Combined micro-apical surgery and vital pulp therapy in mandibular second molars with external root resorption caused by impacted teeth / 华西口腔医学杂志

OBJECTIVES@#This study aimed to establish a new treatment of the mandibular second molars with external root resorption caused by impacted teeth to preserve the affected teeth and their vital pulps.@*METHODS@#For mandibular second molars clinically diagnosed as external root resorption caused by impacted teeth, debridement and removal of the root at the resorption site via micro-apical surgery and direct capping of the pulp with bioactive material on the surface of the root amputation via vital pulp therapy were performed immediately after the impacted teeth were extracted.@*RESULTS@#The external root resorption of the affected tooth was ceased. It was asymptomatic with intact crown, normal pulp, periapical alveolar bone reconstruction, normal periodontal ligament, continuous bone sclerosis, and no periapical translucency in radiographic examination at the 1-year postoperative follow-up, thus showing good prognosis.@*CONCLUSIONS@#Simultaneous combination of micro-apical surgery and vital pulp therapy after extraction of impacted teeth could successfully preserve mandibular second molars with ERR caused by impacted teeth and their vital pulps.

Analysis of the mandibular molars root canals morphology. Study by computed tomography

Abstract This study aimed to analyze the root and root canal morphology of mandibular first and second molars using CBCT images. A total of 2,400 mandibular molars exams were selected from 600 patients aged between 18 and 75 years. The number of roots, number of root canals, and root canal configuration according to the Vertucci classification were verified. Overall, 94.92% of mandibular first molars and 90.17% of mandibular second molars had two separate roots. Among the biradicular molars, the first molars showed a greater incidence of type IV canals in the mesial root and type I in the distal root. In the second molars, the most common canal form was type IV in the mesial root and type I in the distal root. In the triradicular molars, the type IV and type I configurations were the most common in the mesial root of the first molar and second molar, respectively. In both triradicular molars, there was a prevalence of type I canal in the distal and DL roots. Statistical analysis was performed at a significance level of 0.05. The number of roots was correlated with gender (Spearman test), and the canal's configuration with gender and bilaterality (Wilcoxon test). The subpopulation studied has a high incidence of bilateral symmetry and mandibular molars with two roots with two distinct mesial canals and one distal canal. The bilateral configuration is possible to estimate the number of canals, especially in images that are difficult to visualize, such as atresic canals.

A cone-beam computed tomographic study of root and root canal morphology of primary maxillary and mandibular second molars in Indian Children An in vitro study

Introduction: The root canal system in primary molars is considered to be complex. The aim of the present study was to assess the morphology of roots and root canals of primary maxillary and mandibular second molars using the cone-beam computed tomography (CBCT). Materials and Methods: From a total of 104 collected primary maxillary and mandibular molars (51 maxillary second molars and 53 mandibular second molars), 60 teeth (30 each of maxillary and mandibular second molars) were selected randomly and accordingly assigned into two groups: MAX2M (primary maxillary second molars) and MAN2M (primary mandibular second molars). CBCT was used to assess the number of roots and root canals, length of root, mesiodistal and buccolingual width of the canal, shape of the canal, and intercanal communications. Descriptive statistical analysis was performed using the SPSS software version 17.0. Results: The mandibular second molars showed the presence of two roots in 27 sample molars while the presence of three roots was observed in three MAN2M group. In these molars, all three roots exhibited Type I root canal configuration. The maxillary second molars exhibited three roots. A total of nine intercanal communications were seen in MAX2M group, whereas two communications were seen in MAN2M group. The palatal root in MAX2M group was more angulated (mean value: 127.21 ± 9.10) as compared to mesial (mean value: 95.39 ± 8.64) and distal roots (114 ± 11.24). Conclusion: The comprehensive knowledge of root and canal morphology of primary molars and anatomic variations is essential for successful endodontic therapy.

Bilaterality and symmetry of c-shaped mandibular second molars in a Mexican Maya and non-Maya population: a CBCT in vivo study / Bilateralidad y simetría de los segundos molares mandibulares en forma de c en una población mexicana Maya y no Maya: estudio in vivo mediante CBCT

SUMMARY: The objective of this study was to evaluate the bilaterality and symmetry in C-shaped mandibular second molars in Mexican Maya and non-Maya populations using cone-beam computed tomography (CBCT). Five-hundred-twenty-five CBCT scans of patients with left and right mandibular second molars were analyzed to determine the prevalence and bilaterality. The teeth were assessed for the presence of C-shaped root canals, according to Fan et al. (2004) criteria. The sample was subdivided by ethnicity, sex, unilateral/bilateral presence, side of the longitudinal groove, and the C-shaped root canal configuration and symmetry, at the cervical, middle, and apical cross- sections of the root. C-shaped mandibular second molars were present in 24.95% of the individuals. Most (60.30%) of those showing this trait had it bilaterally. When comparing by ethnicity, sex, and side, we detected no significant differences. The vast majority (97.33%) presented the groove along the lingual side. The C3 was the most prevalent configuration in the overall sample, while in the Maya group, the C1 was the most common configuration. When analyzed by sex and ethnic group, the non-Maya females tended to deviate from the other groups in terms of bilaterality. Overall, 55.70% of bilateral C-shaped mandibular second molars were also symmetric in the three radicular thirds. The prevalence of C-shaped mandibular second molars was similar to that reported for northernAsian populations, which is consistent with the evolutionary origins of Native American populations. Most of the sample showed bilaterality and half were symmetric. Clinicians must be aware of the ethnic background of their patients and consider the possible variations to do more predictable root canal treatments.

RESUMEN: El objetivo de este estudio fue evaluar la bilateralidad y simetría de los segundos molares mandibulares en forma de C en una población Mexicana Maya y no-Maya mediante tomografía computarizada de haz cónico (CBCT). Material and Métodos: Se analizaron quinientos veinticinco tomografías de pacientes con segundos molares mandibularesderecho e izquierdo para determinar la prevalencia y bilateralidad. Los dientes fueron evaluados según la presencia de conductos en forma de C de acuerdo a los criterios de Fan et al. La muestra fue subdividida por etnicidad, sexo, presencia bilateral/unilateral, lado del surco y configuración y simetría de los conductos en los cortes transversales cervical, medio y apical. Los segundos molares mandibulares en forma de C estuvieron presentes en el 24.95 % de los individuos. La mayoría (60.30%) de los que mostraron este rasgo lo hicieron de forma bilateral. El comparar por etnicidad, sexo y lado, no se encontraron diferencias estadísticamente significativas. La gran mayoría (97.33%) presentó el surco por lingual. C3 fue la configuración más prevalente en la muestra general, mientras que en el grupo Maya el C1 fue la más común. El análisis por sexo y grupo étnico arrojó que las mujeres no Mayas tendieron a desviarse de los otros grupos en términos de bilateralidad. El 55.70% de los segundos molares mandibulares bilaterales fueron simétricos en sus tres tercios radiculares. La prevalencia de los segundos molars mandibulares en forma de C fue similar a la reportada para las poblaciones del norte de Asia, lo cual es consistente con los orígenes evolutivos de las poblaciones nativas americanas. La mayor parte de la muestra presentó el rasgo de forma bilateral y la mitad de éstos fueron simétricos. Los odontólogos deben tomar en cuenta el origen étnico de sus pacientes y considerar las posibles variaciones para realizar tratamientos endodónticos más predecibles.

Estado periodontal del segundo molar adyacente al tercer molar mandibular / Periodontal status of the second molar adjacent to the third mandibular molar

Los terceros molares tienen un patrón de erupción inusual. Estudios sugieren que, debido a la posición y angulación de estos, se pueden presentar diversas patologías en los molares adyacentes, tales como problemas periodontales y aparición de caries distales. El objetivo de este trabajo es describir el estado periodontal de los segundos molares mandibulares adyacentes a terceros molares mandibulares. Para ello se realizó un estudio descriptivo transversal. Se trabajó con una muestra de 277 pacientes que acudieron a la clínica odontológica de la UCSG para realizarse extracciones de terceros molares en el período A-2018. Se realizó un examen clínico intraoral en donde se observaron las siguientes variables: profundidad de sondaje, estado gingival y presencia de caries en segundos molares mandibulares. Además, se revisó las radiografías panorámicas de los pacientes para determinar la posición del tercer molar mandibular y el nivel de la cresta ósea distal de los segundos molares. Los resultados mostraron que la profundidad del sondaje por distal de los segundos molares mandibulares revisados fue normal (de 1 a 3mm) en el 31% de los casos, en tanto que en el 69% se encontraron profundidades mayores a 3mm. Con respecto a la presencia de pérdida ósea en estas piezas, en el 43% de los casos no hubo pérdida, en el 35% de los casos hubo pérdida leve, el 22% presentó pérdida moderada y solo un 1% tuvo pérdida severa. La presencia de terceros molares mandibulares afecta de forma significativa el estado periodontal del segundo molar adyacente, pudiendo generar bolsas periodontales, pérdidas óseas y caries en la zona distal de estos.

Third molars have an unusual eruption pattern. Studies suggest that, due to the positionand angulation of these, various pathologies could occur in the adjacent molars, such as periodontal problems and the appearance of distal caries. The objective of this work is to describe the periodontal status of mandibular second molars adjacent to mandibular third molars. For this, a descriptive transversal study was carried out. We worked with a sample of 277 patients that went to the Dental UCSG Clinic to have their third molars extracted in the period A-2018. An intraoral clinical examination was performed, and the following variables were observed: probing depth, gingival state, and presence of caries in mandibular second molars. In addition, panoramic x-rays of the patients were reviewed to determine the position of the third mandibular molar and the level of the distal bone crest of the second molars. The results showed that the depth of distal probing of the mandibular second molars were normal (from 1 to 3mm) in 31% of the cases, while in 69% depths greater than 3mm were found. Regarding the presence of bone loss, in 43% of the cases there was no loss, in 35% of the cases there was a slight loss, 22% presented moderate loss and only 1% had severe loss. The presence of mandibular third molars significantly affects the periodontal status of theadjacent second molar, which can lead to periodontal pockets, bone loss and caries in their distal area.

Clinical application of molar uprighting for impacted mandibular second molars / 口腔疾病防治

Objective @#To investigate the effect of the clinical application of molar uprighting in the treatment of impacted mandibular second molars.@*Methods@# A total of 16 cases of impacted mandibular second molars were chosen, and the impacted molars were treated with straight wire appliances and molar uprighting. Before and after treatment, the vertical angle of the molar, the height of the distal buccal tip, the height of the distal buccal tip of the anchorage molar, the depth of the periodontal pocket and the height of the alveolar bone were measured. Moreover, the treatment cycles of the third molar extraction group, the premolar group and the nonextraction group were compared.@*Results @#All impacted molars responded well to treatment. The vertical time of impacted molars was (1.34 ± 0.45) months, (2.20 ± 0.57) months, and (2.30 ± 0.45) months in the third molar extraction group, the premolar extraction group and the nonextraction group, respectively. The treatment time of the third molar extraction group was shorter than that of the other two groups, and the difference was statistically significant (P < 0.05). After treatment, the inclination of impacted second molars increased by (25.94 ± 8.85)°, the elongated distal buccal tip was depressed by (1.00 ± 1.48) mm, the depth of the proximal and middle periodontal pocket of impacted molars decreased by (1.21 ± 1.03) mm, and the height of the alveolar bone of the proximal and middle adjacent surfaces of impacted second molars increased by (4.57 ± 1.45) mm; these differences were statistically significant (P < 0.05). There was no significant difference in the height of the distal buccal tip of the first molar before and after treatment (P > 0.05).@*Conclusion @#Molar uprighting is an efficient, reliable, and convenient method that can shorten the treatment period. Extraction of crowded third molars is beneficial for the vertical and periodontal health of impacted second molars.

Prevalence of impacted permanent mandibular second molars in South Indian population: A cross-sectional study.

Aims: The aim of this study is to retrospectively determine the prevalence of impacted second molars and associated dental and radiographic findings in South Indian population. Settings and Design: Cross-sectional design. Materials and Methods: Dental records of 4976 patients depending on the selection criteria from various dental clinics in South India were retrospectively analyzed in this study. All selected radiographs and records were examined by the two authors. The angle of impacted second molars was also recorded on panoramic radiographs. Data were tabulated and analyzed. Results: The prevalence of impacted second mandibular molars was found to be 0.16%. In seven cases, the impaction was unilateral with three on the left and four on the right, and in one case, it was bilateral. The prevalence was found to be more in females than males. The angle of impaction was found to range from 19° to 80°. Conclusions: Although the prevalence of impacted second molars is low, it is crucial to diagnose early for optimal treatment.

Asymmetry in mesial root number and morphology in mandibular second molars: a case report

Ambiguity in the root morphology of the mandibular second molars is quite common. The most common root canal configuration is 2 roots and 3 canals, nonetheless other possibilities may still exist. The presence of accessory roots is an interesting example of anatomic root variation. While the presence of radix entomolaris or radix paramolaris is regarded as a typical clinical finding of a three-rooted mandibular second permanent molar, the occurrence of an additional mesial root is rather uncommon and represents a possibility of deviation from the regular norms. This case report describes successful endodontic management of a three-rooted mandibular second molar presenting with an unusual accessory mesial root, which was identified with the aid of multiangled radiographs and cone-beam computed tomography imaging. This article also discusses the prevalence, etiology, morphological variations, clinical approach to diagnosis, and significance of supernumerary roots in contemporary clinical dentistry.

Bilateral three-rooted primary lower molars.

The dental literature contains a small number of reports of primary multi-rooted anomalies. Among these reports the majority are regarding three-rooted primary mandibular second molar anomalies. The presence of bilateral three-rooted primary mandibular first and second molars is uncommon. There have been no reports of three-rooted primary molars from India. Here, we present a case of an 8-year-old boy with bilateral three-rooted primary mandibular first and second molars.

A extração de segundos molares superiores para o tratamento da Classe II / Extraction of upper second molars for treatment of Angle Class II malocclusion

Este trabalho tem por objetivo apresentar uma abordagem alternativa para o tratamento ortodôntico das más oclusões de Classe II. Através de uma revisão da literatura, verificou-se que a extração de segundos molares superiores demonstrou ser uma alternativa viável para o tratamento desse tipo de má oclusão. Essa opção terapêutica possibilita maior rapidez na distalização dos primeiros molares com menor necessidade de cooperação por parte do paciente. Porém, a análise do grau de formação, posição intraóssea e morfologia do terceiro molar deve ser cuidadosamente realizada para proporcionar o correto posicionamento do mesmo no lugar do segundo molar extraído. Dois casos clínicos apresentarão a sequência do diagnóstico e tratamento com essa mecânica, exibindo resultados adequados dos pontos de vista funcional e estético.

The purpose of this article is to present an alternative approach to the orthodontic treatment of Angle Class II malocclusion. According to a literature review it was observed that the extraction of upper second molars has proven to be a viable alternative for the treatment of this type of malocclusion. This therapeutic option enables faster first molar retraction and requires less patient compliance. However, the level of development, intraosseous position and morphology of the third molar should be carefully evaluated to ensure its correct positioning in place of the extracted second molar. Two clinical case reports will demonstrate that the sequence of diagnosis and treatment used with this mechanics yields satisfactory functional and aesthetic results.

Clinical Study of the Symmetry of C-shaped Root Canal System in Mandibular Second Molars / 医学研究杂志

Objective To determine the prevalence of symmetry of C shaped root canal system in mandibular second molars.MethodsA total of 70 madibular second molars with C shaped root canal system to be considered as needing root canal therapy were included in this study,of which 68 contralateral X ray apical films were obtained.The symmetry of the root and the root canal system was analyzed using magnifying glass.ResultsOf the 68 mandibular second molars with C shaped root canal system diagnosed clinically,62 cases with C shaped root canal system bilaterally,with the prevalence 91.18%.ConclusionThe anatomic feature of mandibular molars with C shaped root canal system is complicated,and the prevalence of symmetry is very high,which is in favor of estimating the anatomic feature from contralateral tooth.

Root canal obturation of C-shaped canals in mandibular second molars:An in vitro study by three techniques / 实用口腔医学杂志

Objective:To compare the sealing ability and marginal adaptation of three obturation techniques when used in root canal obsturation of c-shaped canals of mandibular second molars. Methods:Twenty-one extracted mandibular second molars with C-shaped canals were randomly divided into three groups. After instrumentation, the canals were filled using three different techniques: ObturaⅡ(group A), cold lateral condensation (group B) and Thermafil (group C). Then, gaps,obturated lateral canals and reticular apical triangles on the X-ray were counted. After dyeing for 7 days in the ink, dyeing lines were measured to reflect the microleakage. The percentages of gutta-percha, sealer and gaps on the root canal surface were determined by analyzing the images of 3 sections per tooth. Results:The reticular apical triangles were most frequently observed in group C(P

Anatomical character of root canals in one-rooted mandibular second molars / 实用口腔医学杂志

Objective:To investigate the root canal anatomy of one-rooted mandibular second molars. Methods:The root canals of 18 one-rooted mandibular second molars were visualized on radiographs and clinical examination, some specimens were cut at the mid-root level and observations were made on the coronal root section. Teeth with C-shaped canal system were categorized by using a modification of Melton classification.Results:12 molars exhibited C-shaped canals.2 molars were classified as category Ⅰ,5 as Ⅱ and another 5 cases as Ⅲ.Conclusions:C-shaped canals in mandibular second molars vary in canal number and shape.