A study of two xenograft particle sizes in bone healing and angiogenesis in sinus lift procedure

15975 POSTER WITH ORAL PRESENTATION CLINICAL RESEARCH – SURGERY

Background

A xenograft material is widely used in bone augmentation including sinus lift procedure. Commercially, Bio-Oss®, xenograft, provides small particle size (0.25–1 mm) and large particle size (1–2 mm). However, the previous data remain unclear whether bone formation related the different particle size of xenograft in radiographic and histomorphometric study. No report demonstrates the effect of different grafting particle and new vascular in growth after sinus augmentation procedure.

Aim/Hypothesis

To compare bone healing and neovascularization using large or small particle of xenografts in maxillary sinus augmentation procedure.

Material and Methods

Randomized, double blind, clinical trial was performed in thirty-two patients. Candidates were divided into 2 groups randomly, group I; nineteen patients were subjected to sinus lift procedure using Geistlich Bio-Oss® small particle grafting (0.25–1 mm) and group II with thirteen patients using Bio-Oss® large particle grafting (1–2 mm). After sinus augmentation for 6 months, bone specimens were harvested before dental implant placement procedure. Newly formed bone pattern, residual particle and fibrous formation in histomorphometric study related with micro CT analysis of two different particle sizes were determined using haemotoxylin and eosin (H&E) staining. Neovascularization was examined using VEGF expression.

Results

Micro CT analysis showed that grafted with coarse particle of xenograft in sinus lift procedure promoted 36.36% more newly formed bone compared to fine particle of xenograft with statistically significance at P-value = 0.03. Histological data showed higher newly formed bone area (21.8% in large particle and 13% in small particle group) with more residual particle of xenograft in the large particle group. On the other hand, abundant fibrous tissue was identified in small particle group (75.47%) compared to small portion of fibrous tissue in large particle group (38.44%). In addition, large particle revealed higher VEGF expression in grafted specimen.

Conclusion and Clinical Implications

The data suggested that large particle size (1–2 mm) of xenograft promotes more newly formed and neovascularization compared to small particle (0.25–1 mm). Large xenograft particle is recommended for sinus lift procedure.