Traditionally, human bone marrow-derived and mesenchymal stem cells from the dental apical papill... more Traditionally, human bone marrow-derived and mesenchymal stem cells from the dental apical papilla (BM-MSC and SCAP, respectively) are cultivated in normal atmospheric level of oxygen (21%). Their isolation and transfer to culture represents a shift from 2-8% in their niche to 21% in culture. Their re-implantation would mean a shift from 21% to 2-8% in the implantation site
The Journal of the American Dental Association, 2021
BACKGROUND Post space preparation can increase the risk of experiencing perforation and root frac... more BACKGROUND Post space preparation can increase the risk of experiencing perforation and root fracture. The authors assessed remaining dentin thickness after post space preparation and the fit of different prefabricated posts to root canal preparation systems in a theoretical model. METHODS Ten datasets per type of tooth from cone-beam computed tomography were analyzed to determine the minimum root diameter from 5 through 13 mm from the apical foramen. The preparation shapes of 10 root canal preparation systems were calculated and compared with the root dimensions to determine the remaining dentin thickness. Eight post brands were compared with root dimensions to determine the areas where there was less than 1 mm dentin thickness. RESULTS The average root canal preparation shape produced canal diameters of 0.57 mm at 5 mm from the canal terminus and 0.94 mm at 13 mm from the canal terminus. The mean post size tip diameter was 1.03 mm, which is larger than the dimensions of the average canal preparation. Post preparation would result in less than 1 mm of dentin thickness remaining in premolars, smaller roots of molars, and mandibular incisors. The area with less than 1 mm of dentin thickness was around the post tip. CONCLUSIONS Endosequence Fiber Post (Brasseler USA), RelyX Fiber Post 3D (3M), and Rebilda (VOCO) were the better fitting posts with the root canal preparation shapes. PRACTICAL IMPLICATIONS Many posts would result in less than 1 mm dentin thickness. Clinicians should use posts that fit their root canal preparations to minimize dentin removal.
INTRODUCTION The aim of the present study was to assess the effects of different silicate-based s... more INTRODUCTION The aim of the present study was to assess the effects of different silicate-based sealers (ie, BioRoot RCS [Septodont, Saint Maur des Fosses, France], ProRoot ES [Dentsply Sirona, York, PA], and MTA Fillapex [Angelus, Londrina, PR, Brazil]) on cytokine production and viability of human periodontal ligament stem cells (PDLSCs). AH Plus (Dentsply DeTrey GmbH, Konstanz, Germany) was used as a reference material. METHODS PDLSCs were cultured either in 2-dimensional or 3-dimensional conditions (in 0.15%-0.5% PuraMatrix [BD Biosciences, Bedford, MA]) for 24 hours with eluates from set endodontic sealers. Additionally, the toxicity of eluates from endodontic sealers was evaluated using an in vitro root model experimental procedure. PDLSC viability was determined using the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide assay. PDLSC culture medium was used for cytokine quantification (interleukin [IL]-6, IL-8, growth-regulated oncogene, IL,-4 and IL-10) using the HCYTMAG-60K-PX41 Milliplex kit (EMD Millipore, Burlington, MA). RESULTS In 2-dimensional culture conditions, BioRoot RCS revealed a good PDLSC viability rate. ProRoot ES had no effect on PDLSC viability regardless of the dilution. MTA Fillapex was strongly cytotoxic even at the lowest extract dilutions (1:1, 1:2, and 1:4). Encapsulation of PDLSCs in PuraMatrix tended to decrease the cytotoxic effect of the sealers. In the 3-dimensional in vitro root model experimental procedure, BioRoot RCS, ProRoot ES, and MTA Fillapex revealed a cytocompatibility pattern. Different calcium silicate-based sealers exhibited different proinflammatory cytokine production. BioRoot RCS greatly stimulated the release of IL-10 and, to a lesser degree, IL-4 by PDLSCs (P < .05). CONCLUSIONS BioRoot RCS and ProRoot ES did not induce proinflammatory cytokines and promoted anti-inflammatory cytokine secretion by PDLSCs that may have a positive local impact by attenuating an initial inflammatory response.
A comparison of the preparation ability of two root canal instrumentation systems in oval‐shaped ... more A comparison of the preparation ability of two root canal instrumentation systems in oval‐shaped canals using micro‐computed tomography was undertaken. Thirty extracted, single‐rooted, human mandibular premolars with radiographically similar canal morphology were selected, allocated to two groups (N = 15) and prepared with TRUShape or Vortex Blue (VB). Each sample was subjected to three scans (20 μm resolution): pre‐preparation and after preparation to sizes #30 and #40. Three‐dimensional data sets were evaluated for canal volume, surface area and surface treatment. Matched axial slices in apical, middle and coronal root thirds were evaluated for cross‐sectional area, roundness and transportation. Preparation with both instruments increased canal volumes and surface areas similarly and significantly (P < 0.001) with no significant difference between groups. TRUShape significantly enhanced surface treatment at both apical sizes (P < 0.05). Transportation exceeded 100 μm in only...
This study aimed to compare fluid movements generated from photon-induced photoacoustic streaming... more This study aimed to compare fluid movements generated from photon-induced photoacoustic streaming (PIPS) and passive ultrasonic irrigation (PUI). Particle Image Velocimetry (PIV) was performed using 6-μm melamine spheres in water. Measurement areas were 3-mm-long sections of the canal in the coronal, midroot and apical regions for PIPS (erbium/yttrium-aluminium garnet (Er:YAG) laser set at 15 Hz with 20 mJ), or passive ultrasonic irrigation (PUI, non-cutting insert at 30 % unit power) was performed in simulated root canals prepared to an apical size #30/0.04 taper. Fluid movement was analysed directly subjacent to the apical ends of ultrasonic insert or fiber optic tips as well as at midroot and apically. During PUI, measured average velocities were around 0.03 m/s in the immediate vicinity of the sides and tip of the ultrasonic file. Speeds decayed to non-measureable values at a distance of about 2 mm from the sides and tip. During PIPS, typical average speeds were about ten times higher than those measured for PUI, and they were measured throughout the length of the canal, at distances up to 20 mm away. PIPS caused higher average fluid speeds when compared to PUI, both close and distant from the instrument. The findings of this study could be relevant to the debriding and disinfecting stage of endodontic therapy. Irrigation enhancement beyond needle irrigation is relevant to more effectively eradicate microorganisms from root canal systems. PIPS may be an alternative approach due to its ability to create high streaming velocities further away from the activation source compared to ultrasonic activation.
ABSTRACTAimsThis systematic review aimed to compare the efficiency of orifice barriers in prevent... more ABSTRACTAimsThis systematic review aimed to compare the efficiency of orifice barriers in preventing coronal microleakage in vitro.MethodsArticles published in English, German and Chinese were searched for studies describing microleakage assays for the bacterial penetration of root canal‐treated teeth in vitro. The final sample included 18 articles for review and meta‐analysis. Risk ratios and confidence intervals were determined for dichotomous variables. Ten publications using bacterial leakage models contributed to the meta‐analysis.ResultsThe addition of orifice barriers to a root canal filling was overall effective, shown by risk ratios (RR) and 95% confidence intervals (CI) demonstrating reduced microleakage with glass ionomer cement (GIC) (RR 0.37, 95% CI 0.26–0.53, P < 0.001), resin‐modified GIC (RR 0.32, 95% CI 0.15–0.67, P = 0.01), composite resin (RR 0.54, 95% CI 0.38–0.75, P < 0.001), mineral trioxide aggregate (MTA) (RR 0.25, 95% CI 0.12–0.52, P < 0.001) and Ca...
This narrative review will focus on the evolution, present and future of engine‐driven root canal... more This narrative review will focus on the evolution, present and future of engine‐driven root canal preparation. Root canal preparation changed drastically when Walia in 1988 introduced the use of nickel‐titanium (NiTi) alloys in Endodontics. In 2013, five generations of NiTi endodontic instruments had been established based on their metallurgical, mechanical properties and design features. Since then, manufacturers have been introducing further major changes in instrument design and characteristics that have not been translated in new recognized generations of instruments. In general, those changes have demonstrated enhanced instrument properties, but it is not clear yet if all those improvements are directly translated to an improvement in clinical success. This narrative review attempts to address the present status of engine‐driven instruments in terms of both evidence from laboratory‐based studies and clinical data, to identify potential further generations of instruments, and la...
Inflammation is a crucial step prior to healing, and the regulatory effects of endodontic materia... more Inflammation is a crucial step prior to healing, and the regulatory effects of endodontic materials on the immune response can influence tissue repair. This review aimed to answer whether endodontic sealers can modulate the immune cells and inflammation. An electronic search in Scopus, Web of Science, PubMed, and Google Scholar databases were performed. This systematic review was mainly based on PRISMA guidelines, and the risk of bias was evaluated by SYRCLEs and the Modified CONSORT checklist for in vivo and in vitro studies, respectively. In total, 28 articles: 22 in vitro studies, and six in vivo studies were included in this systematic review. AH Plus and AH 26 can down-regulate iNOS mRNA, while S-PRG sealers can down-regulate p65 of NF-κB pathways to inhibit the production of TNF-α, IL-1, and IL-6. In vitro and in vivo studies suggested that various endodontic sealers exhibited immunomodulatory impact in macrophages polarization and inflammatory cytokine production, which could...
An amendment to this paper has been published and can be accessed via a link at the top of the pa... more An amendment to this paper has been published and can be accessed via a link at the top of the paper.
Traditionally, human bone marrow-derived and mesenchymal stem cells from the dental apical papill... more Traditionally, human bone marrow-derived and mesenchymal stem cells from the dental apical papilla (BM-MSC and SCAP, respectively) are cultivated in normal atmospheric level of oxygen (21%). Their isolation and transfer to culture represents a shift from 2-8% in their niche to 21% in culture. Their re-implantation would mean a shift from 21% to 2-8% in the implantation site
The Journal of the American Dental Association, 2021
BACKGROUND Post space preparation can increase the risk of experiencing perforation and root frac... more BACKGROUND Post space preparation can increase the risk of experiencing perforation and root fracture. The authors assessed remaining dentin thickness after post space preparation and the fit of different prefabricated posts to root canal preparation systems in a theoretical model. METHODS Ten datasets per type of tooth from cone-beam computed tomography were analyzed to determine the minimum root diameter from 5 through 13 mm from the apical foramen. The preparation shapes of 10 root canal preparation systems were calculated and compared with the root dimensions to determine the remaining dentin thickness. Eight post brands were compared with root dimensions to determine the areas where there was less than 1 mm dentin thickness. RESULTS The average root canal preparation shape produced canal diameters of 0.57 mm at 5 mm from the canal terminus and 0.94 mm at 13 mm from the canal terminus. The mean post size tip diameter was 1.03 mm, which is larger than the dimensions of the average canal preparation. Post preparation would result in less than 1 mm of dentin thickness remaining in premolars, smaller roots of molars, and mandibular incisors. The area with less than 1 mm of dentin thickness was around the post tip. CONCLUSIONS Endosequence Fiber Post (Brasseler USA), RelyX Fiber Post 3D (3M), and Rebilda (VOCO) were the better fitting posts with the root canal preparation shapes. PRACTICAL IMPLICATIONS Many posts would result in less than 1 mm dentin thickness. Clinicians should use posts that fit their root canal preparations to minimize dentin removal.
INTRODUCTION The aim of the present study was to assess the effects of different silicate-based s... more INTRODUCTION The aim of the present study was to assess the effects of different silicate-based sealers (ie, BioRoot RCS [Septodont, Saint Maur des Fosses, France], ProRoot ES [Dentsply Sirona, York, PA], and MTA Fillapex [Angelus, Londrina, PR, Brazil]) on cytokine production and viability of human periodontal ligament stem cells (PDLSCs). AH Plus (Dentsply DeTrey GmbH, Konstanz, Germany) was used as a reference material. METHODS PDLSCs were cultured either in 2-dimensional or 3-dimensional conditions (in 0.15%-0.5% PuraMatrix [BD Biosciences, Bedford, MA]) for 24 hours with eluates from set endodontic sealers. Additionally, the toxicity of eluates from endodontic sealers was evaluated using an in vitro root model experimental procedure. PDLSC viability was determined using the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide assay. PDLSC culture medium was used for cytokine quantification (interleukin [IL]-6, IL-8, growth-regulated oncogene, IL,-4 and IL-10) using the HCYTMAG-60K-PX41 Milliplex kit (EMD Millipore, Burlington, MA). RESULTS In 2-dimensional culture conditions, BioRoot RCS revealed a good PDLSC viability rate. ProRoot ES had no effect on PDLSC viability regardless of the dilution. MTA Fillapex was strongly cytotoxic even at the lowest extract dilutions (1:1, 1:2, and 1:4). Encapsulation of PDLSCs in PuraMatrix tended to decrease the cytotoxic effect of the sealers. In the 3-dimensional in vitro root model experimental procedure, BioRoot RCS, ProRoot ES, and MTA Fillapex revealed a cytocompatibility pattern. Different calcium silicate-based sealers exhibited different proinflammatory cytokine production. BioRoot RCS greatly stimulated the release of IL-10 and, to a lesser degree, IL-4 by PDLSCs (P < .05). CONCLUSIONS BioRoot RCS and ProRoot ES did not induce proinflammatory cytokines and promoted anti-inflammatory cytokine secretion by PDLSCs that may have a positive local impact by attenuating an initial inflammatory response.
A comparison of the preparation ability of two root canal instrumentation systems in oval‐shaped ... more A comparison of the preparation ability of two root canal instrumentation systems in oval‐shaped canals using micro‐computed tomography was undertaken. Thirty extracted, single‐rooted, human mandibular premolars with radiographically similar canal morphology were selected, allocated to two groups (N = 15) and prepared with TRUShape or Vortex Blue (VB). Each sample was subjected to three scans (20 μm resolution): pre‐preparation and after preparation to sizes #30 and #40. Three‐dimensional data sets were evaluated for canal volume, surface area and surface treatment. Matched axial slices in apical, middle and coronal root thirds were evaluated for cross‐sectional area, roundness and transportation. Preparation with both instruments increased canal volumes and surface areas similarly and significantly (P < 0.001) with no significant difference between groups. TRUShape significantly enhanced surface treatment at both apical sizes (P < 0.05). Transportation exceeded 100 μm in only...
This study aimed to compare fluid movements generated from photon-induced photoacoustic streaming... more This study aimed to compare fluid movements generated from photon-induced photoacoustic streaming (PIPS) and passive ultrasonic irrigation (PUI). Particle Image Velocimetry (PIV) was performed using 6-μm melamine spheres in water. Measurement areas were 3-mm-long sections of the canal in the coronal, midroot and apical regions for PIPS (erbium/yttrium-aluminium garnet (Er:YAG) laser set at 15 Hz with 20 mJ), or passive ultrasonic irrigation (PUI, non-cutting insert at 30 % unit power) was performed in simulated root canals prepared to an apical size #30/0.04 taper. Fluid movement was analysed directly subjacent to the apical ends of ultrasonic insert or fiber optic tips as well as at midroot and apically. During PUI, measured average velocities were around 0.03 m/s in the immediate vicinity of the sides and tip of the ultrasonic file. Speeds decayed to non-measureable values at a distance of about 2 mm from the sides and tip. During PIPS, typical average speeds were about ten times higher than those measured for PUI, and they were measured throughout the length of the canal, at distances up to 20 mm away. PIPS caused higher average fluid speeds when compared to PUI, both close and distant from the instrument. The findings of this study could be relevant to the debriding and disinfecting stage of endodontic therapy. Irrigation enhancement beyond needle irrigation is relevant to more effectively eradicate microorganisms from root canal systems. PIPS may be an alternative approach due to its ability to create high streaming velocities further away from the activation source compared to ultrasonic activation.
ABSTRACTAimsThis systematic review aimed to compare the efficiency of orifice barriers in prevent... more ABSTRACTAimsThis systematic review aimed to compare the efficiency of orifice barriers in preventing coronal microleakage in vitro.MethodsArticles published in English, German and Chinese were searched for studies describing microleakage assays for the bacterial penetration of root canal‐treated teeth in vitro. The final sample included 18 articles for review and meta‐analysis. Risk ratios and confidence intervals were determined for dichotomous variables. Ten publications using bacterial leakage models contributed to the meta‐analysis.ResultsThe addition of orifice barriers to a root canal filling was overall effective, shown by risk ratios (RR) and 95% confidence intervals (CI) demonstrating reduced microleakage with glass ionomer cement (GIC) (RR 0.37, 95% CI 0.26–0.53, P < 0.001), resin‐modified GIC (RR 0.32, 95% CI 0.15–0.67, P = 0.01), composite resin (RR 0.54, 95% CI 0.38–0.75, P < 0.001), mineral trioxide aggregate (MTA) (RR 0.25, 95% CI 0.12–0.52, P < 0.001) and Ca...
This narrative review will focus on the evolution, present and future of engine‐driven root canal... more This narrative review will focus on the evolution, present and future of engine‐driven root canal preparation. Root canal preparation changed drastically when Walia in 1988 introduced the use of nickel‐titanium (NiTi) alloys in Endodontics. In 2013, five generations of NiTi endodontic instruments had been established based on their metallurgical, mechanical properties and design features. Since then, manufacturers have been introducing further major changes in instrument design and characteristics that have not been translated in new recognized generations of instruments. In general, those changes have demonstrated enhanced instrument properties, but it is not clear yet if all those improvements are directly translated to an improvement in clinical success. This narrative review attempts to address the present status of engine‐driven instruments in terms of both evidence from laboratory‐based studies and clinical data, to identify potential further generations of instruments, and la...
Inflammation is a crucial step prior to healing, and the regulatory effects of endodontic materia... more Inflammation is a crucial step prior to healing, and the regulatory effects of endodontic materials on the immune response can influence tissue repair. This review aimed to answer whether endodontic sealers can modulate the immune cells and inflammation. An electronic search in Scopus, Web of Science, PubMed, and Google Scholar databases were performed. This systematic review was mainly based on PRISMA guidelines, and the risk of bias was evaluated by SYRCLEs and the Modified CONSORT checklist for in vivo and in vitro studies, respectively. In total, 28 articles: 22 in vitro studies, and six in vivo studies were included in this systematic review. AH Plus and AH 26 can down-regulate iNOS mRNA, while S-PRG sealers can down-regulate p65 of NF-κB pathways to inhibit the production of TNF-α, IL-1, and IL-6. In vitro and in vivo studies suggested that various endodontic sealers exhibited immunomodulatory impact in macrophages polarization and inflammatory cytokine production, which could...
An amendment to this paper has been published and can be accessed via a link at the top of the pa... more An amendment to this paper has been published and can be accessed via a link at the top of the paper.
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