Bogusława Orzechowska-Wylęgała

Hydrogel membranes based on genipin-cross-linked chitosan blends for corneal epithelium tissue engineering.

Novel polymeric hydrogel scaffolds for corneal epithelium cell culturing based on blends of chitosan with some other biopolymers such as hydroxypropylcellulose, collagen and elastin crosslinked with genipin, a natural substance, were prepared. Physicochemical and biomechanical properties of these materials were determined. The in vitro cell culture experiments with corneal epithelium cells have indicated that a membrane prepared from chitosan–collagen blend (Ch–Col) provided the regular stratified growth of the epithelium cells, good surface covering and increased number of the cell layers. Ch–Col membranes are therefore the most promising material among those studied. The performance of Ch–Col membranes is comparable with that of the amniotic membrane which is currently recommended for clinical applications.

Cultivated Oral Mucosa Epithelium in Ocular Surface Reconstruction in Aniridia Patients

Purpose. Efficacy of cultivated oral mucosa epithelial transplantation (COMET) procedure in corneal epithelium restoration of aniridia patients. Methods. Study subjects were aniridia patients (13 patients; 17 eyes) with irregular, vascular conjunctival pannus involving visual axis who underwent autologous transplantation of cultivated epithelium. For the procedure oral mucosa epithelial cells were obtained from buccal mucosa with further enzymatic treatment. Suspension of single cells was seeded on previously prepared denuded amniotic membrane. Cultures were carried on culture dishes inserts in the presence of the inactivated with Mitomycin C monolayer of 3T3 fibroblasts. Cultures were carried for seven days. Stratified oral mucosa epithelium with its amniotic membrane carrier was transplanted on the surgically denuded corneal surface of aniridia patients with total or subtotal limbal stem cell deficiency. Outcome Measures. Corneal surface, epithelial regularity, and visual acuity improvement were evaluated. Results. At the end of the observation period, 76.4% of the eyes had regular transparent epithelium and 23.5% had developed epithelial defects or central corneal haze; in 88.2% of cases visual acuity had increased. VA range was from HM 0.05 before the surgery to HM up to 0.1 after surgery. Conclusion. Application of cultivated oral mucosa epithelium restores regular epithelium on the corneal surface with moderate improvement in quality of vision.

Corneal Epithelial Scaffolds Based on Chitosan Membranes Containing Collagen and Keratin

Novel biodegradable and resorbable polymeric membranes that can function as supports for corneal epithelial cells cultures were developed. The materials used to synthesize these supports are natural polymers (i.e., chitosan, collagen and keratin [7 and 17% w/w]). The membranes were crosslinked with a natural crosslinker, genipin. The physicochemical, mechanical, and biological properties of the membranes were determined. It was found that the addition of keratin results in the appearance of antibacterial properties against Escherichia coli and in increased elasticity of the membranes. GRAPHICAL ABSTRACT

The Influence of Ethanolic Extract of Brazilian Green Propolis Gel on Hygiene and Oral Microbiota in Patients after Mandible Fractures

Maintenance of proper oral hygiene by dental plaque elimination is one of the most important factors affecting the healing process in postoperative oral wounds. Propolis is a substance produced by bees. Ethanolic extract of propolis has bactericidal, fungicidal, anti-inflammatory, and antioxidative properties. Moreover, it can scavenge free radicals. The purpose of this paper is to demonstrate the efficacy of a gel containing 3% of ethanolic extract of Brazilian green propolis (EEP-B) when used for maintaining oral hygiene in patients with postoperative oral mucosal wounds. The hygiene was assessed using API, OHI, and SBI followed by microbiological examinations. The patients were divided into two groups. Group 1 consisted of those who used a gel containing EEP-B for oral hygiene, and group 2 consisted of those who used a gel without EEP-B. Although improved oral hygiene was noted in both groups, the improvement was markedly greater in the group using gel containing EEP-B. Summing up the results of microbiological examinations, EEP-B has beneficial effect on mouth microflora in postoperative period. Propolis preparations used for oral hygiene allow eliminating microorganisms of pathogenic character and physiological flora microorganisms considered as being opportunistic, with no harmful influence on physiological microflora in oral ecosystem.

Antibiotic therapies in maxillofacial surgery in the context of prophylaxis.

Objectives. There is no single pattern for preventive action as to the duration and type of antibiotic therapy in maxillofacial surgery. In these circumstances, it appears reasonable to set relevant standards for prophylactic procedures after such surgeries. Methods. Retrospective analysis of bacteriological tests has been carried out as well as a susceptibility evaluation of cultured bacterial and fungal strains to antibiotics over a five-year period in subjects treated at the Cranio-Maxillo-Facial Clinic in Katowice. A total of 726 bacterial and fungal strains were cultured in 484 patients (200 women and 284 males). The age of the patients was 40.2 on average. Results. The most frequent bacteria isolated from the patients were Gram-positive 541 (74.5%). Gram-negative bacteria were present in 177 (24.4%) cases. Fungi of the Candida genus were isolated in eight cases (1.1%). Conclusions. The most often isolated bacteria were Streptococcus mitis and Streptococcus oralis, whose number has grown over the last two years. Empiric therapies should be based on ciprofloxacin and gentamicin. It has been observed that all the Gram-positive bacteria are becoming more resistant to all antibiotics. Ampicillin and imipenem were antibiotics with the steepest resistance reduction while vancomycin showed the lowest resistance drop.

Pharmacoeconomic analysis of antibiotic therapy in maxillofacial surgery

Objectives/Aims:The aim of this study was to investigate the microbial cultures collected in the years 2013–2014 at the craniomaxillofacial department and outpatient clinic to analyse optimisation of the treatment cost of the bacterial infections and present the results.Design and setting:We analysed 485 cultures from 263 patients, of which 77.28% consisted of Gram-positive bacteria. On the basis of the antibiotic efficacy, antibiotic price and the cost of entire treatment during hospitalisation, the most useful antimicrobial agents for the most common pathogens were selected.Results:The most frequently collected material was pus. The most common pathogens were found to be the Staphylococcus epidermidis (18%), Streptococcus mitis and Str. oralis (14%) and S. aureus (6.5%).Discussion:The most frequently isolated bacteria in other studies were the Streptococcus strain. Other authors showed that ceftriaxone is the most cost efficient agent. The use of postoperative antibiotic prophylaxis remains controversial.Conclusion:The results of this study suggest that the most useful antibiotics for therapy, from the perspective of the cost minimisation, were gentamycin, trimethoprim with sulfamethoxazole and vancomycin.

Use of autologous epithelium transplantation on various scaffolds to cover tissue loss in oral cavity: long-term observation

Background The aim of this study was to investigate the application of mucous membrane keratinocyte cultures on amniotic membrane and on poly(L-lactic acid) (PLLA) Purasorb PL38 to cover tissue loss in the oral cavity. Developments in molecular biology techniques and tissue engineering allow the culturing and identification of cells that can be anchored in the wound to achieve integrity of the tissue. Transplantation of tissues obtained from the patients own cells is superior to allogenous transplantation where there is a possibility of transfection, rejection and the need for long-term immunosuppression. Methods In 9 patients (15 procedures) keratinocytes cultured on amniotic membrane and PLLA were transplanted to cover antro-oral fistulas and bone loss after osteoradionecrosis. Results In all 6 patients with outlasting antro-oral fistulas, the defects were healed. In 3 patients with 5 cases of tissue loss after osteoradionecrosis, we obtained healing of the wound in only 1 case. Histological examination of the cultures indicated that cultured cells formed well-differentiated layers, very similar to the keratinocytes of mucous membranes, although those seeded on amniotic membrane formed a single layer of cells, while those seeded on the PLLA scaffold were arranged on 2 or more layers: these differences were shown to be statistically significant with a morphometric analysis. Conclusions Autologous transplants of epithelium cultured on amniotic membrane and PLLA constitute a new and effective way of covering nonhealing tissue loss in the oral cavity in chosen cases, using modern methods of tissue engineering.

Epithelial thickness and structure in patients with congenital aniridia after COMET procedure

Purpose To evaluate epithelial structure after COMET procedure in patients with congenital aniridia.

Cultivating oral mucosa epithelial transplantation (COMET) followed by penetrating keratoplasty (PK) in ocular surface reconstruction

Purpose Efficacy of COMET and subsequent PK in patients with limbal insufficiency combined with stromal corneal haze after corneal burns