ABSTRACT
INTRODUCTION: Understanding the physicochemical and biological properties of endodontic sealers is important for endodontic treatment planning. This study evaluated the properties of EndoSequence BC Sealer HiFlow (BCH; Brasseler USA, Savannah, GA), EndoSequence BC Sealer (BC, Brasseler USA), and AH Plus (AHP; Dentsply DeTrey, Konstanz, Germany). The effect of temperature on the setting time and flow of these sealers was also evaluated. METHODS: The setting time, flow, radiopacity, pH, solubility, and calcium release were investigated following ISO guidelines. The morphology and chemical composition of the sealers were evaluated by scanning electron microscopy and energy-dispersive spectroscopy. The antibacterial activity of sealers was tested against 2 strains of Enterococcus faecalis. Sealer cytotoxicity and the effects on messenger RNA expression of proinflammatory and mineralization genes were also investigated. Data analysis was performed using analysis of variance, Tukey, Kruskal-Wallis, and Dunn multiple comparison tests. P ≤ .05 was considered statistically significant. RESULTS: The setting time and flow rate of all sealers were affected by heat (P ≤ .05). The setting times and solubility of BCH and BC were significantly higher than AHP (P ≤ .0001). The radiopacity of AHP was higher than BCH and BC (P ≤ .0001). All sealers were alkaline and had antibacterial effects. Cell viability was higher for BCH and BC than AHP (P ≤ .0001). No significant differences in messenger RNA expression of proinflammatory and mineralization genes were observed. CONCLUSIONS: Overall, BCH and BC had similar physicochemical and biological properties. The observed high solubility of BCH and BC as well as the high cytotoxicity of AHP might negatively impact the clinical performance of these materials. The application of heat affected the setting time and flow of all sealers.
Subject(s)
Calcium Phosphates , Oxides , Root Canal Filling Materials , Silicates , Drug Combinations , Germany , Humans , Materials Testing , Root Canal Filling Materials/chemistryABSTRACT
STATEMENT OF PROBLEM: Excess cement around dental implants is a significant cause of peri-implant inflammation. Research has focused on approaches to cement removal, the type of cement used, and the different instruments used for cement removal with titanium abutments. However, data comparing zirconia with titanium abutments are lacking. PURPOSE: The purpose of this in vitro study was to compare the effectiveness of excess cement removal from zirconia and titanium custom abutments using an explorer and to compare the effects of cement removal on the abutment surfaces. MATERIAL AND METHODS: Implant analogs were placed in a cast in the position of the 2 maxillary central incisors. After creating similar emergence profiles for both the implant abutments, 18 zirconia and titanium custom abutments were fabricated with 1-mm subgingival finish lines on the facial and interproximal areas and an equigingival finish line on the palatal side. The crowns were cemented with zinc oxide-eugenol cement, and a steel explorer was used to remove the excess cement. All abutments were analyzed under a scanning electron microscope for cement remnants and scratches. RESULTS: The mean surface area of cement remnants on the zirconia abutments was 778 ±113 µm2, and for titanium abutments, it was 1123 ±252 µm2, which in terms of the mean percentage area was 3.27% of the total surface area of zirconia and 4.71% of titanium abutments. Only a few abutments from each group showed scratches, and no deep scratches or gouges were observed. CONCLUSIONS: Zirconia and titanium abutments had statistically similar cement remnants. Scratches were observed on only a few specimens.
