The effect of elimination of jiggling forces on periodontally exposed teeth in the dog.

The aim of the present investigation in dogs was to analyze the effect on periodontal disease induced by a combination of ligatures and jiggling trauma, when the jiggling forces are eliminated. The experiment was performed in six dogs. On Day 0 a phase of periodontal tissue breakdown was initiated around the mandibular fourth premolars (4P; P4) by placing plaque retention ligatures around the necks of the teeth. The ligatures were changed once a month during a 90-day period. On Day 90 the ligatures were removed. On Day 0 trauma from occlusion (jiggling) was also produced in the 4P and P4 region. On Day 90 the jiggling trauma was removed from the 4P-region (test) while it was maintained in the P4-region (control). Tooth mobility measurements and radiographic examinations were carried out on experimental Days 0, 30, 60, 90, 180, and 360. One dog was sacrificed on Day 90 and the remaining five on day 360. Following sacrifice, tissue sections comprising 1M, 4P, 3P, P3, P4, M1 were obtained and subjected to microscopic analysis. Removal of the jiggling trauma from the test teeth resulted in a markedly decreased tooth mobility, but the loss of connective tissue attachment on Day 360 was similar in the test and control sites. This means that although the control teeth had an increased mobility and a widened periodontal ligament space, the height of the remaining periodontal tissue support was similar in the test and control tooth regions.