ABSTRACT
This study aimed to compare the quality of root canal obturation (ratio of area occupied by gutta-percha (G), sealer (S), and presence of voids (V)) in different anatomical irregularities (intercanal communications, lateral irregularities, and accessory canals) located at different thirds of the root canal system of mandibular molar replicas. Sixty-seven 3D printed replicas of an accessed mandibular molar were prepared using ProGlider and ProTaper Gold rotatory systems. Three specimens were randomly selected to be used as controls and did not receive further treatment. The rest were randomly distributed in 4 experimental groups to be obturated using either cold lateral compaction (LC), continuous wave of condensation (CW), and core-carrier obturation (ThermafilPlus (TH) or GuttaCore (GC)) (n=16 per group). AHPlus® sealer was used in all groups. The three controls and a specimen from each experimental group were scanned using micro-computed tomography. The rest of the replicas were sectioned at the sites of anatomical irregularities and examined at 30× magnification. The G, S, and V ratios were calculated dividing the area occupied with each element by the total root canal area and then compared among groups using the Kruskal-Wallis test. Voids were present in all obturation techniques with ratios from 0.01 to 0.15. CW obtained a significantly higher G ratio in the irregularity located in the coronal third (0.882) than LC (0.681), TH (0.773), and GC (0.801) (p<0.05). TH and GC achieved significantly higher G ratios in those located in the apical third (p<0.05). The worst quality of obturation was observed in the loop accessory canal with all obturation techniques. Whitin the limitations of this study, it can be concluded that CW and core-carrier obturation are respectively the most effective techniques for obturating anatomical irregularities located in the coronal and the apical third.
Subject(s)
Dental Pulp Cavity , Gutta-Percha , Materials Testing , Root Canal Filling Materials , Root Canal Obturation , X-Ray Microtomography , Root Canal Obturation/methods , Root Canal Filling Materials/chemistry , X-Ray Microtomography/methods , Gutta-Percha/chemistry , Dental Pulp Cavity/anatomy & histology , Dental Pulp Cavity/diagnostic imaging , Humans , Reproducibility of Results , Reference Values , Molar/anatomy & histology , Epoxy Resins/chemistry , Printing, Three-Dimensional , Surface Properties , Statistics, Nonparametric , Random AllocationABSTRACT
Abstract This study aimed to compare the quality of root canal obturation (ratio of area occupied by gutta-percha (G), sealer (S), and presence of voids (V)) in different anatomical irregularities (intercanal communications, lateral irregularities, and accessory canals) located at different thirds of the root canal system of mandibular molar replicas. Sixty-seven 3D printed replicas of an accessed mandibular molar were prepared using ProGlider and ProTaper Gold rotatory systems. Three specimens were randomly selected to be used as controls and did not receive further treatment. The rest were randomly distributed in 4 experimental groups to be obturated using either cold lateral compaction (LC), continuous wave of condensation (CW), and core-carrier obturation (ThermafilPlus (TH) or GuttaCore (GC)) (n=16 per group). AHPlus® sealer was used in all groups. The three controls and a specimen from each experimental group were scanned using micro-computed tomography. The rest of the replicas were sectioned at the sites of anatomical irregularities and examined at 30× magnification. The G, S, and V ratios were calculated dividing the area occupied with each element by the total root canal area and then compared among groups using the Kruskal-Wallis test. Voids were present in all obturation techniques with ratios from 0.01 to 0.15. CW obtained a significantly higher G ratio in the irregularity located in the coronal third (0.882) than LC (0.681), TH (0.773), and GC (0.801) (p<0.05). TH and GC achieved significantly higher G ratios in those located in the apical third (p<0.05). The worst quality of obturation was observed in the loop accessory canal with all obturation techniques. Whitin the limitations of this study, it can be concluded that CW and core-carrier obturation are respectively the most effective techniques for obturating anatomical irregularities located in the coronal and the apical third.
ABSTRACT
The dental pulp can be affected by thermal, physical, chemical, and bacterial phenomena that stimulate the inflammatory response. The pulp tissue produces an immunological, cellular, and vascular reaction in an attempt to defend itself and resolve the affected tissue. The expression of different microRNAs during pulp inflammation has been previously documented. MicroRNAs (miRNAs) are endogenous small molecules involved in the transcription of genes that regulate the immune system and the inflammatory response. They are present in cellular and physiological functions, as well as in the pathogenesis of human diseases, becoming potential biomarkers for diagnosis, prognosis, monitoring, and safety. Previous studies have evidenced the different roles played by miRNAs in proinflammatory, anti-inflammatory, and immunological phenomena in the dental pulp, highlighting specific key functions of pulp pathology. This systematized review aims to provide an understanding of the role of the different microRNAs detected in the pulp and their effects on the expression of the different target genes that are involved during pulp inflammation.
Subject(s)
Dental Pulp/metabolism , Gene Expression Regulation , Inflammation/genetics , MicroRNAs/genetics , Up-Regulation , Cell Differentiation/genetics , Dental Pulp/pathology , Down-Regulation , Humans , Inflammation/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism , Signal Transduction/geneticsABSTRACT
OBJECTIVES: The purpose of this study was the creation and validation of an instrument to evaluate adherence to occupational health protocols used in dentistry that arise from official regulations and international recommendations on infection control, biosafety, and occupational health in dentistry. Additionally, in May 2017 the effectiveness of the instrument was documented within the dental care clinics in the postgraduate area. METHODS: The instrument was developed based on constructs of occupational health, infection control, and biosafety in dentistry, made up of 21 indicators of 5 dimensions called protocols. Using direct observation through 35 measurements during 1 week, adherence to occupational health protocols was evaluated in postgraduate residents within the clinical sections of endodontics/pediatric dentistry, periodontics, prosthodontics, and orthodontics. RESULTS: The instrument presents an index of 0.88 in Cronbach's alpha analysis. There is a 34.4% adherence within the postgraduate dental clinic to the proposed occupational health protocols. The protocol with the highest adherence at 41.1% was the personal protection protocol. The periodontics section had a 52.9% observance of the proposed protocols and had the highest adherence to occupational health protocols. CONCLUSIONS: The proposed instrument is valid and reliable to evaluate adherence to the proposed occupational health protocols within dental care clinics. Dental clinics must be inspected and evaluated to ensure adherence to infection control, biosafety, and occupational health protocols within routine dental practice.