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Prosthesis discomfort and a lack of skin-like quality is a source of patient dissatisfaction with facial prostheses. To engineer skin-like replacements, knowledge of the differences between facial skin properties and those for prosthetic materials is essential. This project measured six viscoelastic properties (percent laxity, stiffness, elastic deformation, creep, absorbed energy, and percent elasticity) at six facial locations with a suction device in a human adult population equally stratified for age, sex, and race. The same properties were measured for eight facial prosthetic elastomers currently available for clinical usage. The results showed that the prosthetic materials were 1.8 to 6.4 times higher in stiffness, 2 to 4 times lower in absorbed energy, and 2.75 to 9 times lower in viscous creep than facial skin (p < 0.001). Clustering analyses determined that facial skin properties fell into three groups—those associated with body of ear, cheek, and remaining locations. This provides baseline information for designing future replacements for missing facial tissues. more...

PURPOSE The accuracy of digital impressions is still controversial for complete arch implant cases. The aim of this study is to compare the accuracy of different intraoral scanners with the conventional technique in terms of trueness and precision in a complete arch implant model. MATERIAL AND METHODS Eight implants were inserted asymmetrically in a polyurethane edentulous mandibular model with different angulations. A 3-dimensional (3D) reference model was obtained by scanning this polyurethane model with an optical scanner. First, digital impressions were made by using 3 different intraoral scanners: Carestream 3500 (DC), Cerec Omnicam (DO) and 3Shape Trios 3 (DT). Subsequently, a nonsplinted open tray impression technique was used for conventional impression group (C) and then the master casts were digitalized with a lab scanner. Each 10 STL files belonging to 4 different impression groups were imported to a reverse engineering program, to measure distance and angle deviations from the reference model. All statistical analyses were performed after taking absolute values of the data. After comparing the impression groups with one-way ANOVA, the trueness and precision values were analyzed by Tukey post hoc test and 0.05 was used as the level of significance. RESULTS The mean trueness of distance was 123.06 ± 89.83 µm for DC, 229.72 ± 121.34 µm for DO, 209.75 ± 47.07 µm for DT, and 345.32 ± 75.12 µm for C group (p < 0.0001). While DC showed significantly lower deviation compared to DO and C, no significant difference was found between DC and DT. C showed the highest distance deviation significantly in all groups; and no significant difference was found between DO and DT groups. In angle measurements; the trueness was 0.26° ± 0.07° for DC, 0.53° ± 0.42° for DO, 0.33° ± 0.30° for DT, and 0.74° ± 0.65° for C group. There was no significant difference between the groups in terms of angular trueness (p = 0.074). In terms of the precision for distance, the results of DC 80.43 ± 29.69 µm, DO 94.06 ± 69.96 µm, DT 35.55 ± 28.46 µm and C 66.97 ± 36.69 µm were determined (p = 0.036). The significant difference was found only between DT and DO among all groups. Finally, angular precision was determined to be 0.19° ± 0.11° for DC, 0.30° ± 0.28° for DO, 0.22° ± 0.19° for DT, and 0.50° ± 0.38° for Group C. No significant difference was found between the groups, in terms of angular precision (p = 0.053). CONCLUSIONS All digital impression groups yielded superior data compared to conventional technique in terms of trueness. DC formed the impression group with the highest trueness in both distance and angular measurements. The results of this in vitro study suggest the use of intraoral scanners compared to the conventional impression techniques in complete arch implant cases with high angulations. more...

Purpose The purpose of this study was to obtain information about the resident selection and Match process that occurred for the Commission on Dental Accreditation (CODA)-accredited Advanced Education in Prosthodontics program in North America from the program directors' perspective, after the first year of implementation. Materials and methods The list of Advanced Education in Prosthodontics program in CODA-accredited North American institutions was obtained from the ACP central office, and the directors of each program were identified. The surveys were distributed to 48 program directors online and results were compiled. Results Out of 48 programs, 43 directors responded to and completed the survey (90.0%), where 35 programs participated in the Match process, 5 did not, and 3 were omitted due to incomplete surveys. While the majority of programs did not see any changes in their applicant pool or their quality, 10 programs (25.0%) observed a number of increases in the application and 13 programs (32.5%) observed an increase in the quality of the applications. Among the 35 programs that participated in the Match process, the main reasons for their participation were "fairness" (48.2%), "did not want to keep moving up interview dates" (23.2%), and "have applicants come to interview as planned" (21.4%). Thirty-three programs reported that 75% to 100% of the invited applicants came to the interview (76.7%). The majority of programs that participated in Match expressed satisfaction with the process (29/33, 80.6%). Sixteen programs (45.7%) reported that they matched with 100% of their first selections. Conclusion Overall response of reintroduction of the Match process for advanced prosthodontic resident selection was very positive for majority of the program directors. more...

There are several shade matching instruments developed for clinical use, but the validity of their use in dental research has not been thoroughly investigated. The objective of this study is to evaluate the accuracy of using two clinical color measuring instruments, VitaEasyshade and Spectroshade, against a referent laboratory color measuring instrument (Spectroradiometer PR670).The validity and repeatability of the referent laboratory color measuring instrument was assessed using standard color patches with certified CIE L*a*b* values. 10% of the 240 color patches were randomly selected and measured ten times in a random order to test for repeatability. 16 metal ceramic specimens, fabricated from base metal alloy veneered with porcelain of different Vita Classic shades, were measured for L*a*b* values using the PR670, Vita EasyShade and the Spectroshade. The CIE L*a*b* values obtained from the three color measuring instruments were compared using repeated measures ANOVA and post hoc using the Bonferroni test. The color difference, CIEDE2000 (∆EL*a*b* values varied significantly between the three instruments. When comparing the mean ΔEThe lack of clinical significance in values obtained from the SpectroShade when compared to those obtained by the PR670 suggests that the SpectroShade may be recommended for use in dental color research.The SpectroShade instrument and PR670 spectroradiometer provided values that lacked clinical significance, suggesting that its use may be highly beneficial for clinical shade matching as well as color research. more...

The objective was to compare the repeatability between dental faculty, whose clinical practice was primarily restorative dentistry, and final year dental students in categorizing the inherent translucency of images selected at random using either a 3- or 7-point scale (translucent to opaque). Digital images of anterior dentition were randomly selected based on inherent translucency. Thirty images (five were repeated) were randomized and categorized by 20 dental students and 20 faculty on their inherent translucency. Statistical analysis was performed using an F test for analysis of variance at 95% confidence interval. A covariance parameter estimate (CPE) was accomplished to compare the inter-rater variability of the dental faculty and dental students. Statistically, more variability occurred between Slides (CPE of 0.185 (p = 0.001)) and between Subject and Slide (CPE of 0.122 (p = 0.0002)) than within subjects (CPE of 0.021 (p = 0.083)). Viewing repeat Slides, Students (CPE = 0.16) were more consistent (p &lt, 0.05) than faculty (CPE = 1.8) using the 3- point scale, while the CPE was the same (CPE = 0.669) using 7-point scale. Dental students and faculty were consistent using the 7-point scale to judge repeat slides, while dental students in this limited pilot study were more consistent when viewing a repeat slide using the 3-point scale. more...

The aim of this study was to analyze information about advanced education programs in prosthodontics (AEPPs) collected in American Dental Association (ADA) surveys on advanced dental education from 2006-07 to 2016-17. Data recorded included number of AEPPs and information on program directors, applicants, and enrollees in AEPPs. The results showed that, from 2006 to 2016, there was an increase in the number of AEPPs and enrollment of prosthodontic residents, and the number of applicants per program more than doubled. Despite these increases, steps are needed to increase the number of underrepresented minority residents in prosthodontics. Also, a periodic survey of prosthodontic residents to identify their goals, experiences during training, and career plans could benefit the specialty by providing more insight into the future prosthodontic workforce. more...

The effect of a novel nano-ceramic coating (TiO2) using an atomic layer deposition (ALD) technique on the surface of polymethyl methacrylate (PMMA) material was investigated. The patients’ and clinicians’ perception and acceptance of the PMMA color with TiO2 coating were also examined. In vitro color measurement was performed on thirty specimens (light, original, and dark pink) before and after TiO2 coating. Patients’ and clinicians’ perception and acceptance of color changes on PMMA were measured and compared. Descriptive and analytic statistics were analyzed (a = 0.05). TiO2 films were successfully deposited on the PMMA specimen by the ALD technique. Color changes after TiO2 coating were observed on all three PMMA shades, significantly higher than the established 50:50% perceptibility threshold, but below the established 50:50% acceptability threshold. The percentage of patients that perceived a color difference after TiO2 coating were 83.3%, 63.9%, and 77.8% for light, original, and dark pink, respectively. The percentages of clinicians that were satisfied with the color difference were 96.4%, 80%, and 69.2% for light, original, and dark pink, respectively. Color changes after TiO2 coating were observed, but below the acceptable threshold. The clinical survey demonstrated that a color difference was perceived but was clinically acceptable. In general, laypeople have lower perception and higher acceptance of changes in PMMA color than clinicians. more...

This study aimed to investigate and compare the color stability and stainability of computer-aided design/computer-aided manufacturing (CAD/CAM) restorative materials in their glazed (G) and polished (P) state when exposed to cigarette smoke, as well as after brushing. Three CAD/CAM restorative materials were investigated: lithium disilicate CAD (LD), zirconia (Zr), and Telio PMMA CAD (PMMA), according to their surface finishing and assignment to cigarette smoking exposure or soaking in the saliva (control) group. The color change (∆E) was calculated before and after the intervention performed for all specimens, using the L*a*b values to quantitatively assess the shade differences. Statistical analysis was performed using one-way repeated measures ANOVA and Bonferroni multiple comparison analysis (α = 0.05). The surface finishing did not influence the materials’ stainability. Color change was noted after smoking, LD and Zr-G and Zr-P had a comparable color change (p > 0.05), while PMMA presented lower ∆E values (p < 0.05). After brushing, all specimens had a significant color change that was high for LD-G and LD-P, and Zr-G, compared with Zr-P and PMMA (p < 0.05). In conclusion, the exposure to cigarette smoke showed that LD, Zr, and PMMA are all susceptible to staining, but brushing decreases surface staining. more...

Purpose The aim of this systematic review was to evaluate and compare three commonly used proportions that include the golden proportion, golden percentage, and Recurring Esthetic Dental (RED) proportion to identify which of the mathematical formulas, if any, can be used to provide predictable and repeatable esthetic clinical outcomes. Methods A comprehensive search of electronic databases that included EBSCO, ProQuest, SCOPUS, Science Direct, Wiley, Google Scholar and PubMed was conducted using the terms: "golden proportion", "golden percentage", and "Recurring Esthetic Dental (RED) proportions" alone or in concurrence with one or both ensuing terms: "tooth proportions" and "esthetic tooth proportions". In addition, the following journals were hand searched for relevant articles: Journal of Prosthodontics, Journal of Prosthetic Dentistry and Journal of Esthetic and Restorative Dentistry. Related citations were also considered. Results Tooth proportions varied substantially in the natural dentition. No studies revealed findings that supported the use of one mathematical formula to predict esthetic success. The golden proportion is present between the central to lateral incisor in some cases, but rarely between the lateral incisor and the canine. When compared to the other proportions, the golden percentage provided better starting points for tooth shape and size, but only when values were adjusted to consider other factors such as ethnicity and/or facial proportions. Conclusion Mathematical formulas did not provide consistent results that would allow for their use as a standardized guide for esthetically pleasing smiles. Although the golden percentage may be a good starting point if the percentages are adjusted on a case-to-case basis, generalized esthetic ideals cannot be determined by a mathematical formula and are open to interpretation by both the clinician and the patient. This article is protected by copyright. All rights reserved. more...

Limited data, especially in vivo data, exist regarding translucency parameter (TP) values for vital anterior nonrestored dentition. Additionally, published information on the CIELab values of vital enamel at a theoretical infinite thickness is lacking. Obtaining TP and CIELab values in a population that varies in terms of ethnicity, age, and sex would be useful to inform the development and placement of esthetic dental restorations that more accurately capture the complex optical qualities of enamel.The purpose of this clinical study was to investigate in vivo the TP and CIELab values of vital anterior incisor enamel at a theoretical infinite thickness in a diverse pool of participants who varied in age, ethnicity, and sex.Spectral reflectance measurements (380 to 780 nm at 2-nm intervals) of the mid-incisal region of vital, unrestored maxillary anterior teeth were made in 120 participants, equally divided into 2 sexes, 4 racial or ethnic groups, and 5 age ranges. Instruments were oriented to achieve 0-degree observation and 45-degree illumination, and spectral measurements were made with white and black silicone backgrounds. Reflectance spectra of the incisal enamel from both the black and white silicone backing were used to fit to the Kubelka-Munk (K-M) reflectance theory. The CIEDE2000 color difference formula was used to determine TP, and data were compared among participant demographics. CIELab color coordinate values for enamel at an infinite thickness were calculated by using a D65 illumination and CIE standard human (2-degree) observer. To determine value ranges and significant differences among participant groups, CIELab values were analyzed with a 4-way ANOVA, and TP values were analyzed with a generalized linear mixed model. Pairwise comparisons of interest were evaluated with Bonferroni-corrected Student t tests.For maxillary central incisor enamel, the average TP was 10.1 ±3.6, and the average CIELab color coordinates were L∗=73.5 ±7.6, a∗=2.2 ±1.8, b∗=11.9 ±8.4. TP values of incisal enamel significantly differed among specific age and ethnic groups, with general significant interactions of age and sex (P=.009), as well as ethnicity and age (P=.042). CIE color coordinates of enamel at an infinite thickness were found in the L∗ coordinate among different age groups with the same sex and ethnicity, specifically when comparing CIELab direction with the population characteristics of age (P=.011) and the interaction between age, sex, and ethnicity (P=.035).In vivo L∗ values and TP values of incisal enamel differed significantly among groups determined by ethnicity, age, and sex. more...

PURPOSE: The purpose of the study was to assess participants' and presenters' perceptions of a live web-based lecture series in comparison to traditional in-person lectures. MATERIALS AND METHODS: A virtual lecture series was organized by the --- from March 25th until June 3rd of 2020. Twenty-five postgraduate prosthodontics programs and 81 presenters participated. Two surveys were developed and distributed to the audience (N = 330) and the presenters (N = 81). Follow-up emails were sent one week, three weeks, and four weeks after the initial email survey to encourage its completion. The data were analyzed descriptively. One-way ANOVA (p = .05), followed by a post hoc test, was used to compare the response percentages among the different generations of presenters and participants. RESULTS: Fifty-two percent of participants, and 65% of presenters, completed the survey. More than 96% of participants and presenters were satisfied with the lecture series. Seventy-nine percent of audience members felt that the live web-based lectures were as effective as traditional classroom lectures, or more effective; 32% of presenters agreed. Millennial audience members had significantly (p = 0.0028) more negative responses than the other generations. CONCLUSION: Participants have more positive perceptions of web-based lectures than presenters. This article is protected by copyright. All rights reserved. more...

The objective of this study was to assess if the setting expansion, compressive strength, compressive modulus and Knoop hardness is reduced in Type III, IV and V gypsum products when excess water is added to recommended water/powder (W/P) ratios for full-arch implant master casts. Four properties were measured: linear setting expansion, compressive strength, compressive modulus, and Knoop hardness. Three dental stones were evaluated: ISO Type III, Type IV, and Type V. Water was added to recommended W/P ratios as follows: (1) 0%, the manufacturer&rsquo, s recommend W/P ratio, (2) 50%, 1.5 times the manufacturer&rsquo, s recommendation of water, (3) 100%, three times the manufacturer&rsquo, s recommendation of water, (4) 150%, 2.5 times the manufacturer&rsquo, s recommendation of water, and (5) 200%, three times the manufacturer&rsquo, s recommendation of water. For all three gypsum types, 50% water additions minimally affected the setting expansion and compressive modulus (p &gt, 0.05), but lowered compressive strength by 26% to 52% (p &lt, 0.05). Knoop hardness was lowered by 24% and 48% for Types V and III (p &lt, 0.05), whereas Type IV was not significantly affected (p &gt, 0.05). With few exceptions, the physical properties for the three gypsum types reached minimum values at 100% dilution, with few changes noted at higher dilutions. Increased W/P ratios did not adequately reduce the setting expansion and adversely affected other physical properties. Of the gypsums tested, Type IV is still recommended due to its lower setting expansion for full-arch implant master casts. more...

Radiotherapy is being performed in many situations as a curative approach for head and neck cancer instead of surgery due to the current novel coronavirus disease (COVID-19) pandemic. A recent publication reported that even hypofractionation was being conducted in order to reduce the daily exposure of both patients and the medical staff involved in cancer therapies. As a result, dental teams may be requested more frequently than usual to fabricate intraoral stents (IOS). Given that IOS may be a potential source of COVID-19 contagion, the main purpose of the present correspondence is to offer a guide on how health professionals may be safely presented in the room, on the management of the IOS and also how to sanitize the stents. more...

Maxillofacial prosthetics (MFP) programs in the U.S. select only a limited number of applicants for fellowship positions. The aims of this study were to survey MFP fellows about which factors influenced their choice of programs and to survey MFP directors about what they considered critical factors in the selection process. Surveys were sent to all eight directors and 13 fellows at all eight U.S. MFP programs in June 2015. The directors' questions asked about general information, resident selection process, letters of recommendation, interview process, and decision process. The fellows' questions addressed their demographics, program-related factors, and future goals. The directors' surveys were sent directly to the directors, and the fellows' surveys were sent to the directors for distribution. The survey response rate for the directors was 87.5% (N=7), and that of the fellows was 53.8% (N=7). In selecting fellows for programs, responding directors reported the interview process was most important, followed by letters of recommendation, personal statement, and prosthodontic program grades. Responding fellows reported that location, variety of treatment, patient volume provided, and clinical education were crucial components in their choice of program. This information may be useful to MFP programs and fellows in the continuing development of this specialty. more...

PURPOSE In the field of prosthodontics, patients often require complex and extensive restorative care. This can involve the use of dental restorations to restore teeth on both the maxillary and mandibular arch. Current literature has evaluated the wear properties of different dental ceramics against enamel, but studies regarding dental ceramics opposing one another are limited. The purpose of this study was to assess the wear potential and wear behavior of CAD/CAM zirconia (ZR) and lithium disilicate (LD) materials against a similar ceramic material, and how the surface finish of these dental ceramics might affect patterns of wear. MATERIALS AND METHODS Using a sphere-on-plate tribometer system, different surface finishes (glazed-G and glazed then polished-GP) of ZR and LD were evaluated following wear simulation. Artificial saliva of physiologic pH was used as a lubricant during wear simulation at 37°C. The coefficient of friction (COF) was calculated during the wear simulation. After wear simulation was complete, volume loss, surface roughness, and surface characterization of the specimens were analyzed using white-light interferometry and scanning electron microscopy (SEM). Statistical significance between materials and surface finish was established with two-way ANOVA and Bonferroni post hoc test (α = 0.05). RESULTS Based on the 2-way ANOVA, material (p = 0.002) significantly affected the COF. LD showed a higher COF (p = 0.002) than ZR. Material (p < 0.001) and surface finish (p = 0.004) significantly affected the surface roughness inside the scar. ZR had significantly lower surface roughness compared to LD (p < 0.001). For outside scar, surface finish (p < 0.001) significantly affected the surface roughness. Polished specimens showed significantly higher roughness compared to glazed specimens for both inside (p = 0.004) and outside scar (p < 0.001). For volume loss, material (p < 0.001) and the interaction between material and surface finish (p < 0.001) were statistically significant. LD had higher volume loss than ZR (p < 0.001). For both glazed and polished finished, LD-G and LD-GP had significantly higher volume loss than ZR-G (p = 0.028), and ZR-GP (p < 0.001), respectively. SEM analysis indicated particle build-up and a grooving mechanism of wear for the LD-GP specimens. This suggested a three-body wear phenomenon occurring for LD-GP specimens, which was not visible in SEM imaging for other specimen types. CONCLUSIONS This study demonstrated the resistance to wear and low abrasiveness of ZR when compared to LD in a simulated masticatory environment. This can be best explained by the increased strength of ZR, and the introduction of three-body wear to LD specimens from the accumulation of embedded wear debris onto its surface. Wear data and comparison of SEM images following wear simulation confirmed this interpretation. more...

Made available in DSpace on 2022-04-29T08:05:42Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-01-01 Statement of problem Although craniofacial implants have been used for retention of facial prostheses, failures are common. Titanium undergoes corrosion in the oral cavity, but the corrosion of craniofacial implants requires evaluation. Purpose The purpose of this in vitro study was to investigate the corrosion stability of commercially pure titanium (CP Ti) exposed to simulated human perspiration at 2 different pH levels (5.5 and 8). Material and methods Fifteen titanium disks were divided into 3 groups (n=5 per group). The control group was subjected to simulated body fluid (SBF) (control). Disks from the 2 experimental groups were immersed in simulated alkaline perspiration (SAKP) and simulated acidic perspiration (SACP). Electrochemical tests, including open circuit potential (3600 seconds), electrochemical impedance spectroscopy, and potentiodynamic tests were performed according to the standardized method of 3-cell electrodes. Data were analyzed by 1-way ANOVA and the Tukey honestly significant difference tests (α=.05). Results Simulated human perspiration reduced the corrosion stability of CP Ti (P.05) from each other. The increase in capacitance suggests that the acceleration of the ionic exchanges between the CP Ti and the electrolyte leads to a lower corrosion resistance. SAKP reduced the oxide layer resistance of CP Ti (P more...

Purpose To assess the management of sleep apnea and snoring disorders in Advanced Education Programs in Prosthodontics (AEPP) in the United States. Materials and methods A 51 item, online survey was sent to program directors at 48 AEPPs in the United States in 2015. Data results were analyzed descriptively. Results Thirty-five program directors responded to the survey. Twenty-four (68.6%, N = 35) programs report not having a dedicated course for the treatment of sleep apnea and snoring disorders. The majority (94.3%) of programs chose to treat sleep disordered breathing with oral appliance therapy and 80.0% (N = 35) of programs utilize customized sleep apnea oral devices. However, only 48.6% (N = 35) and 51.4% (N = 35) of programs regularly address sleep apnea and snoring disorders at initial examination during the comprehensive exam and medical history questionnaire, respectively. Conclusions The confidence interval for this survey is 8.71 at a confidence level of 95% due to a response rate of 72.9%. This confidence interval suggests there is responder bias in the survey results. Therefore, the results of this survey provide a suggestion of how sleep disorders are managed in AEPPs. Programs appear to be consistent among each other with regards to treatment modalities for sleep disordered breathing. The results suggest that patients are not screened enough to receive treatment addressing sleep disorders. more...

The aim of this study was to determine the difference between the intended education by advanced education in prosthodontics (AEP) program directors and the perceived education received by AEP residents with respect to concepts of esthetic dentistry. Residents' confidence levels and current practices were also determined based on program level, with first- and second-year residents combined into "junior residents" and third- and fourth-year residents combined into "senior residents." Surveys were distributed to all U.S. and Canadian AEP program directors (N=52) in 2014 and residents (N=393) in 2015. The seven questions asked of directors and 20 asked of residents assessed resident training. The response rate for directors was 59.6% and for residents was 27.3%. Statistically significant results were found between the responding program directors' perceived education on esthetic principles and the responding residents' perceived education. The senior-level residents were more confident in each of the categories than residents at the junior level, although the difference was only significant for selecting porcelain systems to match inherent translucency, transfer of information to the laboratory, and surface staining or characterization. There was a difference between the program directors' intended teaching and the residents' perceptions with regards to bleaching, shade matching, selection of porcelain systems, transfer of information to the laboratory, and surface staining or characterization. The residents' confidence levels were higher at the senior level than those at the junior level in selecting porcelain systems, transfer of information to the laboratory, and staining/characterization. Faculty members in advanced prosthodontics programs may be able to use these findings to improve their residents' education in these areas. more...

Objectives To compare the percentage of patients who had an oral cancer examination (OCE) by their primary care provider (PCP) in medical clinics participating in a web-based education with poster reminder intervention to that of patients in control clinics. To also determine the effects for PCPs in medical clinics participating in the web-based education with poster reminder intervention as compared with those in control clinics regarding: a) index of knowledge of oral cancer risk factors (RiskOC) and b) index of knowledge of oral cancer diagnostic procedures (DiagOC). Methods Six medical clinics were recruited to participate in this study and randomly assigned to an intervention group or a control group. PCPs (physicians, physician assistants, and advanced practice registered nurses) took a pretest; 2 weeks later, they participated in the web-based educational program, including a posttest (intervention group) or took a posttest only (control group). In each clinic, 1 week following completion of the PCPs' posttests, 94 patients were recruited to complete a one-page survey. Results The intervention clinics were found to be a significant factor for the PCPs to perform patient OCEs, after controlling for significant covariates, that is, age, main reason for clinic visit, OCE for patient in the past year, clinic's mean DiagOC score, and clinic's mean RiskOC score. The intervention also resulted in the PCPs increasing their pretest to posttest RiskOC scores. Conclusions The use of intervention has the potential to increase PCPs' short-term knowledge and to increase the frequency of PCPs' routine, nonsymptomatic opportunistic OCE on patients. more...

Statement of problem To our knowledge, no data are available on the actual lighting that is used for visual shade matching in private dental offices. Purpose The purpose of this study was to determine the shade matching practices and interest in continuing education in dental practices and to determine the quantity and quality of the ambient lighting used during visual shade matching in a sample cohort of dentists in private practices. Material and methods Thirty-two private practices were enrolled, and each completed a 1-page survey on the clinic’s shade matching practices. A spectrophotometer was used to measure the ambient lighting in each practice, collecting data on color temperature (Kelvin), color rendering index (CRI), and light intensity (foot candles/fc). A 2-sided nonparametric sign test was used to compare the true median color temperature with the standard (5500°K). A 1-sided t test was used to compare the CRI with the standard (CRI >90) (α=.05 for all statistical analyses). Results All dental practitioners surveyed used mainly visual shade matching in their practices. Of those, 87.5% showed interest in attending continuing education on this topic, with 56.3% preferring a clinical demonstration course. The mean color temperature was 4152.9°K and was significantly different from the standard 5500°K ( P t test indicated that the mean CRI was less than 90 ( P =1). The 95% confidence interval for the intensity was 80.7 to 111.6 fc. Conclusions The ambient light in the majority of the 32 dental private practices measured was not ideal for visual shade matching. more...

The aim of this study was to determine the educational methods and tools used to teach tooth prognosis and treatment complexity determination in U.S. predoctoral dental programs. In 2018, an online survey was emailed to the academic deans of all 66 accredited U.S. dental schools. Of these, 42 schools responded (63.6%), and 36 schools completed the entire survey (54.5%). The methods reported for teaching tooth prognosis and case complexity determination varied widely among the participating schools. Among the respondents, 25% reported using the American Association of Endodontists' Endodontic Case Difficulty Assessment, while 10% reported having no specific method for teaching prognosis. The most common method for teaching overall treatment complexity was the Prosthodontic Diagnostic Index, which was used by 24% of the respondents. However, another 24% reported that their school did not have a specific method for teaching treatment complexity. Large percentages of the respondents reported that students sometimes or often made wrong tooth prognosis and case complexity determination (90% and 92%, respectively). The most prominent feedback provided by the respondents based on their experience was the importance of faculty standardization, the understanding of students' inexperience, and the need for an interdisciplinary approach. The majority of these respondents reported that their schools had specific methods of teaching prognosis and case complexity determination. However, there was a wide range of teaching practices related to the contents and levels of evidence. more...

The primary aim of this study was to determine the characteristics that current chairpersons in restorative dentistry, general dentistry, prosthodontics, and operative dentistry departments in U.S. dental schools feel are most relevant in contributing to their success. The secondary aim was to determine these individuals' rankings of the importance of a listed set of characteristics for them to be successful in their position. All 82 current chairs of the specified departments were invited to respond to an electronic survey. The survey first asked respondents to list the five most essential characteristics to serve as chair of a department and to rank those characteristics based on importance. Participants were next given a list of ten characteristics in the categories of management and leadership and, without being aware of the category of each individual item, asked to rank them in terms of importance for their success. A total of 39 chairpersons completed the survey (47.6% response rate; 83.3% male and 16.2% female). In section one, the respondents reported that leadership, vision, work ethic, integrity, communication, and organization were the most essential characteristics for their success. In section two, the respondents ranked the leadership characteristics as statistically more important than the management characteristics (p more...

Statement of problem Partial fixed dental prostheses with a small connector size are required for optimal esthetics and limited interarch space; however, final strength is endangered. Purpose The purpose of this in vitro study was to evaluate the effect of different connector designs on the flexural strength of simulated 3-unit partial fixed dental prostheses made of yttria-stabilized tetragonal zirconia polycrystalline using computer-aided design and computer-aided manufacturing technology. Material and methods To simulate a 3-unit partial fixed dental prosthesis, 20 rectangular bar-shaped specimens were fabricated with dimensions of 4 ±0.05 mm (H)×4 ±0.05 mm (W)×30 0.5 mm (L). Each bar specimen had 2 constricted parts on both sides, representing the connector and defining a central pontic of 10 ±0.10 mm in length. The specimens were divided into 4 groups according to the connector diameter and design, as follows: SR: 2 mm (H)×3 mm (W) round 0.6 mm radius of curvature; SS: 2 mm (H)×3 mm (W) sharp 0.1 mm radius of curvature; CR: 3 mm (H)×3 mm (W) round 0.6 mm radius of curvature; and CS: 3 mm (H)×3 mm (W) sharp 0.1 mm radius of curvature. An additional 5 specimens were fabricated with no constriction and served as the control group. The specimens were subjected to a 3-point flexural strength test in a universal testing machine with a crosshead speed of 0.5 mm/min until failure. Scanning electron microscopic and photomicrograph images were used to examine the fracture surfaces. Two-way ANOVA and the Tukey-Kramer post hoc test were used to analyze the data (α=.05). Results The mean flexural strength for SR 2 mm (H)×3 mm (W) round 0.6 mm radius of curvature (583.6 ±49.7 MPa) was significantly higher than that of SS, which was 2 mm (H)×3 mm (W) sharp 0.1 mm radius of curvature (502.8 ±23.3 MPa). Similarly, the mean flexural strength for CR was 3 mm (H)×3 mm (W) round 0.6 mm radius of curvature (682.9 ±36.8), which was significantly higher than that of CC, 3 mm (H)×3 mm (W) sharp 0.1 mm radius of curvature (486.7 ±35.6 MPa). Conclusions The flexural strength of the yttria-stabilized tetragonal zirconia polycrystalline-based ceramics was affected by the connector dimension and design. The 2-round connector design was more able to withstand occlusal forces than the sharp design. The 3-connector design with a minimum cross section of 2×3 mm is recommended for anterior fixed dental prostheses, provided it has a round curvature. more...

The color stability and staining of acrylic resin denture teeth remains an esthetic problem for complete denture wearers.The purpose of this study was to evaluate the long-term clinical color stability and stainability of acrylic resin denture teeth in complete denture wearers over a period of 5 years.Fifty participants rehabilitated with complete dentures from February 2008 to December 2013 were selected. The demographic data and the clinical characteristics of participants were recorded. Color change (ΔE) in 3 regions of the denture teeth (incisal, middle, and cervical) was evaluated by spectrophotometry in the CIE L*a*b* system. Participants were asked whether they had noticed any changes in the coloring of the teeth in their dentures. Hierarchical clustering analysis was used to identify groups formed from variables related to demographic questions and color analysis. Two-way ANOVA among the color cluster groups was performed and the Tukey-Kramer test was used as a post hoc test (α=.05). A chi-square test and Fisher exact test were used to identify the association between the study variables and color changes in the participants' responses (α=.05).Four cluster groups from 50 participants were identified in the clustering analysis. The ΔE was statistically significant for the interaction between the dental third and cluster groups (P.001). Cluster groups 1 and 4 exhibited statistically higher ΔE values than cluster groups 2 and 3 (P.05). Greater chromatic alterations were noted in the incisal third of the teeth than in the cervical and medium thirds in the cluster groups 1 (ΔE=11.03 ±1.22) and 3 (ΔE=4.14 ±1.14) (P.05). No relationship was found with the participants' personal opinions about color change (P.05).Although the acrylic resin denture teeth exhibited color instability and staining in vivo, the participants were unable to identify the color change. The cluster groups with higher color change values consumed more staining solutions. more...

The aims of this study were to measure the research productivity of directors of U.S. advanced education in prosthodontics programs (AEPP) and to identify associations between the directors' publication metrics and professional characteristics. A list of AEPP directors was obtained from the American College of Prosthodontists website in December 2015. Information on gender, academic rank, and highest degree was collected from the institutional website for each individual. Citation databases (Scopus and Google Scholar) were searched for each director's h-index and i10-index (both indexes are based on numbers of citations of the author's articles) and total numbers of publications and citations. The search identified 50 AEPP directors. The majority were male and had a primary appointment at a university. Most held the rank of associate professor or professor and held both DDS and MS degrees. The mean h-index and i10-index of all directors were 6.32±6.97 and 6.84±10.77, respectively. Their mean numbers of publications and citations were 24.60±31.21 and 288.40±625.97, respectively. The analysis showed that the program directors affiliated with a university had significantly higher mean values for all indexes than those of non-university-affiliated program directors. Professors had productivity metrics significantly higher than those of other ranks in all measures of research productivity. more...

Patients at risk of developing oral and/or oropharyngeal cancer (OPC) are more likely to see primary care providers (PCPs) than a dentist. Many PCPs do not regularly perform oral cancer examination (OCE). The purpose of this study was to design a web-based educational program based on a behavioral framework to encourage PCPs to conduct OCE. PCPs were solicited to provide feedback on the program and to evaluate their short-term knowledge. The integrated behavioral model was used to design the program. Fifteen PCPs (five in each group: physicians, physician assistants, and nurse practitioners) reviewed the program and took a posttest: (1) index of knowledge of risk factors for oral cancer (RiskOC) and (2) index of knowledge of diagnostic procedures for oral cancer (DiagOC). Findings from the process evaluation were mainly positive, with comments on the length of the program comprising the ten negative comments. No significant difference among groups of PCPs (physicians, physician assistants, and nurse practitioners) was detected for DiagOC (p = 0.43) or RiskOC (p = 0.201). A program on OPC for PCPs should be less than 40 min. Postviewing knowledge outcomes were similar for all PCPs. The web-based program on OPC based on a behavioral framework could have similar short-term knowledge outcomes for all PCPs and may increase the number of PCPs performing OCEs. more...

In the field of prosthodontics, patients often require complex and extensive restorative care. This can involve the use of dental restorations to restore teeth on both the maxillary and mandibular arch. Current literature has evaluated the wear properties of different dental ceramics against enamel, but studies regarding dental ceramics opposing one another are limited. The purpose of this study was to assess the wear potential and wear behavior of CAD/CAM zirconia (ZR) and lithium disilicate (LD) materials against a similar ceramic material, and how the surface finish of these dental ceramics might affect patterns of wear.Using a sphere-on-plate tribometer system, different surface finishes (glazed-G and glazed then polished-GP) of ZR and LD were evaluated following wear simulation. Artificial saliva of physiologic pH was used as a lubricant during wear simulation at 37°C. The coefficient of friction (COF) was calculated during the wear simulation. After wear simulation was complete, volume loss, surface roughness, and surface characterization of the specimens were analyzed using white-light interferometry and scanning electron microscopy (SEM). Statistical significance between materials and surface finish was established with two-way ANOVA and Bonferroni post hoc test (α = 0.05).Based on the 2-way ANOVA, material (p = 0.002) significantly affected the COF. LD showed a higher COF (p = 0.002) than ZR. Material (p0.001) and surface finish (p = 0.004) significantly affected the surface roughness inside the scar. ZR had significantly lower surface roughness compared to LD (p0.001). For outside scar, surface finish (p0.001) significantly affected the surface roughness. Polished specimens showed significantly higher roughness compared to glazed specimens for both inside (p = 0.004) and outside scar (p0.001). For volume loss, material (p0.001) and the interaction between material and surface finish (p0.001) were statistically significant. LD had higher volume loss than ZR (p0.001). For both glazed and polished finished, LD-G and LD-GP had significantly higher volume loss than ZR-G (p = 0.028), and ZR-GP (p0.001), respectively. SEM analysis indicated particle build-up and a grooving mechanism of wear for the LD-GP specimens. This suggested a three-body wear phenomenon occurring for LD-GP specimens, which was not visible in SEM imaging for other specimen types.This study demonstrated the resistance to wear and low abrasiveness of ZR when compared to LD in a simulated masticatory environment. This can be best explained by the increased strength of ZR, and the introduction of three-body wear to LD specimens from the accumulation of embedded wear debris onto its surface. Wear data and comparison of SEM images following wear simulation confirmed this interpretation. more...

Statement of problem Maxillofacial prostheses made of silicone elastomers undergo undesirable color degradation over time. How this color change can be prevented is unclear. Purpose The purpose of this in vitro study was to evaluate the ability of an oxide nanocoating to prevent color degradation of maxillofacial silicone elastomers after artificial accelerated aging. Material and methods A silicone elastomer with functional intrinsic pigment was tested. Specimens (N=20) were fabricated, and half of them were coated with a nanolayer of titanium dioxide (TiO2) using atomic layer deposition. Both coated and noncoated specimens (control) were exposed to artificial aging at 450 kJ/m2 of total energy. Changes in the color of all the specimens with and without TiO2 nanocoating were measured before and after the atomic layer deposition coating and before and after aging. The obtained color data were analyzed by using independent t tests and the 1-sample t test (α=.05). Results Color change (ΔE1=3.4 ±1.4) was observed for the silicone elastomers after the specimens were surface coated with TiO2 nanofilm, although this change was not statistically significant (P=.369) compared with the acceptability threshold (ΔE=3.0). Upon exposure to artificial aging, the noncoated control specimens underwent color change (ΔE2=2.5 ±0.7, P=.083 compared with the acceptability threshold). The specimens with TiO2 nanocoated surface experienced the least color change (ΔE3=1.4 ±0.6) when subjected to artificial aging, and this change was significantly lower (P Conclusions TiO2 nanocoating was shown to be effective in reducing color degradation of the silicone elastomer exposed to artificial aging for 120 hours with 450 kJ/m2 of total energy. more...

Statement of problem Which impression material, impression tray type, and implant impression technique combination produces the most accurate complete-arch impression is unclear. Purpose The purpose of this in vitro study was to compare the implant impression accuracy of a completely edentulous arch made with addition silicone occlusal registration material and an open tray with the implant impression accuracy of other conventional impression techniques. Material and methods A master cast was fabricated from Type IV gypsum with four 3.8-mm diameter implants with internal hexagon located in the area of mandibular canines and first molars. Impressions (N=60) were made from the master cast using the 6 techniques investigated: group B-OC-N with occlusal registration impression material (B), open custom tray (OC), and nonsplinted impression pins (N); group B-OS-N with occlusal registration impression material (B), open plastic perforated stock tray (OS), and nonsplinted impression pins (N); group PE-OC-N with polyether medium-body impression material (PE), open custom tray (OC), and nonsplinted impression pins (N); group PE-OC-S with polyether medium-body impression material (PE), open custom tray (OC), and impression pins splinted (S) with autopolymerizing resin cut after 17 minutes and reconnected; group PE-CC-N with polyether medium-body impression material (PE), closed custom tray (CC), and nonsplinted impression pins (N); group PVS-CS-N with simultaneous double-mix polyvinyl siloxane impression material (PVS), closed stock perforated metal tray (CS), and nonsplinted impression pins (N). Type IV gypsum casts were fabricated 24 hours after making the impressions. A computerized numerical control 3D coordinate measuring machine was used to measure the absolute differences of the distances between the centroids of the 4 implants among the casts produced and the distances measured at the master cast. The Kruskal-Wallis test was used to determine differences among the experimental groups (α=.05). The Mann-Whitney U post hoc analysis was used for all group combinations. Results No significant differences were found between the test groups B-OC-N and PE-OC-S, which were more accurate than the other groups. Group B-OS-N resulted in the least accurate impressions of all experimental groups. Group PE-OC-S resulted in more accurate impressions than the PE-OC-N group. No statistically significant differences were found between groups PE-OC-N and PE-CC-N or between groups PVS-CS-N and PE-CC-N. Conclusions For complete edentulism, the use of silicone occlusal registration material with an open custom tray and nonsplinted impression pins resulted in impressions as accurate as those produced with PE open custom tray with splinted impression pins. These 2 techniques resulted in more accurate impressions than the other 4 techniques studied. more...

Made available in DSpace on 2018-12-11T17:09:37Z (GMT). No. of bitstreams: 0 Previous issue date: 2017-08-01 Statement of problem The longevity of silicone facial prostheses is short, and published data concerning this type of rehabilitation are limited. Purpose The purpose of this retrospective study was to identify predictive variables for prosthetic failure and to highlight the results that can be expected after treatment with silicone facial prostheses. Material and methods After institutional approval, patient records from a single Brazilian institution for the time period 2004 to 2015 were assessed. A standardized form was used to collect patient data. Frailty survival modeling (simple random effects survival model) was used to test whether age, sex, type of prosthesis, source of defect, number of implants, and type of retention have a direct impact on the prosthetic failure rate (α=.05). Results Auricular prostheses were the most frequently fabricated prostheses. Eighty-four prostheses were fabricated during the follow-up period. The overall survival rate for facial prostheses was 34.5%. Color alteration was the most common reason for new prostheses (27.38%). The implant success rate was 98.18%. The number of implants approached statistical significance (P=.06) with a reduced risk of failure when the patient had 2 implants compared with patients with zero implants and patients with more than 2 implants. Conclusions Patients should be recalled frequently so that retouches can be performed, avoiding the repeated fabrication of new prostheses. Well-designed studies are necessary to identify more relevant complications and factors that lead to prosthetic failure. Coordinator Dental Oncology Service Institute of Cancer of São Paulo (ICESP) São Paulo Brazil; and Coordinator Anaplastology Service of Brånemark Institute Assistant Dental Oncology Service Institute of Cancer of São Paulo São Paulo (ICESP) Doctoral student Department of Dental Materials and Prosthodontics Aracatuba Dental School Sao Paulo State University (UNESP) Assistant Dental Oncology Service Institute of Cancer of São Paulo (ICESP) Professor Department of Traumatology and Bucomaxillofacial Surgery University of Sagrado Coração (USC) Surgery Service of Brånermark Institute Department of Stomatology School of Dentistry University of Sao Paulo (USP) Director Center of Oral Health Research School of Dentistry Academic Partners Center for Promoting Health and Health Equality Creighton University Assistant Professor Oral Diagnosis Department Piracicaba Dental School University of Campinas (UNICAMP) Assistant Professor Department of Prosthodontics and Periodontology University of Campinas (UNICAMP) Piracicaba Dental School Section head Maxillofacial Prosthodontics Veteran's Affairs Nebraska-Western Iowa Health Care System Doctoral student Department of Dental Materials and Prosthodontics Aracatuba Dental School Sao Paulo State University (UNESP) more...

Purpose The purpose of this study was to evaluate the effect of race, age, and gender on Commision Internationale de l’Eclairage Lab color space (CIELAB) values of attached gingival colors. The color coordinates of an optimal proposed attached gingival shade guide were also determined. Material and Methods Participants (n = 120) were recruited to fulfill the following stratification of five age groups: 18-29, 30-39, 40-49, 50-59, and 60-85, with four racial categories (white, black, Asian, and others) and balanced for gender. Reflectance measurements of participants’ attached gingiva were made using a spectroradiometer and Xenon arc lamp with a 45/0 optical configuration. A stepwise discriminant analysis was carried out to identify gingival color contribution from race, age, and gender. A hierarchical clustering analysis was used to identify color groups that clustered together. The coverage error of the proposed shade guide was calculated to the original gingival color. Results The stepwise discriminant analysis showed a statistically significant difference in gingival color contribution from the factors evaluated. Significant influence was found for the race/gender factors (p < 0.05), but not for age. The cluster analysis results revealed three cluster centroids with mean L*a*b* as follows: (1 = 51.0 ± 4.2, 27.7 ± 4.7, 18.3 ± 3.2), (2 = 61.4 ± 4.5, 24.3 ± 4.3, 17.6 ± 2.3), and (3 = 36.1 ± 4.1, 21 ± 4.9, 16 ± 5.2). The coverage errors to the following racial categories were: Asian (ΔE = 6.0 ± 4.8), black (ΔE = 6.7 ± 3.9), others (ΔE = 5.8 ± 2.9), and white (ΔE = 4.6 ± 2.7). Conclusions The study showed that L*a*b* was significantly affected by race and gender. Clustering analysis was able to identify clusters in 120 participants for three gingival tones. more...

It is unknown if present-day pigments used for intrinsic colouration of maxillofacial prostheses are representative of human facial skin tones. This study's purpose was to measure L*a*b* values of pigmented elastomers coloured by eleven skin tone pigments and determine coverage error (CE) when the pigments were compared to human facial lip and nose colour data.11 skin tone pigments were combined at 0.1%, 1% and 10% by weight with A-2186 elastomer (n=3). L*a*b* values were measured with a spectrophotometer and group means were used to calculate ΔE* colour differences with each L*a*b* value obtained for human nose and lip. Pigmented elastomer CEs were calculated for nose and lip. Results were compared to CEs for proposed shade guide colours obtained from clustering analyses of facial skin colours.L* values of pigmented elastomers generally were higher than those measured for nose and lip, whereas a* values were lower. CEs for pigmented elastomers were higher than those obtained from the proposed shade guide obtained from clustered skin measurements.Overall, the current commercial elastomers appeared to be too white and not red enough to adequately match the skin tones of the subject population. Adjustments must be made to the existing pigmenting system in order to adequately match the skin colours of the study population.The creation of a shade guide and a collection of intrinsic pigments representing the realm of human facial skin colours would greatly decrease the time a patient must sit while the clinician is obtaining an acceptable colour match for the silicone to be used for processing the final prosthesis, thereby increasing both patient satisfaction and clinician productivity. more...

A benefit of a nylon partial removable dental prosthesis (PRDP) is the absence of a metal framework, providing improved esthetics. Unfortunately, the lack of a traditional framework reduces rigidity and the support of occlusal rests. This clinical report describes a combination of a nylon PRDP (polyamide denture base resin) and a traditional PRDP (framework/resin) for a Kennedy Class II, Modification 1, partially edentulous mandible. more...

Statement of problem The motivation of maxillofacial prosthodontists to go into fellowship training and specific procedures in maxillofacial prosthetics practice once they have completed training has not been previously evaluated. Purpose The purpose of this study was to survey maxillofacial prosthodontists in the United States to investigate their reasons for pursuing maxillofacial prosthetic training and their practice profiles. Material and methods In June 2015, a survey was sent to all US maxillofacial prosthodontists asking for descriptive demographics, their reasoning as to what prompted entrance into a maxillofacial prosthetic program, and their practice pattern. Frequencies, percentages, means, and standard deviations were calculated and reported. Results The survey response rate was 60.4%. The main reason for pursuing maxillofacial training was primarily personal satisfaction, prosthodontic residency exposure, and mentorship rather than media exposure and compensation. The time spent in prosthodontic practice varied among practitioners, with the majority of practice time spent accomplishing standard prosthodontic procedures (65.59%) versus maxillofacial (25.53%) or surgical procedures (9.67%). Of 12 clinical maxillofacial procedures inquired about, the most prevalent were obturators, dental oncology, and mandibular resections. Conclusions This study reveals that personal satisfaction, mentorship, and prosthodontic residency exposure were the reasons most prosthodontists pursued an additional year of maxillofacial prosthetic fellowship. Most were very satisfied with their training and chosen career path and would recommend an additional year of training. The majority of maxillofacial prosthodontists provided maxillofacial prosthetic treatment for approximately one fourth of their practice time. The most common procedures performed were obturators, dental oncology, and mandibular resections. more...

Statement of problem The effects of toothbrushing (B) and thermocycling (TC) on the surface texture of different materials with various fabrication processes have been investigated. However, studies of computer-aided design and computer-aided manufacturing (CAD-CAM) ceramic restorations are limited. Purpose The purpose of this in vitro study was to evaluate the effect of B and TC on the color stability and surface roughness of extrinsically characterized and glazed CAD-CAM ceramic restorations. Material and methods Lithium disilicate CAD ceramic (n=90) and zirconia ceramic (n=90) were studied. All specimens were crystallized/sintered, characterized, and glazed following the manufacturer's recommendation. The specimens were divided into 9 different groups: B, TC, and a combination of B plus TC (B+TC). Brushing was performed at 50 000, 100 000, and 150 000 cycles, simulating an oral environment of 5, 10, and 15 years. Thermocycling was performed at 6000, 12 000, and 18 000 cycles, simulating an oral environment of 5, 10, and 15 years. Brushing plus TC was performed with the combination of the 50 000 cycles of B, then 6000 cycles of TC, and 10 000 cycles of B, then 12 000 cycles of TC, and 15 000 cycles of B, then 18 000 cycles of TC. The color and surface roughness of each specimen were measured before and after all interventions with simulated cycles. Color differences (ΔE) and surface roughness (ΔR a ) data were analyzed using 2-way ANOVA, followed by the least significant difference test (α=.05). The correlation between ΔE and ΔR a was statistically analyzed using the Pearson correlation analysis. Results Within the lithium disilicate CAD groups, intervention did not result in any significant differences in color change ( P >.05). Within the zirconia groups, a 15-year clinical simulation revealed significantly higher ΔE values than a simulated 5-year exposure ( P =.017). Increased simulated cycles showed significantly higher R a values for all groups. Within the zirconia groups, B revealed significantly smoother surfaces than TC ( P P a values than the groups of B+TC for 5 years ( P P =.003). No correlation (lithium disilicate CAD, r=.079; P =.462; zirconia, r=.001; P =.989) was found between the color change and surface roughness. Conclusions For both lithium disilicate CAD and zirconia, color changes were below the selected clinical perceptible threshold (ΔE=2.6) after all intervention and simulated cycles. All mean surface roughness measurements were below 0.2 μm. Generally, the surface of both lithium disilicate CAD and zirconia became rougher. No correlation was found between color difference and surface roughness for either material. more...

Introduction: Understanding the distribution of incisal translucency will provide clinicians a guide to use this knowledge to improve the esthetic replication of anterior restorations.The aim of this study is to investigate the distribution of incisal translucency of unrestored vital natural maxillary central, lateral, and canine vital teeth from a stratified population in different age, gender, and race. Materials and Methods: A total of 120 subjects were recruited for this study. Six subjects with equal gender balance from four racial/ethnic groups (White, Black, Asian, and others) were recruited from each of the following age groups: 18 to 29 years, 30 to 39 years, 40 to 49 years, 50 to 59 years, and 60 to 85 years. Potential subjects were clinically screened to determine if three specific anterior teeth (maxillary central incisor, lateral incisor, and canine) were non-restored, natural permanent teeth free from external staining or bleaching. A digital imaging and shade analysis device was used to measure tooth translucency. Results: Statistically significant interaction (p more...

Objectives: Oral health has a significant effect on health, and for women, poor oral health can lead to poor birth outcomes and can affect their child's health. Nursing interventions to improve the oral health of at-risk women have the potential to increase maternal and child systemic and oral health. The identification of women at a high risk for poor oral health is a necessary to develop and evaluate these interventions. Design and Sample: This study examined the factors related to dental insurance and dental service use for women of childbearing age in the United States. A secondary analysis of the 2003–2004 National Health and Nutrition Examination Survey was completed to examine the predisposing, enabling, and need variables associated with dental insurance status and dental service use in a representative random sample of 1,071 women. Results: The results showed that over 40% of women had no dental insurance. Women with less education, lower income, and dental need were significantly less likely to have dental insurance. Dental utilization by the uninsured was low and a racial/ethnic disparity was noted. Conclusion: A lack of dental insurance and dental service utilization is a significant concern. Nurses working with low-income women should educate the population about oral health and advocate for policies to increase dental insurance coverage. more...

Functional rehabilitation of fully edentulous maxillary defects is always regarded as a prosthodontic challenge. Surgical augmentation does not always offer value addition in the functional treatment outcome. This article describes the maxillofacial prosthodontic treatment of an edentulous patient who received an abdominus microvascular free flap surgical augmentation of a large acquired maxillary defect. more...

Although a large body of scientific literature shows that background color and luminance affect color perception, previous measurements of tooth color difference thresholds have not taken the effects of viewing context into account. The present study tested the hypothesis that differences in skin/gingival color influence individuals’ judgments of tooth color differences. Perceptibility and acceptability thresholds were determined in 10 individuals using a signal detection paradigm. They evaluated 500 pseudo-random presentations of two facial portraits: an African-American and a Caucasian. These portraits varied trial-to-trial only in the direction (CIELAB +L*, +a*, or +b*) or magnitude of the color difference between a portrait’s two central incisors. The individuals were significantly less sensitive to tooth color differences in the +L* direction in the Caucasian portrait than for any other combination of color direction or portrait type. Furthermore, comparable perceptibility and acceptability thresholds were generally not statistically significant from each other. more...

Despite the reported effects of smokeless tobacco (ST) on the periodontium and high prevalence of ST use in rural populations and in men, studies on this specific topic are limited. The purpose of this cross-sectional investigation is to evaluate the periodontal health status of male ST users from a rural population.Adult male residents of two rural Appalachian Ohio counties and daily ST users, with a unilateral mandibular oral ST keratosis lesion, were recruited. Subjects completed a questionnaire and received oral examination. Teeth present, ST keratosis lesion, plaque and gingival index, probing depth (PD), recession depth (RD), and attachment level were recorded. Statistical analysis compared ST-site mandibular teeth (teeth adjacent to the subject's unilateral ST keratosis lesion) to NST-site teeth (contralateral corresponding teeth).This study includes 73 ST users. Recession prevalence is much greater in ST-site quadrants (36%) compared to NST-site quadrants (18%; P0.001). Twice as many teeth had recession on ST-site (approximately 20%) than NST-site (approximately 10%; P = 0.0001). Average buccal RD on ST-site teeth did not differ from that on the NST-site teeth (P = 0.0875). Although average buccal attachment loss is greater on ST-site teeth (P = 0.016), the mean difference is0.5 mm. When stratified by years of ST use, subjects using ST for 10 to 18 years exhibit the most differences between ST and NST sites, whereas subjects using ST for10 years show no differences.The results indicate that greater gingival recession prevalence and extent are associated with ST placement site in rural male ST users. more...

It remains unclear which gingival shade guide is most effective in producing the best visual shade match.The purpose of this study was to determine and compare the coverage errors (CEs) of 2 different gingival shade guides and their combination in a selected population.The CEs of the following gingival shade guides were evaluated: (1) Lucitone 199, (2) IPS Gingiva, and (3) a combination of the 2 shade guide systems. The spectral reflectance values of the center of each gingival shade tab (1.5 mm in diameter) were measured (without a backing) with a spectroradiometer and an external light source at wavelengths from 380 nm to 780 nm at 2-nm intervals. All spectral reflectance measurements were made using 0-degree observer and 45-degree illumination and then converted to CIE values. The attached gingiva of 120 subjects was measured with the same protocol. The CEs of each of the 120 subjects' attached gingiva for each of the 2 shade guide systems and their combination were determined and averaged. The mean minimum CEs were analyzed with repeated measures ANOVA and the post hoc Tukey HSD for multiple comparison (alpha=.05).A significant difference (P.001) was found among the mean minimum CEs of the 2 gingival shade guide systems and their combination. The Tukey HSD test revealed that the mean minimum CEs for Lucitone 199 (Delta E 10.8 +/-4.4) were significantly different from the IPS Gingiva (Delta E 8.6 +/-3.6) shade guide system. However, the combination of the 2 gingival shade guide systems (Delta E 7.9 +/-3.4) was not significantly different from the IPS Gingiva system, but a significant difference was found among races (P=.016). No interactions were found between the other tested groups. The mean CE for white individuals (Delta E 8.3 +/-2.5) is significantly different and less than the mean CE for African Americans (Delta E 10.0 +/-4.4). The CEs for Asians (Delta E=9.1 +/-4.3) and others (Delta E 9.0 +/-4.4) are not significantly different from CEs for whites or African Americans.The IPS Gingiva shade guide system resulted in the lowest CEs compared to the Lucitone 199 shade guide system. The mean CE for Lucitone 199 was significantly greater than the mean CE for IPS Gingiva and for the combination of the 2 guides. The mean CE for whites is significantly different and less than the mean CE for African Americans. The CEs for Asians and others are not significantly different from CEs for whites or African Americans. more...

Statement of problem There is no scientific information regarding the selection of the color of teeth for edentulous patients. Purpose The purpose of this study was to evaluate linear regression models that may be used to predict color parameters for central incisors of edentulous patients based on some characteristics of dentate subjects. Material and methods A spectroradiometer and an external light source were set in a noncontacting 45/0 degree (45-degree illumination and 0-degree observer) optical configuration to measure the color of subjects' vital craniofacial structures (maxillary central incisor, attached gingiva, and facial skin). The subjects (n=120) were stratified into 5 age groups with 4 racial groups and balanced for gender. Linear first-order regression was used to determine the significant factors (α=.05) in the prediction model for each color direction of the color of the maxillary central incisor. Age, gender, and color of the other craniofacial structures were studied as potential predictors. Final predictions in each color direction were based only on the statistically significant factors, and then the color differences between observed and predicted CIELAB values for the central incisors were calculated and summarized. Results The statistically significant predictors of age and gender accounted for 36% of the total variability in L*. The statistically significant predictor of age accounted for 16% of the total variability in a*. The statistically significant predictors of age and gender accounted for 21% of the variability in b*. The mean Δ (SD) between predicted and observed CIELAB values for the central incisor was 5.8 (3.2). Conclusions Age and gender were found to be statistically significant determinants in predicting the natural color of central incisors. Although the precision of these predictions was less than the median color difference found for all pairs of teeth studied, and may be considered an acceptable precision, further study is needed to reduce this precision to the limit of detection. (J Prosthet Dent 2008;100:93-98) more...

Functional rehabilitation of a completely edentulous patient with removable prostheses is a clinical challenge. A patient with an edentulous maxilla and mandible received 6 endosseous implants in the maxilla and 5 implants in the mandible using CAD/CAM surgical templates. Definitive maxillary and mandibular implant-supported fixed complete dentures were connected immediately after implant placement using a CAD/CAM-guided implant surgical placement protocol. (J Prosthet Dent 2008;99:416-420) more...