A narrative review of cracks in teeth: Aetiology, microstructure and diagnostic challenges.

OBJECTIVES: To summarize the available evidence of crack formation in teeth and to discuss the limitations of the current clinical diagnostic modalities for crack detection in teeth. BACKGROUND: Cracks are a common clinical finding in teeth and yet clinicians still struggle to identify the full extent and orientation of cracks for their appropriate timely management. The biomechanics of crack development can be due to multiple factors and can differ from an unrestored tooth to a restored or endodontically treated tooth. DATA & SOURCES: This narrative review has been designed following the guidelines published by Green et al. 2006 [1] Published literature in the English language that addresses the objectives of this review up to July 2022 was sourced from online databases and reference lists. The relevance of the papers was assessed and discussed by two reviewers. A total of 101 publications were included in this narrative review. CONCLUSIONS: The initiation and development of cracks in teeth are likely linked to an interplay between the masticatory forces and fracture resistance of the remaining tooth structure. From the identified literature, the quality and quantity of remaining tooth structure in a restored or endodontically-treated tooth affects the biomechanics of crack development compared to an unrestored tooth. The extent, orientation, and size of the cracks do affect a clinician's ability to detect cracks in teeth. There is still a need to develop reliable diagnostic tools that will accurately identify cracks in teeth beneath restorations to enable effective monitoring of their propagation and provide appropriate interventions. CLINICAL SIGNIFICANCE: The development and propagation of cracks in an unrestored tooth differ greatly from a restored and endodontically treated tooth; mainly linked to the quantity and quality of the remaining tooth structure and the forces acting on them. Identifying the extent of cracks in teeth remains challenging for early clinical intervention.

Endodontic Periapical Lesion: An Overview on the Etiology, Diagnosis and Current Treatment Modalities.

Nonsurgical and surgical endodontic treatments have a high success rate in the treatment and prevention of apical periodontitis when carried out according to standard and accepted clinical principles. Nevertheless, endodontic periapical lesions remain in some cases, and further treatment should be considered when apical periodontitis persists. Although several treatment modalities have been proposed for endodontically treated teeth with persistent apical periodontitis, there is a need for less invasive methods with more predictable outcomes. The advantages and shortcomings of existing approaches for the diagnosis and treatment of endodontic periradicular lesions are discussed in this review.

Antimicrobial Photodynamic Therapy in the Endodontic Treatment of Deciduous Teeth: In Vivo Pilot Study

Abstract Objective: To evaluate the Antimicrobial Photodynamic Therapy (aPDT) in infected deciduous teeth by quantifying the viable bacteria in root canal treatment. Material and Methods: Radicular canal cultures were collected (n= 10). Four intra-canal samples were collected at four different times in each of the sampled teeth, as follows: Time 1 (T1), baseline: After opening the pulp-chamber; Time 2 (T2): After application of aPDT; Time 3 (T3): After mechanical, chemical manipulation; Time 4 (T4): After a second application of aPDT. The aPDT was performed with a 4J/cm energy low-intensity diode, together with 0.005% methylene blue as a photosensitizer. The clinical specimens were taken to the laboratory for a bacteria count (colony forming units) and the results were statistically analyzed using the Friedman and Wilcoxon tests, with a significance level of α=0.05. Results: Statistical differences were seen between the numbers of bacteria at times T1-T2, T1-T3 and T1-T4 on the cultivated plates. However, no significant statistical differences were observed between the number of bacteria in samples T2-T3, T2-T4 and T3-T4. Conclusion: Antimicrobial photodynamic therapy can be a good co-adjuvant in root canal decontamination of necrotic primary teeth.

Evaluation of Tensile Bond Strength of Metallic Prefabricated Posts Cemented with Different Luting Agents

Abstract Objective: To assess the tensile bond strength of prefabricated metal posts cemented with different luting agents. Material and Methods: Fifty single-rooted endodontically treated human teeth had their crowns cut, mounted into acrylic-resin blocks and then an 8mm depth post space were prepared. Prefabricated cylindrical metal posts were cemented using different luting agents: a zinc phosphate cement (SS White), a conventional glass ionomer cement (Vidrion C), two resin-modified glass ionomer cements (Vitremer and RelyX Luting 2) and a resin cement (RelyX ARC). Samples were stored in distilled water for seven days and then submitted to a tensile bond strength test until complete dislocation of the post. One-way analysis of variance and Tukey test for pairwise multiple comparisons were used to evaluate differences between luting agents. Results: Tensile bond strength was 563.88±203.41 N for zinc phosphate cement, 336.86 ± 137.64 N for Vidrion C, 515.24 ± 239.48 N for Vitremer, 828.47±433.99 N for RelyX Luting 2 and 1262.51 ± 356.29 for RelyX ARC. The Relyx ARC presented the highest tensile bond strength regard the luting agent tested (p< 0.05). Conclusion: RelyX ARC presented the higher tensile bond strength compared to the other luting agents evaluated.

In vivo study of the effectiveness of quantitative percussion diagnostics as an indicator of the level of structural pathology of teeth after restoration.

STATEMENT OF PROBLEM: Conventional diagnostic aids based upon imagery and patient symptoms do not indicate whether restorative treatments have eliminated structural pathology. PURPOSE: The purpose of this clinical study was to evaluate quantitative percussion diagnostics (QPD), a mechanics-based methodology that tests the structural integrity of teeth noninvasively. The study hypothesis was that QPD would provide knowledge of the structural instability of teeth after restorative work. MATERIAL AND METHODS: Eight participants with 60 sites needing restoration were enrolled in an IRB-approved clinical study. Each participant was examined comprehensively, including QPD testing. Each site was disassembled and microscopically video documented, and the results were recorded on a defect assessment sheet. A predictive model was developed for the pathology rating based on normalized fit error (NFE) values using data from the before treatment phase of the study published previously. Each restored site was then tested using QPD. The mean change in NFE values after restoration was evaluated by the pathology rating before treatment. The model was then used to predictively classify the rating after restoration based on the NFE values after treatment. The diagnostic potential of the rating was explored as a marker for risk of pathology after restoration. RESULTS: After restoration, 51 of the 60 sites fell below an NFE of 0.04, representing a greatly stabilized tooth site sample group. Several sites remained in the high-risk category and some increased in pathologic micromovement. Two models were used to determine severity with indicative cutoff points to group sites with similar values. CONCLUSIONS: The data support the hypothesis that QPD can indicate a revised level of structural instability of teeth after restoration.

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)

Electrical Pulp Testing: Sources of Error.

INTRODUCTION: Accurate identification and assessment of an inflamed or necrotic tooth is essentialfor endodontic treatment. The purpose of this research was to investigate possible sources of error associated with the use of the electric pulp tester (EPT). METHODS: Forty-six intact teeth (23 tooth pairs) in 22 patients were evaluated in vivo. For the tooth pairs, one tooth had to have been previously endodontically treated and restored with a class II amalgam restoration. The restoration was required to have proximal contact with a class II amalgam of another vital posterior tooth. EPT was performed on pulpless and vital teeth for experimental groups (enamel, restoration, contacting, or isolated). RESULTS: The highest rate of false positive responses (82%) was found in the pulpless restored contacting group, suggesting that EPT impulses are able to travel through proximal metallic contacts and stimulate teeth distant from the EPT probe. All vital tooth groups had a high rate of positive responses with no significant diferences. CONCLUSIONS: If a tested tooth contains an interproximal restoration contacting adjacent restorations or the gingival, the teeth must be isolated (rubber dam) and the EPT probe should be placed in a region suspected to have uninterrupted tubule paths to the pulp.

Management of an endo-perio lesion in an immature tooth using autologous platelet-rich fibrin: a case report.

Treatment of an endo-perio lesion involving a non-vital young permanent tooth is a highly challenging task to Pediatric Dentists. There is a quest for the newer biological approach to management of these lesions as traditional methods have various disadvantages. Recently, platelet-rich fibrin (PRF), a second-generation platelet concentrate, is rich in growth factors have been used in the periodontal regeneration procedure. The purpose of this paper is to describe the efficacy of PRF in the treatment of a deep intra bony defect associated with an endo-perio lesion in an immature right mandibular first premolar of 12-year-old female patient. A freshly prepared autologous PRF membrane was placed in the bony defect following debridement. Clinical and radiographic follow-up were performed at regular intervals that revealed absence of pain, gain in clinical attachment level, reduction in probing depth, and excellent bone regeneration indicating successful outcome.

A comparative analysis of magnetic resonance imaging and radiographic examinations of patients with atypical odontalgia.

AIMS: To examine (1) the occurrence of magnetic resonance imaging (MRI) signal changes in the painful regions of patients with atypical odontalgia (AO) and (2) the correlation of such findings to periapical bone defects detected with a comprehensive radiographic examination including cone beam computed tomography (CBCT). METHODS: A total of 20 patients (mean age 52 years, range 34 to 65) diagnosed with AO participated. Mean pain intensity (± standard deviation) was 5.6 ± 1.8 on a 0-10 numerical rating scale, and mean pain duration was 4.3 ± 5.2 years. The inclusion criterion was chronic pain (> 6 months) located in a region with no clear pathologic cause identified clinically or in periapical radiographs. In addition to a clinical examination and a self-report questionnaire, the assessments included radiographic examinations (panoramic, periapical, and CBCT images), and an MRI examination. Changes in MRI signal in the painful region were recorded. Spearman's rank correlation between radiographic and MRI findings was calculated. RESULTS: Eight of the patients (40%) had MRI signal changes in the pain region. The correlation to radiographic periapical radiolucencies was 0.526 (P = .003). Of the eight teeth displaying changes in MRI signal, six showed periapical radiolucency in the radiographs. CONCLUSION: MRI examination revealed no changes in the painful region in a majority of patients with AO, suggesting that inflammation was not present. MRI findings were significantly correlated to radiographic findings.

Orthokeratinized odontogenic cysts presenting as a periapical lesion: report of a case and literature review.

INTRODUCTION: Inflammatory cysts, granulomas, abscesses, and fibrous scars represent most periapical radiolucencies. However, other less common lesions, such as orthokeratinized odontogenic cysts (OOCs), can be found at this region, and they deserve to be discussed because the prognosis for an OOC is different from that expected for the ordinary inflammatory periapical diseases. METHODS: An interesting case of OOC associated with a nonvital tooth in a 40-year-old woman is described. After a previous clinical diagnosis of a radicular cyst, the tooth was extracted, and the lesion was enucleated and submitted to microscopy examination. RESULTS: Because of the detection of an orthokeratinized epithelium lining, a diagnosis of OOC was concluded. After 2 years of periodic follow-up, no signs of recurrence were detected. CONCLUSIONS: The presence of keratin in radicular lesions must be carefully evaluated to eliminate the diagnosis of lesions with more aggressive behavior, such as an OOC or even a keratocystic odontogenic tumor. Hence, histopathologic examination is mandatory to confirm the type of lesion and to differentiate other pathologic conditions, therefore establishing patients' prognoses precisely.

Management of the pulp in primary teeth--an update.

Management of the pulpal tissue in primary teeth is a clinical challenge facing dental practitioners on a regular basis. This article reviews the most common treatments used at the present time in the management of the pulp in deciduous teeth. It gives an overview of treatment options and the indications and contra-indications for the different treatment modalities. The evidence behind the medicaments used, their actions and success rates are discussed. Practical guidelines for choosing to retain or extract deciduous teeth and management of the primary tooth pulp with different clinical presentations are discussed. Areas of future research are highlighted.

Acute apical periodontitis and vertical root fracture of the same tooth: a case report.

Vertical root fracture is a frequent complication in endodontically treated teeth and usually leads to extraction of the affected tooth. Differential diagnosis may be difficult, especially in patients with periodontal and endodontic disease. This case report describes the diagnosis and clinical and radiographic features of apical periodontitis and vertical root fracture of the same tooth, which were separated by an interval of several years. Vertical root fracture of the mesial root was diagnosed with the help of an exploratory flap and microscopic observation.

Supernumerary lateral incisor.

Supernumerary teeth are common in general population and occur frequently in patients with familial trait. However, it is rare to find supernumeraries in individuals with no associated disease or syndrome. Supernumerary teeth are found in any region of maxilla and mandible, with a predisposition for anterior maxilla. A case of endodontically involved supernumerary lateral incisor is described.

A novel diagnostic and prognostic classification for the clinical management of endodontically treated single anterior teeth.

The restoration of endodontically treated anterior teeth (ETAT) may pose a significant clinical challenge given the wide variety of therapeutic options available. Accurate analysis of the remaining tooth structure is critical in the diagnostic process, leading to selection of the proper treatment option. A novel, simple, and precise classification that allows the evaluation of ETAT is presented. Important factors related to the crown or abutment such as height, wall thickness, and circumferential integrity and root-related factors such as diameter of the canal, depth of the preparation, and canal shape are discussed. This classification may serve to establish a comprehensive diagnosis and assign prognosis to ETAT, which may be helpful for interclinician communication and standardized comparisons in clinical research.

Comparison of the efficacy of a custom-made pulse oximeter probe with digital electric pulp tester, cold spray, and rubber cup for assessing pulp vitality.

INTRODUCTION: The ideal technique for the evaluation of pulp vitality should be noninvasive, painless, objective, reliable, and reproducible. To achieve this, the most routine tests are sensitivity tests. However, a major shortcoming with these tests is that they indirectly indicate pulp vitality by measuring a neural response. Pulse oximetry is a well-established oxygen saturation monitoring technique broadly used in medicine. However, its efficacy as the pulp vitality test should be evaluated. The aim of this study was to design and build a custom-made pulse oximeter dental probe and to evaluate its efficacy in comparison with electric pulp tester, cold spray, and a rubber cup in pulp vitality testing. METHODS: Twenty-four single-canal mandibular premolars needing endodontic treatment were selected. The patients did not have systemic disease and did not consume drugs. Also, they had no clinically relevant signs of necrosis. The selected teeth were pulpally tested with 4 kinds of tests including pulse oximetry, the electric test, cold spray, and the rubber cup. After endodontic treatment of these teeth, which revealed the actual status of the pulp, the results were analyzed by the kappa test to show the efficacy of these tests. RESULTS: When comparing electric, cold, heat, and pulse oximeter tests with the gold standard, the kappa agreement coefficient was 18%, 18%, 14%, and 91%, respectively. The sensitivity of pulse oximetry, a rubber cup, electric test, and cold spray was 0.93, 0.60, 0.60, and 0.53, respectively. The specificity of these tests was 1.00, 0.55, 0.22, and 0.66, respectively. CONCLUSIONS: Pulp testing by using pulse oximetry is more reliable than the electric test, rubber cup, and cold spray. The custom-made pulse oximeter dental probe is an effective and objective method for pulp vitality assessment.

The diagnostic challenge of vertical root fracture in endodontically treated teeth: a case report / O desafio diagnóstico de fratura radicular vertical em dentes endodonticamente tratados: relato de caso

PURPOSE: To present the diagnostic challenge of a clinical case of vertical root fracture (VRF) in an endodontically treated mandibular left lateral incisor and discuss the diagnostic methods employed to achieve the conclusive diagnosis. CASE DESCRIPTION: At 16 months after endodontic treatment, a 60-year-old female patient reported pain during mastication. Clinically, she presented with an active distolingual fistula and a probing depth of 9 mm on the distal aspect of tooth 32. A radiographic examination indicated pear-shaped distal bone loss. The fistula was mapped, which confirmed that the lesion had a periodontal origin. A diagnostic hypothesis of a VRF was established. Exploratory surgery revealed the VRF on the distolingual aspect of the root without separation of the root fragments. CONCLUSION: Knowledge of the diagnostic aspects and the correct interpretation of radiographic images was enough to establish the diagnostic hypothesis of a VRF. However, the conclusive diagnosis was only confirmed during exploratory surgery.

OBJETIVO: Apresentar o desafio de diagnosticar Fratura Radicular Vertical (FRV) em um incisivo lateral inferior esquerdo tratado endodonticamente e discutir os métodos diagnósticos empregados para obtenção do diagnóstico conclusivo. DESCRIÇÃO DO CASO: Após 16 meses do término do tratamento, a paciente relatou dor à mastigação. Clinicamente apresentava uma fístula disto-lingual ativa e profundidade de sondagem de 9-mm na face distal do dente 32. Radiograficamente apresentava perda óssea distal em forma de "pêra". Foi realizado o mapeamento da fístula, confirmando tratar-se de uma lesão de origem periodontal. Estabeleceu-se a hipótese diagnóstica de FRV. Para a confirmação do diagnóstico realizou-se cirurgia exploratória. Foi constatada a FRV na face disto-lingual da raiz sem o afastamento dos fragmentos radiculares. CONCLUSÃO: Concluiu-se que o conhecimento dos achados semiotécnicos e a correta interpretação das imagens radiográficas foram suficientes para se estabelecer a hipótese diagnóstica de FRV. Entretanto, o diagnóstico conclusivo só foi confirmado durante a cirurgia exploratória.

Evaluation of accuracy, reliability, and repeatability of five dental pulp tests.

INTRODUCTION: The aim of this study was to compare the clinical accuracy, reliability, and repeatability of laser Doppler flowmetry (LDF), an electric pulp test (EPT), and various thermal pulp sensibility tests. METHODS: Pulp tests were done on 121 teeth in 20 subjects by using LDF, EPT, and thermal pulp testing (CO(2), Endo Frost [EF], Ice) during 2 or 3 test sessions with at least 1-week intervals. The order of testing was reversed on the second visit. A laser Doppler flowmeter was used to measure mean pulp blood flow (Flux) calibrated against a brownian motion medium and zeroed against a static reflector. The laser source was 780 nm, with 0.5-mm fiber separation in the probe, 3.1 kHz as the primary bandwidth for filter set to 0.1-second time output constant. Customized polyvinylsiloxane splints were fabricated for each participant, and a minimum of 90-second recording time was used for each tooth. Raw data were analyzed by using repeated measure analysis of variance, pairwise comparisons, and interclass correlations (ICC). RESULTS: The accuracy of EPT, CO(2), and LDF tests was 97.7%, 97.0%, and 96.3%, respectively, without significant differences (P > .3). Accuracy of EF and Ice was 90.7% and 84.8%, respectively. EPT (P = .015) and CO(2) (P = .022) were significantly more accurate than EF. LDF was more accurate than EF, but this was not statistically significant (P = .063). Ice was significantly less accurate than EPT (P = .004), CO(2) (P = .005), LDF (P = .006), and EF (P = .019). With the exception of Ice (effect of visit: F(2,38) = 5.67, mean squared error = 0.01, P = .007, η(2)(p) = 0.23), all tests were reliable. Ice (ICC = 0.677) and LDF (ICC = 0.654) were the most repeatable of the tests, whereas EPT (ICC = 0.434) and CO(2) (ICC = 0.432) were less repeatable. CONCLUSIONS: CO(2), EPT, and LDF were reliable and the most accurate tests, but CO(2) and EPT were less repeatable yet less time-consuming than LDF. EF was reliable but not as accurate as EPT and CO(2) and less repeatable than Ice and LDF. Ice was the most repeatable but the least accurate and least reliable test.

The ability of pulp sensibility tests to evaluate the pulp status in primary teeth.

BACKGROUND. Accurate determination of the pulp status is the most important part of conservative pulp therapy. AIM. The aim of this study was to assess the ability of thermal and electrical pulp tests to assess the pulp status in primary teeth. DESIGN. Seventy-eight primary molar teeth in 36 children were investigated. Fifty-six teeth had unknown pulp status in need of endodontic treatment, and 22 were intact teeth with no signs of pulp disease. Cold, hot and electrical pulp testing (EPT) were performed on each tooth. The gold standard was established by direct inspection of the pulp after an access cavity had been made. The sensitivity, specificity, positive and negative predictive values for each test and different sequential combinations of pulp testing were calculated. Sequential combination test analysis was used for data analysis. RESULTS. The highest accuracy was found for EPT, followed by heat and cold tests. No significant difference was found between the accuracy of EPT and the heat test (P-values > 0.05); however, the accuracy of EPT was significantly higher than that of the cold test (P-value< 0.05). CONCLUSION. Based on this study, EPT can be used as a reliable test for diagnosing the pulp status in primary teeth.