Antibacterial effect of morphous (poly-crystalline) and amorphous (glass) nano-bioactive glass 45S5 on Streptococcus mutans‏

Objective: Bioactive glass 45S5 is a surface reactive glass-ceramic biomaterial, developed in 1969. BAG 45S5 with particle size of 20-60 nm has the ability of bone regeneration, broad spectrum antibacterial effect, repairs and replaces diseased or damaged bone. The aim of this study was to evaluate the antibacterial activity and determine MIC and MBC values of nano-BAG45S5 on Streptococcus mutans. Methods: In this study the in vitro Antibacterial activity of polycrystalline and glass forms of nanoBAG 45S5 was evaluated. Bacterial susceptibility to test materials was examined by antibiogram test. Afterwards MIC and MBC assays were conducted via broth dilution, disc diffusion and colony count methods. Results: Despite amorphous nano-BAG 45S5, poly-crystalline form had antibiogram negative test result. In broth dilution test, the optical absorbance of test dilution of 50mcg/ml and higher concentrations were equal to negative control’s optical absorbance and their inhibitory zone diameter were measured 10.0mm in disc diffusion test. No colony was observed on the culture media of test dilution of 200mcg/ml and higher concentrations. Conclusion: Streptococcus mutans (ATCC 35668) is not susceptible to poly-crystalline nanoBAG45S5. Amorphous nano-BAG45S5 is bacteriostatic against Streptococcus mutans. MIC and MBC values for amorphous nano-BAG45S5 were 50 ppm and 200 ppm, respectively

Antibacterial effect of morphous (poly-crystalline) and amorphous (glass) nano-bioactive glass 45S5 on Streptococcus mutans

Objective: Bioactive glass 45S5 is a surface reactive glass-ceramic biomaterial, developed in 1969. BAG 45S5 with particle size of 20-60 nm has the ability of bone regeneration, broad spectrum antibacterial effect, repairs and replaces diseased or damaged bone. The aim of this study was to evaluate the antibacterial activity and determine MIC and MBC values of nano-BAG45S5 on Streptococcus mutans.Methods: In this study the in vitro Antibacterial activity of polycrystalline and glass forms of nano- BAG 45S5 was evaluated. Bacterial susceptibility to test materials was examined by antibiogram test. Afterwards MIC and MBC assays were conducted via broth dilution, disc diffusion and colony count methods.Results: Despite amorphous nano-BAG 45S5, poly-crystalline form had antibiogram negative test result. In broth dilution test, the optical absorbance of test dilution of 50mcg/ml and higher concentrations were equal to negative control’s optical absorbance and their inhibitory zone diameter were measured 10.0mm in disc diffusion test. No colony was observed on the culture media of test dilution of 200mcg/ml and higher concentrations.Conclusion: Streptococcus mutans (ATCC 35668) is not susceptible to poly-crystalline nano- BAG45S5. Amorphous nano-BAG45S5 is bacteriostatic against Streptococcus mutans. MIC and MBC values for amorphous nano-BAG45S5 were 50 ppm and 200 ppm, respectively

Efficacy of the Biomaterials 3 wt%-nanostrontium-hydroxyapatite-enhanced Calcium Phosphate Cement (nanoSr-CPC) and nanoSr-CPC-incorporated Simvastatin-loaded Poly(lactic-co-glycolic-acid) Microspheres in Osteogenesis Improvement

Aims The purpose of this multi-phase explorative in vivo animal/surgical and in vitro multi-test experimental study was to (1) create a 3 wt%-nanostrontium hydroxyapatite-enhanced calcium phosphate cement (Sr-HA/CPC) for increasing bone formation and (2) creating a simvastatin-loaded poly(lactic-co-glycolic acid) (SIM-loaded PLGA) microspheres plus CPC composite (SIM-loaded PLGA + nanostrontium-CPC). The third goal was the extensive assessment of multiple in vitro and in vivo characteristics of the above experimental explorative products in vitro and in vivo (animal and surgical studies). Methods and results pertaining to Sr-HA/CPC Physical and chemical properties of the prepared Sr-HA/CPC were evaluated. MTT assay and alkaline phosphatase activities, and radiological and histological examinations of Sr-HA/CPC, CPC and negative control were compared. X-ray diffraction (XRD) indicated that crystallinity of the prepared cement increased by increasing the powder-to-liquid ratio. Incorporation of Sr-HA into CPC increased MTT assay (biocompatibility) and ALP activity (P \u3c 0.05). Histomorphometry showed greater bone formation after 4 weeks, after implantation of Sr-HA/CPC in 10 rats compared to implantations of CPC or empty defects in the same rats (n = 30, ANOVA P \u3c 0.05). Methods and results pertaining to SIM-loaded PLGA microspheres + nanostrontium-CPC composite After SEM assessment, the produced composite of microspheres and enhanced CPC were implanted for 8 weeks in 10 rabbits, along with positive and negative controls, enhanced CPC, and enhanced CPC plus SIM (n = 50). In the control group, only a small amount of bone had been regenerated (localized at the boundary of the defect); whereas, other groups showed new bone formation within and around the materials. A significant difference was found in the osteogenesis induced by the groups sham control (16.96 ± 1.01), bone materials (32.28 ± 4.03), nanostrontium-CPC (24.84 ± 2.6), nanostrontium-CPC-simvastatin (40.12 ± 3.29), and SIM-loaded PLGA + nanostrontium-CPC (44.8 ± 6.45) (ANOVA P \u3c 0.001). All the pairwise comparisons were significant (Tukey P \u3c 0.01), except that of nanostrontium-CPC-simvastatin and SIM-loaded PLGA + nanostrontium-CPC. This confirmed the efficacy of the SIM-loaded PLGA + nanostrontium-CPC composite, and its superiority over all materials except SIM-containing nanostrontium-CPC

Giant sialoliths of Wharton duct: Report of two rare cases and review of literature

Sialolithiasis is a common disease of the major salivary glands, characterized by the obstruction of a salivary gland or its excretory duct due to the formation of calcareous concretions. Sialoliths usually measure from 1 mm to 15 mm have been reported in the literature. The submandibular gland and its duct appear to be the most susceptible sites for this disease. In this article, we report two unique cases, including a giant bilateral case, measuring 50 mm in length and 5 mm in width on the right side and one, 30 mm in length, and 5 mm in width on the left side; and another case, measuring 83 mm in length. The diagnostic and therapeutic approaches consisted of transocclusal radiography with the conservative transoral surgical technique in both cases. The follow-up showed the normal function of the relevant salivary glands. To the best of our knowledge and belief, similar cases have not been reported in the literature

Comparison of the human bone matrix gelatin (HBMG) with autogenous bone graft in reconstruction of the parietal bone defects in rat: a histological and radiographic study

Background and aims. Autogenous bone graft is commonly used for reconstruction of bone defects in routine surgical procedures. The complexity of producing bone grafts and their application has lead to the use of human bone matrix gelatin (HBMG). The present study was conducted to compare the efficacy of HBMG and autograft on the reconstruction of bone defects in rats.
 Materials and methods. In this cross-sectional, experimental study, two defects were put on left and right sides of parietal bone of rats. HBMG was placed randomly on defects of one side and autograft in the defects of the other side. All specimens were assessed and compared with each other according to histological and radiographic characteristics. Other assessments included amount and the rate of bone formation, inflammation signs, fibrosis tissue and cartilage formation and also radiographic characteristics of grafts, assessed by digital and film-based methods. Mann-Whitney U test was used for statistical analysis.
 Results. The results showed a reduction of inflammation and an increase in new bone formation in both groups in 7, 14, 28 and 60 days after surgery. Bone formation with HBMG on day 24 was more than autograft. However, there was no significant difference between the groups on day 60. Superiority of digital method to film-based method of imaging was also observed.
 Conclusion. Although HBMG has the same efficacy as autograft, the rate of bone reconstruction with HBMG is higher. HBMG also induces focal, rather than peripheral, bone construction in the defect

Eight-year follow-up of malignant fibrous histiocytoma (undifferentiated high-grade pleomorphic sarcoma) of the maxilla: case report and review of the literature

Malignant fibrous histiocytoma (MFH) is the most common soft tissue sarcoma of late adult life and may also arise as a primary tumor in bone. It is a rare condition that constitutes less than 1% of the malignant tumors of bone and commonly occurs in the mathaphysis of long bones of extremities such as the femur and tibia. The occurrence in the head and neck region is very rare. MFH of the jaws is a highly malignant tumor that recurs, metastasizes, and usually causes death despite aggressive surgical therapy. We present a case of MFH of maxilla with 8 years follow-up. The clinical, pathologic and radiographic features as well as the treatment of this case are discussed