Enamel permeability and resistance to acid challenges after systemic use of sodium alendronate: a study in rat teeth.

Objectives: To evaluate the enamel resistance and permeability of rat teeth to acid challenges after systemic use of sodium alendronate.

Materials And Methods: Eighteen Wistar rats (36 teeth), aged 36-42 days (200-230 g), were assigned into two groups: alendronate group (n = 20 teeth), which received two weekly doses of 1 mg/kg of alendronate, via gavage; and a non-alendronate group (n = 16 teeth), which received only distilled water. After 60 days, the animals were killed, the maxillary incisors were extracted and used for the artificial induction of the caries lesion (pH cycling regimen) and erosion area (immersion cycles in cola-type soft drink) and for the enamel permeability test (dye penetration).

The combined use of Er,Cr:YSGG laser and fluoride to prevent root dentin demineralization.

Unlabelled: The use of erbium lasers to prevent caries in enamel has shown positive results. However, it is not known if Er,Cr:YSGG laser can also be used to increase acid resistance of root dentine, which is another dental tissue susceptible to the action of cariogenic bacteria.

Objective: To analyze the effects of the Er,Cr:YSGG laser (λ=2.

Effect of pretreatment with an Er:YAG laser and fluoride on the prevention of dental enamel erosion.

The aim of this study was to evaluate the effect of the Er:YAG laser and its association with fluoride (1.23% acidulate phosphate fluoride gel) on the prevention of enamel erosion. Sixty specimens were obtained from bovine enamel (4 × 4 mm), which were ground flat, polished, and randomly divided into five groups according to the preventive treatments: control-fluoride application; L--Er:YAG laser; L+F--laser + fluoride; F+L--fluoride + laser; L/F--laser/fluoride simultaneously.

Nd:YAG laser in occlusal caries prevention of primary teeth: a randomized clinical trial.

Dental caries is still the most prevalent chronic disease affecting human populations. Among the preventive treatments performed, it has been reported that laser irradiation combined with topical fluoride can induce an even greater increase in enamel caries resistance. The aim of this study was to evaluate the Nd:YAG laser, with or without fluoride, in occlusal caries prevention of the primary dentition.

The use of an Er:YAG laser to remove demineralized dentin and its influence on dentin permeability.

The purpose of this study was to analyze, correlate, and compare the demineralization and permeability of dentin remaining after caries removal with either an Er:YAG laser, a bur, or a curette. Thirty human dentin fragments were immersed in a demineralizing solution for 20 days and were randomly divided into three groups (n = 10) for the removal of the demineralized lesion. The groups were G1-Er:YAG laser (200 mJ/6 Hz; noncontact at 12 mm; spot: 0.

Effect of Nd:YAG laser combined with fluoride on the prevention of primary tooth enamel demineralization.

Most studies dealing with the caries preventive action of Nd:YAG laser have been done in permanent teeth and studies on primary teeth are still lacking. The aim of this study was to evaluate in vitro the effect of Nd:YAG laser combined or not with fluoride sources on the acid resistance of primary tooth enamel after artificial caries induction by assessing longitudinal microhardness and demineralization depth. Sixty enamel blocks obtained from the buccal/lingual surface of exfoliated human primary molars were coated with nail polish/wax, leaving only a 9 mm² area exposed on the outer enamel surface, and randomly assigned to 6 groups (n=10) according to the type of treatment: C-control (no treatment); APF: 1.

Effect of a bleaching agent on abrasion of resin-based restoratives.

Purpose: To evaluate the effect of a 10% carbamide peroxide-containing bleaching agent on brushing abrasion of esthetic restorative materials.

Methods: Using a randomized complete block design, 150 specimens (n = 15) measuring 3 x 3 x 2 mm were fabricated into acrylic resin cylinders, using one of the restorative materials: a microfilled resin composite (Al), a hybrid resin composite (Ch), a flowable resin composite (Wa), a resin-modified glass-ionomer cement (Fj) and a polyacid-modified resin composite (Dy). The bleaching agent or artificial saliva (control) was applied for 2 hours/day.

Effect of a 10% carbamide peroxide on wear resistance of enamel and dentine: in situ study.

Objectives: This triple-blind, 2x2 crossover in situ study, was undertaken to verify whether the wear resistance of enamel and root dentine would be affected by bleaching with a 10% carbamide peroxide agent and a placebo agent.

Methods: Thirty slabs of each substrate (2mm x 3mm x 2mm) were selected for each phase, after flattening and polishing procedures and microhardness test. After a 7-day lead-in period, one specimen of each substrate was randomly bonded on the facial surface of each one of 30 subject's upper second premolars.

Bleaching agents with varying concentrations of carbamide and/or hydrogen peroxides: effect on dental microhardness and roughness.

Purpose: To evaluate the effect of low and highly concentrated bleaching agents on microhardness and surface roughness of bovine enamel and root dentin.

Methods: According to a randomized complete block design, 100 specimens of each substrate were assigned into five groups to be treated with bleaching agents containing carbamide peroxide (CP) at 10% (CP10); hydrogen peroxide (HP) at 7.5% (HP7.

Susceptibility of bleached enamel and root dentin to artificially formed caries-like lesions.

Purpose: To evaluate in vitro the susceptibility of caries-like lesion formation on enamel and root dentin that had been bleached with carbamide peroxide agents.

Methods: 150 slabs of bovine enamel and root dentin were ground flat and polished. According to a randomized complete block design, the specimens were then allocated to be bleached with agents (Rembrandt) containing 12% [CP12], 16% [CP16], 22% [CP22] or 30% [CP30] of carbamide peroxide over 21 days.

Concentration-dependent effect of bleaching agents on microhardness and roughness of enamel and dentin.

Purpose: To evaluate the microhardness and surface roughness of enamel and root dentin bleached with 10%, 15% and 22% carbamide peroxide agents.

Methods: 52 slabs of enamel and root dentin (6 x 3 x 2 mm) were cut from bovine incisors, ground flat and polished. According to a randomized complete block design, enamel and root dentin slabs (n = 13) were independently allocated to be bleached with one of the following carbamide peroxide-containing agents (CP): 10% (Rembrandt Bleaching Gel Plus), 15% (Rembrandt Xtra Comfort), or 22% (Rembrandt Xtra Comfort Ultra Strength).