Discoloration of teeth due to different intracanal medicaments

OBJECTIVES: The objective of this study was to assess coronal discoloration induced by the following intracanal medicaments: calcium hydroxide (CH), a mixture of CH paste and chlorhexidine gel (CH/CHX), and triple antibiotic paste (3Mix). MATERIALS AND METHODS: Seventy extracted single-canal teeth were selected. Access cavities were prepared and each canal was instrumented with a rotary ProTaper system. The specimens were randomly assigned to CH, CH/CHX, and 3Mix paste experimental groups (n = 20 each) or a control group (n = 10). Each experimental group was randomly divided into 2 subgroups (A and B). In subgroup A, medicaments were only applied to the root canals, while in subgroup B, the root canals were completely filled with medicaments and a cotton pellet dipped in medicament was also placed in the pulp chamber. Spectrophotometric readings were obtained from the mid-buccal surface of the tooth crowns immediately after placing the medicaments (T1) and at 1 week (T2), 1 month (T3), and 3 months (T4) after filling. The ∆E was then calculated. Data were analyzed using 2-way analysis of variance (ANOVA), 3-way ANOVA, and the Scheffé post hoc test. RESULTS: The greatest color change (ΔE) was observed at 3 months (p < 0.0001) and in 3Mix subgroup B (p = 0.0057). No significant color change occurred in the CH (p = 0.7865) or CH/CHX (p = 0.1367) groups over time, but the 3Mix group showed a significant ΔE (p = 0.0164). CONCLUSION: Intracanal medicaments may induce tooth discoloration. Use of 3Mix must be short and it must be carefully applied only to the root canals; the access cavity should be thoroughly cleaned afterwards.

Antibacterial effect of calcium hydroxide on intraluminal and intratubular Enterococcus faecalis

Root canal treatment involves the elimination of intraradicular microorganisms. Calcium hydroxide [Ca[OH]2] is the most widely used canal dressing material. Enterococcus faecalis [E. faecalis] has been reported to be resistant to Ca[OH]2 in-vivo. The purpose of this study was to evaluate the efficacy of Ca[OH]2 on the elimination of intraluminal and intratubular E. faecalis. Thirty six human single-rooted teeth were contaminated with E. faecalis. Thirty specimens in the experimental group were treated with 10% Ca[OH]2; six specimens were treated with normal saline as the positive control [n=6]. Specimens from experimental group were randomly divided into two subgroups of 15 each. In subgroup A, specimens were incubated and sampled after one day and in subgroup B, they were tested at day seven. Paper points and Gates Glidden burs were used to obtain the intraluminal and intratubular E. faecalis respectively. Samples obtained from these root canal preparations were analyzed for bacterial load by counting the number of colony forming units [CFUs]. Mann-Whitney and t-test were used for analysis. Group B had significant decrease in CFUs compared with group A with both sampling methods [P<0.001]. No differences were observed between the antimicrobial properties of Ca[OH]2 against intraluminal and intratubular E. faecalis. After 1 week, there was a significant reduction in CFU load with Ca[OH]2 intra canal medication. Ca[OH]2 showed the same antimicrobial efficacy on intraluminal and intratubular E. faecalis

effect of blood on apical microleakage of Epiphany and AH26: an in vitro study

Blood contamination of the canal during preparation can be a major problem in endodontics; this may result in apical microleakage. The aim of this in vitro study was to evaluate the effect of blood on apical microleakage of a resin-based root canal sealer [AH26] and a polymer-based root canal sealer [Epiphany].In this experimental study, 50 decoronated' central incisors and canine teeth were prepared by RaCe rotary system and randomly divided into 4 groups [n=10]. Groups A[1] and A[2] were obturated by Epiphany/Resilon and AH26/Gutta-percha, respectively. The obturations were performed with a single cone technique after drying root canals. In B[1] and B[2] groups, the test groups, 0.02cc citrated human blood was injected into dried root canals and they were obturated in the same manner. Ten specimens were served as positive and negative controls [n=5].The apical leakage was measured by means of a computerized fluid filtration method after 1 day and 3 weeks. The data was analyzed by One-Sample Kolmogorov-Smirnov, Independent Sample t-test and univariate analysis. Statistical significances were preset at a=0.05. There was no significant difference in apical microleakage of the two sealers after 1 day and 3 weeks in dry and blood environment [P>0.05]. Sealer and environment had no interaction [P>0.05]. Blood contamination has no significant effect on the apical microleakage of Epiphny and AH26