ABSTRACT
The purpose of this systematic review was (a) to search for clinical articles pertaining to success and failure of nonsurgical root canal therapy, and (b) to assign levels of evidence to these studies. Electronic and manual searches were conducted to identify studies published between January 1966 and September 2004 with information on the success and failure of nonsurgical root canal therapy. Articles were reviewed and graded for strength of level of evidence (LOE) from one (highest level) to five (lowest level). This review resulted in the identification of 306 clinical studies related to this topic area. Six articles were randomized controlled trials (RCTs, LOE 1). This search also identified 12 low-quality RCTs (LOE 2), 14 cohort studies (LOE 2), five case-control and eight cross sectional studies (LOE 3), four low-quality cohort studies (LOE 4), and five low-quality case-control studies (LOE 4). The majority (73) of the often-quoted "success and failure" studies were case series (LOE 4). The rest of the articles were descriptive epidemiological studies (42), case reports (114), expert opinions (18), literature reviews (4), and one meta-analysis. Based on these findings, it appears that a few high-level studies have been published in the past four decades related to the success and failure of nonsurgical root canal therapy. The data generated by this search can be used in future studies to specifically answer questions and test hypotheses relevant to the outcome of nonsurgical root canal treatment.
Subject(s)
Root Canal Therapy/methods , Case-Control Studies , Cohort Studies , Evidence-Based Medicine , Humans , Randomized Controlled Trials as Topic , Research Design , Treatment OutcomeABSTRACT
The purpose of this study was to compare the effect of MTAD (a mixture of a tetracycline isomer [doxycycline], an acid [citric acid], and a detergent [Tween 80]) and phosphoric acid on the bond strength to enamel and dentin using a conventional OptiBond Solo Plus dentin adhesive system. One hundred flat surfaces (50 enamel/50 dentin) were prepared for bonding. Specimens were embedded in acrylic with the flat surface exposed. One of the following surface treatments was applied before bonding composite with Optibond Solo Plus (Kerr Corp): 1 min NaOCl/1 min EDTA; 1 min NaOCl/1 min MTAD; 30 s etch with H3PO4 (positive control), 2 min saline (negative control), or 20 min NaOCl/5 min MTAD (clinical protocol for MTAD). Shear bond strength was tested 30 min after bonding. Data were analyzed using a one-way ANOVA followed by the Student-Newman-Keuls multiple comparison method. Surface pretreatment with acid etch resulted in the greatest enamel bond strengths (p < 0.05). All surface pretreatments were superior to saline for dentinal bonding (p < 0.05). On the basis of our findings, it appears that teeth endodontically treated with the MTAD protocol for clinical use (20 min 1.3% NaOCl/5 min MTAD) may not need any additional dentin conditioning before the application of the dental adhesive.
Subject(s)
Citric Acid , Dental Etching/methods , Doxycycline , Polysorbates , Root Canal Irrigants , Analysis of Variance , Dental Enamel , Dental Stress Analysis , Dentin , Dentin-Bonding Agents , Humans , Materials Testing , Phosphoric Acids , Resin Cements , Shear Strength , Statistics, NonparametricABSTRACT
The purpose of this study was to evaluate the effect of MTAD on the flexural strength and modulus of elasticity of dentin. Dentin bars were randomly assigned to eight groups treated with various concentrations of NaOCl (5.25%, 2.65%, 1.31%, 0.66%), 17% EDTA, MTAD, saline, or according to a clinical protocol with 1.3% NaOCl and then 5 min of MTAD. Specimens were subjected to flexural strength and modulus of elasticity tests. Two-sample t test (alpha = 0.05) showed no statistically significant differences between various groups except for a reduction in flexural strength for the 2-h MTAD group (p = 0.002) and the EDTA group (p = 0.002). A significant reduction of modulus of elasticity for the 2-h MTAD group (p < 0.001), EDTA group (p < 0.001), and 0.6% NaOCl (p < 0.002) also was noted. There was no significant difference in flexural strength and modulus of elasticity between the dentin bars exposed to saline or MTAD when applied according to the clinical protocol (p > 0.05). These results indicate that MTAD can be used as prescribed for clinical use without affecting the physical properties of the dentin.
