Oral surgery for combined haemophilia A and B. The dos and don'ts presented in a clinical scenario.

BACKGROUND: Haemophilia A (factor VIII deficiency), B (factor IX deficiency) and C (factor XI deficiency) are common genetic bleeding disorders. Most often they are caused by the absence or defective function of coagulation factors, causing inefficient blood clots. CASE REPORT: The present manuscript describes a rare case of a combined haemophilia A and B patient, who underwent several extractions. The therapy and clinical management is presented, in the view of surgeon as well as haematologist. CONCLUSION: These patients are a serious challenge for the oral surgeons due to an increased number of accidents and complications. Scarce literature covering this topic contributes, as well, to the difficult management. Thus, several principles must be considered when diagnosing and treating haemophilia patients. KEY WORDS: Haemophilia, Oral surgery.

Observational study of the bisphosphonate-related osteonecrosis of jaws.

INTRODUCTION: The bisphosphonate-related osteonecrosis of the jaw was first referred to in 2003. Bisphosphonates action is focused on the osteoclasts. The drastic inhibition of the osteoclastic function is harmful for the jaws which are the only bones of the human skeleton in relative contact with the external environment. The adverse effects of the bisphosphonate-related therapy include the pathology for which they are prescribed, the atypical fractures in pathological bone. METHOD: The aim of this research was to analyze the risk factors and the treatment methods in case of osteonecrosis of the jaws. To achieve these goals, the author analyzed the observation sheets of the patients admitted to the Oral and Maxillofacial Surgery Clinic during the period 2010-2015. The inclusion criteria were as follows: treatment with bisphosphonates, current or previous; the lesions of the mucous gingiva of the maxillaries followed by exposed necrotic bone, older than 8 weeks, with no tendency of healing; specific radiological image showing extended osteolysis with diffuse outline or radiopacity surrounded by radio-transparence, representing the necrotic bone sequestered; no metastasis in the necrotic maxillary bone; patient with no medical background of cervical-facial radiations. The patients who met these criteria were admitted in the study after signing the informed consent. Afterwards, the information found in the notes of the observational sheet (anamnesis, general examination and the imagistic investigation, treatment, postoperative recovery, prescription, postoperative recommendations) were gathered and submitted for statistic analysis. RESULTS: Of the 20 patients in total, 13 were women and 7 men, of ages ranging from 43 to 83. The most numerous cases were registered in the seventh age decade. All patients included in the study had lesions of the gingival maxillary mucosal areas with exposure of the subjacent necrotic bone. 60% of them were under intravenous treatment with zoledronic acid (Zometa®). A single patient was under oral treatment with bisphosphonates. 19 of these 20 patients developed osteonecrosis following a dental extraction while one case was due to the instability of the mandibular mobile prosthesis. 61% of the patients included in the study developed a necrotic process in the mandibular bone, 80% of the localizations were in the posterior area. As first intention, the choice of treatment was represented by local lavages with antiseptic solutions, general antibiotics and sequestrectomy. Of these patients, a third had relapsed and needed radical surgery treatment. CONCLUSIONS: Prevention of the bisphosphonate-related osteonecrosis of the jaw represents the best method of treatment. The development of bone sequesters damages the volume of the maxillary bone as such, reducing the chances for prosthetic functional rehabilitation of the dento-maxillary system. An increase in the quality of life by oral restoration of these patients may represent a challenge.

Evaluation of the Biocompatibility of New Fiber-Reinforced Composite Materials for Craniofacial Bone Reconstruction.

This study aims to assess the biocompatibility of new advanced fiber-reinforced composites (FRC) to be used for custom-made cranial implants. Four new formulations of FRC were obtained using polymeric matrices (combinations of monomers bisphenol A glycidylmethacrylate [bis-GMA], urethane dimethacrylate [UDMA], triethylene glycol dimethacrylate [TEGDMA], hydroxyethyl methacrylate [HEMA]) and E-glass fibers (300 g/mp). Every FRC contains 65% E-glass and 35% polymeric matrix. Composition of polymeric matrices are: bis-GMA (21%), TEGDMA (14%) for FRC1; bis-GMA (21%), HEMA (14%) for FRC2; bis-GMA (3.5%), UDMA (21%), TEGDMA (10.5%) for FRC3, and bis-GMA (3.5%), UDMA (21%), HEMA (10.5%) for FRC4. Cytotoxicity test was performed on both human dental pulp stem cells and dermal fibroblasts. Viability was assessed by tetrazolium dye colorimetric assay. Subcutaneous implantation test was carried out on 40 male Wistar rats, randomly divided into 4 groups, according to the FRC tested. Each group received subcutaneous dorsal implants. After 30 days, intensity of the inflammatory reaction, tissue repair status, and presence of the capsule were the main criteria assessed. Both cell populations showed no signs of cytotoxicity following the FRC exposures. In terms of cytotoxicity, the best results were obtained by FRC3 followed by FRC2, FRC4, and FRC1. FRC3 showed also the mildest inflammatory reaction and this correlated both with the noncytotoxic behavior and the presence of a well-organized capsule. The composite biomaterials developed may constitute an optimized alternative of the similar materials used for the reconstruction of craniofacial bone defects. According to authors' studies, the authors conclude that FRC3 is the best formulation regarding the biological behavior.

Antibacterial coating on biocomposites for cranio-facial reconstruction.

BACKGROUND AND AIMS: Despite the fact that implants are sterilized, antiseptic techniques are applied and systemic antibiotics are routinely administered prior to and after craniofacial surgery, infection rates between 3% and 40% are still reported for alloplastic implants, urging for implant removal. The present study focuses on the development of a fiber-reinforced composite (FRC) implant for craniofacial reconstruction with antimicrobial properties. METHODS: A new fiber-reinforced composite coated with gentamicin was developed and tested for bacterial adherence and antibacterial efficiency, using two of the most involved bacterial strains in the postoperative infections: Staphylococcus aureus and Pseudomonas aeruginosa. RESULTS: Bacteria were efficiently inactivated in direct contact with gentamicin coatings (p<0.05). The inhibition zone for Staphylococcus aureus ranged from 17.21 mm to 20.13 mm and for Pseudomonas aeruginosa ranged from 12.93 mm to 15.33 mm. Although no significant statistical results were found for bacterial adhesion and gentamicin concentration, (Staphylococcus aureus: ß= -0.974; p=0.144>0.05 and Pseudomonas aeruginosa: ß = -0.921; p=0.255>0.05), a negative relation was observed, indicating the reversed relation between the antibiotic dosage and the bacterial adherence. CONCLUSION: The results of the two applied microbiological protocols used in the study suggested that gentamicin eluting coating inhibited not only the bacterial growth, but also led to a lower initial bacterial adhesion to the surface of the implant. Thus, antibiotic coating of craniofacial implants may reduce the infection rate related to reconstructive surgery.