Background Larsen syndrome (LS) is a rare disorder of osteochondrodysplasia. In addition to large-joint dislocations, craniofacial anomalies are typical characteristics. In this report, we performed orthodontic analyses, including skeletal and occlusal evaluations, to examine whether the craniofacial skeletal morphology leads to the craniofacial anomalies in LS. Case presentation A 5 year old Japanese girl who was clinically diagnosed with LS was referred to the orthodontic clinic in the Fukuoka Dental College Medical and Dental Hospital because of a malocclusion. Clinical findings at birth were knee-joint dislocations, equinovarus foot deformities, and cleft soft palate. The patient showed craniofacial anomalies with hypertelorism, prominent forehead, depressed nasal bridge, and flattened midface. To evaluate the craniofacial skeletal morphology, cephalometric analysis was performed. In the frontal cephalometric analysis, the larger widths between bilateral points of the orbitale were related to hypertelorism. The lateral cephalometric analysis revealed the midface hypoplasia and the retrognathic mandible. These findings were responsible for the flattened appearance of the patient’s face, even if the anteroposterior position of the nasion was normal. Her forehead looked prominent in relation to the face probably because of the retrognathic maxilla and mandible. Both the study model and the frontal cephalometric analysis indicated constriction of the upper and lower dental arches. The posterior crossbite facilitated by the premature contacts had developed in association with the constriction of the upper dental arch. Conclusions This patient had some craniofacial anomalies with characteristic appearances in LS. It was evident that the underlying skeletal morphology led to the craniofacial dysmorphism.

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Objective: This study examined the factors related to the morphogenesis of the craniofacial complex of the CL/Fr mouse fetus affected with CLP based on the findings of a lateral cephalogram. Design: Embryo transfer experiments were performed to determine the effect of the fetus weight, dam strain, dam weight, and litter size on the intra-uterine craniofacial morphogenesis of CL/Fr mouse fetuses. On the 18th gestational day, each pregnant dam that had received CL/Fr mouse embryos was laparotomized to remove the transferred fetuses that had developed in the uteri of the cleft lip and palate (CLP)-susceptible CL/Fr strain dam and the CLP-resistant C57BL strain dam. A cephalometric observation of the craniofacial morphology of each fetus was subsequently performed. Results: Based on a multiple regression analysis, the standardized partial regression coefficients of the affected fetus weight, the dam weight, and the litter size on the maxillary size of the affected CL/Fr fetus were 0.71 (p < .01), 0.03, and −0.07. According to a least-squares analysis of variance, the dam strain effect in addition to the effect of the affected fetus weight on the maxillary size and the cranial size of the affected fetuses was significant (p < .01 for cranial size, p < .05 for maxillary size) and close to a significant level (p = .09) for the mandibular size of the affected fetuses. The adjusted maxillary size and cranial size after statistically eliminating the effects of the affected fetus weight, dam weight, and lifter size on each original craniofacial size of the affected fetuses that had developed in the CL/Er dam strain were also significantly smaller than those of the affected fetuses that had developed in the C57BL dam strain. Conclusions: The present results indicate that the craniofacial growth of the CL/Fr mouse fetus affected with CLP increased in proportion to the fetus weight. The dam strain effect, in addition to the effect of the affected fetus weight, could thus not be ignored when the etiology of the spontaneous CLP was examined, while the uterine environment, provided by the CL/Fr strain dam, retarded the intra-uterine craniofacial growth of the affected fetuses. It was therefore concluded that the dam strain effect, as well as the effect of the affected fetus weight, both play an important role on the craniofacial morphogenesis of the CL/Fr strain of the affected fetuses that developed in both strain dams.

This report presents a case of eruption guidance for an upper right central incisor with a dentigerous cyst associated with an impacted supernumerary tooth in a 5-year-9-month-old boy. A swelling was seen in the region of an upper right central incisor. Radiographic examinations showed that a well-defined cystic lesion, containing an impacted supernumerary tooth crown in it, was located between the root of the primary upper right central incisor and a permanent upper central incisor germ. Under general anesthesia, the dentigerous cyst was removed at extraction of the upper impacted supernumerary tooth. And then, a socket was kept open wound. A histopathological examination confirmed the diagnosis of a dentigerous cyst associated with a supernumerary tooth. By using an obturator, we guided eruption of an upper right central incisor with malposition that was caused by the dentigerous cyst, and observed the way of the tooth eruption for two years and seven months. The obturator was inserted in the socket directly for three months until it was closed. After that, the obturator was used as only a removable space maintainer. Eight months after the operation, the obturator was removed because the upper left central incisor began to erupt. Two years and seven months after the operation, both upper central and lateral incisors had erupted completely. In this case, the obturator was used for expectation of natural eruption of permanent incisors, space maintenance and aesthetic recovery. The permanent incisors had been able to be guided to almost correct position without traction. some difficulties to do those treatments in pediatric dentistry, because some patients are uncooperative for earlier age, or some patients in mixed dentition period needing eruption guidance. Nevertheless it is necessary to treat correctly with those cases in order to develop the normal permanent dentition. In this case, we treated a 5-year-9-month-old boy with a dentigerous cyst caused by an impacted supernumerary tooth. The dentigerous cyst was removed at extraction of the upper impacted supernumerary tooth, and the socket was kept open wound. By using the obturator, we guided eruption of the upper right central incisor with malposition caused by dentigerous cyst. And then we observed for two years and seven months.