Review of nanomaterials in dentistry: interactions with the oral microenvironment, clinical applications, hazards, and benefits.

Interest in the use of engineered nanomaterials (ENMs) as either nanomedicines or dental materials/devices in clinical dentistry is growing. This review aims to detail the ultrafine structure, chemical composition, and reactivity of dental tissues in the context of interactions with ENMs, including the saliva, pellicle layer, and oral biofilm; then describes the applications of ENMs in dentistry in context with beneficial clinical outcomes versus potential risks. The flow rate and quality of saliva are likely to influence the behavior of ENMs in the oral cavity, but how the protein corona formed on the ENMs will alter bioavailability, or interact with the structure and proteins of the pellicle layer, as well as microbes in the biofilm, remains unclear. The tooth enamel is a dense crystalline structure that is likely to act as a barrier to ENM penetration, but underlying dentinal tubules are not. Consequently, ENMs may be used to strengthen dentine or regenerate pulp tissue. ENMs have dental applications as antibacterials for infection control, as nanofillers to improve the mechanical and bioactive properties of restoration materials, and as novel coatings on dental implants. Dentifrices and some related personal care products are already available for oral health applications. Overall, the clinical benefits generally outweigh the hazards of using ENMs in the oral cavity, and the latter should not prevent the responsible innovation of nanotechnology in dentistry. However, the clinical safety regulations for dental materials have not been specifically updated for ENMs, and some guidance on occupational health for practitioners is also needed. Knowledge gaps for future research include the formation of protein corona in the oral cavity, ENM diffusion through clinically relevant biofilms, and mechanistic investigations on how ENMs strengthen the tooth structure

Dental pulp tissue engineering

Dental pulp is a highly specialized mesenchymal tissue, which have a restrict regeneration capacity due to anatomical arrangement and post-mitotic nature of odontoblastic cells. Entire pulp amputation followed by pulp-space disinfection and filling with an artificial material cause loss of a significant amount of dentin leaving as life-lasting sequelae a non-vital and weakened tooth. However, regenerative endodontics is an emerging field of modern tissue engineering that demonstrated promising results using stem cells associated with scaffolds and responsive molecules. Thereby, this article will review the most recent endeavors to regenerate pulp tissue based on tissue engineering principles and providing insightful information to readers about the different aspects enrolled in tissue engineering. Here, we speculate that the search for the ideal combination of cells, scaffolds, and morphogenic factors for dental pulp tissue engineering may be extended over future years and result in significant advances in other areas of dental and craniofacial research. The finds collected in our review showed that we are now at a stage in which engineering a complex tissue, such as the dental pulp, is no longer an unachievable and the next decade will certainly be an exciting time for dental and craniofacial research

Ten years' clinical evaluation of three luting cements

ABSTRACT Objective: The aim of the present clinical longitudinal study was to observe, over 10 years, the prognosis of abutment teeth restored with fixed prostheses retained by two glass ionomer luting cements and one conventional zinc phosphate cement. Methods: Three dentists prepared 135 abutment teeth in 61 patients to retain 81 fixed prostheses. The prostheses were retained by two glass ionomer luting cements (Ketac-Cem, ~uji Ionomer), ~r a conventional zinc phosphate cement (De Trey Zinc Zement Improved). The patients were exammed yearly for 10 years. . . . Results: Post-operative hypersensitivity occurred in five teeth restored With glass lOnomer lutmg cement. The prevailing reason for abutment tooth failure was secondary caries (n = 21) and pulp ne~rosis (n = 5). Non-parametric survival estimates indicated that 80-85% of the abutment teeth remamed mtact after 5 years and 71-81 % after 10 years. . Conclusions: The 10-year results indicate that the prognosis of abutment teeth restored With fixed prostheses is good, regardless of whether a glass ionomer or a zinc phosphate luting cement is used