The Effectiveness of Hyaluronic Acid on Prefabricated CAD CAM Bone Blocks for Ridge Augmentation: A Split Mouth Study

Alveolar ridge augmentation has been one of the most accepted treatments for restoring bone volume. Various products are available in particle forms, which have limitations, especially related to controlling the expected volume gain. A prefabricated computer-aided design and computer-aided manufacturing (CAD-CAM) allogenic bone block could provide a good alternative.

A split-mouth randomized clinical trial included 10 patients with the bilateral posterior atrophic mandible (20 sides), who were randomly assigned to two groups with an allocation ratio of 1:1. Group I: the ridge was augmented using prefabricated CAD-CAM allogenic bone block hydrated using hyaluronic acid, and group II was hydrated using saline. Blinding was limited to the patients and the investigator responsible for data analysis (double blinding). Six months after grafting surgery, a core biopsy was taken for histological analysis, and implants were inserted into the augmented ridge. The amount of bone gain was evaluated radiographically using CBCT.

All ridges in both groups revealed a successful bone gain in CBCT. However, the mean bone gain in group I (3.975 ± 0.31) was significantly higher than in group II (2.497 ± 0.66). Histologically, both groups showed osteointegration and new bone formation, with group I being superior. VEGF, OPN, and Cox 2 expressions were more intense in group I than in group II. The histomorphometric analysis revealed that group I had a considerably higher surface area of new bone formation than group II (p-value < 0.001). Immunohistochemical staining for VEGF revealed a significant difference between groups I (15.04 ± 0.47) and II (11.41 ± 0.54).

Within the limitations of this study, the addition of HA to prefabricated CAD-CAM allogenic block enhanced its osteogenic properties and guaranteed adequate integration of the graft for implant insertion.

This clinical trial was not registered before the participants' recruitment and randomization (https://clinicaltrials.gov/study/NCT06395818).