ENDO, 01/2011

The technical management of roots with S-shaped root canals to achieve both proper shaping and thorough cleaning is difficult and demanding. Little has been written that specifically addresses the clinical challenges encountered in these anatomically irregular roots. The purpose of this article is to detail techniques that can be used to efficiently and safely complete the entire root canal procedure on teeth with S-shaped roots and to amplify this accomplishment using a case report and treatment outcome. Keywords: anatomical irregularities, debridement, shaping, S-shaped canals

Aim: To compare in vivo the accuracy of five electronic apex locators (EALs) in determining the working length, set at a target reference length of 1.0 mm short of the radiographic apex. Methodology: Clinically healthy adult patients with a total of 100 teeth (232 canals) participated in this investigation. Informed written consent was obtained from each patient under a study protocol approved by an ethical committee from the Ministry of Health. Electronic working length (EWL) was determined by the apex locators, which were divided, for simplicity, into two groups with an equal number of canals (116 canals for each group). Group 1 consisted of the Root ZX II, the Apex D.S.P., and the Elements Diagnostic Unit and Apex Locator; group 2 consisted of the NaviRoot and the SiroEndo Pocket. All tested EALs were used according to their manufacturer's instructions. Radiographic working length (RWL) was determined by the operator prior to the EWL and was set at the general and universal agreement of 1.0 mm short of the radiographic apex. Verifications of the RWL measurements were blindly and randomly analysed by two independent evaluators (endodontists): IE1 and IE2. Finally, the results of the two groups were compared (intra-group comparison) using a paired sample t test. The level of significance was set at P < 0.05. Results: Matching measurements between the apex locators and RWL, IE1 and IE2 were as follows: for Root ZX II, 104 canals (89.66%), 97 (83.62%) and 92 (79.31%), respectively; for Apex D.S.P., 80 canals (68.97%), 79 (68.10%) and 80 (68.97%), respectively; for Elements Apex Locator, 88 (75.86%), 87 (75%) and 85 (73.28%), respectively; for NaviRoot, 85 (73.28%), 84 (72.41%) and 84 (72.41%), respectively; and for SiroEndo Pocket, 81 (69.83%), 81 (69.83%) and 79 (68.10%), respectively. There were no statistically significant differences between IE1 and IE2, IE1 and RWL, and IE2 and RWL in both groups (P > 0.05). No statistically significant differences were found between the following variables: Root ZX II and RWL; IE1 and IE2; Apex D.S.P. and IE2; Elements Apex Locator and RWL, IE1 and IE2; and NaviRoot and RWL, IE1 and IE2 (P > 0.05). There was a statistically significant difference between the following variables: Apex D.S.P. and RWL and IE1; and SiroEndo Pocket and RWL, IE1 and IE2 (P < 0.05). Conclusion: Within the limitations of this study, the results showed that all tested EALs achieved an acceptable determination of the root canal working length within ± 0.5 mm from the target reference point in a range of 75% to 95% of cases. Keywords: electronic apex locators, electronic working length, endodontics, radiographic working length

This report describes the management of persistent apical periodontitis by combined non-surgical and surgical retreatments. The patient had a history of trauma to his four mandibular incisor teeth and presented pain, intermittent swelling and a draining sinus tract of 9 years duration. All of the teeth had previously been root-canal treated and undergone two surgical retreatment procedures. Non-surgical retreatment was performed and untreated lingual canals were found in three teeth. This was followed by surgery to correct deficiencies in the root-end fillings and to biopsy the lesions. New post-retained crowns were provided, and nine years later there is evidence of continued healing. Keywords: endodontic retreatment, periapical granuloma, periapical surgery, radicular cyst, treatment outcome

Tooth resorption is a physiologic or pathologic interactive process, involving inflammatory cells, resorbing cells and hard tissue structures, which is similar to bone resorption. This is a case report detailing the complete root resorption of a maxillary right permanent central incisor following root canal treatment. Persisting infection and inflammation had led to continual root resorption, to the extent that there was a complete loss of the root structure and replacement by osseous tissue. Keywords: infection, inflammation, resorptive cells, root resorption

The complexity of the root canal system of maxillary molars presents a constant challenge, as the dentist must have a thorough knowledge of the root canal morphology to provide successful endodontic treatment. This report presents the endodontic management of three cases of maxillary second molars with two separate palatal roots. Keywords: canal complexity, maxillary second molars, two palatal roots

A 15-year-old female presented for root canal treatment of a symptomatic left maxillary central incisor. Although the internal anatomy of the maxillary central incisor is well known and usually presents with one root and a relatively simple root canal system, a second root with a separate root canal was located, treated and the patient's symptoms were eliminated. The purpose of this case report is to describe the diagnosis and root canal treatment of a maxillary central incisor with two roots and two canals. Keywords: anatomical variation, diagnosis, maxillary central incisor, multi-rooted tooth, root canal treatment

Immature teeth with open foramina present a challenge in root canal treatment. An approved method is apexification using long-term calcium hydroxide dressings, but this approach is associated with a number of clinical problems. The creation of an apical plug is an alternative treatment for teeth having open apices. Mineral trioxide aggregate (MTA) has shown potential as a root-end filling material especially in immature teeth. MTA can be considered a very effective option for apexification with the advantage of reduced treatment time, good sealing ability and high biocompatibility. Four clinical cases describing the treatment of maxillary incisors with necrotic pulp, open apices and apical periodontitis (using the apical plug procedure with MTA) are presented. All cases showed clinical and radiographic signs of healing after apical plugging with MTA. Keywords: apexification, MTA

Aim: To report the root canal treatment performed on a three-rooted maxillary first premolar. Summary: Many of the difficulties found in endodontic therapy are caused by variations in root canal anatomy. Most commonly bi-rooted, the maxillary first premolar can also have three roots with three independent canals at the apex. This case report describes the root canal treatment performed on a maxillary first premolar with three independent root canals in three distinct roots. Good knowledge of the endodontic anatomy and good interpretation of the periapical radiographs are very important skills in recognising the unusual morphology of the teeth and performing a predictable endodontic treatment. Special care needs to be taken during clinical examination, refining the access cavity, locating the orifices of the root canals on the pulpal floor and cleaning, shaping and filling all identified root canals. Keywords: endodontic therapy, maxillary first premolar, root canal anatomy