Longitudinal study on torque around the sagittal axis in lower distal-extension removable partial dentures.
The purpose of this study was to examine the longitudinal changes of torque around the sagittal axis in lower distal-extension removable partial dentures. The torque transmitted from the denture base to retainers was measured on several separate occasions from the insertion of new dentures to about 2 months after it. The maximal mean value of torque (Max.MT) was calculated from the magnitude of all chewing strokes of the minimum of the interocclusal distance. The integration values of torque (I) and time (T) from initiation of chewing to swallowing were obtained and then the average value of torque (Ave.T) was calculated (Ave.T = I/T). Subjects could be divided into two groups. Max.MT and Ave.T were almost constant in one group while they were remarkably decreased in another. After 1 month of insertion of new dentures the value of both groups was within the range of less than 3 x 10(-3) kgm (1 kgm = 9.8 Nm) of Max.MT and less than 1 x 10(-3) kgm ss-1 of Ave.T.
Ogata
K
K
Department of Removable Prosthodontics, Okayama University Dental School, Japan.
D000328:Adult; D000368:Aged; D000044:Dental Abutments; D003799:Dental Stress Analysis; D003832:Denture, Partial, Removable / Q000009:adverse effects*; D005502:Food; D006801:Humans; D007576:Jaw, Edentulous, Partially / Q000503:physiopathology*; D008334:Mandible / Q000503:physiopathology; D008409:Mastication; D008875:Middle Aged; D012399:Rotation; D013997:Time Factors; D014159:Transducers