Irrigant dynamics of a back-to-back double side-vented needle in root canals with various tapers: a computational fluid dynamics study.

Understanding the apical pressure and irrigant flow patterns in root canals is crucial for safe and effective irrigation. Therefore, this study aimed to assess the flow characteristics of irrigants in root canal models with varying tapers during final irrigation by employing various needle designs, including a back-to-back double-side-vented needle, through computational fluid dynamics. The root canal model was configured as a closed geometrical cone with a simulated apical zone (size 30) and features tapers of 4%, 6%, and 8%. Three needle types-open-ended needle (OEN), single side-vented needle (SSVN), and double side-vented needle (DSVN)-were investigated. The results indicated that for the 4% taper models, the open-ended needle generated the maximum apical pressure, followed by the double side-vented needle and the single side-vented needle. However, in the 6% and 8% tapering root canal models, the double-side-vented needle applied the lowest maximum apical pressure. Consequently, the DSVN can pose a risk for irrigant extrusion in minimally prepared canals due to heightened apical pressure. In wider canals, the DSVN exhibited lower apical pressure. The maximum irrigant replacement was observed with OEN compared to that of the closed-ended group for both flow rates. Additionally, compared with OENs, closed-ended needles exhibited nonuniform and lower shear wall stress.

Concept of Minimally Invasive Indirect Veneers.

Minimally invasive indirect veneers (MIIV) are ultrathin porcelain veneers that can be cemented onto labial surfaces after no or minimal tooth preparation. The benefits of no or minimal veneer preparation are conservation of tooth structure, absence of postoperative sensitivity, bonding to enamel, minimal flexural stresses, no need for provisionals and improved patient acceptance. However, no or minimal preparation veneers should be considered only after thorough functional and aesthetic evaluation. The article presented here illustrates a case of diastema closure using MIIV, to highlight the importance of treatment planning for achieving good results.

Medication-related tooth discoloration: a review.

Tooth discoloration is a common problem for which patients seek dental care. Various medications can directly or indirectly result in tooth discoloration. As clinicians, it is our responsibility to know these therapeutic drugs which can cause tooth discoloration and educate our fellow colleagues to take necessary precautions when prescribing these medications. Therefore, the objective of this paper is to give an overview of the various medications that can be linked to tooth discoloration and to suggest the precautionary measures that can be taken to avoid or minimize it. Clinical Relevance: Dental discoloration potential of medications always needs to be considered before prescribing them.

Sodium Hypochlorite Concentration and Postendodontic Pain - Unveiling the Optimal Balance: A Systematic Review and Meta-Analysis.

INTRODUCTION: This study systematically reviewed literature regarding the effect of different concentrations of sodium hypochlorite (NaOCl) used during root canal treatment (RCT) on postendodontic pain (PEP) and rescue analgesia. METHODS: Following registration with PROSPERO (CRD42023388916), a search was conducted using PubMed, Scopus, Web of Science, and Embase databases. Randomized controlled trials of patients receiving RCT which assessed PEP at different time intervals were included. Following data extraction and Cochrane risk of bias assessment 2, meta-analyses were performed to evaluate PEP during the first 48 hours along with rescue analgesic intake. The certainty of the evidence was evaluated using the Grading of Recommendations, Assessment, Development, and Evaluation approach. RESULTS: Five randomized controlled trials with 674 patients were included. One study exhibited a low risk of bias, while 4 raised some concerns. Patients treated with low concentrations of NaOCl (≤3%) were significantly less likely to report PEP at 24 hours (OR = 2.32; [95% CI, 1.63-3.31]; P < .05) and 48 hours (OR = 2.49; [95% CI, 1.73-3.59]; P < .05) as compared with high concentrations of NaOCl (≥5%). Furthermore, with low concentrations of NaOCl, significantly lesser moderate-severe PEP was reported at 24 hours (OR = 2.32; [95% CI, 1.47-3.62]; P < .05) and 48 hours (OR = 2.35; [95% CI, 1.32-4.16]; P < .05) and lesser analgesia was needed (OR = 2.43; [95% CI, 1.48-4.00]; P < .05). CONCLUSIONS: While PEP can be influenced by several factors, low certainty evidence suggests that when NaOCl is used as an irrigant during RCT, PEP may be less likely with lower concentrations of NaOCl. Moderate certainty evidence indicates that lesser analgesia may be required with lower concentrations of NaOCl. These results should be cautiously interpreted.

Effect of Dentine Conditioning with Silver Diamine Fluoride on Wettability of Root Canal Sealers.

OBJECTIVE: To test the null hypothesis that dentine treatment with silver diamine fluoride (SDF), a potent antimicrobial agent, following use of proteolytic and chelating agents does not influence the wettability of an epoxy resin (AH Plus, Dentsply Sirona, Charlotte, NC, USA) and a tricalcium silicate sealer (BioRoot RCS, Septodont, Saint-Maur-des-Fossés, France). METHODS: Seventy-two intraradicular dentine specimens were divided into six groups based on the final irrigation solutions used: 2.5% sodium hypochlorite (NaOCl) and 17% ethylenediaminetetraacetic acid (EDTA) (NaOCl-EDTA) (group 1); NaOCl-EDTA-NaOCl (group 2); NaOCl-EDTA followed by 3.8% SDF, NaOCl-EDTA-SDF (group 3); NaOCl-EDTA-NaOCl-SDF (group 4); SDF (group 5) and saline (group 6). After irrigation, the specimens were divided into subgroups according to the sealer used, AH Plus or BioRoot RCS. Contact angles were measured using a contact angle analyser. The data were analysed using an independent t test, one-way analysis of variance (ANOVA) and Tamhane T2 post hoc test, with the level of significance set at P < 0.05. RESULTS: In the epoxy resin sealer group, dentine surfaces treated with only SDF showed the lowest contact angle. This was significantly less than the groups in which NaOCl was used as the final irrigant (P < 0.05). In the tricalcium silicate-based sealer group, the groups treated with SDF showed significantly greater contact angles when compared to the control group (P < 0.05). CONCLUSION: It was concluded that SDF conditioning of dentine favours the wettability of epoxy resin sealer but is detrimental to the wettability of tricalcium silicate sealer.

Translucency characteristics of permanent maxillary central incisor in Indian population: An analytical cross-sectional study.

Background: Understanding the optical characteristics, especially the translucency patterns (TPs) in teeth can assist clinicians in creating biomimetic restorations. Aim: This study assessed the differences in enamel TPs and the area of translucency (AOT) in the most dominant teeth of an individual's smile according to their age and gender. Materials and Methods: This cross-sectional study was conducted on 140 consented individuals. Based on the age, there were four groups with 35 subjects in each. The digital imaging method is used to classify and differentiate different TPs. The AOT was measured with the assistance of ImageJ 1.51j8 software. Statistical Analysis Used: One-way ANOVA with a post hoc test was used to test the statistical significance difference among the various age groups, and an independent t-test was used to test the variations between genders. Results: The outcome of this study showed that the AOT was the highest for the 50 and above age group as compared to other age groups (P = 0.003). Although there were variations in the TPs between the two genders, the AOT showed no significant difference. Conclusion: The area of incisal third translucency in the upper central incisors varied between different age groups. However, gender had no influence in the area of incisal translucency. Wide variations in the TPs were seen based on age and gender.

Pulp hyperthermia during tooth preparation: the effect of rotary--instruments, lasers, ultrasonic devices, and airborne particle abrasion.

The rise in pulp temperature during restorative therapy can compromise vitality of the dental pulp. Of the various reasons for the increase in intrapulpal temperature, tooth preparation is considered to be the primary cause. This article describes the reasons for the rise in pulp temperature during various modalities of tooth preparation. The article also comments on the measures that need to be taken to avoid the risk of pulp hyperthermia during tooth preparation.

Nonsurgical gingival displacement in restorative dentistry.

Gingival displacement is critical for obtaining accurate impressions for the fabrication of fixed restorations, especially when the finish line is at or just within the gingival sulcus. Displacement of the gingival tissue is also important when dealing with the restoration of cervical lesions due to their proximity to the periodontal tissue. The methods of gingival tissue displacement can be broadly classified as nonsurgical and surgical techniques, with nonsurgical being the more commonly practiced method. Dentists must alter their armamentarium and gingival displacement techniques to meet specific demands and obtain predictable results. Hence, the purpose of this article is to describe the different means by which nonsurgical gingival displacement can be achieved effectively under a variety of clinical situations.

Effect of blood contamination and various hemostatic procedures on the push-out bond strength of Biodentine when used for furcation perforation repair.

BACKGROUND: Perforations in the furcation area are common procedural accidents that can impact the outcome of treatment. There are many bioactive materials available to repair these defects. AIM: The purpose of this study was to determine and compare the effect of 25% aluminum chloride solution, 20% ferric sulfate solution, and a 980-nm diode laser, when used for hemostasis, on the dislocation resistance of Biodentine placed to repair furcation perforation. MATERIALS AND METHODS: This in vitro study was conducted on fifty extracted human permanent mandibular molars, with ten teeth in each group. The stimulated perforations were contaminated with blood, except for one group. The contaminated groups were either treated with aluminum chloride, ferric sulfate, diode laser, or none at all. All the perforations were restored with Biodentine and tested for push-out bond strength. STATISTICAL ANALYSIS USED: One-way analysis of variance and Tukey's HSD post hoc test were applied with a level of significance set at 0.05. RESULTS: The dislocation resistance of Biodentine was found to be highest when aluminum chloride or diode laser was used for arresting bleeding. In contrast, the ferric sulfate group gave the lowest value for push-out bond strength (P < 0.05). CONCLUSIONS: According to the present study, the use of ferric sulfate as a hemostatic agent showed a negative effect on the bond strength of the calcium silicate cement to dentin. Furthermore, Biodentine performed better when diode laser and aluminum chloride were used for hemostasis.

Evaluation of indirect pulp capping using pozzolan-based cement (ENDOCEM-Zr®) and mineral trioxide aggregate - A randomized controlled trial.

BACKGROUND: Pulp capping should always be considered as the primary treatment of choice for teeth without irreversible pulpitis in lesions approaching dental pulp. The predictability of vital pulp therapy has improved with the introduction of newer bioceramic materials. AIM: The purpose of this randomized controlled trial was to compare the outcomes of mineral trioxide aggregate (MTA) (Angelus, Londrina, Brazil) and a pozzolan-based cement (ENDOCEM-Zr® [Maruchi, Wonju, Korea]) as an indirect pulp capping (IPC) material. MATERIALS AND METHODS: IPC was performed in forty patients who were randomly divided into ENDOCEM-Zr® and MTA groups. The outcome was assessed using clinical and radiographic tests at different time intervals. The prognostic factors on the outcome of IPC were also evaluated. RESULTS AND CONCLUSIONS: The success rate of ENDOCEM-Zr® and MTA groups was 94.7% and 89.4%, respectively. The results were not statistically significant. Binary logical regression showed that the age of the patient and the status of the pulp before treatment were deciding variables for the outcome of the study. Therefore, it was concluded from the study that the evaluated pozzolan-based cement could be used as an alternative to MTA because of its faster setting time and lower discoloration potential. In addition, pulp capping should be performed with caution in individuals above 40 years and in teeth with reversible pulpitis.

Effect of silver diamine fluoride-potassium iodide and 2% chlorhexidine gluconate cavity cleansers on the bond strength and microleakage of resin-modified glass ionomer cement.

BACKGROUND: Disinfection of the prepared cavity can be a crucial step in the longevity of restorations. The objective of this study was to compare the antimicrobial action (AMA) of silver diamine fluoride-potassium iodide combination (SDF-KI) with 2% chlorhexidine gluconate (CHX) and to compare the alteration in bond strength and microleakage while using SDF-KI and CHX as cavity cleansers in resin-modified glass ionomer cement (RMGIC) restorations. MATERIALS AND METHODS: Samples were grouped as follows: Group 1: Polyacrylic acid (PAA), Group 2: CHX, Group 3: SDF-KI, and Group 4: Distilled water (CTRL). AMA was assessed by measuring the zone of inhibition of the above-mentioned materials by dispensing them into the punch hole prepared on agar plates with an inoculum of Streptococcus mutans. For assessing the effect of the cavity cleansers on the bond strength of RMGIC, they were applied to the dentinal samples prepared from freshly extracted noncarious molars. After the surface was treated, cylindrical restoration of RMGIC was placed and allowed to set. The shear bond strength was then evaluated using a universal testing machine. Rhodamine-B dye penetration was viewed under a fluorescent microscope to evaluate the microleakage of RMGIC following surface treatment of the standardized cavities prepared on the cervical third of freshly extracted noncarious premolars. RESULTS: SDF-KI (34 ± 0.8 mm) showed potent AMA followed by CHX (23.9 ± 0.7 mm) and PAA (12.7 ± 0.8 mm). SDF-KI showed a drastic increase in the bond strength when compared to the PAA, CHX, and CTRL groups. Although the application of SDF-KI showed the least microleakage among all the groups, it was not statistically significant. CONCLUSION: The application of SDF-KI and CHX is useful against S. mutans in an in vitro study. Although SDF-KI group showed the least microleakage among the groups, it was not statistically significant. SDF-KI application has shown a drastic increase in the bond strength of RMGIC although further research is required for the suitable reasoning of the phenomenon.

Effect of various dentin disinfection protocols on the bond strength of resin modified glass ionomer restorative material.

BACKGROUND: Disinfection of dentin surface prior to any restorative therapy is important for the longevity of the treatment rendered. However, these dentin disinfection methods should itself not interfere with the adhesion of the restorative material. Therefore the aim of this study was to determine the effect of various dentin disinfection protocols on the shear bond strength (SBS) of resin modified glass ionomer cement (RMGIC). MATERIAL AND METHODS: The occlusal surface of 40 extracted premolars were trimmed to obtain a flat dentinal surface and was randomly divided into four groups. CTRL was the control group; NaOCl was 1% sodium hypochlorite disinfection group; CHX was 2% chlorhexidine disinfection group; and PAD was the photo-activated disinfection group. Then a predetermined dimension of RMGIC was bonded to the pre-treated dentin surfaces. Following this, each sample was tested for SBS using universal testing machine at a crosshead speed of 0.5mm/min. RESULTS: Among the test groups, CHX showed the least reduction in SBS and NaOCl the highest reduction in SBS as compared to the control group. PAD on the other hand showed significantly lower SBS than CTRL and CHX groups, but the values were higher than the NaOCl group. CONCLUSIONS: Thus, it could be concluded from the present study that use of chlorhexidine based dentin disinfection does interfere with the adhesion of RMGIC. However, photo-activated disinfection should be done with caution. Moreover, sodium hypochlorite based disinfectants should be avoided prior to the use of RMGIC. Key words:Chlorhexidine, Dentin disinfection, Photo-activated disinfection, Resin modified glass ionomer cement, Shear bond strength, Sodium hypochlorite.

Resurrecting an unsalvageable lower incisor with a mono-block approach.

Contemporary techniques, as well as the availability of bioactive and adhesive materials in endodontics, have helped revivifying teeth that were deemed hopeless. These newer materials and techniques would enable the clinician: (a) to predictably stop microbial activity (b) to achieve a total corono-apical fluid tight seal and (c) to strengthen mutilated teeth by obtaining intra-radicular reinforcement through mono-block effect. This case report demonstrates the successful treatment of a mutilated anterior tooth with the use of bioactive and adhesive materials to obtain a total seal and mono-block effect. This article also shows the use of a simple method in the placement of root filling cement into the root canal.

Medication-related dental erosion: a review.

Dental erosion has become a major problem that affects the long-term health of the dentition. Among the various potential causes for erosive tooth wear, the different drugs prescribed for patients may be overlooked. Several therapeutic medications can directly or indirectly be associated with dental erosion. It is the responsibility of oral health providers to make both patients and colleagues aware of drugs that may contribute to this condition. Therefore, the purpose of this discussion is to provide an overview of the various therapeutic medications that can be related to tooth erosion. The authors also include precautionary measures-summarized as The 9 Rs-to avoid or at least reduce medication-induced erosion.

Haemostatic agents on the shear bond strength of self-adhesive resin.

BACKGROUND: Dentin surface contaminated with haemostatic agents can interfere with the bonding of self-adhesive resin cement. Therefore the purpose of this study was to evaluate the effect of various haemostatic agents such as Aluminium chloride, Ferric sulphate and Tannic acid on the shear bond strength of self-adhesive resin luting agent. MATERIAL AND METHODS: The buccal surfaces of extracted premolars were flattened to expose the dentine. The teeth were then randomly divided into four groups. In Group I Aluminium Chloride was applied on the flattened dentinal surface, in Group II Ferric Sulphate was applied to exposed dentin surface, in Group III tannic acid was applied on to the dentinal surface, and the control group, i.e. Group IV was rinsed with saline. After the surface treatment, all the teeth were air dried. Then a predetermined dimension of RelyX™ U200 self-adhesive resin cement was bonded to the pretreated dentin surfaces. The samples were then stored under 370C in distilled water for 24 hours under 100 % humidity. Following this each sample was tested for shear bond strength with an Instron testing machine at a crosshead speed of 1mm/min. RESULTS: There was significant difference in the shear bond strength of control and tannic acid contaminated group (p<0.05), whereas there was no significant differences between the shear bond strength between control and aluminium chloride and ferric sulphate groups (p>0.05). CONCLUSIONS: The usage of haemostatic agent can negatively affect the bond strength of self-adhesive resin cement (Rely X) on to the dentin surface. As per the study Tannic acid significantly weakened the bond between the self-adhesive resin and dentin. Key words:Aluminium chloride, Ferric sulphate, haemostatic agent, self-adhesive resin cement, shear bond strength, Tannic acid.

Effect of calcium hydroxide and triple antibiotic paste as intracanal medicaments on the incidence of inter-appointment flare-up in diabetic patients: An in vivo study.

AIM: To evaluate and compare the effect of antibacterial intracanal medicaments on inter-appointment flare-up in diabetic patients. MATERIALS AND METHODS: Fifty diabetic patients requiring root canal treatment were assigned into groups I, II, and III. In group I, no intracanal medicament was placed. In groups II and III, calcium hydroxide and triple antibiotic pastes were placed as intracanal medicaments, respectively. Patients were instructed to record their pain on days 1, 2, 3, 7, and 14. Inter-appointment flare-up was evaluated using verbal rating scale (VRS). RESULTS: Overall incidence of inter-appointment flare-up among diabetic patients was found to be 16%. In group I, 50% of the patients and in group II, 15% of the patients developed inter-appointment flare-up. However, no patients in group III developed inter-appointment flare-up. The comparison of these results was found to be statistically significant (P = 0.002; χ(2) = 12.426). However, with respect to intergroup comparison, only the difference between groups I and III was found to be statistically significant (P = 0.002; χ(2) = 12.00). CONCLUSIONS: Calcium hydroxide and triple antibiotic paste are effective for managing inter-appointment flare-ups in diabetic patients. Triple antibiotic paste is more effective than calcium hydroxide in preventing the occurrence of flare-up in diabetic patients.

Evaluation and comparison of bond strength to 10% carbamide peroxide bleached enamel following the application of 10% and 25% sodium ascorbate and alpha-tocopherol solutions: An in vitro study.

AIM: To evaluate and compare composite bond strength to carbamide peroxide bleached enamel following the application of 10% and 25% sodium ascorbate and alpha-tocopherol solutions. MATERIALS AND METHODS: Sixty premolars were divided into six groups. Groups I and VI served as unbleached and bleached controls respectively. Groups II, III, IV and V served as the experimental groups and were subjected to 10% carbamide peroxide bleaching followed by 10 min application of 10% and 25% sodium ascorbate and 10% and 25% alpha-tocopherol solutions, respectively. Following composite bonding, shear bond strength was determined and the results were analyzed using ANOVA and Tukey highest significant difference test. RESULTS: Only Group IV showed significantly lower bond strength when compared to Group I (unbleached control). When compared to Group VI (bleached control), except Group IV, groups II, III and V showed significantly higher bond strength. However, there was no statistically significant difference between the experimental groups corresponding to 10% and 25% and similar concentrations of sodium ascorbate and alpha-tocopherol solutions. CONCLUSION: Following 10% carbamide peroxide bleaching, except 10% alpha tocopherol, 10 min application of 10% and 25% sodium ascorbate and 25% alpha-tocopherol solutions significantly improves the shear bond strength of composite resin to enamel.

Management of supernumerary teeth.

Supernumerary paramolars are the rare anomalies of the maxillofacial complex. These are more common in the maxilla than in the mandible. This article reviews the etiology, frequency, classification, complications, diagnosis and management of supernumerary teeth (bilateral maxillary paramolars).

Effects of saliva contamination and decontamination procedures on shear bond strength of self-etch dentine bonding systems: An in vitro study.

OBJECTIVE: This study aims to evaluate the effect of saliva contamination on the shear bond strength of two self-etch dentine bonding systems and also investigate the effect of decontamination procedure on the recovery of bond strength. MATERIALS AND METHODS: Sixty premolars extracted for orthodontic reason were obtained and the buccal surfaces of teeth were reduced to create a flat dentine surface. The samples were randomly divided into three sub-groups for AdheSE (ASE) (Ivoclar - Vivadent, Schaan, Liechtenstein) and three sub-groups for Adper Prompt Self-Etch Adhesive (ADP) (3M ESPE, St Paul, MN, USA) of 10 each. For AdheSE (ASE); ASE-I was the control group (primer applied to fresh dentine surface), ASE-II was the contamination group (primer applied, followed by saliva contamination and then air dried) and ASE-III was the decontamination group (primer applied, followed by saliva contamination, air dried and then primer reapplied). For Adper Prompt (ADP); ADP-I was the control group (self-etch adhesive applied to fresh dentine surface), ADP-II was the contamination group (self-etch adhesive applied, followed by saliva contamination and then air dried) and ADP-III was the decontamination group (self-etch adhesive applied, followed by saliva contamination, air dried and then self-etch adhesive reapplied). Followed by the bonding procedure, a 5 mm composite resin block with Filtek P-60 (3M ESPE, St Paul, MN, USA) was built on the substrate. Shear bond strength (SBS) was tested with Instron Universal testing machine (Instron Corporation, Canton, MA, USA) with a cross head speed of 1 mm per minute. Data obtained was subjected to one way ANOVA test, while the inter group comparison was made using Tukey's multiple comparison and Unpaired t-test. RESULTS: In AdhSE group (ASE), the sub-group ASE-II (contamination group) [5.4 ± 2.2 MPa] showed lower SBS than ASE-I [11.8 ± 2.6 MPa] and ASE-III [8.9 ± 3.3 MPa], which was statistically significant. There was no significant difference in the bond strength between the ASE-I (control group) and ASE-III (decontamination group). In Adper Prompt group (ADP), there was a severe decrease of bond strength in ADP-II (contamination group) [4.6 ± 1.1 MPa] when compared to ADP-I (control group) [7.4 ± 1.4 MPa] and ADP-III (decontamination subgroup) [14.1 ± 2.2 MPa] which was statistically significant. The bond strength of ADP-III wherein Adper Prompt bonding agent was reapplied after salivary contamination was found to be statistically significant than ADP-I and ADP-II. CONCLUSION: Saliva contamination reduces the dentine bond strength of both the self-etch systems; AdheSE and Adper Prompt. Re-application of the primer for the AdheSE and re-application of the adhesive for the Adper Prompt after air drying the saliva off can recover the dentine bond strength. In the Adper Prompt group, the added application of adhesives to decontaminate saliva not only recovered the bond strength but also improved it significantly.