Natural canal deviation and dentin thickness of mesial root canals of mandibular first molars assessed by microcomputed tomography

Abstract The aim of this study was to assess the centralization and dentin thickness of mesial root canals of the first mandibular molars by microcomputed tomography (micro-CT). Material and methods: Ninety-nine mandibular molars of Vertucci's type IV canals were scanned by micro-CT. The mesiodistal deviation and centroid were assessed, in both mesiobuccal (MB) and mesiolingual (ML) canals, for the apical 4mm and the full canal length. Results: The dentin thickness was similar for both MB and ML canals. The narrowest thickness was in the distal wall of an MB canal (0.07mm), while the widest was found in the mesial wall of an MB canal (2.46mm). In centroid analysis, both the MB and ML canals exhibited deviations when compared to the root centroid, along the full canal length and the apical 4mm. For the MB canal, the mean deviation was 0.83mm (0.02 mm-2.30 mm) for the full canal and 0.18mm (0.01 mm-1.01 mm) for apical 4mm. Similarly, for the ML canal, the mean deviation measured 0.83 mm (0.05mm-3.99mm) for the full canal and 0.21 mm (0.01mm-1.01mm) for the apical 4 mm. Overall, deviations were observed towards the mesial of the roots, with 69% for MB and 57% for ML canals for the full canal, and 51% for MB canals within the 4 mm. The exception was the ML canal, which exhibited a higher deviation towards distal in the apical 4mm, accounting for 52% of cases. The dentin thickness was consistent between the mesial canals of mandibular molars. However, there is no centrality of mesial canals in their roots, with frequent deviation to mesial.

Resumo O objetivo deste trabalho foi avaliar a centralização e a espessura da dentina dos canais radiculares mesiais de primeiros molares inferiores por meio de microtomografia computadorizada (micro-CT). Material e métodos: Noventa e nove molares inferiores com canais tipo IV de Vertucci foram escaneados por micro-TC. O desvio mesiodistal e o centroide foram avaliados para os canais mesiovestibular (MB) e mesiolingual (ML), nos 4mm apicais e em todo o comprimento do canal. Resultados: A espessura da dentina foi semelhante para os canais MB e ML. A espessura mais estreita foi encontrada na parede distal de um canal MB (0,07mm), enquanto a mais larga foi encontrada na parede mesial de um canal MB (2,46mm). Na análise centroide, tanto o canal MB quanto o ML exibiram desvios quando comparados ao centroide da raiz, ao longo de todo o comprimento do canal e nos 4 mm apicais. Para o canal MB, o desvio médio foi de 0,83mm (0,02mm-2,30mm) para canal inteiro e 0,18mm (0,01mm-1,01mm) para o apical de 4mm. Da mesma forma, para o canal ML, o desvio médio mediu 0,83 mm (0,05 mm-3,99 mm) para o canal inteiro e 0,21 mm (0,01 mm-1,01 mm) para os 4 mm apicais. No geral, foram observados desvios em direção mesial das raízes, sendo 69% para canais MB e 57% para canais ML para canal inteiro, e 51% para canais MB dentro dos 4 mm. A exceção foi o canal ML, que apresentou maior desvio para distal nos 4mm apicais, representando 52% dos casos. A espessura da dentina foi consistente entre os canais mesiais dos molares inferiores. Entretanto, não há centralidade dos canais mesiais em suas raízes, com frequente desvio para mesial.

Morphological and anatomical aberrations induced by waterlogging in sugarcane

Aim: The present investigation was carried out to study root anatomy of sugarcane cultivars (CoLk 94184 and CoJ64) planted under waterlogged condition through Scanning Electron Microscopy (SEM). Methodology: Two sugarcane (Saccharum spp. hybrid) cultivars, CoLk 94184 and CoJ 64 were evaluated for changes in root anatomy in response to waterlogging during 2017-2018. For waterlogging treatment, crop was grown in deep plot which was waterlogged upto a depth of 1 m during active grand growth stage (monsoon season) along with untreated control plot. After three months of waterlogging, the plants were uprooted to study the root morphology and anatomy through SEM. Results: Waterlogged plants showed aerial root formation in both the cultivars but number and mass were higher in CoJ64. Aerenchyma was formed in the cortical region of both control and waterlogging roots but the size was relatively increased in waterlogged. Irregular and damaged surface cells with longer root hairs were observed in waterlogging treatment. Waterlogged roots exhibited cell distortion, loss of uniformity in endodermis and pericycle regions and higher number of metaxylem vessels. Interpretation: The study concluded that waterlogging treatment caused structural anomalies and induced anatomical and surface ultra-structural changes in both the cultivars, but the level of deformation was relatively higher in genotype CoJ 64, indicating sensitivity towards waterlogging as compared to cultivar CoLk 94184.

Comparisons of aortic anatomy between aortic stenosis and aortic regurgitation / 中国介入心脏病学杂志

Objective To compare aortic root anatomical characteristics between severe aortic valve stenosis (AS) and aortic regurgitation (AR) patients, and to provide useful information for transcatheter aortic valve replacement (TAVR) device designs and procedural techniques for treatment of AR. Methods Consecutive patients admitted between April 2014 to May 2016 with severe AS or AR and planned to undergo transcatheter aortic valve replacement were included. There were a total of 57 AR and 113 AS patients. All patients underwent multi-detector computed tomographic imaging and echocardiography examinations. Results The mean aortic annulus diameter in AR patients was slightly but significantly larger than AS patients[ (26.4±3.7) mm vs. (25.2±2.9) mm, P=0.001]. The mean diameters of the ascending aorta[ (38.3±6.9) mm vs. (33.9±6.7) mm, P<0.001]and Valsalva sinus[ (38.9±6.9) mm vs. (32.7±4.5) mm, P<0.001] in AR patients were larger than in AS patients. The left coronary ostia height was of no significant difference between the 2 groups [ (12.5±3.7) mm vs. (13.4±3.2) mm, P=0.08] and the right coronary ostia height was higher in the AR group than in the AS group [ (17.5±5.0) mm vs. (15.3±3.3) mm, P=0.001]. Conclusions The anatomical aortic root data from patients with AS or AR in the present study may provide useful information for transcatheter aortic valve replacement device designs and procedural techniques for treatment of AR.

Fused roots of maxillary molars: characterization and prevalence in a Latin American sub-population: a cone beam computed tomography study

OBJECTIVES: The upper molars generally have three roots; therefore, different combinations of fusion can occur, increasing the possibility of finding more complex root canal systems. The purpose of this study was to evaluate the prevalence and characterization of fused roots in first and second maxillary molars using cone-beam computed tomography (CBCT) in a Colombian population. MATERIALS AND METHODS: A total of 1274 teeth were evaluated, of which 534 were maxillary first molars and 740 were maxillary second molars. Axial sections were made at the cervical, middle, and apical levels to determine the prevalence of root fusion and the types of fusion. RESULTS: Overall, 43% of the molars (n = 551) presented some type of fused root. Root fusion was present in 23.4% of the maxillary first molars. The most frequent type of fused root was type 3 (distobuccal-palatal; DB-P) (58.9%). Root fusion was observed in 57.6% of the maxillary second molars, and the most prevalent type of fused root was type 6 (cone-shaped) (45.2%). Of the maxillary molars, 12.5% were classified as C-shaped. CONCLUSION: Within the limitations of this study, there was a high prevalence of fused roots in maxillary molars in the Colombian population, mainly in the maxillary second molars. In first molars, the most common type of fused root was type 3 (DB-P) and in second molars, the most common type was type 6 (cone-shaped). Additionally, molars with root fusion presented variation at different levels of the radicular portion, with implications for treatment quality.

Morfología radicular y mediciones apicales en primeros molares en una población maya / Root morphology and apical measurements of first molars in a Mayan population

El conocimiento preciso de la morfología radicular dental son claves para el éxito en las terapias endodónticas. El objetivo de este estudio fue evaluar las distintas variaciones de la morfología radicular y apical en primeros molares superiores e inferiores de una población maya moderna. Se observaron microfotografías provenientes de 80 primeros molares superiores e inferiores, presentadas en cortes transversales a 1 y 2,5 mm del vértice apical, así como de las porciones 1/3, 1⁄2, 2/3 del largo radicular y en la unión amelocementaria. Se determinó el número de raíces, conductos y configuración de Vertucci, así como forma y medidas de diámetro mayor y menor a 1 mm del vértice apical. El 90 % de primeros molares superiores reportó la presencia de 3 raíces y el 10 % mostró 2. En tanto que el total de primeros molares inferiores (100 %) reportó 2 raíces. En general, en las raíces mesiales prevaleció el Tipo II de Vertucci mientras que en las distales y palatinas la Tipo I. En el corte a 1 mm del vértice apical la forma redonda fue la de mayor prevalencia en los conductos de primeros molares superiores (44,5 %), seguida de la irregular (34,1 %) y la oval (21,4 %); mientras que en los primeros molares inferiores la más prevalente fue la irregular (54, 5 %), seguida de la redonda (23,9 %) y oval (21,6 %). Los diámetros mayor y menor de los conductos mesiales a 1 mm apical midieron 0,46 y 0,23 mm y 0,64 y 0,25 mm en molares superiores e inferiores respectivamente. La frecuencia de MB2 en primeros molares superiores fue del 77,8 %. Los conductos con mayor variabilidad fueron los mesiales. Se observó baja frecuencia de conductos ovales. Los diámetros mayores de los conductos mesiales en general, fueron superiores a 0,45 mm.

Accurate knowledge of dental root morphology is a key to success in endodontic therapies. The aim of this study was to evaluate the different variations of the root and apical morphology in upper and lower first molars of a modern Mayan population. Photomicrographs were taken from 80 upper and lower first molars, presented in cross sections at 1 and 2.5 mm from the apical vertex, as well as from the 1/3, 1⁄2, 2/3 portions of the root length and at the cementoenamel junction. The number of roots, canal and Vertucci`s configuration was determined, as well as the shape and measurements of the major and minor diameters at 1 mm from the apex. In this study 90 % of upper first molars reported the presence of 3 roots and 10 % showed 2, while the total lower first molars (100 %) reported 2 roots. In general, Vertucci`s Type II prevailed in the mesial roots while Type I was prevalent in the distal and palatal ones. In the 1 mm cut of the apical vertex, the round shape was the most prevalent in the canal of the first upper molars (44.5 %), followed by irregular (34.1 %) and oval (21.4 %); while in the first lower molars the most prevalent one was irregular (54.5 %), followed by round (23.9 %) and oval (21.6 %). The major and minor diameters of the mesial canals at 1 mm apical recorded 0.46 and 0.23 mm and 0.64 and 0.25 mm in upper and lower molars respectively. The frequency of MB2 in upper first molars was 77.8 %. The canals with greater variability were the mesial ones. Low frequency of oval canals was observed. The largest diameters of the mesial canal in general were greater than 0.45 mm.

Preparación Químico-mecánica del Tercio Apical en Micro-Cirugía Endodóntica. Una Revisión / Chemical-Mechanical Preparation of the Apical Third in Endodontic Micro-Surgery. A Review

Resumen El control micro-biológico y el selle tridimensional del conducto radicular son factores escenciales para alcanzar el éxito del tratamiento endodóntico. Actualmente la tasa de éxito para la micro-cirugía endodóntica es acerca del 92% cuando esta es realizada con el uso del microscopio como coadyudante en los procedimientos de conformación quimico-mecánica y selle del tercio apical. En consecuencia, el objetivo de este artículo fue hacer una revisión actualizada de todos los procedimientos clínicos retropreparación y desinfección del conducto radicular en micro-cirugía endodóntica, la cual fue soportada con la mejor evidencia disponible a la fecha.

Abstract The micro-biological control and three-dimensional sealing of the root canal are the determining factors to achieve the success of endodontic treatment. Currently, the success rate for endodontic microsurgery is 92% when using the microscope as a coadjuvant in the processes of chemical-mecanical preparation and filling of the apical third. Consequently, the objective of this article was to update all the clinical procedures of retropreparation and disinfection of the root canal in endodontic microsurgery, which was supported with the best evidence available to date.

Anatomía radicular, una mirada desde la micro-cirugía endodóntica: Revisión / Root anatomy, a view from the microsurgery endodontic: Review

Resumen El conocimiento de ia anatomía radicular de cada uno de los grupos de dientes, es un aspecto importante que contribuye juntos con otros aspectos clínicos, a un mejor resultado de los procedimientos de micro-cirugía endodóntica (MCE). Variaciones anatómicas entre individuos de una misma población, suscitan para el endodoncista, una evaluación diagnóstica detallada de cada caso en particular para facilitar el abordaje quirúrgico. El objetivo de esta revisión es realizar una descripción de la anatomía radicular y del sistema de conductos radiculares de los diferentes grupos de dientes y sus variaciones anatómicas según la literatura científica disponible a la fecha, que permitirá al clínico tener una visión más amplia y detallada, que podrá aplicar para la planeación y ejecución de los procedimientos de MCE.

Knowing the root anatomy of each groups of teeth, it is an important aspect that contributes with other clinical aspects, to a better outcome of the procedures in endodontic micro-surgery(MCE). Anatomical variations between individuals of the same population, arise in the endodontist, a detailed diagnostic evaluation of each particular case, which will facilitate the surgical approach. The objective of this review is to describe the anatomy and root canal system of different groups of teeth and anatomical changes according to available scientific literature to date, allowing the clinician to have a more comprehensive and detailed vision, you can apply for the planning and execution of procedures for MCE.

Bilateral two-rooted mandibular canines in the same individual: a case report / Caninos mandibulares birradiculares bilaterales en el mismo individuo: presentación de un caso

The normal anatomy of canines teeth comprises one root and one large canal centered through its axis; however some canines may present two roots and two canals. Thus, the knowledge of normal root canal anatomy and their variations is essential to minimize the possibility of occurrence of accidents during the development of dental treatments. In this report we describe a case of bilateral mandibular canines with two roots and two canals found radiographically in the same individual.

La anatomía normal de los dientes caninos comprende una raíz y un gran canal centrado a través de su eje, sin embargo algunos dientes canino pueden presentar dos raíces y dos canales. Así, el conocimiento de la anatomía normal de canal de la raíz y sus variaciones son esenciales para minimizar la posibilidad de accidentes durante el desarrollo de tratamientos dentales. En este informe se describe el caso de dientes caninos mandibulares con dos raíces y dos canales bilateralmente hallados radiográficamente en el mismo individuo.

Resistance induction for Meloidogyne incognita in sugarcane through mineral organic fertilizers

The effects of Coda Radimax (CR), Coda Humus-PK (CH) and Coda Vit (CV) on the induction of resistance for Meloidogyne incognita in sugarcane (Saccharum sp.) varieties (RB92579, RB863129, RB867515) through nematode reproduction, plant development and root anatomy analysis, emphasizing the differences of the lignin deposition, and cortex-vascular cylinder proportions were investigated. In 90 days after inoculation with eggs of M. incognita, CR reduced the number of eggs per root system in all the sugarcane varieties; CH and CV reduced eggs density in RB867515; CR increased stalk number in RB92579 and fresh weight of shoots in RB863129 and RB92579; CH increased plant height in RB92579 and fresh weight of shoots in RB92579 and RB867515, CV affected fresh weigh of shoots and roots of RB863129. All the tested compounds did not affect stalk diameter, number and dry weight of shoots. Cross-sections of roots showed no anatomical changes in the M. incognita inoculated tissues.

Este estudo investigou, em condições de casa de vegetação, os efeitos de três complexos organo-minerais (Coda Radimax, Coda Humus-PK e Coda Vit) na indução de resistência a Meloidogyne incognita em três variedades: RB92579, RB863129, RB867515 de cana-de-açúcar (Saccharum sp.), considerando-se a reprodução do nematóide, desenvolvimento das plantas e anatomia das raízes, com ênfase a diferenças na deposição de lignina e proporções do córtex e cilindro vascular. As avaliações foram efetuadas 90 dias após a inoculação com 5000 ovos de M. incognita por planta. Em relação à testemunha, Coda Radimax reduziu significativamente o número final de ovos por sistema radicular em todas as variedades. Coda Humus-PK e Coda Vit se mostraram eficientes em diminuir a densidade de ovos em RB867515, mas não em RB863129. Todos os compostos testados não afetaram o diâmetro do colmo, peso da biomassa seca da parte aérea e número de perfilho. Coda Radimax aumentou significativamente o número de colmos em RB92579 e a biomassa fresca da parte aérea em RB863129 e RB92579. Coda Humus-PK aumentou significativamente a altura da planta em RB92579 e a biomassa fresca da parte aérea em RB92579 e RB867515, enquanto Coda Vit afetou, significativamente, a biomassa fresca da parte aérea e raízes de RB863129. Fundamentando-se nas sessões transversais obtidas das raízes de cada variedade de cana observada sob microscópio ótico, não ocorreram modificações anatômicas significativas nos tecidos inoculados com M. incognita em relação aos tecidos sadios.

Effects of substrate water potential in root growth of Agave salmiana Otto ex Salm-Dyck seedlings

The objective of this study was to test the hypothesis that root of maguey (Agave salmiana Otto ex Salm-Dyck) seedlings reacts during the first 24 h to low substrate water potential (Yw), by anatomical modifications. Three-4 cm root length seedlings were planted in vermiculite for 24 h at Yw between -0.03 and -2.35 MPa. Root dimensions, proline content and anatomy were evaluated. Substrate ψw between -0.65 and -2.35 MPa did not significantly affect longitudinal root growth. However, proline content significantly increased from 1.6 to 2.1 emoles mg-1. Significant reductions of transverse root area (41 percent), thickness of mucilage covering the epidermis (47 percent), thickness of epidermis (between 15 and 46 percent), area of the parenchyma (between 35 and 41 percent) and number of vessels (up to 28 percent) were observed with Yw of -2.35 MPa. In contrast, thickness of xylem wall, diameter of xylem vessels and the number of cells of the cortex of the differentiation root region significantly increased (64, 17, and 97 percent, respectively). The anatomical changes associated with low substrate Yw indicate a net increase of root apoplatic paths; structures involved in water conduction increased their diameter under low substrate Yw conditions and anatomical changes occurred during the first 24 h of water stress.