Atanas Chonin

Recent EU regulations recommend restriction of the use of medical devices in which cobalt content exceeds 0.1%. Commercially pure titanium (cpTi) and titanium alloys appear to be excellent alternatives to cobalt-based alloys in the fields of implantology and prosthodontics. The narrative review summarizes the structure and types of titanium alloys and the methods of their processing. The high biocompatibility of titanium is explained in terms of corrosion, ion release, and interaction with the biological environment. An analysis of existing studies on the mechanical properties of titanium prosthetic restorations is presented, and future perspectives are outlined.

The aim of this literature review was to provide a brief perspective over the scientific research of the condition known as burning mouth syndrome. Information from review articles, original studies, and dissertations was gathered using keywords describing etiological factors, clinical, laboratory findings and treatment protocols. We compiled information on potential etiological factors, symptoms, and potential treatments from the fifty-three included studies on dental and general health issues in patients complaining of burning sensations in their mouths. Despite the numerous attempts by dental and medical professionals to diagnose and treat mouth burning, the etiology and pathogenesis of this disorder remain rather unclear. In most cases, it is concluded that further research is needed with the inclusion of more patients, administering a long-term therapy, and monitoring the results.

Introduction: CAD/CAM technologies are becoming widely used for the production of metal ceramic dental restorations. Powder Co-based alloys are developed for selective laser melting. The corrosion resistance of the dental alloy affects the biocompatibility, functional suitability, and longevity of the prosthetic restoration. Aim: The aim of this study was to evaluate and compare the corrosion resistance of a cobalt-chromium dental alloy for porcelain-fused-to-metal (PFM) crowns produced for selective laser melting technique in clinical and laboratory conditions. Materials and methods: PFM crowns were made for 35 patients using CAD/CAM technology. The metal copings of the crowns were made of the EOS CobaltChrome SP2 alloy (EOS, Germany). Eocp measurements were conducted 2 hours and 7 days after fixing the restorations in oral cavity. The digital files of patients’ designed copings were used for the production of another 35 specimens, which were placed in artificial saliva. Eocp measurements were conducted after the same periods. Results: In vitro studies showed high corrosion resistance after the short 2-hour stay. After 7 days in artificial saliva, the corrosion resistance became even higher probably due to strong passivation. In clinical conditions, Eocp values were slightly higher than the normal range 2 hours after fixing the crowns. Seven days after fixing, the Eocp values showed a decrease of corrosion resistance of the PFM crowns. The cause of the decrease may be interaction with other metal objects or specific conditions of the oral cavity. Conclusions: The investigated alloy showed high corrosion resistance in in vitro settings. Clinical research revealed that PFM crowns had lower corrosion resistance. Further observation and research are required.

Introduction: Methacrylate-based materials are used daily in dental practice. Specialized publications report these materials as allergens with a high sensitizing potential.Aim: To draw the attention of dental doctors and personnel to risk factors of developing occupational allergies.Materials and methods: History and dermatological status of the patient were taken and he was given an epicutaneous test.Results: The allergy testing revealed a strong positive allergic reaction to methacrylates which persisted and was observed at 72 hours as well as on day 7. A diagnosis of allergic contact dermatitis was made on the basis of the patient’s history, the clinical examination and the results of the epicutaneous test.Conclusion: The presented clinical case shows that early identification of the specific causative agents allows clinicians to take adequate measures and achieve results without having to use a medicine, and stop the progression of the occupational disease and the development of complications.

Background: Dental students are at high risk of developing adverse respiratory reactions as a result of their practical work during their dentistry degree program when they come into contact with multiple airborne irritants and allergens. Aim: To estimate the prevalence of respiratory symptoms of exposure to substances in the workplace and associated risk factors in Bulgarian dental students. Materials and methods: A cross-sectional study of dental students at the Plovdiv Medical University and Sofia Medical University was performed by using a self-report questionnaire. A total of 467 dental students completed the questionnaire (response rate 51.8%). Results: The prevalence of self-reported respiratory symptoms related to the pre-clinical and clinical training courses of the dentistry program was 12.4%. According to logistic regression analysis, the most important risk factors for work-related respiratory symptoms were a personal history of allergic rhinoconjunctivitis (odds ratio (OR) 6.34, 95% confidence interval (CI): 3.14-12.78), atopic dermatitis (OR 2.81, 95%CI: 1.26-6.26), and exposure to chemicals from dental environment for more than 6 hours a day (OR 3.60, 95%CI: 1.21-10.70). Conclusion: The results of this study suggest that work-related respiratory symptoms are frequent among dental students and indicate the need for efforts to establish effective primary preventive programs for occupational respiratory disorders at national level.

After acrylic resins have been developed they found a broad area of application. Today they have totally replaced the amalgam and are used in the manufacturing of dental prosthesis, restorative materials, root canal filling materials, bonding materials and glass ionomers. As a consequence, the number of allergic reactions to these materials is increasing.\ud Purpose: The aim of this study was to evaluate the most common intraoral clinical manifestations of allergic reactions to plastic materials used in dentistry.\ud Materials and methods: The study population consisted of 200 interviewed participants divided into two groups: dental patients with methacrylic restorations and occupationally exposed to methacrylates manicurists and dental technicians. All of them had dental treatments with acrylic materials. 154 of them were patch tested with 24 methacrylate allergens compiled from (Meth)Acrylate Series Adhesives, Dental & Other, (Meth)Acrylate Series - Nails Artificial Series (MN- 1000) (Chemotechnique Diagnostics Vellinge, Sweden). 30 patients (19.48%) showed positive reactions to tested substances.\ud Results: Erythema was observed in 8 (26.66 %) patients, edematous changes in oral tissues in 4 (13.33%) patients. In 60% of patients with positive reactions, there were no intraoral findings. Aphthous or lichenoid eruptions which are specific for contact allergy to dental materials were not registered during intraoral inspections.\ud Conclusions: According to results of this study we cannot confirm that there are specific intra or extra oral changes pathognomonic for methacrylate allergy in dental patients