To review the analytical methods for carious and erosive demineralization an initial search of peer-reviewed scientific literature from the digital library database of PubMed/Medline indexed journals published up to early 2022 was carried out based on keywords relevant to the topic criteria including bibliographic citations from the papers to gather the most updated information. This current review aims to provide an updated overview of the advantages, limitations, and potential applications of direct and indirect research methods available for studying various dynamic stages of carious and erosive demineralization in enamel and dentin. This paper categorizes and describes the most suitable, frequently adopted and widely used quantitative and qualitative techniques in in vitro/in vivo research which are well-established, emerging, or comparatively novel techniques that are being explored for their potential validation.

Background: Conflicting findings on the potency of antibiotic pastes versus calcium hydroxide (CH) have been evident in the literature. Aims: To compare the antibacterial efficacy of single antibiotic paste (SAP), double antibiotic paste (DAP), triple antibiotic paste (TAP), and modified TAP (mTAP) with CH on bacterial biofilms. Methods: PubMed, Scopus, and Embase were comprehensively searched until August 23, 2021. The study protocol was registered in the PROSPERO. Ex vivo studies performed on Enterococcus faecalis or polymicrobial biofilms incubated on human/bovine dentin were selected. The quality of the studies was assessed using a customized quality assessment tool. Standardized mean difference (SMD) with a 95% confidence interval (CI) was calculated for the meta-analysis. Meta-regression models were used to identify the sources of heterogeneity and to compare the efficacy of pastes. Results: The qualitative and quantitative synthesis included 40 and 23 papers, respectively, out of 1421 search results. TAP (SMD = −3.82; CI, −5.44 to −2.21; P < 0.001) and SAPs (SMD = −2.38; CI, −2.81 to − 1.94; P < 0.001) had significantly higher antibacterial efficacy compared to the CH on E. faecalis biofilm. However, no significant difference was found between the efficacy of DAP (SMD = −2.74; CI, −5.56–0.07; P = 0.06) or mTAP (SMD = −0.28; CI, −0.82–0.26; P = 0.31) and CH. Meta-regression model on E. faecalis showed that SAPs have similar efficacy compared to TAP and significantly better efficacy than DAP. On dual-species (SMD = 0.15; CI, −1.00–1.29; P = 0.80) or multi-species (SMD = 0.23; CI, −0.08–0.55; P = 0.15) biofilms, DAP and CH had similar efficacy. Conclusions: Ex vivo evidence showed that antibiotic pastes were either superior or equal to CH. The studied SAPs had considerably higher or similar antibacterial effectiveness compared to DAP, CH, and TAP. Hence, combined antibiotic therapy was not necessarily required for root canal disinfection ex vivo.

Radiation therapy, either used alone or in combination with surgery and or chemotherapy, is the most commonly utilized modality for treating head and neck cancers. Patients undergoing radiation therapy usually experience significant early and late-onset toxicities/adverse effects. Radiation-related caries (RRC) is a common complication that detrimentally affects patients' quality of life (QoL). A clearer understanding and more uniform approach to scoring systems help provide a more accurate diagnosis, form treatment protocols, plan, and evaluate outcomes of preventive initiatives and create scientific databases. Many indices have been used to assess and quantify the dental caries experience after radiotherapy. Considering the need for uniform standards for measuring radiation caries, indices specific to radiation caries have been proposed in the literature to capture postradiation damage to the dentition accurately. This narrative review aims to consolidate the evolution of different indices used for scoring RRC to improve the understanding of radiation caries assessment.

Background: There have been numerous cone-beam computed tomography (CBCT) studies done over the years to analyze the canal configurations among various racial and ethnic population groups. Several of these studies have highlighted a certain consistency in the incidence of particular features within these population subsets. Aim: The study aimed to analyze the root morphology and canal configurations of the maxillary first premolar (Mx1PM) in the Indian Dravidian subpopulation using CBCT. Setting and Design: This study involved a retrospective analysis of 200 CBCT scans, which included 400 Mx1PM. Methods: The CBCT images were evaluated, and the number of roots and canal configurations was recorded as per the Vertucci's classification. Statistical Analysis: Variations in the number of roots and canal anatomies were statistically interpreted using the Chi-square test of association with the significance level set at P < 0.05. Results: Among the 400 Mx1PM studied, 116 (29%) teeth displayed single roots and 284 (71%) showed the presence of two roots. The single-rooted premolars revealed a varied canal configuration with a predominance of Vertucci's Type II configuration in around 53.4% of the Mx1PM. The two-rooted premolars revealed 100% Type I canal configuration. Conclusion: The Mx1PM studied predominantly showed the two-rooted morphology with independent canals in each root. There was no significant difference between the teeth on either side of the same arch. The CBCT is an excellent nondestructive modality that can help us study the internal anatomy of pulp space accurately.

Background: The pursuit of esthetics and superior mechanical properties prompted the layering of Yttrium stabilized Zirconia with ceramic material. However, the bioinert nature of zirconia causes the chipping off of this ceramic layer. Selective infiltration etching (SIE) of zirconia provides good bond strength between zirconia and veneering ceramic. Materials and Methods: One hundred and fifty zirconia specimens of dimensions 5 × 5 × 10 mm were divided into 5 groups. Group 1: Air abrasion with 30 μ Al₂O₃ for 15 s with 0.4 bar pressure. Group 2: SIE and heat-induced maturation (HIM) as demonstrated by Abousheilb. Group 3: Sintered zirconia specimens were taken up for air abrasion followed by SIE/HIM. Group 4: Air abrasion and SIE performed on unsintered specimens followed by heat treatment at 1500°C. Group 5: Air abrasion performed on unsintered zirconia specimens followed by heat treatment at 1500°C followed by SIE/HIM. The samples were then layered with ceramic and subjected to shear bond strength (SBS) analysis. Results: The mean and standard deviation were calculated for the data. The mean SBS among the groups was compared using ANOVA. The post hoc Bonferroni test was applied to compare between the groups. The mean SBS was highest for Group 5 (47.89 ± 6.53) followed by Group 2 (34.94 ± 3.04), Group 3 (32.56 ± 6.04), Group 1 (29.12 ± 7.37), and Group 4 (27.56 ± 7.54). ANOVA test showed statistically significant differences among the groups (F = 48.86, P = 0.00). Conclusion: SIE/HIM when combined with sandblasting with appropriate heat treatment demonstrated a significant increase in bond strength. This prolongs the longevity of the restoration, thereby meeting the clinical needs.

Introduction: This study aimed to evaluate the shaping ability of TruNatomy (Dentsply Maillefer, Ballaigues, Switzerland), VDW.ROTATE (VDW GmbH, Munich, Germany) and ProTaper Gold (Dentsply Maillefer, Ballaigues, Switzerland) during the preparation of resin-printed mandibular molar mesial root canals. Materials and Methods: Thirty-three printed resin-based mandibular mesial roots with two canals were obtained from extract tooth cone-beam computed tomography (CBCT) image. The printed teeth were divided into three groups (n = 11) according to the system used for root canal preparation: TruNatomy, VDW.ROTATE, and ProTaper Gold. The specimens were scanned using CBCT imaging before and after root canal preparation. Then images were registered using a dedicated software and changes in the canal area, volume, untouched canal surface, and the maximum and minimum dentin wall wear were calculated. Statistical Analysis Used: Data were statistically analyzed using Shapiro–Wilk for normality, one-way ANOVA, and Tukey or Kruskal–Wallis H tests with alpha set at 5%. Results: No differences were observed for changes in the canal area, volume, untouched canal surface area, and minimum dentine wall wear parameters for the whole canal length (P > 0.05). The mean of untouched canal surface area for the TruNatomy, VDW.ROTATE, and ProTaper Gold was 40%, 44%, and 44%, respectively. The maximum dentine wall wear was significantly lower in the ProTaper Gold group than in the TruNatomy and VDW.ROTATE groups (P < 0.05). Conclusions: TruNatomy, VDW.ROTATE, and ProTaper Gold systems showed similar shaping ability in printed resin-based mandibular mesial roots without clinically significant errors. A large amount of untouched canal surface area was observed for all systems.

Aims: Evaluate and compare antibacterial efficacy of nisin, calcium hydroxide (Ca (OH)₂), and Triple antibiotic paste (TAP) mixed with distilled water and chitosan as an intracanal medicament on Enterococcus faecalis after 1^st and 7^th day. Settings and Design: Experimental in vitro study. Materials and Methods: One hundred and twenty Decoronated single-rooted premolars were prepared and autoclaved. Specimens were placed in brain heart infusion (BHI) broth of a 24 h old E. faecalis (ATCC 29212) suspension. The canal was infected for 21 days, followed by grouping as-Group 1: Nisin + distilled water; Group 2: Nisin + 2% chitosan; Group 3: Ca (OH)₂ + distilled water; Group 4: Ca (OH)₂ + 2% chitosan; Group 5: TAP + distilled water; Group 6: TAP + 2% chitosan and were incubated for 1 and 7 days. Dentin scrapings from 10 specimens at each time interval were transferred into BHI broth and incubated, Serially diluted and colony-forming unit (CFU) count was assessed after 1^st and 7^th day. Statistical Analysis Used: Kruskal–Wallis test to compare mean CFUs after day 1 and day 7. Mann–Whitney post hoc Analysis to estimate significance. Wilcoxon Signed-Rank Test to compare mean CFUs between day 1 and day 7. Results: After 1 day, Group 6 showed least CFUs than other groups and highest CFUs was with Group 3. There was no difference statistically when Group 5 and Group 2 were compared. After 7 days, Group 6 showed least CFUs than other groups with no significant difference between Group 1 and Group 5 as well as no significant difference between Group 2, Group 5 and Group 6. Conclusions: TAP with chitosan can be the medicament of choice for 1-day placement and was equivalent to nisin with chitosan combination after 7 days.

Context: Relation between the adequate intensity output of curing lights on color stability of composite resin is well accepted. Aims: To investigate the effect of different light-curing intensities and its relation to color stability of different polymerized composite resin materials using the spectophotometric analysis. Settings and Design: Comparative in vitro study done on composite resin discs. Subjects and Methods: A total of 180 discs comprising sixty discs prepared from three different composite resins, namely microhybrid composite resin (Filtek Z100,3M ESPE), nanohybrid composite resin (Filtek Z250 XT, 3M ESPE), and nanofilled composite resin (Filtek Z350 XT,3M ESPE) using three different light curing intensities, viz., 325–425 mW/cm², 750–850 mW/cm², and 1000–1100 mW/cm². Later these discs were stained with 2% methylene blue followed by re-absorption in absolute alcohol for supernatant solution preparation which is used for the spectrophotometric analysis. Statistical Analysis Used: Spectrophotometric absorption values were analyzed using the one-way ANOVA test for intergroup analysis. Results: Mean stain absorption was the highest with nanofilled composite resin (Filtek Z350 XT,3M ESPE) after exposure with light-curing intensity of 325–425 mW/cm² and least with microhybrid composite resin (Filtek Z100, 3M ESPE) after exposure with light-curing intensity of 750–850 mW/cm² and this difference found was highly significant statistically (P < 0.001). Conclusions: Microhybrid composite resin (Filtek Z100, 3M ESPE) cured with intensity of 750–850 mW/cm² showed least stain absorption indication most color stability and esthetic function.

Context: Vehicles combined with calcium hydroxide, as an intracanal medicament, play a key factor in affecting antibacterial, calcium release, and pH. Aims: The aim of this study is to investigate the effect of three vehicles (glycerin, chlorhexidine gluconate/CHX, and chitosan nanoparticle) combined with calcium hydroxide as an intracanal medicament on antibacterial efficacy against Enterococcus faecalis, calcium ion release, and pH of at different interval times of 7 and 14 days. Settings and Design: The research was experimental laboratory. Materials and Methods: Each study used 24 samples of eight teeth each and was randomly divided into three groups based on the vehicle of calcium hydroxide: group 1: glycerin, group 2: CHX, and group 3: chitosan nanoparticles. Each vehicle group was then further divided into two subgroups of four teeth based on the interval times (group A: 7 days and group B: 14 days). The antibacterial efficacy was determined using an agar diffusion method. Calcium ion release was analyzed with atomic absorption spectrometry, and pH was measured using a pH meter. Statistical Analysis Used: Data from each study were analyzed by two-way ANOVA, followed by Tukey's test with a significance level of 95%. Results: The results exhibited that chitosan nanoparticles had the highest antibacterial efficacy against E. faecalis, calcium ion release, and pH, while the lowest was glycerin at 7 and 14 days (P < 0.05). Conclusion: Calcium hydroxide combined with chitosan nanoparticle as an intracanal medicament produced the highest antibacterial efficacy against E. faecalis, calcium ion release, and pH than glycerin and CHX at intervals of 7 and 14 days.

Context: Although preservation of the tooth structure is quoted as the main advantage of sealing of carious lesions, there are no long-term studies comparing the maintenance of dental tissue after restoration or after caries sealing. Aim: To measure the radiographically visible loss of dental tissue after conventional restoration and sealing of carious lesions. Subjects and Methods: This study was a secondary analysis of two randomized controlled clinical trials, one conducted in Brazil and another in Belgium, which evaluated two different therapies for the treatment of occlusal carious lesions in permanent teeth: sealant (SE) without previous carious tissue removal or restoration (RE) with total removal of carious dentin. The greater depth and width of sealed carious lesions and restorations were compared. Statistical Analysis: The independent t-test was used to compare therapies at different time points, while the paired t-test was used to compare the same therapy over time. Results: Carious lesions in the RE and SE groups showed similar measurements at baseline (P > 0.05). Over time, significantly greater loss of tooth structure was observed in the RE group than in the SE group. No increase in lesion depth or width was observed in the SE group, suggesting no progression of sealed lesions. Conclusion: Sealing of carious lesions resulted in greater preservation of dental tissue.

Background: Pulp sensibility testing is an essential part of the diagnostic process in the assessment of pulpal health. Several lines of evidence suggest an interaction between control of blood pressure and pain regulatory mechanisms. Aim: The aim of the study is to compare pulp sensibility test responses in normotensive and hypertensive individuals. Materials and Methods: Ninety-eight patients participated in the study, with 49 individuals each in the hypertensive and normotensive groups. A minimum of 4 and maximum of 8 sound teeth were included in the study each from the anterior, premolar, and molar, i.e., 4 teeth from either arch. A total of 832 teeth were tested. The value and time when the responses evoked for electric pulp test (EPT) and cold test were recorded respectively. Statistical Analysis: For intergroup and intragroup analyses, independent t-test and paired t-test were utilized. Results: A statistically significant difference was noted in values for EPT as well as cold test responses when both the groups were compared (P < 0.01). Higher values were obtained with the hypertensive group. Conclusion: Patients with established hypertension showed an increased threshold to electric pulp testing and cold stimulus as compared to normal healthy individuals.

Aim: The aim of this study was to evaluate the prevalence and anatomical configuration of the C-shaped canal in permanent maxillary and mandibular second molars in the Greater Noida population by compiling the results of data that used cone-beam computed tomography (CBCT) analysis. Subjects and Methods: CBCT images were taken from the archive in the department of oral medicine and radiology taken for diagnostic purposes referred by other departments in the dental college. Five hundred CBCT records of patients, between the age group of 15–40 years, containing maxillary second molars and mandibular second molars were selected and reviewed. Statistical Analysis: Statistical analysis was done using the Chi-square test to find out the most common configuration of the C-shaped canal between maxillary and mandibular second molars. Results: Hundred and ten out of 500 patients had C-shaped canals (22%). Among them, 58 teeth (52.7%) were continuous C-shaped canals, 41 teeth (37.3%) were semicolon-shaped canals and 11 teeth (10%) had separated canals. (Chi-square test value = 8.26, P = 0.024). Statistically significant difference was found in configuration types. Among the jaw type, 62 maxillary second molar presented with C-shaped canal (25.1%) and 48 mandibular second molar presented with C-shaped canal (18.9%) (Chi-square test value = 3.87, P = 0.276). However, the difference was statistically insignificant in relation to the jaw type. Conclusions: Within the limitation of the study, we can conclude that the overall prevalence of C-shaped canals was 22% and the most common C-shaped canal configuration type was continuous (52.7%). However, no statistically significant difference was found in relation to jaw type.

Aim: To compare the effectiveness of different intracanal medicaments against polymicrobial biofilm formed by Enterococcus faecalis, Staphylococcus aureus, and Candida albicans. Materials and Methods: Eighty mature human roots with intraradicular polymicrobial biofilm were randomly assigned into four groups (n = 20). Intracanal medicaments 0.2% polyhexamethylene biguanide (PHMB), 2% chlorhexidine (CHX), and calcium hydroxide (CH) were applied into the root canals. Collected dentine samples were tested at 7^th, 15^th, and 30^th day for microbial growth, and the colony-forming units per ml (CFU/ml) were determined. Results: The CFU/ml data were analyzed using unpaired t-test and one-way ANOVA-F comparison test. All medicaments resulted in a significant reduction (P < 0.05) in microbial growth at all time intervals compared to the control group. CHX and PHMB showed a similar reduction in CFU/ml at 7^th and 15^th day but significantly more than CH at all time intervals. At 30^th day, PHMB caused a significantly more reduction in CFU/ml than CHX. Conclusions: All the three tested intracanal medicaments such as CH, CHX, and PHMB Gel were effective in reducing the microbial count. CH has a limited antimicrobial effect against the polymicrobial biofilm found inside the root canal. 2% CHX gel has a time-dependent antimicrobial effect. PHMB has a superior antimicrobial effect in comparison with CHX and CH.

Background: The ultimate goal of endodontic therapy is to eliminate all microorganisms present inside root canal and thereby sealing all the possible communicating pathways between pulpal and periradicular tissues, which prevents all the factors that cause recontamination and reinfection of the root canal system. If endodontic treatment fails, next approach is surgical endodontics. Bioceramics are recently introduced materials specifically designed for their potential use in medical field and dentistry. Aim: To evaluate and compare the push-out bond strength of mineral trioxide aggregate (MTA) by adding titanium dioxide (TiO2), silver, and silicon dioxide nanoparticles. Materials and Methods: Totally, 60 single-rooted human teeth were used. Middle third of the root was sectioned to obtain 2-mm thick root section. Acrylic was adapted to the section to obtain disks of 5 mm diameter and 2 mm thickness. Canal was prepared by GG Drill. Samples were divided into four groups of 15 each (n = 15): • Group I (control): MTA • Group II: MTA + TiO₂ nanoparticles. • Group III: MTA + silver nanoparticles. • Group IV: MTA + silicon dioxide nanoparticles. The cement mixture was compacted into the canal. Samples were subjected to push-out bond strength using universal testing machine. Statistical Analysis Used: The data were analyzed statistically by analysis of variance and post hoc comparison by Tukey's t-test. Results: The highest push-out bond strength was shown by Group II (MTA with TiO2 nanoparticles), followed by Group III (MTA with silver nanoparticles) and Group I (MTA control group). The lowest push-out bond strength was shown by Group III (MTA with silicon dioxide nanoparticles). Conclusions: TiO₂ and silver nanoparticles when added into MTA lead to an increase in push-out bond strength of MTA.

Background: Guided conservative endodontic access is a novel technique and the influence of such access cavities on apical debris extrusion (ADE) can have a significant effect on postoperative pain. Objective: This study compared ADE and preparation time (PT) in the mesial canals of the mandibular first permanent molars in different access cavity designs and the amount of sodium hypochlorite in the extruded debris using attenuated total reflection-Fourier transform infrared spectrometer (ATR-FTIR). Materials and Methods: Human mandibular first permanent molars (N = 72) were selected and randomly divided into six groups (n = 12) based on type of cavity design and files used: Group 1, Conservative Access Cavity [ConsAC])-WaveOne Gold; Group 2, ConsAC-Mtwo; Group 3, ConsAC-XP-endo shaper; Group 4, Traditional Access Cavity [TradAC])-WaveOne; Group 5, TradAC-Mtwo; and Group 6, TradAC-XP-endo shaper. All the ConsAC were prepared with a customized template fabricated using cone beam computed tomography. ADE evaluation was done using the Myers and Montgomery set up. All the instruments were used according to the manufacturers' instructions, followed by a final irrigation using Endoactivator. The time taken for preparation was calculated using a digital watch. Five samples in each group was taken and subjected to ATR-FTIR analysis. Results: There was no significant difference between the groups with respect to ADE (P > 0.05). Whereas, a statistically significant difference was seen in PT between the TradAC and ConsAC (P < 0.05). Using ATR-FTIR, it was found that all the samples of extruded debris had the presence of sodium hypochlorite. Conclusions: All instrumentation systems produced ADE irrespective of access cavity design. The time taken for preparation of canals in ConsAC was significantly longer compared to TradAC. Clinical Relevance: ADE can translate clinically as postoperative pain. Assessing the ADE in ConsAC could shed light on the type of file systems that can be used in such cavities in order to minimize postoperative pain clinically.

Context: Endodontically treated premolars are currently restored with direct bonded techniques in conservative manner enabling them to bear functional stresses homogeneously. Aim: The study aimed to evaluate the effect of placement of compactable glass fibers in reinforcing the endodontically treated teeth in a novel conservative manner. Settings and Design: Research laboratory, in vitro study. Materials and Methods: Seventy-five extracted maxillary premolars were procured. Fifteen teeth were left untreated (Group A) and the remaining teeth were endodontically treated followed by standardized mesio-occluso-distal preparation and randomly assigned to experimental groups (n = 15) as follows: (B) no restoration, (C) restoration with composite, (D) EverStick^® POST followed by composite, and (E) vertical glass fibers within 3 mm of the coronal root canal space and buccopalatal flaring of the coronal fibers followed by composite. After conditioning and thermocycling, specimens were loaded under a universal testing machine to evaluate fracture resistance and fracture pattern of specimens. Statistical Analysis Used: Obtained scores were statistically analyzed using one-way analysis of variance test for stress analysis, post hoc Tukey's test for intergroup comparison, and Chi-square test for analysis of favorable and unfavorable fracture. Results: The fracture resistance was highest to lowest as follows: Group A > E > C > D > B (P < 0.001). Conclusion: EverStick^®POST used in conservative manner improved fracture strength of teeth significantly.

Aim: The aim of this study was to evaluate and compare the regenerative endodontic potential of dexamethasone-coated bioglass nanofiber (Dex-BGnf), bioglass nanofiber (BGnf), and platelet-rich fibrin (PRF) for inducing regeneration in necrotic immature permanent teeth. Materials and Methods: A total of 36 (n = 12) immature necrotic teeth with or without evidence of periapical lesion were included in the study. Patients were randomly allocated into three groups, based on the scaffolds used: Group I (PRF), II (BGnf), and III (Dex-BGnf). The clinical (electric pulp test) and radiographic evaluations (percentage increase in apical diameter, root length, root dentin thickness, and periapical healing) were compared at 6 and 12 months after the procedure with baseline records. Statistical Analysis: One-way ANOVA, post hoc Tukey analysis, and Kruskal–Wallis test were used for evaluating the data. A 6- and 12-month improvement analysis was done using paired t-test and Friedman test. Results: Clinically, all the 36 teeth were asymptomatic, but none gave a positive response to Electric Pulp Test (EPT) in time interval of 12 months. Dex-BGnf showed a statistically significant improvement in terms of increase in root length (P = 0.020) and root dentinal thickness (P = 0.001) when compared to PRF after 12 months. Conclusion: The study has shown that Dex-BGnf yielded significantly better results than PRF for inducing apexogenesis in necrotic immature teeth.

This article reports nonsurgical endodontic management of bilateral maxillary first molars with an unusual morphology of a single root and a Sert and Bayirli type-IX canal configuration. A 41-year-old female reported with dull continuous pain in the maxillary left and right quadrants. On clinical examination, the maxillary first molars on both sides were carious with pulpal exposure and radiographic evaluation revealed an unusual anatomy of single root and single canal for both of them. Based on clinical and radiographic examination, tooth numbers 16 and 26 were diagnosed with symptomatic irreversible pulpitis and symptomatic apical periodontitis. Root canal treatment was initiated and cone-beam computed tomography (CBCT) imaging was advised on encountering unusual internal anatomy. The CBCT images revealed the presence single root and a Sert and Bayirli type-IX canal configuration bilaterally. Root canal treatment was performed under magnification using the dental operating microscope.

Double-curved canals, despite their rarity, pose a great challenge to complete endodontic treatment, and the difficulty lies in negotiating these canals and reaching their apex, whereas the greatest difficulty lies in their shaping, disinfection, and obturation. Conventional methods require excessive preflaring to the level of the first curvature to facilitate access and handling of the second one. Modern technologies facilitate dealing with these cases without compromising the dental tissues, metal alloys have become more flexible, and activation techniques have made it possible to deliver irrigants deeper. The triad of minimum shaping with tactile-controlled activation technique, hybrid irrigation, and sealing with bioceramics constitute an integrated and effective method to deal with these cases, and this protocol was used in the following three cases.