ENDO, 02/2015

The aim of this clinical case report is to discuss the efficacy of cone beam computer tomography (CBCT) in the diagnosis, treatment planning and follow-up of traumatised teeth. Ten clinical cases involved in dental trauma such as crown fracture, crown-root fracture, root fracture, subluxation, intrusion and avulsion were discussed. CBCT could reveal even slight changes of periodontal tissues, teeth structures and pulp tissues; and their involvement in dental trauma. In conclusion, CBCT could provide more precise images not only for diagnoses but also for the healing process after treatment, rather than when using periapical radiation alone. Keywords: cone beam computer tomography, transient apical breakdown, traumatology

In young patients autologous tooth transplantations offer a good treatment option in cases of missing teeth or in cases of tooth loss as a sequela of dental trauma. Teeth suited for transplantation are; premolars, which can be transplanted into the anterior or premolar region; or wisdom teeth to replace lost molars. In immature teeth the diameter of the apical foramen must be at least 2 mm wide to pursue revascularisation of the pulp tissue. When a mature tooth is transplanted, root canal treatment will be necessary. On the basis of three case reports, the necessity of interdisciplinary treatment, which includes oral surgeons, endodontists, restorative dentists and orthodontists, has been demonstrated. Inaccurate treatment planning and problems during surgery will significantly reduce the prognosis of the transplanted tooth. Ankylosis, resorption, pulp necrosis or the loss of the transplanted teeth are some of the major complications after transplantation. Thorough treatment planning, gentle surgical technique and a regular checkup are major prerequisites for a good prognosis of tooth transplantation. Keywords: interdisciplinary treatment, root canal treatment, tooth transplantation

The availability of hig h level micro-computed tomography (micro-CT) or X-ray computed tomography (X-ray CT) equipment has enhanced the evaluation of both tooth anatomy and the application of new technology that is being developed for root canal procedures. Keywords: anatomy, endodontics, micro-CT, radiographs, root canal procedures

Introduction: Bioceramic materials are currently available in three forms: sealer, paste and putty, and consists of a variety of clinical applications. Some are premixed and some require manual mixing. They are fairly new to endodontics and not understood properly by most clinicians. The purpose of this article is to discuss the current premixed bioceramic materials, give an overview of the literature, and present five clinical cases in which they were used successfully. Methods: Five cases were selected in which bioceramic materials were used for retreatment, perforation repair and periapical surgery. Recalls up to 2 years are presented. Conclusions: This case series shows that bioceramic materials can be used successfully to manage a variety of clinical scenarios and offers some potential advantages over other materials. In each case, treatment resulted in the elimination of clinical symptoms and bone healing. Keywords: bioceramic materials, case report, perforation repair, retreatment, surgery

Aim: This study compared the incidence of deviation along curved canals after preparation with three nickel-titanium (NiTi) rotary systems (K3XF, Mtwo and BioRaCe). Materials and methods: Curved canals from 60 resin training blocks were filled with ink and divided into three groups according to the instrumentation system. Pre-instrumentation images were acquired by using a stereomicroscope. All canals were prepared up to an instrument size 35/0.04 at the terminus of the canal. Post-instrumentation images were taken using the same conditions and pictures were superimposed. The amount of resin removed was measured at eight different points, beginning at the apical terminus of the canal. Differences in the mesial and distal aspects were measured to evaluate the occurrence of deviation. Results: Intragroup analysis showed that all instruments promoted some deviation at all levels. There was a significant difference at most of the levels for all groups (P < 0.05), except for the 1-mm level of the K3XF (P = 0.099) and Mtwo (P = 0.196) groups, the 3-mm level of BioRaCe group (P = 0.071) and the 7-mm level of the Mtwo (P = 0.051) and BioRaCe (P = 0.257) groups. Deviation was observed at the distal canal wall at levels 3, 4, 5 and 6 from all groups, at level 2 from both K3XF and Mtwo groups, at level 1 from the K3XF group and at level 7 from the Mtwo group. At the mesial wall, deviation was observed at level 0 from all groups, at level 1 for both Mtwo and BioRaCe groups and at level 7 for both K3XF and BioRaCe groups. Mtwo showed significantly lower deviation at level 1 than K3XF and BioRaCe. At level 2, BioRaCe was significantly better than Mtwo and K3XF and Mtwo performed better than K3XF. No significant differences were observed for the other levels. Conclusions: All the rotary NiTi systems showed some deviation during the preparation of curved canals. Mtwo showed a significantly better performance at level 1 and BioRaCe at level 2. Keywords: curved root canals, root canal deviation, root canal preparation, rotary nickel-titanium instruments

Aim: This study compared the mechanical properties of ProTaper Next, ProFile Vortex and OneShape instruments. Materials and methods: The instruments were subjected to mechanical tests to evaluate microhardness, cyclic fatigue, resistance to bending and torsional load in a clockwise rotation. Analysis of variance (ANOVA) and the Student-Newman-Keuls test for multiple comparisons were employed to evaluate the data. Results: In the bending resistance test, significant differences were observed when comparing both ProTaper Next and ProFile Vortex to OneShape (P < 0.05), however there was no significant difference between ProTaper Next and ProFile Vortex (P > 0.05). OneShape's bending resistance was found to be significantly higher. In the fatigue resistance test, ProTaper Next was found to be most resistant, followed by OneShape then ProFile Vortex. Statistical analysis suggests a significant difference in angular deflection at failure between all instruments tested (P < 0.05). Considering maximum torque, significant differences were found between ProFile Vortex and OneShape, and between Pro- Taper Next and OneShape (P < 0.05), however there was no significant difference between ProFile Vortex and ProTaper Next instruments (P > 0.05). Maximum torque was significantly higher for One- Shape. Vickers microhardness did not differ significantly amongst all instruments tested (P > 0.05). Conclusion: The ProTaper Next instruments were found to be the most flexible and most resistant to cyclic fatigue while the OneShape instruments outperformed the others when evaluating deflection at failure and maximum torque. Keywords: bending resistance, cyclic fatigue, flexibility, M-Wire, nickel-titanium alloy, torsional resistance