Evolution of Aesthetic Dentistry.

One of the main goals of dental treatment is to mimic teeth and design smiles in a most natural and aesthetic manner, based on the individual and specific needs of the patient. Possibilities to reach that goal have significantly improved over the last decade through new and specific treatment modalities, steadily enhanced and more aesthetic dental materials, and novel techniques and technologies. This article gives an overview of the evolution of aesthetic dentistry over the past 100 y from a historical point of view and highlights advances in the development of dental research and clinical interventions that have contributed the science and art of aesthetic dentistry. Among the most noteworthy advancements over the past decade are the establishment of universal aesthetic rules and guidelines based on the assessment of natural aesthetic parameters, anatomy, and physiognomy; the development of tooth whitening and advanced restorative as well as prosthetic materials and techniques, supported by the pioneering discovery of dental adhesion; the significant progress in orthodontics and periodontal as well as oral and maxillofacial surgery; and, most recently, the implementation of digital technologies in the 3-dimensional planning and realization of truly natural, individual, and aesthetic smiles. In the future, artificial intelligence and machine learning will likely lead to automation of aesthetic evaluation, smile design, and treatment-planning processes.

Eighteen-month Clinical Study of Universal Adhesives in Noncarious Cervical Lesions.

OBJECTIVE: To evaluate the clinical performance of Scotchbond Universal (3M Oral Care) and Prime & Bond Elect (Dentsply Sirona) in the restoration of noncarious cervical lesions (NCCLs). METHODS AND MATERIALS: This was a randomized controlled clinical trial involving 63 subjects. Two hundred and three NCCLs were restored using Scotchbond Universal and Prime & Bond Elect using both an etch-and-rinse and a self-etch technique. Lesions were notch-shaped NCCLs, and the restorations were placed without any mechanical retention. Restorations were finished immediately after placement and scored with regard to retention, marginal discoloration, marginal adaptation, and secondary caries. Similar assessment of the restorations was performed 18 months after placement. Logistic regression was performed for each outcome separately with a compound symmetric variance-covariance structure assumed to consider a correlation of restorations within subjects. All analyses were conducted using SAS version 9.4 (SAS Inc). RESULTS: One hundred and fifty-eight teeth (77.8% of the restorations placed) in 46 subjects (73% of subjects enrolled) were available for the 18-month follow-up. A statistically significant difference was reached only for the comparison Scotchbond Universal/self-etch (SU_SE) and Prime & Bond Elect/etch-and-rinse (PBE_E&R) groups ( p=0.01), where a restoration with SU_SE was 66% less likely to maintain a score of Alpha for marginal discoloration than a restoration performed with PBE_E&R. CONCLUSIONS: Scotchbond Universal and Prime & Bond Elect presented acceptable clinical performance after 18 months of clinical service. However, Scotchbond Universal, when applied with a self-etch approach, did demonstrate a relatively high level of marginal discoloration when compared to the other groups.

Barrel maturation, oak alternatives and micro-oxygenation: influence on red wine aging and quality.

The impact of micro-oxygenation (MOX) in conjunction with a variety of oak alternatives on phenolic composition and red wine aging was investigated and compared with traditional barrel aging. Although several studies concluded that MOX give similar results to barrel aging, few have compared them directly and none directly compared MOX with and without wood alternatives and barrel aging. Results confirmed that MOX had a positive effect on colour density, even after 5 months of bottle aging. This is supported by an increase in polymeric phenol and pigment content not only with aging but in the MOX compared to barrel matured wine treatments. Descriptive analysis showed that MOX in combination with wood alternatives such as oak chips and staves could mimic short term (six months) barrel aging in new American and French oak barrels in regards to sensory characteristics.

Beer consumers' perceptions of the health aspects of alcoholic beverages.

Consumers' perceptions about alcohol are shaped by numerous factors. This environment includes advertisements, public service announcements, product labels, various health claims, and warnings about the dangers of alcohol consumption. This study used focus groups and questionnaires to examine consumers' perceptions of alcoholic beverages based on their nutritional value and health benefits. The overall purpose of this study was to examine beer consumers' perceptions of the health attributes and content of alcoholic beverages. Volunteers were surveyed at large commercial breweries in California, Missouri, and New Hampshire. The anonymous, written survey was presented in a self-explanatory format and was completed in 5 to 10 min. The content and style of the survey were derived from focus groups conducted in California. The data are separated by location, gender, and over or under the age of 30. Parametric data on beverage rating were analyzed using analysis of variance (ANOVA) while the nonparametric data from True/False or Yes/No questions were analyzed using chi-square. Although statistically significant variances did exist between survey location, gender, and age, general trends emerged in areas of inquiry. The findings indicate that a great opportunity exists to inform consumers about the health benefits derived from the moderate consumption of all alcoholic beverages.

Beer and wine consumers' perceptions of the nutritional value of alcoholic and nonalcoholic beverages.

In general beer has not been portrayed as part of a balanced diet. However, red wine has been promoted as a beneficial part of a nutritious diet. The evidence is that beer is at least the equal of wine from a nutritional perspective and in countering ailments such as coronary heart disease. This study used surveys to compare beer and wine consumers' perceptions of alcoholic and nonalcoholic beverages. The consumers ranked 7 beverages based upon perceived healthfulness both before and after they were exposed to nutritional information about the beverages. The ranked data were analyzed using analysis of variance. The variance due to the 3-way interaction of place of recruitment, beverage, and ranking was found to be significant at P < 0.05. There was no significant difference between genders. Overall, consumers of alcoholic beverages perceived red wine to be more healthful than the other 6 beverages, including beer and white wine. The perceived healthfulness of a beverage does not appear to be the main factor driving the choice of beverage. Nutritional information does impact consumers' perceptions of the healthfulness of beverages. Consumers who are predominately beer drinkers were more heavily influenced by nutritional information than consumers who were predominately wine drinkers.

Pork quality attributes associated with bilateral carcass variation.

The objective of this study was to identify bilateral differences in pork carcass quality as influenced by single leg shackling and suspension of electrically stunned pigs. Fifty-six Genepacker x EB market barrows (118 kg) were rendered unconscious and insensible to pain via electrical stimulation. Pigs were then shackled and suspended by the right hind leg before exsanguination and remained suspended until scalding. Initial (45-min) pH values of the LM at the 10th to 11th rib interface were different (P = 0.016); shackled side loins possessed a greater i.m. pH than those loins associated with the free side of the carcass (6.26 vs. 6.10). At 24 h postmortem, loins from the shackled side had lower (P < 0.001) L* values than loins from the free side in both the sirloin (53.08 vs. 57.61) and blade (54.61 vs. 57.09) regions. Additionally, b* values were greater (P < 0.001) for loins from the shackled side than loins from the free side in the center (13.81 vs. 13.01) and blade (14.72 vs. 13.68) regions, and in the blade region, a* values were greater (P < 0.001) in the LM from the shackled side than loins from the free side (7.37 vs. 6.26). Moreover, LM chops of loins from the shackled side that were aged 21 d were rated less (P < 0.05) tough (2.74 vs. 3.95) and more (P < 0.05) juicy (4.24 vs. 3.19) than chops from the free-hanging side. However, these differences were not evident after 41 d aging. From the results of this study, it can be concluded that bilateral differences exist within the LM of a pork carcass and that these differences are likely associated with the single-leg shackling and suspension of electrically stunned pigs.

Tooth whitening products and the risk of oral cancer.

Tooth whitening products (TWP) containing hydrogen peroxide (HPO) or carbamide peroxide (CPO) were evaluated in relation to potential oral cancer risk from their use. HPO is genotoxic in vitro, but such activity is not expressed in vivo. The genotoxic risk of HPO exposure of the oral mucosa encountered from TWP use is likely therefore to be vanishingly small. Available animal data on the carcinogenicity of HPO are of limited relevance to risk assessment of oral hazard of HPO exposure from TWP, and where relevant, do not indicate that there is an increased oral cancer risk for people using TWP. Clinical data on HPO-containing TWP only show evidence of mild, transient gingival irritation and tooth sensitivity, with no evidence for the development of preneoplastic or neoplastic oral lesions. Exposures to HPO received by the oral cavity, including areas commonly associated with oral cancer, are exceedingly low and do not plausibly pose a risk for the promotion of initiated cells or for induction of co-carcinogenic effects in conjunction with cigarette smoke or alcohol. The use of TWP was concluded not to pose an increased risk for oral cancer in alcohol abusers and/or heavy cigarette smokers. Furthermore, TWP were concluded to be safe for use by all members of the population, including potential accidental use by children.

Therapy with gentamicin-PMMA beads, gentamicin-collagen sponge, and cefazolin for experimental osteomyelitis due to Staphylococcus aureus in rats.

INTRODUCTION: In spite of new surgical techniques and recently developed antibiotics, there is no satisfactory solution for the treatment of chronic posttraumatic osteomyelitis. The introduction of local antibiotic treatment with gentamicin-PMMA beads according to Klemm has provided new stimuli for the treatment of chronic osteomyelitis. With the development of collagen as an absorbable carrier substance, the disadvantages of the rigid carrier system became evident. Due to the varying surgical techniques and different forms of adjuvant therapy, it is difficult to assess therapeutic methods and compare different studies. Therefore, it seemed appropriate to study the effect of local treatment with different antibiotic carriers in the setting of an animal study. MATERIALS AND METHODS: The proven rat model for Staphylococcus aureus-induced osteomyelitis was used to compare the results of monotherapy with cefazolin, gentamicin-PMMA beads, or gentamicin-containing collagen sponge with the combination of local and systemic antibiotic treatment. RESULTS: Single-agent therapy with parenterally administered cefazolin reduced the CFU from 3.7 x 10(6) to 2.9 x 10(4) g(-1) of tibial bone. The effect on osteomyelitis was more pronounced with the local application of antibiotics. The best results were achieved with the gentamicin-containing collagen sponge which reduced the bacterial colony count to 1.4 x 10(2) CFU/g compared with 9.8 x 10(2) CFU/g achieved with gentamicin-PMMA beads. The effect was most marked using a 4-week combination therapy with local application of the gentamicin-containing collagen sponge and systemic administration of cefazolin. In 9 of 11 animals, no bacteria could be detected in the bone. CONCLUSION: Each of the treatment modalities resulted in a significant therapeutic effect. Due to its ability to quickly release large amounts of gentamicin, the flexible gentamicin-containing collagen sponge proved to be superior to the rigid PMMA system. Although the gentamicin-containing collagen sponge provided high antibiotic concentration at the site of implantation, an additive effect was attained when combined with systemic antibiotic treatment.

Tooth whitening: facts and fallacies.

Since the introduction of nightguard vital bleaching (tray bleaching) in 1989, dentistry has witnessed an astronomical rise in the interest in tooth whitening.(1) As a result, the most frequently asked question is, 'what bleaching technique works best?' Virtually all of today's whitening approaches work, because bleach is bleach. Whether a nightguard bleach is used with only 10% carbamide peroxide (which contains only 3% hydrogen peroxide), over-the-counter (OTC) whitening strips are applied containing 6% hydrogen peroxide, or an in-office bleach is employed using 25-35% hydrogen peroxide, the end results can potentially be the same. Similarity of results is possible because the mechanism of action is the same: oxidation of organic pigments or chromogens in the tooth. Granted, some bleaching approaches are more expeditious than others, owing to differences in concentration or exposure time. But as just noted, the most important factors in the efficacy of any bleaching treatment are concentration of the bleaching agent and duration of the exposure time.

Pork loin color relative to sensory and instrumental tenderness and consumer acceptance.

Pork loin color categories were established with the intent of demonstrating differences in eating quality between them. Center-cut boneless pork loins (n=64) were divided into three color classifications. Category A included National Pork Producers Council color standards 1 and 2; category B, 3 and 4; and category C, 5 and 6. L* means for categories A, B, and C were 57.00, 50.24, and 45.54, respectively. Warner-Bratzler shear force values were not affected by category (P>0.05), but were negatively correlated with a* and b* values (P<0.05). The "in-home" portion of this study consisted of 47 households that prepared and evaluated chops randomly distributed by category. Consumers reported differences in liking of juiciness and liking of tenderness (P<0.05) due to color category. Eighty-nine percent of the households participated in a simulated retail display where, 20.8% chose chops from category A, 26.4% from category B, and 52.8% from category C. A trained panel evaluated the cooked chops and perceived category C to be more tender, more juicy, and less dry than both A and B (P<0.05). Consumers responded similarly to the trained panel in their perceptions of tenderness and juiciness.

Clinical evaluation of two one-bottle dentin adhesives at three years.

BACKGROUND: The method currently used to adhere resin to dentin involves etching, priming and bonding. Many commercial adhesives now combine priming and bonding functions in a single solution, and these are frequently called one-bottle adhesives. The purpose of this study was to compare the 36-month clinical performance of two commercial one-bottle adhesives. METHODS: The authors enrolled 33 patients with noncarious cervical lesions in the study. A total of 101 lesions were restored with either a filled, ethanol-based adhesive (OptiBond Solo, SDS Kerr) or an unfilled, acetone-based adhesive (Prime & Bond 2.1, Dentsply Caulk) and a hybrid resin-based composite. Enamel margins were not beveled, and no mechanical retention was placed. The restorations were evaluated at baseline and six months, 18 months and 36 months after placement using modified Cvar/Ryge criteria. RESULTS: The retention rates at 36 months were 93.3 percent for the ethanol-based adhesive and 89.4 percent for the acetone-based adhesive. The difference in retention rates was not statistically significant. In both groups, 12 percent of the retained restorations had marginal staining, but no recurrent caries was detected around any restoration. Other restoration characteristics such as marginal adaptation and color match remained excellent three years after placement. CONCLUSIONS: The performance of both adhesives was excellent during this 36-month clinical trial. At the most recent recall evaluation (that is, 36 months), the filled, ethanol-based adhesive exhibited slightly better bond durability, but the difference between the two materials was not statistically significant. CLINICAL IMPLICATIONS: The one-bottle adhesives evaluated in this study provided excellent clinical retention of Class V restorations without mechanical retention. When the materials are used properly, restorations are retained at a high rate during at least three years of clinical service.

Eighteen-month clinical evaluation of a filled and unfilled dentin adhesive.

OBJECTIVE: The purpose of this study was to evaluate the performance of a filled (OptiBond Solo) and an unfilled (Prime & Bond 2.1) "one-bottle" adhesive in Class V restorations after 18 months of clinical service. METHODS: Thirty-three patients with non-carious cervical lesions were enrolled in the study. A total of 101 lesions were restored using one of the adhesives and a hybrid composite resin. Enamel was not beveled, nor was any mechanical retention placed. The restorations were evaluated at baseline, and at 6 and 18 months after placement using modified USPHS criteria. RESULTS: Cumulative 18-month retention rates were 93.6% for OptiBond Solo and 98.0% for Prime & Bond 2.1. The difference in retention rates was not statistically significant. For OptiBond Solo, the only notable problems were interfacial staining and marginal adaptation, both of which were less than ideal in 9% of restorations. Marginal problems were slightly less frequent for Prime & Bond 2.1 restorations, but the difference was not significant. CONCLUSIONS: Both adhesives provided Class V retention rates exceeding the 18-month, full acceptance guidelines set by the American Dental Association. Any additional benefit provided by the use of a filled adhesive was not detected in this 18-month clinical trial.

Effect of milk fat, cocoa butter, and whey protein fat replacers on the sensory properties of lowfat and nonfat chocolate ice cream.

Lowfat and nonfat chocolate ice creams were made with 2.5% of milk fat, cocoa butter, or one of two whey protein-based fat replacers, Dairy Lo or Simplesse. Polydextrose was added as required so that all formulations contained the same amount of total solids. Ice cream was stored at a control temperature of-30 degrees C. Hardness, viscosity, and melting rate were measured by physical methods. Trained panelists conducted descriptive sensory analyses of the samples at 0, 6, and 12 wk. Attribute ratings were analyzed by analysis o variance with least significant difference mean separation and orthogonal contrasting. Data were also analyzed by multivariate analysis of variance with canonical variate analysis. Consumer acceptance (n = 50) did not differ among the fresh ice creams (wk 0). Ice cream containing milk fat had less intense cocoa flavor and was more resistant to textural changes over time compared with the other ice creams. Simplesse was more similar to milk fat than was Dairy Lo in its effect on brown color, cocoa flavor, cocoa character, and textural stability but was less similar in terms of thickness and mouthcoating.

Effect of conditioner and restorative resin on enamel bond strengths.

PURPOSE: To evaluate the effect of three enamel conditioners and four restorative materials on enamel shear bond strengths. MATERIALS AND METHODS: 120 bovine incisors were polished to 600-grit and randomly assigned to three enamel adhesive systems (n=40): Syntac Single Component with phosphoric acid etching (PA-SSC), Syntac Single Component without phosphoric acid etching (SSC), and Experimental Prompt L-Pop (LPI), a self-etching adhesive. The specimens were restored with one of four resin restorative materials (n=10): (1) Compoglass F, a high-viscosity compomer; (2) Compoglass Flow, a low-viscosity compomer; (3) Tetric Ceram, a high-viscosity resin-based composite (RBC); and (4) Tetric Flow, a low-viscosity RBC. After thermocycling, shear tests were carried out with an Instron Universal Testing Machine. Mean enamel bond strengths were analyzed with ANOVA and Duncan post hoc test at P < or = 0.05. RESULTS: PA-SSC resulted in higher mean bond strengths than LP1, but the difference was not statistically significant. Both PA-SSC and LP1 resulted in statistically higher mean bond strengths than SSC at P < or = 0.0001. The lowest mean bond strengths of all the groups were obtained when SSC was used with an RBC (Tetric Ceram or Tetric Flow). SSC and PA-SSC resulted in statistically higher mean bond strengths when used with a compomer than when used with an RBC, regardless of the viscosity. Although recommended to be used only with compomers, LP1 resulted in statistically similar enamel bond strengths when used with the composite of corresponding viscosity (Tetric Ceram vs. Compoglass F; Tetric Flow vs. Compoglass Flow). LP1, however, resulted in higher enamel bond strengths when combined with Tetric Ceram than when combined with Tetric Flow. When the results were pooled for "viscosity", high-viscosity restorative materials resulted in higher bond strengths than low-viscosity materials at P < or = 0.041. When the data were pooled for "restorative material", compomers resulted in higher bond strengths than composites at P < or = 0.0001.

Shear bond strengths of one-bottle adhesives to oil-contaminated enamel.

PURPOSE: To evaluate resin bond strength to enamel contaminated with handpiece oil. MATERIALS AND METHODS: Bovine teeth were randomly assigned to six groups of 20 teeth each for treatment with one of six different bonding systems (five one-bottle and one multibottle). For each system, 10 enamel specimens were contaminated with handpiece oil before acid-etching and 10 were contaminated after acid-etching. The enamel was etched for 15 seconds using 35% phosphoric acid. Following adhesive application, composite resin was bonded using a gelatin capsule technique. Shear bond strengths from the two contaminated groups were compared to bond strengths to uncontaminated enamel obtained from a previous study that was performed by the same group of investigators, using the same facility, materials, and methods. RESULTS: Two-way analysis of variance (ANOVA) showed that the factor "surface contamination" did not have a significant effect on bond strength (p > .542). The type of adhesive and the interaction of adhesive and surface contamination were significant (p < .0001 and p < .003, respectively). When oil was applied before etching, mean bond strengths ranged from 18.0 +/- 4.8 MPa for OptiBond SOLO (Kerr Corp., Orange, California) to 25.3 +/- 5.6 MPa for Tenure Quik with Fluoride (Den-Mat Corp., Santa Maria, California). With oil applied after etching, bond strengths ranged from 18.4 +/- 8.0 MPa for Tenure Quik with Fluoride to 27.4 +/- 5.4 MPa for Single Bond (3M Dental Products, St. Paul, Minnesota). For the same adhesive, comparing uncontaminated and "oil-before-etch" contaminated groups, the only statistically significant difference in bond strengths was for OptiBond SOLO: 21.8 +/- 4.0 MPa (uncontaminated) versus 18.0 +/- 4.8 MPa (oil before etch). Comparing uncontaminated and "oil-after-etch" groups, the only statistically significant difference was for Tenure: 24.5 +/- 5.7 MPa (uncontaminated) and 18.4 +/- 8.0 MPa (oil after etch).

Effects of different re-wetting techniques on dentin shear bond strengths.

PURPOSE: For contemporary hydrophilic resin adhesive systems, bonding to dentin is improved if the substrate is maintained in a hydrated state following acid-etching. The purpose of this study was to compare the dentin shear bond strengths of two single-bottle adhesives (one acetone-based and one ethanol-based) applied under different etched-dentin conditions: dry, wet, or dry and re-wetted with different solutions. MATERIALS AND METHODS: Bovine incisors (N = 120) were mounted in acrylic, polished to 600-grit, and randomly assigned to 12 groups (n = 10). Dentin was etched for 15 seconds using 35% phosphoric acid, rinsed, and either blot-dried, air-dried, or air-dried and re-wetted with different solutions (distilled water, Gluma Desensitizer, Aqua-Prep, and 5% glutaraldehyde in water). Two adhesives (Single Bond and Prime & Bond NT) were applied to each of the surface conditions following manufacturers' instructions. After adhesive application and curing, composite was applied in a No. 5 gelatin capsule and light-cured. Specimens were loaded in shear, using an Instron at 5 mm per minute. Shear bond strengths were calculated by dividing the failure load by the bonded surface area. Data were subjected to analysis of variance (ANOVA) and a post hoc Tukey test. RESULTS: Mean shear bond strengths ranged from 12.5 to 26.6 MPa for Single Bond and from 5.6 to 14.7 MPa for Prime & Bond NT. Significant differences were found in both groups of materials (p < .001). The three highest mean bond strengths were obtained (in order) on dentin that was re-wetted with Gluma Desensitizer, re-wetted with Aqua-Prep, or never dried. Differences between these surface conditions were not statistically significant for either material.