Search results for "hydroxyapatite"

Home Oral Care Domiciliary Protocol for the Management of Dental Erosion in Rugby Players: A Randomized Clinical Trial

2022

People performing regular physical activity are at high risk of dental erosion especially in cases of high sport drinks intake. Biomimetic hydroxyapatite-based oral hygiene products, like toothpastes and mouthwashes, have been investigated in recent years for their remineralizing activity on the teeth. The aim of the present study was to evaluate the efficacy of two different oral hygiene protocols, respectively consisting of the combination of a hydroxyapatite-based toothpaste plus mouthwash (Trial group) or toothpaste alone (Control Group). At baseline (T0), as well as at 15 days (T1), 30 days (T2) and 90 days (T3), the following clinical indexes were assessed: Basic Erosive Wear Examinat…

CaP-Bioglass composite coating by galvanic deposition

Orthopedic devices are increasingly used in our life to improve the health of patients after bone fractures due to accidents, aging, or sports injuries. Metallic materials (i.e. stainless steel, titanium alloys chromium alloys) are widely employed to fabricate prostheses, screws, and osteosynthesis plates. Although metals could be good mechanical properties like human bone, corrosion phenomena could occur, causing in the worst cases the failure of orthopedic implants. In addition, metal ions released around periprosthetic tissues could arise allergenic and cancerogenic effects. Nowadays, the research was focused on coating science to deal with these issues. In particular, the development of…

Behavior of Calcium Phosphate–Chitosan–Collagen Composite Coating on AISI 304 for Orthopedic Applications

2022

Calcium phosphate/chitosan/collagen composite coating on AISI 304 stainless steel was investigated. Coatings were realized by galvanic coupling that occurs without an external power supply because it begins with the coupling between two metals with different standard electrochemical potentials. The process consists of the co-deposition of the three components with the calcium phosphate crystals incorporated into the polymeric composite of chitosan and collagen. Physical-chemical characterizations of the samples were executed to evaluate morphology and chemical composition. Morphological analyses have shown that the surface of the stainless steel is covered by the deposit, which has a very r…

Characterization of Rabbit Mesenchymal Cell Attachment on Calcium Phosphate Surface

2014

In the current study, the effect of three different treated surfaces of hydroxyapatite and β-tricalcium phosphate on mesenchymal cell attachment has been investigated. Calcium phosphate powders have been synthesized, uniaxially pressed, polished and sintered. Mesenchymal cells have been seeded onto unpolished, polished and polished-thermally etched ceramic samples. The ceramic samples have been characterized by XRD, FTIR and SEM. Results have shown that the best cell attachment and morphology are on the unpolished surface indicating that relatively rough surface is better for cell application.

Formation of nanosized strontium substituted hydroxyapatites

2012

Incorporation of specific elements into calcium phosphates offers the combination of a bioactive material and a therapeutic effect. This is important for improving the integration of implants as well as treating medical conditions. Strontium is a suitable candidate and displays the ability to stimulate bone growth and reducing bone resorption. This study investigated the formation of strontium carbonated hydroxyapatite nanoparticles from an amorphous phase. Crystallization of carbonated hydroxyapatite occurred at 585 o C, but samples with an intended 25% and 75% replacement of calcium with strontium crystallized at 624 o C. Heat treatment at the crystallization temperature revealed that str…

Hydrothermally Synthesized Strontium Peroxyapatite

2015

The current research focuses on peroxide ion incorporation in the structure of strontium hydroxyapatite (SrHAp) by exposure to H2O2 ina closed hydrothermal vessel under mild conditions at 130 to 170 °C. Peroxide enriched strontium apatite (SrPerAp) was characterized for structure by X-Ray diffraction, for peroxide content- by permanganometric titration and then viewed by SEM. This study continued from previous work that used 30%H2O2 and showed a higher included peroxide content after processing with 50% H2O2 at 130 °C 70% of the theoretical peroxide content in apatitic channels of strontium apatite. This is the highest peroxide content incorporated to date and employs a lower temperature th…

PLLA Scaffold via TIPS for Bone Tissue Engineering

2016

Tissue engineering offers a promising new approach to repair bone fractures, fractures that do not heal, and fractures due to bone tumors. In this work, two different approaches were tested in order to obtain Poly-L- Lactic Acid (PLLA) porous scaffolds via Thermally Induced Phase Separation (TIPS) for bone tissue engineering application. First, the possibility to produce a composite material, by incorporating Hydroxyapatite (HA) particles in a Poly-L-lactic acid (PLLA) matrix was investigated. Two PLLA/HA weight ratios (70/30 and 50/50) were tested. The results showed that the presence of HA does not influence the phase separation process, i.e. the composite scaffolds microstructure is simi…

Development of Phosphatized Calcium Carbonate Biominerals as Bioactive Bone Graft Substitute Materials, Part I: Incorporation of Magnesium and Stront…

2018

Synthetic materials based on calcium phosphate (CaP) are frequently used as bone graft substitutes when natural bone grafts are not available or not suitable. Chemical similarity to bone guarantees the biocompatibility of synthetic CaP materials, whereas macroporosity enables their integration into the natural bone tissue. To restore optimum mechanical performance after the grafting procedure, gradual resorption of CaP implants and simultaneous replacement by natural bone is desirable. Mg and Sr ions released from implants support osteointegration by stimulating bone formation. Furthermore, Sr ions counteract osteoporotic bone loss and reduce the probability of related fractures. The presen…

The use of calcined paper mill sludge as a chemical precipitant in the simultaneous removal of ammonium and phosphate : paper mill waste recycling an…

2020

Currently, recycling and re-use of materials is extremely important due to the diminishing of natural resources. The objective of the European Union’s circular economy strategy is to increase recycling and the use of industrial waste materials and side streams as secondary raw materials. In this study, a chemical precipitation method to simultaneously remove ammonium nitrogen and phosphate from the liquid phase of anaerobic digestate using calcined paper mill sludge was studied. Papermill sludge is a waste material that forms in the paper-making process. In addition, commercial calcium oxide (CaO) was used as a reference precipitant. The suitability of the formed precipitate’s composition f…

The influence of ossein-hydroxyapatite compound ('Ossopan') on the healing of a bone defect.

1986

A study was undertaken in 60 adult rabbits in order to determine the effects of ossein-hydroxyapatite compound on bone healing. Standardized bony defects were produced in the distal femoral epiphyses, after which animals were randomized into four equal groups. An untreated group served as a control. One group received ossein-hydroxyapatite compound, 830 mg per day, a second group received bone mineral (ossein-hydroxyapatite compound reduced to ash, to remove organic constituents), 510 mg per day, and a third group received calcium carbonate, 650 mg per day. A series of fluorescent vital markers was administered to the animals from the 7th to the 32nd day after production of the defect. A th…