RESUMO
Screener, a board game supplemented with online resources, was introduced and distributed by the Brazilian Society of Pharmacology and Experimental Therapeutics to postgraduate programs as an instructional tool for the process of drug discovery and development (DDD). In this study, we provided a comprehensive analysis of five critical aspects for evaluating the quality of educational games, namely: 1) description of the intervention; 2) underlying pedagogical theory; 3) identification of local educational gaps; 4) impact on diverse stakeholders; and 5) elucidation of iterative quality enhancement processes. We also present qualitative and quantitative assessments of the effectiveness of this game in 11 postgraduate courses. We employed the MEEGA+ online survey, comprising thirty-three close-ended unipolar items with 5-point Likert-type response scales, to assess student perceptions of the quality and utility of Screener. Based on 115 responses, the results indicated a highly positive outlook among students. In addition, we performed a preliminary evaluation of learning outcomes in two courses involving 28 students. Pre- and post-quizzes were applied, each consisting of 20 True/False questions directly aligned with the game's content. The analysis revealed significant improvement in students' performance following engagement with the game, with scores rising from 8.4 to 13.3 (P<0.0001, paired t-test) and 9.7 to 12.7 (P<0.0001, paired t-test). These findings underscore the utility of Screener as an enjoyable and effective tool for facilitating a positive learning experience in the DDD process. Notably, the game can also reduce the educational disparities across different regions of our continental country.
Assuntos
Descoberta de Drogas , Aprendizagem , Humanos , Escolaridade , Brasil , Suplementos NutricionaisRESUMO
Screener, a board game supplemented with online resources, was introduced and distributed by the Brazilian Society of Pharmacology and Experimental Therapeutics to postgraduate programs as an instructional tool for the process of drug discovery and development (DDD). In this study, we provided a comprehensive analysis of five critical aspects for evaluating the quality of educational games, namely: 1) description of the intervention; 2) underlying pedagogical theory; 3) identification of local educational gaps; 4) impact on diverse stakeholders; and 5) elucidation of iterative quality enhancement processes. We also present qualitative and quantitative assessments of the effectiveness of this game in 11 postgraduate courses. We employed the MEEGA+ online survey, comprising thirty-three close-ended unipolar items with 5-point Likert-type response scales, to assess student perceptions of the quality and utility of Screener. Based on 115 responses, the results indicated a highly positive outlook among students. In addition, we performed a preliminary evaluation of learning outcomes in two courses involving 28 students. Pre- and post-quizzes were applied, each consisting of 20 True/False questions directly aligned with the game's content. The analysis revealed significant improvement in students' performance following engagement with the game, with scores rising from 8.4 to 13.3 (P<0.0001, paired t-test) and 9.7 to 12.7 (P<0.0001, paired t-test). These findings underscore the utility of Screener as an enjoyable and effective tool for facilitating a positive learning experience in the DDD process. Notably, the game can also reduce the educational disparities across different regions of our continental country.
RESUMO
INTRODUCTION: This scoping review aimed to map the evidence about the microbiota found in persistent endodontic infections. METHODS: The study protocol was prospectively registered and is available at https://osf.io/3g2cp. The electronic search was performed in MEDLINE via PubMed, Lilacs, BBO, Scopus, Web of Science, Cochrane Library, and Embase. The eligibility criteria were based on the PCC acronym, where P (Population) represents patients with teeth presenting persistent endodontic infection, C (Concept) represents microbial profile, and C (Context) represents undergoing endodontic retreatment. Clinical studies that evaluated the microbial profile of samples collected from root canals of teeth undergoing retreatment, using classical or molecular methods, were included. Studies that did not show a minimum period of 1 year between primary endodontic treatment and retreatment or did not radiographically evaluate the quality of primary root canal filling were excluded. Two reviewers independently selected the articles and collected data. RESULTS: From a total of 957 articles, 161 were read in full, and 32 studies were included. The most prevalent species were Enterococcus faecalis, Parvimonas micra, Porphyromonas endodontalis, Porphyromonas gingivalis, Prevotella intermedia, Dialister invisus, Propionibacterium acnes, Tannerella forsythia, and Treponema denticola. Cases with symptomatology or inadequate root canal filling presented an increase in specific bacterial species compared to those with no symptomatology or adequate filling. A greater number of microorganisms was observed in teeth with inadequate coronal restoration compared to those with adequate restoration. CONCLUSIONS: Persistent endodontic infections have a polymicrobial profile identified by the commonly used methods for bacterial detection/identification and are subject to the limitations present in each of those methods.
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Cavidade Pulpar , Porphyromonas gingivalis , Humanos , Cavidade Pulpar/microbiologia , Prevotella intermedia , Porphyromonas endodontalisRESUMO
OBJECTIVES: The aim of this study is to answer the question: "Is guided endodontics an effective technique for locating calcified canals?". METHODS: A systematic search was carried out by two independent authors in PubMed, Web of Science, Scopus, and Scielo databases. According to the PIOS criteria, observational studies, ex vivo studies, clinical case reports, and case series were included. The quality of evidence of observational studies, case reports, and case series were assessed using the respective Joanna Briggs Institute critical appraisal tool, and a previous personalized tool was used to assess the quality of the ex vivo studies. RESULTS: Forty-five studies were included. Of them, 21 were clinical case reports, 11 case series, 12 ex vivo studies, and 1 cohort study. Of the 45 studies analyzed, 43 reported that guided endodontics is an effective and precise technique to access the permeable portion of calcified canals. Only 2 studies report accidents or failures related to the use of endodontic guides. CONCLUSIONS: Guided endodontics allows conservative access, minimizes accidents, and is effective in locating calcified canals; however, it is a technique that still presents limitations. CLINICAL RELEVANCE: Guided endodontics has been proposed as a simple and effective technique for the treatment of calcified canals. The expansion of this technique requires knowing its benefits and limitations to ensure success and avoid accidents.
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Endodontia , Tratamento do Canal Radicular , Humanos , Cavidade Pulpar , Estudos de Coortes , Tomografia Computadorizada de Feixe CônicoRESUMO
AIM: To evaluate the influence of ultraconservative access cavities (UltraAC) on canal shaping and filling ability and load capacity of mandibular molars after root canal preparation with XP-endo Shaper (XP) or Reciproc (RC), under simulated clinical conditions. Traditional access cavities (TradAC) were used for comparison. METHODOLOGY: Forty extracted mandibular molars were scanned by micro-computed tomographic and, based on similar anatomical features, were divided into four groups (n = 10), according to the type of access cavity and canal instrumentation protocol: TradAC/RC, TradAC/XP, UltraAC/RC and UltraAC/XP. All root canal procedures were performed with the teeth placed in a dental mannequin. Teeth were scanned after root canal instrumentation and filling. Unprepared canal area, dentine removed, accumulated hard tissue debris (AHTD), canal transportation, presence of voids and filling material remnants within the pulp chamber were analysed. After restorative procedures, the teeth were subjected to thermomechanical cycling and to a load capacity test. Statistical analyses were performed using two-way anova test, considering the randomized blocks design (P < 0.05). RESULTS: The percentage of unprepared canal area was significantly lower in TradAC groups when compared to UltraAC groups (P < 0.05), regardless of the instrument used. The UltraAC/XP group had significantly lower percentage of root dentine removed when compared to other groups (P < 0.05). UltraAC/XP and TradAC/XP groups had significantly lower percentages of AHTD than UltraAC/RC and TradAC/RC groups (P < 0.05). Regarding canal transportation, in the MB root canals, the TradAC/XP group had significantly lower values than other groups (P < 0.05). In general, in ML and distal root canals, TradAC/XP and UltraAC/XP groups had significantly lower values of canal transportation when compared to other groups (P < 0.05). Moreover, the UltraAC/RC had the greatest canal transportation values in MB and distal canals. The UltraAC groups had significantly greater percentages of voids and volume of remaining root filling material within the pulp chamber after cleaning procedures than TradAC groups (P < 0.05). There was no difference in the load capacity amongst groups (P < 0.05). CONCLUSION: The UltraAC/XP and UltraAC/RC groups had significantly greater areas of unprepared canal walls, significantly more voids and volume of root filling material remnants within the pulp chamber after canal filling. UltraAC/XP was associated with significantly less root dentine removal and significantly more AHTD whilst TradAC/XP had overall significantly less canal transportation. No differences were observed in the load capacity amongst groups.
Assuntos
Cavidade Pulpar , Preparo de Canal Radicular , Dente Molar/diagnóstico por imagem , Dente Molar/cirurgia , Obturação do Canal Radicular , Microtomografia por Raio-XRESUMO
AIM: To evaluate the influence of pH variation on the solubility and water sorption of a premixed calcium silicate-based root canal sealer (EndoSequence BC Sealer) compared to the gold standard based on epoxy resin (AH Plus Jet) after immersion in distilled water and phosphate-buffered saline (PBS). METHODOLOGY: Solubility and water sorption were evaluated after immersion in distilled water or PBS at several pHs (5, 7 and 12) and the values were calculated as percentages of the original mass after 24 h, 7 and 30 days of immersion. The crystalline structures present in the sealers and surface precipitates were assessed by X-ray diffraction. The Shapiro-Wilk's test revealed that data were normally distributed; thus, statistical analysis was performed using one-way anova and Tukey's tests or independent t-test, assuming a 5% α-error. RESULTS: EndoSequence BC Sealer was associated with significantly greater water sorption and solubility compared to AH Plus Jet in all tested conditions (P < 0.05). The acid environment increased the 24 h solubility of EndoSequence BC Sealer immersed in PBS (P < 0.05) and did not induce significative changes in the water sorption (P > 0.05). Alkaline pH reduced the solubility of EndoSequence BC Sealer and increased that of AH Plus Jet at all experimental times and soaking media (P < 0.05). Alkaline environment also significantly increased the water sorption of AH Plus Jet immersed in PBS (P < 0.05). Immersion in PBS significantly reduced the solubility of EndoSequence BC Sealer and significantly increased that of AH Plus Jet (P < 0.05). Precipitates on the surface of EndoSequence BC Sealer corresponding to hydroxyapatite and calcium carbonate were detected after immersion in PBS at pH 5 and 7 for 30 days. CONCLUSIONS: EndoSequence BC Sealer had significantly greater solubility and water sorption than AH Plus Jet. Although the alkaline pH and soaking media directly influenced the solubility and water sorption of the sealers, the solubility of AH Plus Jet remained within the limits recommended by ISO 6876, whilst the solubility of the EndoSequence BC Sealer did not comply with ISO recommendations in all the conditions tested.
Assuntos
Materiais Restauradores do Canal Radicular , Compostos de Cálcio , Cavidade Pulpar , Resinas Epóxi , Teste de Materiais , Silicatos , Solubilidade , ÁguaRESUMO
AIM: To compare six reciprocating instruments regarding their geometric design, metallurgical characteristics, mechanical behaviour and ability to prepare root canals. METHODOLOGY: A total of 246 new 25-mm NiTi instruments (41 per group) from six reciprocating systems (Reciproc, Reciproc Blue, One Files, One Files Blue, Reverso Silver, and WaveOne Gold) were evaluated throughout a multimethod approach regarding their design using stereomicroscopy (number of blades and helix angle) and scanning electron microscopy (blades symmetry, cross section and surface finishing), nickel-titanium composition, phase transformation temperatures, mechanical performance (cyclic fatigue, torsional and bending resistance) and unprepared canal surface area on anatomically matched mandibular molars assessed by micro-CT. One-way ANOVA and post hoc Tukey's or Mood's median tests were selected depending on sample distribution with significance level set at 5%. RESULTS: The instruments had similarities regarding their metal composition and unprepared canal area, whilst differences in phase transformation temperatures and geometric design (number of blades, surface finishing and tip geometry) were observed. Overall, no difference was observed regarding the maximum torque values (P > 0.05), whilst One Files (72 s) and One Files Blue (414 s) had the shortest and longest times to fracture, respectively (P < 0.05). Similar angles of rotation were observed in Reciproc (310°), One Files (285°) and Reverso Silver (318°) instruments (P > 0.05), which were significantly lower than Reciproc Blue (492°), One Files Blue (456°) and WaveOne Gold (492°; P < 0.05). Maximum bending load demonstrated that Reciproc Blue (201.3 gf) was significantly more flexible that the other instruments (P < 0.05). CONCLUSION: Although there were similarities in metal composition and percentage of unprepared canal surface, the instruments had differences in the overall geometric design, phase transformation temperatures and in the four mechanical resistance parameters (time to fracture, maximum torque, angle of rotation and maximum bending load).
Assuntos
Instrumentos Odontológicos , Preparo de Canal Radicular , Desenho de Equipamento , Teste de Materiais , Estresse MecânicoRESUMO
BACKGROUND: Orthodontic tooth movements are performed by applying forces on teeth, which may cause alterations within the dental pulp. Previously published systematic reviews on the subject only included a small number of studies that assessed pulp status through reliable diagnostic methods. Since then, new evidence has been published, and a further systematic review on the subject is necessary. OBJECTIVES: To evaluate whether there is scientific evidence to support the possibility that orthodontic tooth movements could induce pulp necrosis. METHODS: A systematic search of articles published until June 2020 was performed using MeSH and free terms in the PubMed, Cochrane Library, LILACS, SciELO, Web of Science, EMBASE, Open Grey and Grey Literature databases. Randomized clinical trials (RCTs), nonrandomized clinical trials (nRCTs) and longitudinal (prospective or retrospective) studies that evaluated the pulp status of teeth subjected to orthodontic movements using laser Doppler flowmetry or pulse oximetry were included. The revised Cochrane risk of bias tools for randomized trials (RoB 2) and nonrandomized interventions (ROBINS-I) were used to assess the quality of the included studies. Relevant findings were summarized and evaluated. The overall quality of evidence was assessed through the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) tool. RESULTS: Initial screening of databases resulted in 353 studies. In total, 285 studies were excluded because they were duplicates. Of 68 eligible papers, fourteen met the inclusion criteria and were selected for full-text reading. Two studies were excluded due to the methods used to evaluate pulp status. Twelve studies (five RCTs, one nRCT and six prospective) were included. Four RCTs were classified as having an unclear risk of bias and one as having a high risk of bias. The nRCT was classified as having a low risk of bias. Two prospective studies were classified as having a moderate risk of bias and four as having a serious risk of bias. The GRADE analysis demonstrated a low to very low quality of evidence. DISCUSSION: Significant limitations regarding the randomization processes within the included RCTs and a lack of control of confounders on most nonrandomized and longitudinal studies were verified. CONCLUSIONS: This systematic review indicates that orthodontic movements do not induce loss of pulp vitality with low to very low certainty of evidence.
Assuntos
Necrose da Polpa Dentária , Técnicas de Movimentação Dentária , Humanos , Fluxometria por Laser-Doppler , Técnicas de Movimentação Dentária/efeitos adversosRESUMO
AIM: To evaluate the correlation between the volume of dental hard tissues removed and the fracture resistance of mandibular molar teeth with ultraconservative (UltraAC) or traditional (TradAC) access cavity preparations. METHODOLOGY: Sixty recently extracted and intact mandibular first molars were scanned in a microcomputed tomographic (micro-CT) device, anatomically matched and assigned at random to 2 groups (n = 30), according to the access cavity type: UltraAC or TradAC. After access preparation, mesial and distal canals were prepared using Reciproc instruments and a new scan was taken. The volumes of pulp chamber and dental hard tissues in each specimen were measured before and after the experimental procedures, and the percentage volume reduction of hard tissues calculated for the entire tooth and for the crown separately. Teeth were then root filled, restored and subjected to fracture resistance tests in an universal testing machine. The force required to fracture was recorded in Newtons (N). The adherence of the variables to a Gaussian curve was verified using a Shapiro-Wilk test. Skewed data were analysed with nonparametric Wilcoxon signed rank or Spearman correlation tests, whilst the normally distributed data were analysed with a dependent samples Student t-test. Level of significance was set at 5%. RESULTS: Pre-operatively, no difference was observed between groups regarding the volume of pulp canal space or dental hard tissues (P > 0.05). After access preparation, volumes of the removed hard tissues from the entire tooth and from the crown were significantly greater in teeth prepared with TradAC than with UltraAC (P < 0.05). No significant difference was observed in the fracture resistance values between TradAC (902.9 ± 347.8 N) and UltraAC (948.7 ± 405.7 N) groups (P = 0.975). The Spearman test was unable to identify a correlation between fracture resistance and percentage volume of removed dental hard tissues in the entire root (P = 0.525, r = -0.084) or only in the crown (P = 0.152, r = -0.187). CONCLUSION: The volume of hard dental tissues removed, although greater in teeth with TradAC compared to UltraAC, did not correlate with the fracture resistance results, indicating that a minimally invasive access cavity did not increase the resistance of restored mandibular first molars to fracture.
Assuntos
Dente Molar , Preparo de Canal Radicular , Cavidade Pulpar , Dentina , Humanos , Dente Molar/diagnóstico por imagem , Dente Molar/cirurgia , Microtomografia por Raio-XRESUMO
AIM: To compare the ProTaper Next (PTN) system with a replica-like and a counterfeit system regarding design, metallurgy, mechanical performance and shaping ability. METHODOLOGY: Replica-like (X-File) and counterfeit (PTN-CF) instruments were compared to the PTN system regarding design (microscopy), phase transformation temperatures (differential scanning calorimetry), nickel-titanium ratio (energy-dispersive X-ray spectroscopy), cyclic fatigue, torsional resistance, bending strength, and untouched canal areas in extracted mandibular molars (micro-CT). anova, post hoc Tukey's and Kruskal-Wallis tests were used according to normality assessment (Shapiro-Wilk test) with the significance level set at 5%. RESULTS: Overall similarities in design and nickel-titanium (Ni/Ti) ratio were observed amongst instruments with the X-File having a smoother surface finish. PTN and PTN-CF had mixed austenite plus R-phase (R-phase start approximately at 45 ºC and near 30 ºC, respectively), whilst X-File instruments were austenitic (R-phase started at approximately at 17 ºC) at room temperature (20 ºC). PTN-CF had the greatest inconsistency in the phase transformation temperatures. Time to fracture of PTN-CF X2 and X3 was significantly shorter than PTN and X-File instruments (P < 0.05), whilst no difference was noted in maximum torque to fracture amongst the tested systems (P > 0.05). X-Files and PTN-CF had a stress-induced phase change during bending load. Mean unprepared surface areas of root canals were 25.8% (PTN), 31.1% (X-File) and 32.5% (PTN-CF) with no significant difference amongst groups (P > 0.05). CONCLUSION: Similarities amongst the systems were noted in the Ni/Ti ratio and maximum torque to fracture, whilst differences were observed in the design, phase transformation temperatures and mechanical behaviour. The ProTaper Next counterfeit instruments could be considered as the less secure system considering its low-cyclic fatigue resistance. Apart from these differences, the unprepared canal surface areas, obtained with the tested systems, were similar.
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Ligas Dentárias , Preparo de Canal Radicular , Desenho de Equipamento , Teste de Materiais , Metalurgia , Estresse Mecânico , Titânio , Microtomografia por Raio-XRESUMO
AIM: To validate a new method for the evaluation of pulp tissue debridement in the root canals of extracted teeth using an impregnation protocol involving potassium triiodide, a radiocontrast solution known as Lugol's, combined with micro-computed tomographic (micro-CT) imaging. METHODOLOGY: The impact of NaOCl on the radiopacity of Lugol's solution was assessed using a two-fold dilution series of Lugol in distilled water and 5.25% NaOCl, which were then pipetted into transparent dishes and radiographed. To verify the influence of Lugol on the proteolytic effect of NaOCl, a dissolution test was performed using fresh bovine meat. Ten slices did not undergo any tissue processing, whilst twenty slices were fixed in formaldehyde for 24 h. After that, 10 of them were immersed in Lugol for another 24 h. Then, all specimens were placed in NaOCl and the time required for a complete tissue dissolution was recorded. For the last experiments (histological validation and micro-CT assessment), 8 extracted mandibular premolars with formerly vital pulps were immersed in buffered formalin, scanned in a micro-CT device, accessed, immersed in Lugol for 7 days and scanned again. Then, the root canals of 5 teeth were prepared and scanned, and the volume of remaining pulp tissue identified and quantified, whilst 3 teeth were histologically processed. The same specimens were subjected to histological assessment, and the images of the histologic sections were registered with the corresponding micro-CT images to verify whether the pulp tissue in the histological sections matched its counterpart in the Lugol-impregnated tissues identified in the micro-CT slices. RESULTS: There was no discernible effect on radiopacity when NaOCl was mixed with Lugol's solution. Tissue processing did not affect the time required for the complete dissolution of fresh bovine meat. Histological evaluation revealed a correlation between micro-CT and histological images confirming the identification of Lugol-impregnated pulp tissue in micro-CT images. CONCLUSIONS: The radiocontrast Lugol's solution was unaffected by NaOCl and did not interfere with its soft tissue dissolution capability. The impregnation protocol using Lugol's solution allowed the visualization of pulp tissue on the micro-CT images and the identification of pulp remnants after chemical-mechanical canal procedures.
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Cavidade Pulpar , Preparo de Canal Radicular , Animais , Bovinos , Desbridamento , Polpa Dentária , Cavidade Pulpar/diagnóstico por imagem , Microtomografia por Raio-XRESUMO
AIM: To evaluate the bending, buckling and torsional resistance of ProGlider (PG) (Dentsply Sirona, Ballaigues, Switzerland), R-Pilot (RP) (VDW, Munich, Germany) and WaveOne Gold Glider (WOGG) (Dentsply Sirona). METHODOLOGY: Ninety instruments were used: 30 PG (size 0.16, .02v taper), 30 RP (size 0.125, .04 taper) and 30 WOGG (size 0.15, .02v taper). The bending resistance test was performed on 10 randomly selected instruments of each system according to ISO 3630-1 specifications. For the buckling resistance test, a loading was applied in the axial direction of each instrument using a universal test machine, with a 20 N cell and 15 mm min-1 speed, in the axial direction. When a lateral elastic displacement of 1 mm occurred, the force was registered. The torsional resistance test was performed according to ISO 3630-1 specifications. Statistical analysis was performed using one-way anova and post hoc Student-Newman-Keuls test (P < 0.05). RESULTS: WOGG had the lowest bending resistance, whilst RP had the highest bending resistance (P < 0.05). RP also had the highest buckling resistance, and WOGG had the lowest (P < 0.05). PG had intermediate results regarding bending and buckling resistance, with significant differences to RP and WOGG (P < 0.05). RP had the highest torsional strength and the lowest angular deflection when compared to PG and WOGG (P < 0.05). No differences in the torsional strength and angular deflection were observed between WOGG and PG (P> 0.05). CONCLUSION: The glide path instruments had different behaviours in term of bending, buckling and torsional resistance.
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Instrumentos Odontológicos , Fenômenos Mecânicos , Ligas Dentárias , Desenho de Equipamento , Alemanha , Ouro , Humanos , Teste de Materiais , Preparo de Canal Radicular , Titânio , Torção MecânicaRESUMO
AIM: To evaluate the use of a reduced taper endodontic instrument system (Bassi Logic™ .03 taper) and expandable heat-treated system (XP-endo Shaper) on the ability to shape canals in mandibular molars, by means of microcomputed tomography (micro-CT) analysis. The Reciproc system was used as the reference for comparison. METHODOLOGY: Twenty-four mandibular molars were scanned in a micro-CT, matched based on similar anatomical features and sorted into three groups (n = 8 per group), according to root canal preparation system: Bassi Logic™ .03, XP-endo Shaper and Reciproc. The teeth were mounted onto a mannequin and the pulp chambers were accessed with traditional access cavities. In Bassi Logic™ .03 and Reciproc groups, mesial canals were prepared with size 25, .03 taper or R25 (size 25, .08v taper) instruments and the distal root canal with size 25, .03 taper and size 40, .03 taper or R25 and R40 (size 40, .06v taper), respectively. In XP-endo Shaper groups, all root canals were prepared with XP-endo Shaper (size 30, .04v taper). After root canal preparation, the teeth were rescanned. The percentage of untouched canal areas and the percentage of removed dentine were evaluated separately for mesial and distal root canals. The data were analysed using one-way anova and Tukey tests (P < 0.05). RESULTS: The Bassi Logic™ .03 group was associated with a greater percentage of untouched canal areas when compared to XP-endo Shaper and Reciproc groups for mesial and distal root canals (P < 0.05), but no differences were found between XP-endo Shaper and Reciproc groups (P > 0.05). No significant difference was observed in the percentage of dentine removed amongst the groups for mesial and distal root canals (P > 0.05). CONCLUSION: The use of a reduced taper system (Bassi Logic™ .03) during root canal preparation resulted in a greater percentage of untouched canal areas when compared to XP-endo Shaper and Reciproc instruments. No differences were observed amongst the systems regarding the percentage of dentine removed.
Assuntos
Cavidade Pulpar , Preparo de Canal Radicular , Movimento Celular , Cavidade Pulpar/diagnóstico por imagem , Dente Molar/diagnóstico por imagem , Dente Molar/cirurgia , Microtomografia por Raio-XRESUMO
AIM: To assess the impact of conservative endodontic access cavities (CEC) and truss access cavities (TAC) during root canal treatment performed on mandibular molars in terms of: ability to shape and fill root canals, microbial reduction in canals, and cleaning of the pulp chamber. In addition, the fracture resistance of the teeth after coronal restoration was assessed. Traditional endodontic cavities (TEC) were used as a reference technique for comparison. METHODOLOGY: Thirty extracted intact mandibular molars were scanned in a microcomputed tomography device (micro-CT), matched based on similar anatomical features and assigned to TEC, CEC or TAC groups (n = 10). The specimens were accessed accordingly, and root canals were contaminated with bacterial suspensions of Enterococcus faecalis (21 days). Subsequently, the first microbial sample was collected from root canals (S1). The canals were initially prepared with Reciproc Blue R25 instrument followed by a second instrumentation using Reciproc Blue R40. Eight mL of 0.5% NaOCl were used as an irrigant for each instrument. A final irrigation protocol was performed with 2 mL of 0.5% NaOCl, 2 mL of 17% EDTA and another 2 mL of 0.5% NaOCl. Microbial samples were collected from root canals after R25 (S2), R40 (S3) and final irrigation (S4). The teeth were rescanned after S4. Then, root canals were filled, rescanned, restored and the teeth subjected to fracture resistance tests. The statistical analysis was performed with type I negative binomial and beta 0-1 inflation regression models for microbiological analysis. Instrumentation, filling and resistance to fracture results were subjected to anova and Tukey tests (P < 0.05). RESULTS: S4 revealed no significant variations in microbial reduction amongst the groups (P > 0.05). TEC had a significantly lower percentage of unprepared surface area than CEC (P < 0.05). No differences were found regarding the percentage of dentine removed, transportation, centring ability and filling voids amongst the groups (P > 0.05). The TEC group had a significantly lower volume of remaining root filling material within the pulp chamber than CEC and TAC groups (P < 0.05). There was no difference regarding fracture resistance amongst the groups (P > 0.05). CONCLUSION: Conservative access cavities did not offer any advantage in comparison with the traditional endodontic cavities in any of the parameters considered. Furthermore, conservative methods were associated with larger percentages of unprepared canal surface area and larger volumes of remaining root filling material within the pulp chamber.
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Cavidade Pulpar , Preparo de Canal Radicular , Dente Molar/diagnóstico por imagem , Dente Molar/cirurgia , Obturação do Canal Radicular , Microtomografia por Raio-XRESUMO
AIM: To evaluate the influence of the location and design of endodontic access cavities on root canal shaping and filling ability, pulp chamber cleaning and fracture resistance of extracted human mandibular incisors. METHODOLOGY: After pre-selection using periapical radiographs, forty extracted intact human mandibular incisors were scanned in a micro-computed tomographic device. The teeth were matched based on similar anatomical features of the canals and assigned to four experimental groups (n = 10) according to the endodontic access cavity and root canal preparation protocol: traditional/TRUShape (T/TRU); traditional/MTwo (T/MT); minimally invasive/TRUShape (MI/TRU); and minimally invasive/MTwo (MI/MT). The samples were scanned after root canal instrumentation and filling procedures. The parameters evaluated were as follows: volume and area of the root canal, noninstrumented canal areas, canal transportation and centring ratio, accumulated hard tissue debris, voids in root canal fillings and remnants of root canal filling materials in the pulp chamber. After root canal filling and cavity restoration procedures, the samples were submitted to a fracture resistance test. Data were statistically analysed using Shapiro-Wilk, one-way anova and Bonferroni tests with a significance level of 5% (α = 0.05). RESULTS: There was no difference regarding all parameters evaluated before and after root canal preparation (volume and area of the root canal, noninstrumented canal areas, canal transportation and centring ratio, and accumulated hard tissue debris) amongst the groups (P > 0.05). MI/TRU and MI/MT groups were associated with significantly more voids in root canal fillings when compared to the T/TRU and T/MT groups (P < 0.05). Percentage of root canal filling material remnants in the pulp chamber after cleaning procedures and mean fracture resistance values were not significantly different amongst the four experimental groups (P > 0.05). CONCLUSIONS: The location and design of the endodontic access cavity did not impact on root canal preparation nor resistance to fracture of extracted mandibular incisors, regardless of the instrument used. Minimally invasive access cavities were associated with significantly more voids in root canal fillings.
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Cavidade Pulpar , Incisivo , Cavidade Pulpar/diagnóstico por imagem , Humanos , Preparo de Canal Radicular , Tratamento do Canal Radicular , Microtomografia por Raio-XRESUMO
AIM: To evaluate the influence of ultraconservative endodontic access cavities (UEC) on gaps and void formation in resin composite restorations in extracted two-rooted maxillary premolars after root canal treatment. Traditional endodontic access cavities (TEC) were used as a reference for comparison. METHODOLOGY: Two-rooted maxillary premolars were scanned in a micro-computed tomographic (micro-CT) device, matched based on similar anatomical features and allocated into two groups (n = 10) according to the design of the access cavity: TEC or UEC. Teeth were mounted on a mannequin head and a single operator performed the treatment, including endodontic access cavity preparation, root canal detection, preparation, filling and restoration procedures, under magnification. For restorative procedure, a bulk fill flowable layer was applied initially followed by an overlaying of regular composite. After restoration procedures, a new micro-CT scan was performed to check the quality of the coronal restoration by analysing the percentage volume of empty spaces present in the tooth-restoration interface (gaps) and inside the restoration (voids). Data were analysed statistically using Shapiro-Wilk and Student's t tests with a significance level of 5%. RESULTS: All specimens had gaps and voids. There were significant differences between the access cavity designs regarding the formation of voids with significantly more voids associated with the UEC (P < 0.05). Gap formation did not differ between groups (P > 0.05). CONCLUSION: The access cavity design used during root canal treatment interfered with the adaptation of the restorative material. The minimally invasive access cavity design was associated with a significantly greater number of voids within restorations.
Assuntos
Resinas Compostas , Cavidade Pulpar , Dente Pré-Molar , Preparo da Cavidade Dentária , Restauração Dentária Permanente , Humanos , Tratamento do Canal RadicularRESUMO
AIM: To evaluate the response measures in continuing an image-guided intervention service in two tertiary-level musculoskeletal oncology centres during the COVID-19 pandemic. MATERIALS AND METHODS: This study was a retrospective review of all patients undergoing image-guided intervention in the computed tomography (CT) and normal ultrasound (US) rooms from 24 March 2020 to 24 May 2020 (during the COVID-19 pandemic peak) at Royal National Orthopaedic Hospital, London, and Royal Orthopaedic Hospital, Birmingham, UK. Measures were put in place to address air pressures, airflow direction, aerosol generation, and the safe utilisation of existing scanning rooms and work lists for interventional procedures. RESULTS: Three hundred and thirty-one patients (164 at Royal National Orthopaedic Hospital and 167 at Royal Orthopaedic Hospital) underwent image-guided procedures at both sites in the CT and US rooms. At the Royal National Orthopaedic Hospital, 40% of all procedures were performed under general anaesthesia. These consisted of 47 CT biopsies, 7 CT radiofrequency ablations (RFAs), and 12 US biopsies. At the Royal Orthopaedic Hospital, 86% of all procedures were performed under local anaesthetic, with no general anaesthetic procedures. These consisted of 61 CT biopsies and 83 US biopsies. All 256 patients having procedures in the CT room had no post-procedural complications or COVID-19-related symptoms and morbidity on follow-up. CONCLUSION: By adopting a pragmatic approach with meticulous planning, a limited, but fully functional image-guided interventional list can be run without any adverse patient outcomes.
Assuntos
Infecções por Coronavirus/prevenção & controle , Sistema Musculoesquelético/diagnóstico por imagem , Neoplasias/patologia , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Radiografia Intervencionista/estatística & dados numéricos , Tomografia Computadorizada por Raios X/estatística & dados numéricos , Ultrassonografia de Intervenção/estatística & dados numéricos , Biópsia , COVID-19 , Protocolos Clínicos , Arquitetura Hospitalar , Humanos , Sistema Musculoesquelético/patologia , Neoplasias/diagnóstico por imagem , Equipamento de Proteção Individual , Estudos Retrospectivos , Reino UnidoRESUMO
In the last decade, several access cavity designs involveing minimal removal of tooth tissue have been described for gaining entry to pulp chambers during root canal treatment. The premise behind this concept assumes that maximum preservation of as much of the pulp chamber roof as possible during access preparation would maintain the fracture resistance of teeth following root canal treatment. However, the smaller the access cavity, the more difficult it may be to visualize and debride the pulp chamber as well as locate, shape, clean and fill the canals. At the same time, a small access cavity may increase the risk of iatrogenic complications as a result of poor visibility, which may have an impact on treatment outcome. This study aimed to critically analyse the literature on minimal access cavity preparations, propose new nomenclature based on self-explanatory abbreviations and highlight the areas in which more research is required. The search was conducted without restrictions using specifics terms and descriptors in four databases. A complementary screening of the references within the selected studies, as well as a manual search in the highest impact journals in endodontics, namely International Endodontic Journal and Journal of Endodontics, was also performed. The initial search retrieved 1831 publications. The titles and abstracts of these papers were reviewed, and the full text of 94 studies was assessed. Finally, a total of 28 studies were identified as evaluating the influence of minimally invasive access cavity designs on the fracture resistance of teeth and on the different stages of root canal treatment (orifice location, canal shaping, canal cleaning, canal filling and retreatment). Overall, the studies had major methodological drawbacks and reported inadequate and/or inconclusive results on the utility of minimally invasive access preparations. Furthermore, they offered limited scientific evidence to support the use of minimally invasive access cavities to improve the outcome of root canal treatment and retreatment; they also provided little evidence that they preserved the fracture resistance of root filled teeth to a greater extent than traditional access cavity preparations. It was concluded that at present, there is a lack of supporting evidence for the introduction of minimally invasive access cavity preparation into routine clinical practice and/or training of undergraduate and postgraduate students.
Assuntos
Endodontia , Preparo de Canal Radicular , Preparo da Cavidade Dentária , Cavidade Pulpar , Humanos , Tratamento do Canal RadicularRESUMO
AIM: To investigate a potential cause-effect relationship between dentinal microcracks and fracture resistance of mandibular incisors that had not been endodontically treated. METHODOLOGY: Sixty mandibular incisors with circular-shaped canals were selected based on micro-computed tomographic scans to create a homogeneous sample. The cross-sectional images of the specimens were screened to identify and quantify the presence of dentinal microcracks. Then, teeth were embedded in polystyrene resin and subjected to axial compressive loading using a universal testing machine. After fracture, the roots were re-scanned and fractography analysis was performed by inspection of 3D models to verify crack propagation. Spearman's rank correlation was used to assess the correlation between the number of microcracks and force required to fracture. RESULTS: Dentinal microcracks were detected in 79% of the specimens (n = 44). The incidence of microcracks varied between teeth from 6% to 42% of the total slices per sample (average of 14 ± 17%). The number of microcracks per sample varied from 0 to 1605, with an average of 412 ± 484 (median = 221 and IQR 25% = 15/75% = 658). The load at failure values varied from 227 to 924 N, with an average of 560.3 ± 168.1 N (median = 561 and IQR 25% = 458/75% = 694). The Spearman correlation coefficient (rho) equalled 0.065. CONCLUSIONS: There was no cause-effect relationship between the number of dentinal microcracks and the fracture resistance of nonendodontically treated mandibular incisors. The presence and quantity of microcracks did not make these roots more prone to fracture.