Assessment of Bond Integrity, Durability, and Degree of Conversion of a Calcium Fluoride Reinforced Dentin Adhesive

Fluoride-Induced Mitochondrial Dysfunction and Approaches for Its Intervention

Fluoride is present everywhere in nature. The primary way that individuals are exposed to fluoride is by drinking water. It's interesting to note that while low fluoride levels are good for bone and tooth growth, prolonged fluoride exposure is bad for human health. Additionally, preclinical studies link oxidative stress, inflammation, and programmed cell death to fluoride toxicity. Moreover, mitochondria play a crucial role in the production of reactive oxygen species (ROS). On the other hand, little is known about fluoride's impact on mitophagy, biogenesis, and mitochondrial dynamics. These actions control the growth, composition, and organisation of mitochondria, and the purification of mitochondrial DNA helps to inhibit the production of reactive oxygen species and the release of cytochrome c, which enables cells to survive the effects of fluoride poisoning. In this review, we discuss the different pathways involved in mitochondrial toxicity and dysfunction induced by fluoride. For therapeutic approaches, we discussed different phytochemical and pharmacological agents which reduce the toxicity of fluoride via maintained by imbalanced cellular processes, mitochondrial dynamics, and scavenging the ROS.

Development of a Boron Nitride-Filled Dental Adhesive System

There is a dearth of adhesive systems capable of forming stable bonds between restorative materials and tooth surfaces. To address the concern, this study determined the effects of using methacrylate-functionalized boron nitride nanosheets (BNNSs) in a polymeric dental adhesive system. The bisphenol A glycidyl dimethacrylate (BisGMA):2 hydroxyethyl methacrylate (HEMA) (60:40) adhesive monomer blend with a photoinitiator was filled with 0 wt% (control), 0.1 wt%, and 1 wt% BNNSs and light cured. Fourier transform infrared spectroscopy was performed to determine the conversion degree of monomer double bonds (DoC). Water absorption and solubility were measured. Flexural strength and Youngs's modulus were evaluated to determine the mechanical properties of the composite adhesive system. Finally, dentin bond strength degradation and fracture mode were quantified with a microtensile bond test to confirm the bonding ability of the developed adhesive system. Results showed that the incorporation of BNNSs increased DoC (9.8% and 5.4% for 0.1 and 1 wt%, respectively), but it did not affect water sorption (101.9-119.72 (µg/mm3)), solubility (2.62-5.54 (µg/mm3)), Young's modulus (529.1-1716.1 MPa), or microtensile bond strength (46.66-54.72 MPa). Further studies are needed with varying BNNS loading percentages from 0.1 wt% to 1 wt% in order to more comprehensively determine the effect of BNNSs on dental adhesives.

Assessing the Cleanliness of Dental Implants Using Scanning Electron Microscopy and Energy-Dispersive X-ray Spectroscopy Analysis-A SEM and EDS In Vitro Study

A wide variety of titanium (Ti) alloy dental implant systems are available and as a result, choosing the correct system has become a challenge. Cleanliness of the dental implant surface affects osseointegration but surface cleanliness may be jeopardized during manufacturing. The purpose of this study was to assess the cleanliness of three implant systems. Fifteen implants per system were examined with scanning electron microscopy to identify and count foreign particles. Particle chemical composition analysis was performed with energy-dispersive X-ray spectroscopy. Particles were categorized according to size and location. Particles on the outer and inner threads were quantitatively compared. A second scan was performed after exposing the implants to room air for 10 min. Carbon, among other elements, was found on the surface of all implant groups. Zimmer Biomet dental implants had higher particle numbers than other brands. Cortex and Keystone dental implants showed similar distribution patterns. The outer surface had higher particle numbers. Cortex dental implants were the cleanest. The change in particle numbers after exposure was not significant (p > 0.05). Conclusion: Most of the implants studied were contaminated. Particle distribution patterns vary with the manufacturer. The wider and outer areas of the implant have a higher probability of contamination.

Effect of Fluoride on Cytotoxicity Involved in Mitochondrial Dysfunction: A Review of Mechanism

Fluoride is commonly found in the soil and water environment and may act as chronic poison. A large amount of fluoride deposition causes serious harm to the ecological environment and human health. Mitochondrial dysfunction is a shared feature of fluorosis, and numerous studies reported this phenomenon in different model systems. More and more evidence shows that the functions of mitochondria play an extremely influential role in the organs and tissues after fluorosis. Fluoride invades into cells and mainly damages mitochondria, resulting in decreased activity of mitochondrial related enzymes, weakening of protein expression, damage of respiratory chain, excessive fission, disturbance of fusion, disorder of calcium regulation, resulting in the decrease of intracellular ATP and the accumulation of Reactive oxygen species. At the same time, the decrease of mitochondrial membrane potential leads to the release of Cyt c, causing a series of caspase cascade reactions and resulting in apoptosis. This article mainly reviews the mechanism of cytotoxicity related to mitochondrial dysfunction after fluorosis. A series of mitochondrial dysfunction caused by fluorosis, such as mitochondrial dynamics, mitochondrial Reactive oxygen species, mitochondrial fission, mitochondrial respiratory chain, mitochondrial autophagy apoptosis, mitochondrial fusion disturbance, mitochondrial calcium regulation are emphasized, and the mechanism of the effect of fluoride on cytotoxicity related to mitochondrial dysfunction are further explored.