Depth of cure of bulk-fill flowable composite resins.

In recent years, manufacturers have introduced flowable composite resins that reportedly can be placed in increments of 4 mm or greater. The purpose of this study was to evaluate the depth of cure of bulk-fill flowable composite resins (SureFil SDR Flow, Grandio Flow, and Venus Bulk Fill) and a conventional flowable composite resin (Revolution Formula 2). Depth of cure was measured in terms of bottom-maximum Knoop hardness number (KHN) ratios and the International Organization for Standardization (ISO) 4049 scrape technique. Shades A2 and A3 of SureFil SDR Flow, Grandio Flow, and Revolution Formula 2 were tested. Venus Bulk Fill was tested in its only available shade (universal). Specimens in thicknesses of 2, 3, 4, 5, and 6 mm were polymerized for 20 or 40 seconds, and a hardness tester was used to determine the hardness ratios for each shade at each thickness. For the scraping technique, after specimens were exposed to the curing light, unpolymerized composite resin was removed with a plastic instrument, the polymerized composite was measured, and the length was divided by 2 per ISO guidelines. According to the KHN ratios and the scrape test, Venus Bulk Fill predictably exceeded the manufacturer's claim of a 4-mm depth of cure at both 20 and 40 seconds of curing time. The overall results for depth of cure showed that Venus Bulk Fill ≥ SureFil SDR Flow ≥ Grandio Flow ≥ Revolution Formula 2.

The rate of adverse events during IV conscious sedation.

Conscious sedation has become an integral part of dentistry; it is often used to reduce anxiety or fear in some patients during oral surgery, periodontal surgery, implant placement, and general dentistry procedures. The purpose of this study was to evaluate the frequency of adverse events during IV conscious sedation provided by credentialed general dentists and periodontists in the United States Air Force (USAF). Sedation clinical records (Air Force Form 1417) from calendar year 2009 were requested from all USAF bases. A total of 1,468 records were reviewed and 19 adverse events were noted in 17 patients. IV complication (infiltration) was the most common adverse event. The overall adverse event rate was 1.3 per 100 patients treated. The results of this study show that moderate sedation provided by general dentists and periodontists in the USAF has a low incidence of adverse events, and conscious sedation remains a viable option for providers for the reduction of anxiety in select patients.

Higher-concentration carbamide peroxide effects on surface roughness of composites.

BACKGROUND: Ten percent carbamide peroxide has been used extensively within the dental profession for the purpose of bleaching teeth. Although this method has been successful, the use of higher-concentration carbamide peroxides (20-35%) for home bleaching has increased substantially in the past few years. The purpose of this study was to evaluate changes in surface roughness of a hybrid and a microfilled composite after exposure to bleaching agents containing higher concentrations of carbamide peroxide. MATERIALS AND METHODS: Sixty-eight circular, resin-based composite specimens (8 mm x 2 mm) were prepared against a Mylar surface. Half of the specimens were fabricated from a hybrid composite material and the other half with a microfilled composite. Specimens were polished with aluminum oxide finishing disks, divided into four groups, and then exposed either to 20% carbamide peroxide for 3 hours per day for 14 days or to 35% carbamide peroxide for 1 hour per day for 14 days. The mean surface roughness (Ra) was determined for each specimen before and after exposure to bleaching agents, using mechanical profilometry. Data were analyzed by two-way analysis of variance (ANOVA) for differences between composite type, carbamide peroxide concentrations, and interaction of the two factors with respect to average surface roughness. All data analysis was performed at alpha = 0.05. RESULTS: Mean change from baseline of surface roughness (Ra) of microfilled composite and 20% carbamide peroxide was -0.03 microm +/- 0.10 microm; microfilled composite and 35% carbamide peroxide: 0.01 microm x 0.02 microm; hybrid composite and 20% carbamide peroxide: -0.43 microm x 0.91 microm; hybrid composite and 35% carbamide peroxide: -0.19 microm x 0.43 microm. Surface roughness of hybrid or microfilled composite did not change significantly from baseline with either concentration of carbamide peroxide (p = .300). CLINICAL SIGNIFICANCE: Higher-concentration carbamide peroxide bleaching agents, used as intended by the manufacturer, pose no significant risk to resin composite restoration surfaces.