Root and canal morphology of the maxillary second premolars as indicated by cone beam computed tomography.

The aim was to evaluate the morphology of maxillary second premolars. The root canal configurations were classified according to Vertucci and a new system by Ahmed et al. based on CBCT images. In addition, the number of roots and the level where they bifurcated were identified, and morphological measurements were performed based on anatomical landmarks. Single-rooted forms were most common. Bifurcation occurred most often in the middle part of the root. The most common canal configuration was type I according to Vertucci and code 1 SP1 according to the new classification. The measurements showing the results were as follows (mm): palatal cusp/buccal cusp/the lowest point of the occlusal surface to pulp chamber ceiling 6.18/6.54/4.77; the ceiling of the pulp chamber was found at the CEJ in 92.28% of the specimens. The maxillary second premolars tended to be single-rooted and with one root canal.

Root form and canal anatomy of maxillary first premolars: a cone-beam computed tomography study.

The aim of this study was to evaluate the root and canal morphology of permanent maxillary first premolars in a Polish population using cone-beam computed tomography scanning (CBCT) and to compare the classifications by Vertucci and Ahmed et al. Images of 350 maxillary first premolars were analyzed. Scans were obtained from 226 patients: 131 women and 95 men. The root canal configurations were classified according to Vertucci and a new system by Ahmed et al. In addition, the number of roots and the level where roots bifurcated were identified. The results were submitted to statistical analysis. Most maxillary first premolars had two roots (69.1%). Most bifurcations were located in the coronal part of the root (44.2%) and the least in the apical part (15.3%). Bifurcation in the coronal part of the root was observed more often in the teeth of men than women. In turn, bifurcation in the central or apical part was significantly more common in women than in men. The most common canal configuration of the maxillary first premolars was type IV (78.2%) according to Vertucci and 2FPB1P1 (65.4%) according to the new classification. Among the remaining cases, almost all types of canals described by Vertucci, and many combinations of codes given in the new classification were demonstrated. The maxillary first premolars displayed a wide range of root and canal anatomical variations. The new system for classifying canal morphology based on Ahmed et al. is more accurate than the Vertucci classification.

Clinical aspects of pulp stones: A case report series.

Pulp stones (PSs) are calcified masses that can be found in the pulp cavity of any deciduous or permanent tooth. They can be observed in healthy, diseased, and even unerupted or impacted teeth. Calcifications within the pulp may lead to a poorer outcome of a root canal procedure, as they can block access to the root canals, and hinder their subsequent cleaning and shaping. The paper describes 4 clinical cases of denticles located in the coronal and radicular pulp. Therapeutic methods of PS removal with different techniques and instruments are discussed. Specialist root canal treatment (RCT) was performed in aseptic conditions with the use of long-shank rose-head burs and an endodontic ultrasonic device under the magnification of a dental operative microscope (OM). During endodontic treatment, all PSs were totally removed, which allowed the further preparation, and finally obturation of the canal system. The use of modern diagnostic and therapeutic methods - three-dimensional (3D) diagnostic radiology, endodontic techniques, such as ultrasounds used during the removal of PSs and the irrigation of the canals, and the thermoplastic methods of canal obturation - can provide good results of treatment of this pathology. The removal of PSs from the pulp cavity is a complex and difficult procedure, requiring skill, dexterity, and appropriate equipment and facilities. The clinical approach introduced in this paper allows endodontists to avoid potential complications like perforation, the unnecessary removal of hard tissues or the weakening of the tooth structure.

The influence of the manufacturing process of rotary files on the shaping of L-shaped canals.

BACKGROUND: The nickel-titanium alloy used in the production of nickel-titanium files contains approx. 56% nickel and 44% titanium by weight. To improve the properties of nickel-titanium files, the manufacturers introduce some innovations in the production process. Their purpose is primarily to decrease the stiffness of the instruments while increasing the resistance to cyclic fatigue, which reduces the risk of file separation. One of the most popular processes is the heat treatment of the nickel-titanium alloy. OBJECTIVES: The aim of the research was to determine the influence of the manufacturing process of rotary files on the shaping of L-shaped canals. MATERIAL AND METHODS: Fifty L-shaped resin canals were instrumented (10/group) with ProTaper Universal ®, ProTaper Next®, Hyflex CM®, Hyflex EDM®, or WaveOne Gold® files, with the same apical size of 25. Each L-shaped resin canal was photographed both before and after instrumentation. Differences between the change of the working length and apical transportation were analyzed statistically. RESULTS: The smallest mean loss of the working length was observed after instrumentation with Hyflex CM files. Statistically significant differences in the working length were found between ProTaper Universal and Hyflex CM (p = 0.0032), ProTaper Universal and Hyflex EDM (p = 0.021), and ProTaper Universal and WaveOne Gold (p = 0.0112) files. The lowest apical transportation was noted in the case of WaveOne Gold files. In terms of apical transportation, statistically significant differences were observed between ProTaper Universal and WaveOne Gold files (p = 0.0254). Shaping Lshaped canals with the ProTaper Universal file system resulted in the greatest changes in the working length (x = 0.35 mm) and apical transportation (x = 0.034 mm). CONCLUSIONS: The study, with its limitations, shows that in the files whose nickel-titanium alloy was subjected to a thermal treatment process, a smaller loss of the working length and lower values of apical transportation were observed.

The morphology of maxillary first and second molars analyzed by cone-beam computed tomography in a polish population.

BACKGROUND: The success of endodontic treatment is greatly affected by the location of the root canals. The purpose of this study was to evaluate the root and canal morphology of permanent maxillary first and second molars in a Polish population using cone-beam computed tomography scanning. METHODS: Cone-beam computed tomography (CBCT) scans of maxillary first and second molars the maxilla were examined. The number of roots and root canals, and the frequency of additional canals (MB2) in the mesiobuccal root canals were determined. The results were subjected to statistical analysis using the chi-square test or the chi-square test with Yates' correction. RESULTS: A total of 112 CBCT images of maxillary first (n = 185) and second molars (n = 207) from 112 patients were analyzed. All the maxillary first molars had three roots (100%). The majority of maxillary second molars had three roots (91.8%), 5.8% had two roots and 2.4% had one root. A statistically significant difference was observed between the numbers of roots in the maxillary first and second molars (p < 0.01). A statistically significant difference was also found in the distribution of the number of canals in the maxillary first and second molars (p < 0.001). The majority of maxillary first molars had four root canals (59.5%), while 40.5% had three root canals. Most maxillary second molars had three root canals (70%). Additional canals (MB2) in the mesiobuccal roots were detected significantly more frequently in the maxillary first molars than the second molars (p = 0.000) and more frequently in men than in women (p < 0.05). A higher prevalence of two canals in the mesiobuccal roots in maxillary second molars occurred in patients aged between 31 and 40 years than in patients aged between 21 and 30 years. In the maxillary first molars, the prevalence of the MB2 canal in the mesiobuccal root was almost equally distributed in the two age groups (21-30 and 31-40 years). CONCLUSION: Within the limitations of this study, it can be concluded that there are differences in the number and configuration of roots and root canals between maxillary first and second molars in the studied patients of a Polish population.

Evaluation of the Sealing Ability of Three Obturation Techniques Using a Glucose Leakage Test.

The aim of this study was to evaluate the sealing ability of three different canal filling techniques. Sixty-four roots of extracted human maxillary anterior teeth were prepared using ProTaper® rotary instruments. The specimens were then randomly divided into 3 experimental groups (n = 16) and 2 control groups (n = 8). The root canals were filled using cold lateral compaction (CLC group), continuous wave condensation technique using the Elements Obturation Unit® (EOU group), and ProTaper obturators (PT group). For the negative control group, 8 roots were filled using lateral compaction as in the CLC group, and the teeth were covered twice with a layer of nail varnish (NCG group). Another 8 roots were filled using lateral compaction, but without sealer, and these were used as the positive control (PCG group). A glucose leakage model was used for quantitative evaluation of microleakage for 24 hours and 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, and 12 weeks. No significant difference in the cumulative amount of leakage was found between the three experimental groups at all observation times. The lateral condensation of cold gutta-percha can guarantee a similar seal of canal fillings as can be achieved by using thermal methods, in the round canals.