Hydroxyapatite is one of the most studied biomaterials in the medical and dental field, because of its biocompatibility; it is the main constituent of the mineral part of teeth and bones. In dental science, hydroxyapatite nanoparticles (HAnps) or nano-hydroxyapatite (nano-HA) have been studied, over the last decade, in terms of oral implantology and bone reconstruction, as well in restorative and preventive dentistry. Hydroxyapatite nanoparticles have significant remineralizing effects on initial enamel lesions, and they have also been used as an additive material in order to improve existing and widely used dental materials, mainly in preventive fields, but also in restorative and regenerative fields. This paper investigates the role of HAnps in dentistry, including recent advances in the field of its use, as well as their advantages of using it as a component in other dental materials, whether experimental or commercially available. Based on the literature, HAnps have outstanding physical, chemical, mechanical and biological properties that make them suitable for multiple interventions, in different domains of dental science. Further well-designed randomized controlled trials should be conducted in order to confirm all the achievements revealed by the in vitro or in vivo studies published until now.

Zirconia-reinforced lithium silicate (ZLS) ceramic is a new innovative dental material with unique a chemical composition that is designed to combine harmoniously with the appropriate optical properties of lithium disilicate and the enhanced mechanical strength of zirconia. A thorough understanding of ZLS materials is essential for both clinicians and dental technicians. At present, the mechanical behavior and optical properties of the ZLS ceramic system have not been extensively researched, and there is still a lack of consensus regarding the fabrication process and clinical behavior of ZLS all-ceramic restorations. The aim of the present study was to present a selection of comprehensive information concerning zirconia-reinforced lithium silicate ceramics and their optical and mechanical properties, as well as to assess data regarding cementation procedures and clinical outcomes for ZLS all-ceramic restorations. Three electronic databases (PubMed, Web of Science, and the Cochrane Library) were used for the research by two independent reviewers. The search was limited to articles published in the English language, as well as clinical and in vitro studies of color and studies on mechanical behavior and the cementation procedures of ZLS restorations. The exclusion criteria comprised abstracts, questionnaire-based studies, case reports, literature reviews, and studies that were not available in English. Zirconia-reinforced lithium-silicate-based ceramic presents a unique and complex microstructure that increases mechanical resistance but decreases aesthetic appearance, especially its translucency, due to tetragonal zirconia content. A material’s thickness, the color of the underlying tooth structure, and the resin cement shade are important factors that influence the final shade and aesthetic appearance of ZLS restorations. Mechanical properties, which are defined by the fracture toughness, flexural strength, elastic modulus, and hardness of ZLS ceramic are higher compared to feldspathic, lithium disilicate, and hybrid ceramics, as well as resin nanoceramics; however, they are lower than translucent or high-translucency zirconia. Acid etching, sandblasting, and laser etching represent the most used methods to prepare the ZLS restoration surfaces for proper bonding procedures.

Background: For the past two and half years, dentists all across the world, along with their patients, have faced numerous challenges. In this context, the aim of this integrative review was to assess if dentists’ and patients’ attitudes regarding teledentistry (TD) have changed since the COVID-19 outbreak, and if the use of TD will continue to rise, even in the post-pandemic period; (2) Methods: A literature search was performed between August 2021 and January 2022. The PubMed, Scopus, and Science Direct databases were searched for articles published between 2012 and 2022 using a combination of the following Mesh terms: “COVID-19”, “pandemic”, “oral telemedicine”, “teledentistry”; (3) Results: Among the 52 included papers, nine papers were published between 2011 and 2019, and 43 articles were published after 2020 (12 were published in 2020, 29 papers were published in 2021, and two in 2022). Among the articles published before 2020, seven out of nine included papers were reviews, and two were original research. Among the 43 papers published after 2020, 18 were reviews and 25 original research. (4) Conclusions: Based on the results of this integrative review, there is clear evidence that the interest in teledentistry and teleassistance in the dental field has increased rapidly, especially in the context of the COVID-19 pandemic. Therefore, while dental practitioners should be encouraged to keep themselves updated about new technologies, patients should also be constantly informed about their options for receiving special oral health care.

Background: In dental practice, different situations require etching the enamel layer. Acid etching, the present golden standard, may be replaced by other methods, such as laser etching. The main focus of our scoping review is to assess the existent literature regarding the effectiveness of different types of lasers, to identify the main aspects studied so far, and to understand where new search strategies are needed. Methods: The search was conducted in several databases focusing on the laser etching of human definitive enamel. We included English language articles published between January 2000 and December 2021. Results: The 34 articles reviewed showed that hard lasers, Er:YAG, Er,Cr:YAG, may represent an alternative etching method on enamel surfaces. They create a fractured, irregular surface and open dentin tubules, highly suitable for adhesion but with a lower risk of cavity formation. Nd:YAG, CO₂, and Diode lasers do not help in creating sufficient shear bond strength. There is, however, evidence suggesting that microcracks in the enamel layer may appear after thermomechanical ablation using laser energy. Conclusions: While the use of acid etching is still successfully used for enamel conditioning, some researchers have emphasized the role played by saliva in the enamel-remineralization process a few days after the procedure. In this context, laser energy can be used, especially for bonding ceramic brackets in the case of orthodontic treatments. However, as thermomechanical ablation can generate microcracks, further research is required in order to establish clear findings concerning the use of laser energy on enamel etching.

Background and aims. Vitamin D is synthesized in the skin with the aid of ultraviolet-B radiation, playing a variety of roles in the body. Temporomandibular disorders (TMDs) are a group of pathological conditions involving the temporomandibular joints as well as the masticatory muscles and othersurrounding tissues. In the present narrative review, we investigated the potential role of vitamin D in the etiology of temporomandibular disorders in order todetermine whether the current knowledge supports 25-hidroxyvitamin D (25-OHD) supplementation in temporomandibular disorders associated with insufficient or deficient levels of vitamin D. Methods. A literature research was performed in PubMed, Scopus, Science Direct, and Google Scholar databases, and a total of 10 articles were included for analysis. Results.Among the observational studies published to date, investigating the role for vitamin D in the etiology of TMDs, six of them suggest that there is a connection between the two aspects. In this context, patients suffering from TMD, with deficient levels of vitamin D (50ng/mL probably have little benefit from supplementation.Conclusion.Vitamin D might be a safe, simple, and potentially beneficial way to prevent TMDs or to reduce pain; however, more randomized and placebo-controlled trials are required before any firm conclusions can be drawn.

Over the past two decades, dental ceramics have experienced rapid advances in science and technology, becoming the fastest-growing field of dental materials. This review emphasizes the significant impact of translucent zirconia in fixed prosthodontics, merging aesthetics with strength, and highlights its versatility from single crowns to complex bridgework facilitated by digital manufacturing advancements. The unique light-conducting properties of translucent zirconia offer a natural dental appearance, though with considerations regarding strength trade-offs compared to its traditional, opaque counterpart. The analysis extends to the mechanical attributes of the material, noting its commendable fracture resistance and durability, even under simulated physiological conditions. Various zirconia types (3Y-TZP, 4Y-TZP, 5Y-TZP) display a range of strengths influenced by factors like yttria content and manufacturing processes. The study also explores adhesive strategies, underlining the importance of surface treatments and modern adhesives in achieving long-lasting bonds. In the realm of implant-supported restorations, translucent zirconia stands out for its precision, reliability, and aesthetic adaptability, proving suitable for comprehensive dental restorations. Despite its established benefits, the review calls for ongoing research to further refine the material’s properties and adhesive protocols and to solidify its applicability through long-term clinical evaluations, ensuring its sustainable future in dental restorative applications.