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Nevoid basal cell carcinoma syndrome (NBCCS) is an autosomal dominant disorder characterized by tumorigenesis and physical deformities. Although more than 50 clinical manifestations have been described, only two major criteria or one major and two minor criteria are necessary for diagnosis. The most frequently observed manifestation in the oral and the maxillofacial region is an odontogenic keratocyst. In this study, we describe a 14-year-old boy with a diagnosis of NBCCS who presented with a central odontogenic fibroma (COF) in the mandible. This report highlights the importance of precise diagnosis and the choice of surgical method for COF.

Objective Hemifacial microsomia (HFM) is a congenital anomaly characterized by unilateral underdevelopment of the mandible and ear. This study was conducted to characterize maxillofacial morphology and dental development in Japanese patients with HFM. Design This is a retrospective hospital-based study. Patients The subject population comprised 12 boys and 12 girls (average age, 9.3 years) diagnosed with HFM. Main Outcome Measures We used posteroanterior (PA) and lateral cephalograms obtained at the first visit to analyze maxillofacial morphology and orthopantomograms to compare dental development between the affected and unaffected sides. Dental development was graded according to Nolla's stages of tooth calcification. Results PA cephalogram analysis showed that the occlusal plane inclined upward on the affected side in each patient. The mandibular body and ramus were smaller on the affected side than on the unaffected side. Lateral cephalogram analysis showed that the patients tended to have steep mandibles, large gonial angles, and a slightly convex facial structure. The affected side/unaffected side ratio of the mandibular body and ramus correlated with SNB, ANB, convexity, and mandibular plane. The difference in dental development between the affected and unaffected sides was significant at the mandibular molars and the mandibular canine. Conclusions This study demonstrates a correlation between lateral and frontal measurement parameters in patients with HFM. The data also showed delayed calcification in the mandibular molars on the affected side.

This study attempted to identify appropriate materials for restoration of enamel defects in the primary dentition, which were classified by severity and region with the modified developmental defects of enamel index. To identify the most appropriate materials, we used restorative materials to protect teeth and evaluated clinical outcomes of restoration. Three materials were used for restoration or repair after dislodgement of restorations. Our findings in this case suggest that, because of its durability and esthetic advantages, adhesive resin is beneficial for patients with enamel defects, particularly for restorations of less than two-thirds of the extent of the defect.

Tooth induction by xenogenic graft of reconstructed human tooth germ components has never been attempted. Here we report our first attempt at a transplantation of human tooth germ components, heterologously recombined with mouse dental epithelia, into immunocompromised animals. Human third molar tooth germs enucleated from young patients as prophylactic treatment for orthodontic reasons were collected. The whole or minced human dental papilla was reconstructed with human- or mouse molar enamel epithelium, and transplanted in the dorsal aspect of C.B-17/Icr-scid Jcl mice. The transplant of human dental papilla reconstructed with human enamel epithelium formed thin dentin and immature enamel layers by 3 to 4 weeks, but remained extremely small in quantity due to a shortage of epithelial components in the graft. The addition of E16 mouse molar enamel organs (n=10-12) to each graft augmented the formation of tooth germ-like structures, but the differentiation of mouse molar ameloblasts was suppressed. However, once a solid layer of mineralized dentin was established, mouse ameloblasts accelerated their differentiation, and completed the enamel matrix formation and maturation within the following 4 weeks, whereas human ameloblasts, which had interacted with human dental papilla, remained in the stage of matrix formation during the same period. These data imply that, in reconstructed transplants, the differentiation of mouse dental epithelia is restrained by putative suppressive factors derived from human dental papilla until they are separated by mineralized dentin layers that serve as a diffusion barrier. The mouse enamel organ nevertheless retains its own phenotypic characteristics and intrinsic timing of cell differentiation and function.

Recently, the research on the stem cells is developing rapidly in the odontology. Mesenchymal stem cells (MSCs) have the possibility useful for the stem cell treatment and the tissue engineering. STRO-1 is one of the mesenchymal stem cell markers. In this study, we examined the characterization of STRO-1 positive cells derived from human wisdom tooth germs (hWTGs) compared with STRO-1 negative cells. As positive control, we used human mesenchymal stem cells (HMSC) on purchase. STRO-1 positive cells derived from hWTGs showed Alcian blue positive matrix like HMSC when cultured in chondrogenic induction medium. STRO-1 negative cells from hWTGs did not show such matrix. Nodule formation stained with Alizarin red was performed not only by STRO-1 positive cells but also STRO-1 negative cells cultured in osteogenic induction medium. It is suggested that STRO-1 positive cells derived from hWTGs are useful for the stem cell treatment and the tissue engineering.

The concentration and distribution of alpha 2HS glycoprotein in teeth from patients with heritable dentin disorders were examined utilizing immunological techniques. ELISA for the quantitative determination showed lower concentrations of alpha 2HS glycoprotein in dentins of patients with heritable disorders than in the control; some cases contained very low and others intermediate concentrations. Immunohistochemical findings indicated that the concentration of this protein was correlated to the regularity of the dentinal tubules. This result suggests that alpha 2HS glycoprotein is incorporated into dentin in concomitance with the development of the dentinal tubule, especially with the deposition of peritubular dentin. Incorporation of this protein into dentin is thought to involve the function of odontoblasts.

We examined the isolation of mesenchymal stem cells from human wisdom tooth germs (hWTGs) or human periodontal ligament (hPDL) and compared their characteristics. Collection rate of STRO-1 positive cells from WTGs was 6.01% but from PDL was 2.22%. After 7 days’ culture, alkaline phosphatase activity of stem cells derived from WTGs was increased and it was statistically higher than those of PDL stem cells. After 14 days, protein content of stem cells derived from WTGs became statistically higher than those of PDL stem cells. It is suggested that hWTGs are useful for stem cell treatment and tissue engineering.

We examined the immunohistochemical localization and isolation of mesenchymal stem cells in human wisdom tooth germs. Pericytes of blood vessels in the dental papilla and ameloblasts were stained strongly, but odontoblasts reacted weakly with STRO-1 and CD146. The STRO-1 positive cells represented approximately 7% of the total cell population. It is suggested that human wisdom tooth germs are useful for the stem cell treatment and the tissue engineering.

The presurgical nasoalveolar molding plate appliance with stent (PNAM) extended from the palatal molding plate; to correct the nostril shape of infants with cleft lip and palate is well known. The PNAM appliance is based on the finding that a high degree of plasticity is maintained in the cartilage of infants during the first 6 weeks after birth. However, on the current PNAM protocol described by Grayson et al. the nasal stent is supposed to be an adjunct to the palatal molding plate after reducing the severity of the alveolar cleft width. We have used the modified Hotz's plate from the setup model and built up the nasal stent even before reducing the severity of the alveolar deformity. In this study we assess the effects of the modified Hotz's plate and the modified PNAM appliance for the alveolar and palatal form. The lateral deviation of the incisal point, the width of the palatal cleft, and the degree of curvature of the palatal vault were first evaluated on plaster models. The PNAM group is smaller on the lateral deviation of the incisal point than the modified Hotz's group. The decreased average width of the palatal cleft and curvature of the palate, was almost the same in both the modified Hotz's and PNAM groups. In comparison with the modified Hotz's plate, the modified PNAM appliance also improves the molding of the alveolar segments and reduces cleft width.