Atypical healing of an endodontic lesion following emergency treatment: a case report.

This case report examines the atypical healing of an endodontic lesion without standard endodontic treatment, influenced by the patient's failure to attend treatment appointments. A 50-year-old woman with no notable medical history presented with a deep carious lesion on her mandibular right first molar, accompanied by localized pain. Citing forgetfulness as a reason, the patient missed her initially scheduled root canal treatment, necessitating an emergency intervention. The emergency treatment included access cavity preparation, irrigation with 5.25% sodium hypochlorite solution, application of a modified triple antibiotic paste (equal parts penicillin G, metronidazole, and ciprofloxacin), and temporary restoration with amalgam. A large apical lesion was detected in immediate postoperative radiographs. However, the patient failed to return for definitive endodontic treatment, due to a lack of symptoms and time for treatment. Follow-up examinations 1 and 5 years after emergency treatment disclosed gradual healing of the lesion, culminating in the establishment of a normal periodontal ligament. This case underscores the potential efficacy of a modified triple antibiotic paste and highlights the importance of a well-sealed coronal restoration in promoting the healing of endodontic lesions, even in the absence of pulpectomy and conventional root canal therapy. Additional research is needed to understand the mechanisms behind such healing events.

Examining the Effects of Asiaticoside on Dental Pulp Stem Cell Viability and Proliferation: A Promising Approach to Root Canal Treatment.

AIM: This study aims to evaluate the impact of asiaticoside (AC) on the viability and proliferation of dental pulp stem cells (DPSCs), considering the known negative effects of routinely used intracanal medicaments. This evaluation will be compared with the outcomes from using traditional intracanal medicaments, specifically triple antibiotic paste (TAP) and calcium hydroxide [Ca(OH)2]. MATERIALS AND METHODS: The DPSCs were obtained from the third molars of an adult donor. The application of flow cytometry was employed to do a phenotypic analysis on DPSCs using CD90, CD73, CD105, CD34, CD14, and CD45 antibodies. The methylthiazol tetrazolium (MTT) assay was employed to assess cellular viability. The cells were treated with different concentrations of TAP and Ca(OH)2 (5, 2.5, 1, 0.5, and 0.25 mg/mL), along with AC (100, 50, 25, 12.5, and 6.25 µM). A cell proliferation rate was performed at 3, 5, and 7 days. RESULTS: The characterization of DPSCs was conducted by flow cytometry analysis, which verified the presence of mesenchymal cell surface antigen molecules (CD105, CD73, and CD90) and demonstrated the absence of hematopoietic markers (CD34, CD45, and CD14). Cells treated with concentrations over 0.5 mg/mL of TAP and Ca(OH)2 showed a notable reduction in cell viability in comparison to the untreated cells (p < 0.05). Additionally, the cells treated with different concentrations of AC 12.5, 6.25, 25, and 50 µM did not differ significantly from the untreated cells (p > 0.05). Nevertheless, cells treated with concentrations of 100 µM showed a significant reduction in viability compared to the untreated cells (p < 0.05). After a period of 7 days, it was noted that cells exposed to three different concentrations of AC (50, 25, and 12.5 µM) had a notable rise in cell density in comparison to TAP and Ca(OH)2 (p < 0.05). Furthermore, cells that were exposed to a concentration of 12.5 µM exhibited the highest cell density. CONCLUSION: The cellular viability of the AC-treated cells was superior to that of the TAP and Ca(OH)2-treated cells. Moreover, the AC with a concentration of 12.5 µM had the highest degree of proliferation. CLINICAL SIGNIFICANCE: This study underscores the importance of evaluating alternative root canal medicaments and their effects on DPSCs' growth and vitality. The findings on AC, particularly its influence on the survival and proliferation of DPSCs, offer valuable insights for its probable use as an intracanal medication. This research contributes to the ongoing efforts to identify safer and more effective intracanal treatments, which are crucial for enhancing patient outcomes in endodontic procedures. How to cite this article: Alazemi MJ, Badawi MF, Elbeltagy MG, et al. Examining the Effects of Asiaticoside on Dental Pulp Stem Cell Viability and Proliferation: A Promising Approach to Root Canal Treatment. J Contemp Dent Pract 2024;25(2):118-127.

The Effect of Rosmarinus Officinalis as a Potential Root Canal Medication on the Viability of Dental Pulp Stem Cells.

AIM: The objective of the current study was to assess and compare the impact of triple antibiotic paste (TAP) and calcium hydroxide (Ca(OH)2) with rosmarinic acid (RA) on the viability of dental pulp stem cells (DPSCs). MATERIALS AND METHODS: Dental pulp stem cells were isolated and characterized using flow cytometry. The cells were treated with (0.25, 0.5, 1, 2.5, and 5 mg/mL) concentrations for TAP and Ca(OH)2 and (6.25, 12.5, 25, 50, and 100 µM) concentrations for RA. Cell viability was evaluated after 3 days, with cell proliferation further analyzed over 3, 5, and 7 days utilizing the MTT assay. The optical density (OD) was quantified at 570 nm, subsequently enabling the determination of corrected OD and cell viability. ANOVA followed by the post hoc Tuckey test evaluated the statistical significance at p < 0.05. RESULTS: Following the cell viability test, 0.25 and 0.5 mg/mL of TAP and Ca(OH)2 showed no significant difference for DPSCs compared to the control group. While dosages of 1 mg/mL, 2.5 mg/mL, and 5 mg/mL significantly reduced cell viability (p < 0.05). However, 6.25 µM and 12.5 µM concentrations of RA showed a significant increase in cell viability compared to untreated cells, 25 µM and 50 µM concentrations showed no significant difference compared to untreated cells while 100 µM concentration showed a decrease in cell viability (p < 0.05). Moreover, RA at a concentration of 12.5 µM exhibited a significant enhancement in cell proliferation rates after 5 and 7 days. CONCLUSION: Rosmarinic acid showed a significant increase in cell viability when used at 6.25 and 12.5 µM concentrations compared to TAP and CA(OH)2. CLINICAL SIGNIFICANCE: The assessment of cytotoxicity associated with bioactive compounds like RA, which processes antimicrobial and anti-inflammatory properties, holds importance. This evaluation could pave the way for novel intracanal medicaments that enhance the regenerative potential of DPSCs.

Effect of Boswellic Acid on Viability of Dental Pulp Stem Cells Compared to the Commonly Used Intracanal Medications: An In Vitro Study.

AIM: This study was aimed at evaluating the effect of acetyl-11-keto-ß-boswellic acid (AKBA) on dental pulp stem cells (DPSCs) viability and proliferation to be used as a potential root canal medicament. MATERIALS AND METHODS: Dental pulp stem cells were isolated from human third molars. The phenotypic characterization of DPSCs was verified by flow cytometry analysis. The viability assay was performed using the methyl-thiazoltetrazolium (MTT) assay. Cells were treated with different concentration of triple antibiotic paste (TAP) and calcium hydroxide Ca(OH2) (5, 2.5, 1, 0.5, and 0.25 mg/mL), AKBA (10, 5, 1, 0.1, and 0.01 µM). All experiments were done in separate triplicate experiments. Results: Dental pulp stem cells were characterized by flow cytometry. Cells treated with Ca(OH)2 (1, 2.5, and 5 mg/mL) showed significantly reduced viability compared with the control cells (p < 0.05). Dental pulp stem cells treated with 1, 2.5, and 5 mg/mL TAP resulted in a significant decrease in viability (p < 0.05). Cells treated with AKBA in concentrations (1, 0.1, and 0.01 µM) demonstrated higher viability than the control group (p < 0.05), while AKBA in concentrations (5 and 10 µM) showed equal or decreased viability than the control group. (p > 0.05). Regarding cell density assay, AKBA showed significant increase in cell density after 5 and 7 days compared with cells medicated with TAP and Ca(OH)2 while TAP revealed marked reduction in cell density in all the tested intervals. CONCLUSION: Acetyl-11-keto-ß-boswellic acid in lower concentrations (0.01, 0.1, and 1 µM) demonstrated superior cell viability than TAP and Ca(OH)2, and it may possess the potential to be an intracanal medicament in regenerative endodontics. CLINICAL SIGNIFICANCE: Studying the effect of different potential root canal medicaments and their capability to induce DPSCs proliferation might be of value. The influence of AKBA on the viability and proliferation of DPSCs tested in this study sheds light on its use as a potential intracanal medication especially in regenerative endodontics. How to cite this article: Amer NA, Badawi MF, Elbeltagi MG, et al. Effect of Boswellic Acid on Viability of Dental Pulp Stem Cells Compared to the Commonly Used Intracanal Medications: An In Vitro Study. J Contemp Dent Pract 2023;24(12):957-966.

Effects of an Nd:YAP laser used for root canal disinfection in pulp regenerative therapy: a pilot study.

This study aimed to compare the disinfection effects between a triple antibiotic paste and neodymium-doped yttrium aluminum perovskite (Nd:YAP) laser in pulp regenerative therapy and evaluate corresponding therapeutic effects based on apical radiographs and cone-beam computed tomography (CBCT). Sixty-six immature permanent teeth in 66 patients diagnosed with acute or chronic apical periodontitis were analyzed. All teeth were given pulp regenerative therapy. The patients were categorized into a control (triple antibiotic paste) and an experimental (Nd:YAP laser) group. Teeth in the experimental group were disinfected using an Nd:YAP laser, while those in the control group were disinfected using a triple antibiotic paste. Clinical and radiological examinations were performed every 3-6 months after treatment and followed up for 24 months. Statistical analysis was performed after clinical examination and showed that after one week of treatment, symptoms persisted in two teeth in the control group and two teeth in the experimental group. Two weeks later, the clinical symptoms disappeared in all teeth (p > 0.05). After 24 months of follow-up, the clinical symptoms recurred in two teeth in the control group and one tooth in the experimental group. On radiographic examination, 31 and 27 teeth showed continued root development, and three and two teeth showed no obvious root development in the control and experimental groups, respectively. The pulp sensibility test was positive in four teeth in both groups, with no significant difference between the two groups (p > 0.05). The results of this study suggest that endodontic irradiation with an Nd:YAP laser could be an effective alternative to triple antibiotic paste during disinfection of pulp regenerative therapy. Treatment outcomes were assessed using apical radiographs and CBCT, and no negative prognostic effects of the Nd:YAP laser on pulp regenerative therapy were found.

Silver Nanoparticles Alone or in Combination with Calcium Hydroxide Modulate the Viability, Attachment, Migration, and Osteogenic Differentiation of Human Mesenchymal Stem Cells.

This study aimed to evaluate the effect of silver nanoparticles (AgNPs) alone or in combination with calcium hydroxide (Ca(OH)2) on the proliferation, viability, attachment, migration, and osteogenic differentiation of human mesenchymal stem cells (hMSCs). Different concentrations of AgNPs alone or mixed with Ca(OH)2 were prepared. Cell proliferation was measured using AlamarBlue, and hMSCs attachment to dentin disks was evaluated using scanning electron microscopy. Live-dead imaging was performed to assess apoptosis. Wound healing ability was determined using the scratch-migration assay. To evaluate osteogenic differentiation, the expression of Runt-related transcription factor (RUNX2), Transforming growth factor beta-1 (TGF-ß1), Alkaline Phosphatase (ALP), and Osteocalcin (OCN) were measured using real-time reverse transcriptase polymerase chain reaction. ALP staining and activity were also performed as indicators of osteogenic differentiation. AgNPs alone seemed to favor cell attachment. Lower concentrations of AgNPs enhanced cell proliferation. AgNP groups showed markedly less apoptosis. None of the medicaments had adverse effects on wound closure. The expression of TGF-ß1 was significantly upregulated in all groups, and OCN was highly expressed in the AgNP groups. AgNPs 0.06% showed the most enhanced ALP gene expression levels, activity, and marked cytochemical staining. In conclusion, AgNPs positively affect hMSCs, making them a potential biomaterial for various clinical applications.

Management of an infected immature tooth with a talon cusp using regenerative endodontic treatment: A case report.

OBJECTIVE: Regenerative endodontic treatment (RET) has been considered a successful approach to manage infected immature teeth; however, cases associated with dental anomalies, i.e., talon cusp, need to be further investigated. CASE REPORT: A 7-year-old girl with local swelling associated with the permanent maxillary right central incisor was referred; cone-beam computed tomography revealed a talon cusp, an immature root and two well-defined endodontic lesions. The treatment consisted of regenerative endodontic treatment (RET); the canal was chemically cleaned and a modified triple antibiotic paste was used as intracanal medication. In the next appointment, RET was performed through the creation of blood clot scaffold in the canal covered/sealed with calcium-enriched mixture (CEM) cement. RESULTS: In the 7-day recall session, clinical examination showed that the swelling had completely resolved. At 24-month recall, the treated tooth was asymptomatic and functional. CBCT images demonstrated evidence of maturation in the apical third of the root, healing of two large endodontic lesions and complete dentinal bridge formation beneath CEM cement. CONCLUSION: RET for an infected immature tooth with a dental anomaly, i.e., talon cusp, may be a desirable treatment option and result in the resolution of endodontic lesions as well as regeneration of new vital tissues; allowing continuous root maturation.

Host defense peptide IDR-1002 associated with ciprofloxacin as a new antimicrobial and immunomodulatory strategy for dental pulp revascularization therapy.

Regenerative therapies such as dental pulpal revascularization appear as an option for traumatized immature permanent teeth. However, the triple antibiotic paste - TAP (metronidazole, minocycline, and ciprofloxacin), used for these therapies, can generate cytotoxicity and dentin discoloration. In contrast, host defense peptides (HDPs) are promising antimicrobial and immunomodulatory biomolecules for dentistry. This study aimed to evaluate in vitro the antimicrobial activity (against Staphylococcus aureus and Enterococcus faecalis) and the immunomodulatory potential (by the evaluation of IL-1α, IL-6, IL-12, IL-10, TNF-α and NO, in RAW 264.7 macrophages and IL-6, TGF-ß and NO, in L929 fibroblast) of synthetic peptides (DJK-6, IDR-1018, and IDR-1002), compared to TAP in an in vitro infection model containing heat-killed antigens from E. faecalis and S. aureus. Furthermore, the synergistic potential of ciprofloxacin and IDR-1002 was evaluated by checkerboard. Ciprofloxacin was the best antimicrobial of TAP, besides acting in synergism with IDR-1002. TAP was pro-inflammatory (p < 0.05), while the association of ciprofloxacin and IDR-1002 presented an anti-inflammatory profile mainly in the presence of both heat-killed antigens (p < 0.05). Based on these results, ciprofloxacin associated with IDR-1002 may demonstrate an efficient antimicrobial and immunomodulatory action in this in vitro model. Further in vivo studies may determine the real potential of this combination.

Antimicrobial and immunomodulatory in vitro profile of double antibiotic paste.

AIM: To evaluate the antimicrobial and immunomodulatory activity of double antibiotic paste (DAP) in an in vitro infection model. METHODOLOGY: The minimum inhibitory and bactericidal concentrations (MIC and MBC) and the antibiofilm activities (TTC assay) of DAP and its components (ciprofloxacin and metronidazole) were evaluated against Staphylococcus aureus and Enterococcus faecalis compared with triple antibiotic paste (TAP). The cellular viability of RAW 264.7 macrophages (24 and 72 h) and L929 fibroblasts (48 and 72 h) was evaluated by MTT. Furthermore, the production of TNF-α, IL-12, IL-6, IL-1α, IL-10 and NO (on RAW 264.7), besides IL-6, TGF-ß and NO (on L929), stimulated with DAP in baseline and associated with heat-killed microbial-antigen conditions was measured by ELISA and Griess reaction. Data were analysed using the one-way ANOVA test with Bonferroni's corrections. RESULTS: The MBC of pharmacopoeia DAP was similar to TAP for E. faecalis (0.25 µg.  mL-1 ) and lower for S. aureus (DAP 1 µg. mL-1 and TAP 2 µg. mL-1 ; p < .001). Ciprofloxacin was the most effective antibiofilm drug from the pastes (35% of reduction for E. faecalis and S. aureus; p < .0001), and both pastes had a similar antibiofilm eradication against both biofilm species (29% and 35% for S. aureus and 76% and 85% for E. faecalis; p < .0001). DAP was cytotoxic against the tested cells. DAP significantly upregulated IL-1α (p < .001), IL-6 (p < .0001), TNF-α (p < .01) and IL-12 (p < .05; in the absence of antigens) and significantly reduced IL-6 (p < .0001; in the presence of HK-S. aureus) and IL-10 (p < .05; in the presence of both antigens) on macrophages. Furthermore, DAP upregulated IL-6 (p < .001) and NO (p < .05; in the absence of antigens), IL-6 (p < .001; in the presence of HK-S. aureus) and reduced NO (p < .001; in the presence of HK-S. aureus). CONCLUSIONS: Double antibiotic paste and TAP had similar antimicrobial activity against S. aureus and E. faecalis. DAP upregulated pro-inflammatory cytokines mainly in the absence of antigens and had pro- and anti-inflammatory activity in RAW 264.7 macrophages and L929 fibroblasts in the presence of antigens involved in pulp infections.

The effect of intracanal medicaments used in Endodontics on the dislocation resistance of two calcium silicate-based filling materials.

BACKGROUND: Intracanal medicaments can be used in various endodontic conditions including multiple visit endodontics after trauma or in regenerative endodontics. These medicaments should be removed from the root canal before the placement of the filling or repair material. The aim of the present study was to evaluate the effect of prior calcium hydroxide (Ca(OH)2) and modified triple antibiotic paste (mTAP) placement on the push-out bond strength of TotalFill BC fast set putty (BC fast set putty) to root dentin when compared to mineral trioxide aggregate (MTA). METHODS: The root canals of 45 extracted mandibular premolars were prepared to a standardized internal diameter (1.5 mm). The specimens were randomly assigned to 3 groups according to the intracanal medicament used: mTAP (a mixture of metronidazole, ciprofloxacin, and cefaclor), Ca(OH)2, and no intracanal medicament. After 1 week, the medicaments were removed, and the middle third of the roots were cut into two transverse sections (2.0 ± 0.05) (n = 90 slices). Thereafter, the specimens were divided into two subgroups (n = 45 each): MTA or BC putty. After 1 week, the push-out test was performed and failure mode was evaluated. The data were statistically analyzed using two-way ANOVA and Tukey's post hoc. RESULTS: The application of the intracanal medicament did not significantly affect the bond strength of BC putty (p > .05). For MTA, the prior application of Ca(OH)2 or mTAP significantly decreased the dislocation resistance (p < .05). Specimens in the MTA subgroups showed an almost equal number of cohesive and mixed types of failure while the majority of the specimens in the BC putty subgroups revealed the cohesive type. CONCLUSIONS: Ca(OH)2 and mTAP promoted lower bond strength of MTA to root dentin compared to the control group. However, the BC fast set putty bond strength to dentin was not affected by prior medication with Ca(OH)2 or mTAP.

Effect of Intracanal Medicaments (Modified Triple Antibiotic Paste, Calcium Hydroxide, and Aloe Vera) on Microhardness of Root Dentine: An In Vitro Study.

AIM: To compare the effect of three different intracanal medicaments, namely, modified triple antibiotic paste (MTAP), calcium hydroxide (Ca(OH)2), and aloe vera, on the root dentine microhardness. MATERIALS AND METHODS: A total of 50 extracted mandibular bicuspids were prepared using ProTaper Next rotary files. The roots of the bicuspids were alienated to three groups (n = 10 each) and one control group (untreated; n = 20). In three groups, the root canals were filled with MTAP, Ca(OH)2, and aloe vera medicaments. After 21 days, medicaments were removed by Endo activator. Mean Knoop hardness numbers were calculated after treatment and compared with the untreated control group. Data were evaluated using the Student's t test (paired), ANOVA (one-way) followed, and the post hoc test. RESULTS: All treated groups except the aloe vera group had shown significant reduction (p < 0.05) in microhardness of the root dentin as compared with the untreated control group. The aloe vera group showed least reduction of microhardness and was statistically insignificant (p > 0.05). CONCLUSION: Aloe vera shows promising results in terms of fewer effects on microhardness of the root dentin compared to MTAP and Ca(OH)2. CLINICAL SIGNIFICANCE: Elimination of most of the bacterial infection from the root canal and very minimum to no effect on the microhardness of the dentin in the root part are the basics of success in any endodontic treatment. Further in vivo studies are required to compare the efficacy of these intracanal medicaments.

Effect of Different Intracanal Medicaments on Apical Sealing Ability of BioRoot RCS.

AIMS AND OBJECTIVES: The aim of the present study was to determine the effect of different intracanal medicaments on the apical seal of BioRoot root canal sealer (RCS). MATERIALS AND METHODS: One hundred permanent single-rooted teeth were used in this study. All the samples were decoronated at the cementoenamel junction and instrumented in a sequential order from 15 to 50 number k-file. The specimens were randomly divided into five groups containing 20 teeth each. Intracanal medicaments used in this study were Metapex, triple antibiotic paste, Metrogyl DG gel forte (metronidazole gel 1.5% w/w), and curenext gel. For control group following instrumentation, the roots were obturated with laterally compacted gutta-percha with BioRoot RCS. In medicament groups after the period of 14 days, the medicaments were removed. All the four groups were obturated with BioRoot RCS and gutta-percha cones using lateral compaction technique. All the specimens were coated with nail varnish and immersed in 2% methylene blue. Then the specimens were demineralized and diphanized. The cleared teeth were analyzed by means of a stereomicroscope under 10× magnification. All the data were analyzed in SPSS version 18 software (IBM, Chicago, IL, USA). RESULT: Among all the intracanal medicaments, triple antibiotic paste showed the highest microleakage. When Metpaex and Metrogyl DG gel forte were compared with Curcuma longa, differences were not statistically significant. CONCLUSION: Among all the intracanal medicaments, triple antibiotic paste showed the highest microleakage and least was Metapex. CLINICAL SIGNIFICANCE: Incomplete removal of medicaments prevents the penetration of sealer into the dentinal tubules and interferes with the normal setting reaction, thus affecting the seal of obturating material leading to microleakage and subsequent treatment failure. Hence, while placing an intracanal medicament, it is important to consider its effect on leakage of the root canal system.

Ability of two single-step restorative materials to avoid crown darkening caused by intracanal minocycline paste.

OBJECTIVES: This study aimed to quantitatively assess the ability of two single-step restorative materials to avoid crown darkening caused by the use of minocycline as an intracanal medicament. MATERIALS AND METHODS: After coronal access and instrumentation, 120 maxillary incisors were divided into four groups (n = 30). Two experimental groups according to the restorative material applied to the inner walls of the access cavity: OB, OptiBond All-In-One + minocycline intracanal paste; U200, RelyX U200 + minocycline intracanal paste. Two control groups without restorative materials: MIN, minocycline intracanal paste and SL, saline intracanal. Color determination was performed using a spectrophotometer at five time points, immediately after materials were applied (baseline), and at 7, 14, 21, and 28 days from the baseline. RESULTS: Decrease in the mean values of L* (luminosity) was observed after insertion of minocycline paste in all groups at all time points. Statistically significant differences were absent between the time points (P > .05). After 28 days, MIN showed significantly more darkening (ΔL*) (- 10.6 ± 7.3) than OB (- 5.4 ± 6.2), U200 (- 5.8 ± 3.9) and SL (- 2.3 ± 1.2) (P < .05). CONCLUSIONS: Crown darkening can be minimized by the previous application of RelyX U200 or OptiBond All-In-One to the inner walls of the access cavity before a minocycline-containing paste is applied as an intracanal medication. CLINICAL RELEVANCE: The American Association of Endodontists Clinical Considerations for Regenerative Procedures in necrotic immature teeth suggests the triple antibiotic paste as an intracanal medication (2018). However, discoloration and crown darkening are common unfavorable outcomes. The clinical protocol suggested in this paper has shown to be able to minimize crown darkening, predictably leading to a better patient-centered clinical success.

Evaluation of the preventive efficacy of three dentin tubule occlusion methods against discoloration caused by triple-antibiotic paste.

The aim of this in vitro study was to evaluate the preventive efficacy of three dentin tubule occlusion methods against discoloration caused by triple-antibiotic paste (TAP). Sixty extracted human incisors were sectioned, and the access was opened. The specimens were randomly allocated to the following four groups (n = 15): bonding application (BD), teethmate desensitizer (TM), Nd:YAG laser application (LS), and no surface treatment (control, C). Specimens were discolored with TAP over a period of 3 weeks. The color was measured by spectrophotometry at two time-points: initially and after 3 weeks of TAP placement. Color differences (∆E) were calculated and analyzed. Discoloration was visually noticed in all teeth after 3 weeks. The differences between the control group and the three dentin tubule occlusion methods were statistically significant (p < 0.05); however, there were no statistically significant differences among the BD, TM, and LS groups (p > 0.05).

Evaluation of antibacterial activity of propolis on regenerative potential of necrotic immature permanent teeth in dogs.

BACKGROUND: This study evaluated the antibacterial efficiency and ability of propolis to promote regeneration of immature permanent non-vital dogs' teeth. METHODS: Ninety six immature permanent premolars teeth in 6 mongrel dogs were divided randomly into: experimental teeth (N = 72) and control teeth (N = 24). Periapical pathosis was induced in all experimental and positive control teeth. Experimental teeth were classified according to the used intra-canal medication into: group I (N = 36), propolis paste was used and group II (N = 36), triple antibiotic paste (TAP) was used. Bacteriologic samplings were collected before and after exposure to intra-canal medicaments. After the disinfection period (3 weeks), revascularization was induced in all experimental teeth. Each group was subdivided according to the root canal orifice plug into: subgroup A (N = 18), propolis paste was used and subgroup B (N = 18), mineral trioxide aggregates (MTA) was used. Each subgroup was further subdivided according to the evaluation period into 3 subdivisions (6 teeth each): subdivision 1; after 2 weeks, subdivision 2; after one month and subdivision 3; after 2 months. Positive control group had 12 teeth with induced untreated periapical pathosis. Negative control group had 12 untouched sound teeth. All teeth were evaluated with radiography and histology. The bacteriologic and radiographic data were analyzed using repeated measures ANOVA and post-hoc Tukey tests. The histologic data were analyzed using Kruskal-Wallis test, Mann-Whitney U test with Bonferroni's adjustment and Chi-square test. The significance level was set at P ≤ .05. RESULTS: There was no significant difference in the antibacterial effectiveness between TAP and propolis groups (P > .05). In all subdivisions, there was no significant difference between the experimental groups in terms of increase in root length and dentin thickness, decrease in apical closure, new hard tissue formation, vital tissue formation inside the pulp canal and apical closure scores (P > .05). CONCLUSION: Propolis can be comparable with TAP as a disinfection treatment option in regenerative endodontic. As a root canal orifice plug after revascularization of necrotic immature permanent teeth in dogs, propolis induces a progressive increase in root length and dentin thickness and a decrease in apical diameter similar to those of MTA.

Effectiveness and clinical implications of the use of topical antibiotics in regenerative endodontic procedures: a review.

Regenerative endodontic procedures (REPs) are biologically based procedures planned to replace damaged tissues, including dentinee and root structures, as well as cells of the pulp-dentine complex. Effective sterilization of the root canal is essential in REPs, and antibiotics have been widely used to disinfect root canals. The aim of this paper was to review the scientific literature on (i) Effectiveness of antibiotics used in REPs against bacteria implicated in endodontic disease; (ii) Scientific evidence supporting the use of topical antibiotics in REPs; (iii) Clinical implications of the use of antibiotics in REPs and the possible side effects; (iv) Effect of antibiotics on dental pulp stem cells; and (v) Ongoing research on the use of antibiotics in REPs. Antibiotics used in REPs are effective against bacteria implicated in endodontic infections. Triple antibiotic pastes with minocycline attain complete disinfection of immature teeth with necrotic pulps, without affecting SCAP. Experimental studies carried out in dogs support the use of antibiotics in REPs. Clinical studies report high success rates of RET using antibiotics as intracanal dressings. However, tooth discolouration is an important side effect of the use of TAP. An antibiotic paste containing only metronidazole and ciprofloxacin could be a good alternative to the use of TAP. The use of antibiotic-containing scaffolds or clindamycin-modified triple antibiotic (metronidazole, ciprofloxacin and clindamycin) polymer could be a biologically safe antimicrobial drug delivery system in REPs.

Revascularization in Immature and Mature Teeth with Necrotic Pulp: A Clinical Study.

AIM: The aim of this in vivo study was to evaluate the revascularization procedure both in immature and mature teeth with necrotic pulp and open apices, disinfected with triple antibiotic paste followed by inducing blood clot in the root canal. MATERIALS AND METHODS: Fifteen patients were selected who presented with immature and mature permanent teeth with pulpal necrosis and open apices. In the first visit, the root canal was accessed with LA and rubber dam isolation; then the canal was disinfected using triple antibiotic paste containing ciprofloxacin, metronidazole, and clindamycin in the ratio of 1:1:1 and closed with IRM. In the second visit, after administering local anesthesia and isolating with a rubber dam, the triple antibiotic paste was washed out by saline irrigation, and apical papilla beyond the confines of the root canal was stimulated with sterile H file to produce a blood clot. Finally, the access was closed using a double seal with mineral trioxide aggregate (MTA) placed apical to cementoenamel junction and resin bonded cement over the MTA. Radiographic examination and pulp sensibility test was done during the follow-up period of 2,4,6,8 and 10 months. RESULT: After 10 months follow-up, 10 out of 13 patients showed root development and apical closure. The eight patients out of 13 showed root development, apical closure and lateral thickening of radicular dentin and 2 out of 13 patients showed a positive response to electric sensibility test. CONCLUSION: Within the limitation of this study, it can be concluded that there is evidence of root development, increase in lateral wall thickness, apical closure and positive response to pulp sensibility test in both mature and immature teeth with necrotic pulp. CLINICAL SIGNIFICANCE: The conventional approach for management of teeth with necrotic pulp and the open apex is altered with the possibility of tissue regeneration within the pulp space and continued root development through revascularization procedures. It also re-establishes the vitality in a previously nonvital and necrosed tooth.

The efficiency of different irrigation solutions and techniques for the removal of triple antibiotic paste from simulated immature root canals.

INTRODUCTION: The purpose of this study was to evaluate the efficiencies of different irrigation protocols in the removal of triple antibiotic paste (TAP) from root canals. MATERIALS AND METHODS: A total of 127 extracted human maxillary incisor teeth were prepared. Then, root-end resection of 3 mm was accomplished to simulate immature apex model. The root canals were filled with TAP, after 21 days, randomly divided into nine groups according to irrigation systems and solutions (n = 13). Conventional irrigation (CI) groups - Group 1: Root canal irrigation was performed with CI by Peracetic acid (PAA) solution, Group 2: Root canal irrigation was performed with CI by etidronic acid 1-hydroxyethylidene-1, 1-bisphosphonate (HEBP) + sodium hypochlorite (NaOCl) solution, Group 3: Root canal irrigation was performed with CI by ethylenediaminetetraacetic acid (EDTA)/NaOCl solutions. Vibringe system groups - Group 4: Root canal irrigation was performed with Vibringe system by PAA solution, Group 5: Root canal irrigation was performed with Vibringe system by HEBP + NaOCl solution, Group 6: Root canal irrigation was performed with Vibringe system by EDTA/NaOCl solution. EndoVac system groups - Group 7: Root canal irrigation was performed with EndoVac system by PAA solution, Group 8: Root canal irrigation was performed with EndoVac system by HEBP + NaOCl solution, Group 9: Root canal irrigation was performed with EndoVac system by EDTA/NaOCl solution. Control Group: (n = 0). Samples were sectioned vertically, and the amount of remaining medicament was scored for each root half and data were statistically analyzed. RESULTS: Among the irrigation systems, CI groups showed the highest scores at both apical and coronal parts (P < 0.05). In comparisons among the solutions, at the apical part, PAA groups showed the highest scores (P < 0.05). At the coronal part, EDTA + NaOCl groups showed the lowest score values (P < 0.05). CONCLUSION: The use of irrigation systems improved the removal of TAP from the simulated immature root canals. Also, as an irrigation solution EDTA gives more promising results than PAA and HEBP solutions.

Attachment and proliferation of dental pulp stem cells on dentine treated with different regenerative endodontic protocols.

AIM: To investigate the attachment and proliferation of dental pulp stem cells (DPSC) on dentine treated with various endodontic regeneration protocols. METHODOLOGY: Standardized dentine samples were irrigated with sodium hypochlorite (1.5% NaOCl) and ethylenediaminetetraacetic acid (17% EDTA) and randomized into four treatment groups and two control groups. The treatment groups were treated with a clinically used concentration of triple antibiotic paste (TAP), double antibiotic paste (DAP), calcium hydroxide (Ca(OH)2 ) or diluted TAP in a methylcellulose system (DTAP) for 1 week. Each sample in the treatment groups was then irrigated with EDTA. The two control groups were treated with EDTA or received no treatment. Dental pulp stem cells were seeded on each dentine specimen (10 000 cells). Lactate dehydrogenase activity assays were then performed to evaluate the attached DPSC after 1 day of incubation. Water-soluble tetrazolium assays were used to determine DPSC proliferation after three additional days of incubation. Friedman's test followed by least significant difference were used for statistical analyses (α = 0.05). RESULTS: Triple antibiotic paste and DTAP regeneration protocols, as well as EDTA-treated dentine, caused significant increases in DPSC attachment to dentine. Triple antibiotic paste, DAP and Ca(OH)2 regeneration protocols caused significant reductions in DPSC proliferation on dentine. However, the DTAP regeneration protocol did not have any significant negative effects on DPSC proliferation. CONCLUSIONS: The clinically used endodontic regeneration protocols that include the use of TAP, DAP or Ca(OH)2 medicament negatively affected DPSC proliferation on dentine. However, the use of DTAP medicament during regenerative endodontic treatment may not adversely affect the proliferation of DPSC.

Effect of triple antibiotic paste with or without ethylenediaminetetraacetic acid on surface loss and surface roughness of radicular dentine.

This study aimed to compare the effect of two concentrations of triple antibiotic paste (TAP) with or without ethylenediaminetetraacetic acid (EDTA) on surface loss and surface roughness of radicular dentine. Human radicular dentine specimens were randomized into six experimental groups (n = 16 per group). The first and second groups were treated with 1,000 mg/mL or 1 mg/mL of TAP for 4 weeks. The third and fourth groups were treated with 1,000 mg/mL or 1 mg/mL of TAP for 4 weeks followed by 17 % EDTA for 5 min. The fifth group was treated with 17 % EDTA for 5 min and the sixth group received no treatment (control). Dentine surface loss and surface roughness were quantified after various treatments using optical and contact profilometry, respectively. One-way ANOVA followed by Fisher's protected least significant differences was used for statistical analyses. All treatment groups showed significantly higher surface loss compared to the untreated dentine. Dentine treated with 1,000 mg/mL had significant increase in surface loss and surface roughness compared to dentine treated with 1 mg/mL of TAP. The use of EDTA after both concentrations of TAP did not have significant additive effect on surface loss and surface roughness of dentine. The clinically used concentration of TAP (1,000 mg/mL) caused significantly higher surface loss and surface roughness of radicular dentine compared to the use of 1 mg/mL of TAP. Furthermore, the substantial amount of dentine surface loss and surface roughness detected in the current study may be attributed to TAP rather than EDTA.