Induction of root development and apical closure in permanent mandibular molar with irreversible pulpitis through total pulpotomy with application of mineral trioxide aggregate / Inducción del termino de desarrollo radicular y cierre apical en molar mandibular permanente con pulpitis irreversible a través de pulpotomía total con aplicación de agregado de trióxido mineral

Loss of teeth vitality when root formation is incomplete, results in weaker structures leaving them prone to fractures and unfavourable long-term prognosis. Apexogenesis is currently the treatment of choice in immature teeth and is indicated in vital teeth without pulpal pathologies. The treatment aims to eliminate the causal agent of the damage, and provide the necessary conditions to preserve vitality in the tooth and induce apical root closure. A 6-year-old male patient was treated at the Endodontics Clinic, Universidad de La Frontera upon complaining of acute pain in tooth 30. The tooth presented incomplete root development due to dental caries with pulp exposure and a diagnosis of irreversible symptomatic pulpitis. Total pulpotomy was performed with the application of Mineral Trioxide Aggregate and controlled at 1, 4, 6, 7 and 12 months, achieving root development and apical closure in the permanent molar. The result was comparable with studies that support this therapy in teeth with irreversible pulpitis. This work seeks to contribute to the existing evidence on the management of immature permanent teeth with irreversible pulpitis to induce root development and apical closure, and maintain pulp vitality.

La pérdida de vitalidad en dientes con formación radicular incompleta trae como resultado el debilitamiento de estos, dejándolos propensos a fracturas con un desfavorable pronóstico a largo plazo. Las terapéuticas actuales de regeneración pulpar en dientes inmaduros estan principalmente indicadas en cuadros de pulpitis irreversible y buscan eliminar el agente causal de daño y brindarle al diente las condiciones y estímulos necesarios para preservar vitalidad e inducir el cierre apical radicular. Un paciente de 6 años de edad y de sexo masculino, acude a la Clínica de Especialidad de Endodoncia de la Universidad de la Frontera, consultando por un dolor agudo en diente 4.6 el cual presentaba un desarrollo radicular incompleto producto de una caries con exposición pulpar con diagnóstico de Pulpitis Irreversible Sintomática. Se realiza una pulpotomia total con aplicación de Mineral Trioxide Aggregate y se controla a los 1, 4, 6 y 7 meses obteniendo un interesante resultado comparable con estudios que avalan dicha terapeutica en dientes con pulpitis irreversible. Este trabajo busca contribuir a la evidencia existente sobre el manejo de dientes permanentes inmaduros con cuadros de pulpitis irreversible para inducir el desarrollo radicular, cierre apical y mantener vitalidad pulpar.

Influence of pregnancy on the inflammatory process following direct pulp capping: a preliminary study in rats

Abstract The purpose of this study was to evaluate the inflammatory process following direct pulp capping during pregnancy. This experimental study involved 48 maxillary first molars of female Wistar rats. The procedures were performed in pregnant and non-pregnant animals (n =20 each). Direct pulp capping with mineral trioxide aggregate (MTA) and restoration with a light-cured resin composite was performed in half of exposed pulp specimens. In the other half of specimens, light-cured composite was placed directly on the exposed pulp. In the control groups (n=4 each), no intervention was performed. Animals were euthanized at 3 and 7 days. All sections (three per slide) were viewed under an optical microscope. One previously calibrated pathologist performed descriptive analysis and assigned scores for inflammatory response and tissue organization adjacent to the pulp exposure. The Kappa value for intra-examiner variability was 0.91. At 3 days, in animals treated with MTA, inflammatory infiltrate was absent in non-pregnant animals while mild inflammatory infiltrate was observed in some pregnant animals. The inflammatory response ranged from mild to severe in both groups treated with composite alone. At 7 days, the inflammatory response was more intense in pregnant than in non-pregnant animals treated with MTA; while this difference were not evident in animals treated with composite alone. In conclusion, pregnancy may not influence the inflammatory process following direct pulp capping with light-cured resin composite, which was always harmful to the pulp; while the tissue response after the direct pulp with MTA were more favorable in non-pregnant animals.

Resumo O objetivo deste estudo foi avaliar o processo inflamatório do tecido pulpar após o capeamento pulpar direto, realizado durante a gestação. Este estudo experimental envolveu 48 primeiros molares superiores de ratos Wistar fêmeas. Os procedimentos foram realizados em animais prenhes e não prenhes (n=20). Após as exposições pulpares, o capeamento pulpar direto foi efetuado com agregado trióxido mineral (MTA) ou restauração direta com resina composta. Nos grupos controle (n=4), nenhuma intervenção foi realizada. Os animais foram submetidos à eutanásia após 3 e 7 dias. Todos os cortes foram avaliados através de um microscópio ótico. Um patologista previamente calibrado realizou analise histológica descritiva e estabeleceu escores para intensidade da resposta inflamatória e para o grau de organização tecidual na região adjacente à exposição pulpar. O valor de Kappa intra-examinador foi 0,91. No período experimental de 3 dias, nos animais tratados com MTA, o infiltrado inflamatório estava ausente nos não prenhes, enquanto infiltrado inflamatório moderado estava presente nos animais prenhes. A resposta inflamatória variou de moderada a severa em ambos os grupos tratados apenas com resina composta. Após o periodo experimental de 7 dias, a resposta inflamatória foi mais intensa nos animais prenhes que nos não prenhes do grupo do MTA, enquanto esta diferença não foi tão evidente nos animais que receberam capeamento pulpar direto com resina composta. Pode-se concluir, que a gestação pode não exercer influência no processo inflamatório do tecido pulpar após proteção pulpar direta com resina composta; a qual foi sempre danosa aos tecidos pulpares. No entanto, a resposta tecidual ao capeamento pulpar com MTA foi mais favorável nos animais não prenhes.

Clinical, radiographic and histological evaluation of primary teeth pulpotomy using mta and ferric sulfate

Abstract The aim of this study was to evaluate the clinical, radiographic and histological outcomes of the dentin-pulp complex from primary molars after pulpotomy with mineral trioxide aggregate (MTA) and 15.5% ferric sulfate (FS). Thirty-one primary molars were randomly allocated into MTA or FS groups. Clinical and radiographic evaluations were recorded at 3-, 6-, 12- and 18-month follow-up. Teeth at the regular exfoliation period were extracted and processed for histological analysis. Clinical and radiographic data were tested by statistical analysis (p≤0.01). Histological outcomes were analyzed descriptively. All of the treated teeth presented clinical success over the experimental periods. Both groups exhibited 100% of radiographic success at 3, 6 and 12 months. At the 18-month follow-up, one tooth from FS group presented inter-radicular radiolucency (p>0.01). Histologically, the treated teeth presented pulp vitality and absence of inflammatory infiltrate into the connective tissue. Only MTA group showed hard tissue barrier surrounded by odontoblasts over the pulp stumps. Both MTA and 15.5% FS are effective for pulpotomies of primary teeth. Although MTA is considered the first-choice material, FS may be a suitable alternative when treatment cost is an issue.

Resumo O objetivo deste estudo foi avaliar os resultados clínicos, radiográficos e histológicos do complexo dentino-pulpar de molares decíduos após pulpotomia com agregado trióxido mineral (MTA) e sulfato férrico (SF) 15,5%. Trinta e um molares decíduos foram alocados aleatoriamente nos grupos MTA ou SF. As avaliações clínicas e radiográficas foram realizadas aos 3, 6, 12 e 18 meses de acompanhamento. Os dentes no período regular de esfoliação foram extraídos e processados ​​para análise histológica. Os dados clínicos e radiográficos foram analisados estatisticamente (p≤0,01). O resultados histológicos foram analisados ​​descritivamente. Todos os dentes tratados apresentaram sucesso clínico ao longo dos períodos experimentais. Ambos os grupos exibiram 100% de sucesso radiográfico aos 3, 6 e 12 meses. Aos 18 meses de acompanhamento, um dente do grupo SF apresentou radiolucidez interradicular (p>0,01). Histologicamente, os dentes tratados apresentaram vitalidade pulpar e ausência de infiltrado inflamatório no tecido conjuntivo. Somente o grupo MTA mostrou barreira de tecido duro rodeada por odontoblastos sobre os cotos pulpares. MTA e SF 15,5% são eficazes para pulpotomias de dentes decíduos. Embora o MTA seja considerado o material de primeira escolha, o SF pode ser uma alternativa adequada quando o custo do tratamento é um problema.

Regenerative Endodontic Treatment as a Retreatment Option for a Tooth with Open Apex - A Case Report

Abstract: Treatment of non-vital immature teeth with apical periodontitis has always been a challenge in Endodontics. Regenerative endodontic treatment (RET) has been successfully used for the management of these cases. The aim of this study is to present a case of RET used for the retreatment of a previously endodontically treated permanent tooth with an open apex. A 14-year-old boy with a poor endodontic treatment done on his maxillary right central incisor developed symptomatic apical periodontitis. Radiographically, incomplete root development with thin dentinal walls and an open apex were evident. After accessing and removing previous filling materials, the canal was copiously irrigated with 2.5% sodium hypochlorite. A triple antibiotic paste was placed inside the canal and left for 15 days. After removal of the antibiotic mixture, bleeding was induced into the canal by passing a hand file out of the apex. A collagen membrane barrier was placed over the blood clot, followed by sealing with mineral trioxide aggregate. Access was sealed with permanent filling materials. Clinical examination at 12, 24 and 36 months revealed no symptoms. Radiographic examination showed resolution of the periapical lesion and apical closure. Sensitivity tests with cold and an electric pulp test elicited a negative response at all recall periods. On the basis of long-term results, RET may be an effective option for the retreatment of an immature permanent tooth with a failed previous treatment and periapical periodontitis.

Alteraciones morfológicas del bazo de ratas (rattus norvergicus), tratadas con trióxido de arsénico / Morphological alterations of the spleen of rats (rattus norvegicus) treated with arsenic trioxide

En América Latina la presencia del arsénico en el ambiente y en las fuentes de agua para consumo humano, se debe a factores naturales de origen geológico como a actividades antropogénicas. El arsénico en las aguas naturales se encuentra principalmente como trivalente (arsenito) o pentavalente (arsenato). El objetivo de este trabajo fue determinar las alteraciones que provoca el trióxido de arsénico a nivel de la morfología del bazo de ratas (Rattus norvegicus - Sprague-Dawley). Se utilizaron 24 ratas de ambos sexos de 55 días de vida. Las ratas fueron pesadas y divididas en 3 grupos (4 hembras y 4 machos). Los grupos tratados fueron inyectados con 5 mg y 10 mg de As2O3 respectivamente, en dosis única diaria vía intraperitoneal por 15 días. Al grupo control se le aplicó agua destilada sin arsénico. Después del tratamiento los animales fueron sacrificados por eutanasia convencional y se obtuvo el bazo, los cuales fueron lavados, pesados y seccionados en cuatro partes, que fueron fijadas en formol tamponado al 10 por ciento. Mediante técnica histológica se obtuvieron 4 muestras seriadas de cada bazo, de 5 micrones de espesor con una separación de 100 micrones entre si. Posteriormente fueron teñidas con H-E. Se analizaron 30 campos (120 campos por órgano). Los datos obtenidos permiten concluir que ratas tratadas con trióxido de arsénico, presentan alteración a nivel de los compartimentos del bazo, con un aumento del compartimento de la pulpa roja, una depleción en el tamaño y número de folículos linfoides y de la zona marginal. A su vez, se observó pérdida de la celularidad de la vaina linfoide periarteriolar (PALS).

In Latin America, the presence of arsenic in the environment and water sources for human consumption is due to natural geological factors and anthropogenic activities. Arsenic in natural waters is mainly found as trivalent (arsenite) or pentavalent (arsenate). The aim of this study was to determine the alterations causing arsenic trioxide-level morphology of the spleen of rats (Rattus norvegicus - Sprague-Dawley). Were used 24 rats of both sexes of 55 days of life. The rats were weighed and divided into 3 groups (4 females and 4 males). The treated groups were injected with 5 mg and 10 mg of As2O3 respectively, intraperitoneally daily dosing for 15 days. The control group was administered arsenic-free distilled water. After treatment the animals were euthanized conventionally, and spleen was removed, which was washed, weighed and sectioned into four parts, which were fixed in 10 percent buffered formalin. Histological technique using four serial samples were obtained from each spleen of 5 microns thick with a spacing of 100 microns between them. Subsequently these were stained with H-E. We analyzed 30 fields (120 fields per organ). The data obtained indicates that rats treated with arsenic trioxide have an altered level of the compartments of the spleen, with an increased red pulp chamber, depletion in the size and number of lymphoid follicles and marginal zone. Furthermore, loss of cellularity of periarteriolar lymphoid sheath (PALS) was observed.

Root Reconstructed with Mineral Trioxide Aggregate and Guided Tissue Regeneration in Apical Surgery: A 5-year Follow-up

Apical surgery should be considered as the last treatment option and employed when conventional endodontic treatment does not provide the expected result. In teeth undergoing apical surgery, the type of retrograde filling material is one of the factors interfering with the repair of periapical tissues. The material in intimate contact with the periapical tissues plays a fundamental role in the repair process. Several materials have been studied and indicated for use in apical surgery procedures, but the mineral trioxide aggregate (MTA) is still the most frequently used one. Guided tissue regeneration (GTR) techniques have been proposed as an adjunct to apical surgery to enhance bone healing. Here is reported a clinical case in which apical surgery was performed in conjunction with MTA-based root reconstruction of the maxillary right second incisor. After the apical surgery, a root-end cavity was prepared at the vestibular face of the involved tooth and filled with MTA. A bovine bone graft and a cortical collagen membrane were placed on the bone defect. After 5 years, clinical and radiographic assessments showed that the treatment was successful. It may be concluded that MTA presents favorable characteristics in adverse conditions and can be used in conjunction with GTR in cases involving root reconstruction.

A cirurgia apical deve ser considerada como a última opção de tratamento, e realizada quando o tratamento endodôntico convencional não proporciona o resultado esperado. Em dentes submetidos à cirurgia apical, o tipo de material retro-obturador é um dos fatores que interferem no reparo dos tecidos periapicais. O material em íntimo contato com os tecidos periapicais desempenha um papel fundamental no processo de reparo. Vários materiais têm sido estudados e indicados para o uso em procedimentos de cirurgias apicais, entretanto o agregado de trióxido mineral (MTA) ainda é o mais frequentemente utilizado. A regeneração tecidual guiada (GTR) tem sido proposta como um auxiliar na cirurgia apical para melhorar a formação óssea. Aqui é relatado um caso clínico em que a cirurgia apical foi realizada em conjunto com a reconstrução radicular do incisivo lateral superior esquerdo com MTA. Após a cirurgia apical, foi preparada uma retro-cavidade na parede vestibular e o dente envolvido foi obturado com MTA. Um enxerto de osso bovino e uma membrana de colágeno cortical foram colocados no defeito ósseo. Após 5 anos, avaliações clínica e radiográfica mostram que o tratamento foi bem sucedido. Pode-se concluir que o MTA apresenta características favoráveis em condições adversas e que pode ser usado em conjunto com GTR em casos envolvendo reconstrução radicular.

Apical Barrier Formation After Incomplete Orthograde MTA Apical Plug Placement in Teeth with Open Apex - Report of Two Cases

Two cases are reported in which incomplete placement of 4 mm mineral trioxide aggregate (MTA) plug was performed unintentionally at the apical third of permanent immature teeth with open apex and apical periodontitis. As confirmed radiographically, there were gaps between MTA and dentinal walls along the MTA-dentin interface. After setting of MTA was confirmed, endodontic treatment was completed and access was sealed with composite resin. At 6 to 16 months follow-up examinations, formation of dentin in contact with the MTA surface, as well as apical closure and periapical healing were ideied radiographically for both cases. The results of these cases showed that apical barrier formation and complete periapical healing is possible despite the incomplete apical placement of the MTA plug. This might be due to the biological properties of the MTA. Even so, an incomplete three-dimensional placement of the filling material is not advocated.

Reduced incidence and severity of acute radiation mucositis by WF10 (IMMUNOKINE) as adjunct to standard of cure in the management of head & neck cancer patients.

OBJECTIVE: To evaluate the role of WF10-immunotherapy in reducing oro-pharyngeal complications in head and neck cancer chemoradiotherapy. MATERIAL AND METHOD: Thirteen patients were enrolled and assigned either to WF10- (n = 6) or control group (n = 7). After completion of their initial (neoadjuvant) chemotherapy, patients received WF10 intravenous infusions at 0.5 mL/kg body weight/day for five consecutive days and repeated every 3 weeks, concomitantly to standard radiotherapy (6,600-7,500 cGy, 200 cGy/day). Control patients received radiotherapy alone. RESULTS: Patients in the WF10-group had a lower incidence of oro-pharyngeal complications grade > 2, including oral mucositis (1 vs. 5), dysphagia (2 vs. 7), oral pain (3 vs. 5), taste alteration (4 vs. 6) and weight loss (2 vs. 4). The statistical significances were achieved for the parameters of oral mucositis (p = 0. 048) and dysphagia (p = 0.009). CONCLUSION: WF10 appears to reduce severity of oro-pharyngeal complications associated with standard chemoradiotherapy for head and neck cancer.

Absorption and metabolism of paracetamol in rats drinking high concentration of arsenic.

The effect of chronic intake of arsenic on the plasma concentration of paracetamol in rat was investigated. Rats received saline water with or without arsenic trioxide (10 mg/kg body weight/day) by gastric gavage on every alternate day for 29 days. A single dose of paracetamol (range 10 infinity 40 mg/kg body weight) was administered by gastric gavage to both arsenic-untreated and -treated rats on 30(th) day. Rats were sacrificed after 30 min and the amounts of free paracetamol and its metabolites in plasma were estimated using isocratic reverse-phase High Performance Liquid Chromatography (HPLC). Arsenic toxicity reduced the plasma concentration of paracetamol to 53 - 65% when compared with the rats received no added arsenic. There were maximum 67.4 and 76.9% inhibitions of sulfate and cysteine conjugations of paracetamol respectively. But arsenic had no effect on glucuronide and mercapturate conjugations. Both liver and small intestine showed increased accumulation of arsenic and decreased amount of glutathione in arsenic-treated rats. This study suggests that chronic ingestion of arsenic inhibit the absorption and metabolism of paracetamol.

Arsenic trioxide-induced apoptosis is independent of stress-responsive signaling pathways but sensitive to inhibition of inducible nitric oxide synthase in HepG2 cells

Arsenic trioxide (As2O3) has been found to be remarkably effective in the treatment of patients with acute promyelocytic leukemia (APL). Although evidences for the proapoptotic activity of As2O3 have been suggested in leukemic and other solid cancer cells, the nature of intracellular mechanisms is far from clear. In the present study, we investigated As2O3 affect on the stress-responsive signaling pathways and pretreatment with antioxidants using HepG2 cells. When treated with micromolar concentrations of As2O3, HepG2 cells became highly apoptotic paralleled with activation of caspase-3 and members of mitogen-activated protein kinases (MAPKs) including extracellular signal-regulated kinase (ERK) and c-jun NH2-terminal kinase (JNK) but not p38 MAP kinase. However, inhibition of each kinase activity failed to inhibit apoptosis by As2O3. Addition of n-acetyl cysteine (NAC) or diphenyleneiodonium (DPI) effectively protected cells from apoptosis and significantly lowered As2O3-induced activation of caspase-3. However, neither NAC nor DPI was able to effect ERK or JNK activation induced by As2O3. Guanidinoethyldisulfide dihydrochloride (GED) and 2-ethyl- 2-thiopseudourea (ETU), known inhibitors of the inducible nitric oxide synthase (iNOS), also suppressed the apoptotic activity of As2O3. These results suggest that As2O3 induces caspase-mediated apoptosis involving a mechanism generating oxidative stress. However, activation of some stress- responsive signaling pathways by As2O3 may not be the major determinant in the course of apoptotic processes.

Immunotoxicity of soluble and insoluble salts of cadmium instilled intratracheally.

Rats were intratracheally (i.t.) exposed to 36.5 or 27.5 microg of cadmium (Cd) as soluble cadmium chloride (CdCl2) and insoluble cadmium oxide (CdO) salts. The retention of metal in lungs, liver and kidney was assessed by atomic adsorption spectrophotometer. The animals were intraperitoneally (i.p.) primed with sheep red blood cells (SRBC) and assessed for the number of antibody forming cells in lung associated lymph nodes (LALN) and spleen. Both the compounds had similar retention of metal in lungs but CdO induced more pulmonary inflammatory and degradative changes than CdCl2. The larger influx of polymorphonuclear cells (PMNs) following CdO exposure appears to be due to the absence of protection afforded by Cd induced metallothionein cytoplasmic protein while the Cd metallothionein complex formed in the case of CdCl2 is more protective. However both forms of Cd had similar local immunosuppressive potential but CdO had more prolonged suppressive effect.

The efficacy of chemically-stabilized chlorite-matrix (TCDO) in the management of late postradiation cystitis.

Carcinoma of the uterine cervix is the most common cancer of women in Thailand. The most frequent complication after pelvic radiation for uterine cancer is radiation cystitis. The management of severe late postradiation cystis is far from satisfactory. The objective of this study was to evaluate the efficacy of chemically-stabilized chlorite-matrix (TCDO) in patients with severe radiation cystitis. This study was conducted at the Department of Obstetrics and Gynecology, Ramathibodi Hospital and the Department of Radiology, Siriraj Hospital between September 1997 and September 1998. Twenty patients with grade 3 radiation cystitis after radiotherapy were enrolled into this study. TCDO was administered at a dose of 0.5 ml/kg body weight per day on 5 consecutive days as intravenous infusion over 4 hours. The response rate after the first cycle was 80 per cent with 30 per cent of the patients showing complete response. The follow-up time (13 patients) ranging from 1-9 months revealed no recurrent bleeding. There were no side effects from TCDO therapy. The result suggests good efficacy of TCDO in the treatment of postradiation cystitis.