Fracture Resistance of Endodontically Treated Premolars Using Nanohybrid Composite, Fiber-Reinforced Composite, Horizontal Glass Fiber Posts, and Ceramic Inlays: An In Vitro Study.

INTRODUCTION: This study evaluated the resistance to fracture of endodontically treated premolars (ETPs) with mesio-occluso-distal (MOD) cavities filled with nanohybrid composite (NHC), fiber-reinforced composite (FRC), horizontal glass fiber posts (HFP), and ceramic inlays (CI). METHODS: Eighty-four intact maxillary premolars were taken, and endodontic treatment was performed followed by MOD cavity preparations (except in the control group). They were distributed into 7 groups based on type of restoration: intact teeth (control group), ETP + MOD (not restored), NHC, FRC + NHC, HFP + NHC, FRC + HFP + NHC, and CI groups. Samples were subjected to universal testing machine until the fracture occurred and failure mode was visually inspected. RESULTS: Mean and standard deviation of fracture resistance of the 7 groups ranged from 265.6 ± 68.0 N to 1023.7 ± 76.5 N. The highest reading was noted for intact teeth followed by FRC + HFP + NHC group and then the CI group, with no significant difference among the 3 groups. The lowest reading was noted for the ETP + MOD group. Maximum unrepairable fractures were seen in the ETP + MOD and CI groups. CONCLUSION: FRC + HFP + NHC combination and CIs increased the resistance to fracture of ETPs significantly.

A cone-beam computed tomographic analysis of total dentin removed, canal transportation, and canal-centering ability following instrumentation with three different file systems: An in vitro study.

Aims: The aim of this study was to evaluate the shaping ability following instrumentation with XP-endo Shaper (XPS), TruNatomy (TRN), and HyFlex CM (HCM) file system. Subjects and Methods: Fifty-four mesiobuccal canals of mandibular molars were selected and allocated into three groups randomly: XPS, TRN system, and HCM file system. Pre- and postinstrumentation scans were taken using a cone-beam computed tomography scanner to determine the amount of root dentin removed, mesiodistal and buccolingual transportation, and canal-centering ratio at 2, 5, and 8 mm from the root end. Statistical Analysis Used: Data were statistically analyzed using Kruskal-Wallis test and the significance level was set at P = 0.05. Results: TRN file system removed the least amount of root dentin. XPS showed statistically higher M-D canal transportation at 5 mm level from the apex. Conclusions: TRN file system showed better dentin preservation as compared to XPS and HCM. XPS showed the highest canal transportation at 5 mm. All three file systems performed similarly in terms of canal-centering ability.

The Resistance of Succedaneous Teeth to Periapical Infection: A Series of Seven Cases.

Pediatric dental procedures are carried out largely to prevent the adverse effects of primary teeth infection on succedaneous teeth (ST). The existing literature on how and when periapical infection (PI) from primary teeth affect ST is conflicted. A series of seven case reports on PI (abscesses and radicular cysts) from primary molars, until the eruption of the premolars, have been illustrated. The resistance of ST to PI based on their developmental stages is also discussed.

Comparative evaluation of sealing ability of two self-adhesive flowable composites following various restorative techniques in Class V lesions: An in vitro study.

Background: Self- adhesive flowable composite (SAFC) has been introduced to eliminate etching and bonding procedures. However, they have shown increased microleakage and poor bonding ability when used as per the manufacturer's instructions. It is unclear if prerestorative techniques can improve the same. Aims: This study aimed to evaluate the effects of acid etching, bevel placement and air abrasion on the marginal sealing ability of SAFCs when used in Class V restorations. Materials and Methods: 56 human mandibular premolars were taken and standard Class V cavities were prepared on the buccal aspect. They were divided into 4 groups comprising of control and three restorative techniques. Group A: SAFC used alone formed the control group, Group B: Acid-etched using 37.5% phosphoric acid gel, Group C: 1 mm bevel placed on the occlusal margin, Group D: Subjected to air abrasion. Each group was further subdivided into two, with one half being restored with Dyad flow (Kerr) while the remaining with Constic (DMG). The samples were thermocycled and the dye extraction method was used to assess microleakage using ultraviolet spectrophotometer. Statistical Analysis: Microleakage values were subjected to analysis of variance and post hoc analysis. Results: Statistically significant differences in the absorbance values were seen between the two SAFCs. Results with P < 0.05 were considered statistically significant. For Dyad flow, there was a statistically significant difference between Groups B and D (P = 0.028), while for Constic, it was between Groups A and B (P = 0.031) and Groups B and D (P = 0.025). CONCLUSIONS: Among restorative techniques, air abrasion showed the least microleakage, while acid etching showed the highest values. Among the two SAFCs, Constic presented lower microleakage than Dyad Flow.

Shear bond strength evaluation of an alkasite restorative material to three different liners with and without using adhesive system: An in vitro study.

AIMS: The aim of the study is to compare and evaluate the bonding ability of alkasite restorative material to TheraCal LC™ (TLC), Biodentine™ (BD), resin-modified glass ionomer cement (RMGIC) using an universal adhesive and characterizing their failure modes. SUBJECTS AND METHODS: Ninety extracted intact human molars were divided into three groups of (n = 30) as Group I (TLC), Group II (RMGIC), and Group III (BD). Each group was subdivided into two based on application of universal adhesive. Cention N was bonded to each sample. Shear bond strength analysis was performed. The data were analyzed using SPSS version 22 software. RESULTS: No significant difference was observed between Group I and Group II (P < 0.05) while Group III showed the least bond strength (P < 0.05). The modes of failure were predominantly cohesive in Groups I and III (TLC and BD) while RMGIC showed mixed and adhesive failures. CONCLUSIONS: The bond strength of Cention N to TLC and RMGIC was similar and significantly higher than that of BD following application of universal adhesive.

Management and 5-year follow-up of tooth with bilateral cemental tear and complete pulp canal obliteration.

The aim of this study is to report a rare case of bilateral cemental tear in a completely calcified tooth with successful dental management. A 60-year-old male reported with pain in the upper right central incisor. Radiographic examination revealed complete calcific obliteration of the root canal, inflammatory root resorption of apical third, and bilateral cemental tear and traumatic occlusion. Tooth mobility was within physiologic limits and 3-mm probing depth. Endodontic treatment of the tooth was carried out with intracanal calcium hydroxide therapy. The tooth was relieved of traumatic occlusion, scaling and root planning was carried out. As the tooth did not have any periodontal pocket, the maintenance phase was advised, and the tooth was kept under observation. After a follow-up of 5 years, the nonsurgical periodontal therapy showed satisfactory clinical and radiographic outcome.

Effect of bromelain enzyme on the microleakage of composite resin restorations after external tooth bleaching: An in vitro study.

AIMS: The aim of this study is to evaluate in vitro the effect of application of bromelain enzyme on the microleakage of composite resin restorations after external tooth bleaching using spectrophotometric evaluation. SUBJECTS AND METHODS: Buccal Class V cavities were prepared on the surface of fifty intact premolars, which were randomly divided into five groups. All cavities were filled with composite resin. Group I: Teeth were not bleached but restored (n = 10). External bleaching with 35% hydrogen peroxide was carried out for the rest of the specimensGroup II: Cavities were restored immediately after bleaching (n = 10)Group III: Cavities were restored after a delay of 3 weeks (n = 10)Group IV: Cavities were treated with sodium ascorbate after bleaching and then restored (n = 10)Group V: Cavities were treated with bromelain enzyme solution after bleaching and then restored (n = 10). Microleakage was assessed by the dye extraction method using a spectrophotometer. STATISTICAL ANALYSIS USED: The data were analyzed statistically by comparison of mean microleakage and post hoc test using SPSS 2.0 software. RESULTS: Group I displayed the least amount of microleakage, whereas Group II showed the greatest amount of microleakage (P < 0.05). Groups III, IV, and V showed a significantly lower amount of microleakage compared to Group II (P < 0.05). There was no statistically significant difference between Groups IV and V. CONCLUSIONS: Microleakage increased significantly after external bleaching with 35% hydrogen peroxide, and decreased when the bleached teeth were treated with antioxidants. Ten percent bromelain enzyme was effective in decreasing microleakage; however, its efficacy was similar to 10% sodium ascorbate.

Comparison between the Outcomes of Two Platelet-Rich Concentrates on Apexogenesis in Young Permanent Incisors Requiring Endodontic Retreatment.

Platelet-rich fibrin (PRF) and platelet-rich plasma (PRP) have been successfully used for inducing pulp regeneration in nonvital teeth. This case report highlights the difference between the outcomes of using PRF and PRP for pulp regeneration in a 13-year-old male patient, who had reported with endodontic treatment failure in his upper incisors. Gutta-percha and sealant were removed, and triple antibiotic paste (TAP) was placed in all the root canals and sealed with cavit. Subsequently, after TAP removal, 11 and 12 were treated with PRF, while 21 and 22 were treated with PRP. A resorbable matrix was placed over the PRF/PRP, over which mineral trioxide aggregate and glass ionomer cement were placed. After 2 years, all the upper maxillary incisors revealed dentinal wall thickening, root lengthening, and apical closure. However, apical bridge formation occurred only in incisors treated with PRF.

A cone-beam computed tomography assessment of the efficacy of different irrigation devices for removal of silicone oil-based calcium hydroxide from root canal system.

BACKGROUND: Most often used intracanal medicament is calcium hydroxide (Ca(OH)2). Removal of Ca(OH)2 before obturation is mandatory. Different irrigation solutions and devices were tested in the previous study for this purpose. AIM: The aim of this study was to evaluate the comparative efficacy of different irrigation techniques in removing intracanal medicament using cone-beam computed tomography (CBCT). MATERIALS AND METHODS: Cleaning and shaping was carried out in 42 freshly extracted single-rooted mandibular first premolars using Protaper Rotary Files. Intracanal medicament (silicone oil-based Ca(OH)2 paste) was placed and left for 2 weeks in the root canal. Medicament was then removed by five different irrigation techniques: EndoActivator, EndoVac, ultrasonic irrigation with Endo-U-File, F-file, and Max-i-Probe needle. Changes in volume percentage were measured using CBCT and results were statistically analyzed using Levene's statistics and ANOVA. RESULTS: Remnants of Ca(OH)2 were found in all experimental groups. No significant difference was detected among the groups. F-file showed maximum removal efficacy of approximately 48%. CONCLUSION: (1) There is no statistically significant difference between any irrigation technique for removal of oil-based Ca(OH)2. (2) F-file demonstrated better results among all the other systems.

Assessment of Enamel Remineralisation After Treatment with Four Different Remineralising Agents: A Scanning Electron Microscopy (SEM) Study.

INTRODUCTION: Decades of research has helped to increase our knowledge of dental caries and reduce its prevalence. However, according to World Oral Health report, dental caries still remains a major dental disease. Fluoride therapy has been utilised in a big way to halt caries progression, but has been met with limitations. This has paved the way for the development of newer preventive agents that can function as an adjunct to fluoride or independent of it. AIM: The purpose of the present study was to evaluate the ability of Casein Phosphopeptide-Amorphous Calcium Phosphate Fluoride (CPP ACPF), Bioactive Glass (BAG), fluoride enhanced Hydroxyapatite (HA) gel and self-assembling peptide P11-4 to remineralise artificial carious lesions in enamel in vitro using a 30 day pH cycling model through surface microhardness analysis and SEM. MATERIALS AND METHODS: Sixty enamel samples were divided into five groups of 12 samples each. The control Group A consisted of intact enamel samples, Group B: CPP-ACPF (Tooth Mousse Plus), Group C: BAG (SHY- NM), Group D: fluoride enhanced HA gel (ReminPro) and Group E: Self-assembling peptide P11-4 (Curodont Protect). All groups excluding the control group were subjected to demineralisation following which four of these groups were remineralised using the four remineralising agents. The treated groups were subjected to pH cycling over a period of 30 days. This was followed by assessment of surface microhardness and SEM for qualitative evaluation of surface changes. The results were analysed by One-Way Analysis Of Variance (ANOVA). Multiple comparisons between groups were performed by paired t-test and post-hoc Tukey test. RESULTS: The results of the study revealed that remineralisation of enamel was the highest in samples of Group E (Self assembling peptide P11-4) followed by Group B (CPP-ACPF), Group C (BAG) and Group D (fluoride enhanced HA gel). There was a significant difference (p<0.05) in the remineralising ability between the self assembling peptide P11-4 group and BAG and fluoride enhanced HA gel group. Although no significant difference was observed between the self assembling peptide P11-4 and CPP-ACPF group, the self assembling peptide P11-4 remineralised the enamel lesions more effectively. SEM photomicrographs of the test groups demonstrated either amorphous crystals or particles scattered on the surface or lines of remineralisation along the prismatic borders. CONCLUSION: Self assembling peptide P11-4 demonstrated promising results by effectively and significantly remineralising the enamel lesions as compared to other test agents.

A novel technique of sculpting Biodentine in the restoration of iatrogenic dentin loss.

Excessive tooth structure loss is a common iatrogenic error encountered during endodontic practice. Conservative treatment planning is essential to maintain the structural integrity in such teeth. This case report elucidates a novel approach in sculpting Biodentine as a dentin substitute followed by internal bleaching and restoration with fiber-reinforced composite.

Fibre reinforcement in a structurally compromised endodontically treated molar: a case report.

The reconstruction of structurally compromised posterior teeth is a rather challenging procedure. The tendency of endodontically treated teeth (ETT) to fracture is considerably higher than vital teeth. Although posts and core build-ups followed by conventional crowns have been generally employed for the purpose of reconstruction, this procedure entails sacrificing a considerable amount of residual sound enamel and dentin. This has drawn the attention of researchers to fibre reinforcement. Fibre-reinforced composite (FRC), designed to replace dentin, enables the biomimetic restoration of teeth. Besides improving the strength of the restoration, the incorporation of glass fibres into composite resins leads to favorable fracture patterns because the fibre layer acts as a stress breaker and stops crack propagation. The following case report presents a technique for reinforcing a badly broken-down ETT with biomimetic materials and FRC. The proper utilization of FRC in structurally compromised teeth can be considered to be an economical and practical measure that may obviate the use of extensive prosthetic treatment.

Endodontic Management of a Mandibular First Molar with Radix Entomolaris and Conservative Post-endodontic Restoration with CAD/CAM Onlay: A Novel Clinical Technique.

This case report describes a novel technique of restoring endodontically treated teeth. Hidden caries causing irreversible pulpitis in a mandibular molar with Radix Entomolaris (RE) was evident. The intact occlusal surface anatomy was duplicated before preparing an access cavity to replicate the original occlusal surface in the post endodontic restoration using (Computer-Aided Design and Computer-Aided Manufacturing) CAD/CAM technique. This report highlights uniquely designed onlay utilizing the benefits of contemporary materials and advanced technology.

Assessment of apical seal obtained after irrigation of root end cavity with MTAD followed by subsequent retrofilling with MTA and Biodentine: An in vitro study.

INTRODUCTION: The present study is designed to assess the apical seal obtained after root end cavity irrigation with MTAD and retrograde filling with mineral trioxide aggregate (MTA) and Biodentine. MATERIALS AND METHODS: Sixty extracted maxillary central incisors were instrumented and obturated. Apical 3 mm of all the roots were resected and retrograde preparations of 3 mm were made in all the teeth using ultrasonic tips. Thirty root end preparations were irrigated with MTAD for 5 min (Group 1), while 30 were irrigated with saline for 5 min (Group 2). Each main group was subdivided into two subgroups containing 15 samples each. Samples under each subgroup were then filled either with MTA (1A and 2A) or Biodentine (1B and 2B). The amount of microleakage was assessed using a UV spectrophotometer. RESULTS: Statistical analysis suggest a significant difference (P < 0.005) between group 1A and 2A and between the groups 1B and 2B (P < 0.1). There was a significant difference (P < 0.005) between group 1A and 1B and also between group 2A and 2B. CONCLUSION: Irrigation with MTAD significantly improved the apical seal of Biodentine, but it increased the microleakage in MTA-filled root end cavities. Also the apical seal obtained with Biodentine was superior to that obtained with MTA.

Treatment of combined endodontic: periodontic lesion by sealing of palato-radicular groove using biodentine.

INTRODUCTION: Palatoradicular groove is a developmental anomaly which is predominantly found in maxillary lateral incisors. It provides a susceptible alcove for the progression of localised periodontal inflammation which can further cause pulpal involvement. This case report describes the successful treatment of a large periodontic - endodontic lesion usingnon surgical endodontic therapy and biodentine for the sealing of the palatoradicular groove.

A comparison between three different pit and fissure sealants with regard to marginal integrity.

AIM: THE AIM OF THIS STUDY IS TO COMPARE THE OCCURRENCE OF ENAMEL FRACTURES, SEALANT FRACTURES AND MARGINAL FISSURES AFTER PLACEMENT OF THREE SEALANTS: Helioseal F, Conseal F and Clinpro. MATERIALS AND METHODS: Thirty individuals between 13 and 15 years of age, diagnosed with pit and fissure caries by visual and DIAGNOdent examination, were chosen for sealant placement on their mandibular molars. The sealants were placed at random, after which, impressions were made with polyvinyl siloxane and casts were fabricated. Dies were prepared, each of which were sputter coated with gold in order to be examined under a scanning electron microscope. The following morphologies were analyzed from dies from each of the sealant groups: Continuous margins, sealant fractures, marginal fissures and enamel fractures. After six months, they were recalled for impression making. Dies were prepared and microscopically analyzed as mentioned. Based on the time of evaluation, there were two groups: Initial group (soon after placement) and final group (after six months). Statistical analysis was done using the paired 't' test and One-way analysis of variance (ANOVA). RESULTS AND CONCLUSIONS: Clinpro had the greatest fracture resistance, followed by Conseal F and Helioseal F. The occurrence of marginal fissure was found to be least with Clinpro.

an in vitro study comparing the intracanal effectiveness of calcium hydroxide- and linezolid-based medicaments against Enterococcus faecalis.

INTRODUCTION: This study evaluated the efficacy of calcium hydroxide (CH), Vitapex (VP), linezolid (LZ), a combination of LZ with CH (LC), and a control group (N, no medicament) against Enterococcus faecalis (EF). METHODS: Human single-rooted premolars were instrumented up to ProTaper size F3 files. EF suspension was inoculated into each root specimen and incubated. The medicaments were syringed into each root by weight and incubated. After 72 hours, 6 samples per group (among the 5 groups) were retrieved. A hole was drilled on each root, and the dentinal shavings obtained were allowed to fall in brain-heart infusion (BHI) broth. Dilutions from the broth were plated and spread over BHI agar and blood agar. Colony-forming units (CFU) of EF were measured from BHI agar. The procedure was repeated after 8 days and 14 days. RESULTS: In group CH, the mean CFU (log 10 values) after 72 hours, 8 days, and 14 days were 1.17 ± 1.16, 3.33 ± 1.97, and 4.17 ± 1.17, respectively (statistically significant). In group VP, the mean CFU were 0.83 ± 0.75, 4.00 ± 1.67, and 4.83 ± 1.72. In group LZ, the mean CFU at 72 hours and after 8 days was 0.17 ± 0.41, and no CFU were found on the fourteenth day. Similarly, in group LC, the mean CFU at 72 hours and after 8 days was 0.50 ± 0.84, which increased to 1.33 ± 1.51 on the fourteenth day (not significant). CONCLUSIONS: LZ was found to be most effective on EF, followed by LC, CH, and VP.

An in vitro comparison between the apical sealing abilities of resilon with Epiphany sealer and gutta-percha with AH plus sealer.

CONTEXT: The study assesses the apical sealing ability of two obturating materials (resilon and gutta-percha) with their sealants by means of the dye penetration method using India ink. AIMS: To compare the resistance to apical dye penetration between resilon (with Epiphany sealer; Epiphany, Pentron clinical technologies, USA) and gutta-percha (with AH Plus sealer; Dentsply, Maillefer, Germany). It was hypothesized that there would be no difference between the two groups with regard to apical dye penetration. SETTINGS AND DESIGN: Hundred mandibular first premolars from individuals aged between 20 to 25 years were selected after their lengths were standardized. MATERIALS AND METHODS: Instrumentation was performed with NiTi hand protaper files (Dentsply, Maillefer) using EDTA paste and copious irrigation with 2.5% sodium hypochlorite. Experimental group 1 consisted of roots that were treated with Epiphany primer and obturated with resilon (with Epiphany sealer). Experimental group 2 consisted of those obturated with gutta-percha using AH Plus sealer. The samples were immersed in blue India Ink and cleared using 5% nitric acid. Dye penetration was assessed under a stereomicroscope. STATISTICAL ANALYSIS: Mann-Whitney U test. RESULTS: Roots obturated with resilon core material and Epiphany sealer exhibited lesser mean apical dye penetration (1.281 mm; SD: 0.742) in comparison to those obturated with gutta-percha and AH plus sealer (2.154 mm; SD: 0.814). The difference was found to be highly significant (P<0.0025). CONCLUSION: Resilon (with Epiphany sealer) provided better radicular apical sealing in comparison to gutta percha (with AH Plus sealer).

In vitro resistance to fracture of roots obturated with Resilon or gutta-percha.

INTRODUCTION: There have been varied results from studies comparing postendodontic fracture resistance between teeth obturated with Resilon or gutta-percha. This study was performed to evaluate the fracture resistance of roots obturated by using Resilon (RealSeal system) or gutta-percha (with AH Plus sealer). METHODS: Eighty extracted human mandibular single-rooted premolars stored in 10% formalin were used in the study. They were prepared by using a crown-down technique, debrided with NaOCl, ethylenediaminetetraacetic acid, and sterile water and divided into 4 groups. Obturation was performed by using the lateral condensation method. The negative control group consisted of unfilled specimens, and the positive control group consisted of those obturated with flowable, dual-cure composite resin. All root specimens were stored for 2 weeks in 100% humidity to allow complete setting of the sealer. Each specimen was mounted in acrylic in a polyvinyl ring and tested for fracture resistance with the Universal testing machine. The loading fixture of the machine was mounted with its spherical tip aligned with the center of the canal opening of each root. A vertical loading force was applied until it fractured the root. The force values were subjected to statistical analysis including analysis of variance and Fisher least significant difference testing. RESULTS: Teeth obturated with Resilon were more resistant to fracture than those obturated with gutta-percha. The difference was found to be highly significant (P=.00001). CONCLUSIONS: Resilon increased the resistance to fracture of single-rooted teeth in vitro.