The ins and outs of root resorption.

Root resorption is a poorly understood phenomenon and is often misdiagnosed and, as a result, inappropriately treated. The aim of this paper is to provide a practical guide for diagnosis of root resorption lesions using a simple classification, and to describe the principles of management of these resorptive defects in everyday practice.

Manejo quirúrgico-endodóncico de una reabsorción cervical invasiva clase III empleando composite / Endo-surgical management of a class III invasive cervical resorption using composite

La reabsorción cervical invasiva (RCI) es un tipo de reabsorción radicular insidiosa y agresiva que se origina en la superficie radicular externa. Típicamente, suele pasar inadvertida puesto que en la mayoría de los casos es asintomática. El uso de la tomografía computarizada con haz cónico (CBCT) mejora el diagnóstico y la planificación y la utilización dental mejora la realización del tratamiento. El objetivo principal de un tratamiento óptimo de ICR es la eliminación e inactivación del proceso de reabsorción y la reconstrucción del defecto. Entre los materiales empleados en la literatura para el sellado del defecto, el composite parece ser una opción válida. En el presente caso clínico se describe el tratamiento combinado quirúrgico-endodóncico de una reabsorción cervical invasiva clase III de Heithersay sellada con composite. Después de un año de seguimiento, el paciente se mostraba asintomático y la rarefacción ósea peri radicular ha disminuido significativamente no existiendo recidiva de la reabsorción

Invasive cervical resorption (ICR) is an aggressive type of radicular resorption that originates in the external radicular surface. It can typically go unnoticed since it is often asymptomatic. The use of cone beam computed tomography (CBCT) increases in a greater diagnostic and planning and a dental microscope increases the proper execution of the treatment. The main objective of an optimal treatment of ICR is the elimination and inactivation of the resorptive process, and the reconstruction of the defect. Among the dental material used in the literature for sealing the defect, composite seems to be a valid option. The present case-report describes a combined surgical and endodontic treatment of a Heithersay class III invasive cervical resorption sealed with dental composite. A one-year follow-up shows the patient to be asymptomatic, and the bone rarefaction to have decreased significantly, with no evidence of a resorption recurrence

External cervical resorption: a three-dimensional classification.

This article describes a novel three-dimensional classification for external cervical resorption (ECR). The European Society of Endodontology and American Association of Endodontists & American Academy of Oral & Maxillofacial Radiology position statements advise that Cone beam computed tomography should be considered for the assessment and/or management of root resorption if it appears to be clinically amenable to treatment following clinical and conventional radiographic examination. The new classification takes into account the ECR lesion height (1: at CEJ level or coronal to the bone crest (supracrestal), 2: extends into the coronal third of the root and apical to the bone crest (subcrestal), 3: extends into the mid-third of the root, 4: extends into the apical third of the root), circumferential spread (A: ≤90° B: ≤180° C: ≤270° D: >270°) and proximity to the root canal (d: lesion confined to dentine, p: probable pulpal involvement), thus classifying ECR in three dimensions. At present, there is no classification to accurately describe ECR. This novel and clinically relevant three-dimensional classification should allow effective and accurate communication of ECR lesions between colleagues. It will also allow the effect of the nature of ECR on the outcome of treatment to be assessed objectively.

Impact of Cone-beam Computed Tomography on Treatment Planning for External Cervical Resorption and a Novel Axial Slice-based Classification System.

INTRODUCTION: The aim of this study was to compare treatment plans for external cervical resorption (ECR) developed from periapical (PA) radiographs and cone-beam computed tomographic (CBCT) imaging. The secondary aim of this study was to test a new classification system for ECR based on CBCT axial slice analysis. METHODS: ECR was identified in 56 teeth (47 patients) from a database of 928 CBCT images. Strict exclusion criteria resulted in a sample of 30 ECR teeth (25 patients) and 10 ECR-free control teeth. Six examiners evaluated CBCT and matched PA images in separate sessions. Examiners classified ECR according to the Heithersay classification system and the novel Rohde classification system and provided a treatment plan. RESULTS: All 30 ECR cases were identified by CBCT imaging and 29 by PA radiography. Interrater agreement was uniformly higher with CBCT imaging, and treatment plans developed from CBCT scans differed from those developed with PA radiographs in 56.7% of the cases. Examiners recommended ECR repair in the majority of cases (59.8% of CBCT images and 56.7% of PA radiographs). The Heithersay classification was dependent on the method of imaging with a greater prevalence of class 4 reported with CBCT imaging (P = .0016). The Rohde classification system significantly predicted the recommended treatment plan (P = .002 for Rohde class 2 and P = .043 for Rohde class 3). All Heithersay classifications failed to statistically predict treatment plans. CONCLUSIONS: Treatment plans changed between PA and CBCT imaging in the majority of cases evaluated. If CBCT imaging is available, the Rohde classification system may help guide treatment planning for cases of ECR.

A comparative study of cone beam computed tomography and conventional radiography in diagnosing the extent of root resorptions.

BACKGROUND: Root resorptions are assessed and diagnosed using different radiographical techniques. A comparison of the ability to assess resorptions on two-dimensional (2D) and three-dimensional (3D) radiographs is, hitherto, lacking. The aims of this study were to evaluate the accuracy of 2D (periapical radiographs, PA and panoramic radiograph, PAN) and 3D (cone beam computed tomography, CBCT) radiographic techniques in measuring slanted root resorptions compared to the true resorptions, a histological gold standard, in addition to a comparison of all the radiographic techniques to each other. METHODS: Radiographs (CBCT, PA, and PAN), in addition to histological sections, of extracted deciduous canines from thirty-four patients were analyzed. Linear measurements of the most and least resorbed side of the root, i.e., "slanted" resorptions, were measured using an analyzing software (Facad ®). For classification of slanted root resorptions, a modified Malmgren index was used. RESULTS: PAN underestimated the root length on both the least and most resorbed side. Small resorptions, i.e., low modified Malmgren scores, were more difficult to record and were only assessed accurately using CBCT. The root resorption scores were underestimated using PA and PAN. In assessment of linear measures, PAN differed significantly from both CBCT and PA. CONCLUSIONS: CBCT is the most accurate technique when measuring and scoring slanted root resorptions.

Atypical root resorption following root fractures in primary teeth.

Atypical root resorption (ARR) is the condition of a superficial and circumferential resorption process along the lateral and/or apical root surface of a primary maxillary incisor. This case series demonstrates longitudinal observations of six patients with atypical root resorption following root-fractured primary incisors. The characteristics of atypical root resorption were different from pathologic root resorption.

Reabsorção dentária externa: não se faz o canal para tratá-la! / External root resorption: root canal treatment is not recommended

O presente artigo visa fundamentar as razões pelas quais, em casos de dentes com reabsorção dentária externa, não se deve fazer o canal para tratá-la. Isso se faz apenas nos dentes com contaminação ou necrose pulpar, para remover a inflamação periapical induzida pelos produtos microbianos. Frente a casos de reabsorção dentária externa, as condutas devem priorizar sempre a seguinte sequência: primeiro, identificar precisamente a causa; depois, planejar a forma de abordagem terapêutica e, por fim, adotar as condutas de forma muito bem fundamentada. Não se consegue controlar o processo reabsortivo que está ocorrendo na parte externa por via pulpar; afinal, as causas estão atuando no ligamento periodontal. Não se tem qualquer evidência que justifique fazer o tratamento endodôntico, via canal, para controlar processos reabsortivos externos quando a polpa está com vitalidade.

Location and severity of root resorption related to impacted maxillary canines: a cone beam computed tomography (CBCT) evaluation.

BACKGROUND: The present investigation was designed to determine the location and severity of root resorption associated with impacted maxillary canine teeth using cone beam computed tomography (CBCT). A secondary aim was to identify possible influencing factors. METHODS: The radiological reports of 183 patients, radiographed with a small-volume CBCT focussed on the impacted maxillary canine teeth, were assessed. Eighty-five patients had resorption associated with the impaction. The CBCT image datasets were viewed to determine the location and severity of the lesions. RESULTS: A total of 110 impacted maxillary canine teeth resorbed 120 adjacent teeth, including 14 premolars and one permanen molar. The apical third and palatal surface were commonly involved. Fifty per cent of the resorptive lesions were mild, 20% moderate and 30% severe. There was no significant relation between age or gender on the number, location or severity of resorption. There was a statistically significant correlation between the number of impacted canine teeth an'd the number of teeth resorbed, as well as the tooth type and the surface involved in the resorption. CONCLUSIONS: All root levels and surfaces of teeth associated with impacted maxillary canine teeth can be resorbed to different levels of severity. Neither age nor gender influences the number, location or severity of the resorption.

Outcome assessment of lingual and labial appliances compared with cephalometric analysis, peer assessment rating, and objective grading system in Angle Class II extraction cases.

OBJECTIVE: To validate our hypothesis that there would be significant differences in treatment outcomes, including cephalometric values, degree of root resorption, occlusal indices, and functional aspect, between cases treated with labial and lingual appliances. MATERIALS AND METHODS: Twenty-four consecutively treated Class II cases with extractions and lingual appliance were compared with 25 matched cases treated with extraction and labial appliance. Orthodontic treatment outcomes were evaluated by cephalometric analysis, peer assessment rating, and an objective grading system (OGS). Additionally, functional analysis was also performed in both groups after orthodontic treatment. Statistical comparison was performed using the Wilcoxon signed rank test within the groups, and the Mann-Whitney U-test was used to compare between the labial and lingual groups. RESULTS: The only significant difference between the groups was that the interincisal angle was larger in the lingual group than in the labial group. OGS evaluation showed that control over root angulation was significantly worse in the lingual group than in the labial group. There was no significant difference between groups in the amount of root resorption or in functional evaluation. CONCLUSIONS: Generally, lingual appliances offer comparable treatment results to those obtained with labial appliances. However, care should be taken with lingual appliances because they are more prone to produce uprighted incisors and root angulation.

A retrospective radiographic study on the effect of natural tooth-implant proximity and an introduction to the concept of a bone-loading platform switch.

PURPOSE: The aim of this study was to evaluate the effect of tooth-implant proximity using an implant system with a double platform shift that was designed to load bone coronal to the implant-abutment cohort study was conducted between January 2008 and December 2009. The sample was composed of patients who had received at least one 5-mm-wide hydroxyapatite-coated single-tooth Bicon implant that had been placed adjacent to at least one natural tooth. Descriptive statistics and univariate and multivariate linear mixed-effects regression models, adjusted for multiple implants in the same patient, were utilized. The primary predictor variable was the horizontal distance between implant and adjacent tooth, and the primary outcome variable was the change in peri-implant bone levels over time. RESULTS: Two hundred six subjects who received 235 plateau root-form implants were followed for an average of 42 months. Tooth-implant distance ranged between 0 and 14.6 mm. Out of 235 implants, 43 implants were placed < 1 mm to an adjacent natural tooth on mesial and/or distal sides. The proximity of a plateau root-form implant was not associated with complications on the adjacent tooth such as bone loss, root resorption, endodontic treatment, pain, or extraction. The proximity of an adjacent tooth was not a risk factor for the failure of a plateau root-form implant. After adjusting for other covariates in a multivariate model, the proximity of a natural tooth did not have a statistically significant effect on peri-implant bone levels (P = .13). The extraction of an adjacent tooth was associated with a significant increase in peri-implant bone loss (P = .008). CONCLUSION: The placement of a plateau root-form implant with a sloping shoulder in close proximity to an adjacent tooth did not cause damage to that tooth or lead to bone loss or the failure of the implant.

Effect of frequent application of low-level laser therapy on corticotomized tooth movement in dogs: a pilot study.

PURPOSE: The purposes of the present study were to evaluate the effects of frequent applications of low-level laser therapy (LLLT) on corticotomy-assisted tooth movement in a beagle dog model and to compare the effects in the mandible and maxilla. MATERIALS AND METHODS: In 4 male beagles, the maxillary and mandibular second premolars were extracted. The third premolars were corticotomized and then protracted from the canines with a continuous force of 200 g. Daily LLLT (using an aluminum gallium indium phosphide [AlGaInP] diode) was applied at the buccal mucosa of the corticotomized premolars on 1 side only. The tooth movement was measured for 8 weeks. Fluorochromes were injected intravenously at the start of the experiment (T0) and after 2 (T2), 4 (T4), and 8 (T8) weeks to evaluate new bone formation on the tension sides. Histomorphometric and immunohistologic evaluations were performed. RESULTS: In the mandible, the movement of the corticotomized premolars in the LLLT plus corticotomy group was less than that in the corticotomy-only group, although the difference was not statistically significant. In the maxilla, no significant differences between the 2 groups were found. Osteoclastic and proliferating cell activities and the amount of new bone formation were greater in the mandibular LLLT plus corticotomy group than in the corticotomy-only group. CONCLUSIONS: The frequent application of LLLT showed no significant effect on the corticotomized tooth movement.

Age and timing of pulp extirpation as major factors associated with inflammatory root resorption in replanted permanent teeth.

INTRODUCTION: External root resorption (ERR) is a serious complication after replantation, and its progressive inflammatory and replacement forms are significant causes of tooth loss. This retrospective study aimed to evaluate the factors related to the occurrence of inflammatory ERR (IERR) and replacement ERR (RERR) shortly after permanent tooth replantation in patients treated at the Dental Trauma Clinic at the School of Dentistry, Federal University of Minas Gerais, Belo Horizonte, Brazil. METHODS: Case records and radiographs of 165 patients were evaluated for the presence, type, and extension of ERR and its association with age and factors related to the management and acute treatment of the avulsed tooth by using the logistic regression model. RESULTS: The patient's age at the moment of trauma had a marked effect on the ERR prevalence and extension. The patients older than 16 years at the moment of trauma had less chance of developing IERR and RERR (77% and 87%, respectively) before the pulp extirpation, regardless of the extension of the resorption. The patients older than 11 years of age at the moment of trauma showed the lowest indices of IERR (P = .02). Each day that elapsed between the replantation and the pulp extirpation increased the risk of developing IERR and RERR by 1.2% and 1.1%, respectively, and also raised the risk of severe IERR by 0.5% per day. CONCLUSIONS: The risk of mature teeth developing severe IERR before the onset of endodontic therapy was directly affected by the timing of the pulpectomy and was inversely proportional to age. Systemic antibiotic therapy use had no effect on the occurrence and severity of IERR in mature teeth. The occurrence of RERR before the onset of endodontic treatment stimulates further investigations of the early human host response to trauma and subsequent infection.

Localization of impacted maxillary canines and root resorption of neighbouring teeth: a study assessing the diagnostic value of panoramic radiographs in two groups of observers.

OBJECTIVES: To assess the diagnostic value of panoramic views (2D) of patients with impacted maxillary canines by a group of trained orthodontists and oral surgeons, and to quantify the subjective need and reasons for further three-dimensional (3D) imaging. MATERIALS AND METHODS: The study comprises 60 patients with panoramic radiographs (2D) and cone beam computed tomography (CBCT) scans (3D), and a total of 72 impacted canines. Data from a standardized questionnaire were compared within (intragroup) and between (intergroup) a group of orthodontists and oral surgeons to assess possible correlations and differences. Furthermore, the questionnaire data were compared with the findings from the CBCT scans to estimate the correlation within and between the two specialties. Finally, the need and reasons for further 3D imaging was analysed for both groups. RESULTS: When comparing questionnaire data with the analysis of the respective CBCT scans, orthodontists showed probability (Pr) values ranging from 0.443 to 0.943. Oral surgeons exhibited Pr values from 0.191 to 0.946. Statistically significant differences were found for the labiopalatal location of the impacted maxillary canine (P = 0.04), indicating a higher correlation in the orthodontist group. The most frequent reason mentioned for the further need of 3D analysis was the labiopalatal location of the impacted canines. Oral surgeons were more in favour of performing further 3D imaging (P = 0.04). CONCLUSIONS: Orthodontists were more likely to diagnose the exact labiopalatal position of impacted maxillary canines when using panoramic views only. Generally, oral surgeons more often indicated the need for further 3D imaging.

The four mechanisms of dental resorption initiation.

The aim of this study is to present a classification with a clinical application for root resorption, so that diagnosis will be more objective and immediately linked to the source of the problem, leading the clinician to automatically develop the likely treatment plan with a precise prognosis. With this purpose, we suggest putting together all diagnosed dental resorptions into one of these four criteria: 1) Root resorption caused by cementoblast cell death, with preservation of the Malassez epithelial rests. 2) Root resorption by cementoblasts and Malassez epithelial rests death. 3) Dental resorption by odontoblasts cell death with preservation of pulp vitality. 4) Dental resorption by direct exposure of dentin to gingival connective tissue at the cementoenamel junction gaps.

The four mechanisms of dental resorption initiation

The aim of this study is to present a classification with a clinical application for root resorption, so that diagnosis will be more objective and immediately linked to the source of the problem, leading the clinician to automatically develop the likely treatment plan with a precise prognosis. With this purpose, we suggest putting together all diagnosed dental resorptions into one of these four criteria: 1) Root resorption caused by cementoblast cell death, with preservation of the Malassez epithelial rests. 2) Root resorption by cementoblasts and Malassez epithelial rests death. 3) Dental resorption by odontoblasts cell death with preservation of pulp vitality. 4) Dental resorption by direct exposure of dentin to gingival connective tissue at the cementoenamel junction gaps.

O presente trabalho propõe-se a apresentar uma classificação, com aplicação clínica, para as reabsorções dentárias, para que o diagnóstico seja objetivo e imediatamente ligado à causa do problema, levando automaticamente o clínico ao provável plano de tratamento e a um prognóstico preciso. Com esse objetivo, sugerimos agrupar cada caso clínico de reabsorção dentária em um dos seguintes grupos: 1) Reabsorções radiculares pela morte dos cementoblastos, com manutenção dos restos epiteliais de Malassez. 2) Reabsorções radiculares pela morte dos cementoblastos e dos restos epiteliais de Malassez. 3) Reabsorções dentárias pela morte dos odontoblastos, com manutenção da vitalidade pulpar. 4) Reabsorções dentárias pela exposição direta da dentina ao tecido conjuntivo gengival, nos gaps da junção amelocementária.

Resorption: part 1. Pathology, classification and aetiology.

This paper will explore the pathological process involved in dental resorption as well as its classifications and aetiology. The second subsequent paper will look at its diagnosis and management.

Validation of the cone beam computed tomography-based stereolithographic surgical guide aiding autotransplantation of teeth: clinical case-control study.

OBJECTIVE: To compare the outcome of cone beam computed tomography (CBCT)-based surgical planning and transfer technique for tooth autotransplantation versus conventional autotransplantation. STUDY DESIGN: The study material comprised 40 pediatric subjects in whom 48 teeth were transplanted following a case-control design. While the study group (mean age 11 years) underwent CBCT imaging for surgical planning and transfer via stereolithographic tooth replica fabrication, the historical control group (mean age 12 years) was subjected to conventional autotransplantation. RESULTS: The CBCT-based preoperative planning and the use of a tooth replica decreased the extra-alveolar time and reduced the number of positioning trials with the donor tooth. In the control group, 6 patients showed 1 or more complications, while this was noticed for only 2 study patients. CONCLUSION: CBCT-based surgical planning of tooth autotransplantation may benefit from a shorter surgical time, while being a less invasive technique, causing fewer failures than a conventional approach.

Apical resorption in teeth with periapical lesions: correlation between radiographic diagnosis and SEM examination.

This study correlated the radiographic findings and scanning electron microscopy (SEM) images of external apical resorption (EAR) in teeth with periapical lesions. Standard radiographs were taken from 45 teeth with periapical lesions before their extraction. Using a radiographic examination, the root apex of each tooth was classified according to the EAR into the following categories: radiographic external apical resorption (REAR) absent, superficial and deep. The apical root surface was also examined with SEM. Photomicrographs of EARs were classified as periforaminal (PEAR) and foraminal (FEAR) in three degrees: 0, 1 and 2. REAR was present in 72.5% of cases, of which 20% were deep. Based upon SEM analysis, PEAR and FEAR occurred in 75.6% and 66.7% of cases respectively; 51.2% and 59% respectively, of these teeth received a score of 2. Only 15.4% of the specimens were unaffected by EAR. When teeth with periapical lesions were examined for EAR with both radiography and by SEM, there was no correlation between the findings.

Uso de trióxido mineral agregado (MTA) en el tratamiento de una reabsorción cemento-dentinaria externa: caso clínico / The use of mineral trioxide aggregate (MTA) in external root resorption treatment: a clinical case

Objetivos: se describe el tratamiento de una pieza dentaria que presenta reabsorción cemento-dentinaria externa (RCDE) como consecuencia de un traumatismo ocurrido hace veinticinco años. Caso clínico: la resolución se completó en dos etapas. En la primera, dado que se observó una obturación incorrecta, se realizó el retratamiento endodóntico y se obturó con conos de gutapercha y sellador Sealer 26. En la sesión siguiente, se levantó un colgajo con el objetivo de exponer y explorar la zona radiolúcida presente en distal de la raíz a la altura del tercio medio. Se realizó un curetaje y se rellenó la cavidad de la reabsorción con trióxido mineral blanco (MTA). La rehabilitación estética de la corona fue realizada con una carilla de composite a mano alzada. Después de dos años de haber realizado el tratamiento y en controles radiográficos periódicos, se observó que la RCDE se detuvo. Conclusión: las reabsorciones cemento-dentinarias externas inflamatorias son lesiones relativamente frecuentes luego de un traumatismo dentario. Es importante realizar un diagnóstico temprano para evitar su evolución y la consecuente pérdida de la pieza. El material fue elegido teniendo en cuenta sus propiedades físicas y químicas, entre las que se destacan su baja citotoxicidad, la capacidad de solidificar en presencia de humedad y el estímulo que ejerce sobre la regeneración del ligamento periodontal.(AU)

Uso de trióxido mineral agregado (MTA) en el tratamiento de una reabsorción cemento-dentinaria externa: caso clínico / The use of mineral trioxide aggregate (MTA) in external root resorption treatment: a clinical case

Objetivos: se describe el tratamiento de una pieza dentaria que presenta reabsorción cemento-dentinaria externa (RCDE) como consecuencia de un traumatismo ocurrido hace veinticinco años. Caso clínico: la resolución se completó en dos etapas. En la primera, dado que se observó una obturación incorrecta, se realizó el retratamiento endodóntico y se obturó con conos de gutapercha y sellador Sealer 26. En la sesión siguiente, se levantó un colgajo con el objetivo de exponer y explorar la zona radiolúcida presente en distal de la raíz a la altura del tercio medio. Se realizó un curetaje y se rellenó la cavidad de la reabsorción con trióxido mineral blanco (MTA). La rehabilitación estética de la corona fue realizada con una carilla de composite a mano alzada. Después de dos años de haber realizado el tratamiento y en controles radiográficos periódicos, se observó que la RCDE se detuvo. Conclusión: las reabsorciones cemento-dentinarias externas inflamatorias son lesiones relativamente frecuentes luego de un traumatismo dentario. Es importante realizar un diagnóstico temprano para evitar su evolución y la consecuente pérdida de la pieza. El material fue elegido teniendo en cuenta sus propiedades físicas y químicas, entre las que se destacan su baja citotoxicidad, la capacidad de solidificar en presencia de humedad y el estímulo que ejerce sobre la regeneración del ligamento periodontal.