SUMMARY: This study evaluated the effect of 2% chlorhexidine digluconate (CHX) used as a therapeutic primer on the long-term bond strengths of two etch-and-rinse adhesives to normal (ND) and caries-affected (CAD) dentin. Forty extracted human molars with coronal carious lesions, surrounded by normal dentin, were selected for this study. The flat surfaces of two types of dentin (ND and CAD) were prepared with a water-cooled high-speed diamond disc, then acid-etched, rinsed and air-dried. In the control groups, the dentin was re-hydrated with distilled water, blot-dried and bonded with a three-step (Scotchbond Multi-Purpose-MP) or two-step (Single Bond 2-SB) etch-and-rinse adhesive. In the experimental groups, the dentin was re-hydrated with 2% CHX (60 seconds), blot-dried and bonded with the same adhesives. Resin composite build-ups were made. The specimens were prepared for microtensile bond testing in accordance with the non-trimming technique, then tested either immediately or after six-months storage in artificial saliva. The data were analyzed by ANOVA/Bonferroni tests (α=0.05). CHX did not affect the immediate bond strength to ND or CAD (p>0.05). CHX treatment significantly lowered the loss of bond strength after six months as seen in the control bonds for ND (p0.05). The application of MP on CHX-treated ND or CAD produced bonds that did not change over six months of storage.
SUMMARY: This study evaluated the effect of different light energy densities on conversion degree (CD) and Knoop hardness number (KHN) of RelyX ARC (RLX) resin cement. After manipulation according to the manufacturer's instructions, RLX was inserted into a rubber mold (0.8 mm X 5 mm) and covered with a Mylar strip. The tip of the light-curing unit (LCU) was positioned in contact with the Mylar surface. Quartz-tungsten-halogen (QTH) and light-emitting diode (LED) LCUs with light densities of 10, 20 and 30 J/cm2 were used to light-cure the specimens. After light curing, the specimens were stored dry in lightproof containers at 37°C. After 24 hours, the CD was analyzed by FT-Raman and, after an additional 24-hours, samples were submitted to Knoop hardness testing. The data of the CD (%) and KHN were submitted to two-way ANOVA and the Tukey's test (α=0.05). QTH and LED were effective light curing units. For QTH, there were no differences among the light energy densities for CD or KHN. For LED, there was a significant reduction in CD with the light energy density set at 10 J/cm2. KHN was not influenced by the light-curing unit and by its light energy density.
The aim of this study was to present a case report of the surgical removal of hyperplasia in the oral cavity, using carbon dioxide (CO2) laser radiation and rehabilitation with a complete denture. Epulis fissuratum occurs in complete denture patients, because a constant irritative action induces the mucosa to grow under poorly fitting dentures. These lesions must be removed, and to avoid a relapse, new complete dentures should be made to maintain healthy surgical tissues. The clinical sequence presented in this case shows a completely edentulous patient with epulis fissuratum on the lower alveolar ridge extending to the vestibular sulcus of the anterior region of mandible. Immediate complete dentures were made prior to the lesion removal with CO2 laser radiation, providing satisfactory results in oral function and tissue health.
Bonding to different dental restorative materials is challenging. This study aimed to evaluate the effect of a 10-MDP-based dentin adhesive on the shear bond strength (SBS) of self-adhesive resin cement (RC) to implant abutment materials. One hundred and twenty specimens were obtained from zirconia (ZO), cobalt-chromium alloy (CoCr), and commercially pure titanium (Ti), which were treated as follows (n = 10): control group—non-treated (CG), 10-MDP-based dentin adhesive (SB), light-cured SB (SB-LC), and zirconia primer (ZP). Blocks of RC were buildup and, after 24 h, were tested for bond strength. Data of SBS (MPa) were submitted to two-way ANOVA and Tukey test (α = 0.05). There was no difference in SBS among materials for CG and ZP, higher SBS were recorded for Ti SB and Ti SB-LC compared to ZO upon the same surface treatments. For the comparisons among treatments, SB-LC showed the highest SBS for CoCr. For ZO and Ti, higher SBS were recorded with SB and SB-LC. No cohesive failures were observed. It was concluded that the surface treatment with 10-MDP-based materials increased the bond strength of the resin cement to abutment materials, which showed to be material dependent.
Objective: The aim of this study was to assess the profiles of dental students at the ICT/CSJC-UNESP School of Dentistry and their preferred studying style preferences. Materials and methods: Data on age, sex, place of residence, first-choice course, secondary education background and study method preference were collected from an online questionnaire given in the second year dental materials course (first class) of the day and evening courses of the years 2016 to 2019. All data were tabulated and submitted to one-way ANOVA and to t test, both with ? = 0.05. Results: Most of the students were women living in São José dos Campos city who had chosen Dentistry as their first-choice course. Many were originally from other cities and lived in shared accommodation with friends. The majority stated that private high school was their main educational background. Conclusions: Although ICT/CSJC-UNESP students were from millennial and post-millennial generations, they preferred studying alone and in silence rather than studying in groups.