Periodontal, Microbiological, and Proinflammatory Cytokines Levels in Fixed Orthodontics Patients Treated with Photodynamic Therapy Adjunct to Full Mouth Scaling.

Objective: To assess the efficiency of photodynamic therapy (PDT) adjunct to full mouth scaling (FMS) in improving periodontal, microbiological, and proinflammatory cytokines levels in patients undergoing fixed orthodontics treatment (FOT). Materials and methods: The study recruited 60 teenage patients who were undergoing FOT. All the patients were arbitrarily divided into two groups: Group 1, FMS +PDT and Group 2, FMS alone. Plaque scores (PS), bleeding on probing (BOP), and probing depth (PD) were assessed. Levels of biomarkers interleukin (IL)-6 and tumor necrosis factor-alpha (TNF-α) using enzyme-linked immunosorbent assay were evaluated. Samples were collected from gingival plaque for estimation of Prevotella intermedia and Porphyromonas gingivalis load. All measurements were completed at three intervals baseline, 4th week, and 8th week. Post Hoc corrections and intergroup comparisons were examined using Student's t-test and Bonferroni correction. To find differences between repeated follow-ups, analysis of variance (ANOVA) multiple rank tests were used. Results: At baseline, all the gingival parameters displayed comparable outcomes between patients of Group 1 and Group 2 (p > 0.05). However, at 4 and 8 weeks of follow-up, PS and BOP among tested groups exhibited significantly lower values than baseline (p < 0.001). At 8 weeks, there was a significant difference in PS between the two groups tested. Moreover, at 4 and 8 weeks, BOP revealed a significant difference between the groups. PD remains comparable with baseline at follow-up visits (p > 0.05). A significant decrease in IL-6 and TNF-α levels was observed in both investigated groups at 4 and 8 weeks of baseline. Moreover, it was identified that P. intermedia and P. gingivalis were reduced significantly at 4 weeks. Moreover, a significant difference existed between both Group 1 and Group 2 at 4 and 8 weeks of recall visit (p < 0.05). Conclusions: The use of photodynamic treatment adjuvant to FMS aids in improving periodontal parameters and cytokines levels.

Disinfection of polyvinyl siloxane impression material using ozone gas, 0.1% riboflavin, glutaraldehyde, and microwave irradiation and their effect on physical properties.

AIM: To assess the antimicrobial effect of ozone gas (OG) 0.1% riboflavin (RF), glutaraldehyde (GaH), and microwave irradiation (MI) on Polyvinyl siloxane impression material formerly colonized with E. coli, P. Aeruginosa, E. faecalis, and S.aureus and their effect on the physical properties MATERIAL AND METHODS: One hundred disk-shaped specimens (diameter 10 mm and thickness 3 mm) were developed by using polyvinylsiloxane impression material and inoculated by the American Type Culture Collection (ATCC) of E. coli, P. aeruginosa, E. faecalis, and S.aureus in an in-vitro setup. The samples were arbitrarily isolated into five groups and subjected for 3 min to the designated disinfection modality. Group 1 Control, group 2: GaH, group 3: 0.1% RF, group 4: MI, and group 5 OG. Following decontamination, the physical properties (contact angle, strain-in-compression, and tear strength) of impression materials were evaluated. Statistical analysis for CFU/mL (log10) for exposed E. coli, P. aeruginosa, E. faecalis, and S.aureus was performed by using analysis of variance (ANOVA) and Tukey's multiple comparison tests at a p-value of less than 0.05. RESULTS: The most effective antimicrobial efficacy for impression disinfection against all scrutinized microbial colonies were displayed by group 5 OG and the lowest disinfection effectiveness was unveiled by the control group with no treatment. The intragroup comparison revealed that impression disinfection with GaH, MI, and ozone corroborated analogous antimicrobial efficacy(p > 0.05). The disinfecting capacity of the impression material with 0.1% RF was significantly less than MI, GaH, and OG (p < 0.05). CONCLUSION: Disinfection of polyvinyl siloxane impression material with ozone gas, microwave irradiation, and glutaraldehyde demonstrated reasonable antimicrobial efficiencies against E. coli, P. aeruginosa, E. faecalis, and S.aureus with no detrimental effects on the physical properties of impression material. More studies are advocated to extrapolate the findings of the present study.

Levels of whole salivary advanced glycation end products and interleukin-17 and peri-implant clinical and radiographic status in patients with osteoporosis at 6-years' follow-up.

BACKGROUND: There are no studies that have assessed advanced glycation end products (AGEs) and interleukin 17A (IL-17A) levels in whole saliva (WS) of patients with dental implants. The aim was to compare levels of AGEs and IL-17A in WS and peri-implant clinical and radiographic status of patients with and without osteoporosis at 6-years' follow-up. METHODS: Osteoporotic (Group-1) and systemically healthy controls (Group-2) having undergone dental implant therapy at least 5 years ago were included. A questionnaire was used to collect information about age, gender, duration and treatment of osteoporosis, number and duration of implants in function, and frequencies of toothbrushing, flossing and hygiene visits. Modified bleeding and plaque indies (mBI and mPI), peri-implant probing depth (PD) and crestal bone loss (CBL) were recorded. WS was collected and levels of AGEs and IL-17A were determined using enzyme linked immunosorbent assay. Sample-size estimation was done and statistical analyses were doing using the independent t- and Wilcoxon rank-sum tests. Statistical significance was marked for P-values that were below 0.01. RESULTS: In patients with (n = 24) and without (n = 27) osteoporosis, implants were in function for 6.3 ± 0.27 and 6.6 ± 0.5 years, respectively. There was no significant difference in peri-implant mBI, PD, mPI and CBL in both groups. Levels of AGE in patients with (119.6 ± 26.5 µg/ml) and without (91.5 ± 14.6 µg/ml) osteoporosis were comparable. Levels of whole salivary IL-17A in patients without and with osteoporosis were 4.6 ± 0.3 and 5.1 ± 0.8 pg/ml, respectively. Flossing of full mouth interproximal spaces once and twice daily toothbrushing daily was reported by 100% patients with osteoporosis. Among patients with osteoporosis 75% and 25% individuals were receiving professional dental prophylaxis every 4 and 6 months, respectively. CONCLUSION: Within the limitations of the present study osteoporotic patients are not at an increased risk of peri-implant diseases and can demonstrate salivary AGE and IL-17A levels comparable to non-osteoporotic individuals as long as oral hygiene is stringently maintained.

Efficacy of chemical and photoactivated disinfectants against Candida Albicans and assessment of hardness, roughness, and mass loss of acrylic denture base resin.

AIM: The present study aimed to assess the antimicrobial efficacy of hematoporphyrin derivative, sodium hypochlorite (NaOCl), glutaraldehyde (GaH), and a chlorhexidine (CHX) on mass loss (ML), microhardness, and surface roughness (Ra) of acrylic denture base colonized with C. Albicans. MATERIAL AND METHODS: A total of 40 heat cure acrylic resin dentures were fabricated and inoculated by the American Type Culture Collection (ATCC) of C. Albicans in an in-vitro situation. Specimens were divided into four groups (n = 10) based on the method of disinfection. Hematoporphyrin derivatives, 1% NaOCl, 2% GaH, and 4% CHX.The pre and post candida (CFU/ml) counts were recorded before and after immersion. ML, microhardness, and Ra of acrylic denture were also assessed. Statistical analysis was executed for CFU/mL (log10) for exposed C. Albicans by two-way ANOVA and Tukey's multiple tests (p > 0.05). For normality of the data, Dunnet's Simultaneous test was performed. RESULTS: In terms of candida strain analysis, pretreatment to posttreatment comparisons revealed a reduction in mean Candida count in all groups (p < 0.05). The highest ML value after post candida disinfection of acrylic denture was observed in 2% GaH (1.587 ± 0.25) treated specimens. The least microhardness value was found in group 1 when treated with hematoporphyrin (0.97 ± 0.22 VHN) which was significantly different from other groups (p < 0.05). Group 1 surface treated with hematoporphyrin derivate (1.84 ± 0.22 µm) showed the highest Ra values (p < 0.05). CONCLUSION: Acrylic denture base resin colonized with C. Albicans when treated with a chemical disinfectant of 4% chlorhexidine displayed the highest antimicrobial efficacy with reduced mass loss, less surface roughness, and maximum denture hardness.

Water Sorption, Water Solubility, and Rheological Properties of Resin-Based Dental Composites Incorporating Immobilizable Eugenol-Derivative Monomer.

The present study aimed to evaluate the properties of new dental formulations incorporating a new polymerizable-derivative of eugenol (EgGMA). The experimental composites were prepared (by weight) with 35% resin-based matrix (1:1, bisphenol A-glycidyl methacrylate/triethylene glycol dimethacrylate) and 65% reinforcing materials (4:3, hydroxyapatite/zirconium oxide). A portion of 0.0, 2.5, and 5.0% of the resins with respect to the total composite was replaced by EgGMA monomer to obtain TBEg0, TBEg2.5, and TBEg5, respectively. The complex viscosity (at 25 and 37 °C), degree of conversion (DC), and water sorption (WSP) and water solubility (WSL) (3 cycles of sorption-desorption process) were investigated. Data were statistically analyzed using one-way and Tukey post-hoc tests. The results revealed a viscosity reduction with shear-thinning behavior as the EgGMA amount and temperature increased. The average complex viscosities at a lower frequency (ω = 1.0 rad/s) and at 25 °C were 234.7 ± 13.4, 86.4 ± 16.5, and 57.3 ± 17.1 (kPa·s) for TBEg0, TBEg2.5, and TBEg5, respectively. The inclusion of EgGMA led to a lower DC and WSP but higher WSL, compared to those of the reference (TBEg0). However, no significant differences between TBEg2.5 and control were detected (p > 0.05). Therefore, the incorporation of EgGMA in a low quantity, e.g., up to 8.45 mol% of resins, within the matrix may enhance the composite's performance, including handling and solubility properties without any apparent effect on DC and water sorption, making it a promising monomeric biomaterial for various applications including restorative dentistry.

Eugenyl-2-Hydroxypropyl Methacrylate-Incorporated Experimental Dental Composite: Degree of Polymerization and In Vitro Cytotoxicity Evaluation.

The aim of this study was to evaluate the properties of new dental formulations containing eugenyl-2-hydroxypropyl methacrylate (EgGMA) monomer, as restorative dental material, in terms of their degree of photopolymerization and cytotoxicity. The target model composites (TBEg0, TBEg2.5, and TBEg5) were prepared by mixing 35% organic matrix (TEGDMA/BisGMA (50/50 wt%) of which 0, 2.5, and 5 wt%, respectively, were replaced with EgGMA monomer) with 65% filler (silanized hydroxyapatite (HA)/zinc oxide (ZnO2), 4:3 by weight). The vinylic double-bond conversion (DC) after light-curing was studied using Fourier transform infrared technique whereas cell viability was in vitro tested using primary human gingival fibroblasts cells over 7 days by means of AlamarBlue colorimetric assay. The obtained data were statistically analyzed using ANOVA and Tukey post-hoc tests. The results revealed no significant difference in DC between TBEg2.5 (66.49%) and control (TBEg0; 68.74%), whereas both differ significantly with TBEg5, likely due to the inhibitory effect of eugenol moiety at high concentration. The cell viability test indicated that all the composites are biocompatible. No significant difference was counted between TBEg2.5 and TBEg5, however, both differed significantly from the control (TBEg0). Thus, even though its apparent negative effect on polymerization, EgGMA is potentially safer than bisphenol-derived monomers. Such potential properties may encourage further investigations on term of EgGMA amount optimization, compatibility with other dental resins, and antimicrobial activity.

Role of Probiotics for the Treatment of Peri-Implant Mucositis in Patients With and Without Type 2 Diabetes Mellitus.

This study hypothesized that probiotic therapy (PT) does not offer additional benefits to mechanical debridement (MD) for the treatment of diabetic subjects with peri-implant mucositis (PM). This study compared the influence of PT as an adjunct to MD for the treatment of PM in type 2 diabetic and nondiabetic patients over a 12-month follow-up period. Patients with and without type 2 diabetes were included. PM patients were categorized into 2 groups based on the treatment procedure: (1) nonsurgical + PT and (2) nonsurgical MD alone. Demographics and education statuses were recorded. Gingival index (GI) and plaque index (PI), crestal bone loss (CBL), and probing depth (PD) were measured at baseline and after 6 and 12 months. Significant differences were detected with P < .01. The hemoglobin A1c level was significantly higher in patients with diabetes at all time durations than in patients without type 2 diabetes (P < .001). Baseline GI, PI, PD, and CBL were comparable in all groups. In patients with type 2 diabetes, there was no difference in PI, GI, PD, and CBL at 6- and 12-month follow-up. In patients without type 2 diabetes, there was a significant reduction in PI (P < .01), GI (P < .01), and PD (P < .01) at 6-month and 1-year follow-up as compared with baseline. In patients without type 2 diabetes, MD with or without adjunct PT reduced soft-tissue inflammatory parameters in patients with PM.

Efficacy of Antibiotic Versus Probiotics As Adjuncts to Mechanical Debridement for the Treatment of Peri-Implant Mucositis.

The objective was to compare the efficiency of probiotic therapy (PT) vs antibiotic therapy (AT) as adjuvants to nonsurgical-mechanical debridement (NSMD) for the treatment of peri-implant mucositis (Pi-M). Volunteers with Pi-M were encompassed. Therapeutically, patients were randomly divided into 3 groups: (a) Group 1: NSMD + PT; (b) Group 2: NSMD + AT; and (c) Group 3: NSMD alone. Peri-implant plaque index (PI), bleeding on probing (BOP), probing depth (PD), and crestal bone loss (CBL) were recorded at baseline and at 3 and 6 months follow-up. P < .05 was selected as the indicator of statistical significance. Forty-two male individuals (14, 14, and 14 in Groups 1, 2, and 3, respectively) were included. At 3 and 6 months of follow-up, PI (P < .01), BOP (P < .01), and PD (P < .01) were higher in Group 2 than Group 1. At 3 months of follow-up, PI (P < .01), BOP (P < .01), and PD (P < .01) were higher in Group 3 than Group 2. At 6 months of follow-up, PI, BOP, and PD were comparable in Groups 2 and 3. In Group 3, PI, BOP, and PD were comparable with the respective baseline values at 6 months of follow-up. The CBL in all groups remained unchanged up to 6 months of follow-up. The NSMD with adjuvant PT is more effective than adjunct AT for the treatment of Pi-M for up to 3 months.

Relationship between buccal alveolar bone thickness and crown-to-root dimensions around mandibular first and second molars: A cone-beam-computed tomography-based study.

BACKGROUND: Assessment of buccal alveolar bone thickness (ABT) and crown-to-root dimensions are essential in implant density; therefore, three-dimensional evaluation of these parameters provides a superior visualization than conventional radiographs. OBJECTIVE: The present cross-sectional cohort study aims to investigate the relationship between buccal ABT and crown-to-root dimensions around the mandibular first and second molars using cone-beam-computed tomography (CBCT). METHODS: Initially, CBCT-based scans from 271 individuals were assessed. Based on the inclusion and exclusion criteria, 171 CBCT-based scans were excluded. In total, 100 CBCT-scans were included in the present investigation and processed for data extraction. On the mandibular first and second molars, the mesial and distal root lengths and mesiodistal diameter of the crowns were measured. The pulpal floor served as a reference point for assessment of root length. The buccal ABT was measured at the coronal, middle and apical one-third of the root. Statistical analysis was performed and the level of significance was set at P< 0.01. One-hundred CBCT-scans from 294 mandibular teeth (137 first molars and 157 second molars) were included. One hundred and eighty-nine and 105 teeth were from males and females, respectively. RESULTS: The normality plot showed a normal data distribution. The mesiodistal crown width showed a weak yet significant correlation with mesial root length (r= 0.137), bone thickness at mesial apical third (r= 0.180), distal apical (r= 0.157) and distal coronal third (r= 0.161). Bone thickness at mesial, middle and apical third correlated significantly with one other (r= 0.786). CONCLUSION: There is a direct correlation between the buccal ABT and tooth dimensions around the mandibular first and second molars.

Efficacy of Nonsurgical Mechanical Debridement With and Without Adjunct Low-Level Laser Therapy in the Treatment of Peri-Implantitis: A Randomized Controlled Trial.

We hypothesized that in the long term (6-month follow-up), nonsurgical mechanical debridement (NSMD) with adjunct low-level laser therapy (LLLT) is more effective for the treatment of peri-implantitis than NSMD alone. The aim of the present 6-month follow-up convenience-sample cohort study was to assess the efficacy of LLLT as an adjunct to NSMD in the treatment of peri-implantitis. A questionnaire was used to collect demographic information. Patients with peri-implantitis in the test and control groups underwent NSMD with and without adjunct LLLT, respectively. Randomization was done by tossing a coin. In the test group, the laser was applied perpendicular to the periodontal pocket for 20 seconds at a constant distance of 15 mm and with a continuous wavelength (3.41 J/cm2 delivery with a 1.76 cm2 spot and average output of 0.3 W). In both groups, peri-implant probing depth, bleeding upon probing, and crestal bone resorption were assessed at baseline and at the 3-month and 6-month follow-up. Group comparisons were performed, and P < .05 was considered statistically significant. Sixty-seven individuals with peri-implantitis were included. The mean age of participants who underwent NSMD with adjunct LLLT and NSMD alone was 46.5 ± 3.4 and 45.3 ± 1.1 years, respectively. At the 3- and 6-month follow-up, peri-implant (P < .05), bleeding upon probing (P < .05), and probing depth (P < .05) were significantly higher among patients who underwent NSMD alone compared with patients who underwent NSMD with adjunct LLLT. There was no significant difference in crestal bone resorption in all patients up to the 6-month follow-up. In the short term, NSMD with adjunct LLLT was a useful treatment protocol for the treatment of peri-implant soft-tissue inflammation.

Clinicoradiographic markers of peri-implantitis in cigarette-smokers and never-smokers with type 2 diabetes mellitus at 7-years follow-up.

BACKGROUND: It is hypothesized that in the long-term, (a) peri-implant inflammatory variables (plaque index [PI], bleeding on probing [BOP], probing depth (PD) and crestal bone loss [CBL]) are worse in cigarette-smokers (CS) and patients with type-2 diabetes mellitus (T2DM) than never-smokers (NS) without T2DM. The aim of the present 7-year follow-up clinical observational study was to assess the survival of dental implant in CS and NS with T2DM. METHODS: Study participants were divided into four groups based on glycemic status and self-reported cigarette-smoking habit: a) CS with T2DM; b) CS without T2DM; c) NS with T2DM; and d) NS without T2DM. Demographic information was collected using a questionnaire and hemoglobin A1c (HbA1c) levels were measured. Peri-implant PI, BOP, PD, and CBL were measured. Sample-size was estimated was statistical analysis was done using analysis of variance. P <0.01 was considered significant. RESULTS: In total, 101 male patients were included. There was no significant contrast in age among the groups. Every partaker in the study groups had one dental implant placed in posterior maxilla or mandible. The mean HbA1c levels were significantly higher among CS (P <0.01) and NS (P <0.01) with T2DM than individuals without T2DM. Peri-implant PI (P <0.01), PD (P <0.01), and CBL (P <0.01) were significantly higher among CS and NS with T2DM and CS without T2DM than NS without T2DM. Peri-implant BOP was significantly higher among CS and NS with T2DM than CS and NS without T2DM (P <0.01). CONCLUSIONS: Peri-implant inflammatory variables were worse among CS and NS with T2DM than NS without T2DM. A state of chronic hyperglycemia seems to be a stronger mediator of inflammation than cigarette smoking in patients with T2DM.

Self-rated peri-implant oral symptoms and clinicoradiographic characteristics in Narghile-smokers, cigarette-smokers, and nonsmokers with peri-implantitis.

BACKGROUND: The hypothesis is that self-rated peri-implant oral symptoms (OS) and clinical (plaque index [PI] and probing depth [PD]) and radiographic (crestal bone loss [CBL]) are higher in (cigarette-smokers [CS]) and (waterpipe-users) than (nonsmokers [NS]). The aim was to relate peri-implant self-perceived OS with clinico-radiographic parameters among CS, waterpipe-users, and NS. MATERIALS AND METHODS: This study was performed on self-reported CS, waterpipe-users, and NS with peri-implantitis. A questionnaire was used to record peri-implant self-perceived OS (pain in gums, bleeding gums, bad breath, and loose implant) and demographic data (age, sex, duration of smoking and waterpipe usage, duration of implants in function, duration since diagnosis of peri-implantitis). Clinico-radiographic parameters (CBL, PD, PI, and bleeding on probing [BOP]) were also measured; and compared with the self-perceived OS. Group comparisons were done for perceived OS and clinico-radiographic variables, and significant differences were deemed when P-values were under .05. RESULTS: One hundred male participants (35 CS, 33 waterpipe-users, and 32 NS) with peri-implantitis were included. Pain in gums (P < .05) and bad breath (P < .05) were more frequently perceived by CS and waterpipe-users than NS. There was no significant difference in perceived bleeding gums around the implant or loose implant among all groups. The CBL (P < .01), PI (P < .001), and PD (P < .01) were significantly high in CS and waterpipe-users than NS. NS (P < .05) had significantly higher BOP than waterpipe-users and CS. There was no significant difference in CBL, PI, PD, and BOP among waterpipe-users and CS. CONCLUSION: Tobacco-smokers present with worse peri-implant perceived OS and clinicoradiograhic parameters than nonsmokers with peri-implantitis.

Efficacy of mechanical debridement with and without adjunct antimicrobial photodynamic therapy in the treatment of peri-implantitis among moderate cigarette-smokers and waterpipe-users.

OBJECTIVE: The aim was to assess the efficacy of mechanical debridement (MD) with and without adjunct antimicrobial photodynamic therapy (aPDT) in the treatment of peri-implantitis among cigarette-smokers and waterpipe-users. MATERIALS AND METHODS: Patients diagnosed with peri-implantitis were included. Demographic data was collected using a questionnaire. Individuals in the test- and control-groups underwent MD with adjunct aPDT and MD alone, respectively. Peri-implant clinical (plaque-index [PI], bleeding on probing [BOP] and probing depth [PD]) and radiographic (crestal bone loss [CBL]) inflammatory parameters were measured at baseline and at 6- and 12-months follow-up. Sample-size estimation was performed, and statistical analysis was done. P-values <0.05 were considered statistically significant. RESULTS: Ninety-eight male patients with peri-implantitis (34 cigarette-smokers, 32 waterpipe-users and 32 never-smokers) were included. At baseline, there was no difference in the peri-implant PI, PD and CBL in all groups; and BOP levels were significantly high among never-smokers (n = 16) (P < 0.01) than cigarette-smokers (n = 17) and waterpipe-users (n = 16). There was no difference in PI, BOP, PD and CBL among cigarette-smokers (n = 17) and waterpipe-users (n = 16) that underwent MD alone at 3- and 6-months' follow-up compared with baseline. Compared with baseline, PI (P < 0.05) and PD (P < 0.05) were significantly lower among cigarette-smokers (n = 17) and waterpipe-users (n = 16) that underwent MD + aPDT at 3-months' follow-up. At 6-months' follow-up, PI, BOP and PD were significantly lower in never-smokers (n = 16) than their respective baseline and 3-months' follow up outcomes. CONCLUSION: MD with adjunct aPDT is effective for the treatment of peri-implantitis. Routine oral hygiene maintenance plays a role in the overall success of MD with or without aPDT in patients with peri-implantitis.

Effect of universal adhesives on microtensile bond strength to hybrid ceramic.

BACKGROUND: The aim of this study was to evaluate the effect of universal adhesives (UA) and silane on the microtensile bond strength (µTBS) of resin cement to a hybrid ceramic Vita Enamic (VE). METHODS: VE specimens were acid etched using hydrofluoric acid (HF) and were assigned to three groups (n = 10) based on the applied bonding technique. In group 1 (S), a silane-based primer was used as a surface treatment prior to the application of a resin cement (Variolink Esthetic DC). In group 2, a silane-containing UA, Clearfil Universal Bond (CUB) was used for the surface treatment, and in group 3, A silane-free UA, Tetric N-Bond Universal (TNU) was used for surface treatment. Resin cement build-ups were prepared. The bonded specimens were sectioned into resin-ceramic beams. Half of the beams of each group were stored for 24 h at 37 °C and the other half were subjected to a thermo-cycling aging. The microtensile bond strength (µTBS) was measured at a crosshead speed of 0.5 mm/min. Failure modes were assessed accordingly. Data were analyzed using a) two-way analysis of variance ANOVA followed by one-way ANOVA and Tukey tests between groups and b) independent t-test to detect differences (α = 0.05) for each group. The surface topographies of the ceramic surface were evaluated using scanning electron microscopy. RESULTS: The results showed that silane-based primer (S) application resulted in significantly higher (p < 0.05) µTBS values after 24 h and after thermocycling compared to both silane-containing UA (CUB) and silane-free UA (TNU). The µTBS values of all groups were significantly reduced after thermocycling. No statistically significant difference was observed between the µTBS of CUB and TNU after 24 h. However, TNU showed significantly higher µTBS after thermocycling. Different failure modes were observed, and adhesive failure was the most common in all groups. Marked surface topographic changes were observed following HF etching. CONCLUSION: It is concluded that, the UAs tested cannot be recommended as substitutes to the silanization of Hybrid ceramic.