Lateral bone augmentation with newly developed β-tricalcium phosphate block: an experimental study in the rabbit mandible.

OBJECTIVE

To evaluate the biological effects of newly developed β-tricalcium phosphate (β-TCP) to improve lateral bone augmentation.

MATERIAL AND METHODS

Test samples (rod-shaped [RS]-blocks) were prepared through hydrothermal processing α-TCPs. As controls, commercially available β-TCPs (C-blocks; Osferion) were used. The blocks were placed onto the rabbit mandibles (n=5/group, mean: 4 kg). Samples were retrieved after 6, 12 and 24 weeks. Thereafter, the sections were evaluated for histological and histomorphometric analyses. The parameters set were: BV/TV (%): [(area of newly formed bone; area-NFB)/(whole measured area; WA)] × 100, BV+Imp.V/TV (%): [(area-NFB+area of remaining β-TCP block)/WA] × 100, N.Oc/I.Pm: (osteoclast number)/(entire β-TCP block perimeter; 100 mm).

RESULTS

BV/TV of the C-blocks (10.71 ± 3.39%) was significantly higher than the RS-blocks (3.5 ± 3.52%, P<0.05) at 6 weeks. At 24 weeks, the RS-blocks (23.66 ± 2.7%) showed significantly higher values than the C-blocks (13.23 ± 2.65%, P<0.001). The BV+Imp.V/TV of the RS-blocks was significantly higher than that of the C-block group (29.61 ± 5.84% and 19.13 ± 3.14%), maintaining high values between 6 and 24 weeks (44.16 ± 5.19% and 50.88 ± 4%, P<0.001). The N.Oc/I.Pm values were significantly greater in the RS-block group than in the C-block group throughout the observation period (P<0.05).

CONCLUSIONS

The newly developed β-TCP blocks presented subsequent replacement by newly formed bone, in conjunction with maintaining the external morphology.