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

Abstract

Our study aimed to synthesize and compare the mechanical properties and dentin interaction of two adhesives; experimental adhesive (EA) and EA containing 5 wt.% calcium fluoride (CaF2) nano-crystals (CaF2 adhesive-CAFA). CaF2 nano-crystals were synthesized by reacting two solutions (containing calcium and fluoride) in a glass chamber using a heated air system. The EA was produced using a mix of monomers, photo-initiators, camphorquinone, and electron initiators. The synthesized CaF2 nano-crystals were centrifuged to guarantee that inside the adhesive there is homogenized dispersion of the filler particles. Their integration in the EA yielded two groups; Gp-1: EA (without CaF2, control) and Gp-2: (5 wt.% CaF2 containing adhesive, CAFA). Sixty teeth were prepared and set to form bonded specimens using the two adhesives. The CaF2 nano-crystals were irregularly shaped with an average particle size of 30–200 nm. The highest μTBS values were obtained for CAFA-non-thermocycled (NTC) samples (32.63 ± 3.15), followed by EA-NTC (31.80 ± 3.75) specimens. On thermocycling (TC), both adhesive groups presented lower μTBS values (CAFA-TC: 29.47 ± 3.33 and EA-TC: 24.04 ± 3.69). Hybrid layer (HL) formation and resin tags of varying depths were perceived for both adhesive groups. The EDX analysis demonstrated the presence of carbon (C), silica (Si), calcium (Ca), and fluoride (F) for CAFA group. Micro-Raman spectroscopy revealed distinct peaks for CaF2 nano-crystals. The CAFA group presented the greatest DC. The addition of CaF2 nano-crystals in the adhesive caused improved bond μTBS and DC. The incorporation also demonstrated suitable dentin interaction, depicted by appropriate HL and resin tag development.

Development of a Boron Nitride-Filled Dental Adhesive System

“…The study clearly showed that addition of BNNS fillers has increased the DoC significantly, which is highly desirable for any adhesive system. Polymers 2023, 15, x FOR PEER REVIEW 6 of 14 fluoride-nanofiller-added sample had a higher DoC (61.54 ± 4.07) in comparison to the control (56.8 ± 5.5) [51]. The study clearly showed that addition of BNNS fillers has increased the DoC significantly, which is highly desirable for any adhesive system.…”

“…In a similar study, Degrazia et al (2017) showed that with an increase in the addition of boron nitride nanotubes, the DoC increased until 0.1% (87.97 ± 1.65% for control and 91.74 ± 0.43% for 0.1% sample), but the addition of 0.15% of the nanotubes decreased the DoC (89.54 ± 1.29%) [1]. Similarly, in another study, AlRefeai et al (2021) showed that the calcium-fluoride-nanofiller-added sample had a higher DoC (61.54 ± 4.07) in comparison to the control (56.8 ± 5.5) [51]. The study clearly showed that addition of BNNS fillers has increased the DoC significantly, which is highly desirable for any adhesive system.…”

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

“…Various compositional analysis methods are available on the market. In this study, SEM with a built-in EDS was used due to the simplicity and reliability of this combination as a multimethod for detecting, assessing, and compositional analysis, either to suspected contamination on implants as in the current study or to other devices and materials used in the dental field [ 19 , 36 , 38 ]. The EDX analysis revealed that almost every implant has carbon residuals on the surface, findings that agree with most studies [ 19 ].…”

“…EDX is a standard method frequently used in dental research to analyze the elemental compositions in organic and inorganic material samples [ 5 , 14 , 25 , 30 , 36 , 37 , 38 , 39 ]. An electron beam projects toward the sample‘s surface, excites it, and causes the emission of variable X-ray photons; an energy-dispersive X-ray spectroscopy detector (EDS) identifies the distinctive energy of each element [ 40 ].…”

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

“…A large number of literature have shown that F and Ca have a strong affinity. Supplementary Ca forms a novel complex, insoluble CaF 2 , in the intestine by combining with F, which reduces the absorption and toxicity of fluoride ( 51 ). However, a large amount of serum calcium into bone tissue will lead to increasing bone mineral density, hyperosteogeny, hypocalcemia.…”