Sexual Dimorphism in Adult Human Mandible of North Indian Origin

Background: In forensic science the identification of a human is based on three important factors: Age, Sex and Stature. Bones are an important tool for it and among human bones the pelvis and the skull are the most reliable source for sex determination. In the absence of complete pelvis, mandi-ble becomes the important source for sex determination since mandible is the most durable and movable part of skull that can resist postmortem changes. The present study is conducted to assess the accuracy and role of few metric and morphological parameters in determination of the sex of dry adult human mandible of North Indian origin. Material & Methods: The Study is conducted on 50 dry intact human adult mandibles of North Indian origin. The metric parameters i.e. bigonial breadth, bicondylar breadth are measured with a Vernier Calliper by two observers. Non-metric parameters being observed are the morphological features like gonion flaring, muscular markings and shape of angle of symphysis menti. Result & Conclusion: It is concluded that bigonial breadth and bicondylar breadth exhibit the sexual dimorphism. Morphological Parameters: Gonion flaring, muscular markings and shape of angle of symphysis menti also demonstrate the sexual dimorphism. These parameters taken together may determine the sex of adult human mandibles. The present study shows that the mandible is an important tool in the determination of gender with high accuracy.

Fanconi anemia manifesting as a squamous cell carcinoma of the mandible: a case report

Progressive bone marrow failure and development of malignancies, particularly acute myeloid leukemia and solid tumors the most important features of Fan- coni’s Anemia (FA). This paper reports the case of a 16-year-old patient with FA who developped squa- mous cell carcinoma of the mandible, ten years after the bone marrow transplantation (BMT).

Osteoblastoma of the mandible: a case report with immunohistochemical evaluation

Background: Osteoblastoma, a rare osteoblastic tumor, constitutes approximately 1% of all primary bone tu- mors. Aim: The purpose of this report is to present an osteoblastoma of the mandible, with particular emphasis on the differential diagnosis of this rare tu- mor. Methods-Results: the lesion showed osteoblast- like cells, stromal cells, osteoclast-like cells and inter- lacing trabeculae of osteoid. Because of the high cel- lularity of the tumor, immunohistochemical analysis was performed using the cell proliferation marker Ki-67, the p53 and the anti-apoptotic protein Bcl-2. The lesion demonstrated low to moderate prolifera- tive activity and no immunoreactivity was detected for p53. An interesting finding was the Bcl-2 expres- sion by the multinucleated osteoclast-like giant cells, in contrast to the lack of Bcl-2 expression from osteo- blast-like and stromal tumor cells. Conclusion: To our knowledge the Bcl-2 expression has not yet been in- vestigated in benign or malignant osteoblastic tumors. This finding may be related to the molecular mecha- nisms regulating the apoptosis of osteoclast-like tu- mor cells or their function.

Single Nucleotide Polymorphisms and Haplotypes in Vascular Endothelial Growth Factor Gene and Residual Ridge Resorption of Mandible in Korean Population

The tooth extraction is a routine surgical procedure in the dental treatment where the healing process results in a saddle-shaped residual ridge in the edentulous jaw. There are substantial differences among individuals in the end result. In some cases, there is excessive bone atrophy, which complicates the dental restorative treatment. The alveolar ridge receives the mechanical load continuously from the periodontal ligament connected to the teeth and it diminishes dramatically as a consequence of dental extraction;thus it is believed the continuing pattern of the alveolar bone resorption is related to this change. The reduced partial pressure of oxygen is the most prominent event from the reduced mechanical load. Vascular Endothelial Growth Factor (VEGF), regulated by HIF-1, reported close association with angiogenesis and bone turn over, where partial oxygen pressure has changed. Therefore the genetic association between Single Nucleotide Polymorphsim (SNP) of VEGF gene and RRR was investigated. 120 subjects (70.93 ± 9.28 years) which were treated at Dental clinic of Yonsei University with edentulous mandible were recruited. Mandibular bone height was measured following the protocol of the American College of Prosthodontists. Three variants, rs1570360, rs25648, and rs3025039 in VEGF from previous study, were used as tag-SNPs and genotyping for the study. Student’s t-test and ANOVA were used for statistical analysis. There was a notable association with rs1570360 (P = 0.051) in dominant group and haplotype A-C-C showed a statistically significant association with RRR in dominant group (P = 0.042). Results of this study may be useful in developing novel genetic diagnostic tests and identifying Koreans susceptible to developing severe RRR after dental extraction.

Sexual Dimorphism in the Mandible Shape of <i>Neospondylis upiformis</i>(Coleoptera: Cerambycidae)

Sexes of adult Cerambycidae (Coleoptera) are usually discriminated by the greater length of male antennae. However, in Spondylidinae, adult antennae are short and the difference between sexes is negligible and difficult to appraise. Only two species belong to this subfamily in North America, one of these being Neospondylis upiformis (Mannerheim), a species rarely caught in eastern North America. Unexpectedly, we collected numerous specimens of Neospondylis upiformis on Anticosti Island, Quebec, which appears as a hotspot for this species in eastern Canada. We show that sexual dimorphism in the mandible shape of N. upiformis (Mannerheim) can be used to discriminate sexes. Females have robust mandibles with a sharp cutting inner edge while males have thin mandibles and a well-rounded inner edge. There was no overlap between sexes in all measures done on mandibles, showing that mandible shape was a reliable criterion for sexing N. upiformis. We also tested previously reported criteria using antennae, as well as other characteristics such as body size, and show that they can hardly discriminate between sexes in N. upiformis. We also present illustrations of male and female genitalia, which is rarely available for Cerambycidae.

Soft tissue aneurysmal bone cyst of the mandible:Report of a case

We report the case of a 17-year-old boy with a soft tissue aneurysmal bone cyst(STABC) located in the posterior aspect of the right mandible.Conventional radiography revealed no positive findings.On the computed tomography scan,the lesion appeared to have a nonuniform intralesional density.Magnetic resonance imaging revealed an abnormal soft tissue masses with cystic component in the superficial part of right mandibular body and angle with intact cortex.Following histopathological examination,fibro-histiocytic proliferation,blood-filled spaces and multinucleated giant cells were seen and the lesion was diagnosed as a STABC.The mass together with underlying bone and periosteum on its periphery was surgically resected under general anesthesia.Thirty-six months after surgery the patient was assessed at outpatient clinic and found no sign of recurrence This may be only the first reported case of the mandible in the English literature of this extremely rare benign tumor occurring in soft tissue.

Dynamic navigation system-guided trans-inferior alveolar nerve implant placement in the atrophic posterior mandible: A case report

BACKGROUND In atrophic posterior mandibular areas,where the bone height superior to the inferior alveolar nerve(IAN)is less than 6 mm,short implants are not applicable.Conventional alternatives such as IAN transposition and various alveolar bone augmentation approaches are technically demanding and prone to complications.CASE SUMMARY Computer-guided dynamic navigation implantation improves the accuracy,predictability,and safety of implant placement.This case report presents a dynamic navigation system-guided trans-IAN implant placement technique,which can successfully treat a posterior mandibular dentition defect when the bone height is only 4.5 mm.The implant was inserted into the buccal side of the IAN and was 1.7 mm away from the IAN.The implantation deviations were controlled within a satisfying range,and the long-term restoration outcome was stable.CONCLUSION Dynamic navigation system-guided trans-IAN implant placement might be a recommended technique for patients with extremely insufficient residual bone height and sufficient bone width in the posterior mandibular area.

Solitary intraosseous neurofibroma in the mandible mimicking a cystic lesion:A case report and review of literature

BACKGROUND Neurofibromas are benign tumors of a neurogenic origin.If these tumors occur without any other signs of neurofibromatosis,they are classified as isolated neurofibromas.Neurofibromas in the oral cavity mostly occur within soft tissues,indicating that solitary intraosseous neurofibromas in the mandible are rare.Due to the absence of specific clinical manifestations,early diagnosis and treatment of these tumors are difficult to achieve.CASE SUMMARY A 37-year-old female patient visited our hospital due to numbness and swelling of the gums in the right lower molar area that had persisted for half a month.The patient’s overall condition and intraoral examination revealed no significant abnormalities.She was initially diagnosed with a cystic lesion in the right mandible.However,after a more thorough examination,the final pathological diagnosis was confirmed to be neurofibroma.Complete tumor resection and partial removal of the right inferior alveolar nerve were performed.As of writing this report,there have been no signs of tumor recurrence for nine months following the surgery.CONCLUSION This case report discusses the key features that are useful for differentiating solitary intraosseous neurofibromas from other cystic lesions.

Adipose Derived Stem Cell on the Regeneration of Irradiated Mandible of Adult Rabbit Submitted to Distraction Osteogenesis

Purpose： To evaluate the effect of adipose derived mesenchymal stem cell （ADSC） on the regeneration of irradiated mandible submitted to distraction osteogenesis on adult rabbits. Methods： Ten adult rabbits were selected and the dorsal fat was harvested for isolation, dissociation and culture of adipose derived adult mesenchymal stem cells. The mandibles were irradiated on a single dose of 20 Gy. After 30 days the animals underwent mandibular lengthening by distraction osteogenesis. After 10 mm of lengthening, the animals were distributed into two groups. Saline solution （1 mL） was injected the control group, and supplemented with ADSC, on the study group. After 4 weeks the mandibles were removed and evaluated by tomography and histomorphometric analysis. Histomorphometric was obtained and statistical analysis done by Mann-Withney test （p 〉 0.05）. Results： The tomography shows a significant improvement on the Hounsfield scale for lateral fibrovascular zone （114.5±9.7 control group to 148 ± 24, p = 0.0045） and central fibrovascular zone （37 ± 13.4 control group to 96 ±41.8 on study groupp = 0.0045）. The Histomorphometric analysis demonstrated an increase area of new bone formation. The mineralized area was of 61.2 ± 9.9% in the study group and 31.3 ± 10.6% in the control group （p = 0.0045） for the central fibrovascular zone, 79.± 9.1% in the study group and 39.1 ± 14.7 on control group for anterior fibrovascular zone （p = 0.0001） and 67.7± 12.9% in the study group and 38.4 ± 12.9% in control group for posterior fibrovascular zone （p = 0.0001）. Conclusions： The injection of adipose derived mesenchymal stem cell was effective to improve bone regeneration distraction callus on the irradiated mandible.

Angiosarcoma of the mandible: Metastasis from a primary tumor of the right atrium of the heart

Angiosarcoma of the heart is a rare tumor with very poor prognosis especially in a patient with multiple metastases. We present a case of a 39-year-old woman with angiosarcoma of the heart metastasing to the right side of the mandible, a situation not often found previously in the literature.

Cemento-ossifying fibroma of the left mandible:A case report

BACKGROUND Ossifying fibroma is a type of benign fibro-osseous lesion.Most lesions affect the mandible region,particularly the molar and pre-molar areas.It predominantly affects females between the second to fourth decades of life.Larger ossifying fibroma tumors require more extensive resection.CASE SUMMARY A 39-year-old female complained of occasional pain and tumor enlargement on her left jaw for the 3 years prior to presentation.Intraoral examination revealed a firm swelling on her left lower gum.Extraoral examination revealed swelling on the left mandible body with no erythema and superficial ulcer.Computed tomography scan revealed a circular-shaped lesion on the patient’s left mandible body with a well-defined radiolucent border,sized 3.2 cm×2.8 cm×0.9 cm.The tumor was removed by marginal mandibulectomy.Biopsy from the resected tumor suggested cemento-ossifying fibroma(COF).CONCLUSION COF is often unnoticed,but this slow-growing tumor can cause significant symptoms regarding its distortion into adjacent structures.

Stafne’s Bone Defect in Atypical Location: Between the Subcondylar Region and Neck of the Mandible Ramus

CONTEXT: Stafne’s bone defect is a benign lesion appearing on the image as a round radiolucent lesion within a cortical defect on the mandible. CASE REPORT: We attend one 46-year-old male patient came for diagnostic evaluation of a rounded and radiolucent lesion in the transition of the subcondylar region and neck of the left mandible ramus incidentally found by a dentist. Computed tomography and magnetic resonance imaging were performed in medical radiology and a Stafne’s cyst was diagnosed in an atypical location. CONCLUSION: We emphasize that Stafne’s bone defect is a benign lesion, whose imaging diagnosis can be conclusive, avoiding unnecessary surgical procedures.

Is mandible derived mesenchymal stromal cells superior in proliferation and regeneration to long bone-derived mesenchymal stromal cells?

Mesenchymal stromal cells(MSCs)are cells with the characteristic ability of self-renewal along with the ability to exhibit multilineage differentiation.Bone marrow(BM)is the first tissue in which MSCs were identified and BM-MSCs are most commonly used among various MSCs in clinical settings.MSCs can stimulate and promote osseous regeneration.Due to the difference in the development of long bones and craniofacial bones,the mandibular-derived MSCs(M-MSCs)have distinct differentiation characteristics as compared to that of long bones.Both mandibular and long bone-derived MSCs are positive for MSC-associated markers such as CD-73,-105,and-106,stage-specific embryonic antigen 4 and Octamer-4,and negative for hematopoietic markers such as CD-14.

Spindle cell carcinoma of the mandible:a case report

Spindle cell carcinoma is a rare highly malignant squamous cell carcinoma.Here,we describe a case of a 74-yearold Chinese female who presented with a 2-week history of pain and swelling in the left retromolar region.Surgical resection and titanium plate prosthesis were performed and histological analysis revealed spindle squamous cell carcinoma.

A Pediatric Case of Tuberculous Osteomyelitis of the Mandible Mimicking a Bony Malignant Tumor

Background: Tuberculosis is a granulomatous infectious disease which is still being a real health problem in developing countries. Mainly, this specific infection affects pulmonary sites, but, the occurrence in extra-pulmonary sites is more and more reported. However, when extra-pulmonary tuberculosis affects the cervico-facial region, the cervical lymph nodes are the most involved. Aim: Throughout this case report, we put emphasis on keeping in mind of the possible tuberculous infection in a chronic lesion of mandible in children. Case presentation: In this article, we present a case of a 2-year-old child who was complaining of swelling of the right angle of the mandible. The computed tomography showed an osteolytic lesion suggesting tuberculous osteomyelitis but didn’t rule out a bony malignant neoplasm of the mandible. The histological examination of biopsy of the lesion proved the tuberculous osteomyelitis of the mandible. The child has received anti-tubercular therapy for 9 months, and she marked a good recovery. Conclusion: In children, tuberculous osteomyelitis of the mandible is a curable disease without sequel when diagnosis is given at the right time.

Intrabony Schwannoma of the Mandible: Case Report and Review of Literature

This paper focuses on the case of intrabony mandibular schwannoma in a 39 yrs healthy male who was addressed by his dentist for an asymptomatic radiolucency of the left mandibular corpus. Computed Tomography Dentascan showed a soft tumour continuous to the path of the inferior alveolar nerve. Confirmation was made after surgical excision and careful histological examination. Radiolucent images of the mandible are frequently met by dentists and oro-facial surgeons, and suggest first odontogenic cysts because of their high frequency. But even if sheath nerve tumours are very rare, this case report reminds the necessity to keep them in mind.

Radiation-induced osteosarcoma of the maxilla and mandible after radiotherapy for nasopharyngeal carcinoma

Background:The increasing incidence of radiation-induced osteosarcoma of the maxilla and mandible(RIOSM) has become a significant problem that can limit long-term survival.The purpose of this study was to analyze the association of clinicopathologic characteristics with treatment outcomes and prognostic factors of patients who developed RIOSM after undergoing radiotherapy for nasopharyngeal carcinoma(NPC).Methods:We reviewed the medical records of 53,760 NPC patients admitted to Sun Yat-sen University Cancer Center during the period August 1964 to August 2012.Of these patients,47 who developed RISOM and met inclusion criteria were included in this study.Two of these 47 patients refused treatment and were then excluded.Results:For all patients treated for NPC at Sun Yat-sen University Cancer Center during the study period,the total incidence of RIOSM after radiotherapy was 0.084%(47/53,760).Two patients(4.4%) had metastases at the diagnosis of RIOSM.Thirty-nine of the 45(86.7%) patients underwent surgery for RIOSM;most patients(24/39;61.5%) who underwent resection had gross clear margins,with 15 patients(38.5%) having either a gross or microscopic positive margin.All patients died.The 1-,2-,and 3-year overall survival(OS) rates for the entire cohort of 45 patients were 53.3%,35.6%and 13.5%,respectively.The independent prognostic factors associated with high OS rate were tumor size and treatment type.Conclusions:RISOM after radiotherapy for NPC is aggressive and often eludes early detection and timely intervention.Surgery combined with postoperative chemotherapy might be an effective treatment to improve patient survival.

Establishment of a three-dimensional finite element model for gunshot wounds to the human mandible

Objective:To investigate the feasibility of a finite element model as an ideal research tool for human maxillofacial gunshot wounds.Methods:Mandible CT scan data on the Chinese Visible Human were imported into MIMICS software to obtain the surface mesh of the mandible.Then,these surface-meshed models were imported into ANSA software for automatic net generation.Elements and nodes were partitioned on the basis of the mesh to obtain a three-dimensional finite element model for the mandible with every internal parameter consistent with those of our previously developed model in the pig mandible.The finite element model was imported into LS-DYNA for computation.Finally,the LS-POST was used to complete the simulation and the measurements.Results:A three-dimensional finite element model was successfully established for gunshot wounds in the human mandible.The stress distribution and the degree of injury were simulated dynamically for shots from two types of projectiles in the mandible at one entry angle and at three impact velocities.Conclusion:Three-dimensional finite element models will become ideal research tools for treatment of ballistic wounds of the human maxillofacial region.Using this human mandibular model as a foundation,we will be able to successfully develop three-dimensional finite element models for human maxillofacial gunshot wounds.

Fixed Bicortical Screw and Blade Implants as a Non-Standard Solution to an Edentulous (Toothless) Mandible

Aim This paper deals with the treatment of an atrophied toothless mandible with a fixing bridge carried by two nonstandard implant systems. Methodology Four bicortical screws were implanted into the frontal part of the mandible and one implant on each side was placed into the distal area of the mandible as a support for a fixing bridge. Results During the years 2002–2007 the authors placed a total of 256 bicortical screw and 84 blade implants. During this period only four bicortical screws and one blade implant failed. The primary and secondary surgical success rate was therefore above 98%, while the prosthetic success rate was 100%. （Bridges which had to be re-fabricated due to implant failure were not taken into account.） Conclusion This approach is recommended as a highly successful and affordable option for a wide range of patients.

3D kinematicmandiblemodel to designmandibular advancement devices for the treatment of obstructive sleep apnea

Mandibular advancement devices(MADs)are one of the treatments used for Obstructive sleep apnea(OSA).MADs try to maintain the mandible in an advanced position to keep the upper airways open when sleeping.To achieve this goal,most current MADs limit the mouth opening to a few millimetres.The study of the kinematic behaviour of the patient’s jaw is essential in order to design devices that allow greater aperture ranges.For this purpose,a 3D multibody model that reproduces jaw movement has been developed in this work.To this end,the movement of the lower incisor has been determined by means of a vision system and reflective markers.In addition,the kinematics of the temporomandibular joint has been modelled.Next,the device is designed and printed using a cam-follower mechanism.This way,the cam profiles and the followers are optimally designed and positioned for each patient depending on the physiognomy of the jaw and the opening and advancing movement prescribed by the specialist.