Effect of Silicon food supplement on bone tissue healing: histomorphometric and EDS analysis in human

Abstract

Introduction: Few clinical trials reported beneficial impact of Si on bone metabolism, but no study on alveolar bone healing has been published [1]. Aim of this study was to assess if daily supplementation of Si: i) increases amount of Si within the newly formed alveolar bone, ii) induces histomorphological changes of newly formed alveolar bone. Materials and Meth- ods. 20 systemically healthy individuals requiring premolar tooth extraction were included and immediately after the tooth extraction were randomly assigned to group A (1 tablet/day for 4 months containing Si) or to group B (1 tablet/day for 4 months containing placebo). At 4 months post-op, a bone core biopsy was harvested from each healed site, processed for ground sections and stained. For morphological and histomorphometric analyses, slides were observed using a light microscope equipped with a digital camera and photos were acquired at mag- nification of 100X. Stereological analysis was done to obtain the proportions of the specimen occupied by every regenerated tissue: lamellar bone, woven bone, osteoid, medullary spaces. Sections were observed using a BSE-SEM system without additional fixation and previous coat- ing of carbon film to assess level of mineralization of regenerated tissue. Slides were observed at energy dispersive spectroscopy to assess levels of silicon in regenerated tissue (% Mass). In both groups, mean and standard deviation were calculated for clinical data, percentage of connective tissue, osteoid and mature bone, % Mass of Si. Inferential statistics was also done.Results. Two patients withdrew from the study. Bone sample harvesting was done on 8 patients of group A and 10 patients of group B. The mean Si content in samples of group A was 0.9% and in samples of group B was 0.2% (no significant differences). Si concentration appeared higher in medullary spaces than in the bone. Si concentration in the mature bone appeared low- er than in the bone in the phase of mineralization and in the medullary spaces. Volume fraction of lamellar bone was significantly higher in group A than in group B, and volume fraction of osteoid matrix was significantly lower in group A than in group B (p<0.05, Wilcoxon rank sum test). Newly formed blood vessels were 9.75% ± 1.56 for group A and 9.53% ± 3.24 for group B (no significant difference). Conclusions. Supplementation seems to increase Si levels in healing bone tissue and seems to accelerate maturation process of mineralized connective tissue.