Initial clinical efficacy of 3-mm implants immediately placed into function in conditions of limited spacing.

Purpose: The objective of this study was to determine changes in interdental papillae, alveolar bone loss, esthetics, and initial healing survival when 1-piece narrow-diameter implants were immediately loaded in sites with limited tooth-to-tooth spacing.

Materials And Methods: One-piece titanium alloy implants with a maximum diameter of 3.0 mm and a resorbable blast surface texture on a square-thread form were evaluated. Digital photographs were made at each clinical visit to assess soft tissue healing. Interproximal soft tissue fill of the embrasure was assessed with a modified Jemt index. Standardized radiographs were made at baseline (implant placement) and at 6 and 12 months postsurgery. Radiographic bone height was measured from a consistent landmark on the implant. A 1-sided t test was used to determine statistical differences of bone height.

Results: Thirty-one implants were placed in 17 subjects. One implant had clinical mobility and was removed, for an overall survival rate of 96.7%. Mean bone height on the day of placement and restoration was 2.33 + 0.73 mm above the first thread. Mean bone height was 1.75 +/- 0.78 mm at 6 months postrestoration and 1.63 +/- 0.81 mm at 12 months postrestoration. There was a statistically significant loss of bone support over the initial 6 months (0.58 mm; P < .01), with no significant progression thereafter (0.12 mm; NS). Complete fill of papillae was found in 92% of maxillary lateral incisor sites and 60% of mandibular incisor sites.

Conclusion: The use of 1-piece narrow-diameter immediately loaded implants appears to be an effective prosthetic treatment for areas of limited space.