Comparação entre soluções irrigadoras na endodontia: clorexidina x hipoclorito de sodio

The objective of this review was reporting an overview about the properties of two irrigating solutions, solution of sodium hypochlorite and chlorhexidine, used in the treatment of root canals. A solution must submit irrigating antimicrobial action, dissolve waste tissue, promote wetting to facilitate the instrumentation, and present biocompatibility with the adjacent tissues. The sodium hypochlorite used in different concentrations has been the solution of choice among professionals by presenting antimicrobial action and act as a solvent tissue. However, today, chlorhexidine has been widely used as an irrigating solution due to specific properties that enable its use, such as substantivity, antimicrobial effectiveness, and low toxicity. Thus the solution of chlorhexidine with different concentrations is presented as an alternative to irrigating solution for the treatment of root canals.

Avaliação da alteração dimensional de modelos obtidos a partir de moldagens com alginato tradicional e outro com desinfetante

The present study aims at evaluating dimensional alteration of stone casts made from impressions with a standard irreversible hydrocolloid and an antimicrobial one. For this, an alginate without disinfectant (Type II Jeltrate) and other containing chlorhexidine (Type II Avagel) were used, which rose by the same regime of treatment: without disinfection; immersion; and spraying. A 1% sodium hypochlorite solution was used for 10 minutes. To obtain the impressions, a perforated impression tray was made from a standard metal model. After molding, the molds were washed in running water for 30 seconds to simulate removal of saliva. Then, with the exception of the control group, these molds were subjected to disinfection treatment. After 10 minutes they were washed again. 60 samples poured with type V special gypsum (Durone) were obtained, that were measured 3 times in a stereomicroscope (SZX12, Olympus) to record the average of dimensional alterations. The disinfection treatment did not bring significant changes in the models obtained from both alginate tested (standard p = 0.7102; with chlorhexidine p = 0.5832). The results showed a statistically significant and additional advantage of the traditional alginate on alginate with chlorhexidine, with respect to dimensional alteration (p < 0.05).

Effects of coronal leakage on concentration of hydrogen ions and calcium hydroxide release of several calcium hydroxide pastes over different periods of time

Purpose: To evaluate the effects of coronal leakage on concentration of hydrogen ions (pH) and calcium release of several calcium hydroxide pastes, over different periods of time. Material and Methods: Fifty extracted human mandibular central incisors (n=10) were instrumented up to the F2 instrument and assigned to the following intracanal dressing: G1- Calen, G2- Calen with 0.4% chlorhexidine (CHX), G3- Calcium hydroxide with camphorated paramonochlorophenol (CPMC) and glycerin, G4- Calen, but temporary filling material maintained during all test (positive control) and G5- Root canal without intracanal dressing (negative control). All groups were immersed in distilled water for 7 days. In sequence, the temporary filling materials were removed, except in controls groups. All specimens were individually mounted on a specific device and only its root again immersed in distilled water. Concentration of hydrogen ions and calcium release by calcium hydroxide pastes in distilled water were evaluated in 24h, 7, 14 and 28 days. The results were submitted to ANOVA test (p = 0.05). After 28 days, root canals from experimental groups were examined in SEM. Results: G1, G2, G3 and G4 presented similar pH values and calcium release and did not differ from each other (p>0.05), up to 7 days. After this time G1, G2 and G3 presented values lower values than G4 (p<0.05). In SEM analysis, calcium hydroxide residues were observed in all experimental groups. Conclusions: After 7 days, coronal leakage decreased the concentration of hydrogen ions and calcium ion release provided by all calcium hydroxide pastes.

Avaliação in vitro do pH do hidróxido de cálcio usado como medicação intracanal em associação com clorexidina e racealfatocoferol

Objective: The aim of this study was to evaluate the pH of calcium hydroxide (CalenTM) when associated or not with chlorhexidine 0.4%, and when associated with chlorhexidine with the addition of 20% or 10% of alphatocopherol (AchéTM), assessed in several periods of time. Methods: Fourty dentine tubes 20 mm, properly standardized, were made from bovine anterior teeth roots. Following, a perforation was achieved in the roots distal face at 7 mm from the cervical radicular line by using a #1/2 carbide bur. After complete root sealing is made, except in the perforation local, the radicular canals were filled with one of the following associations: Group I – Calen®; Group II – Calen™ with chlorehxidine at 0.4%; Group III – Calen™ with chlorhexidine at 0.4% with the addition of 20% (weight) of alhatocopherol compound and Group IV – Calen™ with chlorhexidine at 0.4% with the addition of 10% (weight) alphatocopherol. After cervical sealing is accomplished, the roots were immersed in water MiliQ and the pH, assessed in 24h, 7, 14, 21, 28 and 45 days. Results and Conclusion: In all periods tested, the pH of the calcium hydroxide (Calen™) was similar to the pH of the calcium hydroxide (Calen™) associated with chlorhexidine 0.4% and 10% alphatocopherol (p > 0.05). The association of 20% alphatocopherol obtained the pH lower than the association with 10% (p < 0.05). The pH of the association with chlorhexidine was similar to the pure calcium hydrocide (Calen™) after the 14th day (p > 0.05) only. Therefore, on the 45th day, this difference was significant again (p < 0.05).

Antimicrobial activity of root canal irrigants associated with cetrimide against biofilm and planktonic Enterococcus Faecalis

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Marginal adaptation of Class V restorations with current generation dentin-bonding agents: effect of different dentin surface treatments.

This study sought to assess the use of chlorhexidine with several excipients as a dentin surface treatment and its effect on marginal adaptation of class V restorations with current-generation dentin bonding agents. A total of 120 human third molars were selected and allocated into 12 groups, with standardized buccal class V restorations randomly divided into preconditioned dentin rinsed with: water; water + chlorhexidine; ethanol; or ethanol + chlorhexidine. After rinsing of dentin (previously conditioned with 35% phosphoric acid) with the test solutions, the Adper single bond 2, prime and bond 2.1, and Excite bonding systems were applied randomly. Restorations were performed with FiltekTM Z350 XT composite resin. The resulting specimens were subjected to thermal and mechanical load cycling. Quantitative analysis of marginal adaptation was performed on epoxy replicas by means of scanning electron microscopy. Results were assessed by means of the Kruskal-Wallis test (percentages of continuous margins) and Wilcoxon test (differences between percentages of continuous margins before and after thermal cycling and mechanical loading), at a significance level of p < 0.05. Outcomes in the chlorhexidine-treated groups were not superior to those obtained with other treatments.

Effects of Er, Cr:YSGG laser irradiation on external adaptation of restorations in caries-affected cavities

This study evaluated the effect of Er,Cr:YSGG laser irradiation on the external adaptation of composite resin restorations in caries-affected cavities. Mixed class V cavity preparations were performed in 36 intact human third molars, in half of which caries was artificially induced. Both healthy and carious dentin were etched with 35% phosphoric acid (Ultradent Products Inc., South Jordan, Utah, USA), and the teeth were divided into three groups, i.e., (a) untreated etched dentin, (b) application of the Er, Cr:YSGG laser and (c) use of chlorhexidine as an adjunct in the bonding process. Restorations were fabricated with Z350 XT FiltekTM composite resin (3M ESPE) and subsequently the specimens were subjected to thermocycling to simulate artificial ageing. Quantitative analysis of external adaptation was performed by scanning electron microscopy in both healthy and affected dentin using epoxy resin replicas. It was concluded that the application of laser and chlorhexidine did not affect the percentages of marginal adaptation of class V restorations. Furthermore, thermocycling may influence adaptation values.

Residues of different gel formulations on dentinal walls: a SEM/EDS analysis

The aim of this study was to evaluate the presence of residues of sodium hypo-chlorite gel, chlorhexidine gel, and EDTA gel on dentina l walls after canal preparat ion throughchemical SEM- elemental chemical microanal ys is (EDS) analysis. Forty-eight single-rootedteeth were selected. They had their crowns sectioned and were instrumented with a reciprocat-ing system. The canals were irrigated with 5 mL of saline solution during root canal preparation.After instrumentation, the root canals were irrigated with 3 mL 17% EDTA followed by 1 min ofultrasonic passive activation (33 20 sec) to remove the smear layer, and then irrigated with3 mL of saline solution. The specimens were randomized into three groups (n 5 12) accord ing tothe chemical substance that filled the root canal for 30 min: GI: 5.5% sodium hypochlorite gel;GII: 2% chlorhexidine gel; GIII: 24% EDTA gel; Negative c ontrol group: no substance was used.Then, the root canals were irrigated with 6 mL of saline solution followed by 1 min of ultrasonicpassive activation (33 20 sec). After ultrasonic activation , the canals were irrigated with 2 mLsaline. The roots were sect ioned, and the perce ntage of each chemical element present in thesamples was analyzed through chemi cal SEM-EDS microanalysis. All expe rimental groupsshowed a significantly higher percentage of chemical elements (Na and/or Cl) than the controlgroup (P < 0.03). This in vitro study has shown that, regardless of chemical solutions used evenafter the final irrigation protocol, chemical residues of d ifferent substances remained attached tothe r oot c anal wa lls. Microsc. Res. Tech. 78:495–49 9, 2015.

In vitro study of staining agents effects on optical properties of esthetic restorative materials

The authors have studied the effect of four staining agents on the optical properties of esthetic restorative materials through translucency tests. Two commercial brands of composite resins were used: Point 4 (Kerr) and Charisma (Heraeus-Kulzer). The liquids tested were: wine, cola, chlorhexidine solution and nicotine solution. The translucency was measured at different periods of time: P0 – before immersion (baseline), P1 - 1 h after immersion, P2 - 2 h after immersion and successively, P3 – 24 h after immersion up to a period of 7 weeks. ANOVA statistical analysis was applied to the data (p < 0.05). The results lead to the following conclusions: (1) Composite resins submitted to the tested immersion mediums were stained, (2) the lower percentage of translucency was observed for nicotine containing solution, (3) The percentage of translucency decreased with the period of immersion.

Atividade antimicrobiana de enxaguatórios bucais sem álcool à base de clorexidina sobre candida albicans

The aim of this study was to evaluate the antimicrobial activity of alcohol-free mouthwashes on Candida albicans. Twenty clinical isolates of C. albicans and one reference strain (ATCC 18804) were evaluated after exposure to two 0.12% chlorhexidine-based and alcohol-free (“Ca” and “Or”) in comparison to gluconate chlorhexidine with ethanol (positive control). The maximum inhibitory dilution (MID) and maximum fugal dilution (MFD) were determined by the microdilution method. Twelve serial dilutions (from 50 to 0.02%) were prepared in duplicate. Then, 100 µL of C. albicans suspension (106 cells.mL–1) were added to the wells. After incubation (37 °C/24 hours), MID was determined by reading the optical density. For MFD determination, the content of the wells were plated on Saouraud agar. For MID, there were no differences between groups Or and control, but Ca group showed a MID statistically higher (Kruskal-Wallis, p = 0.0012). For MFD, there were no differences between Ca and control (Mann-Whitney test, p = 0.1631). It can be concluded that Ca group showed a fungicid activity against C. albicans similar to the control, but lower fungistatic activity when compared to the control. Group Or showed only a fungistatic action similar to control.

Eradication of a Mature Methicillin-Resistant Staphylococcus aureus (MRSA) Biofilm From Acrylic Surfaces

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Impact of chemical agents for surface treatments on microhardness and flexural strength of root dentin

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Propriedades físico-química e antibacteriana de medicações intracanal a base de hidróxido de cálcio e óxido de zinco micro e nanoparticulados

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Efeito da água ozonizada e gluconato de clorexidina sobre propriedades mecânicas e microbiológicas de materiais utilizados para confecção de próteses odontológicas

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Effect of the addition of antimicrobial agents on shore a hardness and roughness of soft lining materials

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)