Physicochemical characterization of six commercial hydroxyapatites for medical-dental applicatons as bone graft

Abstract

he aim of this work was to characterize six hydroxyapatites in granular form for applications in medicine and dentistry as bone graft and to compare with manufacturers´ specification. These samples were produced by four different manufacturers, and all of them are easily available in the Brazilian market. Physicochemical characterization was carried out by using electron microscopy (SEM), X-ray diffraction (XRD), infrared spectroscopy (FTIR) and surface area (BET) measurements. The results show that just one hydroxyapatite sample exhibited characterisitics in perfect agreement with the manufacturers' specifications. The studied parameters, namely crystallinity, surface area and composition may be used to estimate hydroxyapatite's biodegradability and as a criterion for quality control. Uniterms: Hydroxyapatite; Calcium phosphate; Bone graft; Physicochemical characterization. objetivo desse trabalho foi caracterizar seis hidroxiapatitas granulares para aplicação em área médico-odontológica como material de enxerto. Estes materiais foram produzidos por quatro diferentes fabricantes e são todos facilmente disponíveis no mercado brasileiro. A caracterização físico-química foi realizada por meio de microscopia eletrônica de varredura, difração de raios-X, espectroscopia de infravermelho e área superficial específica (BET). Os resultados mostraram que apenas um dos produtos teve a caracterização perfeitamente de acordo com a especificação do fabricante. Os parâmetros de cristalinidade, área superficial e composição podem ser usados para estimar a biodegradabilidade da hidroxiapatita e como critério de controle de qualidade desses materiais. Unitermos: Hidroxiapatita; Fosfato de cálcio; Enxerto ósseo; Caracterização físico-química.

Implant Stability of Biological Hydroxyapatites Used in Dentistry

“…Different physicochemical conditions selectively modulate the host organism's tissue response [15]. Some authors have reported the same observations in reaction to the microscopic structure in commercial products subjected to thermal deproteinization processes [16,17]. Sintering temperature is considered an important factor that might alter the HA´s characteristics [18].…”

SEM-EDX Study of the Degradation Process of Two Xenograft Materials Used in Sinus Lift Procedures

“…This discrepancy may affect the material's performance [20]. Many reviews have discussed a number of biomaterials and their manufacturing processes for biodegradable scaffold fabrication, but very little work has been done to obtain biomaterials with patient-specific degradation rates [21][22][23][24]. One of the future challenges in bone tissue engineering is to design and manufacture biodegradable scaffolds with a homogeneous growth rate over their entire volume using pore size gradients or specific distributions.…”

“…Xenografts are usually of bovine or porcine origin, and are constituted by HA similarly to human bone [Ca10 (PO4)6(OH) 2]. This type of graft can be deproteinized and/or demineralized under different physicochemical conditions, which selectively modulate the tissue response of the host organism [22].…”

Surgical Elevation of Bilateral Maxillary Sinus Floor with a Combination of Autogenous Bone and Lyophilized Bovine Bone

“…[1][2][3][4] Due to certain exceptional situations that can occur in the oral cavity, such as periodontitis, loss of teeth, traumatic extractions, cysts, tumors or trauma aggravated over time, the surgeon does not always find the most favorable conditions to accomplish rehabilitative treatments involving the installation of dental implants. [5][6][7][8][9][10] To recover the ideal size dimensions lost by alveolar bone that has suffered resorption, particularly in edentulous patients, it is necessary to increase the height and width of the bone to accommodate implants of the appropriate size with an axial angle that adequately allows for future prosthesis. 2,8 Two dimensions must be taken into consideration regarding the material needed to anchor the implantation of these structures: height, which determines the length of the implants to be installed and, thickness which dictates the size of their turns and, consequently, their platform.…”

“…2 According to the literature, biomaterials can be defined as a substance or combination of two or more pharmacologically inert substances, whether natural or synthetic, which are used to improve, enhance or fully or partially replace tissues and organs. 7,21 Therefore, the ideal bone substitute should maintain mechanical stability and tissue volume during the early stages of healing and subsequently be supplied with new bone by osteoclast activity followed by the deposition of an osteoid matrix mediated by osteoblasts and mineralization. 22 In the case described here, autogenous bone grafting was chosen in combination with lyophilized bovine bone.…”