Toshimoto Tengan

Immunohistochemical findings type I and type II collagen in prenatal mouse mandibular condylar cartilage compared with the tibial anlage

In growing animals the mandibular condylar cartilage serves not only as an articular but also as a growth cartilage, yet, condylar cartilage has some characteristic features that are not found in growth cartilage. For example, some reports suggest that type I collagen, which is not seen in the growth plate cartilage of long bones, is present in the extracellular matrix of condylar cartilage postnatally. Here, the condylar and limb bud cartilage of fetal mice was examined. The distribution of type I and type II collagen in condylar cartilage was already different from that in the limb bud at the first appearance of the cartilage. Type I collagen was demonstrated in the extracellular matrix of the condylar cartilage that first appeared on day 15 of gestation. However, the reaction for type II collagen was much weaker than that for type I collagen. On day 18 of gestation, type I collagen was still found throughout the cell layers but became gradually weaker with depth. Type II collagen was limited exclusively to the deeper layers at this stage. These findings are different from those in the limb bud cartilage, indicating a characteristic feature of the cells in the condylar cartilage present from the prenatal period.

Dental Arch Relationship Outcomes in One- and Two-Stage Palatoplasty for Japanese Patients With Complete Unilateral Cleft Lip and Palate

Objective To compare dental arch relationship outcomes following one- and two-stage palatal repair. Design Nonrandomized, clinical trial with concurrent control. Setting Hokkaido University Hospital. Patients Sixty-eight consecutively treated Japanese patients with complete unilateral cleft lip and palate. Interventions Thirty-one of the 68 patients underwent two-stage palatoplasty with delayed hard palate closure, and 37 patients underwent one-stage pushback palatoplasty. Main Outcome Measures Dental casts were taken at 4.9 to 6.3 (mean: 5.2) years of age in the two-stage group and at 4.0 to 6.3 (mean: 5.1) years of age in the one-stage group, and dental arch relationships were assessed using the 5-Year-Olds’ Index (5-Y) by four raters and the Huddart/Bodenham Index (HB) by two raters. Results Intrarater and interrater reliabilities evaluated using weighted kappa statistics were good or better for the 5-Y and HB ratings. The mean 5-Y score was 2.94 in the two-stage group and 3.13 in the one-stage group (P value was not significant). However, there was a significant difference in distributions between the groups (P < .05). The HB scores of molars were significantly greater in the two-stage group than in the one-stage group (P < .05). The rank correlation coefficients between the 5-Y and total HB score (ρ = −0.840, P < .01) and between the 5-Y and the score of the incisors in the HB (ρ = −0.814, P < .01) were significantly increased. Conclusions These results suggest that the anteroposterior relationship was not significantly different between the groups, but the transversal relationship was better in the two-stage group than in the one-stage group.

Articulation disorders associated with maxillary growth after attainment of normal articulation after primary palatoplasty for cleft palate.

Little attention has been given to the connection between maxillary growth and the emergence of articulation disorders among cleft palate patients who previously successfully attained normal articulation after undergoing primary palatoplasty. Follow-up assessment of 22 surgically treated unilateral cleft lip and palate patients who attained normal articulation before school entry revealed that, during mixed dentition, half the patients exhibited palatalized articulation and half retained normal articulation. To determine the possible effect on articulation of growth changes in dental arch dimensions, a comparison was made of deciduous dentition and mixed dentition oral cavity measurements. Indications are that palatalized articulation occurs in patients with a smaller anterior palatal volume, the presence of linguoversion teeth, and poorer growth ability. Results reveal the importance of early management of dental arch dimensions, and the need for periodic assessment and management of articulation even for patients who attain normal articulation subsequent to primary palatoplasty.

Dental and maxillofacial characteristics of six Japanese individuals with ectrodactyly-ectodermal dysplasia-clefting syndrome.

Objective Ectrodactyly-ectodermal dysplasia-clefting syndrome is a congenital anomaly characterized by ectodermal dysplasia, ectrodactyly, cleft lip and palate, and lacrimal duct anomalies. Because this syndrome is frequently accompanied by a congenital lack of teeth, narrow palate, and malocclusion, comprehensive orthodontic intervention is required. Design To highlight the specific dental and maxillofacial characteristics of ectrodactylyectodermal dysplasia-clefting syndrome, six Japanese individuals diagnosed with the syndrome are described here. Patients The subjects consisted of two boys and four girls (age range, 6.0 to 13.9 years) diagnosed with ectrodactyly-ectodermal dysplasia-clefting syndrome by medical and dental specialists. Their conditions included ectodermal dysplasia (hypodontia, microdontia, enamel hypoplasia, and abnormalities in hair and nails), cleft lip and/or palate, and ectrodactyly. Cephalograms, panoramic x-rays, and dental casts were taken; systemic complications were recorded at the first visit to our dental hospital. Results All individuals had severe oligodontia with 9 to 18 missing teeth. The missing teeth were mainly maxillary and mandibular incisors and second bicuspids, arranged in a symmetrical manner. Cephalometric analysis showed retruded and short maxilla due to cleft lip and/or palate. It is interesting that all individuals showed a characteristically shaped mandibular symphysis with a retruded point B. It is likely that this unusual symphyseal morphology is due to the lack of mandibular incisors. Conclusions This study demonstrates the presence of severe oligodontia in the incisal and premolar regions and describes a characteristic maxillary and mandibular structure in Japanese individuals with ectrodactyly-ectodermal dysplasia-clefting syndrome.