Efeito de diferentes sistemas de obturação na resistência à fratura de raízes tratadas endodonticamente / The Influence of different obturation systems on the fracture resistance of endodontically treated roots

Objective: This study aimed to compare the fracture resistance of endodontically treated roots filled by different obturation systems. Material and methods: Ninety-six maxillary central incisors were used and decoronated, retaining 12 mm of the roots. On the basis of obturation systems, the roots were randomly divided into 4 groups (n=24): Group1 (COGR): control group (unprepared, unfilled), Group 2 (AVGR): ActiV GP points/ActiV GP sealer, Group 3 (GPGR): Gutta percha points / AH plus sealer, and Group4 (GAGR): Gutta percha points/ActiV GP sealer. The last three groups were obturated with the single cone technique. The roots were then stored in 100% relative humidity at 37 °C for 2 weeks. A vertical compressive force was exerted in a universal testing machine until fracture occurred. Data were statistically analyzed using one-way ANOVA. Results: Mean (SD) failure loads for groups ranged from 920.51 ± 210.37 to 1113.44 ± 489.42 N. The fracture resistance between the different study groups indicated no statistical difference (p>0.05). Conclusions: ActiV GP system did not exert a significant effect on the fracture resistance of endodontically treated teeth.(AU)

Objective: Comparar a resistência à fratura de raízes tratadas endodonticamente obturadas através de diferentes sistemas. Materiais e Métodos: Noventa e seis incisivos centrais superiores foram utilizados, tiveram as coroas removidas, restando 12 mm de raíz. De acordo com o sistema de obturação, as raízes foram divididas em 4 grupos (n=24): Grupo1 (COGR): grupo controle (sem preparo, sem preenchimento), Grupo2 (AVGR): cones ActiV GP / cimento ActiV GP, Grupo3 (GPGR): cones de guta percha / cimento AH plus, e Grupo4 (GAGR): cones de guta percha / cimento ActiV GP. Os últimos três grupos foram obturados através da técnica de cone único. As raízes foram armazenadas em 100% de umidade relativa a 37 °C durante 2 semanas. Uma força compressiva vertical foi aplicada através de uma máquina de ensaio universal até ocorrer fratura. Os dados foram analisados estatisticamente através de ANOVA ­ 1 fator. Resultados: A carga média (SD) obtida no momento da falha variou entre 920.51 ± 210.37 até 1113.44 ± 489.42 N. A resistência à fratura entre os diferentes grupos estudados não indicaram diferença estatística. Conclusão: O sistema ActiV GP não exerceu um efeito significante na resistência à fratura em dentes tratados endodonticamente.(AU)

Healing of Horizontal Intra-alveolar Root Fractures after Endodontic Treatment with Mineral Trioxide Aggregate.

INTRODUCTION: The purpose of this retrospective study was to evaluate the healing type and assess the outcome of horizontal intra-alveolar root fractures after endodontic treatment with mineral trioxide aggregate (MTA) as filling material. METHODS: The clinical database of the Department of Conservative Dentistry at Yonsei University Dental Hospital, Seoul, Korea, was searched for patients with histories of intra-alveolar root fractures and endodontic treatments with MTA between October 2005 and September 2014. Radiographic healing at the fracture line was evaluated independently by 2 examiners and was classified into 4 types according to Andreasen and Hjørting-Hansen. RESULTS: Of the 22 root-fractured teeth that received endodontic treatment with MTA, 19 cases participated in the follow-up after a period of at least 3 months. Seventeen of the 19 teeth (89.5%) exhibited healing of the root fractures. For each healing type, 7 teeth (36.8%) showed healing with calcified tissue, 8 teeth (42.1%) showed interposition of connective tissue, 2 teeth (10.5%) showed interposition of connective tissue and bone, and 2 teeth (10.5%) showed interposition of granulation tissue without healing. CONCLUSIONS: Within the limitations of this study, intra-alveolar root fractures showed satisfactory healing outcomes after endodontic treatment with MTA. MTA could be considered to be suitable filling material for the endodontic treatment of horizontal intra-alveolar root fractures.

Final Irrigation Regimens Affect Fracture Resistance Values of Root-filled Teeth.

INTRODUCTION: The purpose of this study was to compare the effect of different final irrigation solutions on fracture resistance values (FRVs) of endodontically treated teeth. METHODS: Eighty extracted decoronated human incisors were used. Ten randomly selected roots were used as the negative control group. The remaining roots were prepared by the ProTaper system (Dentsply Maillefer, Ballaigues, Switzerland) up to F2. Ten prepared roots were selected as the positive control. The other prepared roots were divided into 6 (n = 10) groups according to the final irrigation solution used: 5 mL saline, 17% EDTA, EDTA with a surfactant (REDTA), chlorhexidine, QMix (Dentsply Tulsa Dental Specialties, Tulsa, OK), and BioPure MTAD (Dentsply Tulsa Dental Specialties). In all groups, the final irrigation was performed for 1 minute except for the BioPure MTAD group; in this group, it was applied for 5 minutes according to the manufacturer's instructions. The specimens were filled with a single gutta-percha cone and AH 26 sealer (Dentsply, De Trey, Konstanz, Germany). After being stored under 37 °C and 100% humidity for a week, the specimens were loaded in a vertical direction at 1 mm/min speed until they were vertically fractured. The results were analyzed by the Kruskal-Wallis and Siegel Castellan tests. RESULTS: The negative control group showed the highest FRV. There were statistically significant differences between the negative and positive control groups (P < .05). Specimens irrigated with REDTA and QMix showed a higher FRV compared with the positive control group (P < .05). Specimens exposed to chlorhexidine and BioPure MTAD showed a lower FRV compared with the negative control group (P < .05). CONCLUSIONS: Root canal preparation weakens the tooth. The final irrigation regimen has an impact on the FRV. A short time exposure to irrigation solutions (REDTA and QMix) that include surfactants probably contributed to the higher FRV, instead of a long time exposure as done with BioPure MTAD.

Cyclic fatigue testing of denture teeth for bulk fracture.

OBJECTIVES: Clinical experience with implant-supported dentures indicates that fracture and chipping of teeth are becoming an issue. Tooth fracture and chipping rates of approximately 2.5% per year are being experienced at one university. There has been no standardized test developed for bulk fracture or chipping of denture teeth. Such a test would aid in the development of improved teeth and in their evaluation. METHODS: Central incisor teeth were embedded in acrylic and loaded on incisal edges at 90° to their long axes. Teeth tested included ones commercially available and two sets made from improved materials designed to increase toughness. Cyclic loading was done at 5Hz from 20N to 135N, 150N, 175N and 200N. Data was analyzed using lifetime analysis software fit at each of the accelerated loads and then extrapolated to clinical use loads (Alta 7, Reliasoft Corp.) Clinical use loads were derived from extrapolation of probability of failure (Pf) data to 2.5% Pf. RESULTS: When carefully embedded, teeth could be reproducibly loaded to failure by bulk fracture involving a failure mode similar to that seen clinically. Clinical use loads were calculated to be in the range of 70N. Results from accelerated loading could be fit to similar probability of failure distributions allowing extrapolation to clinical use loads. SIGNIFICANCE: This work was able to develop a clinically valid bulk fracture test for the fatigue failure of incisor denture teeth. It appears that teeth fabricated with improved materials will be expected to perform better clinically. Thus both the null hypotheses were rejected.

Mineral trioxide aggregate in the treatment of external invasive resorption: a case report.

AIM: To describe the management of external invasive resorption using mineral trioxide aggregate (MTA). SUMMARY: External invasive root resorption may occur as a consequence of trauma, orthodontic treatment, intracoronal bleaching and surgical procedures, and may lead to the progressive and destructive loss of tooth structure. Depending on the extent of the resorptive process, different treatment regimens have been proposed. A 19-year-old male patient presented with tooth 11 (FDI) showing signs and symptoms of irreversible pulpitis, external invasive resorption and periodontal pocket on the disto-palatal. After root canal treatment, the defect was accessed coronally. The resorption area was chemo-mechanically debrided using ultrasonic tips and irrigant solution. MTA was used to fill the resorptive defect, and the coronal access was temporarily sealed. The definitive coronal restoration was performed after 3 days. Radiographs at 1, 2 and 4 years showed adequate repair of the resorption and endodontic success. Clinically, the tooth was asymptomatic, and no periodontal pocket was found. KEY LEARNING POINTS: *Mineral trioxide aggregate was successfully used to restore a small area of external invasive resorption. *A coronal approach can sometimes be successfully used in order to avoid surgery and periodontal complications.

Equine idiopathic cheek teeth fractures: part 3: a hospital-based survey of 68 referred horses (1999-2005).

REASONS FOR PERFORMING STUDY: There is limited information available on the more serious sequellae of idiopathic cheek teeth (CT) fractures. OBJECTIVES: To obtain information on clinical and ancillary diagnostic findings in referred horses with idiopathic CT fractures. METHODS: Details of all horses suffering from idiopathic CT fractures referred to the Equine Hospital at the University of Edinburgh 1999-2005 were examined, and information concerning fracture patterns, clinical and ancillary diagnostic findings, treatments and long-term response to treatments were obtained and analysed. RESULTS: A total of 60 maxillary and 17 mandibular idiopathic CT fractures were diagnosed in 68 horses. Fracture patterns included maxillary CT lateral slab fractures (45%), maxillary CT midline sagittal fractures (16%) and various other patterns of maxillary CT fractures (17%). In the mandibular CT, lateral slab fractures were found (12%) and various other CT fracture patterns were present in 10%. The more centrally positioned CT (maxillary and mandibular Triadan 08s and 09) were preferentially fractured. Clinical signs included quidding in 47% of cases; bitting and behavioural problems (28%); signs of apical infection, including bony swellings and nasal discharge (21%); anorexia/weight loss (15%); halitosis (13%); and buccal food impaction (12%). The treatment of all cases was conservative whenever possible and included corrective rasping of the remaining tooth (46% of cases); oral extraction of the smaller and loose dental fragment (32%) and extraction of the entire fractured tooth by oral extraction (28%) or by repulsion (13%). Prophylactic treatment of adjacent, nonfractured CT with carious infundibula was possibly of value in preventing further midline sagittal maxillary CT fractures. CONCLUSIONS: Horses referred with idiopathic CT fractures frequently have clinical signs of apical infection of the fractured CT and these teeth require extraction, orally if possible. More conservative treatment of idiopathic CT fractures without signs of gross apical infection can resolve clinical signs in most cases. POTENTIAL RELEVANCE: In the absence of apical infection, extraction of only the loose dental fragments of CT with idiopathic fractures is usually successful.

Nonsurgical treatment of periapical lesions using intracanal calcium hydroxide medicament--a report of 2 cases.

Periapical pathology is the most common sequelae of pulpal necrosis due to traumatic injury. For the success of endodontic treatment, healing of periapical pathology is necessary and can be achieved by maintaining a sterile root canal system. Calcium hydroxide has the potential to maintain a sterile root canal by its antibacterial and tissue-dissolving property. Two case reports of periapical pathology that healed within a period of 3 to 6 months after intracanal calcium hydroxide dressing are presented.

Use of 2-octyl cyanoacrylate for the repair of a fractured molar tooth.

Odontalgia in association with an acutely fractured tooth is a frequent reason for emergency department presentation. We describe the case of a patient who presented with a painful fractured molar tooth and was treated with topical application of 2-octyl cyanoacrylate tissue adhesive, resulting in prompt relief of her discomfort and a good temporary functional and cosmetic outcome. This product may prove useful in treating similar dental emergencies when access to emergency dental care is unavailable.

Utilización del compuesto trióxido mineral MTA en casos de apexificación / The uses of mineral trioxide agregate MTA in apexification cases

Este estudio corresponde a una serie de 20 casos donde se utilizó el compuesto trióxido mineral MTA para tratar distintos casos de apexificación. Se seleccionaron pacientes que presentaban piezas permanentes superiores, no vitales, con antecedentes de traumatismo, e interrupción del desarrollo radicular, cuyas edades fluctuaban entre los diez y catorce años. El propósito de este estudio fue conocer las propiedades, ventajas e indicaciones del MTA y la viabilidad del protocolo utilizado en estos tratamientos. De acuerdo al protocolo del tratamiento, los conductos radiculares fueron irrigados con hipoclorito de sodio al 2.5 por ciento y medicados con una pasta de hidroxido de calcio por 15 días. Seguidamente, la porción apical fue sellada con MTA (3mm) y la porción remanente con gutapercha y cemento Grossman. Estos casos, que tradicionalmente fueron tratados con hidróxido de calcio por extensos períodos de tiempo, al ser sellados con MTA, fueron dados de alta en una sola sesión, y completaron el cierre radicular en un plazo de 6 a 8 meses. Sin embargo, son necesarios nuevos ensayos clínicos que prueben la efectividad de este material.

[Fractures of the canines require attention]. / Een hoektandfractuur verdient de juiste aandacht.

Hardly any attention was paid to a barely visible fracture of a canine tooth (104) in an 18-month-old dog. When the dog was 6-years old, a fistulous opening was seen on the bridge of the nose. A year later, radiography revealed a periapical process. The investigations performed and treatment given are described, as is the correct way to handle fractures of the canines.

Reubicación quirúrgica de incisivos con fracturas corono-radiculares por medio de rotaciones intraalveolares / Surgical reimplantation of incisors with crown-root fractures through intralveolar movements

En este artículo se presentan los resultados obtenidos al tratar un niño que presentaba una fractura corono-radicular, mediante la utilización de un tratamiento alternativo, que logra a través de pequeños movimientos intraalveolares la reubicación quirúrgica de estas piezas dentarias, muchas veces destinadas a perderse