Pathologic jaw lesions associated with impacted teeth.

The aim of this study was to evaluate the histopathologic diagnoses and radiographic characteristics of lesions associated with impacted teeth. In this retrospective study, 2624 biopsy reports were assessed. If the report was a record of a pericoronal lesion, the age and sex of the patient and the location, microscopic diagnosis, radiographic features, and size of the lesion were recorded. The Pearson chi-square, Kruskal-Wallis, and Fisher exact tests were used for statistical analysis. In total, 189 patients (7.2%) had lesions associated with impacted teeth. The mean (SD) age of affected patients was 25.91 (14.38) years, and 51.9% of patients with pericoronal lesions were male. The most common lesion sites were the posterior region of the maxilla (43.3%) and the posterior region of the mandible (38.0%). Dentigerous cysts (DCs) constituted 64.6% of the lesions, and odontogenic keratocysts (OKCs) represented 18.5%. Radiographs were available in 153 cases, and most lesions were radiolucent (96.1%), had well-defined outlines (99.3%), and were unilocular (87.6%). Lesions larger than 2.0 cm were 5.5 times more likely than smaller lesions to be diagnosed as non-DC lesions (P = 0.001; Kruskal-Wallis test). Although most of the lesions associated with impacted teeth were DCs, there were other lesions with aggressive behavior, such as OKCs, ameloblastomas, and glandular odontogenic cysts, which require more extensive treatment. Lesions that were 2.0 cm or greater showed a higher probability of being non-DC lesions.

Benign polypoid adenomyomatous endometrium associated with hpt-JT syndrome: a case report.

Hyperparathyroidism-jaw tumor (HPT-JT) is an autosomal dominant disorder responsible for benign and/or malignant tumors. Affected women often present life-threatening menorrhagia that leads to the identification of uterine tumors, and experience miscarriages and infertility. Overall though, fewer data concerning gynecological pathologies related to HPT-JT syndrome are available. We report the case of a 32-year-old woman with HPT-JT syndrome, referred for recurrent vaginal bleeding, with a history of repeated endometrial polyps and infertility. We also review the literature that explores medical options for these women.

Phosphaturic mesenchymal tumor with an admixture of epithelial and mesenchymal elements in the jaws: clinicopathological and immunohistochemical analysis of 22 cases with literature review.

Information on the heterogeneity of phosphaturic mesenchymal tumor, a rare entity associated with tumor-induced osteomalacia, is limited. In this retrospective analysis of 222 phosphaturic mesenchymal tumors, 22 cases exhibited mixed mesenchymal and epithelial elements, which we propose to term "phosphaturic mesenchymal tumor, mixed epithelial, and connective tissue type." Phosphaturic mesenchymal tumor of the mixed epithelial and connective tissue type showed a distinctive and significant male predominance (male:female = 2.67:1), with most patients diagnosed at <40 years old. Moreover, all tumors were mainly located in the alveolar bone with focal invasion into surrounding soft tissue and oral mucosa, which could be detected preoperatively by oral examination. The mesenchymal component, composed of spindled cells resembling fibroblasts or myofibroblasts arranged in a storiform or fascicular pattern, exhibited a less prominent vasculature and lower cellularity than the typical phosphaturic mesenchymal tumor (mixed connective tissue type). The epithelial component was typically haphazardly and diffusely distributed throughout the tumor, forming small, irregular nests resembling odontogenic epithelial nests. All cases were immunoreactive for fibroblast growth factor-23, somatostatin receptor 2A, and NSE in both components. Mostly also demonstrated positive staining for CD99 (21/22, 96%), CD56 (16/22, 73%), Bcl-2 (21/22, 96%), and D2-40 (19/22, 86%) in one or both components. S100 was positive in both components in one of seven cases. Interestingly, immunoreactivity was typically stronger and more diffuse in the epithelial than in the paired mesenchymal components. The mesenchymal component was also diffusely positive for CD68 (17/17, 100%) and showed variable focal staining for SMA (15/22, 68%) and CD34 (9/19, 47 %). These results indicate that phosphaturic mesenchymal tumor of the mixed epithelial and connective tissue type has distinctive clinicopathological characteristics and a polyimmunophenotypic profile.

Clinical parameter of odontoma with special emphasis on treatment of impacted teeth-a retrospective multicentre study and literature review.

OBJECTIVES: Odontoma-separated into complex (CxOD) and compound (CpOD) subtypes-represents the most frequent odontogenic malformation. Retention of permanent teeth is a common symptom. Therefore, in a series of odontomas, an analysis of the management of retained teeth was conducted. MATERIALS AND METHODS: In a retrospective multicenter study of two University Medical Centers and one private praxis in Germany, demographic and clinical data regarding odontomas from 01/2000-03/2015 were obtained. In particular, the influence of operative therapy on the dentition and on the treatment of impacted teeth was analyzed. RESULTS: Forty-five patients with 15 CxOD and 30 CpOD were included. Initial symptoms were delayed eruption of permanent teeth (n = 11), pain (n = 4), and swellings (n = 2); 28 cases were discovered by incidence, all of them via panoramic radiographs. The mandible/maxilla ratio was about 1:0.55 (29/16). Thirty-five out of 45 odontomas were in close proximity of at least one tooth (n = 16 at molars). A total of 14 teeth were extracted (CxOD: n = 5; CpOD: n = 9). Extractions had to be conducted more often in older patients (mean age 39.8 vs. 25.6 years). Of the non-extracted teeth, 8 teeth were displaced and retained. Of those, 4 teeth were aligned in the dental arch via orthodontic help and 2 teeth erupted spontaneously after operation during the follow-up period. In all cases, no relapse was seen. CONCLUSION: Odontomas can cause displacement as well as malformation and resorption of the adjacent teeth. CLINICAL RELEVANCE: Mostly, removal of odontomas is conducted. Extirpation of odontoma can allow for normal tooth eruption, often rendering extractions avoidable. Orthodontic alignment, though sometimes challenging, is a reasonable therapeutic option. These findings underline the value of the panoramic radiograph in preventive dentistry in younger patients.

Secondary jaw aneurysmal bone cyst (JABC)--a possible misnomer? A review of literature on secondary JABCs, their pathogenesis and oncogenesis.

CONTEXT: Aneurysmal bone cysts are rare pseudocysts, commonly seen in long bones and vertebral column. Although a well described and reported lesion, many misconceptions still prevail regarding their etiopathogenesis. Many of the reported cases of jaw aneurysmal bone cysts (JABC) present with another bone pathology. AIMS: The purpose of this review was to evaluate the incidence of neoplastic lesions occurring simultaneously with a JABC (in contrast to primary JABCs). Any pathogenetic and oncogenetic association between primary and secondary jaw ABCs has been reviewed and discussed. SETTINGS AND DESIGN: A methodical narrative review of literature was performed, given the incidence of mostly case reports on this topic. METHODS AND MATERIAL: A methodical electronic search of Pubmed, Pubmed Central, Medline and Cochrane databases was performed for reported cases of JABC. These articles were analysed and segregated into primary and secondary ABC and, if secondary, the lesion it concurrently occurred with. Another search was conducted to yield articles discussing the cytopathogenetic and oncogenetic origins of ABCs. RESULTS AND CONCLUSIONS: About 15% of the ABCs reported were of secondary nature. Amongst the associated lesions, cement-ossifying fibroma and ossifying fibroma were the most common, followed by fibrous dysplasia and central giant cell granuloma. No ABCs were associated with metastatic changes. The search for histopathogenesis pointed to a specific cytogenetic abnormality as the origin of primary ABCs, with USP6 as its main oncogene and spindle cell as the neoplastic cell, unlike with secondary ABCs, suggesting that they are distinct pathological processes.

Assessment of quality of life in giant ameloblastoma adolescent patients who have had mandible defects reconstructed with a free fibula flap.

BACKGROUND: The reconstruction of mandibular defects after giant ameloblastoma resection is one of the most challenging problems facing reconstructive surgeons. Mandibular resection has been associated with a poor quality of life (QOL), particularly in adolescent patients reconstructed with a free fibula flap. This study aims to evaluate QOL outcomes in adolescent patients who have had mandibular resections of giant ameloblastoma and reconstruction with a free fibula flap and to collect information about their socio-cultural situation. METHODS: The present study assessed 45 adolescent patients who had undergone immediate mandible reconstruction with a free fibula flap for faint ameloblastoma using University of Washington Quality of Life (UW-QOL) and 14-item Oral Health Impact Profile (OHIP-14) questionnaires. RESULTS: Thirty-five of the 54 questionnaires were returned (64.81%). In the UW-QOL, of the twelve disease-specific domains, the best three scores from the patients related to pain, shoulder and appearance and the worst three scores related to chewing, anxiety and saliva. In the OHIP-14, the lowest-scoring domain was handicap, followed by physical pain and social disability. CONCLUSIONS: Mandibular reconstruction with a free fibular flap significantly influenced the adolescent patients' QOL. Adolescent patients pay more attention to postoperative facial appearance; this should be considered in surgical planning.

A family case report of parathyroid carcinoma associated with CDC73 mutation in hyperparathyroidism-jaw tumor syndrome.

Background: Hereditary primary hyperparathyroidism (PHPT) accounts for 5-10% of all PHPT cases, necessitating genetic testing for diagnosis and management. Among these, hyperparathyroidism-jaw tumor syndrome (HPT-JT) is an autosomal dominant disorder caused by CDC73 mutations with variable clinical presentations and incomplete symptoms. Case summary: The proband, diagnosed with PHPT, underwent parathyroidectomy at the age of 41 with pathological examination of parathyroid carcinoma (PC). Hereditary PHPT was initially suspected due to the early-onset PHPT and family history. Genetic testing identified a heterozygous CDC73 mutation, NM_024529.4: c. 687_688delAG (p. Arg229Serfs*37). Even in the absence of jaw tumors, the diagnosis of HPT-JT was confirmed based on the discovery of renal cysts. A secondary thyroidectomy was performed to reduce the risk of recurrence. Conclusion: Genetic testing is strongly recommended in cases of early-onset PHPT, family history, jaw tumors, renal and uterine involvement, atypical parathyroid tumors, and PC. This testing provides valuable information for personalized management, and counseling is available for affected families.

Evaluation of selected speech parameters after prosthesis supply in patients with maxillary or mandibular defects.

BACKGROUND: Ablative surgery of oropharyngeal tumors frequently leads to defects in the speech organs, resulting in impairment of speech up to the point of unintelligibility. The aim of the present study was the assessment of selected parameters of speech with and without resection prostheses. PATIENTS AND METHODS: The speech sounds of 22 patients suffering from maxillary and mandibular defects were recorded using a digital audio tape (DAT) recorder with and without resection prostheses. Evaluation of the resonance and the production of the sounds /s/, /sch/, and /ch/ was performed by 2 experienced speech therapists. Additionally, the patients completed a non-standardized questionnaire containing a linguistic self-assessment. RESULTS: After prosthesis supply, the number of patients with rhinophonia aperta decreased from 7 to 2 while the number of patients with intelligible speech increased from 2 to 20. Correct production of the sounds /s/, /sch/, and /ch/ increased from 2 to 13 patients. A significant improvement of the evaluated parameters could be observed only in patients with maxillary defects. The linguistic self-assessment showed a higher satisfaction in patients with maxillary defects. CONCLUSION: In patients with maxillary defects due to ablative tumor surgery, an increase in speech performance and intelligibility is possible by supplying resection prostheses.

Metastatic cancer identified in osteonecrosis specimens of the jaws in patients receiving intravenous bisphosphonate medications.

PURPOSE: The aim of the present study was to investigate the microscopic presence of metastatic cancer in jaw specimens clinically and histologically diagnosed as having osteonecrosis in patients receiving intravenous bisphosphonate medications. PATIENTS AND METHODS: A retrospective cohort multicenter study was designed. Patients from the University of Tennessee Medical Center, New York University Medical Center, and New York Center for Orthognathic and Maxillofacial Surgery were enrolled who had been treated with intravenous bisphosphonate medications for an underlying diagnosis of cancer and who had been clinically diagnosed with bisphosphonate-related osteonecrosis of the jaws (BRONJ). The institutional review boards approved the present study. The primary predictor variable was the clinical presence of BRONJ. The primary outcome variable was the microscopic presence of metastatic cancer in the osteonecrotic jaw specimens. RESULTS: A total of 744 sites of BRONJ were clinically diagnosed. Of these sites, 552 (74%) were diagnosed in patients who had received intravenous bisphosphonate medications. Of these 552 sites, 357 (65%) underwent microscopic evaluation through biopsy, sequestrectomy, or resection with curative intent. Of the 357 sites of BRONJ subjected to microscopic analysis, 19 (5.3%) sites were diagnosed with 20 cancers in 16 patients. CONCLUSIONS: Albeit rare, the presence of cancer in a BRONJ specimen represents 1 explanation for the development of osteonecrosis in patients exposed to intravenous bisphosphonate medications in whom a clinical diagnosis of BRONJ has been applied. Additional molecular information is needed to provide an explanation for this observation.

Phenotypic Profiling and Molecular Mechanisms in Hyperparathyroidism-jaw Tumor Syndrome.

CONTEXT: Hyperparathyroidism-jaw tumor (HPT-JT) syndrome is a heritable form of primary hyperparathyroidism caused by germline inactivating mutations in CDC73 encoding parafibromin and is associated with an increased risk of parathyroid cancer. There is little evidence to guide the management of patients with the disease. OBJECTIVE: (1) Characterize the natural history of HPT-JT, (2) correlate genotype and histology of parathyroid tumors with parafibromin immunostaining, (3) understand molecular changes downstream to CDC73 loss. DESIGN: Retrospective study of patients with HPT-JT syndrome (genetically confirmed or affected first-degree relatives). Independent review of uterine tumor from 2 patients and staining for parafibromin on parathyroid tumors from 19 patients (13 adenomas, 6 carcinomas) was performed. RNA-sequencing was performed in 21 parathyroid samples (8 HPT-JT-related adenomas, 6 HPT-JT-related carcinomas, and 7 sporadic carcinomas with wild-type CDC73). RESULTS: We identified 68 patients from 29 kindreds with HPT-JT with median age at last follow-up of 39 [interquartile range, 29-53] years. A total of 55/68 (81%) developed primary hyperparathyroidism; 17/55 (31%) had parathyroid carcinoma. Twelve of 32 (38%) females developed uterine tumors. Of the 11 patients who had surgical resection for uterine tumors, 12/24 (50%) tumors were rare mixed epithelial mesenchymal polypoid lesions. Four of 68 patients (6%) developed solid kidney tumors; 3/4 had a CDC73 variant at p.M1 residue. Parafibromin staining of parathyroid tumors did not correlate with tumor histology or genotype. RNA-sequencing showed a significant association of HPT-JT-related parathyroid tumors with transmembrane receptor protein tyrosine kinase signaling pathway, mesodermal commitment pathway, and cell-cell adhesion. CONCLUSIONS: Multiple, recurrent atypical adenomyomatous uterine polyps appear to be enriched in women with HPT-JT and appear characteristic of the disease. Patients with CDC73 variants at p.M1 residue appear predisposed to kidney tumors. CLINICAL TRIAL NUMBER: NCT04969926.

Oral and maxillofacial considerations in Gardner's Syndrome.

Gardner's Syndrome is a variant of familial adenomatosis polyposis (FAP) with a triad consisting of polyps of the colon, multiple osteomas and surface tumors of soft and hard tissue. The intestinal polyps have a %100 risk of undergoing malignant transformation, therefore early identification of this disease is very important. There are several symptoms of Gardner's syndrome in the oral and maxillofacial surgery, which can be discovered during routine dental examination. We report a case of a 25-year old male patient with Gardner's syndrome who has not any intestinal polyps but osteomas in the mandible and jaw deformalities.

Association Between Parafibromin Expression and Presence of Brown Tumors and Jaw Tumors in Patients with Primary Hyperparathyroidism: Series of Cases with Review of the Literature.

BACKGROUND Brown and jaw tumors are rare entities of poorly understood etiology that are regarded as end-stage of bone remodeling in patients with long-lasting and chronic hyperparathyroidism. Jaw tumors are mainly diagnosed in jaw tumors syndrome (HPT-JT syndrome) and are caused by mutation in the CDC73 gene, encoding parafibromin, a tumor suppressing protein. The aim of this work is to present 4 cases of patients in whom the genetic mutation of the CDC73 gene and clinical presentation coexist in an unusual setting that has not yet been described. CASE REPORT We present cases of 4 patients with primary hyperparathyroidism. Three were diagnosed with brown tumors (located in long bones, ribs, iliac, shoulders) and 1 with brown and jaw tumors. Expression of parafibromin in affected parathyroid tissues were analyzed. In patients without positive parafibromin staining, we searched for CDC73 mutation using next-generation sequencing. Parafibromin staining was positive in 1 patient with brown tumors and was negative in 2 individuals with brown tumors and 1 with brown and jaw tumors. CDC73 mutation was detected in two-thirds of patients (60%) with negative staining for parafibromin and brown tumors. MEN1 mutation was found in the patient with brown tumor and positive staining for parafibromin. CONCLUSIONS Patients with hyperparathyroidism and coexistence of brown tumors or jaw tumors might have decreased expression of parafibromin in parathyroid adenoma tissue, which might be caused by CDC73 mutation and suggest a genetic predisposition. Further research on much larger study groups is needed.

Calcifying odontogenic cysts associated with odontomas: confocal laser scanning microscopy analysis of 13 cases.

The so-called calcifying odontogenic cyst (COC) represents a heterogeneous group of lesions that exhibit a variety of clinico-pathologic features. It is an uncommon lesion and represents less than 2% of all odontogenic cysts and tumors. Recently, these lesions have been reclassified as calcifying cystic odontogenic tumors (CCOT), according to the new World Health Organization (WHO) classification. CCOT are frequently found in association with, or containing areas histologically identical to, various types of odontogenic tumors, such as complex/compound odontomas. This work analyzed clinical and histological data deriving from 13 patients affected by CCOT associated with odontomas. Moreover, a confocal laser scanning microscope (CLSM) analysis was undertaken to further a better understanding of the nature of this peculiar lesion.

Osseous (cemento-osseous) dysplasia of the jaws: clinical and radiographic analysis.

OBJECTIVES: To explore the demographic characteristics and clinical features among patients with osseous (cemento-osseous) dysplasia (OD/COD) of the jaws and to determine the frequency of particular radiographic characteristics. METHODS: The charts and radiographic reports of 118 patients with OD/COD, obtained from the archives of the University of Toronto discipline of oral and maxillofacial radiology, were reviewed. Demographic and clinical data, radiographic findings and final diagnoses were collected and analyzed to determine typical characteristics. RESULTS: Of the 117 patients for whom age and sex were known, the majority (97 [82.9%]) were female; these female patients had a mean age (± standard deviation) of 44.3 ± 13.4 years. Eighty-three (72.2%) of the 115 patients for whom symptoms were known were clinically asymptomatic. Ninety-three patients (78.8%) had OD/COD at single sites (i.e., periapical OD/COD), and 25 (21.2%) had OD/COD at multiple sites (i.e., florid OD/COD). In addition, 15 (12.7%) of the cases were associated with one or more simple bone cysts, and 13 (11.0%) were associated with osteomyelitis. In most cases, the OD/COD was unilateral, with the lesion being located in the mandible, usually associated only with the posterior teeth. The lesions exhibited well-defined, sclerotic or corticated margins (108 patients [91.5%]) and were surrounded by a radiolucent border. Minimal effects on surrounding structures were observed. As well, 85 (72.0%) of the lesions were in the mixed radiolucent-radiopaque stage, with dense, cementum-like radiopacities. CONCLUSIONS: The majority of cases of OD/COD occurred in women in the fifth decade of life, and most cases were asymptomatic. OD/COD was more likely to present as solitary lesions but also occurred in association with simple bone cysts or osteomyelitis.

Retrospective study of 25 cases of keratocystic odontogenic tumor: epidemiology and treatment.

AIM: Keratocystic odontogenic tumor (KOT) is a benign odontogenic neoplasm with locally aggressive behavior and high recurrence rates. It is associated with nevoid basal cell carcinoma syndrome which usually has a more rapid growth. The aim of the study is to report the experience of our service on diagnosis and treatment of KOT. MATERIALS AND METHODS: Twenty-five cases of KOT were diagnosed between the years of 1989 and 2006. Demographic data was collected as well as diagnose and treatment. RESULTS: Fifty-six percent were female with a mean age of 33 years old. Seventy percent occurred in mandibula and all received surgical treatment, associate or not with adjuvant therapy, such as cryotherapy and Carnoy's solution. Recidive was observed in 48% of cases with a mean period of time of 18 months. CONCLUSION: Our data analysis showed the importance of previous diagnosis before enucleation procedure and long-term follow-up for recurrence early detection. Recurrence incidence is more frequent on first year after diagnosis. CLINICAL SIGNIFICANCE: KOT is a benign tumor with local aggressive behavior and therefore its treatment must consider the high index of recidive. Reports of protocol treatment should raise new discussion to decrease recurrence rates.

Ameloblastic fibro-odontoma: a clinicopathologic study of 12 cases.

OBJECTIVE: The ameloblastic fibro-odontoma (AFO) is an uncommon odontogenic tumor occurring in childhood with limited reported data on recurrence. The purpose of this AFO study was to review its clinicopathologic features, investigate treatment modalities and establish a recurrence rate. STUDY DESIGN: The clinicopathologic features of 12 new cases of AFO were analyzed and compared with those of 208 cases from the literature, with special emphasis on the clinical behavior, treatment, and recurrence rate. RESULTS: The average age was 9.4 (+/- 6.7) years with a male-to-female ratio of 1.6:1. The mandible was the site of occurrence in 59.5%. The tumor most often presented radiographically as a unilocular mixed density lesion associated with the crown of an impacted tooth. Displacement of teeth, delayed eruption and bony expansion were commonplace. There were 5 recurrences among 68 cases with adequate follow-up for a recurrence rate of 7.4%. All recurrences were attributed to incomplete removal at the time of the initial surgery. CONCLUSIONS: The AFO is a childhood tumor most often affecting the posterior jaws and frequently causing bony expansion with profound affects on the dentition. Conservative surgical removal with extraction of the associated teeth is recommended. The established recurrence rate is less than 10%.

Oro-facial manifestations of Burkitt's lymphoma: an analysis of 680 cases from Malawi.

Burkitt's lymphoma (BL) is a highly aggressive, fast growing, mature B-cell non-Hodgkin's Lymphoma (NHL) and has one of the highest proliferation rates of any human tumour. There are three forms of BL: endemic or the African form (eBL), sporadic or non-endemic form (sBL) and the immunodeficiency-associated form in HIV-AIDS. The survival rate of a child with BL is dependent upon rapid diagnosis and treatment. The aim of the present study was to determine the oro-facial manifestations in children with BL in Malawi. It was carried out in two parts: the first, a retrospective record-based study (2005-2007) consisting of 661 cases of BL and the second, a prospective study (June 2008 -October 2009) documenting 19 cases of suspected and confirmed cases of BL. In the retrospective study, two thirds presented with BL at various sites of which the abdomen was the most common site. The 5-9 year age group predominated with an average peak incidence of 7 years and accounted for 60.0% of all the cases. There was a male preponderance with a ratio of male to female of 1.6:1. The maxilla was the most common site for oro-facial BL (13.7%) followed by the mandible (7.2%), cheeks (5.7%), maxilla and mandible (4.5%) and cervical lymph nodes (4.1%). Of the 397 with BL, 41.4% were tested for HIV and 37.97% were HIV-negative while 5% were HIV-positive. In the prospective study, females predominated with a male to female ratio of 1.1:1 and the mandible was the most common site accounting for 19.04%. The age group 5-9 years predominated with 68.4% relative frequency. Generally the trend of BL had decreased from 2005 to 2007 possibly due to better access to health services, increased use of bed-treated mosquito nets for malaria prevention and knowledgeable healthcare workers. All oral healthcare and other healthcare workers need to be educated on the oro-facial manifestations of BL for prompt referral and management. This would result in a better prognosis since BL is curable as it responds favourably to chemotherapy. Furthermore, communities need to be educated on the early signs and symptoms of BL and the importance of visiting a hospital as soon as possible.

Bioengineering the ameloblastoma tumour to study its effect on bone nodule formation.

Ameloblastoma is a benign, epithelial cancer of the jawbone, which causes bone resorption and disfigurement to patients affected. The interaction of ameloblastoma with its tumour stroma drives invasion and progression. We used stiff collagen matrices to engineer active bone forming stroma, to probe the interaction of ameloblastoma with its native tumour bone microenvironment. This bone-stroma was assessed by nano-CT, transmission electron microscopy (TEM), Raman spectroscopy and gene analysis. Furthermore, we investigated gene correlation between bone forming 3D bone stroma and ameloblastoma introduced 3D bone stroma. Ameloblastoma cells increased expression of MMP-2 and -9 and RANK temporally in 3D compared to 2D. Our 3D biomimetic model formed bone nodules of an average surface area of 0.1 mm2 and average height of 92.37 [Formula: see text] 7.96 µm over 21 days. We demonstrate a woven bone phenotype with distinct mineral and matrix components and increased expression of bone formation genes in our engineered bone. Introducing ameloblastoma to the bone stroma, completely inhibited bone formation, in a spatially specific manner. Multivariate gene analysis showed that ameloblastoma cells downregulate bone formation genes such as RUNX2. Through the development of a comprehensive bone stroma, we show that an ameloblastoma tumour mass prevents osteoblasts from forming new bone nodules and severely restricted the growth of existing bone nodules. We have identified potential pathways for this inhibition. More critically, we present novel findings on the interaction of stromal osteoblasts with ameloblastoma.

Analysis of aberrantly spliced HRPT2 transcripts and the resulting proteins in HPT-JT syndrome.

The risk for parathyroid carcinoma is high in those with the HPT-JT syndrome. Parafibromin is a protein derived from HRPT2 gene and its inactivation has been coupled to familial form of parathyroid malignancy. We previously identified altered transcripts resulting from splice site mutation of the HRPT2 gene in a family with this syndrome. In the present work, we investigated the stability of the altered HRPT2 transcripts and translation products produced in the HPT-JT syndrome. We quantified the differentially expressed HRPT2 mRNAs using real-time RT-PCR and developed a novel monoclonal parafibromin antibody to study the expression of parafibromin in the HPT-JT syndrome. The relative quantification ratios of the wild type HRPT2 mRNA, 23 bp deleted HRPT2 mRNA, and 70 bp deleted HRPT2 mRNA in the HPT-JT syndrome were 0.68, 0.17 and 0.15, respectively. But endogenous parafibromin expression was not detectable in the HPT-JT syndrome carcinoma. The altered HRPT2 mRNAs resulting from the splice site mutation in the HPT-JT syndrome were stable, but their parafibromin translation products from the HPT-JT syndrome carcinoma were probably degraded rapidly. Additional studies that aim to fully characterize the consequences of altered HRPT2 mRNAs in HPT-JT syndrome are required to explore these possibilities.

Aneurysmal bone cysts of the jaws: analysis of 17 cases.

PURPOSE: Aneurysmal bone cysts (ABCs) are benign osteolytic lesions that occur relatively rarely in the jaws. The aim of the present study was to investigate the clinical and radiographic characteristics, pathologic features, and treatment results of ABCs of the jaws (JABCs). MATERIALS AND METHODS: A retrospective analysis of a 20-year database, including 17 cases of JABC, was performed. RESULTS: A total of 17 patients, 9 males and 8 females, aged 7 to 47 years (mean 20.4, median 14), were included. Of the 17 lesions, 15 (88.2%) were located in the mandible and 2 (11.8%) in the maxilla. A painless (12 of 17, 70.6%) or painful (3 of 17, 17.6%) swelling was the most common clinical finding. The pathologic analyses revealed that 13 JABCs (76.5%) were secondary in nature, including 11 cases associated with ossifying fibroma. Radiologically, the lesions frequently presented as multilocular (58.8%), well-defined (70.6%) radiolucencies (82.4%). Two lesions (11.8%) recurred. CONCLUSIONS: Our results suggest that most JABCs are secondary in nature and frequently associated with ossifying fibroma. The patients with JABCs presented with various clinical and radiographic features and therefore often posed a diagnostic dilemma. Resection is the preferred treatment of JABCs.