Influence of submandibulectomy on alveolar bone loss in rats

BACKGROUND: The incidence of dry mouth and its public health impact are increasing as the result of a progressively larger, medicated older population and because chronic diseases, like periodontitis, are prevalent pathologies among elderly patients. Periodontitis and continuous remodeling and rebuilding alveolar processes greatly affect the margin of the alveolar bone, and there is evidence indicating the role of submandibular glands in the regulation of immune/inflammatory reactions. The purpose of this study was to assess the effect of submandibular-sublingual complex ablation (Sx) on alveolar bone loss in rats submitted or not to ligature-induced experimental periodontal disease (EP). METHODS: Wistar male rats were submitted to Sx or sham operations (day 0). Two weeks later, unilateral EP was induced on the right mandibular first molars for 7 days with the contralateral side serving as control. Bone loss at the level of the dental pieces was estimated by bone histomorphometry on mesio-distally oriented sections of the molars and by the determination on lingual and vestibular mandibular surfaces of the distances from the cemento-enamel junction to the alveolar crest. RESULTS: Sx and EP significantly increased lingual and vestibular alveolar bone loss. Molars with EP exhibited greater lingual loss in Sx animals compared to those with the sham operation. EP induced similar interradicular bone loss in sham and Sx rats. CONCLUSION: Sx has a deleterious effect on the periodontal tissues, particularly marginal alveolar bone, indicating the importance of the submandibular/sublingual glands in maintaining healthy periodontal conditions.