Intermediate Restorative Material Research Articles

Prognostic Factors Affecting the Outcome of Surgical Root Canal Treatment-A Retrospective Cone-Beam Computed Tomography Cohort Study.

Aim: To assess the association between demographic and clinical variables and the outcome of root-end surgery using digital periapical radiographs (PA) and cone-beam computed tomography (CBCT). Methodology: One hundred and fifty teeth that received endodontic microsurgery were clinically and radiographically examined (PA and CBCT scans) after 1 and 2 years. Two calibrated endodontists evaluated the radiographic healing based on a six-point outcome classification. The outcome was classified using both strict (healed) and loose (healing) criteria. The success rates were calculated, and several outcome prognostic factors were assessed. Results: One hundred and fifty teeth were assessed with both radiographic systems. When "loose" success criteria were applied using PA, 90% (n = 135) of teeth were assessed as having had a favourable outcome (90%; 95% CI: 85.2-94.8%), whereas 90.7% (n = 136) of teeth showed a successful outcome when assessed with CBCT (90.7%; 95% CI: 86.0-95.3%). When "strict" success criteria were applied, there was a statistically significant difference (p = 0.018) between the success rates of mineral trioxide aggregate (MTA) (63.7%) and Biodentine (95.5%). Conclusions: Within the limitations of this study, endodontic microsurgery showed a high success rate. Among all the demographic and clinical variables assessed, in the multiregression analysis, only the use of Biodentine was associated with a higher proportion of "complete" healings compared to MTA or Intermediate Restorative Material (IRM) when assessed using CBCT. MTA and Biodentine performed similarly when "incomplete" healings were regarded as successful outcomes.

Hard tissue formation in pulpotomized primary teeth in dogs with nanomaterials MCM-48 and MCM-48/hydroxyapatite: an in vivo animal study

BackgroundThis animal study sought to evaluate two novel nanomaterials for pulpotomy of primary teeth and assess the short-term pulpal response and hard tissue formation in dogs. The results were compared with mineral trioxide aggregate (MTA).MethodsThis in vivo animal study on dogs evaluated 48 primary premolar teeth of 4 mongrel female dogs the age of 6–8 weeks, randomly divided into four groups (n = 12). The teeth underwent complete pulpotomy under general anesthesia. The pulp tissue was capped with MCM-48, MCM-48/Hydroxyapatite (HA), MTA (positive control), and gutta-percha (negative control), and the teeth were restored with intermediate restorative material (IRM) paste and amalgam. After 4–6 weeks, the teeth were extracted and histologically analyzed to assess the pulpal response to the pulpotomy agent.ResultsThe data were analyzed using the Kruskal‒Wallis, Fisher’s exact, Spearman’s, and Mann‒Whitney tests. The four groups were not significantly different regarding the severity of inflammation (P = 0.53), extent of inflammation (P = 0.72), necrosis (P = 0.361), severity of edema (P = 0.52), extent of edema (P = 0.06), or connective tissue formation (P = 0.064). A significant correlation was noted between the severity and extent of inflammation (r = 0.954, P < 0.001). The four groups were significantly different regarding the frequency of bone formation (P = 0.012), extent of connective tissue formation (P = 0.047), severity of congestion (P = 0.02), and extent of congestion (P = 0.01). No bone formation was noted in the gutta-percha group. The type of newly formed bone was not significantly different among the three experimental groups (P = 0.320).ConclusionMCM-48 and MCM-48/HA are bioactive nanomaterials that may serve as alternatives for pulpotomy of primary teeth due to their ability to induce hard tissue formation. The MCM-48 and MCM-48/HA mesoporous silica nanomaterials have the potential to induce osteogenesis and tertiary (reparative) dentin formation.

Antibacterial Activity of Root Repair Cements in Contact with Dentin-An Ex Vivo Study.

This study assessed the antibacterial characteristics of the dentin/material interface and dentin surfaces exposed to experimental hydraulic calcium silicate cement (HCSC) with or without bioactive glass (BG) replacement (20% or 40%) or mixed with a silver nanoparticle (SNP) solution (1 or 2 mg/mL), and Biodentine, TotalFill BC RRM putty and Intermediate Restorative Material (IRM). Human root dentin segments with test materials were assessed at 1 or 28 days. In one series, the specimens were split to expose the dentin and material surfaces. A 24 h direct contact test was conducted against three-day established Enterococcus faecalis and Pseudomonas aeruginosa monospecies biofilms. In another series, the dentin/material interface of intact specimens was exposed to biofilm membranes for 3 days and the antibacterial activity was assessed via confocal microscopy. The interface was additionally characterised. All one-day material and dentin surfaces were antibacterial. Dentin surfaces exposed to HCSC with 40% BG-replacement, Biodentine and IRM had decreased antibacterial properties compared to those of the other cements. The HCSC mixed with a 2 mg/mL SNP solution had the highest antimicrobial effect in the confocal assay. The interfacial characteristics of HCSCs were similar. The test materials conferred antibacterial activity onto the adjacent dentin. The BG reduced the antibacterial effect of dentin exposed to HCSC; a 2 mg/mL SNP solution increased the antibacterial potential for longer interaction periods (three-day exposure).

Effect of exposure conditions on chemical properties of materials for surgical endodontic procedures.

This study investigated the role of aging and changes in environmental conditions on selected properties of a prototype radiopacified calcium silicate-based cement (TZ-base) with or without incorporation of silver nanoparticles or bioactive glass, and two commercial materials, Biodentine and intermediate restorative material. Materials were immersed in ultrapure water or fetal bovine serum for 28 days and were characterized with scanning electron microscopy and energy dispersive x-ray analysis. Immersion media were either replaced weekly or not replenished at all and were assessed for alkalinity and calcium release after 1, 7, 14, 21, and 28 days; antibacterial effect against 2-day monospecies biofilms; and cytotoxicity by the 3-(4,5 dimethylthiazolyl-2-yl)-2,5-diphenyl tetrazolium bromide assay after 1, 7, or 28 days. Alkalinity, calcium release, antibacterial activity, and cell cytotoxicity increased over time when the medium was not changed but decreased with medium replenishment. Immersion in fetal bovine serum resulted in lower alkalinity, less bactericidal properties, and lower cytotoxicity of prototype cements and Biodentine than did water immersion. Biodentine and 20% bioactive glass-containing cement had overall lower alkalinity, calcium release, and antibacterial activity than TZ-base, and Biodentine was less cytotoxic than TZ-base. In conclusion, exposure conditions and cement modifications significantly affected materials' leaching properties. Exposure conditions warrant consideration when evaluating cements' clinical properties.

Biocompatibility, bioactive potential, porosity, and interface analysis calcium silicate repair cements in a dentin tube model.

This study is to evaluate biocompatibility, bioactive potential, porosity, and dentin/material interface of Bio-C Repair (BIOC-R), MTA Repair HP (MTAHP), and Intermediate Restorative Material (IRM). Dentin tubes were implanted into subcutaneous of rats for 7, 15, 30, and 60days. Thickness of capsules, number of inflammatory cells (ICs), interleukin-6 (IL-6), osteocalcin (OCN), and von Kossa were evaluated. Porosity and material/dentin interface voids were also analyzed. Data were submitted to ANOVA and Tukey's tests (p < 0.05). IRM capsules were thicker and contained greater ICs and IL-6-immunopositive cells at 7 and 15days. BIOC-R capsules exhibited higher thickness and ICs at 7days and greater IL-6 at 7 and 15days than MTAHP (p < 0.05). At 30 and 60days, no significant difference was observed among the groups. OCN-immunopositive cells, von Kossa-positive, and birefringent structures were observed in BIOC-R and MTAHP. MTAHP exhibited higher porosity and interface voids (p < 0.05). BIOC-R, MTAHP, and IRM are biocompatible. Bioceramics materials demonstrate bioactive potential. MTAHP presented the highest porosity and presence of voids. BIOC-R and MTAHP have adequate biological properties. BIOC-R demonstrated lower porosity and presence of voids, which may represent better sealing for its clinical applications.

Fracture resistance and fracture modes in endodontically treated maxillary premolars restored using different CAD-CAM onlays.

To examine the fracture resistance and fracture modes of endodontically treated teeth (ETT) restored using onlays of different materials fabricated using computer-aided design and computer-aided manufacturing (CAD-CAM). Sixty maxillary first premolars were randomly assigned to six groups (n=10). The first group comprised intact teeth (INT). The remaining premolars were prepared for mesio-occluso-distal cavity and root canal treatments. Group 2 was treated using polymer-reinforced zinc oxide-eugenol intermediate restorative material (IRM). Groups 3-6 were core build-up, prepared for onlay, and restored using resin nanoceramic (Cerasmart [CER]), polymer-infiltrated ceramic networks (Vita Enamic [VE]), lithium disilicate-based ceramic (IPS e.max CAD [EM]), or translucent zirconia (Katana Zirconia UTML [KZ]). All specimens were immersed in 37 °C distilled water for 24 h. Each specimen was loaded at 45° to the long axis until failure (crosshead speed, 0.5 mm/min). Fracture loads were analyzed using one-way analysis of variance and Tukey's post-hoc test (α=0.05). There were no significant differences in fracture load among the INT, CER, VE, and EM groups. The fracture load in the KZ group was significantly higher than those in the other groups (P < 0.05). Fracture load was the lowest in the IRM group (P < 0.05). The unrestorable failure rate was 70% in the KZ group and 10-30% in the other experimental groups. ETT restored using Cerasmart, Vita Enamic, or IPS e.max CAD onlays had fracture resistance and patterns comparable to those of intact teeth. Katana Zirconia UTML-restored ETT had the highest fracture load but also a higher unrestorable failure rate.

Effect of different indirect composite onlay and core materials on fracture resistance of endodontically treated maxillary premolars.

Purpose To compare and evaluate the effects of different indirect composite onlay and/or core buildup materials on the fracture resistance and fracture mode of restored endodontically treated premolars.Methods Two conventional handmade indirect composite resins (SR Nexco (NC) and Ceramage (CM)) and two core buildup materials, dual-cure composite resin (MultiCore Flow (MC)), and short fiber-reinforced composite resin (EverX Posterior (EXP)), were selected. Sixty maxillary premolars were randomly divided into six groups (n=10). Group 1 included intact teeth (INT; positive control). Mesio-occluso-distal cavity preparation and endodontic treatment was performed on the remaining premolars. Group 2 was restored with polymer-reinforced zinc oxide eugenol intermediate restorative material (IRM; negative control), whereas the experimental groups (groups 3-6) were restored with core buildup material and indirect composite onlay (MC_NC, MC_CM, EXP_NC, and EXP_CM). The specimens received compressive loading using a universal testing machine, at 45° to the long axis with a crosshead speed of 0.5 mm/min until fracture. Fracture modes were visually analyzed. Fracture resistance was measured and statistically analyzed using two-way and one-way ANOVA (α=0.05).Results Only the type of indirect composite onlay affected the fracture resistance of the experimental groups (P=0.009). The MC_CM group showed the highest fracture resistance, which was significantly higher than that of the MC_NC group (P=0.031). No statistically significant differences were found between the INT group and other experimental groups(P>0.05). All groups had a greater incidence of restorable than unrestorable failures.Conclusions The type of indirect composite onlay affected the fracture resistance of restored endodontically treated maxillary premolars.

Comparative Evaluation of Microleakage in Class II Restorations Using Open- and Closed-Sandwich Techniques With Zirconomer as an Intermediate Material: An In-Vitro Study.

Aim To evaluate and compare the microleakage In class II restorations using open- and closed-sandwich techniques with zirconomer as an intermediate material. Material and method Twenty-six non-carious mandibular first molars were selected and randomly divided into two groups (groups 1 and 2 where n=13). A standardized Class II preparation was made with the cervical margin 1 mm below the cementum-enamel junction. Samples of group 1 were restored using the open-sandwich technique and samples of group 2 with the close-sandwich technique, and zirconomer was used as an intermediate restorative material. Following that, the restorations underwent 200 heat cycles with dwell times of 20 seconds at 5°C and 55°C. Dye penetration and scanning electron microscope (SEM) analysis using the replica approach were used to assess adaptation at the cervical margin.The data were statistically analyzed using the Paired T-test(p<0.05). Results Lower dye penetration was seen in the open-sandwich technique compared to the closed-sandwich technique (p<0.001). Conclusion When comparing the open-sandwich technique with the closed one, it was observed that less microleakage was seen in the open-sandwich technique as it has better marginal adaptation and fewer voids.

Surface characteristics and bacterial adhesion of endodontic cements

ObjectivesTo investigate the effect of inclusion of silver nano-particles (SNP) or bioactive glass (BG) on the surface characteristics and bacterial adhesion of prototype tricalcium silicate (TCS)–based cements alongside two commercial cements, under different aging periods and exposure conditions.Materials and methodsA basic formulation of radio-opacified TCS without (TZ-base) and with additions of SNP (0.5, 1, or 2 mg/ml) or BG (10 or 20%) was used. Biodentine and intermediate restorative material (IRM) served as reference materials. Material disks were immersed in ultrapure water or fetal bovine serum (FBS) for 1, 7, or 28 days. Surface roughness (n = 3), microhardness (n = 9), and wettability (n = 6) were analyzed by standard procedures. Adhesion of Enterococcus faecalis was assessed by fluorescence microscopy (n = 5). Data from these assays were evaluated for normality and comparisons among groups were conducted with statistical procedures (p < 0.05 for significance).ResultsThe surface morphology of SNP- and BG-containing cements had higher roughness values than TZ-base after 28 days (p < 0.05). No differences in microhardness were observed among prototype cements (p > 0.05). Biodentine presented smooth surface characteristics and the highest hardness values (p < 0.05). The FBS-immersion resulted in surface reactions in prototype materials and Biodentine, depicted with scanning electron microscopy. All 1- and 7-day prototype cements showed negligible bacterial adhesion, while in Biodentine and IRM, noticeable E. faecalis adherence was observed from day 1 (p < 0.05).ConclusionsIncorporation of SNP or BG did not improve the antibacterial effect of the experimental cement; all 28-day aged materials failed to inhibit bacterial adherence. The measured physical parameters did not appear to be related to the degree of bacterial adhesion. Exposure of TCS-based cements in FBS resulted in surface reactions, which did not affect bacterial adhesion.Clinical relevanceChanges in the surface characteristics of prototype TCS-based cements by inclusion of SNP and BG or exposure to different environments did not affect bacterial adhesion. All experimental materials showed inferior physical properties and higher antibacterial effect than Biodentine.

Management of intrinsic discoloration in maxillary incisors with the walking bleach: A case report

In the age of minimally invasive dentistry and increasing aesthetic demands, walking bleach is the most effective and conservative method. Hydrogen peroxide is one of the commonly used bleaching agent. This case report illustrates the walking bleach technique in maxillary incisors with hydrogen peroxide.A 35 years old female reported with discoloured endodontically treated maxillary incisors. Retreatment of maxillary incisors followed by walking bleach was planned. Glass ionomer cement was used as a barrier material. 35% hydrogen peroxide was placed in the pulp chamber with intermediate restorative material. The procedure was repeated after 5 days to achieve the desired results.35% hydrogen peroxide can successfully bleach discolored endodontically treated teeth.Walking bleach technique is an incredibly effective approach for discolored intact non -vital teeth. It is rapid and easy to obtain desired results as well as economical to patients as compared to crowns and veneers.

Antimicrobial evaluation of polytetrafluoroethylene used as part of temporary restorations: An ex vivo study.

The use of polytetrafluoroethylene (PTFE) tape as the base layer of temporary restorations had gained popularity mainly due to the ease of manipulation. The aim of this study was to assess whether this method changes the potential for bacterial growth and leakage of temporary restorations. The direct contact test and live/dead fluorescent staining were used for comparing Enterococcus faecalis growth and biofilm formation on PTFE, composite, intermediate restorative material (IRM) and Coltosol F. Confocal laser scanning microscopy was employed to evaluate E.faecalis penetration through 2mm of PTFE, IRM or Coltosol F placed on the bottom of the pulp chamber and into radicular dentinal tubules in extracted maxillary third molars. The results demonstrated that E.faecalis grows on and penetrates through PTFE significantly more than it does with IRM and Coltosol F, revealing its comparably reduced overall antimicrobial sealing ability when placed as the base part of temporary restorations.

Comparison of Dentinal Microleakage in Three Interim Dental Restorations: An In Vitro Study.

The aim of this study was to assess and compare the coronal microleakage of e-Temp (DiaDent, Korea), intermediate restorative material (IRM) (Dentsply, Sirona), and Systemp Inlay (Ivoclar Vivadent, Germany) temporary restorative materials used to seal the class I cavity preparations. In this in vitro experimental study, three temporary restorative materials were assessed for microleakage. A standardized class I access cavities (2 mm × 4 mm) were prepared in 30 freshly extracted intact human premolar teeth. Teeth were then divided randomly into three groups consisting of 10 samples each. Teeth were restored with e-Temp (n = 10), IRM (n = 10), and Systemp Inlay (n = 10), temporary restorations, and subjected to thermocycling 5000 times in a cold bath followed by a temperature of 55°C with a dwell time of 30 seconds. Teeth were painted with two layers of nail polish except for 1 mm around the restoration margin, soaked in 1% methylene blue dye solution (pH 7.4), and kept for 24 h. Sticky wax was used to seal the apical foramina. All the teeth were sectioned mesiodistally, and the specimens were examined for the amount of dye penetration (microleakage) through the restoration using Digital Microscope under 50× magnification. Data were analyzed using descriptive statistics, Mann-Whitney U, and Kruskal-Wallis tests. e-Temp showed 1 (10%) specimen with dye penetration up to 1 mm (Score 1). The specimens restored with IRM showed a 1 (10%) and 9 (90%) of scores for 1 and 3 dye penetration. However, 2 (20%) teeth restored with Systemp Inlay showed a dye penetration up to 3 mm or more (Score 3). A comparison of mean microleakage values of e-Temp (0.03 ± 0.10), IRM (2.69 ± 0.77), and Systemp Inlay (0.78 ± 1.64) showed a statistically significant difference (P < 0.001). IRM specimens showed significantly higher microleakage values than e-Temp and Systemp Inlay specimens (P < 0.05). All the temporary restorative materials tested in this in vitro experiment showed a certain extent of microleakage. The temporary restorative material e-Temp showed the least microleakage values followed by Systemp Inlay and IRM.

Ex Vivo Evaluation of Bacterial Leakage and Coronal Sealing Capacity of Six Materials in Endodontically Treated Teeth.

Successful endodontic treatment requires an effective coronal sealing to prevent the penetration of saliva and microorganisms into the root canal system. We aimed to investigate the sealing capacity of Maxxion R, Intermediate Restorative Material (IRM), Mineral Trioxide Aggregate-like material (Biodentine), White Cimpat, Flow Resin and Z250 Resin against Enterococcus (E.) faecalis infiltrates, when used as coronal sealants after endodontic treatment. Sixty-six roots of adult lower premolars were randomly divided into 6 experimental groups with 10 roots each (n=10), and two control groups (positive and negative) with three roots each. The root canals were instrumented to ProTaper F3 file, irrigated with 2.5% NaOCl and 17% EDTA, and filled using Tagger's Hybrid technique with AH-Plus cement. After removing 2 mm of the coronal third filling with a Gates Glidden #6 drill, the cervical portion of each of the sixty roots was sealed with a 2 mm-thick plug, plus the respective material being tested in this study. All roots were fitted to silicone devices (Eppendorf) with cut extremities and sterilized with ethylene oxide; experimental procedures were performed in a laminar flow chamber for aseptic chain maintenance. All specimens were inoculated with E. faecalis, and the culture medium was renewed every 3 days for 60 days. Medium turbidity was evaluated daily. The obtained data were subsequently submitted to analysis of variance (ANOVA-R) complemented by Student's t-test at a significance level of 5%. Analyzes of variance were calculated using the SAS system GLIMMIX procedure. Biodentine (56.90), Z250 Resin (54.90) and White Cimpat (53.30) resisted contamination for a longer time compared to Maxxion R (51.30), Flow Resin (50.70), and IRM (48.70) over a period of 60 days. Biodentine, Resin Z 250 and White Cimpat presented the lowest infiltration averages when compared to the other tested materials.

How do imaging protocols affect the assessment of root-end fillings?

ObjectivesThis study investigated the impact of micro-computed tomography (micro-CT)-based voxel size on the analysis of material/dentin interface voids and thickness of different endodontic cements.Materials and MethodsFollowing root-end resection and apical preparation, maxillary premolars were filled with mineral trioxide aggregate (MTA), Biodentine, and intermediate restorative material (IRM) (n = 24). The samples were scanned using micro-CT (SkyScan 1272; Bruker) and the cement/dentin interface and thickness of materials were evaluated at voxel sizes of 5, 10, and 20 µm. Analysis of variance and the Tukey test were conducted, and the degree of agreement between different voxel sizes was evaluated using the Bland and Altman method (p < 0.05).ResultsAll materials showed an increase in thickness from 5 to 10 and 20 µm (p < 0.05). When evaluating the interface voids, materials were similar at 5 µm (p > 0.05), while at 10 and 20 µm Biodentine showed the lowest percentage of voids (p < 0.05). A decrease in the interface voids was observed for MTA and IRM at 20 µm, while Biodentine showed differences among all voxel sizes (p < 0.05). The Bland-Altman plots for comparisons among voxel sizes showed the largest deviations when comparing images between 5 and 20 µm.ConclusionsVoxel size had an impact on the micro-CT evaluation of thickness and interface voids of endodontic materials. All cements exhibited an increase in thickness and a decrease in the void percentage as the voxel size increased, especially when evaluating images at 20 µm.

Assessment of Coronal Microleakage of Different Temporary Restorative Materials Used for Endodontic Access Cavity Restoration

Introduction: Complete sealing of the endodontic access cavity between appointments and after completion of therapy is a vital element in the successful outcome of endodontic treatment. A common concern in day to day dental practice of conservative dentistry and endodontics is coronal leakage. Such a complication often leads to the failure of endodontic treatment. The intention of this in vitro study was to assess the potentiality of three different temporary restorative materials (TRM) in preventing microleakage in the coronal aspect of the access cavity during inter-appointment period in the course of endodontic treatment. Methods: Zinc oxide eugenol, Intermediate restorative material (IRM) (Dentsply Sirona) and CAVIT were the three materials used in the study. A total of 60 premolar teeth extracted for orthodontic purposes were collected (n=20). Endodontic access cavity was prepared and restored with temporary restorative material in the respective groups. The teeth were stored under methylene blue stain and were sectioned to be observed under stereo microscope at 1,2,4,7,10 days. The coronal microleakage was scored and the outcome was interpreted using Mann Whitney U test. Results: On the 1st and 2nd day, every material showed significant statistical difference in microleakage scoring. Zinc oxide eugenol showed the maximum and excessive microleakage. But after the 4th day, the difference in microleakage scores did not show significant statistical variation. Conclusion: The outcome indicated that the mixing ratio of powder and liquid for zinc oxide eugenol plays a prime role in coronal microleakage. Nevertheless, none of the materials could prevent coronal microleakage for a long period. Therefore, it is better to undertake early replacement of access cavity with permanent restoration.

Materials for retrograde filling in root canal therapy.

Root canal therapy is a sequence of treatments involving root canal cleaning, shaping, decontamination, and obturation. It is conventionally performed through a hole drilled into the crown of the affected tooth, namely orthograde root canal therapy. When it fails, retrograde filling, which seals the root canal from the root apex, is a good alternative. Many materials are used for retrograde filling. Since none meets all the criteria an ideal material should possess, selecting the most efficacious material is of utmost importance. This is an update of a Cochrane Review first published in 2016. To determine the effects of different materials used for retrograde filling in children and adults for whom retrograde filling is necessary in order to save the tooth. An Information Specialist searched five bibliographic databases up to 21 April 2021 and used additional search methods to identify published, unpublished, and ongoing studies. We also searched four databases in the Chinese language. We selected randomised controlled trials (RCTs) that compared different retrograde filling materials, with the reported success rate that was assessed by clinical or radiological methods for which the follow-up period was at least 12 months. Records were screened in duplicate by independent screeners. Two review authors extracted data independently and in duplicate. Original trial authors were contacted for any missing information. Two review authors independently assessed the risk of bias of the included studies. We followed Cochrane's statistical guidelines and assessed the certainty of the evidence using GRADE. We included eight studies, all at high risk of bias, involving 1399 participants with 1471 teeth, published between 1995 and 2019, and six comparisons of retrograde filling materials. - Mineral trioxide aggregate (MTA) versus intermediate restorative material (IRM): there may be little to no effect of MTA compared to IRM on success rate at one year, but the evidence is very uncertain (risk ratio (RR) 1.09, 95% confidence interval (CI) 0.97 to 1.22; I2 = 0%; 2 studies; 222 teeth; very low-certainty evidence). - MTA versus super ethoxybenzoic acid (Super-EBA): there may be little to no effect of MTA compared to Super-EBA on success rate at one year, but the evidence is very uncertain (RR 1.03, 95% CI 0.96 to 1.10; 1 study; 192 teeth; very low-certainty evidence). - Super-EBA versus IRM: the evidence is very uncertain about the effect of Super-EBA compared with IRM on success rate at 1 year, with results indicating Super-EBA may reduce or have no effect on success rate (RR 0.90, 95% CI 0.80 to 1.01; 1 study; 194 teeth; very low-certainty evidence). - Dentine-bonded resin composite versus glass ionomer cement: compared to glass ionomer cement, dentine-bonded resin composite may increase the success rate of the treatment at 1 year, but the evidence is very uncertain (RR 2.39, 95% CI 1.60 to 3.59; 1 study; 122 teeth; very low-certainty evidence). Same result was obtained when considering the root as unit of analysis at one year (RR 1.59, 95% CI 1.20 to 2.09; 1 study; 127 roots; very low-certainty evidence). - Glass ionomer cement versus amalgam: the evidence is very uncertain about the effect of glass ionomer cement compared with amalgam on success rate at one year, with results indicating glass ionomer cement may reduce or have no effect on success rate (RR 0.98, 95% CI 0.86 to 1.12; 1 study; 105 teeth; very low-certainty evidence). - MTA versus root repair material (RRM): there may be little to no effect of MTA compared to RRM on success rate at one year, but the evidence is very uncertain (RR 1.00, 95% CI 0.94 to 1.07; I2 = 0%; 2 studies; 278 teeth; very low-certainty evidence). Adverse events were not assessed by any of the included studies. Based on the present limited evidence, there is insufficient evidence to draw any conclusion as to the benefits of any one material over another for retrograde filling in root canal therapy. We conclude that more high-quality RCTs are required.

Management of non-vital maxillary central incisor with intrinsic discoloration using walking bleach technique

Non-vital bleaching is a non-invasive technique for the treatment of intrinsic discoloration of teeth. Hydrogen peroxide and sodium perborate are commonly used bleaching agents. The aim of this case report is to demonstrate the non-vital bleaching technique in maxillary anterior teeth. Maxillary central incisors were isolated and root canal treatment was performed. Barrier space preparation was done using a heated instrument. Glass ionomer cement was used a barrier material. Mixture of hydrogen peroxide was placed in the canal and sealed with intermediate restorative material. After 1 week, the procedure was repeated to achieve the desired results. Non-vital bleaching is a minimally invasive procedure to restore the esthetics of a discoloured non-vital tooth. However, care should be taken to prevent any post-operative complications.

Assessment of bacterial and dye penetration through post/crown interim restorations while under simulated masticatory load.

The aim was to compare two temporary cements to determine which resisted bacterial and dye penetration under temporary posts/cores/crowns subjected to simulated masticatory function. Forty-six single canal human tooth roots were prepared for posts/crowns. A cotton pellet and Cavit were placed in each post space. Temporary posts/cores/crowns were cemented with Intermediate Restorative Material (IRM) (n = 23) or Tempocem (n = 23). Specimens were sterilised, then immersed in a mixture of Streptococcus gordonii and India ink, and subjected to 4 weeks simulated mastication. Dye penetration was assessed by visually inspecting the cotton pellets. Bacterial penetration was determined by placing the pellets into sterile broth and by plating them onto agar plates to confirm S. gordonii growth. There was no statistically significant difference between the cements and the dependent variables of bacterial and dye penetration. Hence, both cements are good options to cement temporary posts/cores/crowns during endodontic treatment of anterior teeth.

Effect of Injectable-Platelet Rich Fibrin on marginal adaptation of Bioactive Materials Used as Direct Pulp Capping; An Experimental Animal Study

ABSTRACTIntroduction: Vital pulp therapy has been known as one of the treatment optionsto preserve pulp vitality after being exposed by trauma or caries. Aim: This experimentexplored the effect of injectable-Platelet Rich Fibrin on marginal adaptation of two pulp capping agents (Mineral Trioxide Aggregate and Bioactive Bone Graft). Materials andmethods: A total of 64 teeth were used out of 8 healthy male beagle dogs. The teethwere randomly assigned into four groups, they were exposed and capped with differentcapping agents. Group A; capped with Mineral Trioxide Aggregate (MTA), Group B;capped with MTA+ i-PRF, Group C; capped with Bioactive Bone Graft (BBG), Group D; capped with BBG+i-PRF. Finally the access cavity was restored with IntermediateRestorative Material (IRM). At each predetermined interval, the dogs were sacrificed(1 month, and 3 months). The samples were then prepared for electron microscopicscanning evaluation. To compare between the gap percentage of four groups at eachinterval, Kruskal-wallis test; was used. Mann-Whitney U test; was used to pair-wisecomparison when Kruskal-wallis test is significant. Bonferroni’s correction was utilizedfor the pair-wise comparisons. Statistical significance was considered at P area between the capping materials and dentin, followed by group C (BBG), with theleast value recorded in group A (MTA). Conclusion: the findings from the current studysuggested that i-PRF provided a better marginal adaptation of either MTA or BBG tothe pulp and dentin, which improved with time from one month to three months.

Direct pulp capping using Simvastatin and MTA in dogs’ teeth: marginal adaptation SEM study

Aim: To investigate the marginal adaptation of Simvastatin (Smv), Mineral Trioxide Aggregate (MTA), and the combination of the two materials after direct pulp capping (DPC) in dogs’ teeth after three months. Methodology: DPC was performed at random on 18 maxillary and mandibular incisors of two dogs. The pulpal exposures in class V cavities were capped with either Smv or Smv+MTA or MTA. All cavities were restored with Intermediate Restorative Material (IRM). After a 90-day follow-up period, the dogs were euthanised and the incisors were sectioned into two halves and studied under the scanning electron microscope (SEM). The interface between the DPC materials and pulp as well as dentine is examined for gap mean percentage to the total area of the DPC material. Results: There was a statistically significant difference between Smv and Smv+MTA groups (P 0.05). The highest mean gap area percentage value was recorded in the Smv+MTA group (3.750±1.802) followed by the MTA group (2.121±1.166) while the lowest gap percentage was recorded in the Smv group (1.339±1.271). Conclusions: Simvastatin showed a good marginal adaptation property that encourages its use as DPC material.