Placement of a porous membrane underneath the mucoperiosteal flap and its effect on periodontal wound healing in dogs.

This study was designed to investigate the healing of surgically induced, horizontal periodontal defects in dogs following placement of a biocompatible, porous polytetrafluorethylene membrane around the roots of the treated teeth and to compare the healing to that of control teeth without membrane. Mandibular premolar teeth of 5 beagle dogs were used for experimentation. Specimen blocks were removed 3 months postoperatively for histological evaluation of contralateral experimental and control teeth. Mean apical migration of junctional epithelium among the experimental surfaces amounted to 0.1 mm as compared to 1.3 mm for the control surfaces. Accordingly, the amount of connective tissue attachment, defined by the distance from the base of the junctional epithelium to the apical termination of root planing, was greater for experimental than for control surfaces. As this increased amount of connective tissue attachment was associated with more coronal bone apposition, a periodontal ligament space was more prevalent in experimental than in control surfaces. A limited amount of ankylosis was observed for both experimental and control surfaces. Root resorption was more prevalent in control than in experimental surfaces. Conceivable reasons for the differences in healing between experimental and control teeth are discussed.