Comparative Evaluation of Marginal Bone Level Changes in Delayed and Early Implant Placement

Background: The aim of modern dentistry is to restore the patient’s health with predictable techniques. Implant-supported prostheses can be used to restore the patient’s function, comfort, esthetic, speech, oral health and the integrity of tooth with adjacent hard and soft tissues to some extent. Intraosseous implants can be placed using three different techniques, including the immediate, the early and delayed technique. Due to the longer healing period and formation of bone in the delayed technique, it is hypothesized that the marginal bone around the implants will undergo less resorption compared to the early technique. Objectives: The aim of this retrospective study was to compare the changes in the levels of marginal bone around implants placed using early and delayed implant placement techniques. Patients and Methods: In the present retrospective cohort study, 38 implants from the BEGO system were used. These implants were placed in 17 patients in 2 different groups. In group 1, 20 implants were placed early (1 - 2 months after extraction), and in group 2, 18 implants were placed with a delay of more than 4 months after tooth extraction. The marginal bone level was measured on periapical radiographs taken using the parallel technique at three different intervals: at implant placement time, and 6 and 12 months after implant placement. The measurements were made using a digital caliper with an accuracy of 0.01 mm, and the data were analyzed using a repeated-measures ANOVA in association with Mauchly’s sphericity test. The statistical significance was set a P < 0.05. Results: Themean distances between the crestal bone and the implant shoulder in group 1 were 1.01, 1.44, and 1.93mm at the implant placement time, and at the 6 and 12-month postoperative intervals, respectively. In group 2, these distances were 1.35, 1.20, and 1.41 mm, respectively. There were no significant differences in the marginal bone resorption between the two groups (P > 0.05). Conclusions: The amount of crestal bone loss around the implants placed early was greater than that around the implants placed with a delay; however, the differences were not significant.