Alendronate is a bisphosphonate frequently used to reduce bone resorption. It has been used for osteoporosis, Paget's disease, and also as adjunctive therapy for periodontal disease. The aim of this study was to evaluate the effect of systemic alendronate with or without endoalveolar collagen sponge on vertical bone resorption after lower wisdom tooth extraction. Forty patients referred for wisdom tooth impaction were selected. Before surgery, patients were randomly assigned to receive one of the following pharmacologic treatments: no medication (group 1), postextractive endoalveolar collagen sponge (group 2), systemic alendronate for 4 months starting the day of surgery (group 3), and group 2 + group 3 (group 4). Standardized orthopantomographic evaluation was obtained during recruitment (T1), immediately after surgery (T2), and 4 months (T3) to evaluate crestal and alveolar socket changes. Results indicate that at T2, crest and socket level did not show significant differences between the four groups. At T3, test sites treated showed less bone resorption compared with controls. In particular, higher vertical bone height levels and a faster intraalveolar healing were achieved in groups 3 and 4. Systemically given alendronate may be used successfully to reduce vertical bone resorption after wisdom tooth extraction.