Treatment concepts of horizontally deficient ridges-A retrospective study comparing narrow-diameter implants in pristine bone with standard-diameter implants in augmented bone.

OBJECTIVES To compare clinical and radiological outcomes of narrow-diameter implants (NDI) placed in pristine bone to standard-diameter implants placed in combination with horizontal bone augmentation procedures (SDI+A) for horizontally deficient alveolar ridges. MATERIAL AND METHODS For this retrospective study, the outcome of 597 NDI (∅ 3.3 mm, 272 patients), inserted in pristine bone, were compared with 180 SDI (∅ 4.1 mm, 83 patients), inserted in combination with horizontal augmentation procedures. Oral health-related quality of life was assessed in patients available for recall. RESULTS After a mean follow-up of 37.6 ± 40 months for the NDI and of 42.4 ± 49 months for the SDI+A, survival rates were 96.1% for NDI and 95.6% for SDI+A. Cumulative 5-year and 10-year implant survival rates were 94.3% and 92.2% for the NDI group and 97.0% and 88.3% for the SDI+A group, indicating no significant difference (p = .89). According to the criteria of Buser et al., an implant success rate of 84.3% was obtained for the NDI and an implant success rate of 81.3% for the SDI+A (p = .79). Regarding oral health-related quality of life, a similar and high patient satisfaction could be observed in both groups. CONCLUSIONS NDI without augmentation procedures showed a similar clinical outcome as SDI in combination with augmentation procedures after a follow-up of more than 3 years. Therefore, NDI might be a reasonable alternative in cases of horizontal bone atrophy (no clinical trial registration as patient inclusion started 2003).