Cortical Block Grafting Successfully Augments Alveolar Cleft Sites for Dental Implant Placement

Abstract

BackgroundSupplemental bone grafting is regularly required before dental implant placement in patients with cleft lip and palate (CLP). PurposeThe study purpose was to measure and compare implant osseointegration and changes in graft dimensions following lateral incisor onlay cortical bone grafting in CLP and non-CLP patients. Study design, setting, sampleRetrospective cohort study composed of patients who presented to Boston Children’s Hospital and underwent autogenous onlay cortical block bone grafting at lateral incisor sites from 2015 through 2023. Patients were excluded if the cone beam computed tomography (CBCT) quality was insufficient for accurate measurements. Predictor variableThe predictor variable was CLP status coded as CLP or non-CLP. Main outcome variableThe primary outcome variable was successful implant osseointegration confirmed by a torque of 35 N/cm or more after 3 months of implant healing. Secondary outcomes were change in bone width between pre- and post-operative CBCT scans at lateral incisor sites and the need for additional bone augmentation prior to or during implant placement. CovariatesCovariates were age, sex, cleft location, and time from bone graft to postoperative CBCT and implant placement. AnalysesData analyses were performed using T-tests, Fisher’s Exact Tests, Mann-Whitney U Tests, and Pearson’s correlation. P<0.05 was considered statistically significant. ResultsA total of 22 subjects (16 with CLP) were evaluated. The mean age at the time of graft was 19.3 ± 2.4 years with 52.6% males. Implants osseointegrated at 20 of 22 lateral incisor sites (one CLP failure, one non-CLP failure). There was significant change in bone width after grafting for patients with CLP (p<0.001). Patients with CLP experienced a 3.32 (± 1.80) mm and 2.99 (± 1.61) mm increase in bone width at two different levels. Patients with CLP achieved greater boney changes near the alveolar crest than non-cleft patients (p=0.008) but the change was not significantly different more apically (p=0.86). One subject with CLP required additional grafting during implant placement. Conclusions and RelevanceCortical block onlay bone grafting is a predictable technique to augment lateral incisor sites in patients with cleft lip and palate for placement of a dental implant.