the right side of the mandible. After a thorough clinical examination, radiographic imaging, and histopathological analysis, the diagnosis of DF was confirmed. Treatment planning was formulated considering both the tumor's tendency for local recurrence and the patient's well-being. Due to the patient's young age, segmental resection was not deemed appropriate, and an aggressive curettage and enucleation of the lesion followed by the bone graft was performed instead. The patient was kept under close follow-up for the first month of post-surgery and later reviewed after 3, 6, 9, and 12 months, respectively. Good bone healing was observed on radiographs. The patient did not show any signs of recurrence based on clinical or radiographic assessments and did not exhibit any neurosensory deficits as well.

Clinical characteristics and surgical management of facial infiltrating lipomatosis: a single center experience.

BACKGROUND: Facial infiltrating lipomatosis (FIL) is a rare condition characterized by congenital facial enlargement. Beyond its impact on physical appearance, FIL can also impair essential facial functions such as swallowing, chewing, vision, and breathing, imposing a substantial physiological and psychological burden. Currently, fewer than 80 cases of FIL have been reported, and the characteristics and management strategies for FIL remain unclear. METHODS: We reviewed the clinical, surgical, and radiological records of 39 FIL patients who were treated at our center. Of these, genetic testing was performed for 21 patients. RESULTS: Aberrant overgrowth involves subcutaneous fat, bones, muscles, glands, tongue, lips, and teeth. Epidermal nevi could be observed in the dermatomes innervated by the three branches of the trigeminal nerve, with the highest frequency seen in the dermatome of the mandibular branch. Four patients exhibited concurrent hemimegalencephaly (HMEG), with one case presenting HMEG on the opposite side of the FIL. Nineteen patients were confirmed to harbor the PIK3CA mutation. Thirty-three patients underwent surgical procedures, with a post resection recurrence rate of approximately 25%. CONCLUSIONS: A variety of maxillofacial structures may be involved in FIL. PIK3CA mutations are important pathogenic factors. Emerging targeted therapies could present an additional treatment avenue in the future. However, surgery currently remains the predominant treatment choice for FIL. The timing and modality of surgery should be individually customized, taking into account each patient's unique circumstances. Notably, there is a significant possibility of postoperative recurrence during childhood and adolescence, necessitating early strategic planning of disease management.

Computed tomography/magnetic resonance imaging for mandibular boundary invasion of oral squamous cell carcinoma assessment.

BACKGROUND: The range of mandibular invasion by a tumour needs to be determined accurately to minimize unnecessary damage to the mandible. This study aimed to compare tumour boundary lines on computed tomography/magnetic resonance (CT/MR) images with those from pathological findings during the preoperative assessment of mandibular invasion by oral squamous cell carcinoma (OSCC). By comparing the methods, the potential of CT/MR for this application could be further elucidated. METHODS: Eight patients with OSCC were imaged with CT/MR, mandibular specimens were collected, and the material site was measured. Haematoxylin-eosin staining was used for histopathological assessment. The presence and boundaries of bone invasion were evaluated. The CT/MR and histopathological boundaries of bone invasion were delineated and merged to compare and calculate the deviation of CT/MR and histopathological boundaries using the Fréchet distance. RESULTS: The mean Fréchet distance between the CT and pathological tumour boundaries was 2.69 mm (standard error 0.46 mm), with a minimum of 1.18 mm, maximum of 3.64 mm, median of 3.10 mm, and 95% confidence interval of 1.40-3.97 mm. The mean Fréchet distance between the tumour boundaries on the MR and pathological images was 3.07 mm (standard error 0.56 mm), with a minimum of 1.53 mm, maximum of 4.74 mm, median of 2.90 mm, and 95% confidence interval of 1.53-4.61 mm. CONCLUSIONS: CT/MR imaging can provide an effective preoperative assessment of mandibular invasion of OSCC. Pathology images can be positioned on CT/MR scans with the help of computer software to improve the accuracy of the findings. The introduction of the Fréchet distance to compare tumour boundary lines is conducive to computer image diagnosis of tumour invasion of jaw boundaries.

Three-dimensional analysis of mandibular morphology asymmetry and temporomandibular joint position in patients with unilateral Brodie bite.

OBJECTIVE: Previous studies have shown unilateral posterior crossbite is associated with mandibular asymmetry in morphology and position. However, it remains unclear whether unilateral Brodie bite plays a similar role in mandibular development. Therefore, this study aims to investigate the morphological and positional symmetry of mandibles in patients with unilateral Brodie bite by three-dimensional anaylsis. METHODS: Fourteen patients with unilateral Brodie bite (mean age 18.43 ± 4.24 years) and fourteen sex- and age-matched patients with normal occlusion (mean age 18.07 ± 5.48 years) underwent cone-beam computed tomography (CBCT) scans. 3D surface mesh models of their mandibles were established using Mimics Research 19.0. The surface matching percentage was compared between the original and mirrored mandible by Geomagic Control X software. Furthermore, the dimension and position of the temporomandibular joint (TMJ) were determined for both groups using InVivoDental 5.0. RESULTS: For surface-to-surface deviation analysis, the percentage of mismatch in patients with unilateral Brodie bite was significantly higher than the control group at ±0.50 mm, ±0.75 mm, and ±1.00 mm tolerance (P < .001). In patients with unilateral Brodie syndrome, the condyles on the scissors-bite side showed a significantly more anterior position (P = .03), greater medial inclination (P < .01), and larger posterior TMJ space (P = .01) than the non-scissors-bite side. CONCLUSION: Patients with unilateral Brodie bite exhibit a more asymmetrical mandibular morphology, with a greater anterior condylar position and posterior joint space on the scissors-bite side, indicating that early diagnosis and treatment may be necessary for patients with unilateral Brodie bite.

Long-term follow-up of osteoradionecrosis of the mandible.

AIM: Investigating the prevalence of mandibular ORN in a single Swedish Oncology Center. METHODS: A total of 450 patients, treated with radiotherapy for squamous cell carcinoma in the oropharynx between 2004 and 2014 were included. Three different techniques of radiotherapy were studied. ORN diagnosis was set when clinical signs according to Marx were observed, or if radiological signs were staged according to Schwartz and Kagan. RESULTS: Using the staging system, 90 patients (20%) were diagnosed with ORN. The mean age of the ORN patients was 56.6 years, the older the patient the lower the risk of developing ORN (p = .01). The risk of developing ORN for patients receiving Intensity Modulated Radiotherapy was lower compared to patients treated with the other techniques in the multivariable analysis. Brachytherapy significantly increases the risk of ORN. The risk of ORN increased by 8% each year after radiation (p = .04). The mean time to the ORN diagnosis was 3.9 years. In the multivariate analysis, the risk of ORN increased by 13% each year after radiation (p = .0013). CONCLUSION: The mean radiation dose was of greater importance for the risk of ORN than the maximum dose. Elderly people with oropharyngeal cancer were less prone to develop ORN.

A case of radicular cyst on deciduous tooth in a 7-year-old child.

Radicular cysts are the most common cystic lesions in the oral cavity, and have a rare occurrence in the primary dentition. We report a case of radicular cyst of mandible in child by multimodal imaging including panoramic radiography, CT, and MR imaging. A 7-year-old girl presented with swelling and without pain, and hypoesthesia on the right side of the mandible. On clinical examination, an expansive lesion with undulation was found to the buccal cortex of the right side of the mandible. Panoramic radiograph showed a unilocular radiolucency with well-defined margin, displaced tooth, and root resorption in the right mandible. Regarding CT imaging, axial soft tissue algorithm CT and bone tissue algorithm CT showed a low-attenuation internal structure and expansion of the buccal cortex of the right side of the mandible. Three-dimensional-CT showed expansion of the buccal cortex of the right side of the mandible. Multiplanar reformation imaging showed displaced tooth, root resorption, and expansion of the buccal cortex of the right side of the mandible. On T1-weighted image, the expansive lesion showed low signal intensity, and T2-weighted and STIR images revealed high signal intensity. A partial biopsy of the mandibular region was performed. Histopathological diagnosis was radicular cyst caused by apical periodontitis with abscess. This case suggests that multimodal imaging, especially CT and MR imaging, could be effective for evaluating mandibular lesions in child.

Pathological mandibular fracture complicated by osteonecrosis in an adult patient with pycnodysostosis: clinical report and review of the literature.

Pycnodysostosis is an ultra-rare osteosclerotic skeletal disorder characterized by short stature, susceptibly to fractures, acroosteolysis of the distal phalanges, and craniofacial features (frontal bossing, prominent nose, obtuse mandibular angle, micrognathia). Dental abnormalities (delayed eruption of teeth, hypodontia, malocclusion, dental crowding, persistence of deciduous teeth, enamel hypoplasia, and increased caries) are also frequent; due to bone metabolism alteration, the patients have an increased risk for jaw osteomyelitis, especially after tooth extraction or mandible fracture. Other complications are obstructive sleep apnea, endocrine alterations and cytopenia. Pycnodysostosis is caused by biallelic loss of function variants in CTSK gene, coding the lysosomal protease cathepsin K. CTSK is involved in the degradation of bone matrix proteins, such as type I and type II collagen. In pycnodysostosis, this degradation is decreased, leading to increased bone density and bone fragility with pathological fractures and poor healing. We present a clinical report of a female adult patient with typical pycnodysostosis phenotype. At the age of 52 years, she had a pathological spontaneous fracture of the right mandible complicated by osteonecrosis, treated with load bearing osteosynthesis. The direct sequencing of CTSK gene revealed the presence of the pathogenic homozygous variant c.746T>A, (p.Ile249Asn), that confirmed the diagnosis of pycnodysostosis. We also review the literature case series published to date, that suggest to always consider the diagnosis of pycnodysostosis in case of osteosclerosis, even in the absence of brachydactyly or short stature. This report details the natural history of the disease in this patient, from childhood to adulthood, and highlights the importance of a quality of life assessment. In addition, we describe a case of mandibular osteonecrosis and spontaneous fracture in pycnodysostosis, drawing attention on the maxillofacial complications in these patients and on the importance of a personalized follow-up.

Bone regeneration in critical-size defects of the mandible using biomechanically adapted CAD/CAM hybrid scaffolds: An in vivo study in miniature pigs.

The study aimed to analyze bone regeneration in critical-size defects using hybrid scaffolds biomechanically adapted to the specific defect and adding the growth factor rhBMP-2. For this animal study, ten minipigs underwent bilateral defects in the corpus mandibulae and were subsequently treated with novel cylindrical hybrid scaffolds. These scaffolds were designed digitally to suit the biomechanical requirements of the mandibular defect, utilizing finite element analysis. The scaffolds comprised zirconium dioxide-tricalcium phosphate (ZrO2-TCP) support struts and TCP foam ceramics. One scaffold in each animal was loaded with rhBMP-2 (100 µg/cm³), while the other served as an unloaded negative control. Fluorescent dyes were administered every 2 weeks, and computed tomography (CT) scans were conducted every 4 weeks. Euthanasia was performed after 3 months, and samples were collected for examination using micro-CT and histological evaluation of both hard and soft tissue. Intravital CT examinations revealed minor changes in radiographic density from 4 to 12 weeks postoperatively. In the group treated with rhBMP-2, radiographic density shifted from 2513 ± 128 (mean ± SD) to 2606 ± 115 Hounsfield units (HU), while the group without rhBMP-2 showed a change from 2430 ± 131 to 2601 ± 67 HU. Prior to implantation, the radiological density of samples measured 1508 ± 30 mg HA/cm³, whereas post-mortem densities were 1346 ± 71 mg HA/cm³ in the rhBMP-2 group and 1282 ± 91 mg HA/cm³ in the control group (p = 0.045), as indicated by micro-CT measurements. The histological assessment demonstrated successful ossification in all specimens. The newly formed bone area proportion was significantly greater in the rhBMP-2 group (48 ± 10%) compared with the control group without rhBMP-2 (42 ± 9%, p = 0.03). The mean area proportion of remaining TCP foam was 23 ± 8% with rhBMP-2 and 24 ± 10% without rhBMP-2. Successful bone regeneration was accomplished by implanting hybrid scaffolds into critical-size mandibular defects. Loading these scaffolds with rhBMP-2 led to enhanced bone regeneration and a uniform distribution of new bone formation within the hybrid scaffolds. Further studies are required to determine the adaptability of hybrid scaffolds for larger and potentially segmental defects in the maxillofacial region.

Microstructural changes in the irradiated and osteoradionecrotic bone: a SEM study.

Radiation exposure is a major health concern due to bone involvement including mandible, causing deleterious effects on bone metabolism, and healing with an increasing risk of infection and osteoradionecrosis. This study aims to investigate the radiotherapy-induced microstructural changes in the human mandible by scanning electron microscopy (SEM). Mandibular cortical bone biopsies were obtained from control, irradiated, and patients with osteoradionecrosis (ORN). Bone samples were prepared for light microscopy and SEM. The SEM images were analyzed for the number of osteons, number of Haversian canal (HC), diameter of osteon (D.O), the diameter of HC (D.HC), osteonal wall thickness (O.W.Th), number of osteocytes, and number of osteocytic dendrites. The number of osteons, D.O, D.HC, O.W.Th, the number of osteocytes, and osteocytic dendrites were significantly decreased in both irradiated and ORN compared to controls (p < .05). The number of HCs decreased in irradiated and ORN bone compared to the control group. However, this was statistically not significant. The deleterious effect of radiation continues gradually altering the bone quality, structure, cellularity, and vascularity in the long term (>5 years mean radiation biopsy interval). The underlying microscopic damage in bone increases its susceptibility and contributes further to radiation-induced bone changes or even ORN.