Papers by Daniele Moreira Cavalcante
A critical analysis of research methods and experimental models to study dentinal microcracks
International Endodontic Journal, Nov 27, 2021
The purpose of this narrative review was to discuss the scientific milestones that led to the cur... more The purpose of this narrative review was 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 amongst 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 can be considered a non‐natural occurrence observed only in a laboratory set‐up 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.
Concinnitas, Dec 17, 2020
onde pesquisa "a poética da desaparição" e investiga os desdobramentos entre a experiência estéti... more onde pesquisa "a poética da desaparição" e investiga os desdobramentos entre a experiência estética/política e o aparecimento sensível da ideia, através da fotografia, do objeto e da pintura, sob orientação do prof. Dr. Alexandre Sá. Mestre pelo mesmo programa, participou de diversos editais e exposições como Depois do Futuro
Relationship between smile type and periodontal phenotype: A clinical and tomographic cross-sectional study
Journal of Dentistry
Micro‐CT assessment of gap‐containing areas along the gutta‐percha‐sealer interface in oval‐shaped canals
International Endodontic Journal
AIM To assess the interfacial adaptation (gap-containing areas) of two root canal sealers (EndoSe... more 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.
Present status and future directions – Minimal endodontic access cavities
International Endodontic Journal, 2022
In the last decades, the move of medicine towards minimally invasive treatments is notorious and ... more In the last decades, the move of medicine towards minimally invasive treatments is notorious and scientifically grounded. As dentistry naturally follows in its footsteps, minimal access preparation have also becume 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 contr...
Brazilian Oral Research, 2021
The aim of the present study was to evaluate the cyclic fatigue, torsional resistance and surface... more 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.
Is canal overinstrumentation able to produce apical root dentinal microcracks in extracted teeth?
International Endodontic Journal, 2021
AimTo assess the impact of mechanical overinstrumentation of root canals in extracted teeth on th... more AimTo 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.MethodologyTwenty 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.ResultsAfter the analyses of 55 352 slices, dentinal microcracks were visualized in ...
Journal of Endodontics, 2021
Clinical Oral Investigations, 2020
Objectives To present and explore the potential of an animal-based experimental model developed t... more Objectives To present and explore the potential of an animal-based experimental model developed to determine the set of root canal sealers in vivo. The setting of AH Plus, BioC Sealer, TotalFill BC Sealer, and Sealapex was determined using either ISO 6876 or the novel in vivo method proposed in this study. The in vitro setting time of the sealers tested was determined in accordance with ISO 6876:2012. In determining the in vivo set, 24 adult Wistar rats were followed up for two evaluation periods: 1 and 4 weeks. Their upper-right incisor was extracted, and its pulp tissue was removed. The root canal was then filled from retrograde with one of the 4 sealers, and the tooth was re-implanted and fixed with a layer of a flowable composite resin. After 1 or 4 weeks of the surgical procedures, the animals were euthanized, and their incisors were extracted. Two-mm-thick slices of the middle third of the tooth root were obtained and assessed with a Gillmore device, to determine whether or not the sealer had set. The following in vitro results were obtained by using ISO 6876 methodology: AH Plus set after a mean time of 423 ± 20 min and 476 ± 35 min, in metal and plaster molds, respectively. BioC Sealer set after 7 days (in dental plaster molds), whereas TotalFill BC Sealer and Sealapex did not set even after 25 days in both tested conditions (metal or dental plaster molds). Using the novel in vivo methodology, AH Plus, BioC Sealer, and TotalFill BC Sealer set after both 7 and 30 days. In contrast, Sealapex did not set at either time point. Conclusions AH Plus and BioC Sealer set under both in vitro and in vivo test conditions. TotalFill BC Sealer did not set under in vitro conditions but did after 1 week under in vivo conditions. Sealapex did not set under either in vitro or in vivo conditions. Clinical relevance The influence of the testing conditions on the setting results is a clear indication that new in vivo experimental models should be useful in future studies on Bioceramics root canal sealers. Keywords Calcium silicate cements . Mineral trioxide aggregate . Physicochemical properties . Root canal sealer . Setting time
Clinical Oral Investigations, 2020
International Endodontic Journal, 2020
AimTo introduce a new method to select anatomically matched teeth using micro‐computed tomographi... more AimTo introduce a new method to select anatomically matched teeth using micro‐computed tomographic (micro‐CT) technology.MethodologySingle‐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 va...
Journal of Evidence Based Dental Practice, 2019
The aim of the present systematic review was to evaluate if epoxy resinbased root canal sealers p... more The aim of the present systematic review was to evaluate if epoxy resinbased root canal sealers present a superior push-out bond strength than calcium silicatebased root canal sealers. The inclusion criteria consisted of in vitro studies that compared the pushout bond strength of epoxy resin-based and calcium silicate-based sealers. A systematic search was performed in the following databases until February 2018: PubMed, Science Direct, Scopus, Web of Science and Open Grey. The quality assessment and data extraction of the selected articles were performed. The meta-analysis of the pooled data and the subgroups according to the root thirds were carried out using the RevMan software (p<0.05). The search resulted in 2,292 studies. After the duplicated studies were removedand the title and abstract were read, 20 studies were selected and 17 were considered as having a low risk of bias. The pooled meta-analysis comparing epoxyresin based (n=467) and paste-to-paste calcium-silicatebased root canal sealers (n=467) demonstrated higher mean push-out bond strength values (p<0.001) for the epoxy-resin based, the heterogeneity among studies was 85% (I 2 ). The comparisons between epoxyresin based (n=358) and premixed ready-to-use calcium-silicate based root canal sealer (n=358) also demonstrated significant difference between the sealers (p<0.05) with an I 2 of 95%. The subgroup analysis showed that only in the middle third increased bond strength values for epoxy-resin based sealer was observed (p<0.001) with an I 2 of 94%. The epoxy-resin based sealer presented with a higher push-out bond strength in comparison with paste-to-paste calcium silicate-based root canal sealer regardless of the root third assessed. In addition, the epoxy-resin based sealer exhibited an increased push-out bond strength in comparison with premixed ready-to-use calcium-silicate based root canal sealer when evaluating the middle third.
International Endodontic Journal, 2018
AimTo investigate the prevalence, location and pattern of pre‐existing microcracks in non‐endodon... more AimTo 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.MethodologyAs 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 im...
International Endodontic Journal, 2018
AimTo evaluate the torsional properties of the NiTi glide path reciprocating instruments R‐Pilot ... more AimTo evaluate the torsional properties of the NiTi glide path reciprocating instruments R‐Pilot (VDW, Munich, Germany) and WaveOne Gold Glider (Dentsply Sirona, Ballaigues, Switzerland).MethodologyTen 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.ResultsThe 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 ...
Fixed Rehabilitation of Edentulous Mandibles Using 2 to 4 Implants
Implant Dentistry, 2016
This systematic review evaluated survival rates, marginal bone loss (MBL), and complications of u... more This systematic review evaluated survival rates, marginal bone loss (MBL), and complications of using 2 to 4 implants to support full-arch fixed prostheses in the mandible. An electronic search was performed in PubMed, Web of Science, and the Cochrane Central Register of Controlled Trials to identify relevant articles published until March 2015. Articles were critically reviewed to determine the level of quality. The initial search resulted in 910 articles from PubMed/MEDLINE, 162 titles from the Cochrane Central Register of Controlled Trials, and 363 from the Web of Science. After an initial assessment and careful reading, 19 studies published between 1999 and 2014 were included in this review. The results of this review suggest that full-arch fixed dental prosthesis in mandible supported by 2 to 4 implants exhibited a low rate of failures for implants and prostheses, a low rate of MBL, and a low rate of biomechanical and biological complications.
International Endodontic Journal, 2020
AimTo investigate a potential cause–effect relationship between dentinal microcracks and fracture... more AimTo investigate a potential cause–effect relationship between dentinal microcracks and fracture resistance of mandibular incisors that had not been endodontically treated.MethodologySixty 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.ResultsDentinal microcracks were detected in 79% of the specimens (n = 44). The incidence of microcracks varied between teeth from 6% to 42% of the total slice...
Anatomical danger zone reconsidered: a micro‐ CT study on dentine thickness in mandibular molars
International Endodontic Journal, 2019
AIM To investigate the smallest dentine thickness in mesial canals of mandibular molars along the... more 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.
Minimally Invasive Root Canal Instrumentation
Despite the passionate way that some defend that conventional canal mechanical instrumentation de... more Despite the passionate way that some defend that conventional canal mechanical instrumentation decreases the resistance of teeth to fracture, the current literature is composed by a limited amount of laboratory studies, which means low-quality evidence to shape and guide the clinical decision-making process. Therefore, the idea of providing optimum dimensions for root canal mechanical preparation is one current ongoing concern in endodontic practice and science. Considering the as yet unclear situation of the minimal invasive approaches and rationales proposed to render an endodontically treated tooth predictably functional, the present text focuses on the optimal size/taper relationship necessary to avoid unnecessary overflared canals and, at the same time, to allow the turbulence and solution exchange indispensable for the minimal cleaning and disinfection conditions to assure healing. The big picture is to address and discuss the close-to-optimum operative conditions to maximize ...
Revista Concinnitas, 2020
onde pesquisa "a poética da desaparição" e investiga os desdobramentos entre a experiência estéti... more onde pesquisa "a poética da desaparição" e investiga os desdobramentos entre a experiência estética/política e o aparecimento sensível da ideia, através da fotografia, do objeto e da pintura, sob orientação do prof. Dr. Alexandre Sá. Mestre pelo mesmo programa, participou de diversos editais e exposições como
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Papers by Daniele Moreira Cavalcante