Pulp-dentin Regeneration Cao, Y.; Song, M.; Kim, E. ...
Journal of Dental Research,
11/2015, Letnik:
94, Številka:
11
Book Review, Journal Article
Recenzirano
The goal of regenerative endodontics is to reinstate normal pulp function in necrotic and infected teeth that would result in reestablishment of protective functions, including innate pulp immunity, ...pulp repair through mineralization, and pulp sensibility. In the unique microenvironment of the dental pulp, the triad of tissue engineering would require infection control, biomaterials, and stem cells. Although revascularization is successful in resolving apical periodontitis, multiple studies suggest that it alone does not support pulp-dentin regeneration. More recently, cell-based approaches in endodontic regeneration based on pulpal mesenchymal stem cells (MSCs) have demonstrated promising results in terms of pulp-dentin regeneration in vivo through autologous transplantation. Although pulpal regeneration requires the cell-based approach, several challenges in clinical translation must be overcome—including aging-associated phenotypic changes in pulpal MSCs, availability of tissue sources, and safety and regulation involved with expansion of MSCs in laboratories. Allotransplantation of MSCs may alleviate some of these obstacles, although the long-term stability of MSCs and efficacy in pulp-dentin regeneration demand further investigation. For an alternative source of MSCs, our laboratory developed induced MSCs (iMSCs) from primary human keratinocytes through epithelial-mesenchymal transition by modulating the epithelial plasticity genes. Initially, we showed that overexpression of ΔNp63α, a major isoform of the p63 gene, led to epithelial-mesenchymal transition and acquisition of stem characteristics. More recently, iMSCs were generated by transient knockdown of all p63 isoforms through siRNA, further simplifying the protocol and resolving the potential safety issues of viral vectors. These cells may be useful for patients who lack tissue sources for endogenous MSCs. Further research will elucidate the level of potency of these iMSCs and assess their transdifferentiation capacities into functional odontoblasts when transplanted into the root canal microenvironment.
Pulp-dentin Regeneration Cao, Y; Song, M; Kim, E ...
Journal of dental research,
11/2015, Letnik:
94, Številka:
11
Journal Article
Recenzirano
The goal of regenerative endodontics is to reinstate normal pulp function in necrotic and infected teeth that would result in reestablishment of protective functions, including innate pulp immunity, ...pulp repair through mineralization, and pulp sensibility. In the unique microenvironment of the dental pulp, the triad of tissue engineering would require infection control, biomaterials, and stem cells. Although revascularization is successful in resolving apical periodontitis, multiple studies suggest that it alone does not support pulp-dentin regeneration. More recently, cell-based approaches in endodontic regeneration based on pulpal mesenchymal stem cells (MSCs) have demonstrated promising results in terms of pulp-dentin regeneration in vivo through autologous transplantation. Although pulpal regeneration requires the cell-based approach, several challenges in clinical translation must be overcome—including aging-associated phenotypic changes in pulpal MSCs, availability of tissue sources, and safety and regulation involved with expansion of MSCs in laboratories. Allotransplantation of MSCs may alleviate some of these obstacles, although the long-term stability of MSCs and efficacy in pulp-dentin regeneration demand further investigation. For an alternative source of MSCs, our laboratory developed induced MSCs (iMSCs) from primary human keratinocytes through epithelial-mesenchymal transition by modulating the epithelial plasticity genes. Initially, we showed that overexpression of ΔNp63α, a major isoform of the p63 gene, led to epithelial-mesenchymal transition and acquisition of stem characteristics. More recently, iMSCs were generated by transient knockdown of all p63 isoforms through siRNA, further simplifying the protocol and resolving the potential safety issues of viral vectors. These cells may be useful for patients who lack tissue sources for endogenous MSCs. Further research will elucidate the level of potency of these iMSCs and assess their transdifferentiation capacities into functional odontoblasts when transplanted into the root canal microenvironment.
Background
Development of a standardized set of topic‐specific outcomes known as a Core Outcome Set (COS) is important to address issues of heterogeneity in reporting research findings in order to ...streamline evidence synthesis and clinical decision making.
Aim
The aim of the current international consensus study is to identify “what” outcomes to include in the Core Outcome Set for Endodontic Treatments (COSET). Outcomes of various endodontic treatments (non‐surgical root canal treatment, surgical endodontics, vital pulp treatment and revitalization procedures) performed on permanent teeth were considered.
Methods
A standard validated methodology for COS development and reporting was adopted. The process involved identification of existing outcomes through four published scoping reviews. This enabled creation of a list of outcomes to be prioritized via semi‐structured patient interviews, e‐Delphi process and a consensus meeting with a range of relevant global stakeholders. Outcomes were prioritized using a 1–9 Likert scale, with outcomes rated 7–9 considered critical, 4–6 are important and 1–3 are less important. Outcomes rated 7–9 by ≥70% and 1–3 by <15% of participants were considered to achieve consensus for inclusion in the COS. The outcomes that did not achieve consensus in the first round were considered for further prioritization in the second Delphi round and consensus meeting. Final decisions about the outcomes to include in COSET were made by voting during the consensus panel meeting using the Zoom Poll function.
Results
A total of 95 participants including patients contributed to the COS development process. The consensus panel recommended, with strong consensus, eight outcomes shared across all treatment modalities for inclusion in COSET: pain; signs of infection (swelling, sinus tract); further intervention/exacerbation; tenderness to percussion/palpation; radiographic evidence of disease progression/healing; function; tooth survival; and patient satisfaction. Additional treatment specific outcomes were also recommended.
Discussion
Many of the outcomes included in COSET are patient reported. All should be included in future outcomes studies.
Conclusion
COSET identified outcomes that are important for patients and clinicians and validated these using a rigorous methodology. Further work is ongoing to determine “how” and “when” these outcomes should be measured.
Pulpal and periradicular diseases are primarily caused by bacterial invasion of the root canal system as a result of caries progression. The presence of residual bacteria at the time of root canal ...completion (obturation) is associated with significantly higher rate of treatment failure. Re-infection of obturated root canals can be potentially prevented by enhancing the antibacterial activities of root canal obturation materials. We evaluated, in an in vitro model, the antimicrobial efficacy of silver ions added to a common endodontic sealer. For that purpose we performed growth inhibition studies and bacterial viability tests. We measured the zone of inhibition, optical density and performed confocal laser scanning microscopy. Our results show that the silver ions enhance the antimicrobial activity of the root canal sealer against Streptococcus mutans. This study approach may hold promise for studying other biologically based therapies and therefore increasing the success rate of routine orthograde root canal treatment.
Objective: Many biological variables, endodontic treatment factors, and restorative considerations have been suggested in the literature to affect the outcome of endodontic treatment. However, few ...attempts have been made recently to study these variables further. The purpose of this study was to identify the biologic and endodontic treatment-associated variables that are most predictive of treatment outcome for conventional endodontic therapy and to determine the magnitude of risk these variables pose on the outcome. Study Design: The population of this historical prospective cohort study comprised a total of 200 teeth with 441 root canals. Diagnostic and treatment information was abstracted from the original patient records. An endodontic follow-up examination was conducted 4 ± 0.5 years after obturation. Each tooth/root was analyzed according to 3 indices of periradicular status at 2 time points. The main outcome measure was the presence of apical periodontitis. The criteria used for evaluation of the outcome were modified from Strindberg. Data were subjected to univariate and multivariate analysis. Logistic regression models were fit by using various clinical measures to determine which combination of biologic and treatment-associated factors best predicted treatment outcome. Results: The preoperative pulp diagnosis, the periapical diagnosis, the preoperative periapical radiolucency size, and the sex of the patients were revealed, by means of univariate analysis, to exert a significant influence on endodontic treatment outcome (P < .05). In the logistic regression model, the strongest effect on postoperative healing was the presence and magnitude of preoperative apical periodontitis. In the presence of this variable, no other factor contributed value to the prediction. The correct prediction of this model was 74.7% (P < .05). Conclusion: The major biologic factors influencing the outcome of endodontic treatment appear to be the extent of microbiological insult to the pulp and periapical tissue, as reflected by the periapical diagnosis and the magnitude of periapical pathosis.(Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2001;91:342-52)
We sought to investigate the simultaneous effect of apical periodontitis, instrumentation level, and density of root canal filling on endodontic treatment outcome.
For this study, 200 endodontically ...treated teeth with 441 roots were used. A follow-up examination was conducted 4 ± 0.5 years postoperatively. Data were subjected to univariate and multivariate analysis.
Periapical pathosis had the strongest effect on treatment outcome (
P <.0001). The instrumentation level (mean ± SEM of the working length) for successfully treated teeth/roots with normal preoperative pulp and periapex was farther away from the radiographic apex (1.23 ± 0.13mm) than for teeth/roots with an unsuccessful outcome (0.20 ± 0.09mm;
P <.005). However, successfully treated teeth/roots with pulp necrosis and apical periodontitis had working length levels closer to the radiographic apex (0.55 ± 0.12 mm) than did teeth/roots with unsuccessful outcomes (1.73 ± 0.30mm;
P<.001). In teeth/roots with apical periodontitis, a millimeter loss in working length increased the chance of treatment failure by 14%. The risk of failure was higher for a fair/poor density of obturation than for a good density for all diagnoses of periradicular status.
Diseased periapex, level of working length relative to the radiographic apex, and fair/poor density all affect the outcome of endodontic treatment.
Increased interleukin-8 expression in inflamed human dental pulps Huang, George T.-J.; Potente, Anthony P.; Kim, Jang-Wook ...
Oral surgery, oral medicine, oral pathology, oral radiology and endodontics,
08/1999, Letnik:
88, Številka:
2
Journal Article, Conference Proceeding
Recenzirano
Objective. Elevated levels of interleukin-8, a potent chemoattractant and activator of neutrophils, are associated with infectious and inflammatory diseases. However, little is known about ...interleukin-8 expression in human dental pulp. The purpose of this study was to determine whether tissue levels of interleukin-8 are elevated in irreversibly inflamed human pulps.
Study design. Experimental samples were from teeth clinically diagnosed with irreversible pulpitis (diseased pulps). Controls were from freshly extracted, caries-free third molars (normal pulps). Samples were subjected to enzyme-linked immunosorbent assay and/or immunohistochemical analysis with specific antibodies to interleukin-8.
Results. The enzyme-linked immunosorbent assay studies showed elevated levels of interleukin-8 in diseased pulps (mean, 1.82 ± 0.79 pg/mL/μg protein), as compared to detectable interleukin-8 levels in samples from normal pulps (mean, 0.08 ± 0.04 pg/mL/μg protein;
P < .05). Immunohistochemical analyses demonstrated that diseased samples exhibited a higher density of localized interleukin-8 staining in areas with heavy infiltration of inflammatory cells. In contrast, normal pulps showed negative or weak interleukin-8 staining.
Conclusions. Interleukin-8 concentration was higher in pulps diagnosed with irreversible pulpitis; only negligible amounts of interleukin-8 were present in normal pulps.
(Oral Surg Oral Med Oral Pathol Oral Radiol Endod 1999;88:214-20)
Objective: The multifunctional cytokine interleukin-6 (IL-6) has actions on multiple cell types, including promotion of the development of immune cells and osteoclasts. Periapical inflammation as the ...result of root canal infection is characterized by the accumulation of inflammatory cells and bone resorption. The effect of IL-6 on periapical lesion formation after pulpal infection is unknown. We sought to determine whether deletion of IL-6 affects periapical lesion formation after pulp exposure. Methods: Molar pulps of homozygous IL-6 knock-out mice (IL-6–/–, strain B6, 129-Il6tm1Koe ) and wild-type mice (IL-6+/+) were exposed, and the mice were killed at 1, 2, 3, 5, and 8 weeks after the exposure. Mouse jaws were decalcified and prepared for histologic examination of periapical lesions. Results: The IL-6–/– mice developed larger periapical lesions more rapidly than did the IL-6+/+ mice. Conclusions: IL-6 deletion promoted periapical lesion development.(Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2001;92:83-8)
The purpose of this study was to develop a reproducible, quantitative model of
Candida albicans adhesion to human dentin through the use of a colorimetric method and to evaluate the effect of smear ...layer on candidal adhesion.
Dentin disks with or without smear layer were incubated with
C albicans (10
8 cells/mL) for 4 hours. After incubation, the disks were exposed to an (2,3)-bis(2-methoxy-4-nitro-5-sulfophenyl)-5-(phenylamino)-carbonyl-2
H-tetrazolium hydroxide–coenzyme Q solution for 2 hours. The color of (2,3)-bis(2-methoxy-4-nitro-5-sulfophenyl)-5-(phenylamino)-carbonyl-2
H-tetrazolium hydroxide formazan in the supernatant was determined spectrophotometrically at 492 nm. To relate formazan formation to cell numbers, standard curves were generated with known numbers of yeast cells without dentin. The number of adherent cells per square millimeter was then calculated.
The number of attached
C albicans cells was 2.4 × 10
4 per square millimeter in dentin with smear layer and 1.5 × 10
4 in dentin without smear layer (
P < .05).
(2,3)-Bis(2-methoxy-4-nitro-5-sulfophenyl)-5-(phenylamino)-carbonyl-2
H-tetrazolium hydroxide assay is a potential microbiologic tool for the quantitative determination of
Candida adhesion to human dentin.
PDF
