ABSTRACT
AIM: The purpose of this study is to evaluate and compare the incidence of dentinal defects after root canal shaping using rotary nickel-titanium (Ni-Ti) instruments (ProTaper Gold [PTG] and ProTaper Next [PTN]) and reciprocating instrument (WaveOne Gold [WOG]). MATERIALS AND METHODS: One hundred human mandibular premolars with single root and single canal with canal curvature <10° were randomly divided into five groups (n = 20 teeth per group). The root canals were instrumented using hand K-files (positive control), full sequence rotary files PTG and PTN, and reciprocating single-file system WOG. One group was left unprepared and served as negative control. Roots were sectioned horizontally at 3, 6, and 9 mm from the apex and evaluated under a stereomicroscope. RESULTS: PTG, WOG, and PTN showed dentinal defects in 40%, 53.3%and 30% of the samples, respectively. CONCLUSION: Irrespective of motion kinematics, dentinal defects are observed in all the Ni-Ti file groups. Within the limitations of the present study and the available literature, incidence of dentinal defects is less with instruments working in continuous rotation rather than instruments with reciprocating motion.
ABSTRACT
BACKGROUND: Root canal (RC) treatment is most common and effective method for treatment of diseases related to periapical area and pulp of teeth. With the increase in age, the formation of secondary dentin, calcification of canals, and reduction of medullary cavity volume, it becomes increasingly difficult to accomplish a perfect RC treatment, hence the understanding of RC variation and changes in variation with increasing age improves the success rates. AIM: The aim of this study was to study the RC variation in the age-group of 10-14 years and to find if the gradual increase in age plays a role in increasing the complexity of RC variation. MATERIALS AND METHODS: This study was carried out in Government Medical College, Patna, Bihar, India, from January 2018 to April 2019. Subjects within the age range of 10-14 years were selected conferring to predetermined inclusion and exclusion criteria. The subjects were divided into the groups according to age-Group I: 10-11 years, Group II: 11-12 years, Group III: 12-13 years, and Group IV: 13-14 years. The subjects were further divided into Group A and B according to sex to study if there is any significant difference in RC variation. Three intraoral periapical (IOPA) radiography with radiovisiography (RVG) of each subject were taken from three different predetermined angles and these IOPAs were then analyzed by three independent observers and the most agreed on value was included. The IOPAs were analyzed for the number of roots, the number of canals in each root and the variation of each RC were classified according to Vertucci's Classification. RESULTS: The most common T of RC variation in mesial root of mandibular first molar was T IV succeeded by T II and T I. For distal canal of mandibular first molar, the most common variation was T I, followed by T II and T III. In our study we found that 98.88% of mandibular molars were having two roots. No significant difference was found in the variation of canal according to age or sex in our study. CONCLUSION: Hence, we conclude that no significant difference is seen in RC variation according to sex and age. As the groups we included in our study were not wide apart enough in age, a further long-term study is needed to ascertain if the complexity of RC increases with age.
