Final irrigation protocols affect radicular dentin DMP1-CT expression, microhardness, and biochemical composition

OBJECTIVE

To evaluate the effect of several final irrigation protocols on radicular dentin microhardness, biochemical composition, and DMP1-CT expression.

MATERIALS AND METHODS

A total of 140 single-rooted human teeth were prepared with WaveOne Gold files and randomly distributed into 7 groups (n = 20) according to the final irrigation protocol: distilled water (DW); sodium hypochlorite-EDTA (NaOCl-EDTA); EDTA (EDTA); EDTA-NaOCl (EDTA-NaOCl); EDTA-chlorhexidine (EDTA-CHX); passive ultrasonic irrigation (PUI:NaOCl-EDTA); and PUI:NaOCl-EDTA-NaOCl. Dentin microhardness (n = 10) was evaluated in the root canal lumen using Vickers hardness tester. Immunohistochemical analysis (n = 5) was used to evaluate DMP1-CT expression. Dentin ultrastructure and biochemical composition were evaluated by using Raman and energy dispersive X-ray analysis (EDAX) (n = 5) with a scanning electron microscope (SEM). Analysis of variance (ANOVA) and Tukey test were performed (p˂0.05).

RESULTS

Raman spectra of the organic content and DMP1-CT expression were lower at the lumen canal in EDTA-NaOCl, PUI:NaOCl-EDTA, and PUI:NaOCl-EDTA-NaOCl when compared to control (p < 0.05). EDAX showed reduced values for calcium and phosphorus in EDTA-NaOCl, PUI:NaOCl-EDTA, and PUI:NaOCl-EDTA-NaOCl. SEM microphotography's showed completely cleaned dentin, permeable tubules, and dentin erosion, mainly when PUI was used. NaOCl-EDTA presented significantly higher microhardness values than PUI:NaOCl-EDTA-NaOCl (p < 0.05). PUI:NaOCl-EDTA-NaOCl exhibited the lowest Vickers hardness values of all groups.

CONCLUSION

The final irrigation protocols that used a final rinse with NaOCl and PUI showed a detrimental effect on radicular dentin DMP1-CT expression, biochemical composition, and microhardness.

CLINICAL RELEVANCE

The adequate irrigation protocol could be advantageous to preserve the radicular dentin ultrastructure, promote adequate adhesion, and sustain favorable conditions for biomineralization and regeneration.

Comparison of Modified Triple Antibiotic Paste in Two Concentrations for Lesion Sterilization and Tissue Repair in Primary Molars: An In Vivo Interventional Randomized Clinical Trial

Introduction

"Lesion sterilization and tissue repair" (LSTR) is a non-instrumentation endodontic treatment modality that has recently gained popularity with promising results in several clinical trials. However, there is a dearth of evidence regarding the concentration of modified triple antibiotic paste (MTAP) to be used for the procedure.

Aim and objective

To compare the clinical and radiographic efficacy of 1 mg/mL and 1 g/mL concentrations of MTAP (ciprofloxacin, metronidazole, and clindamycin) used in LSTR of primary molars.

Materials and methods

Sixty-four infected primary molars in children between 4 years and 10 years of age were randomly allocated to two groups. Lesion sterilization and tissue repair at 1 mg/mL concentration of MTAP (group I) and 1 g/mL concentration of MTAP (group II) was performed. Clinical and radiographic outcomes were evaluated using Coll and Sadrian's criteria at 10 days, 1 month, and 3 months and the results were tabulated.

Statistical analysis

The data obtained were subjected to statistical analysis with IBM. SPSS statistics software 23.0 Version. To test the significance in categorical data, a Chi-square test was used. The probability value of 0.05 was considered significant.

Results

At the end of 3 months review, clinical success rates of group I and group II were 84.4 and 90.6%, respectively, and radiographic evaluation showed group I-78.1% and group II-90.6%.

Conclusion

Both 1 mg/mL and 1 g/mL concentrations of MTAP used in LSTR of primary molars had similar success rates with no statistically significant difference.

Clinical significance

Lesion sterilization and tissue repair when found to be equally effective in less concentration may aid in achieving adequate infection control with the least detrimental effect on the remaining vital pulp and periradicular structures. In addition, this circumvents the systemic administration of potent antibiotics thus combating antibiotic resistance.

How to cite this article

Shankar K, Ramkumar H, Dhakshinamoorthy S, et al. Comparison of Modified Triple Antibiotic Paste in Two Concentrations for Lesion Sterilization and Tissue Repair in Primary Molars: An In Vivo Interventional Randomized Clinical Trial. Int J Clin Pediatr Dent 2021;14(3):388-392.

The effect of changing apical foramen diameter on regenerative potential of mature teeth with necrotic pulp and apical periodontitis

OBJECTIVE

The aim of the present study was to evaluate the regenerative potential of permanent necrotic mature teeth with different apical foramen diameters in comparison to conventional endodontic treatment.

METHODS

Pulp necrosis and periapical pathosis were induced in premolars (144 roots) in six mongrel dogs. The infected teeth were divided into six groups; conventional root canal treatment (RCT) group prepared up to apical preparation sizes #F3 ProTaper file, regenerative endodontic therapy (RET) groups; groups RET-F3, RET-F4, and RET-F5 where regenerative endodontic procedures were applied after apical preparation up to sizes #F3, F4, and F5 ProTaper file, respectively, control groups; and positive (P) and negative (N) groups included infected and healthy teeth respectively. Each group (12 teeth with 24 roots each) was further subdivided into two subgroups (6 teeth with 12 roots each) according to the evaluation periods 1 and 3 months; each group was equally randomized in the upper and lower jaws during each evaluation period.

RESULTS

The inflammatory cell counts for the RCT group were statistically significantly higher than that of all RET groups at the first period and only significantly higher than RET-F5 at the second period. The enlargement of the apical foramen to #F5 showed no statistically significant difference with #F4 regarding the inflammatory cell count, tissue in-growth inside the root canal, and percentage of bone resorption. The tissue formed after RET was not true pulp tissue and is considered tissue repair with connective tissue, dilated blood vessels, and cementum-like structures.  CONCLUSION: Increasing the apical size diameter was associated with less inflammatory cell count, less percentage of bone resorption, more tissue ingrowth, and more percentage of new hard tissue formation inside root canal. The minimum apical diameter that should be enlarged for RET is 0.4 mm.

CLINICAL RELEVANCE

RET could be used as an alternative procedure to RCT for the treatment of mature teeth with necrotic pulp and apical periodontitis.

Management of internal inflammatory root resorption using injectable platelet-rich fibrin revascularization technique: a clinical study with cone-beam computed tomography evaluation

OBJECTIVES

The current study evaluated clinically and radiographically the management of internal inflammatory root resorption (IIRR) in permanent anterior teeth with or without periapical lesions using injectable platelet-rich fibrin (i-PRF) regenerative approach.

METHODS

Ten systemically healthy patients, with thirteen anterior mature teeth diagnosed with IIRR were selected for the study. At the first visit, the tooth was anesthetized, access cavity opened, root canals were mechanically prepared then medicated with calcium hydroxide and temporarily sealed. After 2-4 weeks, regenerative endodontic procedures were performed by preparing and applying i-PRF inside the canal, then a freshly prepared PRF membrane was placed over it. White mineral trioxide aggregate was placed over the PRF matrix, and the tooth was restored with a glass ionomer cement base and resin composite restoration. The patients were recalled for clinical and radiographic evaluation and follow-up every 3 months for 12 months. Cone-beam computed tomography (CBCT) imaging was performed preoperatively and after 12 months.

RESULTS

Clinical evaluation results showed resolution of signs and symptoms through the follow-up period in all of the cases. Both CBCT imaging readings of IIRR lesions and periapical lesions revealed a volumetric significant difference (p = 0.00) between the preoperative and the 12-month follow-up period.

CONCLUSIONS

Usage of i-PRF could arrest and allow for healing of IIRR in permanent mature teeth and allow for periapical healing with successful clinical results.

CLINICAL RELEVANCE

i-PRF revascularization technique proved to be a successful REP in the treatment of the IIRR, reducing the number of appointments and increasing patient compliance.

Antimicrobial Therapeutics in Regenerative Endodontics: A Scoping Review

INTRODUCTION

This review aimed to provide a critical appraisal of alternative antimicrobial strategies in lieu of traditional triple antibiotic paste (TAP).

METHODS

This review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. The literature search was performed in 8 databases (PubMed/Medline, Embase, LILACS, Web of Science, Scopus, BVS, SciELO, and the Cochrane Library), selecting clinical, in vitro, in vivo, and in situ studies that evaluated antimicrobial alternatives to TAP in regenerative endodontics. Studies lacking an experimental TAP group were excluded.

RESULTS

A total of 1705 potentially relevant records were initially identified. From the 38 studies retrieved for full-text reading, 16 fulfilled all selection criteria and were included in the qualitative analysis. According to the study design, 11 studies were solely in vitro, 1 study was both in vitro and in vivo (animal model), 2 studies were solely animal experiments, and 2 studies were clinical trials. The alternative antimicrobial agents to TAP consisted of modified TAP formulations (eg, a combination of TAP with chitosan); TAP-eluting nanofibers; propolis; chlorhexidine (CHX) gels/solutions; double antibiotic pastes composed of distinct combinations of antibiotics; Ca(OH)₂-based formulations; and sodium hypochlorite. Overall, most of the alternative agents performed similarly to TAP, although some strategies (eg, Ca(OH)₂- and CHX-based formulations) seemed to present dubious importance in the control of infection.

CONCLUSIONS

TAP still remains an excellent option in terms of the complete elimination of microorganisms. This review points to the use of electrospun fibers as a drug delivery system to offer a controlled release of the antimicrobial agent, as well as the use of natural compounds, deserving future investigation.

Assessment of Nitrofurantoin as an Experimental Intracanal Medicament in Endodontics

Background and Objectives. Multiple antibacterial agents have been mixed and used as an intracanal medicament-like modified triple antibiotic paste (MTAP) to eliminate Enterococcus faecalis (EF), which has been most frequently identified in the cases of failed root canal treatment and periapical lesions. This study is aimed at using a single antibacterial agent, nitrofurantoin (Nit), as an experimental intracanal medicament paste against different clinical isolates of EF), which has been most frequently identified in the cases of failed root canal treatment and periapical lesions. This study is aimed at using a single antibacterial agent, nitrofurantoin (Nit), as an experimental intracanal medicament paste against different clinical isolates of Materials and Methods. Three strains of EF), which has been most frequently identified in the cases of failed root canal treatment and periapical lesions. This study is aimed at using a single antibacterial agent, nitrofurantoin (Nit), as an experimental intracanal medicament paste against different clinical isolates of n = 90), group M (MTAP) (n = 90), group M (MTAP) (n = 90), group M (MTAP) (EF), which has been most frequently identified in the cases of failed root canal treatment and periapical lesions. This study is aimed at using a single antibacterial agent, nitrofurantoin (Nit), as an experimental intracanal medicament paste against different clinical isolates of n = 90), group M (MTAP) (n = 90), group M (MTAP) (n = 90), group M (MTAP) (EF), which has been most frequently identified in the cases of failed root canal treatment and periapical lesions. This study is aimed at using a single antibacterial agent, nitrofurantoin (Nit), as an experimental intracanal medicament paste against different clinical isolates of

Antimicrobial Activity and Physicochemical Properties of Antibiotic Pastes Used In Regenerative Endodontics

Abstract: The purpose of this study was to evaluate the pH, solubility and antimicrobial action of Calcium Hydroxide Paste (CH), Double Antibiotic Paste (metronidazole+ciprofloxacin-DAP), calcium hydroxide added to DAP (CH/DAP) and Triple Antibiotic Paste (metronidazole + ciprofloxacin+minocycline-TAP). pH (n=10) were measured by pHmeter. Root canals of acrylic teeth (n=10) were filled with the above-mentioned intracanal-dressings, immersed in ultrapure water, and solubility was measured by the difference between the initial and final volume (7,15 and 30 days) by using micro-computed tomography. Enterococcus faecalis biofilm was induced on bovine dentin disc surfaces (n=20), and treated with the pastes for 7 days. Percentage bacterial viability was verified by confocal microscope, with LIVE/DEAD dye. CH and CH/DAP presented the highest pH values. Regarding solubility, after 7 days, antibiotic groups presented significant volume loss. CH and CH/DAP showed no statistical difference compared with the Control in antimicrobial action against E. faecalis biofilm. However, TAP and DAP presented a significant percentage reduction in bacterial population. Due to high solubility of the pastes, renewing antibiotic dressings every 7 days, or using the medications for this period in regeneration protocols is recommended. DAP is indicated for killing E. faecalis in biofilm because it has antimicrobial action similar to TAP. Adding Calcium Hydroxide to DAP significantly decreased its antimicrobial action. In spite of its the low solubility and high pH values, the CH paste showed a low level of antimicrobial action against E. faecalis in biofilm.

Do different strains of E. faecalis have the same behavior towards intracanal medications in in vitro research?

The aim of this study was to evaluate the antimicrobial action of different endodontic pastes against Enterococcus faecalis ATCC 29212, isolated from the urinary tract, and compare the action with E. faecalis ATCC 4083, isolated from the root canal. For this purpose, dentin blocks were infected for 21 days with both bacteria at different time-intervals to ensure there would be no cross contamination. After this period, blocks were immersed in the test medications for 7 days, according to the following groups: CH/S, CH/P, CH/CMCP, CH/CHX, CH/DAP and TAP. Images of the samples were captured with a confocal microscope and the percentage of live cells was computed by means of the Bioimage program. The ATCC 29212 strain was shown to be more resistant to CH/SS, Calen, CH/DAP, and TAP than the ATCC 4083 strain. The antimicrobial action of the medications against each strain were divergent concerning the order of susceptibility. The authors concluded that the strains behaved in a different manner: in general, those extracted from the urinary tract were more resistant to the tested medications. Therefore, when E. faecalis must be used for in vitro research in endodontics, we suggest the use of ATCC 4083 strain to obtain results that are closer to the clinical reality.

Direct and indirect antibacterial effects of various concentrations of triple antibiotic pastes loaded in a methylcellulose system

We investigated the direct and indirect (residual) antibacterial effects of various concentrations of triple antibiotic paste (TAP) loaded into a methylcellulose system. Enterococcus faecalis (E. faecalis) was grown on sterilized dentin blocks (n = 60) and treated with clinically used TAP (1,000 mg/mL), low concentrations of methylcellulose-based TAP (100, 10, and 1 mg/mL), placebo paste, or 1.5% NaOCl (n = 10). The pastes were then removed, and biofilm disruption assays were performed. Additional dentin blocks (n = 120) were pretreated with the same experimental groups (n = 20). The pastes were rinsed off, and the samples were immersed independently in phosphate-buffered saline for 2 and 4 weeks (n = 10). E.faecalis was then grown on the dentin blocks, and biofilm disruption assays were performed. Fisher's Exact and Wilcoxon rank sum tests were used for statistical analyses. With regard to direct antibacterial effects, all treatment groups demonstrated complete eradication of biofilms in comparison to placebo paste, while 10 mg/mL of TAP or higher provided substantial residual antibacterial effects. However, dentin treated with 1 mg/mL of TAP or 1.5% NaOCl did not provide substantial residual antibacterial effects. Dentin pretreated with 10 mg/mL of TAP or higher exhibited extended residual antibacterial effects and can thus be used during endodontic regeneration.(J Oral Sci 58, 575-582, 2016).