A multicenter randomized comparative trial of implants with different abutment interfaces to replace anterior maxillary single teeth
DDS, PhD
Stallings Distinguished Professor, Department of Prosthodontics, University of North Carolina, Chapel Hill, North Carolina, USA.
DDS
Department of Oral Maxillofacial Surgery, University of North Carolina, Chapel Hill, North Carolina, USA.
DDS, PhD
Centennial Fund Professor, Department of Prosthodontics, University of Iowa, Iowa City, Iowa, USA.
DDS
Craniofacial Clinical Research Center, University of Iowa, Iowa City, Iowa, USA.
DDS, PhD
Oral Health and Society Research Unit, Faculty of Dentistry, McGill University, Montreal, Canada.
DDS, MS
Director, Division of Restorative Dentistry, McGill University, Montreal, Canada.
DDS, MS
PerioHealth Professionals, Houston, Texas, USA.
DDS
PerioHealth Professionals, Houston, Texas, USA.
Purpose: The implant-abutment interface may affect peri-implant mucosal architecture, and influence health and esthetics. The goal of this 1-year follow-up report of a 5-year clinical investigation was to examine the peri-implant mucosal tissue responses to different implant-abutment interface designs.
Materials and Methods: Subjects requiring an anterior maxillary implant were recruited. Tooth extractions, with or without preservation or ridge augmentation procedures, were performed as required. After 5 months of healing, one of three different implant-abutment combinations (conical interface [CI] n = 48); flat-to-flat interface [FI] n = 49); or platform switch interface [PS] n = 44) was placed and provisionalized. Twelve weeks later, permanent crowns were placed and data gathered throughout the first year. Peri-implant mucosal architecture and bone levels were evaluated clinically, photographically, and radiographically.
Results: At 1 year, seven FI and six PS implants failed and two FI and two PS implant participants were lost to follow-up, resulting in survival rates of 100% (CI), 85.7% (FI), and 86.4% (PS) (90.8% overall). Marginal bone level changes were –0.22 mm (CI, P < .05), –1.2 mm (FI, P < .05), and –1.32 mm (PS, P < .05) after 1 year. Marginal bone level stability (≤ 0.5-mm bone loss or gain) was recorded for 87% (CI), 8% (FI), and 27% (PS) of implants. Measurement of midbuccal mucosal zenith and papilla positions revealed no change in the mucosal positions and 0.2 to 0.3 mm of gain in papilla dimensions in all groups.
Conclusion: Significant differences in marginal bone loss were observed among the three implant-abutment interfaces. At 1 year follow-up, changes in the buccal mucosal zenith position or papilla dimensions were not discernable. A continued longitudinal evaluation of peri-implant bone and mucosal changes around these different interfaces is ongoing.