[Purpose] To develop a digital radiographic bone trabecular structure analyzing system and to applied it to mandible. [Methods] Structural change was simulated by removing spongy bone in human dried mandible. Using a morphological filter processing, the skeletal features were extracted from digital radiographic image data obtained by computed radiography before and after the removal of spongy bone. The skeletal volume, surface, thickness, number, separation, complexity, spacing continuity and connectivity on the skeletal binary images were determined by morphometric indices calculation, star volume analysis and node-strut analysis. Using these quantified skeletal feature parameters, a mapping sheet for the structural evaluation was produced. The correlation between the fluctuation rate of each parameter after the removal of spongy bone with respect to the value before the removal of spongy bone and simulated structural change was examined. [Results] The skeletal binary image data quantified sixteen skeletal feature parameters using morphometric indices calculation, star volume analysis and node-strut analysis. These parameters agreed with the theoretical fluctuation pattern in the simulated skeletal structure deterioration of the mandibular bone trabeculae. [Conclusion] Using a morphological filter and bone histomorphometry, the radiological bone-morphometric analyzing system is useful for the evaluation of the mandibular trabecular structure.

Cat cry syndrome (cri-du-chat syndrome) is an extremely rare condition characterized by a high shrill cry during infancy, resulting from either the deletion of the short arm of chromosome 5 or unbalanced translocation inherited from a parent. We report the case of a 1-year-old girl with cat cry syndrome associated with cleft lip. The patient showed a ventricular septal defect, cleft lip, growth and mental retardation, micrognathia, ptosis of the eyelids, hypertelorism, epicanthal folds, and a preauricular tag on the right side. A chromosomal study revealed the terminal deletion of chromosome 5 (46, XX, del(p14.2)ish del(5)). Repair of the cleft lip was carried out concurrently with resection of the preauricular tag, and the patient's postoperative course was uneventful.

This study was intended to determine whether mouth-opening exercise reduces pain sensitivity in remote regions as well as in the trigeminal region. Seven female subjects with disk displacement with reduction were asked to perform a three-minute repetitive mouth opening and closing exercise (exercise A) and a three-minute continuous mouth opening exercise (exercise B) on two separate days. Sensory/nociceptive perception thresholds were measured at the point over the right masseter and the skin overlying the volar aspect of the right forearm immediately after exercises A and B, and were compared to data in which no exercise was performed (baseline). Significant elevation in the heat-induced pain threshold was seen as a result of both exercises in the cervical region and in the trigeminal region. Also, a significant elevation in the cold-induced pain threshold was seen after exercise B in the cervical region. Further, there was a tendency toward a higher warm sensation threshold after exercise A in the cervical region. These results indicate that mouth opening training produces non-segmental analgesic effects mediated by C fiber and A-delta fiber.