ENDO, 02/2014

The outcome of root canal treatment is influenced by its quality and epidemiological studies have reported a high prevalence of persistent apical periodontitis in teeth with sub-optimal root canal fillings. One of the main causes of root canal treatment failure is the persistence of intraradicular infection in the root canal system, which may not be due to a particular microorganism, but on the capability of communities of bacteria to adapt to changes occurring in the root canal environment following root canal treatment. Intraradicular infection can persist in the complex apical root canal anatomy such as canal irregularities, deltas and isthmus areas, and accessory canals. Bacteria in these untouched locations are primarily organised as biofilms - protected adhesive structures composed of microorganisms embedded in a hydrated polymeric complex. Numerous studies have demonstrated the presence of biofilms in root canal-treated teeth with persistent apical periodontitis. Microorganisms display an increased tolerance to antimicrobial agents and an enhanced pathogenic potential when growing as a biofilm. The biofilm mode of growth may constitute an important mechanism for the persistence of bacteria in the harsh environment of root canal-filled teeth. This review supports the argument for the inclusion of the biofilm concept in the aetiology of root canal treatment failure. Endodontic treatment should be provided to the highest standard if it is to tackle the intraradicular biofilm and reduce the risk of treatment failure. Keywords: biofilm, endodontic treatment failure, intraradicular infection, persistent apical periodontitis

Presence of a tooth with simultaneous lesions of endodontic and periodontal origin is a challenge to the clinician as far as diagnosis, prognosis and decision-making are concerned. Such infections are typically polimicrobial, and therefore interactions, both antagonistic and synergistic, between different strains and species would be expected. Treatment and prognosis of endodontic-periodontal lesion depend on the cause and the correct diagnosis of each specifying condition. In particular it is critically important to determine whether the lesion is primarily periodontal or primarily endodontic in origin, because the accuracy of diagnosis will determine whether or not the appropriate treatment plan is instigated. Keywords: bacteria, endo-perio lesions, root canal therapy

While non-surgical endodontics is the mainstay of the endodontic specialist, surgical procedures are often necessary to save teeth. Most patients are aware of their aesthetic smile and are not willing to compromise their appearance to save a tooth. Predictable aesthetic results may be achieved by a skilled hand and thorough knowledge of surgical flap design and maintenance. The purpose of this review is to present a thorough appraisal of the accepted and predictable flap designs as well as review guidelines for tissue handling and closure. It may be concluded that endodontic surgery offers a significant contribution to endodontic practice; that treatment is performed using sound surgical principles with appropriate case selection; and that flap design can offer successful outcomes without compromising aesthetics. Keywords: endodontics, flap, management, microsurgery, surgery

Minimum intervention and retention of every part of the tooth structure is an imperative objective in contemporary endodontic practice. Nevertheless, elective (intentional) root canal treatment (RCT) of sound teeth with normal pulps may be necessary. This article aims to define the criteria for considering RCT as an elective treatment, to discuss the indications of this approach and the prevalence among different countries, and to outline special precautions that should be considered when commencing elective RCT. In addition, other elective pulp treatment procedures are highlighted. Keywords: elective, intentional, prevalence, root canal treatment

Aim: The aim of the present study was to evaluate the correlation between estimated endodontic treatment need and perceived endodontic treatment after 1 year. Methodology: Panoramic radiographs and sensibility testing were taken from 536 patients at their first visit at all of 9 selected dental offices. The results were evaluated by two investigators and endodontic treatment need was calculated. After a period of at least 1 year, the charts of these patients were checked for any endodontic, surgical or restorative treatment on teeth with an estimated endodontic treatment need. Results: On the first visit, 4.2% of the teeth already showed a root canal filling. Minimum and maximum treatment need was calculated to be 2.9% and 9.4% of the teeth, respectively. Only 27% of teeth requiring primary endodontic treatment and 10% of teeth requiring retreatment had received an endodontic therapy 1 year later. Additionally, 30 teeth without an expected treatment need received primary endodontic treatment and 7 teeth without need for retreatment received endodontic therapy. Conclusion: The endodontic treatment need and actually performed endodontic treatment did not conform. Less than half of the teeth with endodontic treatment need had received endodontic treatment within 1 year. Keywords: decision making, endodontic treatment need, perceived treatment, retreatment need

Introduction: This study evaluated the cross section, resistance to bending and buckling of Reciproc and WaveOne instruments. Methods: Reciproc R25 (VDW, Munich, Germany) and WaveOne Primary (Dentsply Maillefer, Ballaigues, Switzerland) instruments, all of them 25-mm long, with D0 diameter of 0.25 mm and taper of 0.08 mm/mm along the first 3 mm from the tip, had their cross section analysed and were subjected to bending and buckling resistance tests. The data from both tests were analysed using the Student t test. Results: A statistically significant difference was observed between the maximum load to bend Reciproc 25 and WaveOne Primary instruments (P 0.05). Higher values were necessary to bend WaveOne Primary instruments when compared with Reciproc R25. In contrast, there was no statistically significant difference between the maximum load to buckle Reciproc 25 and WaveOne Primary instruments (P > 0.05). Conclusions: Both instruments exhibited similar behaviour in terms of buckling resistance. However, Reciproc R25 was more flexible, which is an important instrument property for the shaping of narrow and curved root canals. Keywords: bending resistance, buckling, M-Wire, nickel-titanium, reciprocating technique

Introduction: Dens invaginatus is a malformation of the tooth during embryonic development that presents in several morphological types. This article reports a case of a type II dens invaginatus with an extensive periradicular lesion that was treated successfully. Methods: Three-dimensional imaging, cone beam computed tomography (CBCT) was used to identify the morphology of dens invaginatus and to help devise a treatment plan. Nonsurgical and surgical endodontic treatments were performed to achieve a favourable outcome. Conclusions: Understanding both the configuration of the internal root canal and irregularities of the external root using CBCT can ensure predictable and successful results, as in this case. The 2-year follow-up showed complete healing of the periapical pathosis. Keywords: cone beam computed tomography (CBCT), dens in dente, dens invaginatus, endodontic surgery, endodontic treatment