Comparative Evaluation of Efficacy of Three Single File Retreatment Systems for Removal of Gutta Percha and Assessment of Root Canal Transportation - An In Vitro Study

Background: In comparison to multiple file systems, recent advancements in single file retreatment systems had reduced the working time and ease of operation for clinicians. Aim: To compare the efficacy of retreatment systems compared with hand instrumentation, by evaluating their removal efficacy, time required for retreatment and assessment of canal transportation. Methods and Material: Forty premolars were instrumented using ProTaper Gold gold files. Post instrumentation, scan was taken, obturated using warm vertical compaction technique, and stored in artificial saliva for three months and randomly divided into four groups for retreatment. Hand instrumentation (Hi), Neoniti (Nn), Mtwo R (Mt), WaveOne Gold (Wg). Post retreatment, scan was taken. Teeth were sectioned longitudinally and photographed under the stereomicroscope. Retreatment time was recorded, and canal transportation was calculated. Statistical Analysis: The results were analyzed using one?way analysis of variance (ANOVA) followed by Tukey’s post hoc test at 95% confidence level. Results: The retreatment time was significantly longer in the Hi group. Within the test groups, a significantly longer time has been taken by Wg (p < 0.05) compared to Mt and Nn. There was no difference in the canal transportation between the single file systems at 3 mm, 6 mm and 9 mm from the apex, there was statistically significant higher transportation for the Hi group at 9 mm from the apex (p < 0.05). Conclusions: All techniques were effective in removal of filling material with minimal canal transportation. Wg system was shown to increased time compared to Nn and Mt systems. Hi group was slowest with maximum canal transportation at 9 mm from the apex.

Disinfection and outcome of root canal treatment using single-file or multifile systems and Ca(OH)2 medication

Abstract This clinical study reports on the antibacterial effects and outcome of endodontic treatment using either a single-file or a multifile system, associated with calcium hydroxide interappointment medication. The root canals of single-rooted teeth with apical periodontitis were treated by using either Reciproc or BioRaCe instrument systems, 2.5% NaOCl irrigation, and calcium hydroxide medication. Bacteriological samples taken before preparation and immediately before obturation were evaluated for total bacterial counts by quantitative real-time polymerase chain reaction (qPCR). Patients were followed up and the treatment outcome was assessed by clinical and radiographic criteria. Decreasing lesions were classified as success in a lenient criterion or failure in a rigid one. Bacteria were detected in all initial samples (47 cases) and were significantly reduced after treatment in both groups (p<0.001). In the Reciproc and BioRaCe groups, 7/25 (28%) and 11/22 (50%) root canals yielded negative qPCR results before obturation, respectively (p>0.05). Quantitative bacterial reduction was similar between groups (p>0.05). The success rate in the BioRaCe group was 95.5% and 77% in the loose and rigid criterion, respectively. In the Reciproc group, corresponding figures were 88% and 76%. Differences in outcome were not significant (p>0.05). No diseased case showed negative qPCR results for bacteria. A difference of >1 Log10 counts was observed between healed and diseased cases. Root canal treatments of teeth with apical periodontitis using a single-file or a multifile system for preparation, associated with NaOCl irrigation and calcium hydroxide interappointment medication, showed similar antibacterial effectiveness and success rate.

Resumo Este estudo clínico relata os efeitos antibacterianos e o resultado de tratamentos endodônticos usando um sistema de instrumentação de instrumento único ou de múltiplos instrumentos, associado à medicação intracanal com hidróxido de cálcio. Os canais radiculares de 80 dentes unirradiculares com lesão perirradicular foram tratados com os sistemas Reciproc ou BioRaCe, irrigação com NaOCl a 2,5% e medicação com pasta de hidróxido de cálcio por 7 a 10 dias. Amostras bacteriológicas foram colhidas antes do preparo e imediatamente antes da obturação e examinadas quanto à contagem total de bactérias pela reação em cadeia da polimerase em tempo real quantitativa (qPCR). Os pacientes foram acompanhados e o resultado do tratamento foi avaliado por critérios clínicos e radiográficos (índice periapical). Os casos com lesões que diminuíram mas não desapareceram foram classificados como sucesso em um critério leniente ou fracasso em um critério rígido. Quarenta e sete pacientes estavam disponíveis para avaliação bacteriológica e de resultados. Bactérias foram detectadas em todas as amostras iniciais desses casos e foram significativamente reduzidas após o tratamento nos dois grupos (p<0,001). Nos grupos Reciproc e BioRaCe, os canais radiculares apresentaram resultados negativos na qPCR em 7/25 (28%) e 11/22 (50%) casos antes da obturação, respectivamente (p>0,05). A redução bacteriana foi semelhante entre os grupos (p>0,05). O período médio (mediana) de acompanhamento foi de 20,5 (18,5) meses para BioRaCe e 17,4 (18) meses para Reciproc (p>0,05). No grupo BioRaCe, a taxa de sucesso foi de 95,5% e 77% nos critérios leniente e rígido, respectivamente. No grupo Reciproc, os valores correspondentes foram 88% e 76%. As diferenças no resultado não foram estatisticamente significativas (p>0,05). Nenhum caso de doença pós-tratamento mostrou resultados negativos de qPCR para bactérias. Foi observada uma diferença >1 Log10 nas contagens bacterianas entre os casos curados e doentes. O tratamento do canal radicular de dentes com lesão perirradicular utilizando um sistema de instrumento único ou múltiplos no preparo, associado à irrigação com NaOCl e medicação entre consultas com hidróxido de cálcio, mostrou eficácia antibacteriana e taxa de sucesso semelhantes.

Assessment of the Performance and Surface Alteration of Two Single-file Systems According to the Number of Uses

Abstract The aim of this study was to assess the performance and surface alteration of two single-file systems according to the number of uses. Ten WaveOne Primary files (25/.08) and ten One Shape NG files (25/.06) were used for instrumentation of mesial root canals of mandibular molars. Each instrument was cleaned and sterilized after the preparation of two root canals and then reused. The time spent for instrumentation of each root canal was recorded and analyzed by using t-test. Microphotographs of the surface of the instruments were taken with a scanning electron microscope at different magnifications (i.e. 18x, 160x, 500x and 1000x) and at a distance of 4 mm from the instrument's tip before being analyzed by four observers. Presence of disruption of cutting edge, crack, craters and unwinding was assessed and submitted to Fisher's exact test. Both systems showed manufacturing defects and cracks. The presence of disruption of cutting edges was major in WaveOne files from the sixth use, whereas One Shape NG files showed more unwinding. Only preparation time using WaveOne files was influenced by the number of uses. One can conclude that WaveOne files had more disruption of cutting edges and took longer time for root canal preparation from the sixth use onwards, whereas the One Shape NG files showed more unwinding at the tenth use.

Apically extruded debris in filling removal of curved canals using 3 NiTi systems and hand files

Abstract The aim of this study was to assess the amount of apically extruded debris during filling removal with WaveOne Gold (WOG), ProTaper Universal Retreatment (PTR), D-RaCe Retreatment (DRR) or hand files (HF), to compare the working time during filling removal, and to describe failures of NiTi instruments. Forty mesiobuccal roots of maxillary first molars were prepared with WOG Primary, obturated and divided into 4 groups (n=10), according to the instruments used: WOG, PTR, DRR or HF. Distilled water was used as irrigant and the extruded debris were collected in Eppendorf tubes and dried. The amount of extruded debris was determined by subtracting the final from the initial weight. The time of filling removal for each canal was recorded and the instruments used were analyzed pre and post-operatively by SEM. Kruskal-Wallis and Dunn's test analyzed extruded debris data and ANOVA, followed by Tukey's test, compared the working time data (a=0.05). Instrument deformation and fracture were described. WOG produced significantly less debris compared with HF and DRR (p<0.05), and similar to PTR (p>0.05). HF, PTR and DRR showed no significant difference (p>0.05). Working time in HF group was significantly higher than others (p<0.05). SEM analyses showed, from the 18 instruments evaluated, 3 fractures and 10 deformations. All instruments tested caused debris extrusion. WOG was associated with less extrusion than DRR and HF. Filling removal with HF was slower than with the other instruments. All NiTi systems presented fracture and deformation.

Resumo O objetivo deste estudo foi avaliar a extrusão apical de debris durante a desobturação com WaveOne Gold (WOG), ProTaper Universal Retratamento (PTR), D-RaCe (DRR) ou limas manuais (HF), comparar o tempo de trabalho durante a desobturação, e descrever as falhas dos instrumentos de NiTi. Quarenta canais de raízes mésio-vestibulares de primeiros molars superiores foram preparados com WOG Primary, obturados e divididos em 4 grupos (n = 10), de acordo com os instrumentos a serem utilizados: WOG, PTR, DRR ou HF. Água destilada foi utilizada como irrigante, e os debris extruídos foram coletados em tubos Eppendorf e secos. A quantidade de debris extruídos foi determinada subtraindo-se o peso inicial do peso final. O tempo de cada desobturação foi anotado e os instrumentos utilizados foram analisados no pré e pós-operatório em MEV. Os testes Kruskal-Wallis e Dunn foram utilizados para analisar os dados da extrusão de debris, e os testes ANOVA e Tukey para comparar os dados do tempo de trabalho (a=0.05). As deformações e fraturas dos instrumentos foram descritas. O grupo WOG produziu significativamente menos debris quando comparado aos grupos HF e DRR (p<0.05), e foi similar ao grupo PTR (p>0.05). Os grupos HF, PTR e DRR não apresentaram diferença estatisticamente significante (p>0.05). O tempo de trabalho no grupo HF foi significativamente maior do que nos outros grupos (p<0.05). A análise em MEV mostrou que, dos 18 instrumentos avaliados, 3 fraturaram e em 10 foi observado deformação. Todos os sistemas testados causaram extrusão apical de debris. WOG foi associado com menor extrusão do que DRR e HF. A desobturação com HF foi mais lenta do que com os demais instrumentos. Todos os sistemas de NITI apresentaram fratura e deformação.

WaveOne Gold, un nuevo instrumento reciprocante para la conformación de los conductos radiculares / WaveOne Gold, a new reciprocating instrument for root canal shaping

El objetivo del presente artículo es describir y analizar el nuevo sistema de limas reciprocantes WaveOne Gold, evolución del sistema WaveOne presentado en 2010. Las mejoras en su diseño y en su metalurgia les otorgan más flexibilidad y aumentan su resistencia a la fatiga cíclica, lo cual brinda al clínico la posibilidad de instrumentar con más seguridad y confianza el sistema de conductos radiculares.

The aim of the present article is to describe and analyzethe new reciprocating system WaveOne Gold.This instrument, preceded by the WaveOne in 2010, showsimprovements in its design and in its metallurgy, providingmore flexibility and increasing its resistance to cyclic fatigue.Alfie D, García G, Rodríguez P. WaveOne Gold, un nuevo instrumento reciprocante para la conformaciónde los conductos radiculares. Rev Asoc Odontol Argent 2016;105:78-82.This gives the clinician greater security and confidence duringthe shaping of the root canal system.

A comparison of the shaping ability of reciprocating NiTi instruments in simulated curved canals

OBJECTIVES: The study was to compare the shaping ability of Reciproc (VDW) and WaveOne (Dentsply Maillefer) instruments compared with ProTaper, Profile and hand instrument during the preparation of simulated root canals. MATERIALS AND METHODS: Five groups (n = 5) were established. Reciproc, WaveOne, ProTaper, Profile and K file (K-flexo file) were used to prepare the resin simulated canals. A series of preoperative and postoperative images were taken by a microscope and superimposed in 2 different layers. The amount of resin removed from both the inner and the outer sides of the canal was measured to the level of 10 mm from the apical tip, with a 1 mm increment. RESULTS: The mean of resin removal from the inner canal wall was not different from the outer canal wall for Reciproc and WaveOne groups at apical third (1 - 3 mm level). There was no difference in the change of working length and maintenance of canal curvature. NiTi instruments are superior to stainless-steel K file in their shaping ability. CONCLUSIONS: Within the limitation of this present study, Reciproc and WaveOne instruments maintained the original canal curvature in curved canals better than ProTaper and Profile, which tend to transport towards the outer canal wall of the curve in the apical part of the canal.