Strontium acetate is applied for dental hypersensitivity treatment; however, the use of strontium carbonates for this purpose has not been described. The use of Sr-carbonate nanoparticles takes advantage of both the benefits of strontium on dentin mineralization and the abrasive properties of carbonates. Here in, we aimed to synthesize strontium carbonate and strontium-substituted calcium carbonate nanoparticles and test them as potential compounds in active dentifrices for treating dental hypersensitivity. For this, SrCO₃, Sr_0.5Ca_0.5CO₃, and CaCO₃ nanoparticles were precipitated using Na₂CO₃, SrCl₂, and/or CaCl₂ as precursors. Their morphology and crystallinity were evaluated by electron microscopy (SEM) and X-ray diffraction, respectively. The nanoparticles were added to a poly (vinyl alcohol) gel and used to brush dentin surfaces isolated from human third molars. Dentin chemical composition before and after brushing was investigated by infrared spectroscopy (FTIR) and X-ray dispersive energy spectroscopy. Dentin tubule morphology, obliteration, and resistance of the coatings to acid attack were investigated by SEM and EDS. The cytotoxicity and ability of the particles to trigger the mineralization of hDPSCs in vitro were studied. Dentin brushed with the nanoparticles was coated by a mineral layer that was also able to penetrate the tubules, while CaCO₃ remained as individual particles on the surface. FTIR bands related to carbonate groups were intensified after brushing with either SrCO₃ or Sr_0.5Ca_0.5CO₃. The shift of the phosphate-related FTIR band to a lower wavenumber indicated that strontium replaced calcium on the dentin structure after treatment. The coating promoted by SrCO₃ or Sr_0.5Ca_0.5CO₃ resisted the acid attack, while calcium and phosphorus were removed from the top of the dentin surface. The nanoparticles were not toxic to hDPSCs and elicited mineralization of the cells, as revealed by increased mineral nodule formation and enhanced expression of COL1, ALP, and RUNX2. Adding Sr_0.5Ca_0.5CO₃ as an active ingredient in dentifrices formulations may be commercially advantageous since this compound combines the well-known abrasive properties of calcium carbonate with the mineralization ability of strontium, while the final cost remains between the cost of CaCO₃ and SrCO₃. The novel Sr_0.5Ca_0.5CO₃ nanoparticles might emerge as an alternative for the treatment of dental hypersensitivity.

The objective of this study is to evaluate, in vitro, the microleakage of bacteria of 3 different implant connections for a period of 14 days. 60 dental implants (AoN) (n = 20) were distinguished into three groups, accordingly to the type of connection: External Hexagon (EH), Internal Hexagon (IH), and Cone Morse (CM) connection. All implants were inserted and fixed on sterile special vinyl support. Ten fixtures for each group were inoculated in the internal platform with 1.0 μL of Streptococcus oralis (SO) and the other ten with the same amount of Pseudomonas aeruginosa (PA). The penetration of bacterial suspension into the surrounding solution was determined by the observation of the turbidity of the broth. Five implants for each sub-group were randomly observed at SEM, to verify the correct fitting of the abutments. Considering the total of the samples analyzed, CM showed significantly lower bacterial contamination, with respect to IH. In particular, bacterial contamination was found in 45%, 55%, and 20% of EH, IH, and CM, respectively. Analyzing results for the type of inoculated bacteria, P. aeruginosa showed a higher ability to contaminate all the connections, with respect to S. oralis.

This work aimed to evaluate and compare the antimicrobial actions and effects over time of eight types of mouthwash, based on the impact of chlorhexidine on the main microorganisms that are responsible for oral diseases: Enterococcus faecalis, Pseudomonas aeruginosa, and Candida albicans. The mouthwashes’ antimicrobial action was determined in terms of their minimum inhibitory concentration (MIC), minimum bactericidal/fungicidal concentration (MBC/MFC), and time-kill curves at different contact times (10 s, 30 s, 60 s, 5 min, 15 min, 30 min, and 60 min), against selected oral microorganisms. All the mouthwashes showed a notable effect against C. albicans (MICs ranging from 0.02% to 0.09%), and higher MIC values were recorded with P. aeruginosa (1.56% to >50%). In general, the mouthwashes showed similar antimicrobial effects at reduced contact times (10, 30, and 60 s) against all the tested microorganisms, except with P. aeruginosa, for which the most significant effect was observed with a long time (15, 30, and 60 min). The results demonstrate significant differences in the antimicrobial actions of the tested mouthwashes, although all contained chlorhexidine and most of them also contained cetylpyridinium chloride. The relevant antimicrobial effects of all the tested mouthwashes, and those with the best higher antimicrobial action, were recorded by A—GUM^® PAROEX^®A and B—GUM^® PAROEX^®, considering their effects against the resistant microorganisms and their MIC values.

The present study aims to discuss the main factors involving the use of 5-aminolevulinic acid together with red LED light and its application in endodontic treatment through a narrative review and a case report. Persistence of microorganisms remaining on chemical-mechanical preparation or intracanal dressing is reported as the leading cause of failure in endodontics. Photodynamic therapy has become a promising antimicrobial strategy as an aid to endodontic treatment. Being easy and quick to apply, it can be used both in a single session and in several sessions, as well as not allowing forms of microbial resistance. 5-aminolevulinic acid in combination with red LED light has recently been studied in many branches of medicine, with good results against numerous types of bacteria including Enterococuss faecalis. The case report showed how bacterial count of CFU decreased by half (210 CFU/mL), after 45 min of irrigation with a gel containing 5% of 5-aminolevulinic acid compared to the sample before irrigation (420 CFU/mL). The subsequent irradiation of red LED light for 7 min, the bacterial count was equal to 0. Thus, it is concluded that the use of 5-aminolevulinic acid together with red LED light is effective in endodontic treatment.

The interaction between oral bacteria and dental implant surfaces is a critical factor in the success and longevity of dental implants. With advancements in additive manufacturing technologies, selective laser melting (SLM) has emerged as a prominent method for producing titanium implants with highly controlled microstructures and porosities. These 3D printed titanium surfaces offer significant benefits, such as enhanced osseointegration and improved mechanical properties. However, the same surface features that promote bone cell attachment and proliferation may also provide favorable conditions for bacterial adhesion and biofilm formation. Understanding the dynamics of these interactions is essential for developing implant surfaces that can effectively resist bacterial colonization while promoting tissue integration. This narrative review explores the complex interplay between oral bacteria and SLM-produced titanium porous surfaces, examining current research findings and potential strategies for optimizing implant design to mitigate the risks of infection and ensure successful clinical outcomes.