Use of biomaterials in the surgical regenerative treatment of peri-implantitis: systematic review

The aim of this study was to review the scientific literature regarding the effectiveness of different biomaterials in the regenerative treatment of peri-implantitis. A systematic literature search was performed in PubMed/Medline, Web of Science, Science Direct, Embase, and the Cochrane Collaboration Library. Studies on the use of biomaterials in the regenerative treatment of peri-implantitis were selected. The search strategy retrieved 253 articles. After selection, six articles met all inclusion criteria and were included in the present systematic review. The studies showed that an initial therapeutic approach consisting of plaque control and implant surface decontamination and subsequent surgery for biomaterial placement were essential for the successful regenerative treatment of peri-implantitis defects. Analysis of all biomaterials used in surgical regenerative treatment showed that bovine bone grafts provided superior outcomes in terms of new bone formation compared to autogenous grafts and nanocrystalline hydroxyapatite. It is important to note that porous titanium granules have emerged as a promising biomaterial for the regenerative treatment of peri-implantitis. In conclusion, biomaterials are promising for the treatment of peri-implant bone defects and the number of in silico biomaterials that can provide treatment of excellence to patients with this condition is expected to increase in the near future.

Synthesis and Characterization of a Biocompatible Bioactive Borate Glass

A typical bioactive borate glass of composition 5Na2O-30Ca-65B2O3(NCBO) was prepared by melt quenching method. The NCBO glass powder and solid glass fibers were found to slowly converted to nanocrystalline hydroxyapatite (or Ca10(PO4)6(OH)2) by soaking in (0.25M)K2HPO4(KDP) solution (with pH = 9.5 and Ca/P ratio ˜1.6 at 37°C) for about one month. We studied biocompatibility (cells adhesion and proliferation) of the NCBO glass by allowing adhesion and proliferation of human cord blood derived mesenchymal stem cells (CB-hMSCs) directly on the thin glass plate. The cells viability on glass surface was determined by MTT [3-(4,5-di-methylthiazol-2-yl)-2,5 diphenyl tetrazolium bromide] assay analysis. The NCBO glass exhibiting excellent biocompatibility might be suitable for in vivo tissue engineering applications.

Tetracalcium Phosphate/Monetite/Calcium Sulfate Hemihdrate Biocement Powder Mixtures Prepared by the One-Step Synthesis for Preparation of Nanocrystalline Hydroxyapatite Biocement-Properties and In Vitro Evaluation

A modified one-step process was used to prepare tetracalcium phosphate/monetite/calcium sulfate hemihydrate powder cement mixtures (CAS). The procedure allowed the formation of monetite and calcium sulfate hemihydrate (CSH) in the form of nanoparticles. It was hypothesized that the presence of nanoCSH in small amounts enhances the in vitro bioactivity of CAS cement in relation to osteogenic gene markers in mesenchymal stem cells (MSCs). The CAS powder mixtures with 15 and 5 wt.% CSH were prepared by milling powder tetracalcium phosphate in an ethanolic solution of both orthophosphoric and sulfuric acids. The CAS cements had short setting times (around 5 min). The fast setting of the cement samples after the addition of the liquid component (water solution of NaH2PO4) was due to the partial formation of calcium sulfate dihydrate and hydroxyapatite before soaking in SBF with a small change in the original phase composition in cement powder samples after milling. Nanocrystalline hydroxyapatite biocement was produced by soaking of cement samples after setting in simulated body fluid (SBF). The fast release of calcium ions from CAS5 cement, as well as a small rise in the pH of SBF during soaking, were demonstrated. After soaking in SBF for 7 days, the final product of the cement transformation was nanocrystalline hydroxyapatite. The compressive strength of the cement samples (up to 30 MPa) after soaking in simulated body fluid (SBF) was comparable to that of bone. Real time polymerase chain reaction (RT-PCR) analysis revealed statistically significant higher gene expressions of alkaline phosphatase (ALP), osteonectin (ON) and osteopontin (OP) in cells cultured for 14 days in CAS5 extract compared to CSH-free cement. The addition of a small amount of nanoCSH (5 wt.%) to the tetracalcium phosphate (TTCP)/monetite cement mixture significantly promoted the over expression of osteogenic markers in MSCs. The prepared CAS powder mixture with its enhanced bioactivity can be used for bone defect treatment and has good potential for bone healing.