Materiales bioactivos para restauraciones directas en dientes posteriores / Bioactive materials for direct restorations in posterior teeth

Se trata de paciente femenino de 22 años de edad, en quien se realizó una restauración en un molar siguiendo la filosofía de mínima intervención desde el diagnóstico hasta la obturación con un material bioactivo. Los objetivos del tratamiento fueron devolver la funcionalidad y estética de dicho molar, pero sobre todo brindar una protección a largo plazo mediante la liberación y recarga de iones de calcio, fosfato y flúor proporcionado por el material bioactivo (AU)

t is about a female patient of twenty-two years, in which a restoration was made in a molar following the philosophy of minimal intervention from diagnosis to filling with a bioactive material. The objectives of the treatment were to restore the functionality and aesthetics, but mainly to provide long-term protection through the release and recharge of calcium, phosphate and fluoride ions provided by the bioactive material used (AU)

Lesiones perirradiculares asociadas a primeros molares superiores tratados endodónticamente: estudio a través de tomografías computadas / Periradicular lesions associated with endodontically treated maxillary first molars: study through computed tomography

Objetivos: Estudiar con tomografías computadas de haz cónico (CBCT) las lesiones perirradiculares de primeros molares superiores tratados endodónticamente; evaluar la lo- calización y, en los que tenían lesión en la raíz mesiovestibu- lar (MV), evaluar la frecuencia del conducto MV2. Materiales y métodos: A partir de una muestra de 179 tomografías, que incluían primeros molares superiores, se seleccionaron y analizaron aquellas en las cuales estos ha- bían recibido un tratamiento endodóntico previo, presentaban lesiones perirradiculares y conservaban una restauración co- ronaria. Las variables analizadas fueron: la localización de áreas radiolúcidas compatibles con lesiones perirradiculares de origen endodóntico y la correlación entre diferentes loca- lizaciones y la calidad del tratamiento realizado (adecuado, defectuoso o sin tratamiento). Los datos fueron analizados mediante la prueba de chi-cuadrado y la prueba de Spearman. Resultados: De las 179 CBCT que incluían primeros molares superiores, 90 reunían las condiciones requeridas. La frecuencia de las lesiones perirradiculares fue significativa- mente mayor en la raíz MV al compararla con las raíces disto- vestibular y palatina (p<0,05). El conducto MV1 presentó un tratamiento adecuado en todos los casos. El conducto MV2 recibió un tratamiento adecuado en 4 casos (4,44%), defec- tuoso en 4 casos (4,44%) y no tratado en 82 casos (91,1%); con una diferencia estadísticamente significativa (p<0,05). Conclusiones: En la muestra analizada, la localización de lesiones perirradiculares postratamiento endodóntico en primeros molares superiores se encontró con mayor frecuencia asociada a la raíz mesiovestibular, donde en la mayoría de los casos el con- ducto MB2 no fue tratado o presentó un tratamiento defectuoso (AU)

Aim: To study with cone-beam computed tomography (CBCT) the periradicular lesions of maxillary first molars with endodontical treatment; to evaluate its localization and, in those with a mesiobuccal root (MB) injury, assess the fre- quency of the MB2 root canal. Materials and methods: From a sample of 179 tomog- raphies (CBCT) that included maxillary first molars, those in which they had received previous endodontic treatment, pre- sented periradicular lesions and had a coronary restoration were selected and analyzed. The analyzed variables were: localization of radiolucent areas compatible with periradic- ular lesions of endodontic origin and the correlation between different localizations and quality of the performed treatment (adequate, defective, or untreated). Data were analyzed by the chi-square test and the Spearman test. Results: Of the 179 CBCT that included maxillary first molars, 90 met the required conditions. The frequency of periradicular lesions was significantly higher in the MB root when compared with distobuccal and palatal roots (P<0,05). The MB1 canal presented an adequate treatment in all cas- es. The MB2 canal received adequate treatment in 4 cases (4.44%), a defective one in 4 cases (4.44%) and was untreated in 82 cases (91.1%). The differences among these frequencies were statistically significant (P<0.05). Conclusions: In the analyzed sample, the localization of periradicular lesions after endodontic treatment in maxillary first molars was associated more frequently with the mesio- buccal root in which in the majority of cases the MB2 canal was untreated or presented a defective treatment

Caries en primeros molares permanentes y factores asociados a esta en escolares de Acapulco / Caries in permanent first molars and associated factors with its in schoolchildren from Acapulco

Introducción: La caries es una de las enfermedades bucodentales más frecuentes y, por ser las primeras en emerger, los primeros molares permanentes son las piezas más susceptibles a esta afección. Objetivo: Estimar la prevalencia de caries y factores asociados a esta en los primeros molares permanentes en escolares de segundo grado de primaria. Métodos: Estudio transversal, en estudiantes de segundo grado en 17 de 67 escuelas públicas de Acapulco, Guerrero. Un cuestionario autoadministrado se utilizó para obtener datos sociodemográficos y hábitos de higiene dental. La caries y la presencia de placa dentobacteriana se midieron a través de índices epidemiológicos, el CPOD (diente cariado, obturado y perdido) y el O'Leary. Se estimó la razón de momios e intervalo de confianza de 95 por ciento, ajustada por conglomerado, como medida de la fuerza de asociación mediante análisis multivariado. Resultados: Se revisaron 3332 primeros molares permanentes, el 21 por ciento tuvo caries, el 6 por ciento tuvo obturaciones y el 1 por ciento ya se había extraído. El índice CPOD de caries grupal fue 0,27. Cinco factores estuvieron asociados a la caries de los primeros molares permanentes: higiene dental deficiente (RMa = 2,87), técnica de cepillado dental inadecuada (RMa = 1,70), tomar alguna bebida dulce antes de ir a dormir (RMa = 1,68), visitar al dentista (RMa = 0,67) y aplicación de flúor (RMa = 0,61). Conclusiones: La prevalencia de caries en los primeros molares permanentes fue 21 por ciento dentro del rango reportado en otros estudios. Fueron identificados cinco factores asociados a la caries: higiene dental deficiente, técnica de cepillado inadecuado, consumo de azúcares antes de dormir, visitas al dentista y aplicación de flúor. Estos factores orientan sobre qué medidas preventivas se deben promover en los escolares para la preservación de sus piezas dentales(AU)

Introduction: Caries is the most frequent oral disease and the first permanent molars are very susceptible to this condition because they are the first teeth to emerge. Objective: To estimate the prevalence of caries its associated factors in the first permanent molars in second grade primary school children. Methods: A cross-sectional study was carried out in second grade students in 17 out of 67primary public schools in Acapulco, Guerrero. We applied a self-administered questionnaire to obtain sociodemographic data and dental hygiene habits. Caries and the presence of dentobacterial plaque were measured through epidemiological indices, CPOD (decayed, blocked and lost tooth) and O'Leary index. The odds ratio and 95 percent confidence interval, adjusted by cluster, were estimated as a measure of strength of association through multivariate analysis. Results: We reviewed 3 332 permanent first molars, 21 percent had cavities, 6 percent had seals and 1 percent had already been removed. The CPOD index of group caries was 0,27. We found five factors associated with caries of the first permanent molars: deficient dental hygiene (RMa=2,87), inadequate tooth brushing technique (RMa=1,70), drinking a sweet drink before bedtime (RMa=1,68), visiting the dentist (RMa=0,67) and fluoride application (RMa=0,61). Conclusions: Prevalence of caries in the first permanent molars was 21 percent, within the range reported in other studies. Five factors associated with caries were identified: poor dental hygiene, inadequate brushing technique, consumption of sugars before going to sleep, visits to the dentist and application of fluoride. These factors guide what preventive measures should be promoted in schoolchildren for the preservation of their teeth(AU)

Influence of Monobloc/Le Fort III Surgery on the Developing Posterior Maxillary Dentition and Its Resultant Effect on Orthognathic Surgery.

BACKGROUND: Timing of frontofacial surgery for the syndromic craniosynostosis as it relates to various surgical risks has not been adequately studied. The purpose of this study was to investigate posterior dental complications of midface advancement in patients with syndromic craniosynostosis undergoing surgery at different ages and the effects on subsequent orthognathic surgery. METHODS: A retrospective chart review of patients with syndromic craniosynostosis treated with midface advancement (monobloc or Le Fort III) from 1999 to 2018 was carried out. Patient demographics, records, and imaging studies were reviewed. A subanalysis of those patients who were also treated with orthognathic surgery from 2014 to 2018 with imaging studies available for analysis was also performed. RESULTS: Thirty-seven patients met the inclusion criteria. Sixty-four percent of the patients had radiographic evidence of maxillary molar dental abnormality. Older age at the time of surgery was significantly associated with a lower odds of sustaining dental injury (OR, 0.55; p = 0.034). The odds of damaging second or third maxillary molars was significantly higher with a younger age at the time of surgery (p = 0.021 and p = 0.034). The odds of sustaining dental injury increased moving posteriorly, showing the risk of abnormal pattern of M3 greater than M2 greater than M1. Advanced age at the time of surgery was significantly associated with decreased odds of dental injury (OR, 0.55; p = 0.034). CONCLUSIONS: Damage to the developing permanent maxillary molars may affect orthodontic management, mastication, and potentially maxillary development. Delaying frontofacial surgery until development of the permanent maxillary dentition should be considered if other indications do not mandate earlier intervention.

Quiste bucal mandibular infectado bilateral: reporte de caso estudiado con CBCT / Bilateral mandibular infected buccal cyst: report of a case studied by CBCT

El quiste bucal mandibular infectado (QBMI), también conocido como quiste de bifurcación, es un quiste odontogénico inflamatorio poco frecuente y descripto por primera vez por Stoneman y Worth. Ha sido incluido en la clasificación de la OMS de quistes y tumores odontogénicos en 1992. Este quiste suele darse, específicamente, en pacientes entre 6 y 13 años, y su localización más frecuente son el primer y segundo molar permanente y, eventualmente, segundo premolar. Su fisiopatología sigue sin estar clara y se han propuesto múltiples teorías. Este quiste se observa como una inflamación en el vestíbulo del molar afectado. Los síntomas frecuentes son dolor en el área afectada y supuración, pero también muchos casos permanecen asintomáticos. Radiográficamente se describe como un área radiolúcida circunferencial. El quiste está revestido con un epitelio escamoso no queratinizado con infiltrado inflamatorio de células en el tejido conectivo. La mayoría de las características clínicas e histológicas son similares a las reportadas para los quistes paradentales, de ahí la importancia de un buen diagnóstico radiográfico complementario en base a tomografía computada de haz cónico. Los enfoques conservadores suelen ser el tratamiento de elección, con la enucleación del quiste y el seguimiento del diente afectado (AU)

Mandibular infected buccal cyst (MIBC), also known as bifurcation cyst; it is a rare inflammatory odontogenic cyst first described by Stoneman and Worth. It was included in the WHO classification of cysts and odontogenic tumours in 1992. It usually occurs, specifically, in patients between 6 and 10 years of age and its most frequent location is the first and second permanent molars, and eventually the second premolar. Its pathophysiology remains unclear and multiple theories have been proposed. This cyst is seen as an inflammation in the vestibule of the affected molar. Frequent symptoms are pain in the affected area and suppuration, but many cases remain asymptomatic. Radiographically it is described as a circumferential radiolucent area. The cyst is lined with a nonkeratinized squamous epithelium with an inflammatory cell infiltrate in the connective tissue. Most of clinical and histological characteristics are like those reported for paradental cysts, hence the importance of a good complementary radiographic diagnosis based on cone beam computed tomography. Conservative approaches are usually the treatment of choice, with enucleation of the cyst and monitoring of the affected tooth (AU)

Comparison of microcomputed tomography, cone beam tomography, stereomicroscopy, and scanning electron microscopy techniques for detection of microcracks on root dentin and effect of different apical sizes on microcrack formation.

The aim of the study was to compare different imaging methods in the diagnosis of microcracks on root dentin and to evaluate the frequency of dentinal microcracks observed after root canal preparation using the ProTaper Universal (PTU) system of different sizes. A total of 30 mandibular molars' mesial roots were scanned with microcomputed tomography (micro-CT) and cone beam computed tomography (CBCT) imaging methods before instrumentation. Root canal instrumentation was performed up to PTU F2 and F4 files. After instrumentation stages, the roots were scanned again with micro-CT and then with CBCT in same parameters. All roots were sectioned horizontally at 2, 4, 6, 8, and 10 mm from the apices of the specimens. The sections were imaged under a stereomicroscope. Finally, imaging of the sections was done by scanning electron microscopy (SEM). Statistical data analysis of instrumentation steps was performed using Friedman and Wilcoxon tests, and the data of imaging methods were analyzed using Kruskal-Wallis and Mann-Whitney U tests (p = .05). Instrumentation with the PTU system up to F2 and F4 files significantly increased the number of microcracks compared with preoperative samples according to micro-CT imaging (p < .05). For detecting microcracks on the root dentin, there were no statistically significant differences between micro-CT (43.9%) and stereomicroscopy (45.8%) (p < .05). SEM showed significantly higher percentage of microcracks (88.3%) (p > .05). No microcrack was observed using the CBCT method. There were no statistically differences between micro-CT and stereomicroscopy. SEM showed more dentinal microcracks while no microcrack was observed with CBCT.

A Mouse Model to Study Reparative Dentinogenesis.

Different animal models have been introduced recently to study the process of reparative dentinogenesis in response to injury-induced pulp exposure. Using a mouse model is advantageous over other animal models since mice can be genetically manipulated to examine specific cellular pathways and lineage trace the progeny of a single cell. However, enabling a standardized molar damage in mice is demanding due to the small size of the teeth compared to the available dental instruments. Here we describe a reproducible and reliable in vivo model that allows us to study dentinogenesis in the first maxillary mouse molar.

Effect of Reciproc blue, XP-endo shaper, and WaveOne gold instruments on dentinal microcrack formation: A micro-computed tomographic evaluation.

The purpose of this study was to evaluate and compare the effect of Reciproc Blue (RPCB), XP-endo Shaper (XPS), and WaveOne Gold (WOG) single-files on dentinal microcrack formation using micro-computed tomography (micro-CT). Twenty-four mesial roots (24 mesio-buccal and 24 mesio-lingual canals) of mandibular molar teeth were prepared using RPCB, XPS, and WOG files (n = 8/each group). The samples were scanned with micro-CT in the pre- and post-preparation. Then, before preparation and after preparation cross-sectional images of the teeth were evaluated to detect the presence of microcracks. For each group, the number of microcracks was calculated as a percentage rate. The data were statistically analyzed using McNemar at 5% significance level (p < .05). Dentinal microcracks were observed in 25.99% (2,103 of 7,813), 31.99% (2,482 of 7,758), and 36.66% (2,836 of 7,731) of cross-sectional images of the XPS, WOG, and RPCB groups, respectively. In all the groups, all the dentinal microcracks seen in the post-treatment cross-sectional images were present in the corresponding pre-treatment images. Within the limitations of this study, the XPS, WOG, and RPCB files did not cause new dentinal microcrack formation or propagation of existing dentinal microcracks.

Experimental furcal perforation treated with mineral trioxide aggregate plus selenium: immune response.

The aim of this study is to evaluate the expression of cytokines in response to mineral trioxide aggregate (MTA) plus selenium in germ-free mice with experimental furcal perforation. The first left maxillary molar was opened, and the furcal area was perforated and treated with post-MTA-Se (experimental group). The same surgical intervention was performed for the maxillary right first molar, which was treated with MTA (control group). Fifteen mice were sacrificed 7, 14, and 21 days after furcal perforation, and periapical tissue samples were collected. The mRNA expression levels of the cytokines TGF-ß, TNF-α, IFN-γ, HPRT, IL-10, IL-4, RANK, RANKL, IL-1, and IL-17 were assessed by using real-time polymerase chain reaction. In the experimental group, at 21-days post-MTA-Se sealing, the mRNA levels of TNF-α and IL-10 were upregulated compared with those in the control group (p < 0.05). Futher assessment revealed basal mRNA expression levels of IL-1α, IFN-γ, RANK, RANKL, IL-17A, IL-4, and TGF-ß, over long experimental times, in both the experimental and control groups (p > 0.05). In conclusion, MTA+Se sealing favoured increased expression of IL-10 and TNF-α at later time points (day 21).

Duration from Initial Symptoms to Diagnosis of Vertical Root Fracture in Dental Offices.

Diagnosing vertical root fracture (VRF) is difficult. Here, we retrospectively investigated the duration from initial symptoms to a definite diagnosis of VRF in dental offices. Data were collected on patients with VRF between July 2013 and June 2015. Initial symptoms were ascertained from clinical records. The focus was on the maxillary second premolars and mesial roots of the mandibular first molars, where VRF is most frequent. All VRF in the bilateral dentition was analyzed. Only cases in which the buccal-lingual plane of the root was fractured were included. Data from 31 dental offices revealed a total of 39 VRFs in the maxillary second premolars and 43 in the mandibular mesial roots of the first molars. The patients comprised 42 males and 40 females, and the average age was 59.7±11.6 years at initial onset of symptoms. The mean duration from initial symptoms to a definite diagnosis in the maxillary second premolars was 18.3±22.5 months, while that in the mandibular first molars was 16.1±17.8 months. The cumulative diagnostic rate was 48.7% at 12 months and 79.5% at 24 months in the maxillary second premolars, and 38.1% at 12 months and 86.0% at 24 months in the mandibular first molars. No significant difference was observed between tooth type. If VRF is suspected, doctors should explain the risks of tooth extraction and begin considering treatment options. The present results revealed that 80% of VRFs were diagnosed within 2 years of initial onset of symptoms.

Fractographic Analysis of a Split Tooth Presenting Radiographically as a Horizontal Root Fracture in an Unrestored Mandibular Second Molar.

INTRODUCTION: Spontaneously catastrophic fracture of intact unrestored molar teeth is not common. Nevertheless, cracks do occur that progress apically, resulting in the complete splitting of the tooth and root. This report describes a catastrophic fracture that occurred in an unrestored mandibular second molar resulting in a previously unreported combination of a longitudinal and horizontal root fracture, appearing radiographically as a single horizontal root fracture. METHODS: Tooth fragments were examined clinically, stereoscopically, and by scanning electron microscopy. Fractographic analysis was used to investigate the dynamics involved in fracture initiation, structural resistances encountered during progression of the fracture, and reasons for direction changes culminating in the unusual radiographic appearance. RESULT: The uniqueness of this report is that it describes fractographic evidence of factors contributing to the initiation and progression of an in vivo crack. It shows fracture markings that are evidence of the energy dissipation mechanisms. The topographic location of these markings confirmed that cracks occur in vivo in stages with different rates of progression. CONCLUSION: This analysis helps to explain why split teeth are uncommon and highlights some of the multitude of factors that have to coincide for a tooth to catastrophically fracture. The report describes the mechanism of fracture and should stimulate clinicians and researchers to investigate cracking of teeth by undertaking fractographic analysis of extracted cracked teeth.

Validation of a new experimental model of extrusive luxation on maxillary molars of rats: a histological study.

BACKGROUND/AIM: The aim of this study was to test and validate a new model of extrusive luxation trauma on maxillary first molars of rats. MATERIAL AND METHODS: Forty adult male rats (Rattus norvegicus albinus, Wistar; weight = 230-250 g), 45 days old, were divided into eight groups (n = 5): control groups, in which animals were not subjected to any procedure and waited 1 day (GC1D) or 3 days (GC3D) for euthanasia, and experimental groups, in which animals were subjected to forces of 1100cN, 1300cN, or 1500cN and waited 1 or 3 days for euthanasia (GT1100/1D, GT1100/3D, GT1300/1D, GT1300/3D, GT1500/1D, GT1500/3D). In animals of the experimental groups, trauma was produced by an extrusive force in maxillary first right molars. Four-micrometer serial cuts stained with hematoxylin and eosin (HE) were made. Descriptive microscopic analysis of first upper right molar and semi-quantitative analysis (scores 1 to 4) of intensity of acute and chronic inflammation and vascular changes in the periodontal ligament and active and inactive external root resorption were conducted. The distribution of scores in the groups was compared using the Freeman-Halton extension of Fisher's exact test. The significance level was 5%. RESULTS: It was observed that vascular disorders (bleeding) on the periodontal ligament became more evident with increasing extrusive force. CONCLUSIONS: This new method was capable of generating histological changes, proving its secure application in this research area. The 1500cN force produced more damage on the periodontal ligament. CLINICAL RELEVANCE: The validation of a new experimental method can produce more reliable evidence in further research.

Experimental furcal perforation treated with mineral trioxide aggregate plus selenium: immune response

Abstract The aim of this study is to evaluate the expression of cytokines in response to mineral trioxide aggregate (MTA) plus selenium in germ-free mice with experimental furcal perforation. The first left maxillary molar was opened, and the furcal area was perforated and treated with post-MTA-Se (experimental group). The same surgical intervention was performed for the maxillary right first molar, which was treated with MTA (control group). Fifteen mice were sacrificed 7, 14, and 21 days after furcal perforation, and periapical tissue samples were collected. The mRNA expression levels of the cytokines TGF-β, TNF-α, IFN-γ, HPRT, IL-10, IL-4, RANK, RANKL, IL-1, and IL-17 were assessed by using real-time polymerase chain reaction. In the experimental group, at 21-days post-MTA-Se sealing, the mRNA levels of TNF-α and IL-10 were upregulated compared with those in the control group (p < 0.05). Futher assessment revealed basal mRNA expression levels of IL-1α, IFN-γ, RANK, RANKL, IL-17A, IL-4, and TGF-β, over long experimental times, in both the experimental and control groups (p > 0.05). In conclusion, MTA+Se sealing favoured increased expression of IL-10 and TNF-α at later time points (day 21).

Characterization of consultations for odontogenic abscesses in a major Chilean hospital

OBJECTIVES: To characterize consultations for odontogenic abscesses at the dental and maxillofacial unit of the public emergency hospital in Santiago, Chile. METHODOLOGY: descriptive study, involving consecutive sampling of patients with diagnosis of odontogenic abscess, conducted between august and september 2016. descriptive statistics were performed to determine the frequency of diagnosis, affected tooth, sex and need for hospitalization. RESULTS: odontogenic abscesses accounted for 6.3 percent (n=414) of a total of 6,535 consultations. males represented 59 percent; 42 percent of odontogenic abscesses presented in molars and maxillary premolars. the vestibular space was the most frequently affected anatomical space (50 percent), associated in 53 percent of the cases to submucosal abscesses. ninety-eight per cent of patients were successfully treated on an outpatient basis, 2 percent required hospitalization, mainly associated to abscesses involving the deep submandibular space. CONCLUSION: odontogenic abscesses account for a low percentage of dental emergencies at the public emergency hospital in Santiago, Chile. most cases receive outpatient treatment.

A conservative management of iatrogenically damaged distal root of the mandibular second molar.

Trauma to the adjacent hard and soft tissue is the most common iatrogenic injury during extraction of the mandibular third molar. As every functional component of the dental arch is of prime importance in contemporary dental practice, the major concern must be in conserving the tooth and its structure as much as possible. The present case discusses the application of this conservative approach for management of iatrogenically damaged distal root of the mandibular second molar during extraction of impacted third molar, in which excessive guttering of alveolar bone and fractured apical third of distal root of 37 was observed radiographically. A conservative and noninvasive approach was successfully achieved to restore the damaged root by the bioactive material. Sealing of the remaining root with mineral trioxide aggregate allowed regeneration of soft and hard tissue around it.

Influence of Access Cavity Design on Root Canal Detection, Instrumentation Efficacy, and Fracture Resistance Assessed in Maxillary Molars.

INTRODUCTION: The aim of this study was to assess the influence of contracted endodontic cavities (CECs) on root canal detection, instrumentation efficacy, and fracture resistance assessed in maxillary molars. Traditional endodontic cavities (TECs) were used as a reference for comparison. METHODS: Thirty extracted intact maxillary first molars were scanned with micro-computed tomographic imaging at a resolution of 21 µm, assigned to the CEC or TEC group (n = 15/group), and accessed accordingly. Root canal detection was performed in 3 stages: (1) no magnification, (2) under an operating microscope (OM), and (3) under an OM and ultrasonic troughing. After root canal preparation with Reciproc instruments (VDW GmbH, Munich, Germany), the specimens were scanned again. The noninstrumented canal area, hard tissue debris accumulation, canal transportation, and centering ratio were analyzed. After root canal filling and cavity restoration, the sample was submitted to the fracture resistance test. Data were analyzed using the Fisher exact, Shapiro-Wilk, and t tests (α = 0.05). RESULTS: It was possible to locate more root canals in the TEC group in stages 1 and 2 (P < .05), whereas no differences were observed after stage 3 (P > .05). The percentage of noninstrumented canal areas did not differ significantly between the CEC (25.8% ± 9.7%) and TEC (27.4% ± 8.5%) groups. No significant differences were observed in the percentage of accumulated hard tissue debris after preparation (CEC: 0.9% ± 0.6% and TEC: 1.3% ± 1.4%). Canal transportation was significantly higher for the CEC group in the palatal canal at 7 mm from the apical end (P < .05). Canal preparation was more centralized in the palatal canal of the TEC group at 5 and 7 mm from the apical end (P < .05) and in the distobuccal canal of the CEC group at 5 mm from the apical end (P < .05). There was no difference regarding fracture resistance among the CEC (996.30 ± 490.78 N) and TEC (937.55 ± 347.25 N) groups (P > .05). CONCLUSIONS: The current results did not show benefits associated with CECs. This access modality in maxillary molars resulted in less root canal detection when no ultrasonic troughing associated to an OM was used and did not increase fracture resistance.

Autotransplantation of Mandibular Third Molar with Buccal Cortical Plate to Replace Vertically Fractured Mandibular Second Molar: A Novel Technique.

Tooth replacement often leads to inadequate vertical volume in the recipient site bone when a tooth has been extracted because of a vertical root fracture (VRF). This case report presents the autotransplantation of a mandibular third molar (tooth #32) with the attached buccal cortical plate to replace a mandibular second molar (tooth #31) diagnosed with a VRF. After extraction of tooth #31, the recipient socket was prepared based on the size measured in advance with cone-beam computed tomographic imaging. The precise and calculated osteotomy of the cortical bone of tooth #32 allowed for the exact placement of the donor tooth in the position of tooth #31. The total extraoral time was only 25 minutes. The block was fixed to the recipient socket with an osteosynthesis screw and splinted with a double resin wire for 8 weeks. At the 6-month follow-up, the screw was removed, and the stability of the tooth and the regeneration obtained throughout the vestibular area were confirmed. At the 2-year follow-up, the transplanted tooth was asymptomatic and maintained a normal bone level. Advantages of autotransplantation over dental implants include maintenance of proprioception, possible orthodontic movements, and a relatively low cost. This case report demonstrates that an autotransplantation of a third molar attached to its buccal cortical plate is a viable option to replace teeth with a VRF.

Pérdida prematura del primer molar permanente en niños de la escuela primaria "Antonio López". México. 2016 / First permanent molar premature lost in children of the "Antonio López" primary school. México. 2016

Introducción: el primer molar permanente es un diente fundamental al determinar el patrón de masticación durante toda la vida y desempeñar un papel primordial para desarrollar y mantener una oclusión apropiada. Objetivo: describir la pérdida prematura del primer molar permanente. Materiales y Métodos: se realizó estudio observacional, descriptivo, transversal en la escuela primaria "Antonio López Coloma" del Consejo popular México, del municipio Colón, provincia Matanzas, en el periodo comprendido de enero a marzo del 2015 en 169 niños las edades 6 a 11 años. Se estudiaron variables como: edad sexo, y localización del molar ausente. Resultados: el 3% de los estudiados perdió el primer molar permanente, el 40 % de niños con 11 años tuvo pérdida de este diente, las féminas representaron el 60 % de los estudiados. Conclusiones: los estudiados en la edad de 11 años con predominio del sexo femenino presentaron pérdida prematura del primer molar permanente, en los que resaltó el primer molar inferior izquierdo (AU).

Introduction: The first permanent molar is a fundamental tooth to determine the mastication pattern during the whole life, it is vital to develop and maintain a proper occlusion. Objective: describing the premature loss of the first permanent molar. Materials and Methods: an observational, descriptive and transversal study was carried out in the primary school Antonio López Coloma in the area of Mexico neighborhood in Colon municipality, Matanzas province, in the period from January to March 2015, in 169 children 6 to 11 years old. They were study variable, age, sex and the location of the missing tooth. Results: the 3 % of the students lost the first permanent molar, the 40 % of 11 years old boys loss this tooth. The girls represented the 60 % of the studied. Conclusions: The investigated mainly the female sex in the age of 11 lost the first permanent molar very early. The left lower first molar had the highest incidence (AU).

Prevalencia y algunos factores de riesgo de caries dental en el primer molar permanente en una población escolar de 6 a 12 años de edad / Incidence and risk factors of tooth decay on the first permanent molar in a schoolchildren population aged 6 to 12 years old

Introducción: La Organización Mundial de la Salud reporta que la caries en México afecta a 48 por ciento de los menores de 5 años y que 93 por ciento de los niños de 15 años la padecen. En conjunto se estima que 99 por ciento de la población ha tenido caries y que esta enfermedad es la causa más importante de la pérdida de dientes antes de los 35 años de edad. La pérdida principal la constituyen los primeros molares permanentes, estos órganos dentales acompañan a la dentición primaria en la boca de un niño transformando la oclusión de la primera dentición a la dentición mixta. El propósito de este trabajo fue identifi car la prevalencia y algunos factores de riesgo de caries en el primer molar permanente en una comunidad escolar del municipio de Tultitlán, Estado de México. Métodos: Estudio observacional, prolectivo, transversal y descriptivo en una población de 560 escolares con una media de edad de 9.0 (± 2.0), mediana de 9.0 (6-12 años). Se valoró la presencia de placa dentobacteriana con el índice O’Leary y la experiencia de caries con los índices CPOD y CPOS. Resultados: La prevalencia de caries en el primer molar permanente en la población de estudio fue de 25.6 por ciento, el valordel índice CPOS fue de 1.6 ± 2.7; CPOD de 1.0 ± 1.4; los más afectados son los molares inferiores en 30.6 por ciento (n = 343) con un CPOS 1.0 (± 1.7) vs. los superiores 20.5 por ciento (n = 226) con un CPOS de 0.6 (± 1.4). De los riesgos analizados, el factor tiempo de exposición a la PDB medido a través de la edad mostró que los escolares ≥ 8 años tienen 7.1 veces más riesgo de presentar caries en el PMP que los menores de esa edad, siendo esta diferencia clínica estadísticamente significativa (RM = 8.1; IC95 por ciento 4.4-14.7, p < 0.0001). Conclusiones: Nuestra población de estudio muestra una similitud en los índices de caries en la dentición permanente con la literatura científica.

Introduction: The World Health Organization reports that tooth decay inMexico aff ects 48% of children under 5 years of age and 93% of childrenunder 15. Overall it is estimated that 99% of the population has hadtooth decay and that this disease is the most important cause of tooth lossbefore age 35. The greatest loss is of the fi rst permanent molars, thesedental organs represent the primary dentition in the mouth of a child,transforming with its presence the primary occlusion in mixed. Therefore,the purpose of this study was to identify the prevalence and some risk factorsfor tooth decay in the fi rst permanent molar in a school community in themunicipality of Tultitlan, State of Mexico. Methods: An observational,prolective, transverse and descriptive study in a population of 560 studentswith a mean age of 9.0 (± 2.0), median of 9.0 (6-12 years), the presenceof dental plaque (biofi lm) was assessed with the O’Leary index and theexperience of tooth decay with the DMFT and DMF indexes. Results:The prevalence of tooth decay in the fi rst permanent molar in the studypopulation was 25.6%, the value of the DMF index was 1.6 ± 2.7; DMFTof 1.0 ± 1.4; the most aff ected were the lower molars with 30.6% (n = 343)with a DMF 1.0 (± 1.7) vs. the upper ones with 20.5% (n = 226) with aDMF of 0.6 (± 1.4). Of the risks analyzed, the factor «time of exposure toPDB¼ measured through age showed that, schoolchildren ≥ 8 years of ageare 7.1 times more likely to have tooth decay in the fi rst molar than childrenunder that age, this diff erence is clinically and statistically signifi cant (RM= 8.1, IC95% 4.4-14.7, p < 0.0001). Conclusions: Our study populationshows a similarity in the tooth decay indexes in permanent dentitionwith the one indicated in the scientifi c literature; of the risks analyzed,the exposure time to dental plaque (biofi lm) was the one that showed astatistically signifi cant diff erence.

Replacing Heavily Damaged Teeth by Third Molar Autotransplantation With the Use of Cone-Beam Computed Tomography and Rapid Prototyping.

This article describes the autotransplantation of third molars to replace heavily damaged premolars and molars. Specifically, this article reports on the use of preoperative cone-beam computed tomographic planning and 3-dimensional (3D) printed replicas of donor teeth to prepare artificial tooth sockets. In the present case, an 18-year-old patient underwent autotransplantation of 3 third molars to replace 1 premolar and 2 molars that were heavily damaged after trauma. Approximately 1 year after the traumatic incident, autotransplantation with the help of 3D planning and rapid prototyping was performed. The right maxillary third molar replaced the right maxillary first premolar. The 2 mandibular wisdom teeth replaced the left mandibular first and second molars. During the surgical procedure, artificial tooth sockets were prepared with the help of 3D printed donor tooth copies to prevent iatrogenic damage to the actual donor teeth. These replicas of the donor teeth were designed based on the preoperative cone-beam computed tomogram and manufactured with the help of 3D printing techniques. The use of a replica of the donor tooth resulted in a predictable and straightforward procedure, with extra-alveolar times shorter than 2 minutes for all transplantations. The transplanted teeth were placed in infraocclusion and fixed with a suture splint. Postoperative follow-up showed physiologic integration of the transplanted teeth and a successful outcome for all transplants. In conclusion, this technique facilitates a straightforward and predictable procedure for autotransplantation of third molars. The use of printed analogues of the donor teeth decreases the risk of iatrogenic damage and the extra-alveolar time of the transplanted tooth is minimized. This facilitates a successful outcome.