Tooth dimensions in Filipinos were investigated using odontometric methods. Materials used were dental casts taken from Tagalog males living in Manila, the Philippines. Casts of Japanese were measured as comparative data. Mesiodistal and buccolingual crown diameters were measured for each of the 14 teeth of permanent dentition using a digital caliper (0.01 mm). 1. Comparison between Filipinos and Japanese dentition : The mesiodistal crown diameters of the incisors were smaller in Filipinos than in Japanese, but the buccolingual diameters were larger. The canines and premolars were larger in Filipinos than in Japanese, but the molars were smaller in Filipinos. Crown indices showed that the Filipinos had relatively larger buccolingual diameters than Japanese with the exception of the premolars. 2. Comparison with other Mongoloid populations : Southeast Asian sundadonts including Filipinos had larger tooth dimensions than the typical sundadonts, such as Jomon natives and their lineage, but the shapes in sundadonts were similar. Regarding tooth shape, the reduction index in the molars effectively divided the sundadont and sinodont dental groups.
By using commercial dentifrices for sensitive teeth, automatic two-dimensionally rotated toothbrushing was performed on the tangential ground surfaces of human sound dentin in the cervical regions for 10 min in vitro. The dentin surfaces were observed with scanning electron and scanning laser microscopes. The brushing caused remarkable abrasion with the traces of toothbrush bristles on account of the abrasive agents, while most of the dentinal tubules were occluded with dentin sludge or covered with smear layers. Therefore, daily toothbrushing with such dentifrices will promote the formation of wedge-shaped defects in the cervical regions, even if the dentin hypersensitivity is decreased temporarily due to the occlusion of the exposed tubules.
Muscle/periosteal flaps were raised and 4.5-mm defects were created bilaterally in the tibiae of 12 rabbits. On the test side, Polyglactin 910 woven mesh was placed over the defect and the flaps were sutured. The defect on the contralateral side served as a control. After healing periods of 4 days, 1, 2, 4, 8 and 13 weeks the animals were killed, and 15-μm, hematoxylin and eosin-stained, undecalcified sections were prepared and examined. By 8 weeks postoperatively the mesh-covered defect had thoroughly healed with new bone, whereas the control showed discontinuous new bone in the defect. The mesh had been completely absorbed. The results indicate that the mesh guides bone regeneration during the early stages of healing and is eventually absorbed.