Indirect Restorative Polymeric Dental Materials

The current chapter, entitled “Indirect restorative polymeric dental materials,” is dedicated to one class of dental materials with wide indications in dental medicine. The chapter is an overview of polymeric resin composites dedicated to indirect restauration currently used and latest avail resin composite and polymers in dentistry. This chapter includes chemical composition, indications, light-curing mechanism and physical and mechanical properties of indirect conventional and new polymeric materials. Important aspects about resin composites are related to clinical and physical properties such as light-curing, aesthetics, wear rates and biocompatibility. The accuracy and longevity of indirect composite restorations depend on choosing the right material according to clinical requirements, material’s properties, and behaviour in the oral cavity and clinical indications. The chemical composition of resin composite, curing mechanism and advantages of these materials are presented in Introduction. The second section is dedicated to structure and composition of indirect polymers, indirect resin composites, first and second generation of indirect resin composites and their indications. Section 3 describes the structure and composition of high-performance hybrid polymers, hybrid ceramic and high-performance polymers, and poly ether ketone ketone dedicated to different processing technologies

Dental Anatomy and Morphology of Permanent Teeth

The present chapter is proposing a detailed and illustrated description of dental morphology of permanent dentition. The main topics are related to nomenclature, age of emergence, a description of teeth’s tissues (pulp, dentin, enamel, and cement), and morphology of all permanent teeth. The main focus of this chapter is the description of individualized morphology and specific variations of each permanent tooth. The goal of all treatment phases in dental medicine is to restore the function, integrity, and morphology of the oral cavity, and all these achievements are reached through deep knowledge of dental morphology. Cavities are restored with direct dental materials, which need to be carved according to the natural shape, outlines, occlusal and proximal contacts of teeth’s morphology, reproducing also the shade and translucencies of natural teeth. The same goal dominates the prosthodontic field. It is well known in dental medicine that shape, size, and position assure the optimal function and preserve the self-maintenance of dental arches and dento-maxillary system. For esthetic, function, and self-preservation, all dental treatment fields have to first consider the dental morphology

ETHICS AND MEDICAL LEGISLATION IN RETROSPECTIVE EXPERIMENTAL STUDIES. THE ROLE AND IMPORTANCE OF THE LEGISLATIVE ASPECT

Aim of the study Ethical problems most often arise in research. One of the most important ethical rules governing research on humans is that participants must give their informed consent before taking part in a study. Informed consent is therefore a vital part of the research process, and as such entails more than obtaining a signature on a form. Most researchers however, do not have the requisite knowledge of the importance of informed consent in research. This paper attempts a synopsis of the place of informed consent in research study. Materials and methods A review of literature on informed consent in research. Literature search was done using Google search engine as well as international and local journals. Results Informed consent as an aspect of medical ethics, balances autonomy and beneficence, and provides adequate assurance of voluntary and autonomous participation without negative repercussions on access to study benefits. The search showed that this if adhered to in research, will surely maintain the dignity of man and the integrity of research as a field of human endeavour. Conclusions Researchers must therefore ensure that potential research participants be given sufficient information about a study, in a format they understand, to enable them to exercise their right to make an informed decision whether to participate in a given research

NUTRITIONAL PROFILING AND SENSORY EVALUATION OF NOVEL HOT CHOCOLATE RECIPES: A COMPARATIVE STUDY WITH A COMMERCIAL BRAND

Aim of the Study: The study aimed to develop and evaluate two new hot chocolate recipes (P1 – Red Recipe and P2 – Green Recipe) and compare them with a commercial hot chocolate product (P3 – “La Festa”). The focus was on creating recipes that are nutritionally comparable to natural or dietetic products, with reduced sugar and increased dietary fibre content. Materials and Methods: The study employed sensory evaluation methods, specifically the Mann-Whitney and Wilcoxon Sign Rank tests, to assess appearance, consistency, flavour, taste, and smell of the hot chocolate recipes. Additionally, a comprehensive nutritional analysis was conducted to compare the protein, lipid, carbohydrate, fibre, and caloric content of the recipes against the commercial product. Results: The sensory evaluation revealed that Recipe P1 significantly outperformed both Recipe P2 and the commercial product P3 in all tested attributes. Nutritionally, Recipes P1 and P2 were similar, both showing lower sugar and higher fibre content than typical market products. However, no significant sensory differences were noted between Recipe P2 and the commercial hot chocolate P3. Conclusions: The study concludes that Recipe P1 is superior in sensory qualities with a favourable nutritional profile, making it an appealing option for health-conscious consumers. Recipe P2, while nutritionally akin to P1, shares more sensory similarities with traditional hot chocolate, offering a healthier alternative without sacrificing familiar flavours. This research underscores the feasibility of creating healthier versions of popular beverages without compromising taste and sensory appeal

ASSESSMENT OF DENTAL CERAMIC SINTERED AT DIFFERENT TEMPERATURES

Aim of the Study: The aim of this study is to investigate the modifications that may occur in case of sintering temperature deviation for metal-ceramic crowns. Materials and Methods: For this in vitro study were made 15 metal-ceramic crowns for tooth 2.1 and were divided into 5 groups. The ceramic veneering comprised different sintering temperatures optimized for different properties: group 1 was sintered at 910 ºC as per the manufacturer’s recommendation, group 2 was sintered at 940ºC (+30 ºC), group 3 was sintered at 960ºC (+50 ºC), group 4 was sintered at 880ºC (-30 ºC), and group 5 was sintered at 860 ºC (-50 ºC). Using the EXOCAD scanner the maxillary cast was scanned to obtain the metal frameworks from Cr-Co alloy (SCHEFTNER CoCr – 30 microns). Ips InLine One ceramic shade A3 developed by Ivoclar Vivadent Inc is applied in two layers, each one sintered at the same temperature. After ceramic sintering, the shade of each group was registered with Vita Easy Shade spectrophotometer and Vitapan Classical shade guide. Results: Errors in sintering temperatures can change the ceramic’s density and mechanical properties but may also lead to colour shifts. This phenomenon occurs due to alterations in the ceramic material’s microstructure, which can impact its optical properties and, consequently, its perceived colour. Conclusions: In conclusion, our study highlights the crucial impact of sintering temperature variations on the quality and integrity of metal-ceramic dental restorations. Our findings point towards the need for further innovation and research in thermal management within dental ceramics processing to achieve restorations that are not only aesthetically pleasing but also functionally reliable and compatible with the natural dentition

IMAGING EVALUATIONS OF UNICA CERAMICS UNDER THERMAL CYCLE CONTROL CONDITIONS

Aim of the study: To evaluate the efficacy of Optical Coherence Tomography (OCT) in non-invasively monitoring temperature variations during ceramic sintering for dental prosthetics, emphasizing the importance of precise temperature control for optimal material properties and structural integrity. Materials and Methods: The study utilized OCT to examine 17 metal-ceramic restorations at various sintering temperatures (standard, 80°C below, and 50°C above the standard). The method involved generating 61 cross-sectional images per prosthesis to identify defects and structural changes. Results: OCT revealed significant insights into the impact of temperature deviations on ceramic microstructure, including uniform grain sizes at standard temperatures and areas of reduced retention at elevated temperatures, highlighting the technology’s potential in quality control. Conclusions: OCT offers a rapid, accurate, and non-destructive means to assess sintering temperatures and detect defects in dental ceramics, facilitating improvements in dental prosthetics’ fabrication process. The study advocates for OCT’s integration into routine dental laboratory practices to enhance prosthesis quality and reliability