RESUMO
<p><b>OBJECTIVE</b>To analyze the effects of nicotine on the bone calcium and phosphorus content and alkaline phosphatase (ALP) activity in rat alveolar bone and mandible.</p><p><b>METHODS</b>Twenty health male Wistar rats of five weeks of age were randomly assigned to two groups and received daily intraperitoneal injections for three months as follows: Saline solution for control group, nicotine 0.73 mg.kg-l.d-1 for experimental group. The bone calcium phosphorus content were detected by concentrated acid digestion method and the ALP activity was examined by improved Reddi method.</p><p><b>RESULTS</b>Compared to the control group, bone calcium and phosphorus content was lower in the experimental group (P<0.05), ALP activity had no statistical significance(P>0.05). Bone calcium phosphorus and ALP activity in different parts had no statistical significance (P>0.05).</p><p><b>CONCLUSION</b>The nicotine reduces calcium phosphorus deposition of jaw bone, but has no obvious influence to ALP activity.</p>