Background: Crestal bone level surrounding a dental implant is a dynamic structure due to bone remodeling and possible bone loss after implant loading. The study aims to compare the bone changes around single implants 1.8 mm machined collar soft tissue level versus bone level implant with nonmachined collar all roughed surface placed either in the maxilla or the mandible at 3–6 years
Materials and methods: A randomized controlled clinical trial was conducted among 100 patients needing dental implants. The participants were randomly divided into two study groups; group 1 received bone level implants. Group 2 received soft tissue level implants (1.8 mm machined surface). After three months of the healing period, the implants were loaded with a screw-retained single crown. The initial measurement was done at three years and repeat measurements were recorded after six years. Statistical analysis was performed by paired sample t-test and independent sample t-test. Statistical significance was considered at α = 0.05.
Results: The bone measurements for the soft tissue level implant at three years and six years were 0.556 ± 0.2742 mm and 1.172 ± 0.6128 mm, respectively while those for the bone level implant were 0.668 ± 0.3178 mm and 1.366 ± 0.8163 mm, respectively. The intragroup comparison revealed that there was a statistically significant rise in the measurement at the 6-year evaluation as compared to the three-year evaluation for both the type of implants. However, the intergroup comparison revealed no statistically significant difference in the bone measurement between the two implant types at both three years and 6-year measurements.
Conclusion: There is no difference in the bone changes around single implants placed either at soft tissue level or at the bone level.
Clinical significance: The choice of implant should be based on the esthetic requirement of the patient as well as the clinician\'s expertise.
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