Evaluation of Fluoride Release in Chitosan-Modified Glass Ionomer Cements.

OBJECTIVE: This study assessed the influence of chitosan nanoparticles on the fluoride-releasing ability of 4 glass ionomer cement (GIC) through an in vitro analysis. METHODS: Four types of GIC (type II light cure universal restorative, type II universal restorative, GC Fuji VII, and type IX) were modified with nanochitosan particles; 10% chitosan was added to the glass ionomer liquid. Six specimens for each of the 4 groups were created, using expendable Teflon moulds. Discs of each type of GIC (n = 6) were immersed in deionised water at various time intervals. Electrodes selective for fluoride ions were employed to analyse the amount of released fluoride at 1, 7, 14, 21, and 28 days. RESULTS: Chitosan-modified GICs showed greater fluoride release than conventional GICs at all time points. All samples showed an initial high release of fluoride that tapered off with time. The total amount of fluoride released increased from the 1st day to the 28th day on adding chitosan to all the 4 types of GIC. Amongst those, type IX high-strength posterior extra with chitosan released a considerably higher quantity of fluoride at all time intervals. CONCLUSIONS: In all the experimental groups, adding chitosan to the glass ionomer liquid had an accelerating effect on its fluoride-releasing property.

Independent and confluent middle mesial root canals in mandibular first molars: a report of four cases.

Mandibular molars demonstrate considerable variations with respect to number of roots and root canals. The possibility of additional root canals should be considered even in teeth with a low frequency of abnormal root canal anatomy. This paper discusses the endodontic management of the rare anatomical complexity middle mesial canals in mandibular first molar and also serves to remind the clinicians that such anatomical variations should be taken into account during the endodontic treatment of the mandibular molars.

Evaluation of the antibacterial and physical properties of glass ionomer cements containing chlorhexidine and cetrimide: an in-vitro study.

BACKGROUND: Incorporation of antibacterial agents frequently results in changes in the physical properties of restorative materials. MATERIALS AND METHODS: This in-vitro study investigated the antibacterial and physical properties of Glass ionomer cement (GIC) with chlorhexidine and cetrimide, to determine the optimal concentration, for incorporation of these agents to obtain antibacterial GICs for use with the Atraumatic restorative treatment approach. This was assessed using the agar diffusion test. Chlorhexidine diacetate and cetrimide were added to Glass ionomer cement type-IX (GIC-FUJI IX) at 1 and 2% W/W ratio. The experimental GIC specimens were placed on agar plates inoculated with Lactobacillus casei, and the area of inhibition was calculated after 48 hours. RESULTS: All the experimental GICs exhibited inhibition of bacteria, but the sizes were dependent on the concentration of the antibacterial agent. Incorporation of chlorhexidine diacetate and cetrimide, at 2%, significantly decreased the compressive strength, and the setting time was extended a little by the addition of any concentration of chlorhexidine and cetrimide. CONCLUSIONS: The present study demonstrated that experimental GICs containing chlorhexidine diacetate and cetrimide were effective in inhibiting bacteria associated with caries, and incorporation of 1% cetrimide was optimal to give the appropriate antibacterial and physical properties.

Spiral CT diagnosis and endodontic management of an anatomically variant palatal root with two canals in a maxillary first molar.

This case report presents the endodontic management of an anatomically variant palatal root with 2 canals (Vertucci type II) in a maxillary first molar, which was confirmed with the help of spiral computed tomography (SCT). This serves to remind clinicians that such anatomic variations should be taken into account during the endodontic treatment of maxillary molars and highlights the invaluable aid of the SCT in accurate diagnosis and in negotiating the complex morphologic variations in root canals, thus enabling successful endodontic management.

Antifungal efficacy of 5.25% sodium hypochlorite, 2% chlorhexidine gluconate, and 17% EDTA with and without an antifungal agent.

INTRODUCTION: The aim of this in vitro study was to evaluate the efficacy of 5.25% sodium hypochlorite (NaOCl), 2% chlorhexidine gluconate (CHX), and 17% EDTA as a final irrigant with and without the inclusion of an antifungal agent (1% clotrimazole) on Candida albicans. METHODS: Sixty-five single-rooted instrumented and inoculated with a suspension of C. albicans. The experimental specimens were divided into two groups. The irrigant group was divided into three subgroups and irrigated with 5.25% NaOCl, 2% CHX, and 17% EDTA, respectively. The irrigant with antifungal group was divided into three subgroups and irrigated with 5.25% NaOCl, 2% CHX, and 17% EDTA respectively followed by 1% clotrimazole. Aliquots from the experimental teeth were plated on 4% Sabouraud agar (Tital Biotech, Delhi, India), and the colony-forming units (CFUs) were evaluated under light microscopy (400x). RESULTS: NaOCl, 5.25%, exhibited superior antifungal efficacy compared with 2% CHX and 17% EDTA (p < 0.001). On inclusion of 1% clotrimazole, there was a significant decrease in the CFU (p < 0.001); 5.25% NaOCl and 2% CHX with clotrimazole showed significantly greater antifungal properties than 17% EDTA with clotrimazole (p < 0.001). CONCLUSION: One percent of clotrimazole proved to be effective against C. albicans when used along with root canal irrigants as a final rinse.

Comparative evaluation of the surface tension and the pH of calcium hydroxide mixed with five different vehicles: an in vitro study.

AIM: The aim of this study was to evaluate the surface tension and pH of five different vehicles that are used as potential agents to mix calcium hydroxide in root canal treatments and to compare them with the final surface tension and pH of calcium hydroxide mixed with these vehicles. MATERIALS AND METHODS: The study was carried out in two phases. In Phase I, the surface tension and pH of five vehicles (distilled water, saline, anesthetic solution, chlorhexidine, and glycerin) were evaluated using a Du Nuoy Tensiometer and a pH Meter. In Phase II, a predetermined amount of calcium hydroxide was mixed with the individual vehicles and the surface tension and pH was determined. In each group, seven samples were evaluated. RESULTS: Among the individual vehicles, chlorhexidine had the least surface tension values (39.8+1.1 dynes/cm). Among the various calcium hydroxide mixtures, calcium hydroxide with chlorhexidine showed the least surface tension values (36.4+1.1 dynes/cm). All the vehicles showed an acidic pH ranging from 5 to 6.5. There was a significant increase in the pH values with the addition of calcium hydroxide to the respective vehicles. The calcium hydroxide mixtures had an alkaline pH ranging from 9 to 11.5; the highest pH was observed for calcium hydroxide mixed with distilled water and saline (11.5+0.2). CONCLUSION: The surface tension and pH of the vehicles directly influenced the surface tension and pH of the calcium hydroxide mixtures. Chlorhexidine was found to be a better vehicle for calcium hydroxide when used as an intracanal medicament.

Influence of deep dry cryogenic treatment on cutting efficiency and wear resistance of nickel-titanium rotary endodontic instruments.

This study tested the effect of cryogenic treatment on nickel-titanium (NiTi) endodontic instruments. Ten rotary NiTi instruments (ProFile 30, 0.06; Dentsply Maillefer Instruments SA, Baillegues, Switzerland)) were subjected to deep dry cryogenic treatment at liquid nitrogen temperature (-185 degrees C) (group A) and compared with that of nontreated instruments (group B). Root canals of 30 extracted permanent mandibular premolars were prepared to size 25 using ProFile 0.04 taper rotary NiTi instruments. Each instrument was used in 4 root canals for a total of 240 seconds. Cutting efficiency in rotary motion was assessed from weight loss of tooth samples after instrumentation. Wear resistance was assessed from surface defects on cutting heads pre- and postinstrumentation using scanning electron microscope. The weight loss was significantly higher in group A (p < 0.05, Student t test). The presence of surface defects after use was higher in group B. Deep dry cryogenic treatment increases the cutting efficiency significantly but not the wear resistance.