Abstract: Objective: To evaluate the vertical bone resorption of labial bone in anterior maxillary implant by bone splitting technique. Methods: 19 patients (8 men, 11 women) whose ages ranged from 22 to 65 years, were included in this study. The labial-lingual thickness of alveolar was from 3.0 to 5.0mm for everybody, 26 Ankylos implants (3.5mm)were placed after splitting the bone immediately and constructed with the operation of guided bone regeneration, CBCT were taken after crown setted immediately and two years later to observe the labial bone resorption. The value of the labial bone resorption and gingival recession were calculated and analysed and the correlation between these changes were detected in SPSS 11.0. Results: Both vertical bone resorption and gingival recession showed a significant negative correlation to cervical width. As expected, vertical bone resorption and gingival recession showed a significant positive correlation. Conclusion: It is suggested that alveolar bone thickness after implant placement in the anterior region could be negatively associated with the level of alveolar bone resorption at the labial aspect as well as gingival recession.

Key words: Cone beam computed tomography, Maxillary anterior implants, Bone resorption, Bone splitting technique