Negotiating and Treating Lateral Canals: Report of 7 Cases.

This is a series of 7 cases in which the operator penetrated lateral canals with instruments. Two teeth presented with irreversible pulpitis, 4 with necrotic pulps, and 1 with previous treatment. Except for the teeth with pulpitis, all the others were associated with apical periodontitis. The main root canal was always relatively straight, with the lateral canals at the middle third of the root. Suggestive images of lateral canal presence were seen on periapical radiographs in five cases. The clinician introduced intentionally small hand instruments in the lateral canal in 5 cases, while the penetration was fortuitous in the others. The lateral canals were obturated in all cases. Follow-up examination was possible in five cases, all of them showed evidence of successful clinical and radiographic outcomes. Introducing files into lateral canals may permit some preparation and penetration of irrigant solution, favoring disinfection and, consequently, enhancing the treatment outcome. (EEJ-2023-05-063).

Effectiveness of supplementary antimicrobial procedures in disinfecting lateral canals as evaluated by a novel ex vivo analytical approach.

This ex vivo study devised an analytical ex vivo method for infection/disinfection of simulated lateral canals located in the middle and apical segments of the root. The antibacterial effects of supplementary approaches were tested in this model. Extracted mandibular premolars had their main root canals enlarged and then two lateral canals (100 µm in diameter) were created in the root, one in the apical and the other in the middle portion. Micro-computed tomography was used for specimen selection and to confirm the quality of the simulated ramifications. The specimens were contaminated with a mixed bacterial culture from subgingival bacterial biofilm added to pure Enterococcus faecalis strain ATCC 29212 grown overnight, using special strategies to facilitate culture medium penetration within the lateral canals. The following procedures were tested for disinfection: NaOCl/passive ultrasonic irrigation (PUI), NaOCl/XP-endo Finisher, ozonated water/continuous ultrasonic irrigation (CUI), and NaOCl/conventional irrigation with 30-G needles (control). Bacteriological samples were taken from the main canal before (S1) and after (S2) each supplementary protocol, and also from each lateral canal after treatment (S3). DNA extracted from the samples was subjected to quantitative real-time polymerase chain reaction. All S1 main canal samples were positive for bacterial presence. Bacterial counts in the main root canal substantially decreased by 99.2% after PUI, 99.1% after ozone/CUI, 99% after XP-endo Finisher, and 96% in the control group (P < 0.01 for all groups). There were no significant differences between groups (P > 0.05). The same was observed when comparing the effects of the supplementary approaches in the apical and middle lateral canals (P > 0.05). Only a few lateral canals showed no detectable bacteria. The method proposed here proved effective for ex vivo infection/disinfection studies. All supplementary approaches induced a substantial bacterial reduction in the main canal, with no significant differences between them. However, in terms of lateral canal disinfection, none of the tested approaches showed significant effects when compared to the control group.

Successful regenerative endodontic treatment in a tooth with incomplete root apex and posttreatment apical periodontitis: A case report.

This case report describes the procedure and outcome of regenerative endodontic treatment (RET) in a tooth with incomplete root apex and posttreatment apical periodontitis. A 44-year-old patient was referred to the endodontist because of a periapical lesion on tooth #21 and a recent episode of acute periapical abscess. On clinical and radiographic examination, this tooth presented with tenderness to percussion and palpation, periapical radiolucent lesion, external apical resorption, and incomplete apex formation. After coronal access, the filling material was removed, and the canal was gently prepared with hand files, using 1% NaOCl as the main irrigant followed by final irrigation with 17% EDTA, activated with XP-endo Finisher (FKG Dentaire, La Chaux-de-Fonds, Switzerland). The root canal was filled with a double antibiotic paste with ciprofloxacin and metronidazole (1:1). After three weeks, RET was performed by stimulating bleeding into the canal, and when a clot was formed, a bioceramic (EndoSequence BC Sealer, Brasseler USA, Savannah, GA) plug was placed on it, followed by coronal restoration. The tooth remained asymptomatic since RET was concluded. Clinical and radiographic follow-ups showed complete repair of the apical periodontitis lesion and the absence of symptoms after eight months. This satisfactory outcome was confirmed after 34 months. Key words:Bioceramic material; ciprofloxacin; metronidazole; persistent apical periodontitis; regenerative endodontic treatment.

Dens Invaginatus: Clinical Implications and Antimicrobial Endodontic Treatment Considerations.

Dens invaginatus or dens in dente is a developmental dental anomaly resulting from an invagination of the enamel organ into the dental papilla during odontogenesis. Radiographically, it is usually seen as a radiolucent invagination surrounded by a radiopaque area (enamel) limited to the tooth crown or extending into the root. Because the invagination is opened to the oral cavity, it can retain saliva, food remnants, and bacteria. In conditions where the enamel lining of the invagination is naturally absent or lost because of caries, bacterial cells and products can diffuse from the invagination through the dentin tubules to reach the pulp and cause disease. Management of teeth with dens invaginatus includes preventive sealing or filling of the invagination, or if the pulp is affected, therapeutic options include vital pulp therapy, nonsurgical root canal treatment, apexification or regenerative endodontic procedures, periradicular surgery, intentional replantation, or extraction. It is recommended that the invagination be always approached, regardless of the type of dens invaginatus. The root canal should be treated whenever the pulp is irreversibly inflamed or necrotic. Endodontic management of teeth with dens invaginatus is often tricky because of its anatomic complexity, and special and customized strategies should be devised. This review discusses the endodontic implications of this anomaly and the current treatment recommendations based on anatomic, pathological, and technologic considerations.

Management of teeth with dens invaginatus and apical periodontitis: A case series.

BACKGROUND: Dens invaginatus is a dental anomaly that can predispose the tooth to pulp and periapical pathology. CASE DESCRIPTION: Different endodontists treated 6 maxillary incisors with dens invaginatus associated with apical periodontitis. Cone-beam computed tomography was used to help with diagnosis and treatment planning in most patients. Four patients received diagnoses of Oehlers type II dens invaginatus and the other 2 as type III. In some patients with type II, the invagination had to be perforated to permit access to the apical part of the true root canal. Both the true canal and the invagination (pseudocanal) were treated in all cases using an antimicrobial regimen based on chemomechanical preparation with sodium hypochlorite irrigation and supplementary disinfection approaches. Calcium hydroxide medication was used in all but 1 case. The root canal and invagination were often filled using thermoplasticized gutta-percha techniques, sometimes using an apical plug with a bioceramic material in teeth with large apical openings. All treated patients had favorable clinical and radiographic outcomes. PRACTICAL IMPLICATIONS: Regardless of the complex anatomic variations, common strategic therapeutic approaches were identified that might serve as recommendations for proper management of teeth with dens invaginatus and apical periodontitis. These approaches include cone-beam computed tomographic planning, aggressive disinfection using sodium hypochlorite ultrasonic or sonic activation and calcium hydroxide intracanal medication, and thermoplasticized gutta-percha obturation of both the root canal and invagination.

Influencia de los Diseños de Agujas Endodónticas en la Irrigación de Conductos Radiculares

RESUMEN: La irrigación del sistema de conductos radiculares con soluciones antibacterianas es considerada una parte esencial de la preparación químico-mecánica. Varios factores influyen en la eficacia de la irrigación del conducto radicular, incluyendo tamaño de la preparación apical y ensanchamiento, distancia de penetración de la aguja con respecto al ápice, flujo y volumen de sustancia de irrigante, dimensión de las agujas y la presencia de curvatura del conducto radicular. El tamaño de la preparación apical y la conicidad afectan el recambio del irrigante, el esfuerzo de corte en las paredes del conducto radicular y la presión en el foramen apical. La colocación de la punta de la aguja más cerca del ápice, permite un recambio de la solución más eficiente, resultando una mejor limpieza y desinfección del conducto radicular. La velocidad del irrigante, al lado de la aguja, en las paredes del conducto opuestas y frente a la salida de la aguja es dependiente del diseño de la aguja. El patrón de flujo y recambio del irrigante de las agujas con extremo abierto es diferente al de las agujas cerradas y las que logran mejor recambio de irrigante en la parte apical del conducto radicular también conducen a un aumento de la presión media en el foramen apical, lo que indica un mayor riesgo de extrusión del irrigante hacia el tejido periapical. El objetivo de esta revisión a la literatura, es evaluar los diferentes diseños de agujas y su influencia en la irrigación del sistema de conductos radiculares.

ABSTRACT: Root canal irrigation with antibacterial solutions is considered an essential part of the chemical-mechanical preparation. Several factors influence the efficacy of root canal irrigation, including apical preparation size and taper, needle penetration distance from the apex, flow and volume of irrigant substance, dimension of the needles and the presence of curvature of the root canal. The apical preparation size and the taper affect irrigant replacement, shear stress on the root canal walls, and pressure on the apical foramen. Placing the tip of the needle closer to the apex, allows more efficient solution exchange, resulting in better cleaning and disinfection of the root canal. The velocity of the irrigant, next to the needle, on the opposite canal walls and in front of the needle outlet is dependent on the design of the needle. The flow and irrigant replacement pattern of open ended needles is different from needles with closed tip. The needles that achieve better irrigant exchange in the apical part of the root canal also lead to an increase in mean pressure in the apical foramen which indicates a greater risk of extrusion of the irrigant into the periapical tissue. The objective of this literature review is to evaluate the different needle designs and their influence on the root canal system irrigation.

¿Los Quistes Periradiculares Dependen de la Infección Endodóntica?

RESUMEN: Los quistes periradiculares, tanto los de bolsillo como los verdaderos, son de origen inflamatorio; sin embargo, en la literatura ha existido una gran controversia asociada, en primer lugar, a la dependencia de la infección contenida dentro del sistema de conductos radiculares y, en segundo lugar, al tipo de tratamiento endodóntico llevado a cabo en este tipo de lesiones. Con el fin de dilucidar esta controversia se realizará una revisión a la literatura sobre quistes perira diculares donde se explicará cuál es la técnica más adecuada en el diagnóstico de quistes verdaderos y de bolsillo. Igualmente, se explicará la teoría de autosustentabilidad, así como el tratamiento endodóntico de grandes lesiones periradiculares asociadas a dichos quistes. Ahora bien, en la actualidad se ha demostrado que ambos quistes están asociados a infecciones contenidas en el sistema de conductos radiculares y son diferentes solamente en su morfología. Así mismo, se ha recomendado el tratamiento de conducto convencional en dientes con grandes lesiones asociadas a quistes.

ABSTRACT: Radicular cysts, either the pocket or the true cysts, are originated by an inflammation. However, in the literature, there has been great controversy surrounding, firstly, the dependence of the infection contained within the radicular conducts and, secondly, the kind of endodontic treatment performed in this sort of injury. In order to clarify this controversy, the literature concerning radicular cysts will be reviewed and it will be explained what technique is the most appropriate for diagnosing true cysts and pocket cysts. Likewise, the theory of self-sustaining, as well as the endodontic treatment for large radicular injuries associated to such cysts, will be further explained. Nonetheless, nowadays it has been demonstrated that both cysts are associated to infections contained within the system of radicular conducts and that they are only morphologically different. In addition, the root canal treatment has been recommended for teeth with great injuries associated to cysts.