Crazing level after pin insertion in anterior primary teeth: a preliminary in vitro study

Objectives: this study aimed to investigate dentinal crack rate following parapulpal pin insertion in anterior primary teeth

Methods: thirteen sound freshly extracted primary canine teeth were horizontally sectioned 1 mm above the cementoenamel junction [CEJ]. All samples were thoroughly inspected to ensure that the teeth had no cracks. The teeth were then mounted in acrylic blocks, and subjected to drilling and insertion of a single parapulpal pin in the prepared hole. The teeth were then sectioned perpendicular to the already prepared surface at 1, 2 and 3 mm depths for further evaluation under a stereomicroscope [×12 and ×25 magnifications]

Results: no crack or crazing was observed in teeth in the control group while one out of 11 teeth in the case group had a crack

Conclusion: the use of 0.53 mm diameter self-threading pin did not increase the risk of crack formation in dentin of anterior primary teeth prior to composite restoration

Coincidence of compound odontoma and cemento ossifying fibroma; a rare case report

Objective: cemento-ossifying fibroma defines as a relative rare osteogenic neoplasm of the jaw. This tumor includes fibrous and osseous components. Odontoma is the most common odontogenic tumor containing enamel ,dentin ,cementum and pulp tissue. in this paper we report a rare case of ossifying fibroma associated with compound odontoma in the mandible

Case: A 37-years-old woman was referred to Oral Medicine department, Shahid Beheshti Dental School with complaint of swelling in the anterior part of the mandible, over 6 years period. Clinical examination revealed mandibular enlargement in right -anterior region with labial and lingual expansion and canine missing . panoramic view showed a large mixed radiolucent - radiopaque lesion associated with impacted canine.The differential diagnosis include calcifying odontogenic cyst [COC] and cemento-ossifying fibroma[COF]. Histopathologic examination established diagnosis of COF with multiple compound odontoma

Conclusion: the relationship between the occurrence of these two lesions is not clear and more studies are needed to establish the relationship between them

Ortho keratinized odontogenic cyst of mandible: a rare case report

Objective: The Ortho keratinized Odontogenic Cyst [OOC] is a rare lesion originates from dental lamina and clinically, it may be mistaken for many other odontogenic cysts and Tumors. Microscopically, It should be distinguished from KCOT because of differences in biologic behavior and histologic features

Case: An interesting case of OOC arising in the edentulous mandibular right first premolar region of a 55-year-old woman is reported. Under the initial clinical diagnosis of a residual cyst, the excisional biopsy was performed. Because of detection of an orthokeratinized epithelium lining, a definite diagnosis of OOC was made

Conclusion: Microscopic examination is crucial for making the correct diagnosis of such lesions, therefore establishing patients' prognosis accurately

Granulocytic sarcoma [chloroma] presenting as multiple sites in oral cavity: report of a case

Granulocytic sarcoma [GS] is an unusual extramedullary tumor, is composed of immature granulocytic precursor cells. The intraoral occurrence of this tumor is extremely rare. Here we report a case of GS with palatal swelling, gingival lesions in maxilla and mandible and aleukemic presentation in a 45 years old male

Expression of odontogenic genes in human bone marrow mesenchymal stem cells

Tooth loss is a common problem and since current tooth replacement methods cannot counter balance with biological tooth structures, regenerating natural tooth structures has become an ideal goal. A challenging problem in tooth regeneration is to find a proper clinically feasible cell to seed. This study was designed to investigate the odontogenic potential of human bone marrow mesenchymal stem cells [HBMSCs] for seeding in tooth regeneration. In this experimental study, three pregnant Sprague Dawley [SD] rats were used at the eleventh embryonic day and rat fetuses were removed surgically using semilunar flap under general anesthesia. The primary mandible was cut using a stereomicroscope. The epithelial and mesenchymal components were separated and the dissected oral epithelium was cultured for 3 days. We used flow cytometry analysis to confirm presence of mesenchymal stem cells and not hematopoietic cells and to demonstrate the presence of oral epithelium. Bone marrow mesenchymal stem cells [BMSCs] and cultured oral epithelium were then co-cultured for 14 days. BMSCs cultured alone were used as controls. Expression of two odontogenic genes Pax9 and DMP1 was assessed using quantitative reverse transcription- polymerase chain reaction [RT-PCR]. Expression of two odontogenic genes, Pax9 and DMP1, were detected in BMSCs co-cultured with oral epithelium but not in the control group. Expression of Pax9 and DMP1 by human BMSCs in the proximity of odontogenic epithelium indicates odontogenic potential of these cells

[Rhino-orbito cerebral mucormycosis in an otherwise healthy patient with no history of systemic disease: a case report and review of literature]

Rhino-orbito-cerebral mucormycosis is a rare invasive fungal disease, which often has a fulminant and characteristic clinical course. The patients are usually immune-compromised, with diabetic ketoacidosis. The underlying disease is an important factor determining the prognosis of infection and response to treatment. The authors report a case of fulminant rhino-orbito-cerebral mucormycosis with no apparent underlying disease. Therapy included surgical intervention and systemic administration of amphotericin B. However, due to the aggressive behavior of disease and occult underlying systemic condition the treatment was unsuccessful and the patient died after debridement and medical therapy. Only a few cases of Rhino-orbito-cerebral Mucormycosis have been reported in the literature with no identified predisposing factor. In our case, no specific predisposing factors were found accompanying the fulminant progression of rhino-orbito-cerebral mucomycosis

[Histological evaluation of regeneration in rabbit calvarial bone defects using demineralized bone matrix, mesenchymal stem cells and platelet rich in growth factors]

Regeneration of large bone defects is a major challenge in maxillofacial reconstruction. The present study evaluated the efficacy of simultaneous use of demineralized bone matrix [DBM], mesenchymal stem cells [MSCs] and platelet rich in growth factors [PRGF]. Stem cells were isolated from the femoral bone marrow of rabbits and their stem cell nature was confirmed. PRGF was prepared by drawing 5 cc of blood from the heart of rabbits and its centrifugation. A total of four 8mm defects were surgically created in rabbits calvaria using a trephine bur. Third passage cells were loaded on DBM and stored in an incubator for 24 hours. DBM, DBM+PRGF, DBM+MSCs and DBM+PRGF+MSCs were used in groups 1, 2, 3, and 4, respectively. At 6 and 12 weeks rabbits were sacrificed using vital perfusion. Histomorphometric analysis was performed on 5 micro m sections stained with Hematoxylin and Eosin [H and E]. Data were analyzed using SPSS version 14 software and ANOVA test. Histomorphometric analysis of the sections at 6 and 12 weeks post-operation demonstrated 74.6% and 20.31% osteogenesis in group 1, 14.35% and 28.44% in group 2, 17.75% and 31.33% in group 3 and 18.94% and 37.21% in group 4, respectively. Percentage of new bone formation was higher in group 4. However, this difference was not statistically significant [P>0.05]. It seems that simultaneous use of DBM, PRGF and MSCs results in increased bone regeneration in 8 mm rabbit calvarial bone defects when compared to the application of MSCs or PRGF alone