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This article investigated the effects of airborne-particle abrasion and nanosilica (nano-Si) infiltration treatment on the surface characteristics of dental zirconia. A total of 15 unsintered zirconia ceramic green bodies (10 × 10 × 3 mm) were divided into three groups (n = 5): Group C, no treatment after sintering; Group S, airborne-particle abrasion with 50-µm aluminum oxide particles after sintering; and Group N, infiltration of nano-Si followed by sintering and hydrofluoric acid (HF) etching. The zirconia disks' surface roughness was analyzed by atomic force microscopy (AFM). The surface morphology of the specimens was analyzed using scanning electron microscopy (SEM), and the chemical composition was analyzed by energy-dispersive x-ray (EDX). Data were statistically analyzed by Kruskal-Wallis test (P < .05). Zirconia surface treatments by infiltration of nano-Si, sintering, and HF etching showed multiple changes in the surface features. The surface roughness of Groups C, S, and N were 0.88 ± 0.07 µm, 1.26 ± 0.10 µm, and 1.69 ± 0.15 µm, respectively. The surface roughness of Group N was significantly higher than that of Groups C and S (P < .05). EDX analysis showed peaks that corresponded to silica (Si) after infiltration with colloidal Si that disappeared following acid etching. Infiltrating nano-Si increases the surface roughness of zirconia. The formation of retentive nanopores on the surface potentially improves the zirconia-resin cement bonding strengths. [ABSTRACT FROM AUTHOR]

Objectives: The objective was to evaluate the polymerization efficiency of different bulk-fill resin-based composites cured by monowave and polywave light-curing units, by assessment of the degree of conversion and Vickers microhardness at different depths. Method and materials: Two commercially available bulk-fill resin-based composites were used: Filtek One Bulk Fill Restorative (3M ESPE) and Tetric N-Ceram Bulk Fill (Ivoclar Vivadent). The light-curing units utilized were two LED light-curing units: a monowave LED light-curing unit (BlueLEX LD-105, Monitex) and a polywave LED light-curing unit (Twin Wave GT-2000, Monitex). For each test, 20 cylindrical specimens (4 mm diameter, 4 mm thickness) were prepared from each bulk-fill resin-based composite using a split Teflon mold. Ten specimens were light-cured by the monowave light-curing unit and the other ten were light-cured by the polywave light-curing unit according to the manufacturer's recommendations. Attenuated total reflectance-Fourier transform infrared spectroscopy (ATRFTIR) was used to assess the degree of conversion, and a Vickers microhardness tester was used to assess Vickers microhardness. Statistical analysis was performed using three-way ANOVA and Tukey post-hoc tests (P < .05). Results: The degree of conversion and Vickers microhardness in bulk-fill resin-based composites containing only camphorquinone as photoinitiator were similar when cured with either monowave or polywave light-curing units. However, bulk-fill resin-based composites containing a combination of photoinitiators exhibited significantly higher degree of conversion and Vickers microhardness when cured with a polywave light-curing unit. Although all groups showed statistically significant differences between the top and bottom surfaces regarding degree of conversion and Vickers microhardness, all of them showed bottom/top ratios > 80% regarding degree of conversion and Vickers microhardness. Conclusion: The polywave light-curing unit enhanced the polymerization efficiency of bulk-fill resin-based composites especially when the latter contained a combination of photoinitiators, but does not prevent the use of a monowave light-curing unit. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the effect of sonic oscillation on penetration depth and marginal adaptation of resin-based fissure sealants. Method and materials: Thirty-six extracted human third molars were randomized into three groups: in the HF group, teeth were sealed with a filled-resin-based sealant (Helioseal F); in the Sonic-HF group, teeth were sealed with Helioseal F and subjected to sonic oscillation (Compothixo Device, 140 Hz vibration frequency and ± 150 µm amplitude) before curing; in the CO group, teeth were sealed with an unfilled-resin-based sealant (Clinpro). All teeth were thermocycled for 1,500 cycles at 5°C and 55°C, then sectioned buccolingually into four sections (mesial, two middle, and distal). Sections were evaluated under SEM for marginal adaptation and scored. For penetration depth, three independent measurements from each tooth were recorded under SEM, and data were subjected to statistical analysis. Results: The group subjected to sonic oscillation (Sonic HF) resulted in significantly superior penetration depth and marginal adaptation compared with the HF group, but with no significant difference compared with the CO group. Conclusions: Sonic activation of resin-based sealant increased penetration depth into fissures and marginal adaptation to the enamel wall without decreasing filler load or compromising sealant mechanical properties. [ABSTRACT FROM AUTHOR]

Purpose: To assess the handling properties and clinical function of a new class of material, a so-called mineral-organic bone adhesive (Tetranite; TN), which as yet has no precedent in orthopedic or oral and maxillofacial surgery, for clinically unstable implants placed in immediate extraction sockets and immediately temporized in the anterior maxilla. Materials and Methods: A cohort of up to 15 patients requiring between one and four immediate dental implants placed into maxillary extraction sockets from canine to canine were eligible for inclusion. Implants had to be unstable with an insertion torque of < 15 Ncm. Implants were then stabilized using TN, which was allowed to set before reassessing stability using both torque and resonance frequency measurements. Implant stability quotients (ISQs) taken after TN setting were compared to ISQs taken prior to its application, and the implants had to demonstrate resistance to a forward torque of 20 Ncm to be considered stable. ISQs were monitored at 1 week and 1, 3, 7, and 12 months postplacement. In addition, peri-implant tissue health was monitored, adverse events were recorded, and implant success was determined at 1 year postplacement. Results: Eleven patients received a total of 14 implants. Three out of the first six implants failed within 1 month (50%), and thus a protocol amendment was made to remove steps considered potentially destructive to the bonding process. As a result of these amendments, only one further failure was experienced for the next eight implants placed (12.5%). Mean ISQ data averaged for buccolingual and mesiodistal measurements demonstrated a baseline value before TN application of 59.1 Ncm (SD: ± 9.7; range: 40.5 to 73.0). After final setting of the TN, mean ISQ measured 71.9 Ncm (± 6.5; 56.0 to 80.0). At 3 months, just prior to restoration placement, mean ISQ measured 71.0 Ncm (± 6.6; 57.0 to 78.0). Thereafter, the mean ISQ continued to increase at both the 7- and 12-month follow-ups with scores of 78.9 (± 4.6; 72.0 to 84.5) and 80.3 (± 3.8; 74.5 to 85.0), respectively. The surviving 10 implants went on to be fully restored and remained in function beyond the end of the study period to yield a final success rate of 71.4%. Conclusions: The purpose of a first-in-human study is to demonstrate an extrapolation of preclinical data into the controlled human clinical arena. It is an opportunity to learn what does and does not translate well from experimental data. In that regard, the current pilot study can be deemed a complete success. The implant survival rate of 71.4%, while disappointing, should be considered in light of the protocol amendments identified, the user handling experience learned, and the opportunity to modify the material to better perform in the human patient, as all represent important lessons learned. The notable increase in ISQ sheds light on the nature by which the glue was substituted for bone to yield a stable implant by the end of the study period. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to investigate the bonding effectiveness of two HEMA/BPA-free universal adhesives (UAs) to flat dentin, to characterize their adhesive-dentin interfacial ultrastructure, and to measure their water sorption (Wsp), water solubility (Wsl), and hydrophobicity. Materials and Methods: The immediate and aged (50,000 thermocycles) microtensile bond strength (μTBS) to flat dentin of the HEMA/BPA-free UAs Healbond Max (HbMax; Elsodent) and Healbond MP (HbMP; Elsodent) as well as the reference adhesives OptiBond FL (Opti-FL; Kerr), Clearfil SE Bond 2 (C-SE2; Kuraray Noritake), and Scotchbond Universal (SBU; 3M Oral Care) was measured. The adhesive-dentin interfaces of HbMax and HbMP were characterized by TEM. Wsp and Wsl of all adhesive resins and of the primer/adhesive resin mixtures of HbMax, Opti-FL, and C-SE2 were measured. Hydrophobicity was determined by measuring the contact angle of water dropped on adhesive-treated dentin. Results: In terms of μTBS, HbMax and HbMP performed statistically similarly to Opti-FL and C-SE2, but outperformed SBU. Aging only significantly reduced the μTBS of SBU when applied in E&R bonding mode. TEM revealed typical E&R and SE hybrid-layer ultrastructures at dentin, while electron-lucent globules of unknown origin, differing in size and shape, were observed within the adhesive resin of HbMP and even more frequently in that of HbMax. Higher Wsp was measured for the primer/adhesive resin mixtures than for the adhesive resins. Opti-FL was more hydrophobic than all other adhesives tested. Conclusion: The HEMA/BPA-free UAs bonded durably to flat dentin with bond strengths comparable to those of the goldstandard E&R/SE adhesives and superior to that of the HEMA/BPA-containing 1-step UA. [ABSTRACT FROM AUTHOR]

This study investigated the effect of erbium, chromium: yttrium-scandium-gallium-garnet (Er,Cr:YSGG) laser conditioning on dentin bond strength and nanoleakage of different universal and self-etch adhesives. A total of 84 intact human third molar teeth were cut at the dentin level, and half of them were laser conditioned. The specimens were divided into three groups; two different universal resins and one self-etch adhesive resin were applied and composite resin restorations were created. For the microtensile bond strength (pTBS) test, 20 microspecimens were prepared from the laser and control group of each adhesive (n = 20) and tested with a universal device. For nanoleakage observation, 10 specimens were prepared from each group (n = 10) and stored in silver nitrate solution, and then the amount of nanoleakage was analyzed by field emission scanning electron microscopy (FESEM). Data were analyzed with two-way ANOVA, Tukey's honestly significant difference, and chi-square tests. The mean dentin bond strength of all adhesives in the laser groups was found to be statistically significantly lower than those of the control groups (P < .05). No difference was found between the mean bond strength of the adhesives in the laser and control groups (P > .05). Higher nanoleakage was observed in all adhesives in the laser groups compared to the control groups (P < .05). Irradiation of the dentin surface with Er,Cr:YSGG could adversely affect the piTBS and nanoleakage, likely by affecting the structure of the hybrid layer. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate the effect of 2% chlorhexidine (CHX) on an etch-and rinse adhesive to dentin. Caries-free molars were selected and processed to expose a flat dentin surface. The specimens were bonded with a composite resin by an etch-and-rinse adhesive, which was pretreated with 2% CHX for 0, 15, 30, 45, and 60 seconds. The microtensile bond strength (MTBS) was evaluated before and after thermocycling. No significant differences were observed between groups before thermocycling. The 60-second CHX-pretreated group showed a significantly greater MTBS than the control group after thermocycling. The 2% CHX pretreatment could improve the bonding strength of the etch-and-rinse adhesive and slow down the aging progress of the bonding interface. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the marginal leakage of three different types of bonding agents used with two posterior composites and a giomer, available commercially. Material and methods: Class II box-only cavities were prepared on 90 mandibular first molars with margins extending 1 mm beyond the cementoenamel junction. The samples were divided into nine groups based on three different bonding agents, two different composites, and a giomer. Cavities were restored per the manufacturer's description. Teeth were subjected to a thermocycling procedure (500Ã--, 5°C to 55°C) and dye penetration by immersing in a 2% methylene blue solution (Merck Specialties) for 24 hours. The marginal adaptation was evaluated as a continuous margin at the gingival level under a stereomicroscope. The results were analyzed using the Kruskal-Wallis and Mann-Whitney U tests. Results: The results of the groups with the total-etch technique showed no statistical difference between the nanohybrid Filtek Z250 XT (3M ESPE) and fine hybrid SwissTEC composite (Coltène\Whaledent AG). The groups with the self-etch technique showed no statistical difference when used with either of the two composites. The acid-etch technique showed better marginal adaptation than the self-etch technique. When the giomer (Beautifil II, Shofu) was used with the total-etch technique, it showed better adaptation than when used with the self-etch technique but overall showed more marginal leakage than the composites. Conclusion: The total-etch technique provided better marginal adaptation for the composites and giomer compared to the self-etch technique. Clinical significance: The demand for esthetic restorations continues to increase, and composite restorations are now considered the material of choice for Class II cavities. There are various concerns with composite restorations, one of them being good marginal adaptation to increase the life of the restoration. This study evaluated marginal leakage with the nanohybrid composite Filtek Z250 XT, fine hybrid composite SwissTEC, and a giomer when used with the total-etch technique and self-etch technique and reported satisfactory adaptation with the total-etch technique. [ABSTRACT FROM AUTHOR]

This article investigated the effects of airborne-particle abrasion and nanosilica (nano-Si) infiltration treatment on the surface characteristics of dental zirconia. A total of 15 unsintered zirconia ceramic green bodies (10 x 10 x 3 mm) were divided into three groups (n = 5): Group C, no treatment after sintering; Group S, airborne-particle abrasion with 50-p.m aluminum oxide particles after sintering; and Group N, infiltration of nano-Si followed by sintering and hydrofluoric acid (HF) etching. The zirconia disks' surface roughness was analyzed by atomic force microscopy (AFM). The surface morphology of the specimens was analyzed using scanning electron microscopy (SEM), and the chemical composition was analyzed by energy-dispersive x-ray (EDX). Data were statistically analyzed by the Kruskal-Wallis test (P < .05). Zirconia surface treatments by infiltration of nano-Si, sintering, and HF etching showed multiple changes in the surface features. The surface roughness of Groups C, S, and N were 0.88 ± 0.07 µm, 1.26 ± 0.10 µm, and 1.69 ± 0.15 µm, respectively. The surface roughness of Group N was significantly higher than that of Groups C and S (P < .05). EDX analysis showed peaks that corresponded to silica (Si) after infiltration with colloidal Si that disappeared following acid etching. Infiltrating nano-Si increases the surface roughness of zirconia. The formation of retentive nanopores on the surface potentially improves the zirconia-resin cement bonding strengths. [ABSTRACT FROM AUTHOR]

Two fractured maxillary central incisors were restored via the crown fragment reattachment technique with adhesive systems and composite resin material. A long-term successful outcome was achieved after 4 years of follow-up. The patient presented with fractured maxillary central incisors, and a comprehensive intraoral and radiographic examination revealed that both teeth had extended crown fractures with no pulpal exposure (Class II, Ellis and Davey). The tooth fragments were thoroughly cleaned and inspected before being repositioned. Both fragments were in excellent condition with almost no pieces missing. Therefore, the proposed treatment was fragment reattachment. After verifying the repositioning and adaptation of the fractured fragments, a flowable composite was used to perform the reattachment procedure under rubber dam isolation. With modern dental adhesives, the reattachment of tooth fragments in good condition is considered a more conservative option for restoring tooth morphology, esthetics, and function. Although one tooth showed signs of irreversible pulpitis and required root canal treatment 2 weeks after the restoration, the clinical and radiographic evaluations at the 4-year follow-up visits confirmed the success of the restorative treatment. The restorations showed good functional and esthetic outcomes after 4 years of follow-up. [ABSTRACT FROM AUTHOR]

Introduction: Sufficient information is not available regarding the comparative accuracy of digital and conventional impression techniques at different depths for the fabrication of endocrown restorations. Thus, this study aimed to compare the marginal (M) and internal (I) adaptation of endocrowns at different depths fabricated by the digital and conventional impression techniques. Materials and Methods: In this in vitro study, two endodontically treated molar teeth with 2‐ and 4‐mm cavity depths were used for the fabrication of endocrowns. Conventional and digital impressions were made from each tooth 17 times. A total of 68 zirconia endocrowns were fabricated and seated, and their I and M adaptation was assessed by the silicone replica technique. Data were statistically analyzed. Results: The M and I gaps at 2‐ and 4‐mm cavity depths were significantly smaller in the digital, than the conventional, impression technique (p < 0.05). Increasing the cavity depth significantly increased the M and I gaps only in the digital technique (p < 0.05). The largest gap in all groups was noted in the pulpal (P) region (p < 0.05). The smallest gap was found in the M and cervical (C) regions in the conventional groups with 2‐ and 4‐mm cavity depths, and the digital group with 4 mm cavity depth, and in the M region in the digital group with 2 mm cavity depth (p < 0.05). Conclusion: Unlike the conventional impression technique, the M and I adaptation decreased by an increase in cavity depth in the digital technique; nonetheless, the digital impression technique still showed higher M and I adaptation than the conventional technique. [ABSTRACT FROM AUTHOR]

In this multi-parameter study, the effect of diverse factors related to adhesive application on the activation of host-derived gelatinases was investigated by gelatin zymography, in-situ zymography, fluorogenic DQ-gelatin assay and micro-tensile bond-strength (μTBS) testing. Gelatin zymography disclosed the presence of gelatinases in phosphoric acid-etched dentin powder, while two gold-standard adhesives generated no measurable MMP activation. In-situ zymography revealed that the interfacial gelatinolytic activity from specimens treated with the two adhesives appeared similar as that of the EDTA negative control, indicating no detectable gelatinases were activated upon adhesive treatment. In solution, MMP-2/9 activity significantly decreased upon interaction with both adhesives (two-way linear mixed effects model [LMEM]: p < 0.05); gelatinases were almost completely deactivated upon 1-week incubation at 37 °C (general linear model: p < 0.05); light-curing adhesives increased temperature up to 55 °C, which appeared sufficient to dramatically decrease MMP-2/9 activity (two-way ANOVA: p < 0.05). Finally, challenging adhesive-dentin interfaces with highly concentrated MMP-9 (at a much higher concentration than present in saliva) for 1 m did not significantly affect μTBS (two-way LMEM: p > 0.05). Taken together, the two adhesives did not activate but rather inhibited the release and activation of dentinal gelatinases. [ABSTRACT FROM AUTHOR]

The aim of this systematic review was to assess the antimicrobial effectiveness of silver nanoparticles (AgNPs) incorporated to different orthodontic bonding systems. Additionally, the review investigated the impact of AgNPs on the bonding properties of these materials. The hypothesis posed that the addition of AgNPs would enhance the antimicrobial efficacy of orthodontic bonding systems while maintaining their bonding properties. The systematic review employed a PICO-based search strategy, targeting in vitro studies focusing on the integration of nano silver particles into orthodontic bonding systems with potential antimicrobial activity. The intervention involved the use of nano silver in orthodontic bonding systems, with a comparison to systems lacking nano silver. The primary outcomes assessed were antimicrobial activity and shear bond strength (SBS). The search process, conducted without publication date restrictions, yielded 551 potential articles: 34 from PubMed, 360 from PubMed Central, 42 from Embase, 54 from Scopus, and 61 from Web of Science. Ultimately, a qualitative synthesis was conducted on 13 papers. The PRISMA diagram, visually represented the search strategy, screening process, and inclusion criteria. The study protocol was registered in PROSPERO CRD42023487656 to enhance transparency and adherence to systematic review guidelines. Quality assessment of the included studies was performed using the Newcastle-Ottawa Scale, revealing that the 13 articles meeting the inclusion criteria demonstrated a high level of evidence. Seven studies were included in the meta-analysis regarding shear bond strength. In summary, the synthesized findings from these studies strongly underscore the promising potential of orthodontic materials modified with AgNPs. These materials exhibit effective resistance against cariogenic bacteria without compromising bonding properties below clinical acceptability. Such innovative materials hold significant implications for advancing oral health within the realm of orthodontics. [ABSTRACT FROM AUTHOR]

Background: Using infection control barriers (ICBs) on light curing units (LCUs) became mandatory to achieve proper infection control measures without jeopardizing the integrity of the restorations, especially at deeper layers. This study explored the effect of two ICBs on the irradiance of the LCU, as well as the degree of conversion (DC) and flexural strength (FS) of two types of bulk-fill composites. Water vapor permeability (WVP) of both barriers was also assessed to evaluate the capability of such barriers to prevent transmission of blood and saliva droplets and aerosols. Methods: Two bulk-fill composites (X-tra fil and Tetric N- ceram) and two ICBs (Pinnacle Cure sleeve and Sanita wrapping film) were used in this study. Light irradiance was recorded per experimental condition using spectroradiometer. For DC and FS, specimens of 4 mm thickness were prepared. Each specimen was composed of two separable upper and lower layers of thickness 2 mm. DC and FS were measured using Infra-red spectroscopy and three-point loading test respectively. WVP was investigated using the cup method. Means and standard deviations were calculated, and the data were statistically analyzed using factorial analysis of variance test (α = 0.05). Results: Light irradiance showed highest values using no ICBs and lowest values using Pinnacle curing sleeve. Both bulk-fill composites showed higher DC mean values without ICBs and when using Sanita wrapping film for both upper and lower layers of the specimens compared to Pinnacle curing sleeve. The upper layers of composite specimens showed higher DC compared to lower layers for all experimental conditions. Both ICBs had no adverse effect on FS of both composites' upper layers. Pinnacle sleeve significantly reduced FS of both composites' lower layers. X-tra fil showed higher DC and FS compared to Tetric N-Ceram for all experimental conditions. Regarding WVP; the wrapping film showed higher WVP compared to the curing sleeve. Conclusions: Sanita wrapping film can be used as a successful ICB, without jeopardizing the concept of bulk-fill composites. Pinnacle cure sleeve can be considered an effective ICB, however its influence on properties and serviceability of bulk-fill composites remains questionable. [ABSTRACT FROM AUTHOR]

Introduction: Non Carious Cervical Lesions (NCCLs) represent a prevalent dental condition characterised by the erosion of tooth structure at the cementoenamel junction without the involvement of dental caries. These lesions pose significant challenges due to their aesthetic impact, potential for dentinal hypersensitivity, plaque accumulation, pulpal complications and compromised structural integrity of the teeth. Tooth preparation traditionally uses diamond abrasive points and tungsten carbide burs for micromechanical adhesion. Newer methods, like ultrasonic tips, offer a more conservative approach, but limited research has compared their effects on bond strength, particularly in cervical cavity restorations with nanohybrid composites. Aim: To compare the surface roughness of cervical cavity preparations utilising diamond abrasive points and ultrasonic tips, and to evaluate the shear bond strength of restorations with composite resin. Materials and Methods: The present in-vitro comparative study was conducted in the Department of Conservative Dentistry and Endodontics, Guru Nanak Institute of Dental Sciences and Research, Panihati, Kolkata, West Bengal, India, from October 2023 to December 2023. The study included 52 freshly extracted maxillary 1st premolar teeth extracted for orthodontic reasons. These teeth were divided into two groups: Group-I (n=26) underwent surface preparation using a diamond abrasive point (No. 835-012, Piranha, SS White, USA), while Group-II (n=26) was prepared using an ultrasonic tip (Woodpecker G 20, Guilin Woodpecker, China). Teeth were cleaned, disinfected and stored in 0.1% thymol solution before being prepared with diamond abrasive points or ultrasonic tips, following which the specimens were restored using nanohybrid composite material (Solare X, GC Corporation, Japan). Surface roughness was assessed using a digital profilometer before the restoration, and the shear bond strength of repaired specimens was measured with a Universal Testing Machine. Statistical analysis was performed using GraphPad Prism, with independent samples t-tests applied to compare results between groups, and a significance level set at 5%. Results: Group-I exhibited greater surface roughness (6.33±2.18 μm) compared to Group-II (4.91±1.57 μm). Group-I also showed higher shear bond strength (62±13 MPa) than Group-II (59.3±19.9 MPa), though this variation was not statistically significant (p-value=0.56). Conclusion: Within the present study's limitations, diamond abrasive points created significantly greater surface roughness compared to ultrasonic tips. However, no statistically significant variations have been observed in shear bond strength among the two methods, suggesting that ultrasonic tips may be considered as an alternative to diamond abrasive points in clinical settings, avoiding their drawbacks while achieving adequate restoration retention. [ABSTRACT FROM AUTHOR]

Aims: This pilot study aimed to compare the marginal adaptation of composite resin at the tooth-restoration interface, before and after radiation. Subjects and Methods: Fifteen extracted premolars were divided into 2 experimental groups (based on the timing of irradiation) and 1 control group of 5 teeth each. In Group I (control group), teeth were restored but not exposed to radiation at any stage, Group II: teeth were irradiated before cavity preparation and restoration, and Group III: after cavity preparation and restoration employing selective etch technique, teeth were exposed to radiation. The samples were then sectioned buccolingually to analyze the extent of the marginal gap under scanning electron microscopy and compositional alteration of dental hard tissues by X-ray diffraction study. The data collected were analyzed statistically. Statistical Analysis Used: The statistical software used was IBM SPSS version 23 New York, USA, and analysis was done using two-way ANOVA followed by Turkey's post hoc test, this difference in the mean marginal gap between all three groups was nonsignificant (P ≥ 0.05). Results: In the control group (Group I), a minimum gap (4.203 µm ± 0.533) was observed at the tooth-restoration interface, indicating the highest level of adaptation as compared to Group II (5.816 µm ± 0.762) and Group III (4.862 µm ± 1.018). This suggests that radiation adversely affected the bonding between composite materials and both enamel and dentin, attributed to the alterations induced by radiotherapy in the chemical, physical, and morphological properties of both tooth structure and composite resin. Conclusions: Ionizing radiations adversely affect the bonding between enamel, dentin, and composite resin. Hence, restorative procedures should be performed before undergoing radiotherapy. [ABSTRACT FROM AUTHOR]

Background: It was aimed to investigate the effect of sandblasting and laser surface treatment on shear bond strength in composite restoration repair in vitro. Methods: A micro-hybrid composite (Filtek Z250, 3 M-ESPE, USA) was used to prepare 120 samples. The samples were subjected to a thermal cycle test 5,000 times between 5 and 55 0C, and they were randomly divided into 12 groups (n = 10). No surface treatment was performed in Groups 1 to 4, which were designed as control groups. The surfaces of the samples in Groups 5 to 8 were sandblasted with a Cojet device, and the surfaces of the samples in Groups 9 to 12 were applied Er, Cr: YSGG laser. After the sample surfaces were divided into groups with and without acid etching, universal adhesive was applied, and the repair process was performed using Filtek Z250 or nano-filled resin composite (Filtek Ultimate, 3 M-ESPE, USA). The thermal cycle test was repeated 5,000 times between 5 and 55 0C on all repaired samples. The repair shear bond strength of the samples was measured using a universal testing device (Shimadzu IG-IS, Kyoto, Japan). The fracture types were evaluated by optical microscopy and scanning electron microscopy (SEM). Statistical analyses of the findings were evaluated by the Kruskal Wallis test and Mann Whitney U test at 0.05 significance degree. Results: The highest mean shear bond strength values were obtained from the samples sandblasted with CoJet, followed by Er, Cr: YSGG laser, and the control group. It was determined that there was a significant difference between the mean shear bond strength values obtained from the control group and the other surface treatment groups (p < 0.05). In general, significantly higher mean shear bond strength values were obtained when the universal adhesive was applied in total-etch mode compared to the application in self-etch mode (p < 0.05). Additionally, it was determined that higher shear bond strength values were obtained with Filtek Ultimate compared to Filtek Z250 (p < 0.05). Conclusion: Within the limitations of this study, it can be concluded that the use of universal adhesive in total-etch mode, in addition to surface treatments on the resin composite surface in the repair protocol and the use of nano-filled resin composite as repair material can increase the mean shear bond values in repair. [ABSTRACT FROM AUTHOR]

Background: Radiotherapy is a treatment modality used for head and neck cancer patients. It has a negative influence on bonding strength of adhesives. Little information is available about the effect of radiotherapy on bonding strength of adhesives in primary teeth. Therefore, this in vitro study aimed to detect the best adhesive system and ideal time to apply restorations in primary irradiated teeth regarding adhesive shear bond strength. Methods: Dentin samples from primary teeth were randomly assigned to four groups based on restoration application time and radiation exposure, (G1: control, G2: preradiation, G3: 24 h postradiation, and G4: 6 months postradiation) with 20 samples per group. These groups were further divided into 2 subgroups according to the adhesive system used, with 10 samples per subgroup. (1) 3M™ Single Bond Universal Adhesive (SB), (2) 3M AdperSingle Bond 2 (AS). Samples were exposed to gamma radiation from a cobalt-60 machine. One shot of 60 Gy of radiation was delivered. Then samples were subjected to a shear bond strength test. The load was applied until failure and the maximum load was recorded. Numerical data are presented as mean and standard deviation values, then distributed according to Shapiro–Wilk test or Levene's test and analyzed via two-way ANOVA. The significance level was set at p < 0.05 for all tests. Statistical analysis was performed with R statistical analysis software version 4.4.1 for Windows (Team RC, R: A language and environment for statistical computing. R foundation for statistical computing, 2023). Results: Compared with the AS subgroup, the SB subgroup presented significantly greater values (p < 0.001). For SB, there was no significant difference among the G1 and G4 groups (p > 0.001). However, there was a significant difference between G1, G2, and G3 (p < 0.001, P = 0.025, P = 0.265 ns respectively), and G3 presented the lowest values. For AS, there was no significant difference between groups G1 and G4 (p = < 0.001). Compared with the other groups, G3 presented a significant difference (p = 0.265 ns) and the lowest results. Conclusion: Restorations performed 24 h after radiation had lower bond strength than those performed six months after radiation. Regardless of the adhesive system used, SB performed better than AS in terms of the shear bond strength. [ABSTRACT FROM AUTHOR]

Background: This study aims to evaluate the microtensile bond strength (µTBS) of different resin composite restorations bonded to mid-coronal dentin and proximal root dentin using light-cured, chemical-cured, and dual-cured adhesives immediately and after aging. Nanoleakage and degree of cure were also assessed. Methods: Eighty-four molars were divided into mid-coronal dentin and proximal root dentin. Each group was further subdivided into three subgroups based on the restorative systems used, which involved the utilization of light-cured, chemical-cured, and dual-cured adhesives. Half of the specimens underwent µTBS testing after 24 h, while the other half after aging. Representative specimens were analyzed for nanoleakage. The degree of cure of the tested adhesive systems was also assessed. Results: Aging showed a significant negative effect on µTBS results and led to increased nanoleakage (p < 0.001). Furthermore, in all subgroups, the µTBS values of proximal root dentin were lower compared to mid-coronal dentin, except in the aged subgroup for the system utilizing the dual-cured adhesive. The restorative systems with chemical and dual-cured adhesives demonstrated comparable bonding properties. However, the system with the light-cured adhesive exhibited the worst bonding properties after aging when bonded to proximal root dentin and cured at a large distance (p < 0.05). Conclusions: All tested restorative systems were negatively affected by aging, and the regional dentin had variable effects on the bonding properties. Clinicians should exercise caution when using the tested light-cured adhesive in areas where the curing distance exceeds 3 mm. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the in vitro influence of prior silane application on the microshear bond strength (μSBS) of Scotchbond Universal Plus to glass ceramic. Materials and Methods: Thirty blocks of lithium disilicate ceramic were etched with hydrofluoric acid for 20 s and distributed into Group 1 (no silane and no adhesive), Group 2 (adhesive), Group 3 (silane + adhesive). Three cylinders of resin cement were made on each ceramic block. Five blocks (n = 15 cylinders) were subjected to the μSBS test after 24 h, and the other five blocks (n = 15 cylinders) were tested after 6 months of water storage. Results: According to two‐way ANOVA, followed by Tukey's test, the means of μSBS (MPa), denoted by different letters, show significant differences (p < 0.05): after 24 h—Group 1 (31.7)B, Group 2 (43.3)A, and Group 3 (31.3)B; after 6 months—Group 1 (14.8)B, Group 2 (33.6)A, and Group 3 (30.3)A. After 6 months of storage, there was a significant decrease in μSBS for Groups 1 and 2, along with an increase in adhesive failures across all groups. Conclusions: Prior application of silane did not increase the μSBS between Scotchbond Universal Plus and ceramic, and there was degradation at the bond interface over time. Clinical Significance: Prior application of a silane agent is not necessary when using Scotchbond Universal Plus for bonding to glass ceramics. Regardless of the prior application of silane, there is degradation at the bond interface over time. [ABSTRACT FROM AUTHOR]

Objective: This clinical study aimed to evaluate the difference in the time of application phase, employing the conventional and modified direct orthodontic bonding method. Materials and Methods: Thirty patients who needed orthodontic therapy with fixed appliances were randomly divided into two equal groups (n = 15): the control and experimental group, according to the bonding method applied. A total of 600 metal brackets inch slot 0.022 (Mini Sprint®, Forestadent, Germany) were bonded to incisors, canines, and premolars using the light‐cured adhesive Transbond XT (3M Unitek, Monrovia, CA, USA). The failure rates of the brackets were evaluated within 12 months. The independent samples t‐test was applied. The Chi‐square test and Fisher exact test were used for statistical analysis. Results: The initial bonding time using the modified method was significantly shorter (3.27 min or 17.1% per patient) compared with the conventional bonding method (p < 0.001). Number of failed brackets between the two methods did not differ significantly (p = 0.226). Conclusion: The time of the application phase in initial bonding using the modified method (experimental group) was shorter than in control group. There was no statistically significant difference in the number of bond failures between the two methods. Clinical Significance: The modified application phase of direct orthodontic bracket placement shortens the total bonding time and facilitates the manual work of orthodontists. [ABSTRACT FROM AUTHOR]

Objectives: The objective of this review was to assess clinical trials that have examined the materials, design, and bonding of ceramic cantilevered resin‐bonded fixed dental prostheses (RBFDPs) as a potential option for replacing missing anterior teeth. The evaluation primarily focuses on the rate of restoration failure and clinical complications. Materials and Methods: A thorough search of databases including PubMed/MEDLINE, Scopus, and the Cochrane Library, was conducted. The most recent search was performed in October 2023. Clinical studies that compared ceramic cantilevered RBFDPs with double retainers or cantilevered RBFDPs using different ceramic materials or bonding systems were included. The outcome measures considered were restoration failure and complication rates. Results: Twelve studies met the eligibility criteria. The pooled data showed a statistically significant decrease in complication events when using cantilever designs compared with double retainer designs (p < 0.05); however, there were no differences found between the two designs in terms of restoration failure. The complication and failure rate of cantilever RBFDPs did not show a statistically significant difference with or without ceramic primer application before luting with phosphate monomer‐containing luting resin (p > 0.05). Conclusions: Ceramic cantilevered RBFDPs have lower complication rates compared with those with double retainers. The use of a ceramic primer prior to luting composite resin for ceramic cantilevered RBFDPs decreases the occurrence of complications and failures, although this effect was not statistically significant. Additional research is required to confirm these findings. Glass ceramic cantilever RBFDPs showed a decrease in success after 6 years, requiring ongoing monitoring, but both zirconia and glass‐infiltrated alumina cantilever RBFDPs have demonstrated durability with excellent long‐term success and survival rates for up to 10 and 15 years. Clinical Significance: Cantilever ceramic RBFDPs in the anterior region are a less invasive and valuable treatment option, providing good esthetic results. [ABSTRACT FROM AUTHOR]

This study evaluated the effects of two chlorophyll derivatives, sodium copper chlorophyllin (Cu‐Chl) and sodium iron chlorophyllin (Fe‐Chl), on the bond strength between a self‐curing luting agent (4‐META/MMA‐TBB resin) and dentin. Five aqueous primers containing 35% 2‐hydroxyethylmethacrylate with 0.007% Cu‐Chl, 0.07% Cu‐Chl, 0.007% Fe‐Chl, 0.07% Fe‐Chl, or neither Cu‐Chl nor Fe‐Chl (no‐Chl) were prepared. The extracted human dentin surfaces were etched with 10% phosphoric acid (10PA), primed, and bonded to a resin block using the 4‐META/MMA‐TBB resin. A conventional etching agent (10‐3) and 10PA without primer (PA/no‐primer) were used as controls. The microtensile bond strength was determined after 48 h. The arithmetic medians for 20 stick specimens were calculated and statistically analyzed using a nonparametric Steel‐Dwass test (α = 0.05). The maximum bond strength was achieved in the 0.007% Cu‐Chl group, followed by those in the 0.07% Cu‐Chl, 0.07% Fe‐Chl, 10‐3, 0.007% Fe‐Chl, no‐Chl, and PA/no‐primer groups. No significant difference was observed between 0.007% Fe‐Chl, 0.07% Fe‐Chl, and 10‐3. The bond strength to dentin etched with 10PA was influenced by the type and concentration of the chlorophyll derivatives applied. Cu‐Chl rather than Fe‐Chl should be useful as a component of surface treatment agents for bonding 4‐META/MMA‐TBB resin to dentin. [ABSTRACT FROM AUTHOR]

Challenges exist regarding the bonding efficiency of polyaryletherketone (PAEK), a high-performance thermoplastic, attributed to its chemical inertness and hydrophobic surface, hindering effective bonding with resin-matrix cement. This research explored the impact of handheld nonthermal plasma (HNP), under varying operational parameters, on PAEK surface wettability and changes in bonding performance with cement. Three types of disc-shaped PEAK specimens were prepared, with surface treatments categorized as grinding, airborne-particle abrasion (APB), and HNP. Surface wettability was analyzed using a contact angle analyzer (n = 10). Specimens were bonded with resin cement and subjected to artificial aging tests: distilled water bath (NA), thermocycling, and highly accelerated stress tests (n = 10 for each test). Shear bond strength (SBS) was measured, failure modes were analyzed, and statistical analyses were conducted. The HNP markedly improved PAEK surface wettability, achieving superhydrophilicity (P < 0.05). This effect intensified with extended operation times (30 or 60 s) and reduced elapsed times (<30 s). HNP-treated PAEK exhibited higher SBS than APB (P < 0.05) and maintained bonding durability after artificial aging, particularly in ketone-enriched variants. Failure analysis revealed predominantly adhesive failure under APB–NA treatment, mixture failures under HNP–NA treatment and postaging, but no cohesive failure. The HNP device benefits dental settings by transforming the PAEK surface into superhydrophilic properties, thereby improving PAEK–cement bonding. It significantly enhances bond durability within 30 s of operation and after a 30 s elapsed period. It is noteworthy that ketone-enriched PAEK demonstrates markedly improved bonding performance. [ABSTRACT FROM AUTHOR]

This is the first article in a three-part series that discusses joint orthodontic–restorative care for the adult patient. Part 1 presents an overview of the clinical presentations, challenges and strategies that may be employed to treat this complex patient group. CPD/Clinical Relevance: The reader should be able to describe a care pathway, with potential associated complications, for the provision of adult orthodontic–restorative treatment. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the fracture resistance of endodontically treated molars restored with ceramic indirect restorations with and without cervical margin relocation. A total of 120 extracted human maxillary molars were used after MOD cavities preparations with the mesial boxes located 2 mm below CEJ. Specimens were randomly assigned to six groups according to the margin location of each indirect restoration type (n = 20); crown without CMR, crown with CMR, endocrown without CMR, endocrown with CMR, onlay without CMR, and onlay with CMR. Mesial proximal boxes of the MOD cavities were elevated with composite resin in cervical margin relocation groups. Each group was further divided according to indirect restoration material (n = 10); CEREC Tessera and Celtra Press. The specimens were subjected to fracture resistance testing in a universal testing machine. Fracture analysis was performed using stereo and scanning electron microscopes. Data were analyzed by using 3-way ANOVA, 1-way ANOVA and the Tukey HSD tests (α = 0.05). The mean fracture resistance values ranged between 2136.57 and 950.47 N. Significantly higher values were detected among Celtra Press than Cerec Tessera in crown restorations. Unrestorable fracture patterns were seen through all study groups. Crown restorations represented the best restorative option in terms of fracture resistance. Cervical margin relocation adversely affected fracture resistance. However, the material of the indirect restorations had no significant impact on fracture resistance. [ABSTRACT FROM AUTHOR]

This study evaluated the effectiveness of atmospheric pressure plasma jet (APPJ) treatment on the surface characteristics and bond strength of zirconia and lithium disilicate ceramics for CAD-on restorations. A total of 70 cylindrical-shaped specimens of lithium disilicate and 70 disc-shaped specimens of Y-TZP zirconia were machined, thermally processed, surface-treated, and then resin-bonded. The specimens were grouped according to the following surface treatments: no surface treatment, sandblasting, plasma, sandblasting followed by plasma, sandblasting followed by universal adhesive, plasma followed by universal adhesive, and sandblasting and plasma treatment followed by universal adhesive. The treated surfaces were subjected to a wettability assessment via contact angle measurement and a topography assessment using scanning electron microscopy (SEM). The cemented assembly was subjected to shear bond strength testing with a universal testing machine, and the results were imported to SPSS 23.0 for statistical analysis. The results show that APPJ treatment induced a significantly low contact angle for both ceramics with no surface alteration upon scanning. Moreover, APPJ treatment produced a bonded assembly with a shear bond strength comparable to sandblasting. In conclusion, APPJ treatment should be considered an efficient surface treatment with a non-destructive nature that surpasses sandblasting with the provision of a high shear bond strength between CAD-on ceramics. [ABSTRACT FROM AUTHOR]

Background: Self-adhesive resin cements (SARCs) are widely used for fixed prostheses, but incomplete cleaning near the gingival margin can cause inflammation. However, the factors influencing cement properties and the biological response of gingival fibroblasts to cement eluates are not well understood. This study examines the impact of two light-polymerizing units (LPUs) on the physical and chemical properties of two SARCs under simulated clinical conditions, as well as the subsequent response of human gingival fibroblasts (hGFs) to these eluates. Methods: Dental cement discs of SARCs were polymerized using Kerr DemiPlus and 3 M Elipar DeepCure-S LED LPUs with or without a 2-mm thick zirconia screen. Physical properties (microhardness, surface roughness, residual monomers) were evaluated. hGFs' cell viability, wound healing potency, and gene expression were assessed. Results: Both Maxcem and RelyX exhibited reduced microhardness and increased surface roughness when polymerized through zirconia or with DemiPlus LPU. Higher residual monomers (HEMA and GDMA in Maxcem; TEGDMA in RelyX) concentration was observed with DemiPlus and zirconia polymerization. Maxcem polymerized with DemiPlus exhibited lower cell viability, impaired healing, and altered gene expression in hGFs compared to those polymerized with Elipar LPU. Gene expression changes included downregulated NRF2 and HO-1 and upregulated CCR-3. Conclusions: Light-polymerizing Maxcem through zirconia with DemiPlus LPU compromised SARCs' properties, leading to higher residual monomers and negatively impacting hGFs' viability, healing, and gene expression. Careful material selection and polymerization techniques are crucial to minimize adverse effects on surrounding tissues. Clinical significance: Clinicians should exercise caution when using LPUs and SARCs, especially when polymerizing through zirconia. This will help optimize the physical and chemical properties of SARCs and minimize potential adverse effects on the surrounding gingival soft tissues. [ABSTRACT FROM AUTHOR]

Background: Complicated crown-root fractures are a type of tooth fracture that involves the enamel, dentin, and cementum and accompanied by pulp exposure. The treatment of a complicated crown-root fracture is always challenging due to the difficulties in achieving a hermetic seal and a stable restoration with a fracture level close to the crestale bone level. This study aimed to evaluate and compare the efficacy of single-visit and multi-visit approaches for fragment reattachment in complicated crown-root fractures of anterior teeth. Methods: Two cohort consist of 10 adolescent patients in each group at both genders, who suffered from permanent anterior tooth complicated crown-root fracture were included. Fragment reattachment with root canal treatment was performed with either single or multiple-visit approach. Single visit fragment attachement combined with root cannel therapy was conducted in single-visit approach group immediately after injury. Fragment attachment, root cananel therapy and post resoration were performed during three times ' clinical visit in multi-visit approach group. Results: All the patients in both groups achieved satisfactory aesthetic results one year after fragment reattachment. Patients who underwent a multi-visit approach had a significantly shorter operative duration, less intra-operative pain and fatigue, slightly better periodontal health at an early stage, and a decreased incidence of temporomandibular joint disorders compared to those who underwent a single-visit approach. However, multiple visits approach may increase the risk of fragment detachment postoperatively. Conclusion: Fragment reattachment a reliable but temporary technique for adolescent patients who have suffered from complicated crown-root fractures. Multi-visit approach showed similar effecacy to single-visit approach but with slightly less complications. The choose of these two merhos should depend on the specific patient situation and patient compliance. Trial registration: This prospective cohort study was retrospectively registered in Chinese Clinical Trial Registry (ChiCTR2300076811) on 19/10/2023. [ABSTRACT FROM AUTHOR]

The central aim of adhesive dentistry is to improve the compatibility between current adhesives and a range of substrates by employing diverse application techniques. Therefore, the overarching objective of this review is to offer a comprehensive analysis of dentin bonding systems, starting with an introduction to adhesion and a detailed overview of enamel and dentin structures, their histology, and the impact of dentin structure on resin–dentin bonding. It covers the mechanisms of resin–dentin bonding, including resin adhesive application, bonding mechanisms, and factors influencing efficacy. Further, this review explores the composition of resin adhesive systems, including acidic components, cross-linking monomers, solvents, and other critical elements. It also examines various adhesive strategies—etch-and-rinse, self-etch, and universal adhesives—highlighting their applications and advantages. The review extends to clinical applications of dental adhesion, including direct restorations, indirect restorations, and immediate dentin sealing (IDS), demonstrating the practical implications of adhesive systems in enhancing restoration longevity and performance. In conclusion, despite significant advancements, no gold-standard method for optimal adhesion exists. Each adhesive system has distinct strengths and limitations. The review emphasizes the importance of evaluating methods for achieving durable adhesion and staying current with technological advancements in adhesive systems. Summary: This review provides a thorough analysis of dentin bonding systems, delving into the structures and bonding mechanisms of both enamel and dentin. By exploring various adhesive systems and their components, it highlights the ongoing challenges in achieving optimal resin–dentin adhesion. The review also addresses the clinical applications of dental adhesion, including direct restorations, indirect restorations, and immediate dentin sealing (IDS), illustrating how different adhesive techniques impact clinical outcomes. It underscores the necessity for continuous innovation and assessment of adhesive systems to enhance long-term bonding effectiveness in clinical practice. [ABSTRACT FROM AUTHOR]

Background and Aims: The bond strength of direct composite restoration to the caries affected dentin is a challenging issue. Preparation of dentin with an antibacterial agent is a method for creating durable bonded restorations. The aim of this study was to investigate the effect of curcumin photosensitizer on the bond strength of a universal adhesive to the caries-affected dentin (CAD). Materials and Methods: In this experimental in vitro study, forty-four decayed human molar teeth were selected. After removing the surface enamel and dentin by a water-cooled saw, the decayed mid-coronal dentin was stained with a caries detection solution. The green and soft infected dentin was removed and CAD and hard and healthy surrounding dentin were left. Then, the remaining dentin surfaces were treated by 600 grit silicon carbide papers and polished. The specimens were divided into two groups (n=22): dentin pretreatment group by curcumin and control with no dentin pretreatment group by curcumin. Each group was divided into two subgroups based on the method of application of All-Bond Universal adhesive (Bisco, USA) (etch and rinseand self-etching methods). After placing the Aelite All Purpose Body (Bisco, USA) composite, all specimens were placed in a universal testing machine for microshear bond strength (µSBS) test. The failure mode of the isolated surfaces was evaluated under a stereomicroscope. Two-way ANOVA analysis was used for statistical analysis. Results: Based on the obtained results, intervention with the adhesive application method and surface pretreatment with curcumin had no significant effect on the bond strength. Also, there was no significant difference in the bond strength of the curcumin group in both etch and rinse and self-etching methods (SE=56.3±27.11 MPa; ER=52.4±84.11 MPa) (P=0.847). In the curcumin-free group, there was no significant difference between the two different adhesive application methods (P=0.187). Conclusion: The results obtained in the present study showed that the pretreatment of dentin affected by caries with light-sensitive curcumin and also use of a universal adhesive by either self-etching or self-etchinf methods had no influence on the microshear bond strength of the composite restoration. [ABSTRACT FROM AUTHOR]

Background: Partial coverage concepts have met the main goal of conservative dentistry. Vonlays, which combine features of veneers and onlays, are a recent alternative to full coverage designs and overlay partial coverage restorations. This in vitro study was conducted to compare the fracture resistance of the newly introduced pressable zirconia-reinforced lithium silicate with pressable lithium disilicate ceramic and to determine the optimal preparation design for partial coverage on upper premolars. Methods: Fifty-two duplicated epoxy resin dies were prepared following vonlay and overlay preparation guidelines. For each preparation (n = 26), the specimens were divided into two subgroups to be restored with lithium disilicate (IPS e.max Press) or zirconia-reinforced lithium silicate (Vita Ambria) (n = 13 each). Ceramic vonlays and overlays were bonded using dual cure resin cement, subjected to thermomechanical fatigue, and the load to fracture was tested by using a universal testing machine. The specimens were fractographically analyzed via scanning electron microscopy (SEM). The normality of the fracture resistance data was checked using the Shapiro‒Wilk test and Q‒Q plots, and two-way ANOVA was used to assess the effect of the type of preparation and ceramic material on the fracture resistance. Results: The group of overlays restored with zirconia-reinforced lithium silicate showed the highest mean fracture load (1218.69 N), while the group of vonlays restored with lithium disilicate had the lowest mean fracture resistance (967.15 N). The effect of preparation design and material type on fracture resistance was significant for both factors, p = 0.003 and p < 0.0001, respectively. Different features of the fracture surfaces, such as arrest lines, hackles, and directions of crack propagation, were observed. Conclusions: Zirconia-reinforced lithium silicate exhibited greater resistance to fracture compared to lithium disilicate, making it a potential substitute for partial coverage restorations. Additionally, the overlay showed superior fracture resistance when compared to the vonlay preparation design. [ABSTRACT FROM AUTHOR]

Background: Over the past decade, 3D printing technology has revolutionized various fields, including dentistry. Provisional restorations play a crucial role in prosthetic rehabilitation, necessitating the evaluation of their bond strength with different provisional cement agents. Aims: This study is aimed at assessing the immediate and long‐term bond strength of 3D‐printed dental crowns using three provisional cement agents. Materials and Methods: Provisional crowns (N = 36) were manufactured using 3D modeling software and cemented in dentin analogues (G10 Nema resin). After the crowns' fabrication, they were randomly divided into three groups (n = 12) for cementation with Relyx Temp 3M ESPE, Provicol—VOCO, and Meron—VOCO. Tensile strength tests were conducted using a universal testing machine, with half of the specimens subjected to 2000 thermal cycles before testing. Finite element analysis was employed to assess tensile stress distribution. Results: Statistical analysis (two‐way ANOVA and Tukey's test at a 95% confidence level) revealed significant effects of cement type (p = 0.006) and thermal aging (p = 0.001) on bond strength. Glass ionomer cement exhibited the highest immediate resistance, while all types of cement were adversely affected by thermal aging, resulting in decreased bond strength. Conclusion: Thermal aging significantly alters the properties of 3D printing resin and affects the bond strength of provisional cement with 3D‐printed crowns. Despite the adverse effects of thermal aging, glass ionomer cement demonstrated the highest immediate resistance. Clinicians should carefully consider these findings when selecting provisional cements for 3D‐printed crowns. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to examine the shear bond strength (SBS) of repair material to conventionally, subtractive‐, and additive‐manufactured denture bases after different surface treatments. Materials and Methods: Disk‐shaped test specimens (N = 300) were prepared from denture base materials produced by one conventional (Procryla), one subtractive (Yamahachi), and one additive (Curo Denture) method. The test specimens were randomly divided into five groups (n = 10) and exposed to a variety of surface treatments—Group A: no surface treatment; Group B: grinding with silicon carbide paper; Group C: sandblasting; Group D: erbium: yttrium‐aluminum‐garnet laser; and Group E: plasma. Repair was performed with autopolymerizing acrylic resin (Meliodent). Surface roughness analyses were performed with a profilometer. Scanning electron microscopy was used to examine one specimen from each subgroup. SBS was evaluated on a universal testing machine. Failure types were observed under a stereomicroscope. Results: Surface roughness values were significantly higher in all test materials in Group D than in the other groups (p < 0.001). For conventional resin, the SBS values were higher in Group C than in Groups A, D, and E (p < 0.001). For CAD/CAM material, Groups B and C had significantly greater SBS increases compared with Group E (p < 0.001). For 3D material, Group D showed higher SBS than all groups except Group C (p < 0.001). Conclusions: For SBS, sandblasting was most effective in the conventional group, whereas laser treatment was the most effective in the additive‐manufactured group. For the subtractive group, surface treatments other than plasma exhibited similar SBS. Clinical Significance: In repairing fractured prostheses, any degree of roughening suitable for the material content may provide an SBS benefit. [ABSTRACT FROM AUTHOR]

Background: Contemporary fixed orthodontic appliances are shifting from non‐customized pre‐adjusted appliances to custom‐designed and printed appliances with novel digital setup systems. We are one step closer to precision dentistry and orthodontics using personalized mechanics and custom appliances. However, despite the evidential enhancement and other improvements to fixed appliances, tooth movement is still limited to five degrees of freedom. Opening or closing spaces still requires manually placing elastomeric chains or coil springs. Aim: In this article, we aimed to demonstrate how advancements in CAD/CAM technology, reverse engineering, and digital customization are helping orthodontics constantly evolve, enabling treatment with enhanced esthetics and minimal compliance. The clinical system (InBrace®, Irvine, CA) described in this article uses a patient‐specific, digitally designed multiloop NITI wire that delivers friction‐free, light, and continuous forces and activates automatically whenever the malocclusion deviates from the digital setup. Conclusion: Through digital customization, InBrace allows for automated tooth movement in all six degrees of freedom, including space opening or closure, via programmed non‐sliding mechanics. Clinical Significance: Precision orthodontics and personalized treatment have been significant developments in orthodontics recently. This article focuses on how a technologically advanced lingual appliance system could achieve targeted cosmetic results methodically via automation and personalization. [ABSTRACT FROM AUTHOR]

This in vitro study evaluated the influence of radiant exposure and material shade on the degree of conversion (DC) and microhardness of a resin-based composite (RBC). Sixty-four RBC specimens in shades A1E (enamel) and A4D (dentin) were light cured at a calibrated exitance of 1000 mW/cm² for 5, 10, 15, or 20 seconds, resulting in radiant exposure levels of 5. 10. 15 or 20 J/cm². The DC was determined using Fourier-transform infrared spectroscopy (n = 3 per shade per exposure level). The Knoop hardness number (KHN) was measured on the top and bottom surfaces of each specimen (n = 5 per shade per exposure level). Data were analyzed using 2- and 3-way analyses of variance and post hoc Tukey tests (α = 0.05). The RBC shade did not affect the DC (P = 0.860), and the lowest DC values were achieved with an exposure level of 5 J/cm² (P < 0.001). The shade did not affect the KHN on the top surface, but the radiant exposure level did, with the application of 5 J/cm² resulting in significantly lower values (P< 0.05). For the bottom surface, shade A1E showed significantly higher KHN values than A4D (P < 0.001). An increase in the radiant exposure led to increased DC and KHN for both shades of RBC until reaching a saturation point of 10 J/cm² for A1E and the top surface of A4D. The darker and more opaque shade was not adequately polymerized at a 2-mm depth, even when the highest radiant exposure level was applied. [ABSTRACT FROM AUTHOR]

Statement of the Problem: Immediate dentin sealing (IDS) was introduced to overcome the disadvantages of delayed dentin sealing like pollution of dentin tubules, microleakage, and bond strength destruction over time. The effect of IDS on the bond strength of indirect restorations is still debatable. Purpose: This study was conducted to determine the effect of IDS on the bond strength of ceramic restorations to dentin. Materials and Method: In this systematic review and meta-analysis, the study protocol was registered on the PROSPERO database under the registration number CRD420202014 27. MEDLINE (PubMed), Web of Science, Scopus, and ProQuest databases were searched until January 2021 and updated in January 2022. Worldcat.org and Opengrey.eu, ProQuest dissertation and thesis, and Google Scholar were searched to explore the grey literature. The in vitro studies evaluating the bond strength of ceramic restoration to dentin with and without IDS were included. Seven criteria were assessed to evaluate the risk of bias in the study. Statistical analyses were conducted using RevMan 5.3. The inverse variance method was used to determine the mean difference of micro-tensile bond strength (µTBS) and shear bond strength (SBS). Results: A total of 10 studies (20 datasets) were included in the meta-analysis. Regarding the µTBS analysis, IDS had a significantly higher bond strength than Delayed Dentin Sealing (DDS) (MD:1.16, 95%CI:0.28_2.03, I² =0%). However, no significant difference was found between them in the SBS analysis (MD:0.25, 95%CI: -0.56-1.06, I² =96%). All studies were categorized to have a moderate or high risk of bias. Conclusion: Most in vitro evidence showed favorable results for the effect of IDS on the bond strength and durability of indirect restorations. The adhesive system and the type of ceramic and its treatment before cementation are determining factors. Due to the heterogeneity of the outcomes and studies with a moderate/high risk of bias, the quality of the evidence was low. [ABSTRACT FROM AUTHOR]

Objective: This systematic review evaluated how different storage times and conditions affect universal adhesives' bond strength and degree of conversion (DC). Methods: A literature search was conducted in PubMed, Scopus, Web of Science, and Google Scholar databases for articles published from January 1st, 2000, until May 15th, 2022. The researchers comprehensively evaluated the articles using a multi-step process to identify articles relevant to the topic of interest. Quality assessment was performed through the ROBDEMAT tool. Due to the high heterogeneity in the preliminary data, performing a meta-analysis was not feasible. Results: A total of 3169 records were obtained, and after removing duplicates, 2267 remained. Following title and abstract screening, 2253 studies were excluded based on the predetermined exclusion criteria. Of the 14 remaining studies, seven were further excluded due to the use of non-universal adhesives, experimental adhesives, or lack of aging protocols. Ultimately, seven studies were included in this systematic review. All studies focused on bond strength, with only one addressing DC. The Findings showed that aging or different storage conditions generally led to reduced bond strength and DC values in universal adhesives, although exceptions with stable or improved properties were noted. Conclusions: Adhesives with higher pH and those containing methacrylamides, HEMA-free compositions, or hydrolytically stable monomers showed better durability than others. Strict adherence to storage instructions, lower storage temperatures, and immediate recapping of adhesive bottles after use is recommended to maintain adhesive properties. These findings provide insights for optimizing the long-term performance of universal adhesives in clinical settings. [ABSTRACT FROM AUTHOR]

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Abstract In this multi-parameter study, the effect of diverse factors related to adhesive application on the activation of host-derived gelatinases was investigated by gelatin zymography, in-situ zymography, fluorogenic DQ-gelatin assay and micro-tensile bond-strength (μTBS) testing. Gelatin zymography disclosed the presence of gelatinases in phosphoric acid-etched dentin powder, while two gold-standard adhesives generated no measurable MMP activation. In-situ zymography revealed that the interfacial gelatinolytic activity from specimens treated with the two adhesives appeared similar as that of the EDTA negative control, indicating no detectable gelatinases were activated upon adhesive treatment. In solution, MMP-2/9 activity significantly decreased upon interaction with both adhesives (two-way linear mixed effects model [LMEM]: p 0.05). Taken together, the two adhesives did not activate but rather inhibited the release and activation of dentinal gelatinases.

Objective: This systematic review evaluated how different storage times and conditions affect universal adhesives' bond strength and degree of conversion (DC).Methods: A literature search was conducted in PubMed, Scopus, Web of Science, and Google Scholar databases for articles published from January 1st, 2000, until May 15th, 2022. The researchers comprehensively evaluated the articles using a multi-step process to identify articles relevant to the topic of interest. Quality assessment was performed through the ROBDEMAT tool. Due to the high heterogeneity in the preliminary data, performing a meta-analysis was not feasible.Results: A total of 3169 records were obtained, and after removing duplicates, 2267 remained. Following title and abstract screening, 2253 studies were excluded based on the predetermined exclusion criteria. Of the 14 remaining studies, seven were further excluded due to the use of non-universal adhesives, experimental adhesives, or lack of aging protocols. Ultimately, seven studies were included in this systematic review. All studies focused on bond strength, with only one addressing DC. The Findings showed that aging or different storage conditions generally led to reduced bond strength and DC values in universal adhesives, although exceptions with stable or improved properties were noted.Conclusions: Adhesives with higher pH and those containing methacrylamides, HEMA-free compositions, or hydrolytically stable monomers showed better durability than others. Strict adherence to storage instructions, lower storage temperatures, and immediate recapping of adhesive bottles after use is recommended to maintain adhesive properties. These findings provide insights for optimizing the long-term performance of universal adhesives in clinical settings.

This systematic review evaluated the effect of different hydrofluoric acid (HF) etching regimens and a self-etch ceramic primer (SECP) on the flexural strength (FS) and fatigue failure load (FFL) of glass-ceramic materials.The identification of relevant studies was conducted by two authors in five databases: PubMED, Scopus, Web Of Science, LILACS and Virtual Health Library (BVS) until July 2022 with no year limit. The analysis was conducted in RevMan 5.4.1 Software (Cochrane Collaboration) using Random effect model at 5 %. The risk of bias of the included studies were assessed. From the 5349 articles identified, 34 were included for quantitative analysis. Meta-analysis showed that for predominantly glassy ceramics, etching with HF 5 % had no significant impact on FS, however, HF acid etching with concentrations greater than 5 % negatively impacted FS. For lithium disilicate glass-ceramics (LDGC) HF acid etching, negatively influenced FS, while increasing the FFL. HF etching negatively affected FS of hybrid ceramics. The self-etch ceramic primer and HF acid etching showed a similar impact on FFL and FS. This meta-analysis indicates that the impact of SECP and HF acid etching on the mechanical behavior of glass ceramics is material-dependent.

Statement of the Problem: One of the most important factors in the clinical longevity of composite resin restorations is proper adhesion, which is achieved using phosphoric acid. Different phosphoric acid products might affect the micro-shear bond strength of composite resin to enamel. Purpose: The present study aimed to evaluate the micro-shear bond strength of composite resin to sound enamel using six different brands of acid-etch agents. Materials and Method: The present in vitro study was carried out on 72 extracted sound human (mandibular and maxillary) first premolar teeth. The teeth crowns were divided into two equal parts with a mesiodistal cut and randomly assigned to six groups in terms of the acid etchant brand: Ultra-etch, SDI, Morvabon, FGM, Nik Darman, and Experimental. The bonding procedure was carried out using the Margin Bond enamel adhesive. Tygon tubes (1×0.7 mm) containing composite resin were bonded to each enamel surface. After 24 hours of storage in distilled water, each sample underwent a shearing force with a crosshead speed of 0.5 mm/min. The morphologic changes were evaluated using scanning electron microscopy. The data were analyzed with SPSS using one-way ANOVA and Tukey test (p< 0.05). Results: One-way ANOVA showed that micro-shear bond strength in different etchant agents have significant differences (p< 0.001). The highest and lowest composite resin micro-shear bond strengths belonged to Ultradent and SDI brands, respectively. The enamel surfaces in the SDI group revealed residual debris after dissolution. Conclusion: Preparation of the enamel surface with different phosphoric acid products might affect the micro-shear bond strength and enamel surface morphology differently. Further clinical studies are suggested to evaluate the effect of different types and concentrations of acid etching agents on the enamel and dentin bonds. [ABSTRACT FROM AUTHOR]

Objective: The aim of this case report was to present a minimally invasive and esthetic treatment approach for the replacement of missing teeth removable partial dentures retained by zirconia ceramic resin-bonded attachments. Method and materials: The resin-bonded attachments were digitally designed and milled using CAD/CAM technology from monolithic 3Y-TZP zirconia ceramic. The resin-bonded attachments had an optimized attachment design approved for zirconia ceramic. The preparation was based on general preparation guidelines for resin-bonded attachments and resin-bonded fixed dental prostheses (RBFDPs). After placement of rubber dam, the resin-bonded attachments were bonded with a phosphate monomer-containing luting resin. Results: The presented resin-bonded attachment-retained removable partial denture was successful over 30 months of clinical observation without any complications. The patient was satisfied with the minimally invasive treatment procedure. Conclusion: Zirconia ceramic resin-bonded attachments fabricated with a special attachment design are an esthetic and minimally invasive treatment approach. However, clinical data on the long-term outcome of zirconia resin-bonded attachments are still needed. [ABSTRACT FROM AUTHOR]

Background: This systematic review aims to critically assess the literature on the debonding process of orthodontic brackets from enamel surfaces. The review evaluates Randomized Controlled Trials (RCTs) to determine the effectiveness and implications of various debonding techniques and materials. Methods: The study followed PRISMA guidelines, selecting RCTs published from 1999 onwards that compared the outcomes of various orthodontic bracket debonding techniques. Selection criteria included studies utilizing human teeth, with outcomes such as enamel surface roughness and Adhesive Remnant Index (ARI) analyzed. Data sources included PubMed, Scopus, Web of Science, and the Cochrane Library. Results: Out of 1,587 records identified, five studies met the inclusion criteria. These studies provided comparative data on the effectiveness of various debonding techniques, including tungsten carbide and diamond burs, in minimizing enamel damage and optimizing adhesive removal. Findings indicated that tungsten carbide burs produced the least enamel roughness. Discussion: Utilizing tungsten carbide burs for debonding orthodontic brackets significantly minimizes enamel surface roughness and potential damage, thereby enhancing the preservation of enamel integrity post-treatment. The systematic review highlights current debonding techniques are effective in adhesive removal, and the choice of instrument significantly affects enamel integrity and clinical outcomes. The findings support the need for continuous improvement and innovation in removing braces to improve orthodontic treatment results and patient satisfaction.

Background: Adhesion to zirconia remains a significant dental challenge. This study is aimed at assessing the bond strength of zirconia based on surface treatment with pre or postsintering sandblasting associated with different chemical treatments and resin cements. Methods: Zirconia blocks were divided into 12 experimental groups based on the surface treatment (presintering sandblasting or postsintering sandblasting/tribochemical abrasion treatment), chemical treatment (none, Single Bond Universal, or Signum Zirconia Bond), and choice of cement (Panavia F or RelyX™ U200). The bond strength was measured by shear tests using a universal testing machine. The fracture analysis was performed using stereomicroscopy. Data were analyzed using three‐way ANOVA and Tukey's test (α = 5%). Results: Triple and double factor's interactions were not significant (p > 0.05). Regarding the surface treatment factor, the bond strength following postsintering sandblasting treatment associated with tribochemical abrasion (9.15 ± 3.62 MPa) was significantly higher than presintering sandblasting treatment (5.24 ± 3.53 MPa). Concerning the chemical treatment factor, bond strengths were ranked as follows: Signum Zirconia Bond > Single Bond Universal > no treatment. The bond strength of the resin cements did not differ among them. Most fractures (67%) were classified as adhesive, and 32% were categorized as mixed fractures. Conclusion: Surface treatment via postsintering sandblasting combined with tribochemical abrasion demonstrated superior efficacy than in presintering sandblasting. Additionally, chemical treatment with zirconia primer increased the bond strength of zirconia irrespective of the surface physical treatment. [ABSTRACT FROM AUTHOR]

Background: Digitally fabricated dentures may require relining due to continual alveolar ridge resorption. However, studies evaluating the tensile bond strength (TBS) of digitally fabricated dentures bonded to denture liners are lacking. This study aimed to evaluate the TBS of autopolymerized, heat-polymerized, milled, and 3D printed denture base materials bonded to 2 acrylic-based and 2 silicone-based denture liners, both before and after thermocycling. Additionally, the impact of thermocycling on the TBS were also evaluated. Methods: The TBS of 4 different denture base materials (Palapress (PL), Vertex Rapid Simplified (VR), Smile CAM total prosthesis (SC), and NextDent denture 3D+ (ND)) bonded to 2 acrylic-based (GC Soft-Liner (GC) and Tokuyama Rebase II (RB)) and 2 silicone-based (Ufi Gel P (UP) and Sofreliner Tough M (ST)) denture liners were tested. Specimens (n = 8) were divided into non-thermocycling and thermocycling groups. Non-thermocycling specimens were tested after 24-hours water immersion, while thermocycling specimens were underwent 5000 cycle and were immediately tested. Mode of failure was examined under a stereomicroscope. Data were analyzed using 2-way ANOVA and Tukey HSD tests (α = 0.05), and independent samples t test (α = 0.05) for TBS between non-thermocycling and thermocycling groups. Results: For the non-thermocycling groups, within the same denture liner material, no significant differences were found between denture base materials, except the ND + RB group, which had significantly lower TBS. For the thermocycling groups, within the same denture liner material, the TBS in the PL group exhibited the highest and the ND group exhibited the lowest. Within the same denture base material, in both non-thermocycling and thermocycling groups, the TBS in the ST group exhibited the highest; in contrast, that in the GC group exhibited the lowest. No significant differences were observed in TBS between non-thermocycling and thermocycling groups, except for denture base materials bonded to the ST group, SC + UP, and ND + UP groups. Conclusions: Milled denture base can be relined with acrylic-based or silicone-based denture liner. However, cautions should be exercised when relining 3D printed denture base. Thermocycling did not affect TBS between acrylic-based denture liners and denture bases. In contrast, it affected the bond between silicone-based denture liner and denture base. [ABSTRACT FROM AUTHOR]

Objectives: To investigate the effect of neutral 10-methacryloyloxydecyl dihydrogen phosphate salt (MDP-Na) on the dentin bond strength and remineralization potential of etch-&-rinse adhesive. Methods: Two experimental etch-&-rinse adhesives were formulated by incorporating 0 wt% (E0) or 20 wt% (E20) neutral MDP-Na into a basic primer. A commercial adhesive, Adper Single Bond 2 (SB, 3 M ESPE), served as the control. Sixty prepared teeth were randomly allocated into three groups (n = 20) and bonded using either one of the experimental adhesives or SB. Following 24 h of water storage, the bonded specimens were sectioned into resin-dentin sticks, with four resin-dentin sticks obtained from each tooth for microtensile bond strength (MTBS) test. Half of the sticks from each group were immediately subjected to tensile loading using a microtensile tester at a crosshead speed of 1 mm/min, while the other half underwent tensile loading after 6-month incubation in artificial saliva (AS). The degree of conversion (DC) of both the control and experimental adhesives (n = 6 in each group) and the adsorption properties of MDP-Na on the dentin organic matrix (n = 5 in each group) were determined using Fourier-transform infrared spectrometry. Furthermore, the effectiveness of neutral MDP-Na in promoting the mineralization of two-dimensional collagen fibrils and the adhesive-dentin interface was explored using transmission electron microscopy and selected-area electron diffraction. Two- and one-way ANOVA was employed to assess the impact of adhesive type and water storage on dentin bond strength and the DC (α = 0.05). Results: The addition of MDP-Na into the primer increased both the short- and long-term MTBS of the experimental adhesives (p = 0.00). No difference was noted in the DC between the control, E0 and E20 groups (p = 0.366). The MDP-Na remained absorbed on the demineralized dentin even after thorough rinsing. The intra- and extra-fibrillar mineralization of the two-dimensional collagen fibril and dentin bond hybrid layer was confirmed by transmission electron microscopy and selected-area electron diffraction when the primer was added with MDP-Na. Conclusions: The use of neutral MDP-Na results in high-quality hybrid layer that increase the dentin bond strength of etch-&-rinse adhesive and provides the adhesive with remineralizing capability. This approach may represent a suitable bonding strategy for improving the dentin bond strength and durability of etch-&-rinse adhesive. [ABSTRACT FROM AUTHOR]