Prospective cohort study to evaluate narrow diameter implants for the restoration of a missing maxillary lateral incisor in patients with a cleft palate: Five-year results.

STATEMENT OF PROBLEM: The maxillary lateral incisor is often congenitally missing in patients with a cleft palate. The congenital cleft presents the practitioner with challenges including quantity and quality of bone, a surgically managed cleft correction, and limited clinical space.

PURPOSE: The purpose of this investigation was to calculate the 5-year success and survival rate of narrow-diameter implants used to restore a missing lateral incisor in patients with a cleft palate.

MATERIAL AND

METHODS

Fourteen study participants with a cleft palate and a missing maxillary lateral incisor were enrolled based on established criteria. Seventeen narrow-diameter implants (AstraTech OsseoSpeed 3.0S and OsseoSpeed TX 3.5 mm) were placed using a 2-stage protocol and restored with a custom titanium abutment and a cement-retained crown. Clinical and radiographic examinations were performed annually for 5 years. Four probe depth measurements were measured and evaluated using an analysis of covariance (ANCOVA) with Tukey-Kramer multiple comparisons tests. Radiographic marginal bone loss was measured annually using a digital subtraction technique and evaluated with ANCOVA, and the least square mean was derived. The restoration was evaluated using Pink (PES) and White (WES) Esthetic scores.

RESULTS

Regarding probing depth measurements, a significant variance was found between the 4 locations (P<.001), and a linear effect of year was also found (P=.005). The multiple comparisons tests showed the mean buccal probe depth was lower compared with the mean at each of the other 3 locations (P≤.039) from baseline to 5-year follow-up. The least square mean ±standard deviation of the marginal bone loss over the 5-year entire study was 0.55 ±0.088 mm. Regarding prosthesis evaluation, the mean score for PES was 6.15 and 6.63 for the WES with a maximum score of 10. The level for clinical acceptance was set at a total score of 6. To meet the criteria for success over the 5-year period, no more than 2.3 mm of total bone loss was acceptable. The number of implants that met the criteria for success at 5 years was 92%. Regarding survival, the number of implants still in place, functional, and asymptomatic at 5 years was 100%.

CONCLUSIONS

Based on the findings, the peri-implant soft tissue probe depths exhibited significant change during the 5-year investigation. Regarding esthetic outcomes, single tooth NDI for replacing a lateral incisor in the cleft patient is a clinically acceptable treatment. Narrow-diameter implants may be a reliable treatment for replacing a missing lateral incisor in patients with a cleft at 5-year follow-up with an implant survival rate of 100% and a success rate of 92%.