[Success of pulpotomy with MTA in permanent human molar teeth]

Statement of Problem: Preservation and maintenance of pulpal vitality is the main objective in endodontics. A recently developed material, mineral trioxide aggregate [MTA], is recommended for vital pulp therapy because of its physical characteristics and bioactive properties. Although the majority of these studies have been performed on the teeth with open apices, further evaluation of the teeth with closed apices seems to be necessary

Purpose: The purpose of this study was to evaluate the pulpal reaction to MTA after pulpotomy in permanent molar teeth with caries

Methods and Material: In this clinical case series study, 17 permanent molar teeth of 16 patients with a carious exposure were treated, using a partial pulpotomy technique. The age of the patients ranged from 20 to 30 years with an average of 25.2 years. Clinical and radiographic examination revealed a pulpal response within normal limits and normal appearance of the periradicular area respectively. After isolation, caries removal and pulpal exposure, access cavity was prepared using a sterile diamond bur with cooling system. After hemostasis, 2 to 4 mm of MTA [Angelus] paste was placed on the fresh wound. The teeth were restored 5-7 days later with amalgam or composite. The patients were scheduled for follow-up at an interval of 2, 6 and 12 months, and clinical and radiographic findings were established

Result: An overview of the data with respect to the clinical and radiographic findings at 2, 6 and 12 months of follow-up showed 100% success rate

Conclusion: Pulpotomy therapy, if the teeth are appropriately selected and MTA is used in suitable conditions especially when conventional treatment is not possible, gives a chance to the pulp to recover and could be the treatment of choice. In case the treatment fails, retreatment thereafter is possible. Nevertheless, further investigations with more samples are recommended for final judgment

[ in vitro evaluation of root anatomy, detection of apical foramen and apical constriction in human mandibular premolar teeth]

Complete knowledge of the morphologic and microscopic anatomy of the dental root apex has been recognized. Internal root canal anatomy especially root apex is variable in human teeth for example lateral canal and ramification may exist. The objective of this study was to determine the internal anatomy of root apex. For this investigation, 50 mandibular first premolar and 50 mandibular second premolar were obtained. The age and sex of the patients and reasons for extraction were not recorded. For better recognition of apical foramen and lateral foramen of the teeth, they were placed in methylen blue for 2 hours and then teeth were studied under the stereomicroscope with x25 magnification lens [the calibration of lens was 0.1mm] and percentage of lateral canal, root deviator and apical foramen exit were detected. Then, to study the internal anatomy, the teeth were grinded and stained with hematoxylin. The mean, standard deviation and standard error for the diameter of constriction and distance from apical foramen were measured. Also, the internal anatomy of the root canal was studied by two observers. The results showed that apical constrictions were always smaller than apical foramen and a distance existed between apical constrictions, apical foramen and vertex. Apical foramen did not exist in center in 80 to 90% of cases. Lateral canals were observed in 28% of mandibular first premolar and in 34% of mandibular second premolar. Also, 90% of first premolar teeth and 88% of second premolar teeth had one canal and 10% of first premolar and 12% of second premolar had two canals. As the mean distance between apical constriction and apical vertex in mandibular first premolars was 0.65mm and in mandibular second premolars was 0.68mm, therefore during root canal treatment and working length determination, this distances should be decreased from tooth length

in vitro evaluation of coltozole, amalgam, glassionomer and MTA [mineral trioxide aggregate] as barriers to coronal microleakage in endodontically treated teeth

Because commonly used obturating materials can not provide hermetic seal against saliva and microorganisms in the root canal system, thus it has been suggested that the use of intraorifice sealing of Gutta percha obturated root canals to prevent coronal micorleakage. The purpose of this study was to evaluate coronal micorleakage of four materials used as an intraorifice plug. After cleaning, shaping and conventional obturation of 86 extracted human single root canal and, a 3 millimeters of the gutta percha was removed from the coronal aspect of the root canal and replaced with one of the four filling materials: MTA, Glass lonomer [GI], Coltozole and Amalgam. Microleakage was evaluated by using of staining penetration methods with Indian ink and after clearing of the specimens, the linear dye penetration was measured. The mean of linear dye penetration for each group was compared by the ANOVA and Post Hoc test. The results showed that GI group had significantly the most leakage and the other experimental groups of Amalgam and Coltozole significantly sealed better. On the other hand, the MTA group had significantly the least leakage. The result of this study showed that although the three experimental materials [Amalgam, Coltozol and MTA] except GI were able to decrease the coronal microleakage, but none of them were able to prevent microlaeakge completely. So, use of orifice plug to reduce coronal microlaekage which is one of the important causes of failure in endodontic, seems to be useful

[ radiographic evaluation of degree of root curvature in treated permanent teeth in endodontics department in Shiraz dental school [2001-2002]]

Statement of Problem: The major objectives of root canal treatment are removal of all irritant from the root canal space and accomplish a proper shaping of the space and total obturaion of this space. So, diagnosis of root curvature is critical and can affect on proper preparation and prevention of procedural accidents

Purpose: The aim of this study was to measure and evaluate the root curvature of permanent teeth that were treated at Endodontic Department of Shiraz Dental School [2001- 2002]

Materials and Methods: In this case control study, all endodontic treated patients with standardized radiographic films to determine the working length were analyzed and the angel of root curvature, were evaluated by Schneider method. After image projection and drawing of two lines, one on long axis of the canal and the other from apical foramen to the first line, the constructed angel was measured

Results: From 398 evaluated films, the root curvatures in posterior teeth were more than that in anterior teeth. Most of the roots [80%] had root curvatures directed to the mesial or distal plane although root curvatures to distal plane were more common. All of the roots had mild to moderate curvatures [0-25 degrees] except the mesial root of the first mandibular molar that had severe root curvature [more than 25 degrees]. The mean of root curvature of permanent teeth were between 2.76 to 28.28 degrees

Conclusion: The results indicated that root curvatures in teeth were common and practitioners should be aware in the case of any difficulty, and refer the case to a specialist