Influência da reinstrumentação do degrau apical radicular após o posicionamento primário do cone principal de guta-percha noselamento apical

The aim of this study was to evaluate in vitro the apical leakage after the apical re-preparation and replacement of the principal gutta-percha point plus endodontic sealer (Sealer 26TM). Sixty extracted human canines were prepared by using a step back technique up to size 50 K type file apically. At each change of instrument the canals were irrigated with distilled water. After that step, the external surface roots were coated and subdivided into six groups with ten roots each: I – single gutta percha point technique; II – lateral condensation and III – hybrid technique. The IV, V and VI groups were similar to others groups but after to place the principal gutta percha point, it was removed, re-prepared up to size 60K file and in sequence replaced the principal gutta percha point and the root canal filling finished. The specimens were immersed in 2% Rhodamine BTM for 7 days at 37 oC. The apical leakage was measured by Image ToolsTM program. With Kruskal Wallis test statistical analysis showed that there was no significant difference between the techniques (p > 0.05).

Avaliação da capacidade de vedamento e pH do tampão apical com cimento Portland branco acrescido de radiopacificadores convencionais

The Portland cement has shown similar biological properties to calcium hydroxide, but its radiopacity is lower. Therefore, the addition of materials that minimize this deficiency should be considered. OBJECTIVE: To evaluate the apical sealing ability and pH of a white Portland cement added of several radiopacifying agents. MATERIAL AND METHODS: Forty bovine roots with incomplete apices were selected, and the foraminal openings were standardized to PM 720G bur. After the external root sealing, an apical intracanal barrier 10.0 mm thick was executed with the white Portland cement powder, pure or added of a radiopacifying agent (iodoform, zinc oxide or bismuth subnitrate), and distilled water (0.37 mL). The apical roots were immersed 24h in water in humid atmosphere, and after that they were immersed 24h in 2% Rhodamine B, under vacuum. In sequence, the roots were longitudinally sectioned, the root fragments were photographed, the images were digitalized and the apical infiltration was measured by the Image Tool program. The pH solutions were also evaluated, in 24h and 48h and 7 and 30 days. Data were submitted to Anova test. RESULTS: The zinc oxide solution has the lowest apical infiltration in relation to the other groups (p < 0.05). The pH behavior varied during the analysis, and in the period of 24h all groups showed the highest values (p < 0.05). CONCLUSION: The type of radiopacifying agent used interferes in the sealing ability of the apical barrier, and zinc oxide showed to be the most beneficial one. The pH varies according to the period of analysis, and the highest values were obtained in the first 24h (p < 0.05).

Conceptos actuales en la preparación de la cavidad apical para obturación retrógrada en cirugía perirradicular

The endodontic surgery is indicated in cases of failure and/or impossibility of conventional endodontic treatment. Among the existent modalities in the endodontic surgery, the retrograde filling consists on preparation of apical cavity and filling with a retrofilling material. The technical-scientific progress in Endodontics become possible the use of retrotips activated with ultrasonic for retrocavities preparation with appropriate extension and following the long axis of the root. The aim of the study was to present the current resources in the preparation of the retrograde cavity in endodontic surgery, detaching their advantages in comparison with the use of conventional preparation with burns. A review of the literature will be presented, considering the use of ultrasound and laser for retrograde preparation, seeking the current resources that provide better apical preparation, resulting in better prognostic of the endodontic surgery (AU)

Influência do diâmetro foraminal do canal radicular, do tipo e da penetração de agulha, e do fluxo da solução irrigadora na limpeza e na extrusão apical

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Clinical Influence of Different Intracanal Medications on Th1-type and Th2-type Cytokine Responses in Apical Periodontitis

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Effect of intracanal dressings on repair and apical bridging of teeth with incomplete root formation

Periapical repair and apical bridging were studied in dog's teeth with incomplete root formation and induced chronic periapical lesions treated with different dressings. A total of 75 root canals from the upper and lower premolars of 4 dogs approximately 6 months of age were chemo-mechanically prepared and filled with the following dressings: antibacterial dressing consisting of a calcium hydroxide+camphorated p-monochlorophenol paste applied for 7 days and followed by monthly renewed calcium hydroxide paste as temporary dressing at 30, 60 and 90 days (Group A); antibacterial dressing consisting of camphorated p-monochlorophenol alone for 7 days, followed by temporary dressing with calcium hydroxide paste renewed at 30, 60 and 90 days (Group B). A control group (Group C) received no dressings. Ninety days after the last calcium hydroxide paste (Groups A, B) and after the last irrigation/aspiration (Group C), the animals were killed, the maxillae and mandibles were removed, and the material submitted to routine histological processing and examination. Both root canal dressings, were of fundamental importance for apical repair and bridging. The apical bridging was predominantly complete in Group A, incomplete in Group B, and absent in Group C. The calcium hydroxide+camphorated p-monochlorophenol combination gave better results than camphorated p-monochlorophenol alone.

Calcium hydroxide root canal sealers - Histopathologic evaluation of apical and periapical repair after endodontic treatment

Eighty root canals of the premolars of 4 dogs, with vital pulp, were instrumented and filled during the same session with the Sealapex, CRCS, Sealer 26, and Apexit sealers, the animals were sacrificed 180 days after root canal filling and their maxillae and mandibles were removed and fixed in 10% formalin, After routine histologic processing, the sections were stained with hematoxylin-eosin and Mallory trichrome, Histopathologic analysis showed that Sealapex was the sealer that best permitted the deposition of mineralized tissue at the apical level and was the only sealer that provided complete sealing (37.5% of cases), With the use of Sealapex, no inflammatory infiltrate occurred and there was no reabsorption of mineralized tissues, In contrast, partial sealing and a moderate inflammatory infiltrate occurred with the use of CRCS, When Apexit and Sealer 26 were used the absence of sealing was frequent and active reabsorption of mineralized tissues occurred in most cases, the inflammatory infiltrate predominating with the use of Apexit was of the severe type, whereas with the use of Sealer 26 the inflammatory infiltrate was mild or absent.

Correlation between volume of apical periodontitis determined by cone-beam computed tomography analysis and endotoxin levels found in primary root canal infection

This clinical study was conducted to correlate the levels of endotoxins and bacterial counts found in primary endodontic infection with the volume of periapical bone destruction determined by cone-beam computed tomography (CBCT) analysis. Moreover, the levels of bacteria and endotoxins were correlated with the development of clinical features. Twenty-four root canals with primary endodontic disease and apical periodontitis were selected. Clinical features such as pain on palpation, pain on percussion, and previous episode of pain were recorded. The volume (cubic millimeters) of periapical bone destruction was determined by CBCT analysis. Endotoxins and bacterial samplings were collected by using sterile/apyrogenic paper points. Endotoxins were quantified by using limulus amebocyte lysate assay (KQCL test), and bacterial count (colony-forming units [CFU]/mL) was determined by using anaerobic culture techniques. Data were analyzed by Pearson correlation and multiple logistic regression (P < .05). Endotoxins and bacteria were detected in 100% of the root canal samples (24 of 24), with median values of 10.92 endotoxin units (EU)/mL (1.75-128 EU/mL) and 7.5 × 10(5) CFU/mL (3.20 × 10(5)-8.16 × 10(6) CFU/mL), respectively. The median volume of bone destruction determined by CBCT analysis was 100 mm(3) (10-450 mm(3)). The multiple regression analysis revealed a positive correlation between higher levels of endotoxins present in root canal infection and larger volume of bone destruction (P < .05). Moreover, higher levels of endotoxins were also correlated with the presence of previous pain (P < .05). Our findings revealed that the levels of endotoxins found in root canal infection are related to the volume of periapical bone destruction determined by CBCT analysis. Moreover, the levels of endotoxin are related to the presence of previous pain.

Avaliação da capacidade seladora apical de um adesivo dentinário, acrescido ou não de hidróxido de cálcio, comparada à de um cimento endodôntico à base de hidróxido de cálcio, na obturação de canais radiculares

Pós-graduação em Odontologia Restauradora - ICT

Efeito dos lasers de Nd:YAG e de Er:YAG na adaptação das obturações de canais radiculares: análise do selamento marginal apical

Pós-graduação em Odontologia Restauradora - ICT

Influence of irrigation and intracanal dressing on the healing process of dogs' teeth with apical periodontitis.

Dogs' teeth with apical periodontitis were treated endodontically, Dakin's solution being used in an experimental group as the irrigation solution, and camphorated paramonochlorophenol as an intracanal dressing. For a second group of teeth, the irrigation solution used was physiologic saline, dry cotton only being placed into the pulpal chamber to take the place of an intracanal dressing. In a second visit, overinstrumentation and a new application of the same kind of dressing were performed, the root canals being then filled with gutta-percha cones and zinc oxide-eugenol cement. Other specimens were treated, in one visit, where physiologic saline or Dakin's solution were the irrigation solutions. The animals were sacrificed 6 months after the obturation of the root canals. Histologic exams showed better results for the experimental group where Dakin's solution and camphorated paramonochlorophenol had been used, with signs of repair characterized by newly formed cementum and bone tissue, as well as a marked reduction in size of the periapical lesions. No differences were seen in the results with physiologic saline or Dakin's solution as irrigants.

Root reconstructed with mineral trioxide aggregate and guided tissue regeneration in apical surgery: a 5-year follow-up

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Changes in phytoplankton composition in response to tides, wind-induced mixing conditions, and freshwater outflows in an urbanised estuarine complex

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Utilization of macrophyte biofilter in effluent from aquaculture: I. Floating plant

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

A scanning electron microscopy study of the seed and post-seminal development in Angelonia salicariifolia Bonpl. (Scrophulariaceae)

The external morphology of seeds and post-germination developmental stages of Angelonia salicariifolia Bonpl. (Scrophulariaceae) were investigated using scanning electron microscopy. Some structural features of the seed exotesta and seedling in Angelonia are presented for the first time and are of potential taxonomic value for this neotropical genus. The seeds are very small (0.9-1.7 mm long and 0.5-0.9 mm wide), ovate, with a reticulate-crested exotesta, reticules arranged uniformly in longitudinal rows, with a high density of microcilia-like projections on the cell wall of the reticule base and on the edge of the crests. The hilum is located beside the micropyle at the narrow end of the seed. Germination is epigeal. During germination the radicle develops, followed by elongation of the hypocotyl and primary root. At this stage dense root hairs develop on the lower part of the hypocotyl. The apical bud-located between the cotyledons-begins to develop after the cotyledons have unfolded. The cotyledons are equal in size, sessile and ovate. The seedlings have two types of trichomes, one characteristic of the cotyledons and first pair of leaves (glandular, sessile, four-celled head with quadrangular shape) and the other characteristic of the hypocotyl and epicotyl (stalked, erect, elongate and three-celled with dome-shaped unicellular head). (C) 2001 Annals of Botany Company.