A Comparative Study of Oral Health Status between International and Japanese University Student Patients in Japan.

Background: The number of international students enrolled in universities in Japan is increasing. To provide better oral care services for international students, we have to understand their oral environment and dental health behaviors. However, few studies have investigated the oral health status of international university students. The object of the present study was to clarify the current oral status of international university students. Methods: The subjects were students who visited the dental department at the University of Tokyo's Health Services Center between April 2012 and March 2013. Our medical records were reviewed with regard to the following items: attributes (nationality, gender, and age); chief complaint (reason for visit); history of dental treatment; mean number of decayed (D), missing (M) or filled (F) teeth as a single (DMFT) index; degree of calculus deposition; gingival condition; and oral hygiene status. Results: The records of 554 university students (138 international and 416 non-international students) were analyzed; 88.4% of the 138 international students were from Asian countries (n = 122), of which 47.1% were from China and 10.9% from Korea, followed by North America (5.8%), Europe (4.3%), and Africa (1.5%). Although no significant differences were found regarding the history of dental treatment between international and non-international students (49.3% and 48.8%, respectively), international students had a significantly higher dental caries morbidity rate (60.1%) than non-international students (49.0%). The international students showed a significantly higher DMFT value compared with the non-international students: 5.0 and 4.0 per individual, respectively. Severe calculus deposition was observed in international students compared with non-international students (51.9% and 31.7%, respectively). Conclusions: The international university students had poorer oral health status than the non-international students, even though the result might include many uncertainties and possible biases.

A 2-Stage Reconstruction of the Jaw Using Vascularized Bone and Secondary Alveolar Ridge Augmentation With Particulate Cancellous Bone and Marrow.

PURPOSE: To present the novel technique for reconstruction of the jaw, that facilitates occlusal restoration using dental implants, in cases with wide bony defects from tumor resection. MATERIALS AND METHODS: After alveolar ridge is augmented using titanium mesh tray and particulate cancellous bone and marrow (PCBM) from iliac bone on reconstructed bone, by way of improvement of maxillomandibular relationship for dental implants. RESULTS: This 2-stage surgery underwent successfully in 3 cases. After 2-stage surgery and occlusal reconstruction using dental implant, the patients experienced no complications, and received satisfaction with results functionally and aesthetically. CONCLUSIONS: Our results suggest that, in cases where bone defect is over a wide area, in addition to vascularized bone grafts, secondary alveolar ridge augmentation using a titanium mesh tray and PCBM on grafted bone can provide satisfactory occlusion further to improvement of facial form.

A Case of Odontogenic Infection by Streptococcus constellatus Leading to Systemic Infection in a Cogan's Syndrome Patient.

Odontogenic infection in immunocompromised patients tends to extend systemically beyond the oral cavity. Our case report presents a patient with sepsis due to a Streptococcus constellatus (S. constellatus) odontogenic infection in a 64-year-old-immunocompromised woman with Cogan's syndrome. She had been suffering from chronic mandibular osteomyelitis which was thought to have been caused by dental caries and/or chronic periodontitis with furcation involvement of the left mandibular first molar. We suspect that the acute symptoms of the chronic osteomyelitis due to S. constellatus led to the systemic infection. This infection could be accelerated by the use of a corticosteroid and an alendronate. This is the first report which represents the potential association between odontogenic infection and Cogan's syndrome.

Correction of upturned nasal tip with a costal cartilage graft in bilateral cleft lip patients.

We used a piece of costal cartilage as a cartilaginous strut to correct the upturned nasal tip in patients with bilateral cleft lip. The grafted cartilage provides more definition of the tip and improves the obtuse nasolabial angle. Neither the septal cartilage nor the ear cartilage has enough strength to shape the tip. This method of correction has consistently produced favorable, long-lasting results in adults and has improved the contour of the nasal tip in younger patients.

Maxillary protraction in patients with cleft lip and palate in mixed dentition: cephalometric evaluation after completion of growth.

Objective : To clarify the short- and long-term effects of maxillary protraction (MP) in mixed dentition in patients with unilateral cleft lip and palate (UCLP). Design : Retrospective study. Setting : University of Tokyo Hospital. Patients and Intervention : Eleven Japanese patients with UCLP in mixed dentition were treated with MP and followed up until the completion of growth. Multibracket treatment had been performed after MP treatment in all patients. Main Outcome Measure : Lateral cephalograms taken before and after MP and after completion of growth were used. Posterior and anterior vertical reference lines (PV, AV) were used to measure the horizontal movements of point A, pogonion, and maxillary first molar (U6). SNA, SNB, ANB, maxillary and mandibular length, mandibular plane angle, Wits value, upper incisor inclination, overjet, and overbite were also measured. Results : Large variation was found in the effects of MP, and five patients eventually required orthognathic surgery. In average change with MP, the maxilla showed favorable forward growth. Point A had moved forward from PV but not AV. The mandible rotated backward. However, ANB and the Wits value did not improve. U6 moved forward, and the overjet improved. After MP, the skeletal Class III relationship became severe. Conclusions : MP was effective as an early treatment for UCLP patients. However, its effects showed large variation and were in conflict with facial growth. Conscientious explanation of the expected effects and associated problems should be given to the patients/parents before its application.

Submucous cleft palate: variations in bony defects of the hard palate.

We have analysed bony defects of the hard palate in patients with submucous cleft palate to find out whether velopharyngeal insufficiency (VPI) is dependent on the extent of these defects. We evaluated the maxillofacial structures associated with cleft palate by 3-dimensional computed tomography (CT) in 23 children diagnosed with submucous cleft palate. Bony defects of the hard palate were divided into Type I, defined as absent posterior nasal spine (n=12), Type II, V-shaped bony notch (moderate, n=7), and Type III, as bony defect extending into the incisive foramen (severe, n=4) defects, respectively. VPI was found in 10, 3, and 4 patients, respectively. Neither VPI nor the degree of bifid uvula was significantly associated with the types of bony defects.

Evaluation of mandibular hypoplasia in patients with hemifacial microsomia: a comparison between panoramic radiography and three-dimensional computed tomography.

OBJECTIVE: To compare the accuracy of three-dimensional computed tomography (3D-CT) and panoramic radiography in the evaluation of mandibular hypoplasia in patients with hemifacial microsomia (HFM). DESIGN: Retrospective study of imaging data. Setting : Images selected from the archives of the University of Tokyo Hospital. SUBJECTS: Twenty patients with unilateral HFM who had undergone both panoramic radiography and 3D-CT in the same period. METHOD: Mandibular deformities were classified according to the Pruzansky classification; eight patients had Grade I deformity and 12 patients had Grade II deformity. Ramus heights were measured on both panoramic radiographs and 3D-CT. MAIN OUTCOME MEASURES: Magnification in panoramic radiographs and extent of mandibular asymmetry as estimated by the affected/unaffected side ratio based on two methods were examined. The Pearson product-moment correlation coefficient was used to estimate correlations between parameters. RESULTS: The magnification of ramus heights on panoramic radiographs showed large variations in Grade II patients. The affected/unaffected side ratio estimated by the two methods showed a strong correlation in Grade I patients (correlation coefficient 0.99; p < .0001). Conversely, a weak correlation was seen in Grade II patients (correlation coefficient 0.77; p  =  .0036), and affected/unaffected side ratios from panoramic radiographs were both over- and underestimated. CONCLUSIONS: The accuracy of evaluation using panoramic radiography was fairly reliable in Grade I patients. Conversely, accuracy was poor in Grade II patients, and evaluation using 3D-CT seems preferable. The combination of two methods with careful consideration is recommended for clinical applications.

Facial morphology and occlusion of a patient with fibrodysplasia ossificans progressiva (FOP): a case report.

Fibrodysplasia ossificans progressiva (FOP) is a rare disease characterized by postnatal heterotopic ossification (HO). When HO affects the masticatory muscles, mouth opening becomes restricted. This paper presents the changes in facial morphology and occlusion of a patient with FOP who was followed from the age of 8 to age 21. At the initial examination, he had a severely protruded maxilla and Angle Class II Division 1 malocclusion. His mouth opening was restricted (5.0 mm). He had a large overjet and this enabled him to clean his teeth and to eat. Orthodontic correction was not planned, and his facial growth was closely followed with attention to his oral hygiene. The maxillary protrusion and a low mandibular plane angle became more prominent as the patient aged. His mandible rotated in a counterclockwise direction. His molars had delayed eruption or were impacted and seven were extracted. His mouth opening increased slightly and his oral hygiene improved to excellent.

Treatment of ankylosed maxillary central incisors by single-tooth dento-osseous osteotomy and alveolar bone distraction.

When tooth ankylosis occurs in growing children, the ankylosed tooth fails to erupt and gradually positions itself below the occlusal plane. This causes functional and esthetic problems, and orthodontic treatment is often impossible. To clarify this problem, we developed a new treatment protocol for the movement of ankylosed teeth. This consists of single-tooth dento-osseous osteotomy and alveolar bone distraction using orthodontic multibracket appliances. A special distraction device is not required, thus reducing the burden to patients. Two cases in which an ankylosed maxillary central incisor was successfully treated with this protocol are presented.

Evaluation and analysis of formation of bone at the palate in patients with cleft lip and palate after palatoplasty based on computed tomograms and three-dimensional data.

There are various techniques for palatoplasty, but no studies of postoperative osteogenesis at the palatal fissure. In the cranial and maxillofacial region it is thought to develop from the periosteum, so palatoplasty with mucoperiosteal flaps may encourage new bone to form at the fissure. We evaluated the status of osteogenesis in the hard palate after palatoplasty on computed tomograms (CT). We studied 29 patients (22 boys and 7 girls) with unilateral cleft lip and palate who had pushback palatoplasty with the use of CT obtained between May 2003 and March 2007. Age at the time of operation was recorded. The width of the palatal fissure at the first premolar, the first molar, and the maxillary posterior region were measured on coronal CT. The mean (SD) age at the time of palatoplasty was 16 (2) months. The mean (SD) width of the fissure at the first molar was 3.96 (3.1) mm, and bony union was seen in four patients. The width of the fissure was significantly less at the first molar than at the other sites (p = 0.006). The shape of the margin of the fissure was irregular in nearly all patients. The width of the fissure at the first molar became significantly less, suggesting that osteogenesis had occurred. In some patients the height of the fissure differed. Given the results of previous studies, bony regeneration from the periosteum most likely happens together with regeneration from the margins of the fissure.

Evaluation of 15 mandibular reconstructions with Dumbach Titan Mesh-System and particulate cancellous bone and marrow harvested from bilateral posterior ilia.

This study reports on 15 mandibular reconstructions using the Dumbach Titan Mesh-System and particulate cancellous bone and marrow harvested from bilateral posterior ilia. All cases showed segmental defects. Eleven cases involved patients with malignant tumor. Six patients had received irradiation of 40-50 Gy. Reconstructions were performed immediately in 1 patient and secondarily in the remaining 14 patients. In 13 cases, mandibles were successfully reconstructed. Of these 13 patients, 9 reconstructions were completed without complications, whereas the other 4 cases showed complications. In 2 cases, reconstruction failed completely. Overall success rate was 87%. Statistical analysis revealed the extent of mandibular defect, but not malignancy of the original disease or radiotherapy of

[Clinical application of bone regeneration by in vivo tissue engineering].

With regard to the graft materials, cortical bone block, vascularized bone flap and particulate cancellous bone and marrow (PCBM) have been used for the reconstruction of maxillofacial skeleton. Needless to say, the aim of cortical bone block and vascularized bone flap transfer is the transplantation of bony tissue of its own. On the other hand, the main objective of PCBM grafting is the transplant of osteogenic stem cells derived from uncommitted marrow mesenchymal cells. After PCBM grafting, active new bone formation occurs from osteogenic stem cells followed by bone remodeling and replacement of host bone. This process means that PCBM grafting is the method of bone regeneration that is based on in vivo tissue engineering. In this paper, clinical application of PCBM grafting for the reconstruction of maxillofacial skeleton is introduced by showing the repair of maxillary bony defect of cleft lip and palate patients, alveolar ridge augmentation and the reconstruction of large mandibular segmental defects.

Biosynthesis, processing, trafficking, and enzymatic activity of mouse neprilysin 2.

Neprilysin 2 (NEP2) has been recently identified as a new member of the M13 subfamily of zinc-dependent metalloproteases and shares a highly homologous amino acid sequence with neprilysin (EC 3.4.24.11, NEP). NEP2 has been reported to exist as membrane-bound and soluble secreted variants. To investigate mechanisms of regulating NEP2 activity, we developed a simple and sensitive method for measuring NEP2 activity using synthetic substrates with a fluorescent probe. NEP2 only cleaved Suc-Ala-Ala-Phe-AMC, while NEP cleaved both Dansyl-D-Ala-Gly-p-nitro-Phe-Gly and Suc-Ala-Ala-Phe-AMC. Using HEK293 cells stably expressing mouse NEP2, we evaluated the effects of various reagents affecting post-translational modification and protein trafficking on extracellular NEP2 activity secreted into the culture medium. Inhibition of N-glycosylation by tunicamycin reduced both the enzymatic activity of extracellular NEP2 and the molecular size of intracellular NEP2. Disruption of the Golgi apparatus with brefeldin A markedly reduced extracellular NEP2 activity in parallel with intracellular NEP2 protein level in HEK293 cells. In contrast, the cytoskeleton disrupting reagents, nocodazole and cytochalasin B barely affected NEP2 activity. Two distinct calcium-perturbing reagents, a calcium ionophore A23187 and thapsigargin, reduced extracellular NEP2 activity. However, A23187-mediated down-regulation was not rescued by co-treatment with inhibitors of MAPK, calmodulin, or the proteasome/calpains. In conclusion, we established a simple and sensitive protocol which was able to discriminate NEP2 and NEP activity, and showed that intracellular transport and secretion of NEP2 is regulated by processes such as glycosylation, ER-Golgi transport, and intracellular calcium levels.

Immunohistochemical localization of matrix metalloproteinase 13 (MMP-13) in mouse mandibular condylar cartilage.

MMP-13 appears to be one of the most important MMPs in cartilage remodeling and mineralization, because it exhibits a substrate preference for the cartilage-specific type II collagen. The condylar process is constructed by rapid accumulation of hypertrophic chondrocytes during development, but its mechanism is still unclear. To investigate the role of MMP-13 in developing condylar cartilage, we immunohistochemically examined the localization of MMP-13 in the endochondral ossification of the mandibular condyle and tibiae of newborn mice. In the tibiae, the MMP-13 expression was detected only in the deepest layer of the terminal hypertrophic chondrocytes through every examined stage (day 1 to day 10 after birth). On the other hand, in the condylar cartilage at days 1 and 5, MMP-13 was expressed throughout the proliferating and the hypertrophic chondrocytes, and at day 10, MMP-13 was mainly localized in the deepest edge of the hypertrophic layer. A zymographical study showed that the activity of MMP-13 in the condyle was observed at day 1, earlier than in the tibia, and increased until day 7. The time-dependent and cell-specific expression of MMP-13 and its enzymatic property suggest that in the mandibular condylar cartilage, MMP-13 plays a role in making the space for cell enlargement by degradation of the cartilage matrix and in onset of mineralization during the early stage of development.