RESUMEN
OBJECTIVES: This study was performed to evaluate the effect of blood contamination on the compressive strength (CS) of Root MTA (RMTA) modified with Calcium chloride (CaCl2) and Disodium hydrogen phosphate (Na2HPO4) as setting accelerators over time. MATERIALS AND METHODS: A total of 110 cylindrical specimens of RMTA were divided into 6 experimental groups as follows: Group1, RMTA; Group 2, RMTA modified with CaCl2 (RMTA-C); Group 3, RMTA modified with Na2HPO4 (RMTA-N); Group 4, RMTA contaminated with blood; Group 5, RMTA-C contaminated with blood; Group 6, RMTA-N contaminated with blood. The CS of specimens in all groups was evaluated after 3 hr, 24 hr, and 1 wk. In the modified groups (groups 2, 3, 5, and 6) the CS of five specimens per group was also evaluated after 1 hr. RESULTS: Blood contamination significantly reduced the CS of all materials at all time intervals (p < 0.05). After 3 hr, the CS of specimens in the RMTA groups (with and without blood contamination) was significantly lower than those in the RMTA-C and RMTA-N groups (p < 0.05). The CS values were not significantly different at the other time intervals. In all groups, the CS of specimens significantly increased over time (p < 0.05). CONCLUSIONS: Blood contamination decreased the CS of both original and accelerated RMTA.
RESUMEN
INTRODUCTION: Endodontic treatment of immature necrotic teeth is challenging. Recently a biologically based treatment called regenerative endodontic treatment was introduced. Although regenerative endodontic treatment causes root development, there are several drawbacks and unfavorable outcomes that should be addressed. This article describes regenerative endodontic treatment of 2 maxillary central incisors with poor root development outcomes. METHODS: A healthy 14-year-old female patient was referred. The patient had history of an impact trauma 6 years before the first visit. Clinical and radiographic examinations revealed that maxillary central incisors were immature and necrotic with symptomatic apical periodontitis. After local anesthesia, rubber dam isolation, and access cavity preparation each tooth was irrigated with 20 mL of NaOCl 5.25% and received triple antibiotic dressing (ciprofloxacin, metronidazole, minocycline) for 4 weeks. In the next visit, after eliminating antibiotic dressing, bleeding was induced inside the canals, and then the coronal thirds of the canals were sealed with mineral trioxide aggregate. A week later, both teeth were permanently restored. RESULTS: In clinical and radiographic follow-ups, both teeth were functional, periapical lesions were healed, and the apices formed. However, the roots were not developed. After 6 years, because of moderate discoloration and caries, both teeth received root canal therapy and were permanently restored with casting dowel core and full crown restorations. CONCLUSIONS: Criteria for case selection in regenerative endodontic treatments should be determined.