Bone reconstruction in the oral and maxillofacial region presents particular challenges related to the development of biomaterials with osteoinductive properties and suitable physical characteristics ...for their surgical use in irregular bony defects. In this work, the preparation and bioactivity of chitosan-gelatin (ChG) hydrogel beads loaded with either bioactive glass nanoparticles (nBG) or mesoporous bioactive glass nanospheres (nMBG) were studied.
testing of the bionanocomposite beads was carried out in simulated body fluid, and through viability and osteogenic differentiation assays using dental pulp stem cells (DPSCs).
bone regenerative properties of the biomaterials were assessed using a rat femoral defect model and compared with a traditional maxillary allograft (Puros®). ChG hydrogel beads containing homogeneously distributed BG nanoparticles promoted rapid bone-like apatite mineralization and induced the osteogenic differentiation of DPSCs
. The bionanocomposite beads loaded with either nBG or nMBG also produced a greater bone tissue formation
as compared to Puros® after 8 weeks of implantation. The osteoinductivity capacity of the bionanocomposite hydrogel beads coupled with their physical properties make them promissory for the reconstruction of irregular and less accessible maxillary bone defects.
The topography and composition of dental implant surfaces directly impact mesenchymal cell adhesion, proliferation, and differentiation, crucial aspects of achieving osseointegration. However, cell ...adhesion to biomaterials is considered a key step that drives cell proliferation and differentiation. The aim of this study was to characterize characterize the topography and composition of commercial titanium dental implants manufactured with different surface treatments (two sandblasted/acid-etched (SLA) (INNO Implants, Busan, Republic of Korea; BioHorizons
, Oceanside, CA, USA) and two calcium phosphate (CaP) treated (Biounite
, Berazategui, Argentina; Zimmer Biomet, Inc., Warsaw, IN, USA)) and to investigate their influence on the process of cell adhesion in vitro. A smooth surface implant (Zimmer Biomet, Inc.) was used as a control. For that, high-resolution methodologies such as scanning electron microscopy (SEM), X-ray dispersive spectroscopy (EDX), laser scanning confocal microscopy (LSCM), and atomic force microscopy (AFM) were employed. Protein adsorption and retromolar gingival mesenchymal stem cells (GMSCs) adhesion to the implant surfaces were evaluated after 48 h. The adherent cells were examined by SEM and LSCM for morphologic and quantitative analyses. ANOVA and Tukey tests (
= 0.05) were employed to determine statistical significance. SEM revealed that INNO, BioHorizons
, and Zimmer implants have an irregular surface, whereas Biounite
has a regular topography consisting of an ordered pattern. EDX confirmed a calcium and phosphate layer on the Biounite
and Zimmer surfaces, and AFM exhibited different roughness parameters. Protein adsorption and cell adhesion were detected on all the implant surfaces studied. However, the Biounite
implant with CaP and regular topography showed the highest protein adsorption capacity and density of adherent GMSCs. Although the Zimmer implant also had a CaP treatment, protein and cell adhesion levels were lower than those observed with Biounite
. Our findings indicated that the surface regularity of the implants is a more determinant factor in the cell adhesion process than the CaP treatment. A regular, nanostructured, hydrophilic, and moderately rough topography generates a higher protein adsorption capacity and thus promotes more efficient cell adhesion.
Risk factors associated with tooth loss have been studied; however, the current status of the epidemiological profiles and the impact of the pandemic on the oral health of the elderly is still ...unknown. This study aims to determine the experience of caries and tooth loss among elderly Chilean citizens in five regions and to identify the risk factors associated with tooth loss. The sample includes 135 participants over 60 years old assessed during COVID-19 lockdown. Sociodemographic variables such as education and RSH (Social Registry of Households) were obtained through a teledentistry platform called TEGO. The history of chronic diseases such as diabetes, obesity, depression and dental caries reported by DMFT index scores were incorporated. The statistical analysis included Adjusted Odds Ratios (ORs) to assess risk factors associated with the lack of functional dentition. Multivariate hypothesis testing was used to compare the mean equality of DMFT and its components between regions (
-value < 0.05). Individuals with RSH ≤ 40% were at higher risk of having no functional dentition with OR 4.56 (95% CI: 1.71, 12.17). The only mean difference between regions was the filled tooth component. Tooth loss was associated with multidimensional lower income, where the elderly belonging to the 40% most vulnerable population had a higher prevalence of non-functional dentition. This study highlights the importance of implementing a National Oral Health Policy that focuses on oral health promotion and minimally invasive dentistry for the most vulnerable population.
Objectives. To develop and implement a “semi-presential” technology platform to support urgent and priority dental care for the elderly in the context of the COVID-19 pandemic among the Chilean ...population. Methods. A dental mobile clinic was implemented along with the development of a technological platform designed to support emergency and priority dental procedures, including teleconsultation with specialists. Under strict biosafety protocols, dental care was provided in five Chilean regions between February and May 2021. Sociodemographic, medical, and dental data were recorded. Results. A total of 135 patients over sixty years old, with a mean age of 72 years, were treated, 48 males and 87 females were attended between February and May 2021 in five different regions of Chile. 53.3% required immediate or urgent treatment, and 24.4% were derived to specialists from whom 60.6% needed immediate or urgent treatment. 74.3% of teleconsultations were derived to an oral pathology specialist. Conclusion. It was shown that a “semi-presential” technology platform implemented in a mobile dental clinic can help elderly people who are impeded to look for traditional dental assistance during a pandemic.
Inorganic-organic hybrid biomaterials have been proposed for bone tissue repair, with improved mechanical flexibility compared with scaffolds fabricated from bioceramics. However, obtaining hybrids ...with osteoinductive properties equivalent to those of bioceramics is still a challenge. In this work, we present for the first time the synthesis of a class II hybrid modified with bioactive glass nanoparticles (nBGs) with osteoinductive properties. The nanocomposite hybrids were produced by incorporating nBGs in situ into a polytetrahydrofuran (PTHF) and silica (SiO
) hybrid synthesis mixture using a combined sol-gel and cationic polymerization method. nBGs ~80 nm in size were synthesized using the sol-gel technique. The structure, composition, morphology, and mechanical properties of the resulting materials were characterized using ATR-FTIR,
Si MAS NMR, SEM-EDX, AFM, TGA, DSC, mechanical, and DMA testing. The in vitro bioactivity and degradability of the hybrids were assessed in simulated body fluid (SBF) and PBS, respectively. Cytocompatibility with mesenchymal stem cells was assessed using MTS and cell adhesion assays. Osteogenic differentiation was determined using the alkaline phosphatase activity (ALP), as well as the gene expression of Runx2 and Osterix markers. Hybrids loaded with 5, 10, and 15% of nBGs retained the mechanical flexibility of the PTHF-SiO
matrix and improved its ability to promote the formation of bone-like apatite in SBF. The nBGs did not impair cell viability, increased the ALP activity, and upregulated the expression of Runx2 and Osterix. These results demonstrate that nBGs are an effective osteoinductive nanoadditive for the production of class II hybrid materials with enhanced properties for bone tissue regeneration.
The aim of this study was to explore the preparation of porous nanocomposite scaffolds with simultaneous osteogenic – antibacterial properties by incorporating copper – doped bioactive glass ...nanoparticles into Poly (D,L-lactide-co-glycolide) lactide:glycolide. Bioactive glass nanoparticles were synthesized by using sol–gel technique from the SiO2 – P2O5 – CaO – Na2O – CuO system. Poly (D,L-lactide-co-glycolide) lactide:glycolide nanocomposite scaffolds with different nanoparticle contents were prepared by combined lyophilization/salt leaching. The in vitro bioactivity of the scaffolds was assessed in simulated body fluid, and cell viability and osteogenic differentiation assays were performed with stem cells. Antibacterial activity of the materials was assessed against Staphylococcus aureus. Copper – dopped bioactive glass nanoparticles particles with ∼70 nm in size and relatively crystalline structure were synthesized. Porous nanocomposite scaffolds prepared with the copper – doped nanoparticles are cytocompatible, promoted the mineralization of bone-like apatite in simulated body fluid, and stimulated the osteogenic differentiation of stem cells as judged by an increased activity the enzyme alkaline phosphatase. The antibacterial activity exhibited by the nanocomposite scaffolds was not statistically superior to that of the neat polymer scaffold. Development of greater antibacterial activity in these nanocomposites would requires further research primarily related to the synthesis of more amorphous and soluble copper – dopped bioactive glass nanoparticles.
