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S R Pollack

Publications and source records attributed to S R Pollack.

59 records · Page 4Linked to original sources
PubMedDate not supplied

Surgically modelled reduced ridge in the beagle dog.

A reproducible surgical method for the production of reduced alveolar ridge in dogs using guided tissue regeneration principles is described. 3 defects resembling a reduced ridge were formed on both sides of the mandible in 4 dogs. In each of the dogs, a polytetrafluoroethylene membrane was placed on 4 defects, while 2 defects were covered by gingival flaps only. Half of the defects were allowed to heal for 6 weeks and half for 12 weeks. Bucco-lingual width measurements revealed healing up to the membrane. In the uncovered defects, the bony wall width increased during the 12-week healing period. Histological examination showed close adaptation between bone and membrane in well-sealed defects. In cases of incomplete sealing, connective tissue had penetrated into the defect, resulting in unpredictable bone healing. The use of guided tissue regeneration techniques is suggested as a valuable tool in creating experimentally reduced ridges.

Alveolar Bone Loss↗
PubMedDate not supplied

An in vitro study of electrical osteogenesis using direct and pulsating currents.

Although many investigators have electrically stimulated osteogenesis in vivo, this phenomenon has not been reported in vitro. In this work direct and pulsating currents were applied to in vitro fetal rat tibiae. The results indicated that electric current did cause osteogenesis in vitro, precipitates of calcium compounds formed in the cathode region, and direct current was more effective in stimulating bone growth than pulsed current delivering the same total charge (coulombs).

Animals↗
PubMedDate not supplied

Stiffness and strength of fracture callus. Relative rates of mechanical maturation as evaluated by a uniaxial tensile test.

Mechanical evaluation of healing fractures in rabbits suggests that tensile testing both minimizes artifacts and permits direct intrinsic determinations of tissue quality. In healing osteotomies in the rabbit fibula, there is a rapid return of stiffness at 16 days, correlating with callus maturation. The failure mode proved to be a "delamination" fracture. Values for the strength of bone (3.3 N/m2) and fibrocartilage (0.2 N/m2) correlate well with the results of other studies but are probably values of maximum tissue adhesion strength.

Animals↗