Root resorption factors associated with orthodontic treatment with fixed appliances: A systematic review and meta-analysis.

External apical root resorption (EARR) is a serious complication that should be avoided during orthodontic treatment; this pathology depends on multiple factors. Data from clinical studies should be assessed to determine the influence these factors have on the development of EARR. This systematic review aims to compare EARR produced by different factors (orthodontic systems, dental trauma, and dental vitality). The protocol was registered on the PROSPERO database. The search was performed on 5 databases. Accepted study designs included randomized controlled trials, nonrandomized clinical trials, and observational studies. Full-text articles from clinical studies of EARR associated with orthodontic treatment in English, Spanish, or Portuguese with no publication date restrictions were selected. Data from the studies, such as age, population, study groups, and outcome measures, were recorded. Multiple meta-analyses were performed with data from the included studies. Evidence suggests that EARR induced by orthodontic treatment is similar, regardless of the technique used. Evidence of the effect of previous dental trauma on EARR during orthodontic treatment is limited. There is less EARR associated with orthodontic treatment in endodontically treated teeth than in vital teeth. These conclusions should be considered with caution due to the low certainty of the evidence.

Vertical root fractures in endodontically-treated teeth: A retrospective analysis of possible risk factors.

AIM: The prevalence of vertical root fractures (VRF) ranges from 2% to 20%, and is associated with endodontically-treated teeth (ETT). The aim of the present study was to analyze clinically and radiographically, at different intervals of time, some of the risk factors present in ETT that developed VRF. METHODS: A classification model according to time measured the follow-up period of three groups. A match was made for times of occurrence (cases) and follow up (controls). An odds ratio (OR) test and a logistic regression model set at 95% confidence interval (CI) established the VRF probability when different clinical factors (patient, tooth, and endodontic or restorative treatment) were present. RESULTS: The sample was composed of 197 ETT (41 cases and 156 controls). A classification model set the trend, thus defining three groups: group 1 (1-4 years of follow up): endodontic retreatment (OR: 8.01, 95% CI: 1.85-37.90, P=.0014), indirect restoration (OR: .202, 95% CI: .036-.979, P=.05); group 2 (5-8 years of follow up): primary treatment (OR: .052, 95% CI: .002-.680, P=.044) and the 'single tooth' category (OR: .042, 95% CI: .002-.453, P=.02) demonstrated a significant association with VRF; and group 3 (>9 years of follow up): no association. CONCLUSION: Endodontic retreatment had the highest risk association for VRF after 1-8 years of follow up. Indirect and individual restorations were not significantly associated with VRF.

Complejidad del tratamiento endodóntico, según factores asociados / Endodontic treatment complexity and associated factors

Introducción: la clasificación de la complejidad de la terapia endodóntica permite estimar factores que pueden interferir su éxito. Objetivo: determinar la correspondencia entre la duración del tratamiento pulporadicular y la complejidad asignada, según el Formulario de Evaluación de las Dificultades del Tratamiento Endodóntico. Métodos: se realizó un estudio descriptivo longitudinal prospectivo con un muestreo por conglomerado bietápico; quedaron incluidos 82 pacientes. Fue aplicado un modelo que recoge factores asociados a la complejidad del tratamiento endodóntico, mediante el interrogatorio, examen clínico y radiográfico. Los datos fueron procesados con el software estadístico SPSS versión 15.0. Se emplearon técnicas de la estadística descriptiva (frecuencias absolutas y porcentajes). Las variables empleadas fueron: edad, sexo, antecedentes patológicos, anestésicos, conducta del paciente, apertura bucal, reflejo nauseoso, complicaciones, dificultad radiográfica, diagnóstico, posición en el arco, inclinación y rotación dentaria, morfología coronaria, ápice radicular, alteración del número de raíces, bifurcación, visibilidad y tamaño de los conductos, acceso cameral, presencia de calcificaciones, reabsorción, enfermedad periodontal y complejidad del tratamiento. Resultados: en 80,8 por ciento de los pacientes, la categoría de elevada dificultad el tratamiento tuvo una duración entre 6 y 10 semanas. El dolor moderado o intenso e inflamación extendida se presentó en 29,3 por ciento de los casos. Dentro de los factores relacionados con el diagnóstico y el tratamiento se observaron las restauraciones extensas, la moderada dificultad en la obtención e interpretación de la imagen radiográfica, así como la inclinación dentaria moderada y los conductos visibles, pero reducidos en 23,2 por ciento, 22,0 por ciento, 20,7 por ciento y 19,5 por ciento, respectivamente. Conclusiones: la duración de la terapia aumenta en correspondencia con la complejidad que asigna el ...(AU)

Introduction: classifying the complexity of endodontic therapy makes it possible to identify factors which may interfere with its success. Objective: determine the correspondence between the duration of root canal treatment and the complexity assigned to it on the Endodontic Case Difficulty Assessment Form. Methods: a prospective longitudinal descriptive study was conducted based on two-staged cluster sampling. The resulting study group was composed of 82 patients. A form was used which lists the factors associated with the complexity of endodontic treatment, collected through interviews and clinical and radiographic examination. Data were processed with the statistical software SPSS version 15.0. Use was made of descriptive statistics techniques (absolute frequencies and percentages). The variables studied were age, sex, pathological antecedents, anesthetics, patient behavior, mouth opening, gagging, complications, radiographic difficulty, diagnosis, position in the arch, dental inclination and rotation, crown morphology, root apex, alteration in the number of roots, bifurcation, duct visibility and size, chamber access, presence of calcifications, resorption, periodontal disease and complexity of the treatment.Results: in 80.8 percent of the patients, the category of high treatment difficulty had a duration of 6 to 10 weeks. Moderate or intense pain and extended swelling were present in 29.3 percent of the cases. The following factors related to the diagnosis and treatment were observed: extensive restorations, moderate difficulty to obtain and interpret the radiographic image, moderate dental inclination and visible ducts, occurring in 23.2 percent, 22.0 percent, 20.7 percent and 19.5 percent of the cases, respectively.Conclusions: treatment duration increases in keeping with the complexity assigned by the form. It is important to evaluate the factors associated with treatment difficulty to foster a more reasonable approach to each specific situation(AU)

Complejidad del tratamiento endodóntico, según factores asociados / Endodontic treatment complexity and associated factors

Introducción: la clasificación de la complejidad de la terapia endodóntica permite estimar factores que pueden interferir su éxito. Objetivo: determinar la correspondencia entre la duración del tratamiento pulporadicular y la complejidad asignada, según el Formulario de Evaluación de las Dificultades del Tratamiento Endodóntico. Métodos: se realizó un estudio descriptivo longitudinal prospectivo con un muestreo por conglomerado bietápico; quedaron incluidos 82 pacientes. Fue aplicado un modelo que recoge factores asociados a la complejidad del tratamiento endodóntico, mediante el interrogatorio, examen clínico y radiográfico. Los datos fueron procesados con el software estadístico SPSS versión 15.0. Se emplearon técnicas de la estadística descriptiva (frecuencias absolutas y porcentajes). Las variables empleadas fueron: edad, sexo, antecedentes patológicos, anestésicos, conducta del paciente, apertura bucal, reflejo nauseoso, complicaciones, dificultad radiográfica, diagnóstico, posición en el arco, inclinación y rotación dentaria, morfología coronaria, ápice radicular, alteración del número de raíces, bifurcación, visibilidad y tamaño de los conductos, acceso cameral, presencia de calcificaciones, reabsorción, enfermedad periodontal y complejidad del tratamiento. Resultados: en 80,8 por ciento de los pacientes, la categoría de elevada dificultad el tratamiento tuvo una duración entre 6 y 10 semanas. El dolor moderado o intenso e inflamación extendida se presentó en 29,3 por ciento de los casos. Dentro de los factores relacionados con el diagnóstico y el tratamiento se observaron las restauraciones extensas, la moderada dificultad en la obtención e interpretación de la imagen radiográfica, así como la inclinación dentaria moderada y los conductos visibles, pero reducidos en 23,2 por ciento, 22,0 por ciento, 20,7 por ciento y 19,5 por ciento, respectivamente. Conclusiones: la duración de la terapia aumenta en correspondencia con la complejidad que asigna el formulario. La evaluación de los factores asociados a la dificultad del tratamiento es importante para propiciar una conducta más razonable ante cada situación específica(AU)

Introduction: classifying the complexity of endodontic therapy makes it possible to identify factors which may interfere with its success. Objective: determine the correspondence between the duration of root canal treatment and the complexity assigned to it on the Endodontic Case Difficulty Assessment Form. Methods: a prospective longitudinal descriptive study was conducted based on two-staged cluster sampling. The resulting study group was composed of 82 patients. A form was used which lists the factors associated with the complexity of endodontic treatment, collected through interviews and clinical and radiographic examination. Data were processed with the statistical software SPSS version 15.0. Use was made of descriptive statistics techniques (absolute frequencies and percentages). The variables studied were age, sex, pathological antecedents, anesthetics, patient behavior, mouth opening, gagging, complications, radiographic difficulty, diagnosis, position in the arch, dental inclination and rotation, crown morphology, root apex, alteration in the number of roots, bifurcation, duct visibility and size, chamber access, presence of calcifications, resorption, periodontal disease and complexity of the treatment. Results: in 80.8 percent of the patients, the category of high treatment difficulty had a duration of 6 to 10 weeks. Moderate or intense pain and extended swelling were present in 29.3 percent of the cases. The following factors related to the diagnosis and treatment were observed: extensive restorations, moderate difficulty to obtain and interpret the radiographic image, moderate dental inclination and visible ducts, occurring in 23.2 percent, 22.0 percent, 20.7 percent and 19.5 percent of the cases, respectively. Conclusions: treatment duration increases in keeping with the complexity assigned by the form. It is important to evaluate the factors associated with treatment difficulty to foster a more reasonable approach to each specific situation(AU)

Tooth loss in individuals under periodontal maintenance therapy: 5-year prospective study.

BACKGROUND AND OBJECTIVE: Tooth loss (TL), one of the most visible results of the evolution of periodontitis, causes physiological and psychological impacts on a patient's life. This prospective study aimed to evaluate the incidence, underlying reasons and influence of risk predictors for the occurrence of TL in a program of periodontal maintenance therapy (PMT) over 5 years. METHODS: The sample comprised 212 individuals diagnosed with chronic moderate-severe periodontitis, who had finished active periodontal treatment, were incorporated in a PMT program. Individuals were divided in to two groups: 96 regular compliers (RC) and 116 irregular compliers (IC). Full-mouth periodontal examination was performed. Social, demographic, behavioral and biological variables of interest were collected at all PMT visits. The effect of risk predictors and confounders for TL, as well as the underlying reasons of TL, were assessed by univariate and multivariate analysis. RESULTS: TL was significantly lower among RC (0.12 teeth lost/year) in comparison to IC (0.36 teeth lost/year; p < 0.01). Individuals that were > 55 years old, males and smokers lost significantly more teeth in both groups (with IC > RC). The number of teeth lost due to periodontal reasons was significantly higher than TL for other reasons in both groups (p < 0.01). The final linear and logistic model for TL included: male gender, smoking, probing depth 4-6 mm in up to 10% of sites and irregular compliance. CONCLUSION: IC individuals undergoing PMT presented higher rates of TL when compared to RC individuals. Findings demonstrated the influence of irregular compliance and the importance of monitoring other risk predictors for TL such as smoking, male gender and severity of probing depth during PMT.

Fracture susceptibility of endodontically treated teeth.

AIM: To assess the influence of cervical preparation on fracture susceptibility of roots. MATERIAL AND METHODS: During root canal instrumentation, the cervical portions were prepared with different taper instruments: I: no cervical preparation; II: #30/.08; III: #30/.10; IV: #70/.12. The specimens were sealed with the following filling materials (n = 8), A: unfilled; B: Endofill/gutta-percha; C: AH Plus/gutta-percha; D: Epiphany SE/Resilon. For the fracture resistance test, a universal testing machine was used at 1 mm per minute. RESULTS: anova demonstrated difference (P < 0.05) between taper instruments with a higher value for group I (205.3 ± 77.5 N) followed by II (185.2 ± 70.8 N), III (164.8 ± 48.9 N), and IV (156.7 ± 41.4 N). There was no difference (P > 0.05) between filling materials A (189.1 ± 66.3 N), B (186.3 ± 61.0 N), C (159.7 ± 69.9 N), and D (176.9 ± 55.2 N). CONCLUSIONS: Greater cervical wear using a #70/.12 file increased the root fracture susceptibility, and the tested filling materials were not able to restore resistance.

Effect of gamma irradiation and restorative material on the biomechanical behaviour of root filled premolars.

AIM: To investigate ex vivo the influence of gamma irradiation therapy and restorative material on fracture resistance, fracture mode and strain of root filled human premolars. METHODOLOGY: Sixty extracted human maxillary premolar teeth were randomly divided into six groups (n = 10) determined by two study factors: (i) restorative materials: sound teeth, root filled teeth restored with composite resin, root filled teeth restored with amalgam; (ii) gamma irradiation: irradiated (subjected to 60 Gy of gamma irradiation in daily increments of 2 Gy) and nonirradiated. For the strain gauge test, two strain gauges per sample were attached on the buccal and palatal cusp surfaces (n = 5). Strain values were recorded during loading of 0-150 N. Fracture resistance (N) was assessed in a mechanical testing machine (n = 10). Strain gauge for each cusp and fracture resistance data were analysed by two-way anova (3 × 2) followed by the Tukey's honestly significant difference test (α = 0.05). The failure mode was evaluated using an optical stereomicroscope and classified according to the location of the failure. RESULTS: Gamma radiation therapy significantly reduced the fracture resistance of intact teeth. The strain was higher for teeth restored with amalgam than for those restored with composite resin. The teeth restored with composite resin had similar strain values to sound teeth. Nonirradiated teeth had more restorable failures than irradiated teeth. CONCLUSIONS: Gamma irradiation significantly reduced fracture resistance and increased cusp strain. The use of composite resin resulted in better biomechanical behaviour than amalgam for restoring root filled teeth whether or not they were submitted to radiotherapy.

Microhardness of intracoronal dentin exposed to bleaching and fluoride treatment.

OBJECTIVES: The aim of this study was to assess the surface microhardness (SMH) of intracoronal dentin exposed to 38% hydrogen peroxide (HP) light-activated or not and to 2% sodium fluoride gel (F2%) or 5% varnish (F5%). STUDY DESIGN: Intracoronal dentin specimens were exposed to bleaching (B), bleaching and light activation (BL), or no bleaching (NB), followed by F2%, F5%, or no exposure (NF). SMH test was performed. Four specimens of each group were analyzed by scanning electron microscopy (SEM). RESULTS: Analysis of variance and Tukey test (α = 5%) showed higher SMH of NB than BL or B. Specimens exposed to F5% presented the highest SMH and differed from F2% and NF. BL + NF yielded inferior SMH and was similar to B + NF, BL + F2%, B + F2%, BL + F5%, and NB + NF. NB + F5% showed superior values and did not differ from NB + F2%, B + F5%, and NB + NF. CONCLUSIONS: Bleaching with 38% HP, light-activated or not, reduced the SMH of intracoronal dentin. F5% provided SMH to the level of unbleached specimens.

Tratamento endodôntico de incisivo lateral superior após falha da cirurgia parendodôntica / Endodontic treatment of maxillary lateral incisor after failed surgery paraendodontic

O propósito deste artigo é relatar um caso clínico no qual foi realizada uma intervenção cirúrgica parendodôntica no incisivo lateral superior esquerdo em um paciente para remoção de uma lesão no periodonto apical, sem um prévio tratamento endodôntico, tendo a incisão, a enucleação da lesão e a sutura sido feitas de maneira equivocada, provocando uma fenestração tecidual no tecido gengival, expondo o tecido ósseo ao meio bucal, com consequente infecção e grande quantidade de exsudato purulento. Foi realizado um tratamento endodôntico no dente em questão, utilizando-se a limpeza e modelagem do canal com instrumentação rotatória e hipoclorito de sódio a 5,25%, cavitação ultrassônica com EDTA a 17%, curativo intracanal com hidróxido de cálcio e, em uma sessão posterior,obturação com guta-percha termoplastificada e cimento resinoso. Durante o exame clínico radiográfico de proservação realizado após quatro meses de concluído o tratamento endodôntico, foi observado a recuperação do tecido gengival e a radiografia periapical mostrou uma regeneração do tecido ósseo, onde antes existia a lesão.

The intention of this article is to tell a clinical case in which was made a endodontic surgery in a patient to remove a lesion in the apical periodonto and was carried throughan endodontic surgical intervention in the maxillary lateral incisor without a previous endodontic treatment, having the incision, the enucleation of the injury and the been suture made in a mistake way, provoking a tecidual fenestration in the gum of the patient,displaying the osseous tissue to the buccal way, with consequent infection and greatamount of purulent exudates. An endodontic treatment in the tooth in question was carried through, using itself cleaning and shaping of the canal with rotatory instrumentation and 5,25% sodium hypochlorite, ultrasonic cavitation with 17% EDTA, dressing intra canalwith of calcium hydroxide and, in a posterior session, obturation with termoplastificad gutta-percha and resinous sealer. During the clinical examination of flare-up conducted after four months of carried through the endodontic treatment was observed a recovery of the gum tissue and the periapical x-ray showed a regeneration of the osseous tissue,where before the injury existed.

Avaliação clínica de duas técnicas de clareamento de dentes desvitalizados / Clinical evaluation of two bleaching techniques for nonvital teeth

Foi avaliada, clinicamente. a eficácia de duas técnicas de clareamento de dentes desvitalizados empregando peróxido de carbamida a 37% (técnica mediata) e 16% (técnica supervisionada) comparando-as à técnica mediada que emprega perborato de sódio e água destilada corno agente clareador. Uma amostra de conveniência composta por 30 pacientes de ambos os gêneros: idade acima de 21 anos; que apresentavam um ou mais dentes anteriores (superiores e/ou inferiores) tratados endodonticamente e escure- cidos, foi distribuída aleatoriamente em 3 grupos, de acordo com O material e a técnica de clareamento a ser utilizada. Os resultados evidenciaram que a causa mais frequente para o escurecimento dos dentes foi a decomposição do tecido pulpar(60%dos casos); a principal razão do tratamento endodôntico foi a necrose bacteriana (93% dos casos) e que a técnica supervisionada apresentou melhores resultados que a técnica de clareamento interno com peróxido de carbarmida 37%. Entretanto, quando comparados ao perborato de sódio +água destilada, não mostraram relações estatisticamente significantes quanto ao nível de clareamento alcançado. Assim, o estudo concluiu que as técnicas de clareamento de dentes desvitalizados empregadas, quando utilizadas de maneira adequada, apresentam resultados satisfatórios. A técnica supervisionada com Peróxido de carbamida a 16% representa lima alternativa viável para o tratamento de dentes escurecidos e tratados endodonticamente.

lntroduction -Efficacy of two vital teeth bleaching techniques were clinically evaluated using 37% carbamide peroxide (mediate technique) and 16% carbamide peroxide (supervised technique) comparing them with the mediate technique that uses sodium perbotate and distillated water as bleaching agent. Materials and Methods - Sample composed by 30 patients both gender; more than 21 years old that presents one or more anterior teeth (upper and/or lower) darkened and endodontically treated was randomized distributed in 3 groups according to lhe material and bleaching technique used. Results - After results analyze, it was observed that the most frequent cause of tooth stain was pulp tissue decomposition (60% of all cases): the main reason for endodontic treatment was bacterial necrosis (93% of all cases) and supervised technique showed better than mediate technique with 37% carbamide peroxide. However, both of them when compared with soditum perborate and distillated water technique didn 't show significant statistically retalion about bleaching achieved results. Conclusions - So, the stuy concluded that both no vital teeth bleaching techniques presented good results, when suitable used. Supervised technique using 16% carbamide peroxide represents aviable treatment alternative for darkened endodontic treated teeth.

Prevalence of apical periodontitis in root canal-treated teeth from an urban French population: influence of the quality of root canal fillings and coronal restorations.

This cross-sectional study determined the prevalence of apical periodontitis in 1035 root canal-treated teeth from adult French patients and investigated the influence of the quality of canal fillings and coronal restorations on the periradicular status. Periapical radiographs were used for analyses, and teeth were classified as healthy or diseased according to the periapical index scoring system. Overall, the prevalence of apical periodontitis in root canal-treated teeth was 33%. Only 19% of the teeth had endodontic treatments rated as adequate. The success rate (number of healthy teeth) for cases with adequate endodontic treatment was 91%, which was significantly higher when compared with teeth with inadequate treatment (61%). Teeth with adequate restorations had significantly decreased prevalence of apical periodontitis (29%) as compared with teeth with inadequate restorations (41%). The combination of adequate endodontic treatment and adequate restorations yielded the highest success rate (93.5%). The quality of the endodontic treatment was the most important factor for success, although the quality of the coronal restoration also influenced the treatment outcome.

Orthodontic root resorption of endodontically treated teeth.

The purpose of this study was to evaluate, radiographically, whether there is similarity in the apical root resorption found in endodontically treated teeth and untreated teeth when they are submitted to orthodontic treatment. From 2,500 treatment records examined, 16 patients were selected who had a maxillary central incisor treated endodontically before initiation of the orthodontic movement, and a vital homologous tooth (for control). Measurements were made by comparing the periapical radiographs taken before and after the orthodontic treatment. There was no statistically significant difference (p>0.05) in apical root resorption found in the endodontically treated teeth compared to the group of vital teeth.

Fracture strength of endodontically treated teeth with flared root canals and restored with different post systems.

BACKGROUND: Many post systems are available to clinicians, yet no consensus exists about which one is better in restoring endodontically treated teeth. PURPOSE: This study evaluated the fracture strength of teeth with flared canals and restored with two fiber-reinforced resin systems (glass fiber: FRC Postec [Ivoclar Vivadent, Schaan, Liechtenstein]; quartz fiber: D.T. Light-Post [Bisco Dental Products, Schaumburg, IL, USA]), and one custom cast base metal (Ni-Cr) post and core system. METHODS: Thirty anterior teeth had their crowns removed below the cemento-enamel junction and were endodontically treated. The canals were prepared for post fixation, and the canal walls were flared using a taper diamond bur. The prepared roots were randomly divided into three groups according to the post system. All posts were cemented with an adhesive resin cement. For the fiber-reinforced resin posts, cores were built up using microhybrid composite. Metallic crowns were luted using zinc phosphate cement. Specimens were loaded at 45 degrees in a universal testing machine at a crosshead speed of 0.5 mm/min until failure. The mode of failure was classified as repairable or nonrepairable. RESULTS: Teeth restored with cast posts had fracture strength twice that of teeth restored with resin posts. Fiber-reinforced resin posts failed at a compressive force comparable to clinical conditions, but all failures were repairable. CONCLUSION: Fracture strength and mode of failure in anterior teeth with flared canals varied according to the type of post used to support a crown. CLINICAL SIGNIFICANCE: Under the conditions of this study, cast posts are preferable to restore endodontically treated teeth with flared canals and no ferrule.

Tratamiento de dientes con fractura vertical: una alternativa en la terapéutica clínica / Treatment of teeth with vertical fracture: an alternative in clinical therapeutics

En general, el pronóstico de las piezas dentarias con tratamiento endodóntico afectadas de fracturas longitudinales es desfavorable. No obstante, optamos por la alternativa de intentar conservarlas aplicando una metodología acorde al caso clínico. Se trataron once piezas dentarias que presentaban las características citadas divididas en tres grupos para su tratamiento: grupo 1 (n=2) fracturas radiculares, portadoras de pernos, tratadas mediante el uso de ionómero de vidrio y posterior colocación de perno. Grupo 2 (n=1) fracturas corono-radicular fijada sólo con el ionómero vítreo. Grupo 3 (n=8) fracturas corono-radiculares que recibieron tratamiento con ionómero de vidrio asociado con ligadura de alambre y corona estampada. Se efectuó el seguimiento a distancia mediante controles clínicos radiográficos trimestrales durante un período de tres años, y se concluyó que la temprana detección de la fractura, la consolidación con ionómero vítreo y la adecuada fijación de sus cabos con ligaduras de alambre y coronas metálicas parecen ser indispensables para, en algunos casos, lograr el éxito final (AU)

Fracture resistance of endodontically treated roots after restoration.

This study evaluated the shear strength resistance of endodontically treated roots that were restored by two different techniques. Twenty-seven recently extracted single-rooted teeth with similar anatomic characteristics were sectioned to obtain the same length for all specimens. Group I (GI) consisted of 14 roots restored with cast post-core (nickel-chromium alloy) and cemented using zinc phosphate cement; group II (GII) consisted of 13 roots restored with steel prefabricated posts (FKG) cemented with zinc phosphate cement and rotated with caution for anchorage. The crown portion of this group was made using a hybrid composite resin (Prisma APH). Results showed that on all specimens of GI the fracture occurred in the cervical root structure while in GII the composite resin fractured in all specimens. Statistical analysis showed a significantly higher resistance to fracture for GI than GII. The specimens were sectioned longitudinally for stereoscopic microscope analysis (63x) and did not show fracture lines in the dentin anchorage post area for any of the specimens.

Tratamento cirúrgico de uma perfuraçäo à nível de terço médio da raiz de um dente portador de uma prótese com núcleo / Surgical treatment for perforation in the middle third part of the root of a tooth with prosthesis and post

Os autores apresentam um caso de perfuraçäo, com núcleo ultrapassado na altura do terço médio da raiz, do primeiro pré-molar inferior esquerdo, além da presença de parte de outro núcleo abaixo do anterior, com fistula na face vestibular do rebordo alveolar. Constatou-se, radiograficamente, extensa lesäo circunscrita no periodonto adjacente à área da perfuraçäo. A tentativa da remoçäo do núcleo inevitavelmente levaria à fratura da raiz e o retratamento endodôntico era dispensável porque o tratamento anterior foi considerado adequado e a regiäo periapical estava íntegra. Assim optou-se pela intervençäo cirúrgica e selamento da área da perfuraçäo com amálgama. Foi realizado aplainamento da superfície radicular, através da eliminaçäo do excesso do núcleo ultrapassado para o periodonto, corrigida a perfuraçäo da raiz com amálgama e curetado o tecido de granulaçäo presente na lesäo. A cavidade óssea foi preenchida com enxerto ósseo bovino e recoberta com uma barreira de colágeno bovino. Constatou-se o progressivo desaparecimento da lesäo após acompanhamento clínico e radiográfico de 7 dias até 20 meses, embora näo tenha havido reinserçäo da junçäo epitelial ao material do selamento

Reabsorçäo cervical externa, após clareamento em dentes tratados endodonticamente / External cervical resorption, after the bleaching of endodontically treatment teeth

Este trabalho é uma revisäo de literatura, onde trata-se de um dos problemas de maior complexidade para o Cirurgiäo Dentista, que é o diagnóstico e tratamento da reabsorçäo radicular. As reabsorçöes dentárias podem ser decorrentes de clareamento de dentes tratados endodonticamente e entre estas a reabsorçäo externa, ocorre com freqüência no terço cervical da raiz, na área de aderência gengival, ao nível da crista óssea alveolar. Embora muitas hipóteses tenham sido sugeridas, o agente causador näo foi convencidamente estabelecido. Os primeiros a associarem reabsorçäo com clareamento foram Harrington e Natkin (1979). Estes casos envolviam necrose pulpar decorrente de trauma em dente permanente jovem, onde realizou-se endodontia e posteriormente clareamento. Os autores achavam que a reabsorçäo ocorria depois que o agente clareador passava através dos túbulos dentinários, chegando ao ligamento periodontal. Mais recentemente, Fuss e cols. (1989), por meio de um estudo ®in vitro¼, que os agentes clareadores podem se infiltrar para os tecidos periodontais, constituindo-se em agentes etiológicos da reabsorçäo externa. A literatura está repleta de estudos e pesquisas neste sentido, porém as controvérsias existem até com relaçäo a procedimentos bem sucedidos. Deste modo o profissional se defronta, freqüentemente, com dúvidas na escolha da melhor forma de tratamento