Managing stage III and IV periodontal disease (Proceedings)
Correct management of periodontal patients in veterinary practice demands a thorough understanding of veterinary dental radiographic anatomy, periodontal probing and many times open evaluation and direct visualization of diseased areas. Stage III periodontal disease in particular requires advanced skills and familiarization with periodontal pathophysiology to make decisions to attempt to grow new supportive tissue adjacent to compromised teeth or extract them.
Periodontal Disease Classification
Stage III periodontal disease as described represents a 25 50% loss of the tissue supporting the root. Three tissue types become clinically relevant; bone, cementum and periodontal ligament. Depending upon the character of the bone loss, with proper surgical and postoperative management new tissue can be grown to replace or partially replace that which has been lost. The character of the bone loss is primarily determined radiographically.Vertical or infrabony bone loss is represented radiographically by a defect adjacent to the tooth root whereby a periodontal probe when passed into the defect resides apical to the level of the adjacent marginal bone. The radiographic void is grossly filled with granulation tissue. Cementum and periodontal ligament are no longer present. Dentin is exposed often with open tubules creating access or microbes to this passage-way to the pulp. Horizontal bone loss is recognized when the bone loss pattern is more uniform whereby a periodontal probe passed into the defect resides on top of the marginal bone level rather than apical to it. These defects commonly are associated with gingival recession exposing tooth roots. These roots are generally void of cementum leaving open dentinal tubules that are exposed to periodontal pathogens as described with vertical defects. This in an important point in both cases in that endodontic status should always be assessed when contemplating periodontal surgery in stage III defects. Periapical lucencies or comparatively large pulp cavities are indications of non-vitality. If these teeth are to be saved endodontic therapy is also required and usually caries a guarded prognosis.
Horizontal defects are not readily amenable to periodontal regenerative therapy. If recession is not present then apically positioned mucoperiosteal flaps following debridement, treatment of exposed roots and bone contouring may be possible. This requires exposure of the affected area through mucoperiosteal flap creation. The defect is debrided to the level of the marginal bone. Proper bone contouring is followed by apical positioning of the flap at the new bone level. Roots are treated with bonding agents to seal the dentinal tubules to eliminate microbe extravasation and sensitivity.