Lesiones perirradiculares persistentes: revisión narrativa / Persistent periradicular lesions: a narrative review

La persistencia de lesiones perirradiculares luego del tra- tamiento endodóntico es un problema que requiere del clínico un conocimiento cabal de la histofisiología y de la histopato- logía del sistema de conductos radiculares del tejido pulpar y de los tejidos perirradiculares (periodonto y hueso); además de considerar siempre la posible existencia de enfermedades sistémicas que también pueden actuar como factores de in- fluencia. La presencia de bacterias remanentes a posteriori del tratamiento es considerada como una de las causas principales y más frecuentes para la perpetuación de las lesiones perirra- diculares. Sin embargo, existen otros factores causales, como la existencia de conductos laterales o accesorios infectados y no tratados, la reabsorción dentinaria interna, intercomunica- ciones, cul-de-sacs o istmos; que representan áreas de difícil acceso durante la instrumentación e irrigación. Cuando la cau- sa original se localiza en la zona perirradicular, como en los casos de actinomicosis, reacciones a cuerpo extraño, cristales de colesterol (CRCo) y granulomas o quistes con alto conte- nido de CRCo, la indicación más adecuada es el retratamiento y la cirugía periapical como complemento (AU)

The persistence of periradicular lesions after endodontic treatment is a problem that requires the doctor to have a thor- ough knowledge of the histophysiology and histopathology of the root canal system, the pulp tissue and periradicular tis- sues (periodontium and bone); as well as always considering the possible existence of systemic alterations that can also be influencing factors. Persisting bacteria within the root canal system after treatment is one of the major and most frequent causes for the perpetuation of periradicular lesions. Howev- er, there are other possible causal factors such as the exist- ence of untreated lateral or accessory canals, internal dentin resorption, intercommunications, cul-de-sacs or isthmuses; areas that represent a difficulty in access during instrumen- tation and irrigation. If the original cause is located in the periradicular area, in cases like actinomycosis, foreign-body reactions, cholesterol crystals (CRCo) and granulomas or cysts with high content of CRCo, retreatment coupled with periapical surgery is the best approach to treatment (AU)

Noninvasive Endodontic Periapical Biopsy of a Periapical Fibrous Scar: Case Report.

Postendodontic periapical fibrous scars (PFScs) comprise a type of radiolucent healing that is frequently misinterpreted as a pathological lesion. A combined clinical, radiologic, and histologic correlation is essential for a reliable diagnosis. This report presents a case of a patient with a long-term persistent asymptomatic postendodontic radiolucency that was misdiagnosed as endodontic failure and referred for endodontic retreatment and periapical surgery. To reach a definitive diagnosis, a core bone biopsy needle (CBBn) technique was performed on the area of the radiolucency. The material obtained was processed for histologic analysis and the lesion was determined to be a PFSc. In conclusion, the use of a CBBn before any invasive treatment allowed the clinician to distinguish between PFSc and other persisting pathosis, such as periapical granuloma or cystic lesions.

Relationship between hypertension and periapical lesion: an in vitro and in vivo study.

The aim of this study was to compare potential aspects of periapical lesion formation in hypertensive and normotensive conditions using hypertensive (BPH/2J) and wild-type control (BPN/3J) mice. The mandibular first molars of both strains had their dental pulp exposed. At day 21 the mice were euthanized and right mandibular molars were used to evaluate the size and phenotype of apical periodontitis by microCT. Proteins were extracted from periapical lesion on the left side and the expressions of IL1α, IL1ß and TNFα were analyzed by ELISA. Bone marrow stem cells were isolated from adult mice femurs from 2 strains and osteoclast differentiation was evaluated by tartrate-resistant acid phosphatase (TRAP) in vitro. The amount of differentiated osteoclastic cells was nearly double in hypertensive mice when compared to the normotensive strain (p < 0.03). Periapical lesion size did not differ between hypertensive and normotensive strains (p > 0.7). IL1α, IL1ß and TNFα cytokines expressions were similar for both systemic conditions (p > 0.05). Despite the fact that no differences could be observed in periapical lesion size and cytokines expressions on the systemic conditions tested, hypertension showed an elevated number of osteoclast differentiation.

Immediate and mediate furcal perforation treatment in primary molars: 24-month follow-up.

BACKGROUND: Furcal perforation consists of a communication between the pulp cavity and the periodontal tissues that can occur accidentally during cavity preparation or root canal instrumentation. This complication may lead to inflammatory reactions and compromise adjacent tissues irreversibly, resulting in the early loss of primary teeth. Perforation sealing with a biocompatible material is necessary to ensure a favourable prognosis. Among different materials, MTA has been employed due to its excellent healing and physical properties. CASE REPORT: The purpose of these case reports was to describe immediate and mediate cases of furcal perforation treatment using MTA in primary molars. In both the cases, after accidental perforation detection, the pulp chamber was cleaned with saline solution to clear off the debris. The wound surface was continuously irrigated with saline solution and a dry sterile cotton pellet was placed on the radicular pulp stumps and perforation area with slight pressure until the bleeding was controlled. The MTA was applied into the perforation and pulp chamber area with the aid of a sterile amalgam carrier. The teeth were restored with resin-modified glass ionomer cement. FOLLOW-UP: Clinical and radiographic follow-up examinations were carried out at 3, 6, 12, 18, and 24 months after perforation sealing. Both the cases remained asymptomatic, presenting no discomfort, mobility, swelling, or fistula after 24-months follow-up. Radiographically, the radiolucent area disappeared as a result of bone formation in the inter-radicular space, showing adjacent tissue preservation. CONCLUSION: Thus, MTA may be considered as an ideal option for conservative treatment of immediate and mediate furcal perforation in primary teeth, once it promoted repair with tooth maintenance in both the cases.

Relationship between hypertension and periapical lesion: an in vitro and in vivo study

Abstract The aim of this study was to compare potential aspects of periapical lesion formation in hypertensive and normotensive conditions using hypertensive (BPH/2J) and wild-type control (BPN/3J) mice. The mandibular first molars of both strains had their dental pulp exposed. At day 21 the mice were euthanized and right mandibular molars were used to evaluate the size and phenotype of apical periodontitis by microCT. Proteins were extracted from periapical lesion on the left side and the expressions of IL1α, IL1β and TNFα were analyzed by ELISA. Bone marrow stem cells were isolated from adult mice femurs from 2 strains and osteoclast differentiation was evaluated by tartrate-resistant acid phosphatase (TRAP) in vitro. The amount of differentiated osteoclastic cells was nearly double in hypertensive mice when compared to the normotensive strain (p < 0.03). Periapical lesion size did not differ between hypertensive and normotensive strains (p > 0.7). IL1α, IL1β and TNFα cytokines expressions were similar for both systemic conditions (p > 0.05). Despite the fact that no differences could be observed in periapical lesion size and cytokines expressions on the systemic conditions tested, hypertension showed an elevated number of osteoclast differentiation.

Long-term evaluation and clinical outcomes of children with dental transplants in Temuco city, Chile.

AIM: To assess the clinical and radiographic outcomes of 36 transplanted teeth and the possible factors affecting the results. MATERIALS AND METHODS: In 26 children, 36 teeth transplants were performed. The main reason for transplantations was the loss of anterior teeth due to trauma; 80.5% of transplanted teeth were immature bicuspids. The transplants were clinically and radiolographycally monitored in respect of pulp vitality, root canal obliteration, periradicular changes and root formation. Fisher Exact Test and Kaplan-Meier analyses were performed to determine the association between the variables and estimation of survival rates, respectively. RESULTS: Thirty (83.3%) of the transplantations were recorded as successful and six as unsuccessful (16.7%). The survival rate was 97.2% during average time of 47.5 months ± 27.8 SD. Only one tooth had been extracted and 5 had survived in not ideal conditions. The majority of immature transplanted teeth developed pulp canal obliteration. CONCLUSION: Factors associated to successful outcome were immature root formation of donor tooth and short flexible splinting period. The main factor associated to failure was replacement resorption. The surgical technique did not present statistical significance in the clinical outcome. Tooth transplantation has shown high success and survival rates, and should be considered as a real option in growing patients.

Endodontic-related facial paresthesia: systematic review.

Paresthesia is a neurosensitivity disorder caused by injury to the neural tissue. It is characterized by a burning or twinging sensation or by partial loss of local sensitivity. Paresthesia related to endodontic treatment can occur because of extravasation of filling material or the intracanal dressing, as a consequence of periapical surgery or because of periapical infection. A literature review of paresthesia in endodontics was undertaken, with a view to identifying and discussing the most commonly affected nerves, the diagnostic process and the treatment options. Among reported cases, the most commonly affected nerves were those passing through the jaw: the inferior alveolar nerve, the mental nerve and the lingual nerve. To diagnose paresthesia, the endodontist must carry out a complete medical history, panoramic and periapical radiography, and (in some cases) computed tomography, as well as mechanoceptive and nociceptive tests. To date, no specific treatment for endodontic-related paresthesia has been described in the literature, since the problem may be related to a variety of causes.

A comparative study between cone-beam computed tomography and periapical radiographs in the diagnosis of simulated endodontic complications.

AIM: To compare cone-beam computed tomography (CBCT) with periapical radiography for the identification of simulated endodontic complications. METHODOLOGY: Sixteen human teeth, in three mandibles, were submitted to the following simulated endodontic complications: G1) fractured endodontic file; G2) root perforation; G3) cast post with deviation; G4) external root resorption. Periapical radiographs were taken of each tooth at three different angles, and CBCT scan was taken. One calibrated examiner who was specialized in dental radiology interpreted the images. The results were analysed using the following scoring system: 0 - unidentified alteration; 1 - alteration identified with inaccurate diagnosis; and 2 - alteration identified with accurate diagnosis. Data were analysed using McNemar and Wilcoxon tests (alfa=0.05). RESULTS: In the overall assessment, CBCT was superior when compared with periapical radiographs (P<0.05). When individual results on each complication were evaluated, CBCT was superior only in the identification of external root resorption (100% Score 2) (P<0.05). CONCLUSION: Cone-beam computed tomography could be an alternative to periapical radiographs especially in the detection and assessment of external root resorption.

Map-reading strategy to diagnose root perforations near metallic intracanal posts by using cone beam computed tomography.

INTRODUCTION: To determine the diagnostic hypothesis on the basis of periapical radiography (PR) is a great challenge for radiologists and endodontists. Visualization of three-dimensional structures, available with cone beam computed tomography (CBCT), favors precise definition of the problem and treatment planning. However, metallic artifact effect of intracanal posts might also induce untrue images. The aim of this article is to suggest a map-reading strategy to diagnose root perforations near metallic intracanal posts (ICPs) by using CBCT. METHODS AND RESULTS: The incapacity to locate correctly the position of root perforation might lead to clinical failures. One strategy to minimize metallic artifact in root perforation associated with ICP is to obtain sequential axial slices of each root, with an image navigation protocol from coronal to apical (or from apical to coronal), with axial slices of 0.2 mm/0.2 mm. This map reading provides valuable information showing dynamic visualization toward the point of communication between the root canals and the periodontal space, associated with radiolucent areas, suggesting root perforation. CONCLUSIONS: The accurate management of CBCT images might reveal abnormality that is unable to be detected in conventional PR. A map-reading approach reduces problems related to detection of root perforations near metallic artifacts. The final diagnosis should always be made in conjunction with the clinical findings.

Radiographic parameters of quality of root canal fillings and periapical status: a retrospective cohort study.

INTRODUCTION: The aim of this study was to radiographically evaluate the relationship between the quality parameters of root canal fillings (apical extension, homogeneity, and taper) and periapical status. In addition, groups of teeth and complicating factors of endodontic treatment were assessed. METHODS: This retrospective cohort study assessed the quality and periapical status of root-filled canals in a 4- to 7-year follow-up period. Each parameter was dichotomized into ideal and altered conditions. A root-filled canal with an ideal condition for all 3 parameters was considered perfect, whereas the loss of 1 or more ideal conditions defined satisfactory or deficient fillings, respectively. The periapical statuses at baseline and follow-up were classified as normal, slight widening of the apical periodontal ligament, or periapical lesion. RESULTS: A total of 291 root-filled canals were evaluated. The prevalence of perfect, satisfactory, and deficient fillings was 54.6%, 37.5%, and 7.9%, respectively (P < .05). The periapical status at follow-up showed normal, slight widening of the apical periodontal ligament, or periapical lesion in 69.8%, 19.2%, and 11% of the roots, respectively (P < .05). The multivariate logistic regression showed that only preoperative periapical lesions (odds ratio, 2.99; 95% confidence interval, 1.27-7.03) and altered tapers (odds ratio, 3.73; 95% confidence interval, 1.51-9.24) were significantly associated with postoperative periapical lesions. CONCLUSIONS: Radiographic parameters of the quality of root-filled canals showed a significant relationship with the periapical status. Nevertheless, an altered taper was the main factor associated with the maintenance or development of periapical lesions after 4- to 7-year follow-up period.

Association of crown discoloration and pulp status in traumatized primary teeth.

The aim of the present study was to determine the association of tooth discoloration in traumatized primary teeth with clinical and radiographic signs of pulp necrosis, and pulp status at the time of endodontic access. Clinical and radiographic data from dental reports of the 47 patient charts of the Trauma Patient Care Program were used totaling 55 teeth that underwent endodontic treatment following the protocol of the Federal University of Santa Catarina (Brazil). The following data were collected: gender, age of child at time of trauma; crown discoloration; abscess and/or fistula; periapical bone rarefaction and/or pathological root resorption; and pulp status at the time of endodontic access. The Chi-square test and logistic regression were used in the statistical analysis. The associations between crown discoloration and gender, age, tooth, type of trauma, clinical alteration, and radiographic alteration were not statistically significant. There was a significant association between crown discoloration and pulp necrosis at the time of endodontic access (χ(2) = 7.672; P < 0.05). Traumatized primary teeth with crown discoloration had a fivefold greater likelihood of exhibiting pulp necrosis than teeth without crown discoloration (95% CI: 1.5-17.1). Thus, a significant association was found between crown discoloration and pulp necrosis in traumatized primary teeth.

Histopathologic and SEM analysis of primary teeth with pulpectomy failure.

OBJECTIVE: The objective of this study was to identify the probable factors associated with pulpectomy failure of primary teeth through qualitative analysis by histopathology (HIST) and scanning electron microscopy (SEM). STUDY DESIGN: A longitudinal clinical investigation of the efficacy of pulpectomy in primary teeth with irreversible pulp changes was carried out with 133 teeth (66 children) evaluated up to 48 months. The overall success was 86.1% during follow-up. Of the 18 teeth extracted as a result of treatment failure, 8 presented sufficiently undamaged roots to be randomly selected for HIST (n = 4) and SEM (n = 4) analysis. RESULTS: Necrotic tissue and chronic inflammatory cells were observed in all specimens submitted to HIST as external radicular resorption associated with Howship's lacunae. SEM analysis showed apical and furcation areas heavily infected with microorganisms and Howship's lacunae. CONCLUSION: These findings suggest that the main factors responsible for pulpectomy failure were technique limitations associated with the morphological irregularities created by external/inflammatory resorption.

Repair of furcal perforation treated with mineral trioxide aggregate in a primary molar tooth: 20-month follow-up.

Furcal perforations may occur during access opening of the pulp chamber or cavity preparation. The perforation can cause an inflammatory reaction in the periodontal ligament. Management of these iatrogenic accidents can pose a significant clinical challenge, mainly when they occur in primary teeth. Current developments in the techniques and materials utilized for root perforation repair have enhanced this procedure's prognosis. Recently, mineral trioxide aggregate (MTA) has been used for several dental purposes. This biocompatible material promotes bone healing and elimination of clinical symptoms. The purpose of this case report was to describe the treatment of a furcal perforation using mineral trioxide aggregate (MTA) in a primary molar tooth. After 20 months, the tooth was asymptomatic. The radiolucent image had disappeared and bone formation at the furcation area had been observed, suggesting healing of the underlying periodontal tissues. Therefore, MTA may be considered an alternative option for the repair of furcal perforation in primary teeth, prolonging the longevity of these dental elements.

Tooth transplantation after dental injury sequelae in children.

Ten immature autotransplanted lower premolars from six patients from 7 to 12 years of age were studied and assessed clinically and radiographically at Regional Clinical Hospital in Temuco between January 2004 and April 2006. All transplantations were performed both because of a missing anterior tooth by dental trauma or by healing complications after injuries. The mean age at the time of the surgery was 10 years (range 7-12 years) and the postoperative follow-up period varied from 5 to 27 months with a mean of 16.9 months. All teeth were stabilized with flexible composite resin wire splints. Within the follow-up period, clinical evaluation was made through percussion and mobility tests. At radiographic evaluation, pulpal canal obliteration (PCO), presence of perirradicular area, inflammatory root resorption (IRR), replacement resorption (RR), stage of root development, lamina dura formation, outline of the periodontal membrane, and arrest in root growth were registered. Pulp healing was observed in 6 of 10 teeth; the other transplanted teeth developed pulp necrosis after 6-8 months possibly related to operative aesthetic procedures. Four teeth showed different grades of PCO at radiographic examination. None of transplanted teeth developed replacement resorption or ankylosis. In this 27-month follow-up period, the survival rate was 100%, regarding aesthetics, function, clinical appearance, and radiographic image of alveolar process.

Relationship between clinical-radiographic evaluation and outcome of teeth replantation.

The aim of this retrospective study was to evaluate clinical and radiographic results related to avulsed and replanted teeth in patients who sought treatment at the Dental Trauma Center of the Dental School of Piracicaba, State University of Campinas, Piracicaba, SP, Brazil. One hundred replanted teeth were studied from 48 individuals (18 females and 30 males, with a mean age of 15 years and 9 months). Post-replantation factors (clinical and radiographic) were observed. The clinical aspects evaluated were crown discoloration, pulp necrosis, mobility changes, presence of fistulae and tooth infra-position. Radiographic examination aimed to identify replacement and inflammatory root resorptions, pulp canal obliteration and the presence of radiolucent areas. Depending on clinical and radiographic findings, results were classified as: complete success, acceptable success, uncertain success or failure. During anamnesis, other factors such as stage of root formation, period extra-alveolar, storage medium, type of splintation, and period after replantation time were recorded. The data obtained were statistically analyzed in order to determine the relationship between the post-replantation factors and outcome of teeth replantation. Linear logistic regression revealed that the majority of replanted teeth were associated with root resorptions and its occurrence duplicated proportionally as the time after replantation increased. Based on these findings, replantation procedures must be submitted to an accurate follow-up, as the success of replanted teeth, which already tends to be limited, may be even more jeopardized if cases are not controlled.

Uso de cortes semi-seriados no diagnóstico das lesões inflamatórias periapicais / Using of step-serial sections in the diagnosis of periapical inflammatory lesions

A prevalência das patologias periapicais é um assunto de discordância entre investigadores. A variação dos achados pode ser atribuída à falta de padronização do material coletado, a diferentes técnicas de processamento do espécime e aos critérios de diagnóstico histológico utilizados por cada investigador. Este trabalho teve como objetivo re-avaliar casos de abscessos periapicais através de cortes semi-seriados. Foram selecionados casos de diagnóstico histopatológico de abscessos periapicias do Laboratório de Patologia Bucal da FOPUCRS, no período de abril/01 a setembro/2002 (18 meses). Os respectivos blocos de parafina foram localizados no arquivo e três novos cortes semi-seriados (com um espaçamento de 20mm entre cada corte) foram realizados. Os cortes foram corados com hematoxilina e eosina e avaliados por dois examinadores. Dos 23 casos de abscessos diagnosticados por ambos avaliadores, 18 (78,3 porcento) mantiveram o diagnóstico inalterado, enquanto que, cinco (21,7 porcento) alteraram o diagnóstico para cisto. Com base na metodologia empregada nesse experimento, concluímos que a utilização de cortes semi-seriados se faz necessária para o correto diagnóstico das lesões inflamatórias periapicais. Entretanto, a utilização desse recurso não minimizará as diferenças existentes entre os estudos de prevalência das lesões inflamatórias periapicais, uma vez que, ainda existe discrepância de critérios de diagnóstico histopatológicos entre os investigadores

Radiographic analysis of the development of periapical lesions in normal rats, sialoadenectomized rats and sialoadenectomized-immunosuppressed rats.

The purpose of this study was to investigate and to compare radiographically the development of periapical lesions in the lower left first molar of normal rats, sialoadenectomised rats and sialoadenectomised-immunosuppressed rats. Sixty male Wistar rats, weighing from 170 to 200 g were utilized. The animals were divided equally into three groups: group I--20 normal rats; group II--20 sialoadenectomised rats; and group III--20 sialoadenectomised-immunosuppressed rats. Groups II and III were sialoadenectomized using the modified Cheyne technique. After 2 weeks, group III was submitted to a immunosuppression regimen by daily subcutaneous cyclosporin A injection (10 mg/kg body weight). After 1 week of immunosuppression for this group, the pulps of all the animals (group I, II and III) were exposed to the oral cavity, to produce apical periodontitis. Five animals of each group were killed 7, 14, 21 and 28 days after pulpal exposure. Their mandibles were surgically removed and radiographically analysed. The lesions were measured using 'Global Lab Image' software. The results showed predictable growth of the lesions during the experimental period. No significant difference was observed between the groups. It was concluded that possible changes in the oral flora and in the host immune response due to xerostomia associated or not to the immunosuppression did not alter the development of the periapical lesions in rats.

In vivo antimicrobial activity of 2% chlorhexidine used as a root canal irrigating solution.

The aim of the present study was to evaluate the in vivo antimicrobial activity of 2% chlorhexidine gluconate (FCFRP-USP) used as a root canal irrigating solution in teeth with pulp necrosis and radiographically visible chronic periapical reactions. Culture techniques and measurement of the inhibition zone were used. Twenty-two root canals of incisors and molars of 12 patients were used. After accessing the canal, the first root canal sample was collected with two sterile paper points that were transferred to a tube containing reduced transport fluid. The root canal was instrumented using chlorhexidine solution. A small sterile cotton pellet was placed at the root canal entrance, and the cavity was sealed with zinc oxide-eugenol cement. The canals were maintained empty for 48 h. Three sterile paper points were then introduced to absorb the root canal fluid (second sample). One paper point was placed on an agar plate inoculated with Micrococcus luteus ATCC 9341 and incubated for 24 h at 37 degrees C, and the other two were submitted to microbiological evaluation. Present in 10 cases at baseline, mutans streptococci was reduced by 100% at the second assessment. Treatment showed an efficiency of 77.78% for anaerobic microorganisms at the second assessment. These data suggest that chlorhexidine prevents microbial activity in vivo with residual effects in the root canal system up to 48 h.