Probing pocket depth at mobile/nonmobile teeth.

Abstract

The aim of the present investigation was to study the influence of an increased tooth mobility on the resistance offered by the periodontal tissues to probing. 6 beagle dogs were used. At the start of the experiment, the animals had clean teeth and normal gingival and periodontal conditions. In each dog, a device was installed in the lower left jaw quadrant to expose the third premolar (P3) to jiggling forces which would enhance the mobility of this "test" tooth. The contralateral tooth served as the non-jiggled control. During the 3 months of experimentation, the teeth of the dogs were cleaned on a regular basis. Clinical examinations including tooth mobility measurements were performed on days 0 and 90. After the examination on Day 90, a probe was inserted in the buccal "pocket" of the mesial root of 3P and P3. The probe was retained with composite. Biopsies including the test or control tooth with adjacent buccal periodontal tissues were harvested, fixed and decalcified. Each biopsy was divided in one mesial and one distal portion (root). The distal portion was embedded in Epon, sectioned and stained in PAS and toluidine blue, while the mesial portion, following probe removal was embedded in paraffin, sectioned and stained in hematoxylin-eosin. The sections were exposed to histometric and morphometric measurements. The findings demonstrated that tissue alterations which occur at mobile teeth may reduce the resistance offered by the periodontal tissues to clinical probing. Such alterations include (i) reduced height of the alveolar bone, (ii) reduced amount of collagen, and increased vascularity in the enlarged supracrestal connective tissue.