PEEK and Glass Fiber Post Pushout Bond Strength and Vickers hardness of Canal disinfected with Curcumin photosensitizer activated by Microbubble emulsion and Sodium-hypochlorite with EDTA.

AIMS: Impact of different post-space disinfectants (Saline, Sodium hypochlorite (NaOCl) followed by ethylene-diamine-tetra-acetic acid (EDTA) and curcumin activated by microbubble emulsion (MBE) on the Vickers hardness (VH) of root canal dentin and extrusion bond strength (EBS) of Glass fiber post (GFP) and PEEK post. METHODS: Ninety maxillary central incisors having fully formed roots were included. After the specimen's disinfection, root canal treatment was completed. Post space was prepared by removing gutta-percha using gates glidden drills. Teeth were then arbitrarily allocated into three groups based on the methods of disinfection regime used. Group 1: Saline, Group 2: NaOCl+ EDTA and Group 3: Curcumin activated by MBE (n=30). Analysis of VH of radicular dentin was performed using a micro-Vickers tester on ten samples from each group. After post-space disinfection, twenty specimens from each group were further divided into two subgroups (n=10) In group-1A 2A, and 3A, GFP was used. Whereas, prefabricated PEEK posts were used in 1B, 2B, and 3B subgroups. The PBS and failure modes were performed using a universal testing machine and stereomicroscope respectively. Data was analyzed using ANOVA and Tukey post hoc test to identify significant variations among groups concerning the MH and EBS of the different posts used (p=0.05). RESULTS: Group 2 (5.25% NaOCl + 17% EDTA) (0.15 ± 0.02 GPa) treated specimens presented lowest scores of VH. However, Group 1 (Saline) irrigated canals displayed the highest scores of surface hardness (0.25± 0.07 GPa). Additionally, a cervical third of 3A (CP activated by MBE + GFP) (11.22±0.79 MPa) presented the highest scores of bond integrity. Whereas Group 1B (Saline + PEEK post) treated specimens presented the lowest scores of PBS (4.15±0.15 MPa). CONCLUSION: Curcumin activated by microbubble emulsion for disinfection of canal dentin demonstrated favorable VH. Similarly, glass fiber post-cemented in radicular walls disinfected with curcumin activated with MBE showed promising post-bond integrity to the canal dentin.

Effect of canal medicaments triple antibiotic paste, Bio-C Temp, and Nano-silver gel activated by visible blue light on canal dentin microhardness and extrusion bond strength of AH plus sealer: A SEM and EDX analysis.

AIM: Assessment of contemporary canal medicaments (Triple antibiotic paste (TAP), Bio-C Temp, and Nano silver gel activated by visible blue light on the dentin microhardness (MH) and push-out bond strength (PBS) of AH plus endodontic sealer. METHOD: Sixty extracted premolars were obtained and decontaminated. Canal cleaning and shaping were performed. The samples were randomly allocated into four groups based on the intracanal medicaments. Group 1= CH paste, Group 2= TAP, Group 3= Bio-C Temp, and Group 4= Nano-silver gel activated by visible blue light. MH assessment was performed using a Vickers Microhardness tester. Forty specimens, ten from each group underwent root canal obturation. PBS and failure mode evaluation were performed. ANOVA and Post Hoc Tukey test were utilized to conduct intra and inter-group comparisons. RESULTS: The maximum outcome of surface hardness was presented by Group-3 (Bio-C Temp®) specimens. However, minimum scores of MH were displayed by Group 1 (CH) treated teeth. The highest outcomes of EBS were exhibited by the cervical third of Group 3 (Bio-C Temp®) samples. The apical section of Group 4 Teeth with Nano Silver gel activated by visible blue light revealed the lowest scores of bond integrity. CONCLUSION: Bio-C Temp and TAP proved to be better intracanal medicament than other tested groups in terms of the push-out bond strength of the sealer. TAP displayed lower microhardness as compared to the Bio-C Temp.

The effectiveness of dental water jet in reducing dental plaque and gingival bleeding in orthodontic patients: A systematic review and meta-analysis of randomized clinical trials.

INTRODUCTION: This systematic review and meta-analysis tests the effectiveness of dental water jet (DWJ) with manual toothbrushes (MTB) compared to MTB alone in oral health maintenance in orthodontic patients. METHODS: Four databases were systematically searched: PubMed, Scopus, Web of Science (WoS) and Cochrane Library until 6 January 2022 using a combination of medical subject heading (MeSH) terms and keywords. Randomized clinical trials (RCTs) were only included and critically appraised using the Cochrane Risk of Bias (ROB) tool. The mean difference (MD) effect measure was calculated using the Mantel-Haenszel statistical test (95% confidence interval [CI]) to compare both study groups (p-value < 0.05). RESULTS: After reviewing 5881 studies from a systematic search, six were selected for inclusion, with four involved in the quantitative analysis. The risk of bias was low in two studies, moderate in two studies and high in the remaining two studies. The meta-analysis showed a significant improvement in plaque index and bleeding scores in DWJ + MTB group compared MTB alone group in orthodontic patients with generalized gingivitis (MD = -0.75, 95% CI [-1.29, -0.22], p = 0.006) and (MD = -0.17, 95% CI [-0.27, -0.08], p = 0.0003), respectively. However, no significant improvement was detected between both groups in the gingival index. CONCLUSIONS: The use of DWJ as an adjunctive device in addition to MTB can be an effective strategy for maintaining oral hygiene in orthodontic patients with gingivitis. However, more high-quality RCTs are needed to confirm the findings.

Bleached enamel reversal using grape seed extract, green tea, curcumin-activated photodynamic therapy, and Er: YAG on microleakage and bond integrity of composite material bonded to the enamel surface.

AIMS: Bleached enamel reversal using antioxidants sodium ascorbate (SA), Green tea extract (GTE), grape seed extract (GSE), Curcumin photosensitizer (CP) and Er: YAG laser on the adhesive strength and marginal leakage of composite material bonded to the bleached enamel surface. MATERIALS AND METHODS: Enamel surface of hundred and twenty sound human first premolar teeth was cleansed using pumice and bleached with 35 % hydrogen peroxide. The samples were randomly divided into 5 groups based on the antioxidants used. n = 20 Group 1 (Control): No antioxidant agent, Group 2: 10 % SA solution, Group 3: 6.5 % GSE, Group 4: 5 % GTE, Group 5: Er: YAG laser and Group 6: CP. Following reversal, the composite was built and cured for 40 s. All the specimens were stored in distilled water at room temperature for 1 day. Microleakage, SBS, and failure mode were analyzed. Kolmogorov-Smirnov test, one-way analysis of variance, and Tukey's multiple post hoc test were used to analyze the data statistically. RESULTS: Group 2 (SA) (20.11 ± 5.79 nm) exhibited minimum value of microleakage and highest SBS (10.22 ± 1.62 MPa). Whereas, Group 1 (No antioxidant agent) displayed maximum scores of marginal leakage (28.11±8.89 nm) and lowest SBS (7.02 ± 1.22 MPa). CONCLUSION: CP, GTE and GSE can be used as a potential alternative to the commonly used SA solution to reverse the negative impact of bleaching on the enamel surface. The use of reversal agents CP, GTE and GSE improves bond values with a decrease in microleakage scores However, future studies are still warranted to conclude the outcomes of the existing study.

Poly-Ether Ether-Ketone Post Conditioned with Sulfuric Acid, Rose Bengal Activated by Photodynamic Therapy and Sandblasting on Pushout Bond Strength to Radicular Dentin Luted with Methyl Methacrylate and Composite-Based Cement.

Objective: Assessment of post surface conditioners [sulfuric acid (SA), Rose Bengal (RB), and sandblasting (SB)] and different luting cements [methyl methacrylate (MMA)-based cement and composite-based cement] on pushout bond strength (PBS) of poly-ether ether-ketone (PEEK) post bonded to canal dentin. Materials and methods: Endodontic treatment was performed on 120 single-rooted human premolar teeth. The preparation of the post space was performed and 4 mm of gutta-percha was retained in the apical region of the root. One hundred and twenty PEEK posts were fabricated from a PEEK blank utilizing a Computer aided design-Computer aided manufacture (CAD-CAM) system. The PEEK posts were allocated randomly into four groups based on post surface conditioning (n = 30). Group A: SA, Group B: RB, Group C: SB, and Group D: No conditioning (NC). Each group was further divided into two subgroups based on the luting cement used for bonding (n = 15). Group A1, B1, C1, and D1 specimens were cemented using composite-based resin cement. However, Group A2, B2, C2, and D2 posts were luted with MMA-based resin cement. PBS assessment using a universal testing machine was performed. Failure modes were analyzed under a stereomicroscope. The data relating to the effects of surface treatment and luting types of cement were analyzed using one-way analysis of variance (ANOVA) and Tukey's post hoc test (p = 0.05). Results: Coronal section of Group B2: RB+Super-Bond C&B [9.61 ± 0.75 megapascals (MPa)] displayed the highest bond scores of PEEK after root dentin. Whereas it was also discovered that Group D1: NC+Panavia®V5 (2.05 ± 0.72 MPa) presented the lowest PBS scores. Intergroup comparison analysis revealed that Group A2: SA+Super-Bond C&B and Group B2: RB+Super-Bond C&B displayed no significant difference in their bond scores. Conclusions: RB and SA possess the potential to be used as a PEEK post conditioner. MMA-based cement displayed better performance than composite-based cement.

Effect of malachite green, ocimum sanctum, and Er, Cr: YSGG laser on antimicrobial activity against S.mutans and CAD disinfection bonded to resin restoration.

AIMS: Evaluation of survival of S.mutans and shear bond strength (SBS) of adhesive restorative material bonded to carious affected dentin (CAD) after using cavity disinfectant i.e., Er, Cr: YSGG (ECYL), (Nd: YAG) (NYL), Malachite green (MG), Ocimum sanctum (OS) in comparison to the conventional control chlorhexidine gluconate (CHX). MATERIALS AND METHODS: Seventy-five caries-affected mandibular third molars having ICDAS scores 4 and 5 were included. Carious infected dentin was eliminated and CAD surface was obtained. On twenty-five samples, an uncontaminated suspension of S. mutans strain ATCC 35,668 in Brain-Heart Infusion broth (BHI) was obtained after 12 h of incubation at 37 °C. Based on the disinfection regime used to sterilize the CAD surface, all the specimens were allocated into five different groups. (n = 15) Group 1: CAD disinfected with CHX, Group 2: CAD disinfected with ECYL, Group 3: CAD disinfected with NYL, Group 4: CAD disinfected with MG, and Group 5: CAD disinfected with OS. An assessment of the survival rate of S. mutans was performed. Fifty specimens were smeared with single-step adhesive bond followed by restoring the CAD surface using packable composite. SBS and failure mode were determined using a universal testing machine and stereomicroscope at 40x magnification. ANOVA and post-hoc Tukey-Kramer test was used for data analysis p = 0.05. RESULTS: Group 1: CHX-treated specimens displayed the lowest bacterial viability (0.11±0.03 CFU/mL). However, group 4: MG exhibited the highest bacterial survival (0.15 ± 0.09 CFU/mL). The highest and lowest SBS of resin adhesive bonded to disinfected CAD surface were exhibited by (group 5: OS) (21.48±1.39 MPa) and (group 3: NYL) (16.41±0.90 MPa) respectively (p>0.05). CONCLUSION: Ocimum sanctum seems to be promising in terms of its antibacterial efficacy against S.mutans and positive impact on SBS of resin adhesive to CAD surface.

Effectiveness of final cavity disinfectant terminalia chebula, malachite, and indocyanine green, against E. Faecalis and on the bond interface of fiber post to radicular dentin.

AIMS: Evaluation of antimicrobial efficacy of contemporary disinfection Malachite green (MG), Terminalia chebula (T. chebula), and Indocyanine green (ICG)) against E. faecalis and their effect on push-out bond strength (PBS) of glass fiber post (GFP) bonded to root dentin in comparison to conventional irrigation used (Sodium hypochlorite (NaOCl) + Ethylene diamine tetraacetic acid (17% EDTA). MATERIALS AND METHODS: Root canal treatment was initiated on sixty human single-rooted premolars and working length was established. The canals were enlarged using ProTaper universal system till F3. The prepared canals were obturated with Gutta-percha (GP) and AH Plus sealer followed by post-space preparation. Twenty canals contained a standard strain of E. faecalis (n=5 in each group) cultured overnight at 37 °C in BHI broth. All the samples were randomly allocated into four groups based on post-space irrigation. (n = 10) Group 1: 5.25% NaOCl+17% EDTA (Control), Group 2: 5.25% NaOCl + ICG, Group 3: 5.25% NaOCl + MG and Group 4: 5.25% NaOCl + T. chebula. Survival rates of E. faecalis were evaluated on the twenty specimens. GFP was placed on the remaining samples using self-etch dual-cure pastes and sectioning was performed in 1 mm thick slices. PBS and failure mode were analyzed using a universal testing machine and stereomicroscope. One-way analysis of variance (ANOVA) and Tukey multiple comparison t-tests were used for data analysis. (p = 0.05). RESULTS: 5.25% NaOCl+17% EDTA demonstrated (0.11±0.01 CFU/mL) the lowest survival rate of E. faecalis. However, Group 2 (5.25% NaOCl + ICG) exhibited the highest survival rate (0.52 ± 0.10). Furthermore, the coronal third of group 4 (5.25% NaOCl + T. chebula) (8.71±0.25 MPa) specimens demonstrated the highest PBS of GFP. However, an apical section of group 2 samples (5.25% NaOCl + ICG) (1.21±0.71 MPa) displayed the lowest outcome of bond integrity. CONCLUSION: Terminalia chebula when used as a final canal disinfectant seems to be promising in improving canal sterility and the bond strength of GFP to the root dentin.

Comparative Evaluation of Microleakage of Flowable Composite Resin Using Etch and Rinse, Self-Etch Adhesive Systems, and Self-Adhesive Flowable Composite Resin in Class V Cavities: Confocal Laser Microscopic Study.

The essential factor in determining the preservation of restoration is the marginal seal. Restoring cervical lesions with a resin composite has always been a challenge. Composite resins with various viscosities and different bonding systems are being researched to reduce the microleakage. Confocal laser scanning microscopy (CLSM) is the latest non-destructive technique for visualizing the microleakage. Objectives: To evaluate and compare the microleakage of Universal Flo composite resin (G-aenial) using etch and rinse adhesive system ER-2 steps (Adper Single Bond 2), self-etch adhesive system SE-1 step (G-Bond), and self-adhesive flowable composite resin (Constic) in Class V cavities using a confocal laser scanning microscope. Materials and Method: Class V cavities were prepared on 27 caries-free human extracted premolar teeth on the buccal and lingual surfaces with standardized dimensions of 2 mm height, width 4 mm, and a depth of 2 mm. After the cavity preparation, all teeth were randomly divided into three groups, namely Group-I: G-aenial Universal Flo with Single Bond 2 (n = 9 teeth); Group-II: G- aenial Universal Flo with G-Bond (n = 9 teeth), and Group-III: Constic (n = 9 teeth). The prepared and restored specimens were then subjected to thermocycling for 500 cycles in a water bath at 5 °C and 55 °C with a dwelling time of 30 s. The specimens were placed in 0.6% aqueous rhodamine dye for 48 h. Sectioning was carried out bucco-lingually and specimens were evaluated for microleakage under a confocal laser scanning microscope. Results: There was a significant difference (p = 0.009) in microleakage when comparing total etch and rinse, specifically between Adper Single Bond 2 ER-2 steps (fifth generation) and self-adhesive flowable composite resin, which is Constic. There was more microleakage in the self-etch bonding agent, particularly G-Bond, SE-1 step (seventh generation), when compared to ER-2 steps (fifth generation bonding agent); however, the results were not statistically significant (p = 0.468). The self-adhesive flowable composite resin showed more microleakage than SE-1 step and ER-2 steps. Conclusions: None of the adhesive systems tested were free from microleakage. However, less microleakage was observed in the total etch and rinse, especially Adper Single Bond 2 (ER-2 steps), than the self-etch adhesive system SE-1 step and self-adhesive flowable composite resin. Clinical significance: Constant research and technological advancements are taking place in dentin adhesives to improve the marginal seal. This has led to the evolution of total acid-etching dentin bonding agents termed as etch and rinse (ER)-2 steps (fifth generation dentin bonding agents) and self-etching (SE) 2 steps, and SE-1 step dentin bonding agents termed as the sixth and seventh generation bonding agents, respectively.

Radicular canal disinfection using photon-induced photoacoustic streaming and riboflavin photosensitizer to silver diamine fluoride and diode laser bonded to fiber post: An assessment of extrusion bond strength.

AIM: The present study aimed to estimate and compare the effectiveness of different innovative canal cleansing approaches photon induced photoacoustic streaming (PIPS) Riboflavin Photosensitizer (RF), Diode Laser, and silver diamine fluoride (SDF) on push out bond strength (PBS) of fiber post cemented to radicular dentin MATERIAL AND METHODS: Forty extracted premolars were disinfected and decoronated up to the cement-o-enamel junction. Canals of all specimens were cleaned and shaped utilizing a reciprocating system. Post space was created by employing peso-reamers and samples were randomized into four groups based on methods of disinfection (n = 10). Group 1 (PIPS), group 2 (Diode Laser), group 3 (RP), and group 4 (SDF) canal disinfection. Fiber posts were cemented via Self etch resin cement (SERC) in a radicular dentin post space area and root was segmented at three levels (coronal, middle and apical). PBS analysis was performed, and a stereomicroscope was used to assess the failure mode. The means and standard deviations of PBS among studied groups were measured using one-way analysis of variance (ANOVA) after exposure. The means of bonding strength were compared by Tukey multiple comparison tests (p > 0.05). RESULTS: RF had the highest PBS at all three root levels, coronal (8.31 ± 0.64 MPa), middle (8.13 ± 0.11 MPa) and apical (5.68 ± 0.54 MPa) while group 4 SDF samples showed lowest PBS at all root portions, coronal (6.14 ± 0.78 MPa), middle (5.18 ± 0.15 MPa) and apical (3.15 ± 0.19 MPa), respectively. Intergroup comparison unveiled comparable PBS at all three root levels for group 1 (PIPS) and group 3 RF (p > 0.05). Intragroup comparison displayed a significant decline in PBS values from coronal, middle to the apical direction in all studied groups CONCLUSION: Disinfection of radicular dentin with Riboflavin Photosensitizer and photon-induced photoacoustic streaming bonded to fiber post have the greatest PBS at all three levels cervical, middle and apical.

Influence of curing duration and mixing techniques of bulk fill resin composites on bi-axial flexural strength and degree of conversion.

OBJECTIVES: The aim was to assess the influence of polymerization duration, method and resin manipulation techniques on the biaxial flexural strength (BFS) and degree of conversion (DC) of bulk fill resin composites (BFRC). METHODS: One hundred and eighty disc specimens were fabricated using MultiCore (MC) and Core-It (CI) bulk fill resin composite. Each material group, specimens were divided into nine subgroups based on curing methods (Light cure for 10 and 20 s; and auto-cure) and mixing techniques (first auto-mix, second automix, and hand mix). BFS was tested with a ball indenter at a crosshead speed of 0.50 mm/min. DC was assessed for MC and CI materials for 10 s and 20 s light cure; and auto cure specimens using Fourier Transform-Infrared Spectroscopy (FTIR). Statistical data comparisons were performed using ANOVA, Bonferroni and Tukey-Kramer tests. RESULTS: For MC and CI, BFS was highest in 10 s light cure specimens, however comparable to specimens cured for 20 s (p > 0.05). Auto cure specimens showed lower BFS than light cured samples for both materials (p < 0.05). Hand mixed specimens showed significantly compromised BFS compared to automix technique for MC and CI. DC % was comparable for 10 s and 20 s light cure methods for both materials (p > 0.05), which was higher than DC % of auto cure bulk fill resins (p < 0.05). CI showed higher DC % and BFS compared to MC bulk fill resin composite. CONCLUSION: Photo-polymerization duration of 10 and 20 s showed similar outcomes for BFS and DC %; and BFS for auto-mixed resins (MC and CI) was significantly higher than hand mixed resin. BFS and DC was higher in photopolymerized groups as compared to auto-cured resin regardless of the manipulation technique for both materials (MultiCore and Core it).

Graphene oxide nano-filler based experimental dentine adhesive. A SEM / EDX, Micro-Raman and microtensile bond strength analysis.

AIM: The study aimed to assess graphene oxide (GO) adhesive and its dentin interaction using scanning electron microscopy (SEM), MicroRaman spectroscopy and Microtensile bond strength (µTBS). MATERIALS AND METHODS: Experimental GOA and control adhesives (CA) were fabricated. Presence of GO within the experimental adhesive resin was assessed using SEM and Micro-Raman spectroscopy. Ninety specimens were prepared, sixty teeth were utilized for µTBS, twenty for SEM analysis of interface for CA and GOA and ten were assessed using microRaman spectroscopy. Each specimen was sectioned and exposed dentine was conditioned (35% phosphoric acid) for 10 s. The surface was coated twice with adhesive (15 s) and photopolymerized (20 s). Composite build-up on specimen was photo-polymerized. Among the bonded specimens, thirty specimen were assessed using Micro-Raman spectrometer, SEM and energy dispersive X-ray spectroscopy (EDX), whereas remaining specimens were divided in to three sub-groups (n = 10) based on the storage of 24 h, 8 weeks and 16 weeks. µTBS testing was performed at a crosshead speed of 0.5 mm/min using a microtensile tester. The means of µ-tbs were analyzed using ANOVA and post hoc Tukey multiple comparisons test. RESULTS: No significant difference in µTBS of CA and GOA was observed. Storage time presented a significant interaction on the µTBS (p < 0.01). The highest and lowest µTBS was evident in CA (30.47 (3.55)) at 24 h and CA (22.88 (3.61)) at 18 weeks. Micro-Raman analysis identified peaks of 1200 cm-1 to 1800 cm1, D and G bands of GO nanoparticles in the resin. Uniform distribution of graphene oxide nanoparticles was present at the adhesive and hybrid layer. CONCLUSION: GO showed interaction within adhesive and tooth dentin similar to CA, along with formation of hybrid layer. In ideal conditions (absence of nanoleakage), graphene oxide modified adhesive shows comparable bond strength and durability of resin dentine bond.

Repair strength and surface topography of lithium disilicate and hybrid resin ceramics with LLLT and photodynamic therapy in comparison to hydrofluoric acid.

AIM: The aim was to compare the repair bond strength and surface topography of lithium disilicate ceramics (LDC) and hybrid resin ceramics (HRC) using different surface conditioning treatments [low level laser therapy (LLLT), photodynamic therapy (PDT), hydrofluoric acid (HF) with silane and air abrasion (AA) and silane]. MATERIAL AND METHOD: Sixty specimens each of LDC and HRC were used. Discs were prepared for each group (6 × 2 mm), conditioned using different regimes. Specimens in group 1 and 5 were laser irradiated using Er,Cr:YSGG (ECYL), group 2 and 6 were conditioned using methylene blue photosensitizer (PDT), group 3 and 7 surface was treated with hydrofluoric acid and silane (HFA-S), group 4 and 8 conditioned with Al2O3 air abrasion and silane (AA-S). A Porcelain Repair Kit was used according to manufacturer recommendation in all samples. Peak universal bond adhesive was rubbed on ceramic surface and then bonded with composite resin. For shear bond strength testing the specimens were placed in a universal testing machine. A stereomicroscope at 40x magnification was used to analyse failure pattern. Five specimens in each group after surface treatment were evaluated for surface changes and topography using scanning electron microscopy. The mean repair bond strength was calculated using ANOVA and Tukey's post hoc test at a significance level of (p < 0.05). RESULT: The highest repair bond strength was observed in group 3 (LDC) (20.57 ± 3.58 MPa) (HFA-S), whereas, the lowest score was displayed in Group 2 (LDC) using methylene blue photosensitizer (MBPS) (12.18 ± 1.08 MPa). Similarly, in HRC the highest repair SBS was presented in group 8 (AA-S) (20.52 ± 2.51 MPa) and the lowest SBS values were exhibited by PDT treated group 6 (13.22 ± 0.62 MPa). CONCLUSION: A combination of mechanical and chemical surface treatments should be used in order to achieve adequate repair bond strength between resin composites and ceramic interface of LDC and HRC.

Antimicrobial efficacy of silver diamine fluoride in comparison to photodynamic therapy and chlorhexidine on canal disinfection and bond strength to radicular dentin.

AIM: To assess the antimicrobial efficacy of Silver diamine fluoride (SDF), Sodium hypochlorite (NaOCl), Chlorhexidine (CHX) and Photodynamic therapy (PDT) in radicular dentin and subsequent bond strength of Fiber reinforced composite post (FRCP) to radicular dentin. MATERIAL AND METHODS: Forty extracted premolars were disinfected and decoronated up-to cement-o-enamel junction (CEJ). Canals were instrumented using crown-down technique, dried and filled with gutta percha. Post space was prepared with the help of peso reamers and inoculated with E. faecalis. Samples were randomly allocated into four groups based on chemical irrigation (n = 10). Group 1, canal disinfected with (PDT, MB), group 2 (5.25 % NaOCl +17 % EDTA), group 3 (3.8 % SDF) and group 4 (CHX). Specimens were tested with confocal laser scanning microscopy analysis (CLSM) to confirm the presence of E. faecalis. Fibre post were luted in root canal and sectioned at three levels (apical, middle and coronal). Push-out test was performed and failure analysis of debonded surfaces was evaluated using stereomicroscope. Live and dead cells after exposure were calculated in percentage. One-way analysis of variance (ANOVA) assessed the means and standard deviations of extrusion bond strength (EBS). Tukey multiple comparison tests was used to compare means of bond strength (p = 0.05). RESULTS: The maximum antimicrobial efficacy against E. faecalis was observed in group 2 which included canal disinfected with 5.25 % NaOCl and 17 % EDTA (64.41 ±â€¯1.22). Similarly, CHX showed lowest effectiveness as canal irrigant against E.faecalis (58.29 ±â€¯2.41). Intragroup comparison revealed highest bond strength for group 2 at all three level. Similarly, the lowest EBS was found in CHX group. Inter-group comparison confirmed comparable EBS at all root levels (apical, middle and coronal) for group 2 and group 3 (p > 0.05). CONCLUSION: Radicular dentin treated with 5.25 % NaOCl and 17 % EDTA displayed highest antimicrobial and bond strength scores. SDF and PDT can potentially be used in canal irrigation.

Management of caries affected dentin (CAD) with resin modified glass ionomer cement (RMGIC) in the presence of different caries disinfectants and photosensitizers.

AIM: To evaluate Shear bond strength (SBS) of resin modified glass ionomer cement (RMGIC) on caries affected dentin after using different cavity disinfectants i.e., chlorhexidine gluconate (CHX), Er,Cr:YSGG laser (ECYL) and photodynamic therapy (PDT). MATERIAL AND METHODS: Total 50 freshly extracted mandibular molars were obtained through non-traumatic extraction. All the samples were rooted vertically within self-cure acrylic resin blocks up to cervical level so that only coronal portion remain visible. Silicon carbide grinding discs 1200 and 600 grits was used to prepare the teeth. However affected dentin remains untouched. All samples were randomly distributed in to five groups (n = 10). Group 1: 2 % CHX, Group 2: 2 % solution of methylene blue (MB) and Diode laser, Group 3: Indocyanine green (ICGP) solution and Diode laser, Group 4: curcumin (CP) and LED curing unit, Group 5: ECYL. The specimens were then stored at a temperature of 37 °C for 24 h and 100 % humidity before specimens were placed in to universal testing machine for the SBS measurements. Failure mode examination was performed by a stereomicroscope. ANOVA test analyze inter group comparison. Tukey HSD test was used to analyze multiple group comparison. The level of significance was set at p < 0.05 value. RESULTS: Among all the groups, group 1 (control, CHX treated) demonstrated highest SBS value (18.31 ±â€¯1.06 MPa). Whereas lowest SBS was displayed by group 2 (PDT, MB) (12.31 ±â€¯0.57 MPa). Dentin disinfected with group 4 (PDT, CP) (16.86 ±â€¯0.97 MPa) and group 5 (ECYL) (17.39 ±â€¯2.26) showed comparable result to that of CHX (p > 0.05). CONCLUSIONS: Bond strength of RMGIC bonded to CHX disinfected caries affected dentin was highest among study groups. Use of MB showed lowest shear bond strength outcomes. Moreover, application of ECYL and curcumin with LED showed bond strengths comparable to CHX control.

Influence of electronic nicotine delivery systems (ENDS) in comparison to conventional cigarette on color stability of dental restorative materials.

OBJECTIVE: The use of Electronic Nicotine Delivery Systems (ENDS) is increasing rapidly. However, its discoloring effect on dental restorations is not known. This study aimed to evaluate the effect of ENDS aerosol when compared to conventional cigarette smoke (CS) on the color stability of dental ceramic (DC) and resin composite (RC). METHODS: This research project was conducted from November 2018 to May 2019. In this study 30 discs each for DC and RC materials were fabricated to be equally divided into groups of exposure to CS, ENDS aerosol and storage in distilled water (No smoke; NS) respectively (n=10). Specimens were exposed for a total of 7 days, with a rate of 10 cycles per day, each cycle represented 10 puffs. The color change was assessed using the CIELAB color space, by calculating ΔE. Data was analysed using ANOVA and multiple comparisons test. RESULTS: Ceramic specimens in CS (2.422 ± 0.771) and ENDS (2.396 ± 0.396) groups showed comparable ΔE (color change) (p=0.992). Similarly, composite specimens in CS (42.871 ± 2.442) and ENDS (46.866 ± 3.64) groups showed comparable ΔE (p>0.05). NS specimens in both composite and ceramic samples showed lower ΔE than CS and ENDS specimens respectively. CONCLUSIONS: Aerosol from Electronic nicotine delivery systems (ENDS) showed similar discoloration levels as cigarette smoking (CS). The level of discoloration for ceramic samples for both ENDS and CS was below clinically perceptible levels (Mean ΔE < 2.5). Discoloration of composite resin due to CS and ENDS was visually perceptible (Mean ΔE > 4.0).

Clinical efficacy of photodynamic therapy as an adjunct to mechanical debridement in the treatment of per-implantitis with abscess.

AIM: The aim of the present clinical trial was to evaluate the efficacy of photodynamic therapy (PDT) as an adjunct to mechanical debridement (MD) in the treatment of severe peri-implantitis (PI) with abscess. MATERIALS AND METHODS: Selected individuals with severe PI were divided into two groups: Group A: received methylene blue mediated (PDT) using diode laser as an adjunct to MD, whereas, Group B received thrice daily application of 500 mg amoxicillin and 400 mg metronidazole with adjunctive MD. Peri-implant plaque scores (PS), probing depth (PD), bleeding on probing (BOP) and clinical attachment loss (CAL) were reported. Microbial counts of Porphyromonas gingivalis, Treponema denticola and Tannerella forsythia were analyzed using polymerase chain reaction. The assessment of pain was done with the help of numeric pain rating scale (NPRS). All assessments were done at baseline and repeated at 6 and 12 months, respectively. RESULTS: A total of 40 individuals completed the clinical trial. Both Group A and Group B comprised of 20 patients respectively. A significant improvement was observed in BOP in Group A at 12 months compared to Group B. No statistically significant changes were seen for NPRS scores between both groups (p > 0.05). Statistically significant differences were observed in values for P. gingivalis, T. denticola and T. forsythia at 6 months follow-up period in comparison to baseline for both Group A and Group B (p < 0.05). Whereas, the values observed at 6 months follow-up period for Porphyromonas gingivalis also reported a statistically significant difference in between the groups (p < 0.05). CONCLUSION: PDT was equally effective in reducing severe peri-implant symptoms compared to antimicrobial therapy as an adjunct to mechanical debridement.

Efficacy of chlorhexidine, Er Cr YSGG laser and photodynamic therapy on the adhesive bond integrity of caries affected dentin. An in-vitro study.

AIM: To evaluate the adhesive bond integrity (shear bond strength-SBS) of composite resin bonded to carious dentin using chlorhexidine gluconate (CHX), Er,Cr:YSGG laser (ECYL) and photodynamic therapy (PDT). MATERIAL AND METHODS: Thirty carious and ten non-carious mandibular teeth were collected through non-traumatic extraction. All samples were embedded in polyvinyl cross-sections to the cemento-enamel junction. The preparation of caries-affected dentin was performed by grinding the specimens using silicon carbide discs. All specimens were randomly allocated in to four groups (n = 10). Group 1, non-affected dentin with no disinfection; Group 2, caries affected dentin treated with 2% CHX; Group 3, affected dentin disinfected with PDT [100 mg/L methylene blue solution (MBS) and Diode laser]; Group 4, affected dentin treated with ECYL. Self-etch adhesive was smeared on all specimens for 10 s and photopolymerized for 10 s. All specimens were placed in an incubator with humid environment for 24 h at 37 °C followed by positioning in universal testing machine for SBS testing. Failure mode examination of debonded samples was performed by a stereomicroscope. Analysis of variance (ANOVA) was used for inter group comparison through mean and standard deviation of each group. For multiple group comparison Tukey HSD was employed. Level of significance was established at p < 0.05. RESULTS: The highest SBS value was observed in group 1 (24.98 ± 1.59 MPa). Whereas, the lowest bond strength was displayed by group 3 (14.22 ± 1.40 MPa) specimens. Lased dentin in group 4 (15.89 ± 3.22 MPa) exhibited SBS values comparable to group 3 (14.22 ± 1.40 MPa). Group 2 (CHX-18.25 ± 1.29 MPa) exhibited statistically significant difference compared to all experimental groups (p < 0.05). CONCLUSIONS: Adhesive bond strength of disinfected carious dentin was higher with CHX treatment as compared to Photodynamic therapy and Er,Cr: YSGG laser treatment. Carious dentin showed lower bond strength to composite resin as compared to non-carious dentin.

Influence of experimental staining on the color stability of indirect computer-aided design/computer-aided manufacturing dental provisional materials.

OBJECTIVE: This study presents a comparative analysis of the color stability of computer-aided design/computer-aided manufacturing (CAD/CAM)-fabricated provisional restorations with those of conventional restorations. MATERIALS AND METHODS: Three different provisional restorative materials (Systemp C&B, 3M Protemp 4, and Telio CAD) were inspected for their color stability using four solutions (Pepsi, coffee, tea, and distilled water). All samples used were fabricated using A1 shade by following the manufacturer's instructions. Color assessment was performed using CIELAB system and a colorimeter. After baseline color measurement, color assessments were done weekly after immersion in specified solutions. Triplicate readings were taken for every sample and the mean value of the color coordinates (L*), (a*), and (b*) were recorded at baseline, week 1, week 2, week 3, and week 4. The data within different groups were compared statistically using analysis of variance (α = 0.05). RESULTS: Overall, the highest color stability was found in CAD/CAM material, followed by Protemp and SystempC&B. It was also observed that the maximum color variation was observed in case of coffee, followed by tea and Pepsi. CONCLUSIONS: CAD/CAM provisional material (Telio CAD) showed better color stability compared to conventional materials (Protemp 3M ESPE and SystempC&B Ivoclar Vivadent). CAD/CAM provisional materials are recommended for long-term temporization procedures. This is attributed to the prepolymerization, higher monomer conversion, and minimal preparation errors in CAD/CAM materials.

Sealing Ability of Esthetic Post and Core Systems.

AIM: To review the literature on the sealing ability of esthetic post systems with different cementation techniques. BACKGROUND: An important factor for successful root canal treatment is the development of a coronal seal to the treated root canal system. Review result: The current literature describes promising results using fiber posts with a dual-cure, self-etch resin cement system. However, none of the published results describe a post system or cementation technique that achieved a homogeneous and tight coronal seal. CONCLUSION: Fiber post systems appear to be favorable alternatives to metallic or ceramic post systems. Furthermore, dual-cure, self-etch resin cement systems represent superior alternatives to other cement systems. CLINICAL SIGNIFICANCE: The clinician should be aware of the differences between various post systems and different cement systems to select and apply the most appropriate post and cement in each clinical situation.