Effects of the Irrigation Needle Design on Root Canal Disinfection and Cleaning.

INTRODUCTION: This ex vivo study evaluated the disinfecting and cleaning effects of root canal preparation using sodium hypochlorite irrigation with 3 different needle designs. METHODS: Mesial roots from extracted mandibular molars with Vertucci class II configuration were anatomically matched based on micro-computed tomography (micro-CT) analyses and distributed into 3 groups (n = 18/group). The canals were contaminated with a mixed bacterial culture for 30 days and then subjected to preparation using 2.5% sodium hypochlorite irrigation with open-ended flat needle (3 mm short of the working length - WL), closed-ended side-vented irrigation needle (1 mm short of the WL), or a closed-ended plastic needle with 2 lateral outlets (TruNatomy) (1 mm short of the WL). Bacteriological samples were taken from the canals before (S1) and after preparation (S2). After another micro-CT scan, the roots were sectioned and samples were also taken from the apical canal segment (S3). Bacterial reduction was assessed by quantitative real-time polymerase chain reaction. The amount of accumulated hard tissue debris was evaluated by micro-CT. RESULTS: A substantial reduction in bacterial counts was observed in all 3 groups when comparing S1 with S2 (99.95%, 98.93%, and 98.90% in the open-ended, closed-ended, and TruNatomy needle groups, respectively) (P < .01). No significant differences were observed between groups for bacterial reduction in the full and apical canal (P > .05). There were no intergroup differences in the amount of accumulated hard tissue debris either (P > .05). The open-ended needle group showed significantly more specimens with quantitative real-time polymerase chain reaction negative results for bacteria in S3 than TruNatomy (P < .05). CONCLUSION: When used up to an appropriate insertion depth, the 3 needle types result in similar antibacterial and cleaning performance, provided variables such as needle size and irrigant type, volume and flow rate are controlled. Exclusive analysis of the apical segment, including the isthmus, revealed that the open-ended needle yielded more cases negative for bacteria.

Bacteriologic Conditions of the Apical Root Canal System of Teeth with and without Posttreatment Apical Periodontitis: A Correlative Multianalytical Approach.

INTRODUCTION: This study used a correlative multianalytical approach to investigate the bacteriologic conditions in the apical root canal system of treated teeth with or without apical periodontitis and their correlation with the technical quality of the previous root canal obturation and the presence and volume of apical periodontitis lesions. METHODS: Root apexes were obtained from recently extracted root canal-treated teeth with (n = 23) and without (n = 22) apical periodontitis lesions as demonstrated by cone-beam computed tomographic examination. The root apexes were sectioned and subjected to micro-computed tomographic (micro-CT) scanning. The specimens were cryopulverized, and DNA extracted from the powder was used as a template in real-time polymerase chain reaction assays to quantify total bacteria and members of the Streptococcus genus and Actinobacteria phylum. The bacteriologic findings were compared between the 2 groups and also evaluated for associations with cone-beam computed tomographic and micro-computed tomographic data. RESULTS: Bacteria were detected in all apical canal samples except 1. The mean counts of total bacteria, streptococci, and actinobacteria did not differ significantly between teeth with or without apical periodontitis (P > .05). Streptococcus levels were significantly lower by 80% in the apical canals of teeth with small lesions compared with those without lesions (P < .05). The limit of filling >2 mm short was significantly associated with more total bacterial counts compared with canals filled 0-2 mm short (P < .05). An adequate coronal restoration was significantly associated with lesser counts of Streptococcus (P < .05). CONCLUSIONS: Comparable bacterial loads were observed in the apical canal system of treated teeth with and without apical periodontitis, suggesting that factors other than only the total bacterial levels may also influence the development and progression of apical periodontitis. Bacteria were found in the apical canal in virtually all cases with a high prevalence of streptococci and actinobacteria. Streptococci counts were significantly higher in the apical canal of teeth with inadequate restorations and teeth with no lesions. Underfilled canals showed higher bacterial counts.

Unvaccinated periodontal patients with a history of COVID-19: clinical findings in a Dental School setting.

This study analyzed the periodontal clinical data of individuals with a history of COVID-19 treated in a dental school during the pandemic in 2021 before vaccination. METHODS: This analysis included individuals older than 18 years with no history of systemic disorders other than systemic arterial hypertension. Individuals who had COVID-19 were classified according to the World Health Organization as asymptomatic, with mild, moderate, severe, or critical symptoms. RESULTS: A total of 95 individuals were evaluated, which included 24 with a history of COVID-19. Seventeen percent had been asymptomatic, 21% had mild, 25% moderate, 21% severe, and 17% critical symptoms, including intubation. Individuals with no history of COVID-19 presented significantly lower measurements of probing depth (p=0.003; Mann-Whitney test) and clinical attachment level (p=0.002) compared to individuals with a history of COVID-19. A significant negative association was found between bleeding on probing and the severity of characteristics of COVID-19 (rho= -0.233; p=0.023). Conversely, positive associations between the values of probing depth (rho= 0.292; p=0.004) and mean clinical attachment level (rho= 0.300; p=0.003) and the characteristics of COVID-19 were found. CONCLUSIONS: The periodontal data shows that patients who had COVID-19 before vaccination may present a worse periodontal status when compared to patients in the same clinical setting with no history of COVID-19. However, a more extensive study should confirm it with more participants.

Influence of sealer type on treatment outcome of teeth with apical periodontitis: a systematic review.

BACKGROUND: The purpose of this article was to Evaluate the influence of sealer on the outcome of non-surgical endodontic treatment or retreatment of permanent teeth with apical periodontitis (PROSPERO registration: CRD42020205951). METHODOLOGY: A systematic review of original clinical studies was carried out following PRISMA guidelines to answer whether the type of sealer used in endodontic treatment or retreatment influences the repair of apical periodontitis determined by clinical and radiographic parameters. Electronic searches were performed in PubMed, Embase, Web of Science, Scopus, and the Cochrane Library database, until May 2023. Gray literature and a hand search of reference lists were also performed. The risk of bias was assessed using Cochrane RoB2 for randomized trials and the Newcastle-Ottawa Scale (NOS) for prospective and retrospective cohort and case-control studies. RESULTS: Among 1046 studies, a total of 819 were selected by title and abstract, resulting in 23 for full-text review. In total, 11 studies met the inclusion criteria (1467 patients/teeth with apical periodontitis). The quality assessment using RoB2 included five randomized control trials, of which four had medium risk and one had a low risk of bias. According to the NOS scale, five studies were classified as low risk and one study was considered as medium risk of bias. The sealer type and obturation techniques varied, and the mean follow-up time was 3.7 years. Most studies used two-dimensional radiographic criteria to assess the treatment outcome sealers and not cements. Eight studies did not find significant differences when comparing cements. The healing rates ranged from 56.7% to 90%. CONCLUSIONS: The results of this review support that the current endodontic sealers do not seem to influence the treatment outcome of permanent teeth with apical periodontitis. Although the studies had medium and low risk of bias, the results should be interpreted with caution. More randomized studies of long-term outcomes comparing filling materials are needed to strengthen this claim and allow for a meta-analysis.

Unvaccinated periodontal patients with a history of COVID-19: clinical findings in a Dental School setting

Abstract This study analyzed the periodontal clinical data of individuals with a history of COVID-19 treated in a dental school during the pandemic in 2021 before vaccination. Methods: This analysis included individuals older than 18 years with no history of systemic disorders other than systemic arterial hypertension. Individuals who had COVID-19 were classified according to the World Health Organization as asymptomatic, with mild, moderate, severe, or critical symptoms. Results: A total of 95 individuals were evaluated, which included 24 with a history of COVID-19. Seventeen percent had been asymptomatic, 21% had mild, 25% moderate, 21% severe, and 17% critical symptoms, including intubation. Individuals with no history of COVID-19 presented significantly lower measurements of probing depth (p=0.003; Mann-Whitney test) and clinical attachment level (p=0.002) compared to individuals with a history of COVID-19. A significant negative association was found between bleeding on probing and the severity of characteristics of COVID-19 (rho= -0.233; p=0.023). Conversely, positive associations between the values of probing depth (rho= 0.292; p=0.004) and mean clinical attachment level (rho= 0.300; p=0.003) and the characteristics of COVID-19 were found. Conclusions: The periodontal data shows that patients who had COVID-19 before vaccination may present a worse periodontal status when compared to patients in the same clinical setting with no history of COVID-19. However, a more extensive study should confirm it with more participants.

Resumo Este estudo analisou os dados clínicos periodontais de indivíduos com histórico de COVID-19 tratados em uma escola de odontologia durante a pandemia em 2021, antes da vacinação. Métodos: Essa análise incluiu indivíduos maiores de 18 anos sem histórico de distúrbios sistêmicos, exceto hipertensão arterial sistêmica. Os indivíduos que tiveram COVID-19 foram classificados de acordo com a Organização Mundial da Saúde como assintomáticos, com sintomas leves, moderados, graves ou críticos. Resultados: 95 indivíduos foram avaliados, incluindo 24 com histórico de COVID-19. 17% eram assintomáticos, 21% tinham sintomas leves, 25% moderados, 21% graves e 17% críticos, incluindo intubação. Os indivíduos sem histórico de COVID-19 apresentaram medidas significativamente mais baixas de profundidade de sondagem (p=0,003; teste de Mann-Whitney) e nível de fixação clínica (p=0,002) em comparação com indivíduos com histórico de COVID-19. Foi encontrada uma associação negativa significativa entre o sangramento à sondagem e a gravidade das características da COVID-19 (rho= -0,233; p=0,023). Por outro lado, foram encontradas associações positivas entre os valores de profundidade de sondagem (rho = 0,292; p = 0,004) e o nível médio de apego clínico (rho = 0,300; p = 0,003) e as características da COVID-19. Conclusão: Os dados periodontais mostraram que os pacientes que tiveram COVID-19 antes da vacinação podem apresentar um pior estado periodontal quando comparados a pacientes no mesmo ambiente clínico sem histórico de COVID-19. No entanto, um estudo mais extenso deve ser realizado para confirmar tal achado com maior número de participantes.

Influence of sealer type on treatment outcome of teeth with apical periodontitis: a systematic review

Abstract The purpose of this article was to Evaluate the influence of sealer on the outcome of non-surgical endodontic treatment or retreatment of permanent teeth with apical periodontitis (PROSPERO registration: CRD42020205951). Methodology: A systematic review of original clinical studies was carried out following PRISMA guidelines to answer whether the type of sealer used in endodontic treatment or retreatment influences the repair of apical periodontitis determined by clinical and radiographic parameters. Electronic searches were performed in PubMed, Embase, Web of Science, Scopus, and the Cochrane Library database, until May 2023. Gray literature and a hand search of reference lists were also performed. The risk of bias was assessed using Cochrane RoB2 for randomized trials and the Newcastle-Ottawa Scale (NOS) for prospective and retrospective cohort and case-control studies. Results: Among 1046 studies, a total of 819 were selected by title and abstract, resulting in 23 for full-text review. In total, 11 studies met the inclusion criteria (1467 patients/teeth with apical periodontitis). The quality assessment using RoB2 included five randomized control trials, of which four had medium risk and one had a low risk of bias. According to the NOS scale, five studies were classified as low risk and one study was considered as medium risk of bias. The sealer type and obturation techniques varied, and the mean follow-up time was 3.7 years. Most studies used two-dimensional radiographic criteria to assess the treatment outcome sealers and not cements. Eight studies did not find significant differences when comparing cements. The healing rates ranged from 56.7% to 90%. Conclusions: The results of this review support that the current endodontic sealers do not seem to influence the treatment outcome of permanent teeth with apical periodontitis. Although the studies had medium and low risk of bias, the results should be interpreted with caution. More randomized studies of long-term outcomes comparing filling materials are needed to strengthen this claim and allow for a meta-analysis.

Resumo O objetivo deste artigo foi avaliar a influência do cimento no resultado do tratamento ou retratamento endodôntico não cirúrgico de dentes permanentes com periodontite apical (registro PROSPERO: CRD42020205951). Metodologia: Uma revisão sistemática de estudos clínicos originais foi realizada seguindo as diretrizes PRISMA para responder se o tipo de cimento usado no tratamento ou retratamento endodôntico influencia a reparação da periodontite apical determinada por parâmetros clínicos e radiográficos. Pesquisas eletrônicas foram realizadas no PubMed, Embase, Web of Science, Scopus e no banco de dados Cochrane Library, até maio de 2023. A literatura cinza e uma pesquisa manual das listas de referências também foram realizadas. O risco de viés foi avaliado usando Cochrane RoB2 para os estudos randomizados e Newcastle-Ottawa Scale (NOS) para coorte prospectiva e retrospectiva e estudos de caso-controle. Resultados: Entre 1.046 estudos, um total de 819 foram selecionados por título e resumo, resultando em 23 para revisão de texto completo. No total, 11 estudos preencheram os critérios de inclusão (1.467 pacientes/dentes com periodontite apical). A avaliação de qualidade usando RoB2 incluiu cinco estudos randomizados de controle, dos quais quatro tinham risco médio e um tinha baixo risco de viés. De acordo com a escala NOS, cinco estudos foram classificados com baixo risco e um estudo foi considerado com médio risco de viés. O tipo de cimento e as técnicas de obturação variaram, e o tempo médio de acompanhamento foi de 3,7 anos. A maioria dos estudos utilizou critérios radiográficos bidimensionais para avaliar o resultado do tratamento. Oito estudos não encontraram diferenças significativas ao comparar os cimentos. As taxas de reparação variaram de 56,7% a 90%. Conclusões: Os resultados desta revisão suportam que os cimentos endodônticos atuais não parecem influenciar o resultado do tratamento de dentes permanentes com periodontite apical. Embora os estudos tiveram médio e baixo risco de viés, os resultados devem ser interpretados com cautela. Mais estudos randomizados de resultados de longo prazo comparando materiais de obturação são necessários para fortalecer essa afirmação e permitir uma meta-análise.

Disinfection and Shaping of Vertucci Class II Root Canals after Preparation with Two Instrument Systems and Supplementary Ultrasonic Activation of Sodium Hypochlorite.

INTRODUCTION: This study compared disinfection and shaping after root canal preparation with either XP-endo Shaper or TruNatomy instrument systems, supplemented by ultrasonic activation of sodium hypochlorite (NaOCl) with either stainless-steel (SS) or nickel-titanium (NiTi) inserts. METHODS: Mesial roots from mandibular molars with Vertucci class II configuration were divided into 2 groups (n = 24) based on anatomically paired micro-computed tomography (micro-CT) analyses. Pre and postpreparation micro-CT scans were obtained to evaluate the shaping performance. The canals were contaminated with a mixed bacterial culture for 30 days and then subjected to preparation with either XP-endo Shaper or TruNatomy instruments using NaOCl irrigation. Supplementary ultrasonic activation of NaOCl was conducted using either an SS (TruNatomy group) or NiTi (XP-endo Shaper group) insert. Bacteriological samples were taken from the canals before preparation (S1), after preparation (S2), and after the supplementary approach (S3). Bacterial reduction was evaluated using a quantitative real-time polymerase chain reaction. RESULTS: Preparation with both instrument systems significantly reduced bacterial counts (P < .01). After preparation, 36% (TruNatomy) and 35% (XP-endo Shaper) were negative for bacteria. These values increased to 59% and 65% after ultrasonic activation with the SS and NiTi inserts, respectively. The quantitative data in S2 showed that XP-endo Shaper promoted a significantly higher bacterial reduction than TruNatomy (P < .05). No significant intragroup differences were observed after ultrasonic activation (P > .05), probably because the SS insert promoted a significantly higher S2-to-S3 reduction than the NiTi insert (P < .01). Micro-CT analysis revealed no significant differences in the unprepared areas between the groups (P > .05). CONCLUSIONS: The XP-endo Shaper caused a significantly higher bacterial reduction than TruNatomy in Vertucci class II canals. Better antibacterial results after ultrasonic activation were observed for the SS ultrasonic inserts than for the NiTi inserts.

Shaping ability of BlueShaper, TruNatomy, DC Taper and HyFlex EDM in long oval canals: An ex vivo study.

AIM: This study evaluated and compared the shaping ability of four rotary instrument systems in long-oval root canals using microcomputed tomographic (micro-CT) evaluation. Currently, there is no data available on the canal shaping abilities of BlueShaper and DC Taper instruments. METHODOLOGY: Sixty-four single-rooted mandibular premolars were matched based on similar root canal morphologic features as determined by (micro-CT) and randomly assigned to 1 of 4 experimental groups (n = 16) according to the instrument system used: BlueShaper, TruNatomy, DC Taper and HyFlex EDM One File. Changes in the root canal surface and volume, remaining dentine thickness, and number of prepared areas were assessed. RESULTS: No significant differences were found amongst the four instrument systems for the parameters evaluated (p > .05). There was a significant reduction in the number of unprepared areas and the remaining dentine thickness after each increase in size of the instruments tested (p < .05). CONCLUSIONS: The four instrument systems perform similarly in long oval root canals. Although none could prepare all canal walls, larger preparations incorporated significantly more surfaces in the final shape.

Influence of brushing motions on the shaping of oval canals by rotary and reciprocating instruments.

OBJECTIVE: The effects of brushing on shaping with three different instruments were assessed in oval canals. DESIGN: Mandibular incisors were assigned to 6 groups (n = 12/group) according to the system, each one with or without brushing: Reciproc Blue, VDW.Rotate, and Race EVO. Micro-computed tomography was performed before and after preparation. RESULTS: Brushing strokes caused no increase in canal volume, surface area, and structure model index independently of the system (p > 0.05), except for RaCe EVO in the full canal surface area (p < 0.05). Brushing did not increase the prepared areas (p > 0.05), except for Reciproc in the apical canal (p < 0.05). Reciproc with no brushing exhibited less pericervical dentin than with brushing (p < 0.05), while RaCe EVO with brushing resulted in less remaining dentin (p < 0.05). CONCLUSIONS: The brushing motion had no effects on the overall shaping performance of the 3 instruments tested. An exception was the increase in prepared surface area in the apical canal segment when the Reciproc instrument was used with brushing strokes.

Influence of a High-fat Diet in the Progression of Apical Periodontitis.

INTRODUCTION: This study evaluated the effects of a high-fat diet (HFD) on the progression of apical periodontitis (AP) in rats. METHODS: Eight-week old Wistar rats (N = 24) were included in this study. Half of the animals received an HFD and the other half a control diet (CD). AP lesions were induced 8 weeks later by creating pulp exposure of the mandibular left first molars. The animal's body mass was verified on a weekly basis. After 21 and 40 days, the animals were sacrificed. Blood was collected for biochemical tests, and the liver was removed for hepatic triglycerides analysis. The left hemimandibles were removed, radiographed, and then prepared for histologic evaluation. The right hemimandibles (region near molars) were removed for bone mineral density analysis by dual-energy X-ray absorptiometry. RESULTS: Radiographs showed that AP lesions were significantly larger in the HFD group compared with the CD group (P < .05). Histologic analysis confirmed that the AP lesions were larger and revealed a more severe inflammatory infiltrate in the HFD group. Bone mineral density was reduced in the HFD group compared with the CD groups (P < .05). The HFD resulted in a significant increase in body mass (P < .05), liver mass (P < .05), relative liver mass (P < .05), and hepatic triglycerides (P < .05). The levels of triglycerides and very-low-density lipoprotein were significantly higher in the 40-day HFD group compared with the 21-day HFD and 21- and 40-day CD groups (P < .05). CONCLUSIONS: Findings suggest that an HFD can influence the progression and severity of AP.

Cytotoxicity, antibacterial and physicochemical properties of a new epoxy resin-based endodontic sealer containing calcium hydroxide.

BACKGROUND: This study evaluated the cytotoxicity, antibacterial and physicochemical properties of a new epoxy resin-based endodontic sealer containing calcium-hydroxide Sealer Plus. AH Plus was used as a reference for comparison. MATERIAL AND METHODS: Cytotoxicity evaluation was performed according to ISO-10993-5 specifications using MTT assay to check the 3T3 cells viability at 1- to 4-week periods. Antibacterial activity was evaluated using a direct contact test against Enterococcus faecalis. Radiopacity, solubility and flow evaluations were performed according to ISO-6876/2012 specifications. Setting time was assessed following the ANSI/ADA-standard-n.57. The pH level was measured at 3,24,48,72, and 168 hours. Data were statistically analyzed using t-test. The significance level adopted was P<0.05. RESULTS: AH Plus and Sealer Plus showed cytotoxic effects after 24 hours and 1 week of manipulation and become noncytotoxic after 2 weeks. No differences were observed in the cytotoxicity of both tested sealers (P>0.05). Direct contact results revealed that both freshly prepared sealers has antibacterial effects against Enterococcus faecalis. However, after 7 days both sealers had lost much of their antibacterial effects. Although AH Plus presented higher radiopacity and flow than Sealer Plus (P<0.05), both sealers showed minimum required values. No differences were observed in the solubility of both sealers (P>0.05). AH Plus showed a higher setting time when compared to Sealer Plus (P<0.05). AH Plus and Sealer Plus showed a neutral pH during all tested periods (P<0.05). CONCLUSIONS: It can be concluded that Sealer Plus showed suitable properties to be used as an endodontic sealer, comparable with those obtained by AH Plus. Key words:Cytotoxicity, root canal filling materials, root canal obturation.

Canal Transportation, Unprepared Areas, and Dentin Removal after Preparation with BT-RaCe and ProTaper Next Systems.

INTRODUCTION: This study compared the shaping ability of ProTaper Next (Dentsply Sirona, Tulsa, OK) and BT-RaCe (FKG Dentaire, La Chaux-de-Fonds, Switzerland) instrument systems in the mesial canals of mandibular molars using micro-computed tomographic (micro-CT) imaging. METHODS: A total of 17 type IV mesial roots of extracted first mandibular molars were scanned using micro-CT imaging before and after root canal preparation with the 2 instrument systems. Both systems were used in the same root but alternating the mesial canals from root to root. The following parameters were analyzed: root canal volume, surface area, unprepared surface areas, transportation, canal/root width ratio, and preparation time. RESULTS: There were no statistically significant differences between the 2 systems for all evaluated parameters (P > .05). The unprepared surface areas for the full canal length and the apical 5-mm segment were 33% and 14% for BT-RaCe and 31% and 14% for ProTaper Next, respectively. After preparation, all root canals had a diameter that was not larger than 35% of the root diameter at the coronal and middle segments. CONCLUSIONS: The 2 systems showed no differences in any of the evaluated shaping parameters. None of the tested systems put the roots at risk of fracture because of excessive dentin removal.