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This study explored the pressure pain threshold (PPT) of the mucosa after tooth extraction. The PPTs of the wounded mucosa of eight volunteer subjects were observed at 7, 30, and 90 days after tooth extraction. The PPTs at 30 days and 90 days were approximately two and three times higher respectively, than those at 7 days. As time passed, the values for the PPTs after tooth extraction increased in all regions. At 90 days after tooth extraction, the PPTs are about 97% recovered compared to the PPTs of the contralateral points.

This three-dimensional finite element analysis first described stresses distribution in loaded posterior fixed partial dentures, then compared the influences of bone height, abutment roots number and pontic length on their displacements. Twelve mandibular (three to five unit) FDPs integrating periodontal ligaments were designed. Stresses were localized in connectors and cervical areas of abutments near the edentulous span. The main FDPs' displacements consisted of vertical translation increasing with low bone height. FDPs underwent simultaneously an anteroposterior displacement (about ten times smaller) towards the weakest abutment side. Splinted abutments affected this anteroposterior displacement. Span length was associated with small beam deflection.

This study aimed to assess the level of restored occlusal support by removable partial dentures with free-end saddles. The maximal clenching force of 61 subjects was measured using pressure sensitive film with and without their dentures. The restored level of occlusal support was estimated from the shift of the occlusal load centre. In comparison with previous results of experimental occlusions using splints for eight normal dentate subjects, the restored level using dentures ranged from 40-60% of that of natural teeth. The analysis of the shift of the occlusal load centre could reasonably evaluate the prostheses from the standpoint of occlusal support.

Three-dimensional mandibular displacement related to loss of posterior occlusal support was investigated. Five subjects, whose mandibular premolars and molars needed to be restored, were selected. Their experimental prostheses were removed in sequence from the most posterior to anterior. The more the absence of posterior occlusal support increased, the more condylar displacements were increased. On the other hand, maximum bite forces were decreased, by removing each prosthesis in sequence from posterior to anterior. These results suggest that condylar position would be easily displaced with low level bite force following loss of posterior occlusal support.

The aim of this in vivo study was to compare the precision of control of jaw closing forces through implants versus natural teeth. Ten partially dentate subjects with fixed implant prostheses in their mandibles took part in the study. A force transducer was used to assess the ability of the subjects to follow pre-determined jaw closing cycles. The error in tracking the target increased as the force increased for both implant and tooth sites. Within the range of forces tested, there was no significant difference in the error between the implant and natural tooth sites.

The aim of this study was to investigate the effect of the loss of posterior teeth on the effectiveness of mastication. To evaluate this, chewing performance and occlusal contact area were investigated in 10 edentate subjects having implants stabilising a mandibular overdenture. A copy of the original lower denture was made for each subject, with removable teeth, which could be separated to convert a complete dental arch to a shortened dental arch, an extremely shortened dental arch, or a broken dental arch. Both post canine occlusal contact area and chewing performance demonstrated significant differences between the different arches. It was concluded that chewing performance is reduced by removing posterior teeth from implant stabilised mandibular complete dentures.

Forces exerted on the right and left lingual and buccal flanges of Kennedy Type I mandibular dentures were studied using an 8 channel recording technique, during resting, swallowing, talking, reading and simulated mastication. The effects of adaptation, head position and incremental thickening of the flanges were determined. Highest forces were recorded when swallowing, with smaller differences between the other activities. Lingual forces were higher than buccal, and posterior forces higher than anterior ones. There was a highly significant relationship between increases in flange thickness of 2 and 3mm and increases in peak forces. Evidence for adaptation and effects related to head position was weaker.