Effect of ELVAX polymer subgingival implants with echistatin on extracted and reimplanted rats' teeth.

To investigate the effect of ELVAX polymer subgingival implants incorporated with echistatin peptide on incisor reimplanted tooth in rats. Forty-two male Wistars rats were divided into two groups: echistatin-treated rats (E) and control rats (C). The animals had their right maxillary incisors extracted and treated according to the International Association of Dental Traumatology replantation protocol. The extra-alveolar dry period was 30 and 60 min, and the post-surgical experimental periods were 15, 60, and 90 days. The samples were stained with H&E and analyzed for the presence of an inflammatory response, incidence of resorptions, and dental ankylosis. Results were statistically analyzed (p < 0.05). The presence of inflammatory resorption was significantly higher in group C at 30 and 60 min extra-alveolar time, in the 15-day postoperative period as compared with the E group (p < 0.05). Dental ankylosis was significantly more prevalent in group E in 30 min extra-alveolar time and 15 days postoperative period (p < 0.05). However, in 60 min extra-alveolar time and 60 days postoperative period, dental ankylosis was more prevalent in C group (p < 0.05). The use of ELVAX subgingival implants with echistatin demonstrated therapeutic potential in preventing the experimental resorption process after replantation of maxillary incisors in rats.

Analysis of the physicochemical properties, cytotoxicity and volumetric changes of AH Plus, MTA Fillapex and TotalFill BC Sealer.

BACKGROUND: To evaluate the physicochemical properties and cytotoxicity of AH Plus, MTA Fillapex and TotalFill BC Sealer. Volumetric changes were also evaluating using micro-computed tomography (micro-CT). MATERIAL AND METHODS: Radiopacity and flow were evaluated in accordance with the ISO 6876, while setting time was evaluated in accordance with the ASTM- C266-08 specifications. The release of Ca2+ ions and pH were measured with spectrophotometer and pH meter, respectively, after different time intervals (1h, 3h, 24h, 72h, 168h, and 360h). Cytotoxicity was evaluated by MTT reduction assay to check 3T3 cells viability at 24, 48 and 72 hours. Volumetric change was evaluated by micro-CT, by using 30 acrylic teeth, filled with gutta-percha cones and the tested root canal sealer. The samples were evaluated after 168h, 360h and 720h of immersion in distilled water. Data were statistically analyzed by one-way ANOVA and Tukey test or by Kruskal-Wallis and Dunn tests (P<0.05). RESULTS: MTA Fillapex and TotalFill BC Sealer showed lower radiopacity than AH Plus (P<0.05). The MTA Fillapex showed the highest flow, while AH Plus showed the lowest flow (P<0.05). The initial and final setting time of AH Plus were lower than MTA Fillapex and TotalFill BC Sealer (P<0.05). In general, TotalFill BC Sealer presented higher Ca2+ ion release and pH than the other tested sealers. TotalFill BC Sealer also showed overall lower cytotoxicity when compared to the other sealers. Volumetric change of AH Plus and TotalFill BC Sealer was lower than MTA Fillapex (P<0.05). CONCLUSIONS: AH Plus, MTA Fillapex and TotalFill BC Sealer showed slight differences in the physicochemical properties and cytotoxicity, but all suitable for an endodontic sealer. However, AH Plus and TotalFill BC Sealer showed low volumetric changes when compared to MTA Fillapex. Key words:Calcium silicate, cytotoxicity, physicochemical properties, micro computed tomography.

Tratamento não cirúrgico para remoção de instrumento fraturado e guta-percha extravasada, com o uso do Masserann EndoKit / Non-surgical treatment for removing fractured instrument and extravasated gutta-percha, by using the Masserann EndoKit

Objetivo: o objetivo deste artigo é relatar um caso clínico em que um instrumento fraturado e a guta-percha extravasada foram removidos via canal. Relato de caso: paciente do sexo masculino, com 38 anos de idade, foi encaminhado para avaliação do incisivo lateral superior direito (dente #12). O paciente apresentava dor à palpação na região apical e ausência de sintomatologia espontânea. O exame radiográfico revelou a presença de cone de guta-percha extravasado, uma espiral de Lentulo fraturada, além de lesão periapical no dente #12. O retratamento endodôntico foi o procedimento de escolha, na tentativa de remover os dois materiais. A espiral de Lentulo foi removida com Masserann Endokit; e o cone de guta-percha, utilizando limas Hedstroen. Após realizar a instrumentação e o preenchimento do conduto com pasta de hidróxido de cálcio com iodofórmio, constatou- se a presença de reabsorção no terço apical. Depois de dois meses, observou-se redução da lesão; utilizou-se, então, MTA na região da reabsorção, e o conduto foi obturado com cone de guta-percha e cimento endodôntico Sealer 26. Conclusão: controles clínicos e radiográficos foram realizados após dois, quatro e oito anos, demonstrando reparo na região apical e ausência de sintomatologia (AU).

The objective of this article was to report a clinical case of finding a fractured instrument and over-extended guttapercha of a tooth, which were removed via the canal. The patient, a 38-year-old man, was referred for treatment of the right maxillary lateral incisor (tooth 7). The patient presented pain on palpation at the apical level and absence of spontaneous symptomatology. Radiographic examination revealed the presence of a over-extended gutta-percha cone, a fractured Lentulo spiral and periapical lesion in tooth 7. Endodontic retreatment was the chosen procedure in an attempt to remove both materials. The Lentulo spiral was removed by means of the Masserann Endokit, and the gutta-percha cone by using Hedstroen files. While performing instrumentation, and filling the canal with calcium hydroxide with iodoform, the presence of resorption in the apical third was verified. After 2 months, reduction of the lesion was observed, thus MTA was placed in the area of resorption and the remainder of the canal was filled with a gutta-percha cone and Sealer 26 cement. Clinical and radiographic controls performed after 2, 5 and 7 years showed repair of the area and absence of symptomatology (AU).

CAMPANELLIProgrammed Death 1 (PD-1) and PD-1 Ligand (PD-L1) Expression in Chronic Apical Periodontitis.

OBJECTIVE: This study aimed to examine programmed death protein 1 (PD-1) and programmed death lig-and 1 (PD-L1) expression on leukocytes from chronic apical periodontitis, and to determine the levels of cytokines in the apical periodontitis lesions. METHODS: Leukocytes from healthy gingival tissue (n=16) and chronic apical periodontitis (n=10) were eval-uated using flow cytometry. The PD-1 and PDL-1 expressions were evaluated using flow cytometry. The cy-tokine levels were evaluated by enzyme-linked immunosorbent assay. Data were analyzed using one-way ANOVA. The statistical significance level was set at P<0.05. RESULTS: Results showed that the apical periodontitis lesions are more infiltrated by PD-1+ and PDL1+ lym-phocytes than the control samples. In addition, the PDL-1 expression was detected on macrophages in the apical periodontitis lesions, and was significantly higher compared to leukocytes from healthy gingival tis-sue. The IFN-γ, TGF-ß, IL-10, and TNF-α levels were significantly higher in the apical periodontitis lesions com-pared to control samples. CONCLUSION: The PD-1, PD-L1, and CTLA-4 molecules are evident in apical periodontitis, and can be an impor-tant immune checkpoint in chronic periapical periodontitis.

Comparison of two methods of irrigant agitation in the removal of residual filling material in retreatment.

The aim of this study was to compare the efficacy of passive ultrasonic irrigation and EasyClean for removing residual filling material in retreatment. Twenty-two maxillary lateral incisors with apical curvature were instrumented with ProTaper files and filled with Endofill using the lateral compactation technique. Removal of filling material was performed with Reciproc, Mtwo and ProDesign Logic 50/.01 files. The teeth were inserted in a silicone mould, which was placed in a metal muffle, and split to visualize the residual filling material. The samples were divided into two groups (n = 11) according to the irrigation protocol: Passive ultrasonic irrigation (PUI group) with 3 activations of 20 seconds and EasyClean (Easy Equipamentos Odontológicos, Belo Horizonte, Brazil) (EC group) used in continuous rotation with 3 activations of 20 seconds, both using NaOCl and EDTA. Environmental scanning electron microscopic images of the apical, middle, and cervical thirds were taken before and after the irrigant activation. The Kappa test was used to determine interexaminer agreement. Statistical analysis was performed using Kruskal-Wallis, Mann-Whitney, and Wilcoxon tests (p < 0.05). PUI and EC improved the removal of remnant filling material in all root canal thirds (p < 0.05). PUI and EC presented similar performance in the final step of retreatment (p > 0.05). No significant difference was observed in the removal of filling material in the apical, middle, and cervical thirds in both groups (p > 0.05). EasyClean in continuous rotary motion is useful in retreatment and was shown to be as effective as ultrasonic activation in the removal of remnant filling material.

Prevalence and morphometric analysis of three-rooted mandibular first molars in a Brazilian subpopulation.

OBJECTIVES:: To determine the prevalence of three-rooted mandibular molars in a Brazilian population using cone beam computed tomography (CBCT) and to analyze the anatomy of mandibular first molars with three roots through micro-CT. MATERIAL AND METHODS:: CBCT images of 116 patients were reviewed to determine the prevalence of three-rooted first mandibular molars in a Brazilian subpopulation. Furthermore, with the use of micro-CT, 55 extracted three-rooted mandibular first molars were scanned and reconstructed to assess root length, distance between canal orifices, apical diameter, Vertucci's classification, presence of apical delta, number of foramina and furcations, lateral and accessory canals. The distance between the orifice on the pulp chamber floor and the beginning of the curvature and the angle of canal curvature were analyzed in the distolingual root. Data were compared using the Kruskal-Wallis test (α=0.05). RESULTS:: The prevalence of three-rooted mandibular first molars was of 2.58%. Mesial roots showed complex distribution of the root canal system in comparison to the distal roots. The median of major diameters of mesiobuccal, mesiolingual and single mesial canals were: 0.34, 0.41 and 0.60 mm, respectively. The higher values of major diameters were found in the distobuccal canals (0.56 mm) and the lower diameters in the distolingual canals (0.29 mm). The lowest orifice distance was found between the mesial canals (MB-ML) and the highest distance between the distal root canals (DB-DL). Almost all distal roots had one root canal and one apical foramen with few accessory canals. CONCLUSIONS:: Distolingual root generally has short length, severe curvature and a single root canal with low apical diameter.

Prevalence and morphometric analysis of three-rooted mandibular first molars in a Brazilian subpopulation

ABSTRACT The knowledge of the internal anatomy of three-rooted mandibular molars may help clinicians to diagnose and plan the root canal treatment in order to provide adequate therapy when this variation is present. Objectives: To determine the prevalence of three-rooted mandibular molars in a Brazilian population using cone beam computed tomography (CBCT) and to analyze the anatomy of mandibular first molars with three roots through micro-CT. Material and Methods: CBCT images of 116 patients were reviewed to determine the prevalence of three-rooted first mandibular molars in a Brazilian subpopulation. Furthermore, with the use of micro-CT, 55 extracted three-rooted mandibular first molars were scanned and reconstructed to assess root length, distance between canal orifices, apical diameter, Vertucci's classification, presence of apical delta, number of foramina and furcations, lateral and accessory canals. The distance between the orifice on the pulp chamber floor and the beginning of the curvature and the angle of canal curvature were analyzed in the distolingual root. Data were compared using the Kruskal-Wallis test (α=0.05). Results: The prevalence of three-rooted mandibular first molars was of 2.58%. Mesial roots showed complex distribution of the root canal system in comparison to the distal roots. The median of major diameters of mesiobuccal, mesiolingual and single mesial canals were: 0.34, 0.41 and 0.60 mm, respectively. The higher values of major diameters were found in the distobuccal canals (0.56 mm) and the lower diameters in the distolingual canals (0.29 mm). The lowest orifice distance was found between the mesial canals (MB-ML) and the highest distance between the distal root canals (DB-DL). Almost all distal roots had one root canal and one apical foramen with few accessory canals. Conclusions: Distolingual root generally has short length, severe curvature and a single root canal with low apical diameter.

Efficacy of CM-Wire, M-Wire, and Nickel-Titanium Instruments for Removing Filling Material from Curved Root Canals: A Micro-Computed Tomography Study.

INTRODUCTION: The aim of this ex vivo study was to evaluate the removal of filling material after using CM-wire, M-wire, and nickel-titanium instruments in both reciprocating and rotary motions in curved canals. METHODS: Thirty maxillary lateral incisors were divided into 9 groups according to retreatment procedures: Reciproc R25 followed by Mtwo 40/.04 and ProDesign Logic 50/.01 files; ProDesign R 25/.06 followed by ProDesign Logic 40/.05 and ProDesign Logic 50/.01 files; and Gates-Glidden drills, Hedström files, and K-files up to apical size 30 followed by K-file 40 and K-file 50 up to the working length. Micro-computed tomography scans were performed before and after each reinstrumentation procedure to evaluate root canal filling removal. Statistical analysis was performed with Kruskal-Wallis, Friedman, and Wilcoxon tests (P < .05). RESULTS: No significant differences in filling material removal were found in the 3 groups of teeth. The use of Mtwo and ProDesign Logic 40/.05 rotary files did not enhance filling material removal after the use of reciprocating files. The use of ProDesign Logic 50/.01 files significantly reduced the amount of filling material at the apical levels compared with the use of reciprocating files. CONCLUSIONS: Association of reciprocating and rotary files was capable of removing a large amount of filling material in the retreatment of curved canals, irrespective of the type of alloy of the instruments. The use of a ProDesign Logic 50/.01 file for apical preparation significantly reduced the amount of remnant material in the apical portion when compared with reciprocating instruments.

Avaliação em microCT do preparo dos canais mesiais de molares inferiores realizado por dois sistemas rotatórios de NiTi / Micro-CT evaluation of mesial canals preparation performed by two rotary NiTi systems in mandibular molars

Objetivo: avaliar em microCT a qualidade do preparo e desgaste das paredes mesiais e de furca de molares inferiores. Métodos: trinta molares inferiores humanos foram extraídos e escaneados em microCT. Os parâmetros analisados foram: centralização do canal radicular, extensão e direção do desvio na instrumentação, quantidade de dentina removida, espessura mínima de remanescente e os volumes apical e total antes e após instrumentação. Os dentes foram divididos em 3 grupos (n = 10): Grupo 1 = instrumentação com ProTaper até o instrumento F2; Grupo 2 = Twisted File, instrumento 25/08; Grupo 3 = instrumentação manual (controle). Resultados: não houve diferença significativa (p > 0,05) entre os sistemas rotatórios, em relação ao desvio na instrumentação, em todos os níveis analisados. O terço cervical apresentou maior quantidade de desvio na instrumentação quando comparado ao nível apical, e menor quantidade de remanescente, especialmente na zona de furca. Os sistemas removeram maior quantidade de dentina das paredes de furca (terço médio e cervical). Não houve diferença entre os grupos em relação à quantidade de dentina no terço apical. Os volumes apical e total não aumentaram significativamente após o preparo com os instrumentos rotatórios. Conclusão: os sistemas rotatórios de NiTi avaliados não aumentaram significativamente os volumes apical e total dos canais radiculares. O maior desvio na instrumentação ocorreu nos terços médio e cervical para todos os sistemas analisados. Para todos os grupos analisados, a quantidade de remanescente foi significativamente reduzida na direção da furca dos terços médio e cervical.

Sealing ability of MTA, CPM, and MBPc as root-end filling materials: a bacterial leakage study.

Objectives To evaluate the sealing ability of three root-end filling materials (white MTA, CPM, and MBPc) using an Enterococcus faecalis leakage model. Material and Methods Seventy single-root extracted human teeth were instrumented and root-ends were resected to prepare 3 mm depth cavities. Root-end preparations were filled with white MTA, CPM, and MBPc cements. Enterococcus faecalis was coronally introduced and the apical portion was immersed in BHI culture medium with phenol red indicator. The bacterial leakage was monitored every 24 h for 4 weeks. The statistical analysis was performed using the Wilcoxon-Gehan test (p<0.05). Results All cements showed bacterial leakage after 24 hours, except for the negative control group. The MBPc showed significantly less bacterial leakage compared with the MTA group (p<0.05). No significant differences were found between the CPM and the other groups. Conclusions The epoxy resin-based cement MBPc had lower bacterial leakage compared with the calcium silicate-based cements MTA and CPM.