Bone regeneration in alveolar bone dehiscences produced by jiggling forces

The aim of this experiment was to achieve support for the hypothesis that bone resorption, induced by jiggling forces, leaves a component within the supracrestal soft tissue with a capacity of reforming bone. The maxillary lateral incisors and first premolars and the mandibular second premolars in two monkeys were used in the study. Using metal pins inserted into the neighboring teeth as retainers, orthodontic elastics were stretched and placed alternately around the buccal and lingual surfaces of each experimental tooth in order to produce jiggling forces. After 5 months of continuous jiggling, when bone dehiscences were produced on the buccal aspect of the teeth, the elastics were removed. After repositioning of the teeth a split thickness flap was raised. On one side of the jaw the soft tissue within the bone dehiscences was removed. At the contralateral teeth a sham operation was performed maintaining the soft tissue within the bone dehiscences. The monkeys were sacrificed 6 months after surgery. Tissue blocks containing test and control specimens were dissected free and prepared for microscopic analysis. The length of the supracrestal connective tissue attachment and the amount of coronal bone regeneration were assessed in the histological sections. It was found that buccal alveolar bone, reduced in height by jiggling forces, regenerated after discontinuation of the forces. When the soft tissue within the buccal bone dehiscences produced by the jiggling forces was surgically removed, the coronal regeneration of the alveolar bone was markedly reduced. These observations suggest that bone resorption, induced by jiggling forces, leaves a soft tissue component with a capacity of forming bone.