Evaluation of Soft Tissue Reaction to Corundum Ceramic Implants Infiltrated with Colloidal Silver.

BACKGROUND: Corundum ceramic is a biomaterial used as a bone graft substitute. Silver is a well known antiseptic substance with many practical, clinical applications. OBJECTIVES: The aim of this study was to estimate soft tissue (in vivo) reaction to a new kind of ceramic implants. In our experiment, we examined the soft tissue reaction after implantation of corundum ceramic infiltrated with colloidal silver in the back muscles of 18 Wistar rats. The use of colloidal silver as a coating for the implant was designed to protect it against colonization by bacteria and the formation of bacterial biofilm. MATERIAL AND METHODS: In our study, based on the experimental method, we performed implantation operations on 18 Wistar rats. We implanted 18 modified ceramic implants and, as a control group, 18 unmodified implants. As a follow up, we observed the animals operated upon, and did postoperative, autopsy and histopathological examinations 14, 30, 90 and 180 days after implantation. RESULTS: We didn't observe any pathological reactions and significant differences between the soft tissue reaction to the modified implants and the control group. CONCLUSIONS: Lack of pathological reaction to the modified implants in the living organism is the proof of their biocompatibility. This is, of course, the first step on the long path to introduce a new kind of biocompatible ceramic implant with antiseptic cottage. Our experiment has an only introductory character and we plan to perform other, more specific, tests of this new kind of implant.

The role of laser biostimulation in early post-surgery rehabilitation and its effect on wound healing.

BACKGROUND: The aim of this paper is to investigate whether laser biostimulation starting on the first day after surgery of the brachial plexus or peripheral nerves has a positive therapeutic effect on wound healing. MATERIAL AND METHODS: Surgical procedures were carried out on 44 male Wistar rats. The animals were divided into a control group (Group 1), where the surgical wounds were allowed to heal spontaneously, and an experimental Group 2, where the wounds were exposed to laser irradiation with the following parameters: wavelength 810 nm, power 100 mW, energy 15 J, laser exposure surface 3 cm(2), single application time 2 min. 30 sec., continuous mode. The results were assessed with pathomorphological tests (gross appearance of the wound, light and electron microscopy studies) and breaking strength examination. Statistical analysis used arithmetic means, standard deviations and Student's t test for independent samples. RESULTS: Low energy infrared laser radiation had a beneficial effect on the covering of the scar with stratified squamous cornifying epithelium and intensified wound healing. CONCLUSIONS: The gross and microscopic findings indicated a beneficial effect of laser stimulation on wound healing. These results underscore the utility of biostimulation lasers in the early post-operative period. Physicomechanical investigations did not reveal an effect of infrared laser biostimulation on the breaking strength of the cutaneous scar.

Ceramic corundum materials with modified surface as implantation materials.

Investigations on implants have proved that not only the kind of material structure, but also the surface character of grafts influences the local reaction of biomaterials. In recent years electrochemical reactions on implants surface leading to the so called zeta potential arouse interests. Applications of these properties has made us carry on experiments on use of biomaterials with active potential on their bio-compatibility. The aim of this work is evaluation of influence of electrical charge with zeta potentials character on the local reaction of bone tissue after implantation. Two kinds of ceramics were used in experiments: solid and solid-silane with active surface. Implantation experiments were made on 20 rabbits. Selections were carried of 12, 26, 36 and 54 weeks after implantation of the tested materials. After implantation of solid ceramics, not only bone tissue but also fibrous tissue was observed around the graft. But in case of solid silane ceramics, in all terms of tests, bone tissue tightly sticking to the implant was observed around the graft. Investigations of electrokinetic zeta potential carried out 36 and 54 weeks after implantation showed that the values of that potential originally introduced on the grafts surface were maintained on stable level. The carried out investigations confirmed that activation of implants surface through silaning with sol-gel method allows to introduce the planned zeta potential depending on the characteristic for a given kind of tissue.

[Effect of corundum-vancomycin composite on soft tissue reaction]. / Wplyw kompozytu korundowego z Wankomycyna na odczyn tkanek miekkich.

The ceramics on the basis of corundum is used for implantation in the form of porous and solid materials. The solid form was used to produce tissue endoprosthesis while porous form is mainly used to fill in the bone defects. The corundum ceramics are also known to be used as coatings for implants in orthopedics and dentistry. On the other hand there is still a need to find out the new way of treatment of the chronic bone infection, during which the traditional way of antibiotics therapy is no more effective. One of the possibly solution is to use the different biomaterials as drug carriers and in the bone surgery one of the best are porous corundum implants, being themselves of high biocompatibility, and additionally containing Vancomycin. The main target of the investigation presented in this paper was the comparative assessment of the corundum ceramics and its composite containing Vancomycin after implantation into back muscle of the total of 15 rats. During the post mortem macroscopic assessment in the tissues which surrounded the implants there were no any inflammatory neither pathological changes observed. In the microscopic findings, in early periods, the observed inflammatory tissue reaction for implants with vancomycin was significantly greater what could be explained by the high concentration of the antibiotic in the given material. On the basis of the results of macroscopic and microscopic findings we can state that the composite material of corundum ceramic containing vancomycin is of high compatibility and could be regarded as the good drug carrier.

[The bone reaction to the implantation of the corundum-vancomycin composite]. / Reakcja tkanki kostnej po implantacji ceramiki korundowej z Wankomycyna.

Polymethacrylate methylene (PMMA) used as the carrier for antibiotic gentamycin (Septopal) shows today very limited effectiveness. Only 24% of the staphylococcus strains is still susceptible for it. In 1982 this factor was as high as 97%! Because of the growing resistance of different strains of staphylococcus, enterococcus and G(-) bacillus for antibiotics in present use, came into being the necessity for evaluation of the state-of-the-art antibiotic carrier of the new generation, which should be effective to destroy the resistant strains of bacteria. The porous corundum ceramics proved to be good material for this purpose, specially in use for bone surgery. During the laboratory tests it was confirmed that corundum ceramics could be soaked with the different antibiotics of the new generations. The bacteriological tests proved that corundum ceramics soaked with the Vancomycin show the highest possibly antibacterial activity. On the basis of those results we undertook the implantation test on animals. The implantation was carried out on 10 rabbits in which the samples of tested ceramic with Vancomycin were implanted into femoral bone. The investigation periods were set up for 1, 3, 6 and 9 months. On the basis of received results of macroscopic, microscopic and radiological findings we can stated that corundum ceramic with Vancomycin can be used in the treatment of bone infections.