Bleaching efficacy and quality of life of different bleaching techniques - randomized controlled trial.

OBJECTIVES: To evaluate bleaching efficacy and oral health-related quality of life (ORHQoL) of three bleaching systems with similar hydrogen peroxide (HP) concentration for up to 6 months post-treatment. MATERIALS AND METHODS: A randomized controlled trial was designed with three parallel groups: group A - in-office 6% HP paint-on varnish; group B - at-home 6% HP with adaptable tray; group C - at-home 16% carbamide peroxide with custom tray. At three different stages (baseline, after bleaching, and 6-month follow-up), ORHQoL was evaluated by the OHIP-14 questionnaire and tooth color of the upper canines and central incisors were measured by two shade guides and a spectrophotometer (measuring CIE L*a*b* with respective color/whiteness differences - ΔE00/ΔWID). Results were presented as mean and 95% confidence intervals and statistical tests were performed appropriately, considering a significance level of α = 0.05. RESULTS: All groups presented significant color differences (P < 0.05) between all stages, with ΔE00/ΔWID surpassing the perceptibility threshold in 98% cases, with group C's results being significantly (P < 0.05) higher when compared to other groups, although with significantly (P < 0.05) higher values of color relapse. Significative ORHQoL improvements (P < 0.05) were detected after bleaching in a global analysis with no differences between techniques. CONCLUSIONS: All techniques presented bleaching efficacy, color stability, and improvements in ORHQoL up to 6 months post-treatment. CLINICAL SIGNIFICANCE: Clinicians may consider both at-home and in-office bleaching techniques with 6% HP to attain long-lasting satisfactory clinical results while producing positive changes in ORHQoL.

HIV-1 impact on oral health-related quality of life: a cross-sectional study.

This cross-sectional study compared the Oral-Health-Related Quality of Life (OHRQoL) in HIV negative patients (Group 1, n=129, mean age: 39.9 ± 15.6, 75 females) and HIV+ patients (Group 2, n=670, mean age: 43.2 ± 9.8, 246 females) from the same socio-economic environment using the OHIP-49 questionnaire. OHIP total score were determined by simple summing. A multiple linear regression model was carried out to predict OHIP scores in which HIV+ patients experienced a significantly (p<0.001) worst OHRQoL for total and every dimension. A general linear model was used for estimating the means in the two groups adjusted for covariates included in the previous model. Adjusted means for subscale and total OHIP scores were significantly higher for Group 2 (61.6 ± 6.26 vs. 119.8 ± 3.31) with a large effect size (0.94). HIV+ infection, decayed teeth, prosthodontic and surgical needs, care index, drug use, employment and age presented an independent effect on questionnaire scores. This study shows that HIV+ infection has an independent and negative impact on the OHRQoL while care index presents a positive impact. Additional factors like high decayed teeth, prosthodontic treatment needs and drug use are independently associated with total OHIP scores, presenting a negative effect on OHRQoL.

Bioactive-Enhanced Polyetheretherketone Dental Implant Materials: Mechanical Characterization and Cellular Responses.

The aim of this study was to characterize the mechanical properties of a bioactive-modified polyetheretherketone (PEEK) manufacturing approach for dental implants and to compare the in vitro biological behavior with titanium alloy (Ti6Al4V) as the reference. PEEK, PEEK with 5% hydroxyapatite (HA), PEEK with 5% beta-tricalcium phosphate (ßTCP), and Ti6Al4V discs were produced using hot pressing technology to create a functionally graded material (FGM). Surface roughness values (Ra, Rz), water contact angle, shear bond strength, and Vickers hardness tests were performed. Human osteoblasts and gingival fibroblasts bioactivity was evaluated by a resazurin-based method, alkaline phosphatase activity (ALP), and confocal laser scanning microscopy (CLSM) images of fluorescent-stained fibroblasts. Morphology and cellular adhesion were confirmed using field emission gun-scanning electron microscopy (FEG-SEM). Group comparisons were tested using analysis of variance (Tukey post hoc test), α = .05. All groups presented similar roughness values (P > .05). Ti6Al4V group was found to have the highest contact angle (P < .05). Shear bond strength and Vickers hardness of different PEEK materials were similar (P > .05); however, the mean values in the Ti6Al4V group were significantly higher when compared with those of the other groups (P < .05). Cell viability and proliferation of osteoblast and fibroblast cells were higher in the PEEK group (P < .05). PEEK-ßTCP showed the highest significant ALP activity over time (P < .05 at 14 days of culture). An enhanced bone and soft-tissue cell behavior on pure PEEK was obtained to the gold standard (Ti6Al4V) with equivalent roughness. The results substantiate the potential role of chemical composition rather than physical properties of materials in biological responses. The addition of 5% HA or ßTCP by FGM did not enhance PEEK mechanical properties or periodontal cell behavior.

Patient-related outcomes in Sjögren syndrome treated with stimulants of salivary secretion: Randomized clinical trial.

OBJECTIVES: To investigate the impact of gustatory stimulants of salivary secretion (GSSS) on Sjögren's syndrome patients' self-perception of xerostomia, oral health-related quality of life (OHRQoL) and salivary secretion. METHODS: A total of 110 Sjögren's syndrome patients were randomly allocated to be treated with either a malic acid lozenge or a citric acid mouthwash and then crossed over. Before and after the interventions, the Xerostomia Inventory 5 (SXI-5-PL) and the Oral Health Impact Profile (OHIP-14-PT) questionnaires (both in the Portuguese language) were administered to patients. Unstimulated, mechanical and gustatory-stimulated salivary flows were determined. Repeated measures and between-subject analyses were performed. Statistical significance was set at 5%. RESULTS: After the intervention and within each group, both GSSS elicited a reduction in the SXI-5-PL and OHIP-14-PT scores and an increase in salivary output, significant in the malic acid lozenge group. The malic acid treatment resulted in a greater effect size and percentage improvement than citric acid mouthwash. The malic acid lozenge also produced a significant greater salivary output than the citric acid rising solution. CONCLUSIONS: In Sjögren's syndrome patients, lozenges containing malic acid increased saliva production and xerostomia relief, resulting in improved quality of life.

Laser Nd:YAG patterning enhance human osteoblast behavior on zirconia implants.

Zirconia has been regarded as a promising material for dental implants, and Nd:YAG laser treatment has been proposed as a potential strategy to improve its bioactivity. The main aim of the present study was to evaluate the in vitro behavior of human fetal osteoblasts in contact with laser-textured zirconia implant surfaces assessing the effect of different texture patterns, spacing between laser passes and number of laser passes. Zirconia discs were produced and treated with Nd:YAG laser according to test group variables: texture (microgrooves and micropillar array), distance between surface features (25 µm, 30 µm and 35 µm), and laser passes [1, 2, 4, and 8]. Untextured sandblasted and acid-etched zirconia discs (SBAE) were used as controls. Human osteoblasts (hFOB 1.19) were cultured for 14 days on test and control samples. Morphology and cellular adhesion were observed using scanning electron microscopy (SEM). Cell viability and proliferation were evaluated at 1, 3, 7, and 14 days using a commercial resazurin-based method. Collagen type I was evaluated at 3 days using ELISA. Alkaline phosphatase (ALP) activity was evaluated at 7 days using a colorimetric enzymatic technique. Group comparisons were tested using ANOVA or Mann-Whitney test (Tukey's post hoc) using statistical software, and significance was set at p < 0.05. Cell viability and proliferation increased over time for all groups with statistically higher values for laser-textured groups when compared with control at 7 and 14 days in culture (p < 0.05). Collagen type I levels were higher for study groups (p < 0.05) when compared with control group. No statistically differences were detected for ALP activity levels between texture and control groups (p > 0.05). The results suggest that laser-machined zirconia implant surfaces may benefit biological osteoblast response. However, the type of texture, spacing at the range of 25-35 µm, and number of laser passes did not seem to be relevant variables.

Dental prophylaxis influence in tooth color assessment-Clinical study.

OBJECTIVE: To evaluate dental prophylaxis influence in tooth color assessment with the use of different methods. MATERIALS AND METHODS: Volunteers were consecutively recruited and screened according to appropriate inclusion/exclusion criteria. Each participant's upper right central incisive and canine color was measured before and after dental prophylaxis with a one-week interval. Tooth color assessment was performed by calibrated operators and the patient using a VITA Classical shade guide and by spectrophotometric methods with a proper device (SpectroShade). Color was reported as mean with SD of Commission Internationale De l'Eclairage (CIE) L*a*b* values, ΔEab and ΔE00 . One-way analysis of variance and Tukey post hoc were performed to assess differences between methods and paired t test for assessing differences in tooth color coordinates after dental prophylaxis. Values of P < .05 were taken as significant. RESULTS: Fifty patients were included. Self-assessed dental prophylaxis effects equated to a significantly different mean ΔE00 value of 2.3 ± 1.7 (P < .01), when compared to the calibrated operator reported 0.8 ± 1.1 and the spectrophotometer 1.0 ± 0.5. Half of volunteer's ΔE00 values surpassed the acceptability threshold, when compared to 28% from investigator and 10% from spectrophotometer. CONCLUSION: Performing a dental prophylaxis did have an influence in tooth color perception with a higher self-perceived effect in the patient assessment. CLINICAL SIGNIFICANCE: The results of this study suggest that performing professional dental prophylaxis presented a perceived effect in tooth color regardless of the method used being that patients precepted whiter and less yellowish teeth. Since extrinsic stain is considered as one of the factors that could influence tooth color assessment, performing professional dental prophylaxis prior to composite or ceramic color selection in anterior teeth restorations could consequently increase treatment predictability.

Soft tissue replication in single unit implant impressions-A three dimensional clinical study.

OBJECTIVE: Comparison of soft tissue replication between conventional and digital impressions for definitive single unit implant rehabilitation in the esthetic zone. MATERIALS AND METHODS: Six patients were recruited according to inclusion criteria for this cross-over pilot study and submitted to a conventional silicone implant impression with customized coping and a digital impression with an intraoral scanner. Stereolithography files obtained from the same patient were superimposed with appropriate software and trueness evaluated between methods at predetermined locations (56 in hard and soft tissues and 18 in the emergence profile, per patient). Results were presented as mean root mean square (RMS) ± 95% confidence interval and effect size calculated with Hedges' g ± 95%. Mann-Whitney and Kruskal-Wallis were performed when appropriate and α was set at .05. RESULTS: Trueness between methods equated to 51.08[45.68;56.47] µm and 60.46[52.29;68.62] µm in hard and soft tissues, respectively. Soft tissue replication by intraoral scanner acquisition corresponded to a statistically significant RMS of 243.89[209.15;278.63] µm equating to a Hedges' g of 1.52[1.22;1.82] which corresponded to a large effect size. CONCLUSIONS: The proposed method could be considered for soft tissues assessment and the results suggest that intraoral impression techniques produce statistically significant changes in peri-implant soft tissue replication, although below the clinically detectable threshold. CLINICAL SIGNIFICANCE: The proposed technique allows for the 3D determination of peri-implant tissues changes in digital models with higher sensitivity than visual techniques, thus presenting itself as a promising alternative in clinical studies and that the use of an intraoral scanner obtained significant differences in the soft tissue emergence profile replication when compared with the gold standard.

Validity and reliability of a Portuguese version of the Summated Xerostomia Inventory-5.

OBJECTIVES: The aim of this study was to validate and determine the reliability of the Portuguese version of the Summated Xerostomia Inventory. BACKGROUND: Many conditions such as head and neck radiation, autoimmune diseases or polypharmacy are characterised by hyposalivation which can affect oral and systemic quality of life. As such, this condition must be assessed, and the English version of the Xerostomia Inventory has been increasingly used to determine the severity of dry mouth perception. MATERIALS AND METHODS: This was a descriptive cross-sectional study, which employed volunteers suffering from hyposalivation after local ethical committee clearance. Each patient signed an informed consent and responded to the Portuguese version of the questionnaire in the form of an interview. This was repeated again after 2 weeks. A standard single question provided a validity check. Data were analysed using Cronbach's α to test its reliability and total and interitem correlation, and intraclass correlation to determine its internal consistency and test-retest reliability. Significance was set at .05. RESULTS: A sample of 103 volunteers was recruited. Cronbach's α was .84 and .87 for the first and second test administrations, respectively. The intraclass correlation coefficient value for the test-retest reliability was .93, and scores for the individual items ranged from .79 to .90. The correlation between the total score of the questionnaire and standard single dry mouth question was .66, indicating a very good correlation. CONCLUSION: Demonstrating excellent psychometric properties, the Summated Xerostomia Inventory (Portuguese Version) is a valid tool for quantifying Xerostomia in a dry mouth-afflicted population.

Microtensile Bond Strength and Micromorphology of Bur-cut Enamel Using Five Adhesive Systems.

PURPOSE: This study compared the microtensile bond strengths (µTBS) of two etch-and-rinse (ER) (OptiBond FL [OBFL]; Prime & Bond NT [PBNT]) and three self-etching (SE) (Clearfil SE Bond [CSEB]; Xeno III [XIII]; Xeno V+ [XV+]) adhesives systems to bur-prepared human enamel considering active (AA) and passive (PA) application of the self-etching systems. MATERIALS AND METHODS: Ninety-six enamel surfaces were prepared with a medium-grit diamond bur and randomly allocated into 8 groups to receive adhesive restorations: G1: OBFL; G2: PBNT; G3: CSEB/PA; G4: CSEB/ AA; G5: XIII/PA; G6: XIII/AA; G7: XV+/PA; G8: XV+/AA. After composite buildup, samples were sectioned to obtain a total of 279 bonded sticks (1 mm2) that were submitted to microtensile testing (µTBS; 0.5 mm/min) after 24-h water storage (37°C). Etching patterns and adhesive interfacial ultramorphology were also evaluated with confocal laser scanning (CLSM) and scanning electron microscopy (SEM). Data was analyzed with one-way ANOVA (α = 0.05). Weibull probabilistic distribution was also determined. RESULTS: Regarding µTBS, both adhesive system and application mode yielded statistically significant differences (p < 0.05) among groups. ER adhesive systems together with CSEB/AA and XIII/PA recorded the highest and statistically similar bond strength results. XV+ presented very low bond strength values, regardless of the application mode. Among self-etching adhesives, CSEB produced significantly higher µTBS values when applied actively. Qualitative evaluation by SEM and CLSM revealed substantial differences between groups both in adhesive interfaces and enamel conditioning patterns. CONCLUSIONS: ER and SE adhesive systems presented distinctive bond strengths to bur-cut enamel. The application mode effect was adhesive dependent. Active application improved etching patterns and resin interfaces micromorphology.

Origin and importance of the Latin American Kawasaki Disease Network (REKAMLATINA).

Kawasaki disease is the leading cause of acquired cardiac disease in children. Although the epidemiology of the disease has been well described in Japan, other Asian countries, Europe, Australia and North America, the epidemiology and disease burden in Latin American children is unknown. For this reason, the idea of establishing a research network on Kawasaki disease in children from Latin America was born, becoming this the largest Kawasaki disease international multinational research network and in which 20 countries of the region will be integrated.

Hyaluronic acid-based gels for oral application: Comparison of in vitro effects on gingival cells and bacteria.

Purpose: This study aimed to evaluate the cytotoxic effects of different topical hyaluronic acid-based gels on human gingival fibroblasts and oral bacteria. Methods: Four different hyaluronate gels - Bexident® Aftas (BA), GUM® AftaClear (AfC), Gengigel®(G), Aloclair® Plus (AlC) and a chlorhexidine gel - Bexident®Gums(BG) were selected. Human gingival fibroblasts (HGF) were seeded in 48-well plates with different gel/culture medium concentrations (v/v%) and cell viability was evaluated at 1 and 3 days of culture. Cell morphology was assessed, and alterations graded according to ISO 10993-5:2009(E). Streptococcus oralis CECT 907T colony was, seed on 48-well plate or spread onto the blood agar plates and exposed to the different gel's concentration. The optical density (OD) was assessed, and the diameter of the inhibition zone was measured (mm). Results: BA and G elicited reduced HGF cytotoxicity, followed by AfC. AlC and BG were cytotoxic at concentrations up to 3% for all exposure times. PCM images of HGF showed moderate-to-severe alterations for AlC and BG and slight to mild changes, for BA, AfC and G. The highest antibacterial activity against S.oralis was observed on AlC and AfC, and no antibacterial activity was observed for BA and G. Inhibitory effect in sessile colonies was only observed in AlC and BG. Conclusions: AlC demonstrated superior antibacterial activities against S.oralis but a higher cytotoxic potential in HGF. BA and G presented the lowest cytotoxicity with little to no antibacterial effect. AfC demonstrated bacteriostatic effects and low cytotoxicity on HGF.

Cellular responses to 3D printed dental resins produced using a manufacturer recommended printer versus a third party printer.

PURPOSE: The aim of this study was to evaluate the influence of different 3D dental resins, using a manufacturer recommended printer and a third-party printer, on cellular responses of human gingival cells. MATERIALS AND METHODS: Three NextDent resins (Denture 3D+, C&B MFH and Crowntec) were used to produce specimens on printers NextDent 5100 (groups ND, NC and NT, respectively) and Phrozen Sonic Mini 4K (groups PD, PC and PT, respectively). Human gingival fibroblasts were cultured and biocompatibility was evaluated on days 1, 3 and 7. IL-6 and IL-8 concentrations were evaluated at 3 days using ELISA. Surface roughness was evaluated by a contact profilometer. SEM and fluorescence micrographs were analyzed at days 1 and 7. Statistical analyses were performed using SPSS and mean differences were tested using ANOVA and post-hoc Tukey tests (P < .05). RESULTS: There was an increase in cellular viability after 7 days in groups PC and PT, when compared to group PD. ND group resulted in higher concentration of IL-6 when compared to PT group. SEM and fluorescence micrographs showed less adhesion and thinner morphology of fibroblasts from group PD. No significant differences were found regarding surface roughness. CONCLUSION: The use of different printers or resins did not seem to influence surface roughness. NextDent 5100 and Phrozen Sonic Mini 4K produced resins with similar cellular responses in human gingival fibroblasts. However, Denture 3D+ resin resulted in significantly lower biocompatibility, when compared to C&B MFH and Crowntec resins. Further testing is required to support its long-term use, required for complete dentures.

Cell Biological and Antibacterial Evaluation of a New Approach to Zirconia Implant Surfaces Modified with MTA.

Peri-implantitis continues to be one of the major reasons for implant failure. We propose a new approach to the incorporation of MTA into zirconia implant surfaces with Nd:YAG laser and investigate the biological and the microbiological responses of peri-implant cells. Discs of zirconia stabilized with yttria and titanium were produced according to the following four study groups: Nd:YAG laser-textured zirconia coated with MTA (Zr MTA), Nd:YAG laser-textured zirconia (Zr textured), polished zirconia discs, and polished titanium discs (Zr and Ti). Surface roughness was evaluated by contact profilometry. Human osteoblasts (hFOB), gingival fibroblasts (HGF hTERT) and S. oralis were cultured on discs. Cell adhesion and morphology, cell differentiation markers and bacterial growth were evaluated. Zr textured roughness was significantly higher than all other groups. SEM images reveal cellular adhesion at 1 day in all samples in both cell lines. Osteoblasts viability was lower in the Zr MTA group, unlike fibroblasts viability, which was shown to be higher in the Zr MTA group compared with the Zr textured group at 3 and 7 days. Osteocalcin and IL-8 secretion by osteoblasts were higher in Zr MTA. The Zr textured group showed higher IL-8 values released by fibroblasts. No differences in S. oralis CFUs were observed between groups. The present study suggests that zirconia implant surfaces coated with MTA induced fibroblast proliferation and osteoblast differentiation; however, they did not present antibacterial properties.

[Origin and importance of the Latin American Kawasaki Disease Network (REKAMLATINA)]. / Orígenes e importancia de la Red de Enfermedad de Kawasaki en América Latina (REKAMLATINA).

Kawasaki disease is the leading cause of acquired cardiac disease in children. Although the epidemiology of the disease has been well described in Japan, other Asian countries, Europe, Australia and North America, the epidemiology and disease burden in Latin American children is unknown. For this reason, the idea of establishing a research network on Kawasaki disease in children from Latin America was born, becoming this the largest Kawasaki disease international multinational research network and in which 20 countries of the region will be integrated.

Hydrogen Peroxide Diffusion through Dental Tissues-In Vitro Study.

Whitening products commonly utilize hydrogen peroxide (HP) as an active principle, which can penetrate dental tissues with potential side effects due to its low molecular weight. This study aimed to evaluate the HP diffusion of two in-office whitening products, namely 6% VivaStyle Paint On Plus (VS) and Opalescence Boost 40% (OP), in different tooth types. Additionally, the influence of the area of exposure, dental tissue thickness and pulp chamber volume was assessed. Each group consisted of eighteen intact anterior (A), premolar (PM) and molar (M) human teeth, and a positive pulpal pressure model was employed. The samples were analyzed using spectrophotometry, and results were expressed as the mean and 95% confidence interval. Statistical tests and linear regression models were appropriately applied at α = 5%. The total HP (µg) retrieved was as follows: VS-A, 1.333 [1.214, 1.452]; OP-A, 1.538 [1.457, 1.620]; VS-PM, 1.208 [1.123, 1.291]; OP-PM, 3.628 [3.401, 3.855]; VS-M, 2.560 [2.297, 2.823]; and OP-M, 4.197 [3.997, 4.396], with statistically significant differences in diffusion kinetics between whitening products for PM and M. Several HP concentrations attained a minimum cytotoxicity value of 2.22 µg/mL. The regression model shows that OP exposed the pulp chamber to 1.421 µg of HP more than that of VS. Different whitening products can cause cytotoxic HP concentrations in the pulp chamber, with a higher risk observed in molars.

Different Methods for Assessing Tooth Colour-In Vitro Study.

Colour assessment using digital methods can yield varying results, and it is important for clinicians to recognize the potential variability intra and inter-device. This study aimed to compare the L*a*b* values of VITA Classical (VC) and VITA Toothguide 3D-MASTER (VM) guides using two methods, SpectroShade (SS) and eLAB. Thirty-four measurements per tab were performed by a single operator across three batches of each guide. Intraclass correlation coefficients (ICC) between batches were calculated. Values <0.5, 0.5-0.75, 0.75-0.9, and >0.90 were classified as poor, moderate, good, and excellent reliability, respectively. Results were reported as mean and standard deviation of the L*a*b* values and respective colour differences (ΔE00) for each tab and method. Statistical analyses were performed with an independent t-test, α = 0.05. ICC values between batches were excellent for all L*a*b*, except for a* component in eLAB. There were statistically significant differences between methods in most L*a*b* values. The intra-device mean ΔE00 was 0.5 ± 0.6 for VC, 0.5 ± 0.8 for VM in SS, 1.1 ± 0.8 for VC, 1.1 ± 0.9 for VM in eLAB. The mean ΔE00 inter-device was 4.9 ± 1.7 for VC, 5.0 ± 1.7 for VM. Both methods demonstrated good internal consistency, with high ICC values and low intra-device colour differences, but exhibited high variability between methods, higher for a* the component.

Digital full arch implant supported Poly (methyl Methacrylate) interim prosthesis: a practice-based cohort study on survival and quality of life.

PURPOSE: Digitally planned and manufactured PMMA for full arch implant supported immediate loading interim prosthesis are becoming popular comparing with conventional acrylic prosthesis. Studies on prosthodontic performance and patient related outcomes are scarce but needed. The purpose of this study was to evaluate the clinical survival and impact on oral health related quality of life of immediate loading implant supported full arch CAD-CAM milled PMMA interim rehabilitations. METHODS: This was a practice based prospective cohort study performed in a Portuguese dental clinic. Eleven patients received a total of seventeen CAD CAM full implant-supported, screw-retained, full arch rehabilitation with milled PMMA and were followed up for 1 year. Primary outcome was Prosthesis survival determined with a modification of the California Dental Association score and a Kaplan Meyer survival function analysis. Secondary outcome was patient's quality of life as defined by application of the OHIP 14 PT questionnaire and standardized effect size variation between two visits. Significance was set at 5%. RESULTS: Survival probability at 12 months was 76%, complete fracture of the prosthesis occurred in 17,6 % of the cases and small fractures without lab involvement in 5,9%. There was a significant improvement in oral health related quality of life between visit 1 and 4. Mean difference and effect size for total OHIP-14 PT score were -32.91 (± 3.68 SD) and 3.66 (95% CI -1.83 to -5.80) P < 0.001* Wilcoxon matched paired rank test. CONCLUSIONS: Full arch implant supported CAD-CAM milled PMMA interim prosthesis seems a viable approach with good survival rate and great impact on patient's oral health related quality of life.

Bio-Piezoelectric Ceramic Composites for Electroactive Implants-Biological Performance.

Barium titanate (BaTiO3) piezoelectric ceramic may be a potential alternative for promoting osseointegration due to its piezoelectric properties similar to bone electric potentials generated in loading function. In this sense, the aim of this in vitro study was to evaluate the cellular response of human osteoblasts and gingival fibroblasts as well as the impact on S. oralis when in contact with BaTiO3 functionalized zirconia implant surfaces with piezoelectric properties. Zirconia discs with BaTiO3 were produced and contact poling (piezo activation) was performed. Osteoblasts (hFOB 1.19), fibroblasts (HGF hTERT) and S. oralis were culture on discs. Cell viability and morphology, cell differentiation markers, bacterial adhesion and growth were evaluated. The present study suggests that zirconia composite surfaces with the addition of piezoelectric BaTiO3 are not cytotoxic to peri-implant cells. Also, they seem to promote a faster initial osteoblast differentiation. Moreover, these surfaces may inhibit the growth of S. oralis by acting as a bacteriostatic agent over time. Although the piezoelectric properties do not affect the cellular inflammatory profile, they appear to enable the initial adhesion of bacteria, however this is not significant over the entire testing period. Furthermore, the addition of non-poled BaTiO3 to zirconia may have a potential reduction effect on IL-6 mediated-inflammatory activity in fibroblasts.

Cie L*A*B* Values in VITA Classical and VITA 3D Master by Two Dental Spectrophotometers.

PURPOSE: To compare the CIE L*a*b* values of two different dental shade guides using two shade-matching spectrophotometers. MATERIALS AND METHODS: SpectroShade Micro (SS) and Easyshade (ES) (VITA Zahnfabrik) were tested. One calibrated operator performed 30 measurements of each tab from three batches of the two guides, VITA Classical (VC) and VITA 3D Shade Master (VM). Receiver operating characteristic (ROC) curves and intraclass coefficients (ICC) between the different batches were calculated. Results were given as mean and SD of the L*a*b* values and the respective color differences according to the CIEDE 2000 formula (ΔE00) for each of the shade tabs in the two spectrophotometers and then analyzed with independent student t test (α = .05). RESULTS: A total of 1,440 and 2,610 measurements for VC and VM, respectively, were performed per spectrophotometer. There were statistically significant differences between the two devices for all L*a*b* values, with the exception of: L* for 3R1.5; a* for 2R1.5, 3L1.5, 2L2.5, 3M2, 3L2.5, 4L1.5, and 4L2.5; and b* for D3, 1M2, and 3M2. When assessing the same shade guide, differences in ΔE00 were detected between devices above the acceptability threshold (AT) (ΔE00 ≥ 1.8) for all shade tabs except for VC (C1, C2, D3, A3.5, C3, and A4) and VM (4M1, 3R2.5, 4L2.5, and 4M3). The overall mean of the interdevice ΔE00 was 2.2 ± 1.0 for VC and 2.5 ± 1.0 for VM. CONCLUSIONS: The two dental spectrophotometers presented high ICC and ROC values, which validates their indication as auxiliary tools. However, there are discrepancies in the hues D (VC) and R (VM) with interdevice variability when evaluated for the L*a*b* component. Int J Prosthodont 2023;36:e38-e52.

Hydrogen peroxide release kinetics into saliva from different whitening products: a double-blind, randomized clinical trial.

The objective of this study is to compare salivary hydrogen peroxide (HP) release kinetics and potential toxicity of systemic exposure of four different whitening products. A double-blind, randomized controlled trial was conducted in a Portuguese dental faculty clinic. Two hundred forty volunteers were randomized to eight intervention groups. Participants were randomly assigned to receive active or placebo applications of one of four different products: Opalescence 10% PF™ (OPL), Vivastyle® 10%™ (VS10%), Vivadent Paint On Plus™ (PO+), and Trés White Supreme™ (TWS). Saliva collection was obtained by established methods at different times. The HP salivary content was determined by a photometric method. Salivary HP variations, total amount of salivary HP, and counts of subjects above the safe daily HP dose were the main outcome measures. All whitening systems significantly released HP to the saliva when compared to placebo, and all showed different release kinetics. The adaptable tray system (TWS) presented a risk increase of 37% [20-54%, 95% confidence interval] when compared to the other systems. The use of an adaptable tray whitening system with higher concentration of HP increases the toxicity potential.