Inclusion Criteria:  At least 1 tooth having missed within 3-4 months or to be extracted in anterior zone, and the remaining teeth are adequate to support the surgical template. Sufficient bone tissue to insert an implant without any need for augmentation (the residual bone height ≥ 10 mm, the buccolingual width ≥ 7 mm, and the labial bone plate is complete without bone dehiscence and fenestration). Good treatment compliance.  Exclusion Criteria:  Presence of uncontrolled systemic diseases, infection, or inflammation around the implant sites. Pregnancy or lactation. Poor oral hygiene habits. Psychiatric problems, alcohol, tobacco (>10 cigarettes per day) or drug abuse. Severe bruxism or clenching. Not able to complete the follow-up.