Māra pilmane

New Biphasic Calcium Phosphate in Orthopedic Surgery: First Clinical Results

This study evaluated first results of biphasic phosphate (BCP) ceramic granules with hydroxyapatite (HAp)/ β-tricalcium phosphate (TCP) ratio of 90/10 as bone substitute for reconstruction of the bone defects in orthopedic surgery, such as fracture and fracture non union treatment, primary and revision arthroplasty and chronic osteomyelitis. We evaluated twelve clinical cases of patients who had undergone surgeries with BCP implantation. Follow up period range from 2 to 8 months, on average 4.5 months. The classification of results was based on clinical and radiographic assessments. The size of defects ranged from 32 cm to 1 cm, average 6.42 cm, median 3 cm. The best results were obtained from patients after elective orthopedic procedures and patients with bone defects less than 3 cm.

Autologous Fibrin Mixed with Biphasic Calcium Phosphate Bioceramic Granules Activates Encapsulation in Soft Tissue Environment

The physical, chemical and biological properties of both biphasic calcium phosphate (BCP) bioceramics and fibrin scaffolds may be cumulated for preparing advanced bone substitutes. Aim of experimental study was to evaluate histological response on implantation of synthetic biphasic HAp/TCP bioceramic granules mixed with autologous plasma derived fibrin scaffold in subcutaneous tissue of rabbits.

Time-dependent cytokine expression in bone of experimental animals after hydroxyapatite (Hap) implantation

Proinflammatory cytokines mediate bone loss around the implants in patients with peri-implant disease. However, there is no complete data about the expression of cytokines into the bone around the implants. The aim of this work was to investigate the distribution and appearance of inflammatory cytokines and anti-inflammatory proteins in the bone of jaw of experimental rabbits in different time periods after HAp implantation. Material was obtained from 8 rabbits in lower jaw 6 and 8 months after HAp implants were placed. Tissues were processed for immunohistochemical detection of tumor necrosis factor alfa (TNFα), Interleukin 1, 6, 8, 10 (IL-1, IL-6, IL-8, IL-10) and defensin 2. Results demonstrated practically unchanged expression of IL-6 and IL-10 between both – experimental and control side 6 months after implantation, while IL-1 and IL-8 notably increased in control side. IL-1 and IL-10 expression did not change in either the experimental side nor the controle side after 8 months HAP implantation, but IL-6 and IL-8 demonstrated a decrease in the control sites. Only IL-8 was elevated with time in experimental sites, while IL-10 showed individual variations in 2 cases.

DRUG INFILTRATION IN POROUS HYDROXYAPATITE CERAMIC AND TISSUE RESPONSE

ABSTRACT Sintered porous hydroxyapatite (HAp) ceramics were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), optical and scanning electron microscopy (SEM). The samples were saturated with dexamethasone solution (1 mg/ml) or lidocaine solution (5 mg/ml) using vacuum method. To evaluate early reactogenity of porous synthetic impregnated HAp ceramic implants were inserted in holes of rabbits lower jaws for 2 weeks, 1 month and 3 months. Immunohistochemical methods for evaluation of growth factors and apoptosis were applied. This study aims to further comprehension of reactogenicity of HAp bioceramic implants as bone substitutes in subperiostal environment.