Daniele Cavalcante
@uff.br
Odontoclínica
Universidade Federal Fluminense
Holds a degree in Dentistry from the Fluminense Federal University (1992) and a master's degree in Dental Clinic from the same university (2006). She holds a master's degree in Contemporary Artistic Processes from the Institute of Contemporary Art and Culture of the State University of Rio de Janeiro (2017) and is a doctoral student in the field of Art, City and Culture at the same institution. She has a PhD in Dental Clinic from Universidade Federal Fluminense (2018). She is an adjunct professor 2 at Universidade Federal Fluminense (UFF) and editor of Revista Concinnitas at the institute of arts at the University of the State of Rio de Janeiro (UERJ).
RESEARCH INTERESTS
Endodontics
Occlusion
Implants
FUTURE PROJECTS
Bite force assessment before and after Endodontically Treated Teeth
Decreased sensitivity to occlusal load could lead to a greater risk of damage to endodontically treated teeth. In dental research, bite force has been recorded as a variable to assess the efficacy of various dental procedures.Objective: To evaluate the impact of endodontic treatment on the proprioception and consequently on masticatory system.
Applications Invited
Scopus Publications
Scopus Publications
Diogo Moreira Rodrigues, Luisa Schubach da Costa Barreto, Rodrigo Lima Petersen, Vinicius Ferreira, Daniele Moreira Cavalcante, and Eliane dos Santos Porto Barboza
Elsevier BV
Gustavo De‐Deus, Gustavo O. Santos, Iara Zamboni Monteiro, Daniele M. Cavalcante, Marco Simões‐Carvalho, Felipe G. Belladonna, Emmanuel J. N. L. Silva, Erick M. Souza, Raphael Licha, Carla Zogheib,et al.
Wiley
AIM
To assess the interfacial adaptation (gap-containing areas) of two root canal sealers (EndoSequence BC Sealer and AH Plus) to a conventional gutta-percha (GP) cone (GP-sealer interface) in oval-shaped canals filled using the single cone technique.
METHODOLOGY
Sixteen teeth with oval-shaped canals were selected, scanned in a micro-computed tomographic device, and pair-matched according to the volume, aspect ratio and configuration of root canals. Root canals were then sequentially prepared with WaveOne Gold Primary and Large instruments, followed by filling with WaveOne Large GP points associated with either the premixed calcium-silicate EndoSequence BC Sealer or the epoxy resin-based AH Plus sealer (n = 8 per group) using the single cone technique. After 7 days stored in phosphate-buffered saline solution at 37 ºC, the specimens were rescanned and the reconstructed images segmented in order to differentiate the filling materials (sealer and GP cone) to the dentine. A total of 453 cross-sectional slices were assessed and categorized according to the presence or absence of gaps at the GP-sealer interface. Mann-Whitney U test verified differences between groups and were considered significant at alpha = 5%.
RESULTS
Gaps were non-homogenously distributed in two-dimensional axial cross-section images and none of the specimens showed completely gap-free areas along the entire GP-sealer interface. Root canals filled with EndoSequence BC Sealer and AH Plus displayed 171 (37.75%) and 136 (30.02%) slices with gaps in the GP-sealer interface and these frequencies were statistically significant (P = 0.000).
CONCLUSIONS
Although none of the specimens had a gap-free along the entire GP-sealer interface, oval canals filled with AH Plus showed less gaps than the ones filled with EndoSequence BC Sealer.
Emmanuel João Nogueira Leal Silva, Gustavo De‐Deus, Erick Miranda Souza, Felipe Gonçalves Belladonna, Daniele Moreira Cavalcante, Marco Simões‐Carvalho, and Marco Aurélio Versiani
Wiley
In the last decades, the move of Medicine towards minimally invasive treatments is notorious and scientifically grounded. As Dentistry naturally follows its footsteps, minimal access preparation also became a trend topic in the endodontic field. This procedure aims to maximize preservation of dentine tissue, backed up by the idea that this is an effective way to reduce the incidence of post-treatment tooth fracture. However, with the assessment of the body of evidence on this topic, it is possible to observe some key-points (a) the demand for nomenclature standardization, (b) the requirement of specific tools such as ultra-flexible instruments, visual magnification, superior illumination, and three-dimensional imaging technology, (c) minimally invasive treatment does not seem to affect orifice location and mechanical preparation when using adequate armamentarium, but it (d) may impair adequate canal cleaning, disinfection, and filling procedures, and also (e) it displays contradictory results regarding the ability to increase the tooth strengthen compared to the traditional access cavity. In spite of that, it is undeniable that methodological flaws of some benchtop studies using extracted teeth may be responsible for the conflicting data, thus triggering the need for more sophisticated devices/facilities and specifically designed research in an attempt to make it clear the role of the access size/design on long-term teeth survival. Moreover, it is inevitable that a clinical approach like minimal endodontic access cavities that demands complex tools and skilled and experienced operators bring to the fore doubts on its educational impact mainly when confronted with the conflicting scientific output, ultimately provoking a cost-benefit analysis of its implementation as a routine technique. In addition, this review discusses the ongoing scientific and clinical status of minimally invasive access cavities aiming to input an in-depth and unbiased view over the rationale behind them, uncovering not only the related conceptual and scientific flaws, but also outlining future directions for research and clinical practices. The conclusions attempt to skip from passionate disputes highlighting the current body of evidence as weak and incomplete to guide decision making, demanding the development of a close-to-in-situ laboratory model or a large and well-controlled clinical trial to solve this matter.
Gustavo De‐Deus, Erick Miranda Souza, Emmanuel João Nogueira Leal Silva, Felipe Gonçalves Belladonna, Marco Simões‐Carvalho, Daniele Moreira Cavalcante, and Marco Aurélio Versiani
Wiley
Canal filling materials and techniques have been one of the most studied topics in Endodontics. A simple search using the mesh term "root canal filling" in PubMed revealed more than 11,000 articles, an impressive number that is much higher than "root canal disinfection" (5,544 articles) or even the popular "root canal preparation" (8,527 articles). The overriding importance attributed to root filling procedures is not merely intuitive. It derived from the appealing relevance given by the appearance of the white lines in common radiographs grounded on retrospective clinical data that had identified the quality of a root filling as one of the major causes of treatment failure (lack of healing). Since the publication of the Washington study, impressive efforts have been made for the release of new materials and techniques, as well as, for the development of a plethora of laboratory methods to assess the quality of root filling procedures. This narrative review aims to address and discuss the most relevant laboratory methods to assess the root canal filling. Since filling quality improvements have not translated into higher success rates, as reported in longitudinal clinical studies, more than to deliver a simple methodology-based review, this paper aims to present an in-depth critical view on the assessment of laboratory methods used to study the filling materials and techniques. Recent data indicate that the long-term dimensional stability/degradation over time of endodontic sealers plays a central role in the treatment outcome. In this context, laboratory methods should be developed focusing on predicting, at least to some degree, the long-term clinical behaviour of root canal fillings, rather than simply ranking different materials or techniques.
Marco Aurélio Versiani, Daniele Moreira Cavalcante, Felipe Gonçalves Belladonna, Emmanuel João Nogueira Leal Silva, Erick Miranda Souza, and Gustavo De‐Deus
Wiley
The purpose of this narrative review is to discuss the scientific milestones that led to the current understanding of the root dentinal microcrack phenomenon based on the interplay between the usage of micro-computed tomography (micro-CT) as an analytical tool alongside a close-to-mouth experimental model. In 2009, reports on the development of dentinal microcracks in extracted teeth after root canal preparation triggered an awareness of the potential for vertical root fractures (VRFs) of endodontically treated teeth could be developed from defects created by the mechanical stress of nickel-titanium preparation systems on dentine. This assumption was taken for granted, even though no cause-effect relationship had been scientifically demonstrated. Since then, several studies using the sectioning method with extracted teeth have been published and the large discrepancy among their outcomes soon become evident. Moreover, the high frequency of reported dentinal microcracks largely contrasted with the clinical incidence of VRFs, raising doubts on their methodological reliability. Using micro-CT technology, it was demonstrated by several studies that, in extracted teeth, dentinal defects already existed before the endodontic procedures, indicating that the initial reports framed a non-existing cause-effect relationship between canal preparation and dentinal microcracks. Although these new findings contributed to a better comprehension of this phenomenon, the misconception that microcracks were the starting point for VRFs was only surpassed with a new in situ approach using fresh cadavers. Surprisingly, microcracks were not identified in sound teeth. As a conclusion, dentinal microcracks in extracted teeth are considered a non-natural occurrence observed only in a laboratory setup as a consequence of dehydration and storage conditions. Thus, dentinal microcracks shall not be considered as the starting point for VRFs as they do not manifest in non-extracted teeth. Identifying dentinal microcracks as a laboratory phenomenon highlights the impact of recent scientific developments to disclaim the clinical relevance of laboratory-obtained outcomes.
Gustavo De‐Deus, Diogo S. Oliveira, Daniele M. Cavalcante, Marco Simões‐Carvalho, Felipe G. Belladonna, Leandro S. Antunes, Erick M. Souza, Emmanuel J. N. L. Silva, and Marco A. Versiani
Wiley
AIM
To compare the bond strength of an epoxy resin-based sealer and two calcium silicate-based sealers (CSS) to gutta-percha disks using a new method.
METHODOLOGY
Round disks of gutta-percha (n = 60), measuring 10 mm in diameter and 2 mm in thickness, were placed on a glass plate and a drop of each sealer (AH Plus, EndoSequence BC Sealer and EndoSeal MTA) was placed on their surface. Another identical disk was placed onto the first one and a standardized weight (0.0981 N) applied over them using a special developed apparatus. Ten samples prepared for each sealer were submitted to a microshear bond strength test accomplished by a specially designed setup coupled to a universal testing machine. The Kruskal-Wallis test followed by a post hoc procedure was used to compare groups considering the preliminary analysis of the raw data that indicated the non-adherence to a Gaussian distribution (Shapiro-Wilk, p < 0.05). Alpha-error was set at 5%.
RESULTS
Overall, no premature failure occurred. All sealers had some degree of adhesiveness to gutta-percha disks but with a significant difference among them (Kruskal-Wallis, p = 0.019). The epoxy resin-based sealer (AH Plus) had significantly higher median shear bond strength values (1.43 MPa; 1.40-1.83) compared to Endoseal MTA (0.53 MPa; 0.46-0.73) (p = 0.021) and Endosequence BC Sealer (0.45 MPa; 0.34-0.46) (p = 0.023) while the lowest median value was observed with Endosequence BC Sealer (0.45 MPa; 0.34-0.46) (p < 0.05).
CONCLUSIONS
CSS sealers had weaker bonding to gutta-percha when compared to the epoxy resin-based AH Plus sealer. The proposed methodology is an innovative and reproducible method for testing the bond strength of root canal sealers to gutta-percha.
Felipe Gonçalves Belladonna, Lorrany Larisse Costa Rodrigues, Alex Sandro Mendonça Leal, Henrique Eduardo Oliveira, Ana Carolina de Carvalho Maciel, Daniele Moreira Cavalcante, Emmanuel João Nogueira Leal Silva, Érica Martins Valois, Erick Miranda Souza, and Gustavo De‐Deus
Wiley
AIM
To assess the impact of mechanical overinstrumentation of root canals in extracted teeth on the development of dentinal microcracks in the apical portion of the root by means of micro-computed tomographic (micro-CT) analysis. Root canal preparation short of the canal terminus and at the apical foramen (AF) were used as controls.
METHODOLOGY
Twenty 2-rooted maxillary premolars with two canals were selected, scanned in a micro-CT device and the root canals prepared sequentially using Reciproc M-Wire R25 instruments to working lengths: 1 mm short of the AF (AF - 1 mm), at the AF (AF), and overinstrumentation (AF + 1 mm). A micro-CT scan of each specimen was performed after each time-point. After reconstruction and co-registration procedures, the images were screened from the cementoenamel junction to the apex (n = 55,352) to identify the presence of dentinal microcracks in the apical third of the root.
RESULTS
After the analyses of 55,352 slices, dentinal microcracks were visualized in 12.45% of the images (6,892 slices), with 5.73% (3,174 slices) in the cervical, 3.57% (1,976 slices) in the middle and 3.15% (1,740 slices) in the apical third. All dentinal microcracks observed at all time-points (AF - 1 mm, AF and AF + 1 mm) were already present in the corresponding images before canal instrumentation. Therefore, no new microcracks were detected, regardless of the working length used for canal instrumentation.
CONCLUSION
Reciprocating root canal preparation either short, at or beyond the AF (overinstrumentation) did not create dentinal microcracksin the roots of extracted 2-rooted maxillary premolars in the roots of extracted 2-rooted maxillary premolars.
Gustavo De-Deus, Evaldo Almeida Rodrigues, Jong-Ki Lee, J. Kim, Emmanuel João Nogueira Leal da Silva, Felipe Gonçalves Belladonna, Daniele Moreira Cavalcante, Marco Simões-Carvalho, Diogo da Silva Oliveira, Marco Aurélio Versiani,et al.
Springer Science and Business Media LLC
Emmanuel João Nogueira Leal Silva, Iracema C. Ehrhardt, Gerhilde Callou Sampaio, Milla Lessa Cardoso, Diogo da Silva Oliveira, Marcelo J. Uzeda, Monica Diuana Calasans-Maia, Daniele Moreira Cavalcante, Mario Luis Zuolo, and Gustavo De-Deus
Springer Science and Business Media LLC
G. De‐Deus, F. G. Belladonna, D. M. Cavalcante, M. Simões‐Carvalho, E. J. N. L. Silva, J. C. A. Carvalhal, R. Q. Zamolyi, R. T. Lopes, M. A. Versiani, P. M. H. Dummer,et al.
Wiley
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 series of 1:1 dilutions 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 oxidizing ability 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 pulp tissue dissolution was recorded. For the last experiments (histological validation and micro-CT assessment), 8 extracted mandibular premolars with 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, 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 qualitatively 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. 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 pulp tissue dissolution capability. The pulp tissue impregnation protocol using Lugol allowed the visualization of pulp tissue on micro-CT images and the identification of remaining pulp tissues during the evaluation of chemical-mechanical canal procedures.
Edson Jorge Lima MOREIRA, Henrique dos Santos ANTUNES, Victor Talarico Leal VIEIRA, Daniele Moreira CAVALCANTE, Henrique Eduardo OLIVEIRA, Diogo da Silva OLIVEIRA, Gustavo DE-DEUS, and Emmanuel João Nogueira Leal da SILVA
FapUNIFESP (SciELO)
The aim of the present study was to evaluate the cyclic fatigue, torsional resistance and surface roughness of Reciproc R25 instruments in four different situations, namely as new instruments and as instruments tested after clinical preparation of one, two or three maxillary molars with four root canals. The total time required to perform each root canal preparation was recorded. Cyclic fatigue resistance was determined by the time to fracture using a customized testing device (n = 10 per group). The torsional test evaluated the torque and angle of rotation to failure according to ISO 3630-1 (n = 10 per group). The roughness of the working parts of new and used instruments was evaluated with a profilometer (n = 5 per group). Statistical analysis was performed using one-way ANOVA and Tukey's test. The level of significance was set at 5%. No fractures or deformations were observed after clinical use. Higher preparation time was needed during the third use of the instruments for all root canals (p < 0.05). There were no significant differences among the groups in regard to either cyclic fatigue or torsional resistance (p > 0.05). Regarding the roughness measurements, groove depth was higher on new and one- versus two- or three-maxillary-molar-prepared instruments (p < 0.05). It can be concluded that the clinical use of Reciproc instruments increased preparation time and decreased surface roughness. However, clinical use did not affect the cyclic fatigue or torsional resistance of the Reciproc instruments.
Gustavo De-Deus, Milla Lessa Cardoso, Marco Simões-Carvalho, Emmanuel J.N.L. Silva, Felipe Gonçalves Belladonna, Daniele Moreira Cavalcante, Diogo da Silva Oliveira, Erick Miranda Souza, Ricardo Tadeu Lopes, and Marco Aurélio Versiani
Elsevier BV
D. M. Cavalcante, F. G. Belladonna, M. Simões‐Carvalho, J. C. A. Carvalhal, E. M. Souza, R. T. Lopes, E. J. N. L. Silva, P. M. H. Dummer, and G. De‐Deus
Wiley
AIM
This study aimed to investigate a potential cause-effect relationship between dentinal microcracks and fracture resistance of lower 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-section 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 227N to 924N, with an average of 560.3 ± 168.1N (median = 561 and IQR 25% = 458 / 75% = 694). The Spearman correlation coefficient (rho) equaled 0.065.
CONCLUSIONS
There is no cause-effect relationship between the amount of dentinal microcracks and the fracture resistance of nonendodontically treated lower incisors. The presence and quantity of microcracks did not turn these roots more prone to fracture.
G. De‐Deus, M. Simões‐Carvalho, F. G. Belladonna, M. A. Versiani, E. J. N. L. Silva, D. M. Cavalcante, E. M. Souza, G. F. Johnsen, H. J. Haugen, and S. Paciornik
Wiley
AIM
To introduce a new method to select anatomically matched teeth using micro-computed tomographic (micro-CT) technology.
METHODOLOGY
Single-rooted mandibular incisors with a single root canal (n = 60) were selected and distributed into three experimental groups according to the method used for matching 10 pairs of teeth in each group. In group 1, the pairs of mandibular incisors were randomly selected from a pool of teeth. In group 2, teeth were paired based on the measurement of canal width 5 mm from the root apex using radiographs taken from buccolingual and mesiodistal directions. In group 3, teeth were scanned (pixel size of 14.25 μm) and pair-matched based on the anatomical aspects of the root canal, named aspect ratio (AR), volume and three-dimensional canal geometry. After allocating the specimens into groups 1 and 2, the teeth were scanned and the canal morphology evaluated as in group 3. A bivariate Pearson's regression analysis was performed correlating the individual AR values of each pair and the correlation coefficient was used to estimate the strength of the pair-matching process. One-way ANOVA post hoc Tukey tests were applied for pair-wise comparisons at a significance level of 5%.
RESULTS
The micro-CT revealed that 100% of the samples had strong (80%) or very strong (20%) correlations with respect to AR values. Analysis of the radiographic method revealed strong correlation in two pairs (20%), but most of the samples had weak (30%) or negligible (30%) correlation coefficients. The randomization method resulted in 3 pairs (30%) with very strong correlations, while 50% had weak or neglectable rates. A significant difference in correlation coefficients was observed in the micro-CT method compared to the other groups (p < 0.05), whilst no difference was detected between radiographic and randomized methods (p > 0.05). Eta squared (η2 ) calculations demonstrated a very high effect size in the micro-CT group for selecting pairs (0.99), and lower effect sizes in the radiographic (0.67) and randomized (0.66) groups.
CONCLUSIONS
Micro-CT method was able to provide better control of the confounding effect that anatomical variances in tooth morphology may have on the results in experiments with matched-pair design.
F. N. Arashiro, G. De‐Deus, F. G. Belladonna, D. M. Cavalcante, M. S. Coelho, E. J. N. L. Silva, K. F. S. Pereira, P. G. Silva, R. T. Lopes, and E. M. Souza
Wiley
AIM
To evaluate the incidence of root dentinal microcracks after two extraction techniques through micro-computed tomographic (micro-CT) analysis.
METHODOLOGY
Thirty pairs of premolars, extracted for orthodontic reasons, were assigned to 2 experimental groups, following a split-mouth design (n = 30): traumatic technique group (TTG) - teeth extracted following a conventional protocol using forceps, and atraumatic technique group (ATG) - teeth extracted following an atraumatic technique protocol in which the root was gently detached from the periodontal ligament using a periotome. All teeth were immediately immersed in distilled water and scanned in a micro-CT device within 72 hours following the extraction. The assessment of the images was done on cross-section images by 2 masked evaluators. The Mann-Whitney test was used to assess the significant differences between the groups regarding the number of cross-sections displaying microcracks while Fischer's exact test was used to assess differences in the frequency of specimens with defects (P<0.05).
RESULTS
A total of 52,750 micro-CT cross-sectional images were evaluated. A total of 352 cross-sections had at least one dentinal defect. Microcracks were observed in 5 teeth of the TTG group (n = 352 slices) and in 2 teeth of the ATG group (n=103 slices). The statistical analysis used was unable to detect a significant difference between the groups in terms of the number of dentinal microcracks (P=0.233) and in the frequency of teeth displaying microcracks (P=0.424).
CONCLUSION
A small number of sound teeth without endodontic treatment had dentinal microcracks regardless of the extraction technique applied. No difference was noticed between the traumatic or atraumatic techniques in the incidence of microcracks.
G. De‐Deus, M. Simões‐Carvalho, F. G. Belladonna, D. M. Cavalcante, L. S. Portugal, C. G. Prado, E. M. Souza, R. T. Lopes, and E. J. N. L. Silva
Wiley
AIM
To investigate the shaping and cleaning performance of the Clearsonic ultrasonic tip as a supplementary tool during the preparation of long oval-shaped root canals through micro-computed tomographic (micro-CT) imaging technology. Reciproc M-Wire R40 instrument was used as a reference instrumentation technique for comparison.
METHODOLOGY
Twenty mandibular incisors with a single, straight and long oval-shaped canal were selected and pair-matched by micro-CT scanning. The root canals were prepared with Reciproc R25 and R40 instruments, scanned again in a micro-CT device and randomly allocated into one of the two experimental groups (n = 10), according to the supplementary debridement protocol used: Clearsonic or Reciproc R40 used in brushing motion against buccal and lingual walls. Non-instrumented canal areas, accumulation of hard-tissue debris (AHTD) and volume of removed dentine were assessed using micro-CT imaging after supplementary debridement protocols. Data were analyzed statistically in two phases using t-test with a significance level of 5%.
RESULTS
In phase-1, there was significant similarity between the samples regarding the evaluated micro-CT baseline parameters (P > 0.05), validating their anatomical similarity between the pairs. In phase-2, there was significant difference between the groups for canal volume, surface area, non-instrumented root canal walls and the amount of removed dentine for both absolute and percentage values (P < 0.05), but not AHTD (P = 0.759).
CONCLUSIONS
The Clearsonic tip out-performed the Reciproc R40 instrument as a supplementary debridement protocol as it was associated with significantly greater reduction of non-instrumented root canals walls and consequently a larger amount of removed dentine. Both groups performed similarly regarding accumulated hard-tissue debris.
Gustavo De-Deus, Emmanuel J. N. L. Silva, Jorge N. R. Martins, Daniele Cavalcante, Felipe G. Belladonna, and Gianluca Plotino
Springer International Publishing
G. De‐Deus, D. M. Cavalcante, F. G. Belladonna, J. Carvalhal, E. M. Souza, R. T. Lopes, M. A. Versiani, E. J. N. L. Silva, and P. M. H. Dummer
Wiley
G. De‐Deus, E. A. Rodrigues, F. G. Belladonna, M. Simões‐Carvalho, D. M. Cavalcante, D. S. Oliveira, E. M. Souza, K. A. Giorgi, M. A. Versiani, R. T. Lopes,et al.
Wiley
AIM
To investigate the smallest dentine thickness in mesial canals of mandibular molars along the cervical and middle thirds of the root by means of a micro-computed tomographic (micro-CT) technology and digital image analysis.
METHODOLOGY
Fifty mesial roots of mandibular molars having two independent canals (mesiobuccal and mesiolingual), in the coronal and middle levels, were selected and scanned in a micro-CT device. After reconstruction procedures, approximately 468 slices per root covering the 7 mm below the furcation area of the mesial root were analysed to measure the smallest dentine thickness (danger zone [DZ]) in each slice from both distal and mesial regions of the mesial canals by an automatic segmentation process.
RESULTS
The DZ values in the mesiobuccal canals varied from 0.67 to 1.93 mm, with an average of 1.13 ± 0.21 mm. For the mesiolingual canals, the DZ varied from 0.77 to 1.89 mm with an average of 1.10 ± 0.21 mm. There was no correspondence in the DZ between the mesiobuccal and mesiolingual canals at the same cross-sectional level in 71% of the specimens. Moreover, the smallest dentine thickness was towards the mesial region of the roots in 22% and 18% of the mesiolingual and mesiobuccal canals, respectively. (Figs 1 and 2 CONCLUSIONS: The smallest dentine thickness was on the mesial plane of the roots in about 40% of the canals. The vertical location of the DZ in relation to the furcation area was in the middle third of the root.
Gustavo De-Deus, Felipe Gonçalves Belladonna, Arthur de Siqueira Zuolo, Daniele Moreira Cavalcante, Marco Simões Carvalho, Alessandra Marinho, Erick Miranda Souza, Ricardo Tadeu Lopes, and Emmanuel João Nogueira Leal Silva
Elsevier BV
Emmanuel João Nogueira Leal Silva, Antonio Canabarro, Márcia Rejane Thomas Canabarro Andrade, Daniele Moreira Cavalcante, Oscar Von Stetten, Tatiana Kelly da Silva Fidalgo, and Gustavo De-Deus
Elsevier BV
G. De‐Deus, F. G. Belladonna, A. S. Zuolo, D. M. Cavalcante, J. C. A. Carvalhal, M. Simões‐Carvalho, E. M. Souza, R. T. Lopes, and E. J. N. L. Silva
Wiley
AIM
To evaluate the performance of XP-endo Finisher R instruments when removing root filling remnants from oval-shaped canals using microcomputed tomographic (micro-CT) imaging as the analytical tool. Passive ultrasonic irrigation (PUI) was used as a reference technique for comparison.
METHODOLOGY
Twenty mandibular incisors with oval-shaped canals were matched based on similar anatomic features of the canal (volume, aspect ratio and 3D configuration) after scanning procedures. The canals were prepared with Reciproc R25 instruments, filled with gutta-percha and AH Plus sealer using the single-cone technique and retreated up to a Reciproc R40 instrument. After retreatment procedures, the specimens were rescanned, and the homogeneity between the specimens, the oval-shaped anatomy and the remaining filling material were confirmed. The pair-matched samples were assigned to two experimental groups (n = 10), according to the supplementary approach used: XP-endo Finisher R or PUI. Each sample was scanned after each endodontic procedure. The volume of remaining root filling material was quantified before and after the use of each supplementary approach. This analysis was performed considering the total canal (Student t-test) and also by thirds (anova procedure followed by a Bonferroni correction). Data were analysed statistically with a significance level of 5%.
RESULTS
The volume of root filling material at baseline was similar between the groups (t-test, P = 0.787). XP-endo Finisher R removed significantly more root filling material compared to PUI (t-test, P = 0.015), as it removed a mean of ≅32% material compared to 12% for the PUI. There was no difference in the amount of root filling material removed in the root canal thirds after using both supplementary approaches (one-way anova, P = 0.07 for XP-endo Finisher R and P = 0.886 for PUI).
CONCLUSIONS
Both supplementary approaches significantly reduced the volume of remaining root filling material from oval-shaped canals. The XP-endo Finisher R instrument removed significantly more root filling material than PUI. None of the supplementary approaches was able to render oval-shaped canals completely free from remaining root filling material.
C. B. Santos, M. Simões‐Carvalho, R. Perez, V. T. L. Vieira, H. S. Antunes, D. F. Cavalcante, G. De‐Deus, and E. J. N. L. Silva
Wiley
AIM
To evaluate the torsional properties of the NiTi glide path reciprocating instruments R-Pilot (VDW, Munich, Germany) and WaveOne Gold Glider (Dentsply Sirona, Ballaigues, Switzerland).
METHODOLOGY
Ten R-Pilot (size 12.5, .04 taper) and 10 WaveOne Gold Glider (size 15, .02v taper) instruments were used. The torque and angle of rotation at failure of new instruments (n = 10) were measured according to ISO 3630-1. Three millimetres of each instrument tip was clamped to a small load cell by a lever arm linked to the torsion axis. The fracture surface of all fragments was examined with a scanning electron microscope. Data were analysed using the Student t-test at a significance level of P < 0.05.
RESULTS
The maximum torsional strength of the R-Pilot instruments was greater than the WaveOne Gold Glider (P < 0.05). In contrast, WaveOne Gold Glider instruments had significantly higher angular rotation to fracture than R-Pilot instruments (P < 0.05). The scanning electron microscopy of the fracture surfaces revealed similar and typical features of torsional failure (ductile type) for both brands. The torsional failure displayed two zones: the first with microvoids in the centre of the instruments (core) and the second one represented by plastic deformation around the microvoids; this configuration occurred because of the shear stresses originated during the twisting.
CONCLUSIONS
R-Pilot instruments had a lower angle of rotation to fracture but a higher torque to failure than WaveOne Gold Glider instruments.
G. De‐Deus, D. M. Cavalcante, F. G. Belladonna, J. Carvalhal, E. M. Souza, R. T. Lopes, M. A. Versiani, E. J. N. L. Silva, and P. M. H. Dummer
Wiley
AIM
To investigate the prevalence, location and pattern of pre-existing microcracks in non-endodontically treated teeth from fresh cadavers. Micro-computed tomography (micro-CT) technology was used as the analytical tool enabling full screening of the root dentine with the teeth retained in their original alveolar socket.
METHODOLOGY
As a pilot study and to validate the present method, a series of 4 high-resolution scans were performed on one bone-block specimen with teeth collected post-mortem: (i) entire bone-block including the teeth, (ii) second molar tooth extracted atraumatically from the bone-block, (iii) extracted tooth dehydrated to induce dentinal defects and (iv) entire bone-block following reinsertion of the extracted tooth into its matching alveolar socket. In the main study, forty-two dentoalveolar maxillary and mandibular bone-blocks each containing 3-5 adjacent teeth (a total of 178 teeth) were collected post-mortem and scanned in a micro-CT device. All cross-section images of the 178 teeth (n = 65 530) were screened from the cementoenamel junction to the apex to identify the presence of dentinal defects.
RESULTS
In the pilot study, the microcracks observable when the dehydrated tooth was outside the bone-block remained detectable when the entire bone-block plus reinserted tooth was scanned. This means that the screening process revealed the presence of the same microcracks in both experimental situations (the tooth outside and inside the maxillary bone-block). From a total of 178 teeth in the bone-blocks removed from cadavers, 65 530 cross-sectional images were analysed and no dentinal microcracks were detected.
CONCLUSIONS
This in situ cadaveric model revealed the lack of pre-existing dentinal microcracks in non-endodontically treated teeth. Thus, the finding of dentinal microcracks observed in previous cross-sectional images of stored extracted teeth is unsound and not valid. It should be assumed that microcracks observed in stored extracted teeth subjected to root canal procedures are a result of the extraction process and/or the post-extraction storage conditions. Therefore, as a consequence, the presence of such dentinal microcracks in stored extracted teeth - observable in cross-sectional images of the roots - should be referred to as experimental dentinal microcracks.
G. De‐Deus, F. G. Belladonna, M. Simões‐Carvalho, D. M. Cavalcante, C. N. M. J. Ramalho, E. M. Souza, R. T. Lopes, and E. J. N. L. Silva
Wiley
AIM
To assess the shaping ability of the new XP-endo Shaper instrument after different working times.
METHODOLOGY
Ten mesial roots of mandibular molars were scanned in a micro-computed tomographic device and prepared using the XP-endo Shaper instrument up to the working length (WL) according to the manufacturer's recommendation. Then, each specimen was subjected to an extra 15, 30 and 45 s of active instrumentation at the WL. Postoperative scans were performed after canal preparation at each time-point. Then, the registered pre- and postoperative datasets were examined to evaluate the percentages of volume and surface area of the instrumented canal, surface area of noninstrumented canal areas and the volume of removed dentine. Repeated measures general linear model was used to compare the differences in either the increase or the reduction of the parameters amongst the time-points. Alpha-error was set at 5%.
RESULTS
Extending the period of XP-endo Shaper active instrumentation at WL significantly influenced several parameters such as volume (P < 0.001) and surface area (P < 0.001) of the instrumented canal, surface area of noninstrumented canal areas (P < 0.001), and volume of removed dentine (P < 0.001).
CONCLUSIONS
Extending the activation time of XP-endo Shaper instruments at WL resulted in a more comprehensive root canal preparation, increasing the volume and surface area of root canal preparation and the volume of removed dentine.
RECENT SCHOLAR PUBLICATIONS
Publications
Root dentinal microcracks: a post‐extraction experimental phenomenon?