Does Graft Particle Type and Size Affect Ridge Dimensional Changes After Alveolar Ridge Split Procedure?

Abstract

The absence of an adequate volume of bone at implant sites requires augmentation procedures before the placement of implants. The aim of the present study was to assess the ridge width gain with the use of allografts and biphasic β-tricalcium phosphate with hydroxyapatite (alloplast) in ridge split procedures, when each were used in small (0.25 to 1mm) and large (1 to 2mm) particle sizes. A randomized controlled trial of 23 subjects with severe atrophy of the mandible in the horizontal dimension was conducted in a private institute. The patients underwent placement of 49 dental implants after a staged ridge split procedure. The patients were randomly allocated to alloplast and allograft groups (predictor variable). In each group, the patients were randomly assigned to either small graft particle or large graft particle size (predictor variable). The gain in ridge width (outcome variable) was assessed before implant placement. A 2-way analysis of variance test and the Student unpaired t test were used for evaluation of the ridge width gain between the allograft and alloplast groups (predictor variable). Differences were considered significant if P values were < .05. The sample included 23 patients (14 men and 9 women). The patients were randomly allocated to the alloplast (n=11) or allograft (n=12) group before the ridge split procedure. In each group, they were assigned to a small graft particle or large graft particle size (alloplast group, small particle in 5 and large particle size in 6 patients; allograft group, small particle in 6 and large particle size in 6). A statistically significant difference was observed between the 2 graft types. The average ridge width gain was significantly greater in the alloplast group (large, 4.40±0.24mm; small, 3.52±0.59mm) than in the allograft group (large, 3.82±0.19mm; small, 2.57±0.16mm). For both graft types (alloplast and allograft), the large particle size graft resulted in a greater ridge width gain compared with the small particle size graft (P<.05). Within the limitations of the present study, we suggest the use of large particle alloplast as the graft material of choice for staged ridge split procedures in the posterior mandible.