Publications by authors named "Paulo J Palma"

15 Publications

  • Page 1 of 1

Influence of Preoperative Pulp Inflammation in the Outcome of Full Pulpotomy Using a Dog Model.

J Endod 2021 Sep 3;47(9):1417-1426. Epub 2021 Jul 3.

Institute of Endodontics, Faculty of Medicine, University of Coimbra, Coimbra, Portugal; Center for Innovation and Research in Oral Sciences, Faculty of Medicine, University of Coimbra, Coimbra, Portugal.

Introduction: This study aimed to evaluate the impact of preoperative pulp inflammation on the histologic outcome of full pulpotomy performed in mature permanent posterior teeth using 4 different biomaterials.

Methods: Five beagle dogs (providing a total of 120 roots) were selected. Dentin exposure was performed in teeth from the second and third quadrants. One week later, full pulpotomy procedures were performed using 4 different bioactive materials (ProRoot MTA [MTA], TotalFill BC Putty [BC], Biodentine [BIO], and an experimental cement [ie, pulp capping material]). The hemostasis time was registered. After 14 weeks, the animals were killed. Pulp-dentin tissues were histologically and radiographically assessed. The significance level was set at .05.

Results: Teeth with previously exposed dentin revealed a statistically significant increase in the time required to achieve hemostasis (P < .001), therefore confirming the pulp inflammation status induced by 1-week exposure of occlusal dentin before performing full pulpotomy. There was no radiographic evidence of root resorption, periapical radiolucency, or lamina dura alterations. No statistically significant differences were observed between normal and inflamed pulp regardless of the evaluated histologic parameters. Moreover, histologic data concerning calcified barrier formation and the pulp tissue response show better results for BIO without statistical differences compared with MTA or BC (P > .05). The pulp capping material presented a lower performance, with statistically significant differences being detected in regard to the remaining 3 tested materials (P < .001).

Conclusions: Radiographic and histologic outcomes of full pulpotomy are not jeopardized by short-term preoperative pulp inflammation. Moreover, BIO, MTA, and BC cements present suitable alternatives to be used as pulp capping agents.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.joen.2021.06.018DOI Listing
September 2021

Collagenated Porcine Heterologous Bone Grafts: Histomorphometric Evaluation of Bone Formation Using Different Physical Forms in a Rabbit Cancellous Bone Model.

Molecules 2021 Mar 2;26(5). Epub 2021 Mar 2.

Institute of Oral Implantology and Prosthodontics, Faculty of Medicine, University of Coimbra, 3000-075 Coimbra, Portugal.

Collagenated porcine-derived bone graft materials exhibit osteoconductive properties and the development of different formulations intends to enhance bone regeneration. This study aims to evaluate bone healing in a rabbit cancellous bone defect in response to grafting with different physicochemical forms of heterologous porcine bone. Twenty-six adult male New Zealand White rabbits received two critical size femoral bone defects per animal (n = 52), each randomly assigned to one of the five tested materials (Apatos, Gen-Os, mp3, Putty, and Gel 40). Animals were sacrificed at 15- and 30-days post-surgery. Qualitative and quantitative (new bone, particle and connective tissue percentages) histological analyses were performed. Histomorphometry showed statistically significant differences in all evaluated parameters between mp3 and both Putty and Gel 40 groups, regardless of the timepoint ( < 0.05). Moreover, statistical differences were observed between Apatos and both Putty ( = 0.014) and Gel 40 ( = 0.007) groups, at 30 days, in regard to particle percentage. Within each group, regarding new bone formation, mp3 showed significant differences ( = 0.028) between 15 (40.93 ± 3.49%) and 30 (52.49 ± 11.04%) days. Additionally, intragroup analysis concerning the percentage of particles revealed a significant reduction in particle occupied area from 15 to 30 days in mp3 and Gen-Os groups ( = 0.009). All mp3, Gen-Os and Apatos exhibited promising results in terms of new bone formation, thus presenting suitable alternatives to be used in bone regeneration.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/molecules26051339DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7958959PMC
March 2021

Regeneration of pulp-dentin complex using human stem cells of the apical papilla: in vivo interaction with two bioactive materials.

Clin Oral Investig 2021 Sep 25;25(9):5317-5329. Epub 2021 Feb 25.

Institute of Endodontics, Faculty of Medicine, University of Coimbra, Coimbra, Portugal.

Objectives: To compare the regenerative properties of human stem cells of the apical papilla (SCAPs) embedded in a platelet-rich plasma (PRP) scaffold, when implanted in vivo using an organotypic model composed of human root segments, with or without the presence of the bioactive cements - ProRoot MTA or Biodentine.

Material And Methods: SCAPs were isolated from third molars with incomplete rhizogenesis and expanded and characterized in vitro using stem cell and surface markers. The pluripotency of these cells was also assessed using adipogenic, chondrogenic, and osteogenic differentiation protocols. SCAPs together with a scaffold of PRP were added to the root segment lumen and the organotypic model implanted on the dorsal region of immunodeficient rats for a period of 4 months.

Results: Presence of SCAPs induced de novo formation of dentin-like and pulp-like tissue. A barrier of either ProRoot MTA or Biodentine did not significantly affect the fraction of sections from roots segments observed to contain deposition of hard material (P > 0.05). However, the area of newly deposited dentin was significantly greater in segments containing a barrier of Biodentine compared with ProRoot MTA (P < 0.001).

Conclusions And Clinical Relevance: SCAPs offer a viable alternative to other dental stem cells (DSCs) in their regenerative properties when enclosed in the microenvironment of human tooth roots. The present study also suggests that the presence of bioactive materials does not hinder or impede the formation of new hard tissues, but the presence of Biodentine may promote greater mineralized tissue deposition.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00784-021-03840-9DOI Listing
September 2021

Subcutaneous Implantation Assessment of New Calcium-Silicate Based Sealer for Warm Obturation.

Biomedicines 2021 Jan 1;9(1). Epub 2021 Jan 1.

Coimbra Institute for Clinical and Biomedical Research (iCBR) and Institute of Biophysics, Faculty of Medicine, University of Coimbra, 3000-548 Coimbra, Portugal.

Calcium silicate-based sealers were recently introduced as a new class of endodontic sealers, with potential further benefits due to their bioactivity. The aim of this study was to evaluate the biocompatibility of two new hydraulic calcium silicate-based sealers, TotalFill BC Sealer (FKG, La Chaux-des-Fonds, Switzerland) and TotalFill BC Sealer HiFlow (FKG, La Chaux-des-Fonds, Switzerland) through subcutaneous implantation in connective tissue of rats. Subcutaneous implantation was performed in 16 young Wistar rats. Four polyethylene tubes were implanted in each animal, one empty to serve as a control, and three filled with tested sealers: AH Plus as reference (Dentsply DeTrey, Konstanz, Germany), TotalFill BC Sealer (BC) and TotalFill BC Sealer HiFlow (HiFlow). Eight rats were euthanized at 8 days and the remaining eight at 30 days. Hematoxylin-eosin staining was used to score the inflammatory reaction, macrophage infiltrate and to measure the thickness of the fibrous capsule. von Kossa staining was performed to evaluate the mineralization level. Kruskal-Wallis test followed by Dunn's test was used to analyze non-parametric data. To analyze the influence of the implantation time within each material, a Mann-Whitney U test was performed. At eight days post-implantation, AH Plus induced a more intense inflammatory reaction when compared both with the control ( ≤ 0.001) and BC ( ≤ 0.01). HiFlow presented a higher score of macrophage infiltrate than control ( ≤ 0.01) and BC ( ≤ 0.05). The fibrous capsule thickness in this period was significantly higher for the BC group when compared to control ( ≤ 0.01) and AH Plus ( ≤ 0.05). The mineralization potential was higher for the HiFlow group when compared with the control ( ≤ 0.001) and AH Plus ( ≤ 0.001). At 30 days post-implantation, the score for the inflammatory reaction remained higher for the AH Plus group when compared both to control ( ≤ 0.01) and BC ( ≤ 0.001). The macrophage infiltrate of the HiFlow was significantly higher than control ( ≤ 0.001) and AH Plus groups ( ≤ 0.01), additionally, the fibrous capsule of the BC ( ≤ 0.001) and HiFlow ( ≤ 0.01) groups were both thicker than control. Mineralization potential was observed only on BC ( ≤ 0.05) and HiFlow groups ( ≤ 0.001), when compared to control). BC exhibited the best biocompatibility performance of all tested sealers and HiFlow provided the greatest induction of mineralized tissues. Both TotalFill BC Sealer and TotalFill BC Sealer HiFlow are biocompatible and show potential bioactivity when implanted in the subcutaneous tissue. Bioactivity was not found in AH Plus.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/biomedicines9010024DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7824331PMC
January 2021

Effect of restorative timing on shear bond strength of composite resin/calcium silicate-based cements adhesive interfaces.

Clin Oral Investig 2021 May 12;25(5):3131-3139. Epub 2020 Oct 12.

Center for Innovation and Research in Oral Sciences (CIROS), Faculty of Medicine, University of Coimbra, Coimbra, Portugal.

Objectives: The aim of this study was to evaluate the shear bond strength inherent to immediate and delayed definitive composite resin restorations, over three different biomaterials.

Methods: Fifty-four aluminum blocks were randomly assigned to six experimental groups (n = 9) according to the biomaterial (Biodentine, TotalFill BC Putty, or PCM) and restoration timing (immediate or 7 days delayed). Regarding the restorative procedures, a two-step self-etch bonding system (Clearfil SE Bond) was applied and subsequently restored using a flowable composite resin (SDR). After shear bond strength testing, fracture pattern analysis was performed. The significance level was set at α = 0.05.

Results: Within the immediate groups, Biodentine showed the highest mean shear bond strength value, with no statistically significant differences (P > 0.05) being detected when compared with both TotalFill (P = 0.072) and PCM (P = 0.232) groups. Regarding the delayed restoration groups, Biodentine and TotalFill presented the highest mean shear bond strength value, with statistical differences when compared with PCM (P = 0.002 and P = 0.043, respectively). No statistically significant differences (P > 0.05) were verified between both immediate and delayed groups for each tested biomaterial. Also, a statistically significant association was found between the fracture type and the biomaterial (P < 0.001).

Conclusions And Clinical Relevance: Our findings suggest that all tested biomaterials present suitable alternatives which allow to perform restorative procedures immediately after pulp capping biomaterial placement (3 or 12 min, depending on the bioactive cement), therefore requiring one single appointment to complete the procedure. Biodentine and TotalFill BC Putty have shown superior shear bond strength results when compared with PCM, within a delayed timeframe (7 days).
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00784-020-03640-7DOI Listing
May 2021

Evaluation of Root-End Preparation with Two Different Endodontic Microsurgery Ultrasonic Tips.

Biomedicines 2020 Sep 28;8(10). Epub 2020 Sep 28.

Institute of Endodontics, Faculty of Medicine, University of Coimbra, 3000-075 Coimbra, Portugal.

The aim of this study is to compare root-end preparation performed with two different ultrasonic tips-CVDentus and NSK-and respective time requirements. After root-end resection, 32 teeth were randomly divided in two groups, according to the ultrasonic tip used for root-end preparation. Preparation time was recorded. Photomicrographs were taken to assess the following parameters: root surface microcracking, marginal integrity and presence of debris. One ultrasonic tip from each group was analyzed through scanning electron microscopy before and after root-end preparation. The significance level was set at α = 0.05. Incidence of microcracks in both groups was 12.5%. Solely intracanal microcracking was found, consistently positioned within the widest side of the remaining dentine. No statistically significant differences were verified between both experimental groups regarding marginal integrity ( = 0.102) and preparation time ( = 0.780), whereas statistical differences ( = 0.003) were found concerning the presence of debris (the minimum registered score was mostly verified in CVDentus group). NSK tips showed major morphological changes, with extensive surface wear and noticeable loss of particles, which was not verified on CVDentus tips. Our findings suggest significant differences regarding root-end preparation walls quality, with CVDentus tips showing better results. Concerning microcracking, as well as preparation time and marginal integrity, both ultrasonic tips showed similar results. Qualitative analysis exposed NSK tips major morphological changes and wear after use, which was not verified on CVDentus tips.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/biomedicines8100383DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7601836PMC
September 2020

Long-Term Prognosis of Endodontic Microsurgery-A Systematic Review and Meta-Analysis.

Medicina (Kaunas) 2020 Sep 3;56(9). Epub 2020 Sep 3.

Institute of Endodontics, Faculty of Medicine, University of Coimbra, 3000-132 Coimbra, Portugal.

The long-term outcome of endodontic microsurgery (EMS) performed on root-filled teeth affected by post-treatment apical periodontitis (AP) has been a matter of debate, re-launched by the introduction of novel root-end filling materials which have been proven to improve the short-term outcome of EMS. The purpose of this systematic review and meta-analysis is to evaluate the clinical and radiographic long-term outcome of endodontic microsurgery in teeth diagnosed with secondary AP through radiographic evaluation. This systematic review and meta-analysis followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Inclusion and exclusion criteria were defined a priori to select the best longitudinal evidence. Only randomized clinical trials (RCT) and prospective clinical studies (PCS), with a follow-up ≥ 2-year, and exhibiting well-established clinical and radiographic outcome criteria, were selected. A total of 573 articles were obtained, from which 10 fulfill inclusion criteria: 6 PCS and 4 RCT. Meta-analysis showed a pooled proportion of success rate of 91.3%, from an overall amount of 453 treated teeth included in RCT; from overall 839 included teeth in PCS, a pooled success rate of 78.4% was observed, with the follow-up time ranging from 2 to 13-years. Survival rate outcomes varied from 79 to 100% for the same follow-up period. Five prognostic factors with influence on the outcome were disclosed: smoking habits, tooth location and type, absence/presence of dentinal defects, interproximal bone level, and root-end filling material. High success rates and predictable results can be expected when EMS is performed by trained endodontists, allowing good prognosis and preservation of teeth affected by secondary AP.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/medicina56090447DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7558840PMC
September 2020

An Insight into Advanced Approaches for Photosensitizer Optimization in Endodontics-A Critical Review.

J Funct Biomater 2019 Sep 30;10(4). Epub 2019 Sep 30.

Institute of Endodontics, Faculty of Medicine, University of Coimbra, 3000-075 Coimbra, Portugal.

Apical periodontitis is a biofilm-mediated disease; therefore, an antimicrobial approach is essential to cure or prevent its development. In the quest for efficient strategies to achieve this objective, antimicrobial photodynamic therapy (aPDT) has emerged as an alternative to classical endodontic irrigation solutions and antibiotics. The aim of the present critical review is to summarize the available evidence on photosensitizers (PSs) which has been confirmed in numerous studies from diverse areas combined with several antimicrobial strategies, as well as emerging options in order to optimize their properties and effects that might be translational and useful in the near future in basic endodontic research. Published data notably support the need for continuing the search for an ideal endodontic photosensitizer, that is, one which acts as an excellent antimicrobial agent without causing toxicity to the human host cells or presenting the risk of tooth discoloration. The current literature on experimental studies mainly relies on assessment of mixed disinfection protocols, combining approaches which are already available with aPDT as an adjunct therapy. In this review, several approaches concerning aPDT efficiency are appraised, such as the use of bacteriophages, biopolymers, drug and light delivery systems, efflux pump inhibitors, negative pressure systems, and peptides. The authors also analyzed their combination with other approaches for aPDT improvement, such as sonodynamic therapy. All of the aforementioned techniques have already been tested, and we highlight the biological challenges of each formulation, predicting that the collected information may encourage the development of other effective photoactive materials, in addition to being useful in endodontic basic research. Moreover, special attention is dedicated to studies on detailed conditions, aPDT features with a focus on PS enhancer strategies, and the respective final antimicrobial outcomes. From all the mentioned approaches, the two which are most widely discussed and which show the most promising outcomes for endodontic purposes are drug delivery systems (with strong development in nanoparticles) and PS solubilizers.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/jfb10040044DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6963755PMC
September 2019

Biocompatibility of a bioceramic silicone-based sealer in subcutaneous tissue.

J Oral Sci 2019 ;61(1):171-177

Institute of Biophysics, Faculty of Medicine, University of Coimbra.

This study evaluated the biocompatibility of a new silicone-based sealer (GuttaFlow Bioseal) in rat subcutaneous tissue and compared the results with those for GuttaFlow2 and AH Plus. Each of 16 Wistar rats received four subcutaneous tissue implants, namely, GuttaFlow Bioseal, GuttaFlow2, AH Plus, and one empty polyethylene tube. Eight rats were euthanized at day 8 and the remaining eight at day 30. Histological sections were stained with haematoxylin and eosin and analysed with a light microscope. Scores were established for inflammatory reaction, macrophage infiltrate, thickness of the fibrous capsule, and vascular changes. Differences between groups were assessed by using the Friedman test with Bonferroni correction. Histological analysis showed that GuttaFlow Bioseal had the lowest inflammatory reaction of all tested sealers at day 8. At day 30, the silicone-based sealers had similar inflammation profiles, but inflammation scores were nonsignificantly higher for AH Plus than for the negative control. The inflammatory reaction decreased from day 8 to day 30 in all sealers. GuttaFlow Bioseal had the most macrophage infiltrate. Under the present experimental conditions, GuttaFlow Bioseal induced limited inflammatory reactions at days 8 and 30, and initial inflammatory reactions to GuttaFlow2 and AH Plus subsided within 30 days. All tested sealers exhibited satisfactory biocompatibility at day 30 after subcutaneous implantation.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.2334/josnusd.18-0145DOI Listing
August 2019

Six-Month Color Stability Assessment of Two Calcium Silicate-Based Cements Used in Regenerative Endodontic Procedures.

J Funct Biomater 2019 Feb 28;10(1). Epub 2019 Feb 28.

Institute of Operative Dentistry, Faculty of Medicine, University of Coimbra, 3000-075 Coimbra, Portugal.

Aim: The purpose of the present study is to assess the color stability of two calcium silicate-based cements (CSCs) used in regenerative endodontic procedures (REPs).

Methods: A total of 40 acrylic single-rooted transparent teeth, with immature apex, were used. Root canals were filled up to 3 mm below the level of the cementoenamel junction, with either saline solution (Mineral Trioxide Aggregate (MTA)/saline and Biodentine/saline) or blood (MTA/blood and Biodentine/blood). Subsequently, ProRoot MTA or Biodentine was placed in the root canal to create a cervical barrier. Color measurement was carried out at four different evaluation periods (3 h, 72 h, 7 days, and 6 months). Shade analysis within the L* a* b* color space was performed and color variation (∆E) calculated. The significance level for statistical analysis was set at < 0.05.

Results: The four groups showed a significant decrease in L* values over time. The ΔE value increased over time for all groups but was not statistically significant for the Biodentine/blood group. Two-way ANOVA showed no interaction between the CSC and treatment (contact with saline solution or blood). CSC used was the factor responsible for ΔE over time, inducing statistically significant color variations from T to T ( = 0.04) and T to T ( < 0.01). After 6 months, MTA/saline had 5.08 ( = 0.001) higher ΔE than Biodentine/Saline and the MTA/blood had 3.65 ( = 0.009) higher than Biodentine/blood.

Conclusions: After 6 months, regardless of blood exposure, Biodentine exhibits superior color stability compared to MTA. Biodentine might be a suitable alternative to MTA as a cervical barrier material in REPs.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/jfb10010014DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6462979PMC
February 2019

Effects of a New Bioceramic Material on Human Apical Papilla Cells.

J Funct Biomater 2018 Dec 16;9(4). Epub 2018 Dec 16.

Institute of Endodontics, Faculty of Medicine, University of Coimbra, Coimbra 3000-075 Portugal.

Background: The development of materials with bioregenerative properties is critically important for vital pulp therapies and regenerative endodontic procedures. The aim of this study was to evaluate the cytocompatibility and cytotoxicity of a new endodontic biomaterial, PulpGuard, in comparison with two other biomaterials widely used in endodontic procedures, ProRoot Mineral Trioxide Aggregate (MTA) and Biodentine.

Methods: Apical papilla cells (APCs) were isolated from third molars with incomplete rhizogenesis from patients with orthodontic indication for dental extraction. Cultured APCs were incubated for 24, 48, or 72 h with different dilutions of eluates prepared from the three materials. Cellular viability, mobility, and proliferation were assessed in vitro using the Alamar Blue assay and a wound-healing test. The cells were also cultured in direct contact with the surface of each material. These were then analyzed via Scanning Electron Microscopy (SEM), and the surface chemical composition was determined by Energy-Dispersive Spectroscopy (EDS).

Results: Cells incubated in the presence of eluates extracted from ProRoot MTA and PulpGuard presented rates of viability comparable to those of control cells; in contrast, undiluted Biodentine eluates induced a significant reduction of cellular viability. The wound-healing assay revealed that eluates from ProRoot MTA and PulpGuard allowed for unhindered cellular migration and proliferation. Cellular adhesion was observed on the surface of all materials tested. Consistent with their disclosed composition, EDS analysis found high relative abundance of calcium in Biodentine and ProRoot MTA and high abundance of silicon in PulpGuard. Significant amounts of zinc and calcium were also present in PulpGuard discs. Concerning solubility, Biodentine and ProRoot MTA presented mild weight loss after eluate extraction, while PulpGuard discs showed significant water uptake.

Conclusions: PulpGuard displayed a good in vitro cytocompatibility profile and did not significantly affect the proliferation and migration rates of APCs. Cells cultured in the presence of PulpGuard eluates displayed a similar profile to those cultured with eluates from the widely used endodontic cement ProRoot MTA.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/jfb9040074DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6306901PMC
December 2018

Does Delayed Restoration Improve Shear Bond Strength of Different Restorative Protocols to Calcium Silicate-Based Cements?

Materials (Basel) 2018 Nov 8;11(11). Epub 2018 Nov 8.

Department of Dentistry, Faculty of Medicine, University of Coimbra, 3000-075 Coimbra, Portugal.

The purpose of the present study was to assess the proper time to perform a restoration (immediately or delayed) after placement of two calcium silicate-based cements (CSCs) and to test the performance of two different restorative protocols regarding shear bond strength (SBS). Seventy-five acrylic blocks were randomly divided into five groups ( = 15). Specimens were filled with either ProRoot MTA (Dentsply Tulsa Dental) or Biodentine (Septodont). The restoration was performed at an immediate (12 min) or delayed (seven days) timeframe, using a resin-based flowable composite (SDR) (bonded to the CSC using a universal bonding system) or glass ionomer cement (GIC) as restorative materials. SBS was measured using a universal testing machine. Fractured surfaces were evaluated, and the pattern was registered. Statistical analysis was performed using the Dunn⁻Sidak post hoc test ( < 0.05). Biodentine/immediate SDR showed the highest mean SBS value (4.44 MPa), with statistically significant differences when compared to mineral trioxide aggregate (MTA)/GIC (1.14 MPa) and MTA/immediate SDR (1.33 MPa). MTA/GIC and MTA/immediate SDR did not present significant differences regarding SBS. No statistical differences were verified concerning mean SBS between both CSCs within the 7 day groups. MTA/delayed SDR (3.86 MPa) presented statistical differences compared to MTA/immediate SDR, whereas no differences were observed regarding Biodentine performance (Biodentine/immediate SDR and Biodentine/delayed SDR (3.09 MPa)). Bonding procedures directly on top of MTA might be preferably performed at a delayed timeframe, whereas Biodentine might allow for immediate restoration.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/ma11112216DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6265959PMC
November 2018

Histologic Evaluation of Regenerative Endodontic Procedures with the Use of Chitosan Scaffolds in Immature Dog Teeth with Apical Periodontitis.

J Endod 2017 Aug 31;43(8):1279-1287. Epub 2017 May 31.

Department of Dentistry, Faculty of Medicine, University of Coimbra, Coimbra, Portugal.

Introduction: The aim of this study was to evaluate histologically the newly formed tissues after regenerative endodontic procedures (REPs) in dogs using either a blood clot (BC) or 2 different formulations of a chitosan hydrogel as scaffolds.

Methods: Apical periodontitis was induced by inoculating immature teeth with oral plaque in 4 beagle dogs. Teeth (n = 96) were divided into 2 control (n = 20) and 4 test groups (n = 76) according to the treatment: apexification and REPs with BC, sodium hyaluronate:chitosan (HA:CS) scaffolds, or pectin:chitosan (P:CS) scaffolds. All root canals were disinfected with 2.5% sodium hypochlorite and a triple antibiotic paste intracanal medicament before evoked bleeding, clot formation, or scaffold placement. Thirteen weeks after treatment, the animals were sacrificed and the jaw blocks harvested for histologic processing, histomorphometric analysis, and statistical analysis.

Results: The lumens of the root canals were completely filled with mineral trioxide aggregate with evidence of a mineralized apical bridge between the root canal walls in 83% of the samples in the apexification group. Vital vascularized tissue was found in the REP groups; apical closure happened in 66.7% of these treatments, and root growth was detected more often as an increase in thickness (85.6%) than in length (45.6%). The greatest amount of mineralized tissue inside the canal was observed in the BC group, with statistical significance compared with the HA:CS and P:CS groups (P < .05). Further histologic evaluation revealed the presence of apical papilla.

Conclusions: The addition of chitosan scaffolds to blood in regenerative procedures in dogs did not improve the formation of new mineralized tissues along the root canal walls or the histologic evidence of the regeneration of a pulp-dentin complex.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.joen.2017.03.005DOI Listing
August 2017

1-year In Vitro Evaluation of Tooth Discoloration Induced by 2 Calcium Silicate-based Cements.

J Endod 2016 Sep 3;42(9):1403-7. Epub 2016 Aug 3.

Dentistry Department, Faculty of Medicine, University of Coimbra, Coimbra, Portugal.

Introduction: The purpose of this study was to compare tooth discoloration that occurs in teeth filled with ProRoot MTA (DENTSPLY Tulsa Dental Specialties, Tulsa, OK) or Biodentine (Septodont, Saint Maur des Fossés, France) over the course of 1 year.

Methods: Twenty-eight intact premolars were resected 2 mm apical to the cementoenamel junction and the pulp tissues extirpated via the cervical cut. After the preparation of occlusal access to the pulp chamber, specimens were assigned into 4 groups according to a stratified randomization sampling process: group 1, negative control (dry sterile cotton pellet); group 2, positive control (blood-moistened cotton pellet); group 3, ProRoot WMTA (DENTSPLY Tulsa Dental Specialties); and group 4, Biodentine. The experimental materials were condensed into the crowns and the access sealed with glass ionomer restorative cement. Color was assessed at baseline (before placement of the materials), immediately after material filling, after 6 weeks of storage, and after 1 year using the Commission International de I'Eclairage L*a*b* system. Change in color, ΔE, was compared among groups and over time using analysis of variance.

Results: The 4 groups showed a significant decrease in L* values over time. Differences between Biodentine and WMTA were detected after 1 year, with the greater variation associated with WMTA (P = .001). The 4 groups presented a significant increase in ΔE from baseline to 1 year. All groups revealed perceptible color changes (ΔE > 2.3) between immediately after material filling and after 6 weeks and after 6 weeks and 1 year. After 1 year, no differences could be detected between Biodentine and WMTA.

Conclusions: Delayed tooth discoloration was detected for the 2 materials at the 1-year evaluation, but it was more evident for ProRoot MTA than Biodentine. Luminance was the most affected parameter, with a higher decrease for ProRoot MTA.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.joen.2016.06.012DOI Listing
September 2016

Periapical inflammation subsequent to coronal inoculation of dog teeth root filled with resilon/epiphany in 1 or 2 treatment sessions with chlorhexidine medication.

J Endod 2014 Jun 15;40(6):837-41. Epub 2013 Dec 15.

Discipline of Endodontics, Faculty of Dentistry, University of Toronto, Toronto, Ontario, Canada.

Introduction: Therapeutic methods that inhibit microbial ingress into filled root canals are desirable. This in vivo study assessed the inhibition of periapical inflammation subsequent to coronal inoculation in canals medicated with 2% chlorhexidine gel and filled with Resilon/Epiphany (Pentron Clinical Technologies, Wallingford, CT).

Methods: Six Beagle dogs each had 10 two-rooted premolars treated. In group 1 (n = 36 roots), 1 root/tooth had the canal conditioned with Primer Epiphany, filled with Epiphany sealer and Resilon core in 1 session, and coronally sealed with PhotacFil. In group 2 (n = 36 roots), the second root/tooth had the canal medicated with 2% chlorhexidine gel for 1 week and then filled and coronally sealed as in group 1. After 3 weeks, canals were exposed to the oral environment for 7 days, inoculated with isologous plaque, and coronally sealed. Negative controls treated as groups 1 and 2 remained sealed. Positive controls had canals unfilled and exposed. Seven months after inoculation, dogs were euthanized; jaw blocks processed for histologic examination; and periapical inflammation (PI) recorded as none, mild, or severe.

Results: In groups 1 and 2, severe PI occurred in 5 of 65 roots (8%) and mild PI in 18 of 65 roots (28%) with a significantly higher (P = .031) PI incidence in group 2 than in group 1. Negative controls had only mild PI in 9 of 29 roots (31%). Roots medicated with 2% chlorhexidine gel had mild PI significantly more (P = .009) than roots filled in 1 session (more than 2-fold).

Conclusions: Intracanal medication with 2% chlorhexidine gel and root filling with Resilon/Epiphany did not effectively inhibit apical periodontitis subsequent to coronal inoculation.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.joen.2013.10.023DOI Listing
June 2014
-->