Xerostomia in 75-85-year-olds: A longitudinal population study.

BACKGROUND: Xerostomia can pose significant problems for many elderly people. OBJECTIVES: To investigate longitudinal changes in prevalence, persistence, progression, remission and incidence of xerostomia from age 75 to 85 years. METHODS: All 75-year-olds (born 1932) from two Swedish counties, Sweden were mailed a questionnaire in 2007 (N = 5195), and again in 2017 when they were aged 85 (N = 3323). The total response rates at ages 75 and 85 years were 71.9% and 60.8%, respectively. A 'panel', those who participated in both surveys, comprised 1701 individuals (response rate 51.2%). RESULTS: At age 85, there was almost a doubling of self-reported 'yes often' xerostomia compared with age 75 (from 6.2% to 11.3%) and was almost twice as common in women than men (p < .001). When combining 'yes often'/'yes sometimes', xerostomia increased from 33.4% to 49.0%, and was more so among women (p < .001). Xerostomia was commoner at night than daytime, with 23.4% reporting 'yes often' night-time xerostomia at 85 compared with 18.5% at 75, and was also higher in women (p < .001). Progression rates for daytime and night-time xerostomia were 34.2% and 38.1%, for persistence 67.4% and 68.6%, and for remission 24.4% and 16.5%. Average yearly incidence was higher in women than men for both daytime (3.6% vs. 3.2%) and night-time (3.9% vs. 3.7%). Regression analyses predicted protective factors for developing xerostomia reported at age 75 as good general and oral health, absence of medications/intraoral symptom/s, good chewing function and social interaction. CONCLUSIONS: Xerostomia increases markedly from age 75 to 85 years.

Satisfaction with dental appearance in two cohorts of 75-year-olds examined in 2007 and 2017: A repeated cross-sectional study.

BACKGROUND: Satisfaction with dental appearance plays an important role in the self-esteem and psychological well-being of the elderly, the significance of which the attending dentist may not always be fully cognisant of. OBJECTIVES: To assess the level of satisfaction with dental appearance, its associated factors and temporal changes in two cohorts of 75-year-old Swedes born 10 years apart. METHODS: In 2007, a questionnaire was mailed to all those living in Örebro and Östergötland counties, Sweden, who were born in 1932 (n = 5195), and in 2017 to all born in 1942 (n = 7204). The evaluation was carried out with a global question 'Are you satisfied with the appearance of your teeth?', and four attitude-related statements about dental appearance. RESULTS: About 80% in both cohorts were 'very satisfied' or 'to large extent satisfied' with their dental appearance. The 1932 cohort was significantly more concerned about their dental appearance than the 1942 cohort, and women were generally also significantly more concerned than men. In the regression analysis, 'very satisfied' with dental appearance was predicted by good chewing efficiency, having complete dentures, no impact from Oral Impacts on Daily Performance, disagreement that 'minor esthetic imperfections of the teeth have no importance, only they should function well', better perceived general health than same-aged peers and belonging to the 1932 cohort. CONCLUSION: Satisfaction with dental appearance among 75-year-olds was generally high, with attitudes varying by gender and temporally. Women and the earlier-born generation (1932) were more concerned about dental appearance than men and the later-born generation (1942), respectively.

Oral health practices and self-reported adverse effects of E-cigarette use among dental students in 11 countries: an online survey.

OBJECTIVES: E-cigarette use has become popular, particularly among the youth. Its use is associated with harmful general and oral health consequences. This survey aimed to assess self-reported oral hygiene practices, oral and general health events, and changes in physiological functions (including physical status, smell, taste, breathing, appetite, etc.) due to E-cigarette use among dental students. METHODS: This online, multicounty survey involved undergraduate dental students from 20 dental schools across 11 different countries. The questionnaire included demographic characteristics, E-cigarette practices, self-reported complaints, and associated physiological changes due to E-cigarette smoking. Data were descriptively presented as frequencies and percentages. A Chi-square test was used to assess the potential associations between the study group and sub-groups with the different factors. Statistical analysis was performed using SPSS at P < 0.05. RESULTS: Most respondents reported regular brushing of their teeth, whereas only 70% used additional oral hygiene aids. Reported frequencies of complaints ranged from as low as 3.3% for tongue inflammation to as high as 53.3% for headache, with significant differences between E-cigarette users and non-users. Compared to non-smokers, E-cigarette users reported significantly higher prevalence of dry mouth (33.1% vs. 23.4%; P < 0.001), black tongue (5.9% vs. 2.8%; P = 0.002), and heart palpitation (26.3%% vs. 22.8%; P = 0.001). Although two-thirds of the sample reported no change in their physiological functions, E-cigarette users reported significant improvement in their physiological functions compared to never smokers or tobacco users. CONCLUSION: Dental students showed good oral hygiene practices, but E-cigarette users showed a higher prevalence of health complications.

Marginal Integrity of CAD/CAM Ceramic Crowns Using Two Different Finish Line Designs.

OBJECTIVE: Research on evaluation of crowns made by the latest contemporary dental computer-aided design/computer-aided manufacturing (CAD/CAM) systems for their marginal adaptation is scarce. The purpose of this in vitro study was to evaluate the marginal integrity of crowns fabricated by the latest Chairside Economical Restorations of Esthetic Ceramic (CEREC) system using 2 different finish line preparation designs: chamfer and shoulder. MATERIALS AND METHODS: Typodont teeth were divided equally into 2 groups, A and B. The teeth were prepared for full coverage crowns with a shoulder (group A) and chamfer (group B) finish line design. An experienced prosthodontist prepared all crown preparations. Evaluation of 6 sites per sample was completed by 2 calibrated, experienced prosthodontists using the modified US Public Health Services (USPHS) criteria. The descriptive statistics and Z-test were used to evaluate the results. RESULTS: A total of 180 teeth were included in the study (90 teeth in each group). Only 2 crowns in group A and 1 crown in group B were clinically unacceptable. There was no statistical significance (p = 0.282) between the 2 groups regarding finish line design. CONCLUSIONS: The CEREC system provides clinically acceptable crowns and can safely be utilized in dental treatment. Therefore, CAD/CAM restorations could be considered as a safe treatment modality by dental professionals.

Evaluation of a Technique for Reducing Chairside Occlusal Adjustment of Crowns.

PURPOSE: To assess whether the occlusion of metal-ceramic crowns, as received from the laboratory, and the time taken to adjust the occlusion of crowns not deemed acceptable, can be reduced by fabricating the crowns with controlled amounts of infra-occlusion during the laboratory phase. MATERIAL AND METHODS: An opposing set of typodonts, articulated in maximum intercuspal position served as the patient in an in vitro simulation. Seventy-five metal-ceramic crowns were fabricated for the mandibular right second molar with three different occlusal contact specifications: A, control group had occlusal contacts shared evenly by the crown and the neighboring teeth (n = 25); B, first experimental group had the occlusion relieved until 2 shimstock foils were able to be pulled from between the crown and the opposing tooth without tugging (n = 25); C, second experimental group had the occlusion relieved until 4 shimstock foils were able to be pulled from between the crown and the opposing tooth without tugging (n = 25). The occlusion of each crown, as received from the laboratory, was assessed using one of three categories (Excellent, Acceptable, and Poor). Chi-square analysis was used to test the differences in occlusal outcomes between the three study groups. For all of those rated "Acceptable," the time taken to adjust each crown to proper occlusion was recorded. One-way analysis of variance (ANOVA) and Bonferroni tests were carried out to compare the adjustment times across the three study groups. RESULTS: The 2-shim group had the best outcome, with 56% of the crowns rated as "Excellent" (p = 0.001). In addition, there were statistically significant differences in adjustment times between the control group (A) and the 2-shim (B) and the 4-shim (C) groups (p = 0.0001), but not between the 2-shim (B) and 4-shim (C) groups (p = 0.08). CONCLUSIONS: Metal-ceramic crowns fabricated with controlled interocclusal relief of 2- and 4-shims each required less time for chairside occlusal adjustment than crowns fabricated in the laboratory to conventional occlusal contact. However, the overall superior outcome, in terms of the possibility for immediate insertion as received from the laboratory as well as favorable chairside adjustment time, for the 2-shim prespacing suggests that this dimension is the preferred option over 4-shim prespacing to reduce occlusal inaccuracies of indirect restorations.

Changes in conditions related to reported oral and general health over a ten-year period as reflected in two cohorts of 75-year-old subjects examined in 2007 and 2017.

BACKGROUND: The rapidly ageing and increasingly dentate population puts great demands on society regarding the provision of adequate medical and dental care facilities. OBJECTIVES: To present changes in reported demographic, general and oral health factors in two cohorts of 75 year olds in 2007 and 2017, and to analyse factors associated with self-reported number of remaining teeth and chewing efficiency. MATERIAL AND METHODS: All 75-year-old people living in two Swedish counties received a questionnaire in 2007 and in 2017. The response rates in 2007 and in 2017 were 71.9% (n = 3735) and 70.7% (n = 5091), respectively. Reported number of teeth was clinically validated in a selected subgroup. RESULTS: The 2017 cohort reported significantly better general health and dental state. Edentulousness was 7.8% in 2007 and 2.3% in 2017, while 'very good' chewing efficiency was 55.2% and 60.5%, respectively. Born outside Sweden, single living, not feeling healthy and smoking predicted reduced number of teeth in both cohorts. Impaired chewing efficiency in both cohorts was predicted by being born outside Sweden, lower education, not feeling healthy, reduced number of teeth and denture wearing. CONCLUSIONS: Seventy-five-year-old people in Sweden reported much better oral and general health in 2017 compared to 2007. In 2017, 75% had practically all natural teeth present and only 2% were edentulous. This development of an increasingly dentate and partially dentate ageing population will put high demands on the oral healthcare system and will need adapting undergraduate/postgraduate education and management strategies to meet the requirements of the elderly.

Impact of Removable Partial Dental Prostheses on the Oral Health-Related Quality of Life of a South African Cohort with Varied Distributions of Missing Posterior Teeth.

PURPOSE: To determine the impact of removable partial dental prostheses on satisfying the daily functioning and quality of life (QoL) of adult patients with different distributions of missing posterior teeth. MATERIALS AND METHODS: A cross-sectional interventional study was carried out on 80 patients having variously distributed posteriorly shortened and interrupted arches. Treatment comprised provision of partial dentures by senior dental students, supervised by senior clinical teachers who had knowledge of the potential benefits of the shortened dental arch (SDA) concept. The Oral Impacts on Daily Performance Index was completed before and 6 months after prosthetic treatment across groups comprising Kennedy Classes I, II, and III arches. Analysis included descriptive statistics and associations and comparisons between variables. RESULTS: Mean age of patients was 57.4 years (SD = 13.1), many were retired (72.2%), and a majority were females (60%). Most patients lived in urban areas (95%), and were largely unemployed (63.3%). At pretreatment, only 31.3% of patients reported having good dental health and satisfaction with their current oral state, while 82.5% said they had a great need for treatment. The negative oral impacts that were most frequently experienced were those of eating (67.5%), smiling (50%), and being emotionally disturbed (63.8%). Post-treatment, 76.3% indicated good oral health and satisfaction with no significant differences between the 3 Kennedy groups. Any further negative impacts were reported mostly for Kennedy Classes I and II. CONCLUSIONS: Overall, significant reductions of negative impacts were observed following treatment with dentures, across the 3 Kennedy groups, with respect to improved function, satisfaction, and oral health-related QoL. The findings confirm the reliance by partially dentate patients in all 3 Kennedy groups on dentures for improved oral health, although the possible benefits of the SDA concept as an alternative treatment option was not specifically explored.

Attitudes of dentists toward denture adhesives: A questionnaire survey in Greece.

STATEMENT OF PROBLEM: The attitudes of dental professionals toward denture adhesives (DAs) require further investigation. PURPOSE: The purpose of this survey was to assess the attitudes of dentists in Greece toward DAs and the possible effects of sex, age, training, and awareness level on these attitudes. MATERIAL AND METHODS: An 18-item questionnaire in the Greek language concerning the use of DAs by dentists in the metropolitan area of Athens, Greece was distributed on line. Its URL address was emailed to 793 randomly chosen dentists in the area, 438 of whom filled out and submitted a valid questionnaire (55.2% response rate). Data for each item were statistically analyzed for their associations with sex, age, training, and awareness level by the chi-square test for independence (α=.05). RESULTS: The results showed that 61.5% of general practitioners and 49% of specialist prosthodontists recommend the use of DAs. Their continuous use was recommended most frequently (46.9%), mainly in the cream form (93.8%). Their use was recommended not only for patients wearing older dentures (60.2%) but also for patients with newly fabricated ones (61.9%) to assist their adaptation to dentures (42.2%). Associations were found between a few only items and sex (Q07, Q11a,b), age (Q13), training (Q11q,b), and awareness level (Q11a,b,d,e) (P<.05). CONCLUSIONS: This survey shows that in the metropolitan area of Athens, Greece, a significant proportion of dentists (60.3%) recommend the use of DAs and do so more often as a continuous regimen for both existing and new denture wearers. Sex, age, training, and awareness level proved to be factors affecting only a few dentists' attitudes.

Dental erosion in groups of Yemeni children and adolescents and the modification of an erosion partial recording system.

BACKGROUND: The prevalence of dental erosion is rising especially among children and adolescents and its grading needs further investigation. AIMS: To determine the prevalence and severity of dental erosion in groups of Yemeni children and adolescents, and to clinically compare an erosion partial recording system (EPRS) with a proposed modified-simplified version (EPRS-M). DESIGN: Of 6163 individuals aged 5-6, 13-14 and 18-19 years, 911 were randomly selected, of which 668 participated in the study. Dental erosion was graded using EPRS. EPRS-M was proposed, and its sensitivity and specificity was calculated in relation to EPRS. RESULTS: Prevalence of erosion extending into dentine on at least one tooth was 6.8% among 5- to 6-year-olds, 3.0% among 13- to 14-year-olds and 14.6% among 18- to 19-year olds. The highest prevalence was 19.2% among girls aged 18-19 years which was significantly higher than boys (10.4%) in the same age group (P = 0.044). Sensitivity and specificity for EPRS-M in relation to EPRS were 85.7% and 100% for primary teeth, and 84.1% and 100% for permanent teeth. CONCLUSIONS: Dental erosion was common among children and older teenagers and highest among older girls but less common among younger teenagers. The tested accuracy of EPRS-M qualifies it to be used as an initial quick detection tool in future dental erosion research.

Awareness and knowledge of dental erosion among Yemeni dental professionals and students.

BACKGROUND: This study explored Yemeni dentists' and dental students' knowledge about the associated factors, approaches to diagnosis and preventive methods of dental erosion (DE), as well as any associations between DE awareness and some potentially related variables. METHODS: A self-administered questionnaire was distributed to general dental practitioners (n = 323) in Sanaa and to fifth year dental students (n = 97) at the University of Science and Technology, Sanaa, Yemen during the period from July to November 2013. Descriptive and logistic regression analyses were conducted. RESULTS: Overall response rate was 79 %. Results indicated that 61 % of respondents learned about DE from dental school, 27 % from their own studies and the rest from continuing education courses and the media. DE was reportedly most frequently seen on incisors by 46 % of respondents and on premolars and molars by 24 %. While 48 % reported DE to be more common in male patients, no gender differences were reported by 20 % of respondents. Acidic drinks were believed to be causative factors for DE by 41 % of dentists and 52 % of students, while 90 % of respondents believed that patients' dietary history is important during DE diagnosis. As preventive measures for DE, reduction of acidic drink consumption was advised by 51 % of respondents while only 37 % advised their patients to use fluoridated toothpastes. Younger respondents (≤35 years) were more likely to identify the commonly-known causative factors for DE (P = 0.024). Twenty-seven percent of the respondents reportedly used an index to grade DE. Dental students were more likely than dentists to use such an index (P <0.001) and to more frequently advise their patients to reduce intake of acidic drinks (P = 0.02) compared to dentists. CONCLUSIONS: In-depth knowledge about causative factors, diagnosis and preventive methods of DE was apparent among only half the respondents and approaches to early diagnosis were insufficient. There would appear to be an urgent need for enhancing awareness and knowledge about DE within the Yemeni dental community.

General and orofacial symptoms associated with acute and long COVID in 80- and 90-year-old Swedish COVID-19 survivors.

OBJECTIVES: To describe acute and long COVID-19 symptoms among older elderly Swedes and to find predictive factors for the development symptoms associated with acute and long COVID. MATERIAL AND METHODS: A questionnaire about general and oral health was mailed to all 80-year-olds (born 1942, n = 6299) and 90-year-olds (born 1932, n = 1904) in two Swedish counties. Participants reporting COVID-19 were asked to complete an additional questionnaire. RESULTS: Overall response rate was 66 % (n = 5375). Affirmative responses to having been sick/tested positive for COVID-19 were reported by 577 persons. Response rate to the COVID-19 questionnaire was 49 %. The majority (88 %) reported some general symptoms during the acute stage while 44 % reported orofacial symptom/s. Reporting of any form of long-COVID general symptoms was 37 and 35 % for orofacial symptoms. Predictive factors for contracting COVID-19 (based on self-report from 2017) were living in elderly housing/senior care facility (OR 1.6, CI 1.0-2.3), large number (>10) of weekly social contacts (OR 1.5, CI 1.3-1.9), being married (OR 1.4, CI 1.1-1.7) and high school/university education (OR 1.3 CI 1.1-1-6). The highest odds ratio for general symptoms of long-COVID were a single complete denture (OR 5.0, CI 2.0-12.3), reporting bad breath (OR 3.7, CI 1.9-7.2) and daytime dry mouth (OR 2.2, CI 1.1-4.2). Regarding long-COVID orofacial symptoms, the highest risk factors were bad breath (OR 3.8, CI 1.9-7.5) and a single complete denture in one jaw (OR 3.4, CI 1.2-9.8). CONCLUSION: Long-COVID general and orofacial symptoms are common among older elderly COVID-19 survivors CLINICAL SIGNIFICANCE: Oral microorganisms may be responsible for development of long-COVID symptoms. Health personnel managing COVID-19 patients should carefully examine dental status, especially in those having acrylic-based removable dentures, for oral signs and symptoms. If found, rigorous oral hygiene procedures should be carried out including cleaning/disinfection of the denture.

Clinical outcomes of single crown and 3-unit bi-layered zirconia-based fixed dental prostheses: An upto 6- year retrospective clinical study: Clinical outcomes of zirconia FDPs.

OBJECTIVES: The aim of this retrospective clinical study was to evaluate the survival and the occurrence of technical and biological complications in bi-layered zirconia-based (Zi) single crown and 3-unit fixed dental prostheses (FDPs). Also, the study aimed to analyze the effects of tooth vitality (vital versus non-vital), abutment location (anterior versus posterior), and luting cement (self-adhesive resin versus resin-reinforced glass ionomer) on clinical outcomes. METHODS: A total of 147 prostheses (in 94 patients) placed by undergraduate dental students in a university dental center during the period 2015-2021 were examined clinically using modified United States Public Health Service (USPHS) and California Dental Association (CDA) criteria. The mean duration of follow-up was 37 months (range, 6 - 63 months) for the single crowns (n = 77) and 25 months (range, 6 - 68 months) for the 3-unit FDPs (n = 70). Data were descriptively analyzed to determine the types and rates of complications based on USPHS and CDA criteria. The Kaplan-Meier survival estimation method was used to determine the cumulative survival and success rates of the prostheses (α=0.05). Differences in clinical outcomes (survival or failure) according to tooth vitality, luting cement, and location were statistically analyzed using cross-tabulations and Ð¥2 test (α=0.05). RESULTS: The Kaplan-Meier cumulative survival rate was estimated as 96% for the Zi 3-unit FDPs after 5.5 years, and 90% for the Zi single crowns after 4.8 years. The 5-year estimated success rate was 68% for both 3-unit FDPs and single crowns. Seven (9.1%) 77Zi single crowns and 70 2 (2.9%) Zi 3-unit FDPs were recorded as failures with occlusal roughness being the most commonly-observed complication (crowns: 4 [5.6%]; 3-unit FDPs: 8 [11.4%]). In terms of clinical outcomes, statistically significant differences were found between all included vital and non-vital teeth (p = .006), and cement types (p = .028). Taking single crowns alone, significant differences in clinical outcomes according to tooth vitality were noted (p = .036), but not for PFDPs. The location of the prostheses did not produce any significant differences in the clinical outcomes, for both prostheses types independently or combined (p > .05). CONCLUSIONS: The estimated cumulative survival rates in this study for single crowns and 3-unit Zi FDPs concurred with the ranges reported in systematic reviews. Zi-based prostheses on vital teeth produced better clinical outcomes than those placed on non-vital teeth, and type of luting cement influenced the final clinical outcome. CLINICAL SIGNIFICANCE: Zi crowns and 3-unit PFDPs fabricated using the specific CAD-CAM system used in the controlled environment of this study showed good clinical performance with minimal veneer porcelain chipping. Root canal treated teeth seem to be at higher risk for failure of Zi prostheses compared with vital teeth.

Prediction of xerostomia in a 75-year-old population: A 25-year longitudinal study.

OBJECTIVES: To follow the same individuals from age 50 up to 75 years to report on prevalence, persistence, progression, remission, incidence and predictors for xerostomia. METHODS: A questionnaire was distributed to all 50-years-olds (1992) in two Swedish counties (N = 8888) and repeated at the age of 65 (2007) and 75 years (2017). 3060 individuals responded on all three occasions (response rate 42.5%). Xerostomia was assessed with two questions. Additional questions addressed inter alia general/oral health and oral function. RESULTS: Reported prevalence of daytime xerostomia were 23.3% and 14.7%, and 39.5% and 27.5% in women and men, age 50 and 75, respectively. Night-time prevalence was higher. At age 50, 27.4% women and 24.0% men reported having dry mouth, and at age 75, 61.0% and 53.8%, respectively. At all time points, women reported significantly more xerostomia than men. Progression (deterioration) was common, and persistence (continuing presence) was high, while 25-year incidence for daytime xerostomia was 16.2% and 12.8%, and 33.6% and 29.8% at night-time, for women and men, respectively. Based on reports at age 50, regression analyses showed that prediction for developing xerostomia during the observation period, and reporting xerostomia at age 75 years, were female gender, impaired general health, chewing, jaw opening and intraoral problems, dissatisfaction with dental appearance, low education and having white/plastic filling. CONCLUSIONS: Xerostomia is common in older people, especially at night and in women. It can be predicted by diverse factors reported earlier in life. CLINICAL SIGNIFICANCE: Clinicians need to be made aware of that elderly often suffers from dry mouth so that they can recommend effective measures to eliminate or ease the patients accompanying symptoms and also exclude or lessen possible negative impact on oral health related to xerostomia.

Temporal changes and gender differences related to orofacial symptoms in two cohorts of 75-year-old Swedish subjects examined in 2007 and 2017: A repeated cross-sectional study.

OBJECTIVES: To compare two cohorts of 75-year-old persons, born 10 years apart, in regard to reported symptoms related to temporomandibular disorders (TMD) and orofacial complaints with special reference to gender differences. MATERIAL AND METHODS: In 2007, a questionnaire comprising questions on social factors, general and oral health, and a series of attitude-related questions was mailed to all individuals born in 1932 living in two Swedish counties (N = 5195), and in 2017 to all born in 1942 (N = 7204). The response rate for the cohort examined in 2007 was 71.9% (n = 3735) and 70.7% (n = 5091) for the cohort examined in 2017. Bivariate statistical analyses were applied. RESULTS: Reported bruxism and pain from the temporomandibular joint were significantly higher in the 1942 cohort compared to the 1932 cohort, while reports of oral lesions and daytime dry mouth were lower. Women reported problems significantly more frequently in most of the domains investigated in both 2007 and 2017, that is, TMD, burning mouth, sensitive teeth, oral lesions, taste changes, daytime/night-time dry mouth, except bad breath. CONCLUSIONS: TMD-related symptoms increased while complaints from oral lesions and daytime mouth dryness decreased between 2007 and 2017. Temporal changes were otherwise few, but the findings underline the gender inequalities that exist, to the disadvantage of women. This must be considered when planning for clinical care/dental education to appropriately address the needs of older people.

Evaluation of the marginal fit of a CAD/CAM zirconia-based ceramic crown system.

PURPOSE: To evaluate the marginal fit of zirconia (Zi) CAD/CAM crowns in terms of gap and overhang compared to lithium disilicate (LDS) computer-aided design crowns, as well as the effect of finish line design on marginal accuracy. MATERIALS AND METHODS: Stone dies were acquired from two master metal dies (n = 20 each) with two different finish lines and were scanned to produce digital models. Ceramic crowns (ZS-Ronde Zi, KaVo and IPS e.max CAD LDS, Ivoclar Vivadent) were designed and milled on the resulting 40 dies: 10 Zi-shoulder, 10 Zi-chamfer, 10 LDSshoulder, and 10 LDS-chamfer. Marginal gap and overhang were evaluated at six designated margin locations. The data were obtained, and the influence of material and finish line on the marginal fit of crowns was assessed using two-way analysis of variance and Bonferroni multiple comparisons test (α = .05). RESULTS: Mean marginal gap and overhang on Zi crowns were 30 ± 14 µm and 79 ± 27 µm for the shoulder, respectively, and were 68 ± 34 µm and 104 ± 34 µm for the chamfer. The corresponding values for LDS crowns were 57 ± 22 µm and 74 ± 29 µm for the shoulder, and 62 ± 12 µm and 59 ± 27 µm for the chamfer. ANOVA revealed that the differences in marginal gap between the two materials were not significant (P > .05), but that the finish line effect and interaction were significant (P < .05). With regard to marginal overhang, significant differences were found between Zi and LDS crowns (P < .05), although the finish line geometries did not show any significant differences (P > .05). LDS crowns showed no differences between shoulder and chamfer margins for gap or overhang (P > .05), whereas significant differences were found in marginal gap between the Zi shoulder and chamfer margins (P lt; .005). CONCLUSION: In terms of marginal accuracy, shoulder margins produced smaller marginal gaps compared to chamfers for Zi CAD/CAM crowns.

Knowledge, beliefs, attitude, and practices of E-cigarette use among dental students: A multinational survey.

BACKGROUND: E-cigarette use is a trend worldwide nowadays with mounting evidence on associated morbidities and mortality. Dentists can modify the smoking behaviors of their patients. This study aimed to explore the knowledge, beliefs, attitude, and practice of E-cigarette use among dental students. MATERIALS AND METHODS: This multinational, cross-sectional, questionnaire-based study recruited undergraduate dental students from 20 dental schools in 11 countries. The outcome variable was current smoking status (non-smoker, E-cigarette user only, tobacco cigarette smoker only, dual user). The explanatory variables were country of residence, sex, age, marital status, and educational level. Multiple linear regression analysis was performed to explore the explanatory variables associated with E-cigarette smoking. RESULTS: Of the 5697 study participants, 5156 (90.8%) had heard about E-cigarette, and social media was the most reported source of information for 33.2% of the participants. For the 5676 current users of E-cigarette and/or tobacco smoking, 4.5% use E-cigarette, and 4.6% were dual users. There were significant associations between knowledge and country (P< 0.05), educational level (B = 0.12; 95% CI: 0.02, 0.21; P = 0.016) and smoking status (P< 0.05). The country of residence (P< 0.05) and smoking status (P< 0.05) were the only statistically significant factors associated with current smoking status. Similarly, there were statistically significant associations between attitude and country (P< 0.05 for one country only compared to the reference) and history of previous E-cigarette exposure (B = -0.52; 95% CI: -0.91, -0.13; P = 0.009). Also, the practice of E-cigarettes was significantly associated with country (P< 0.05 for two countries only compared to the reference) and gender (B = -0.33; 95% CI: -0.52, -0.13; P = 0.001). CONCLUSION: The knowledge of dental students about E-cigarette was unsatisfactory, yet their beliefs and attitudes were acceptable. Topics about E-cigarette should be implemented in the dental curriculum.

Association of fit of partial denture metal framework with various framework design features using alginate as a final impression material: A prospective clinical study.

OBJECTIVES: To assess the fit of PRDP frameworks fabricated using alginate as a final impression material in metal stock trays, in terms of number of fabricated frameworks needed until realization of clinically adequate fit. Also, any association of framework fit achieved with its design features, namely major connector design, and numbers of guide plates and occlusal/incisal rests was investigated. METHODS: 147 partially dentate patients were provided with Co-Cr PRDPs, in single or both arches, by undergraduate dental students. Final impressions were made with alginate in metal stock trays. At metal framework try-in, clinical examinations were carried out by two prosthodontists and relevant information noted with regard to proper fit. The relationship between three PRDP design features and number of frameworks that needed to be made in each case to achieve satisfactory fit was determined using factorial analysis of variance (ANOVA) (α = 0.05). RESULTS: 86% (148) of the 173 frameworks fabricated were found to be clinically satisfactory at the first try-in visit (with or without any chairside adjustment). The remaining 14% (25) required new impressions for re-fabrication and passed at the second attempt. None of the examined design features were significantly associated with the number of construction attempts needed, for all 173 arches, or when maxillary and mandibular arches were considered independently (p > 0.05). CONCLUSIONS: PRDP design features were not associated with the level of accuracy of fit achieved. CLINICAL SIGNIFICANCE: Alginate in metal stock trays seems to be acceptable for final impressions of all types of Co-Cr PRDP designs with just 1 in 7 castings not fitting after chairside adjustment.

Happiness among dentists: a multi-scale, multi-national study from 21 countries.

OBJECTIVES: The extent to which dentists are happy with their profession and their life has not been well studied. The present study aimed to explore the level of happiness, satisfaction with life and psychological well-being among a sample of dental professionals from 21 countries. MATERIALS AND METHODS: The sample comprised 2,200 dentists from 21 countries. Three scales - Subjective Happiness Scale (SHS), Satisfaction With Life Scale (SWLS), and Affect Balance Scale (ABS) - were used to measure the subjective responses. Data related to demographic and social characteristics were recorded. Mann-Whitney and Kruskal-Wallis tests were used as appropriate. Scales were correlated, and multiple linear regression analyses were employed to identify the independent determinants of SHS, SWLS and ABS. Data were analysed using the SPSS software program; a value of P <0.05 was considered significant. RESULTS: The overall mean scores of SHS, SWLS and ABS were 18.53 ± 5.06, 23.06 ± 6.25 and 1.26 ± 2.40, respectively, with significant differences found across countries: dentists working in Croatia, Peru and Serbia recorded the highest scores, unlike dentists practicing in Yemen, Syria, and Iraq, who recorded the lowest scores. There were significant, moderately positive correlations between the various scales: SHS and SWLS: r = 0.535, P < 0.001; SHS and ABS: r = 0.58, P < 0.001; and SWLS and ABS: r = 0.533, P < 0.001. Country of practice, age, qualification and monthly income were the significant independent predictors of SHS, SWLS and ABS. CONCLUSION: Country of residence and social characteristics were associated with dentists' responses regarding their feelings and subjective well-being.

Recurrent caries at crown margins: making a decision on treatment.

OBJECTIVE: To evaluate dentists' treatment choices for a crowned tooth with varying degrees of recurrent caries. MATERIALS AND METHODS: A total of 158 dentists participated in the study. A paper patient case (PPC) depicting a radiograph showing varying degrees of recurrent caries at the crown margin was used: PPC1 = small carious lesion away from crown margin; PPC2 = small carious lesion at crown margin; PPC3 = small carious lesion at crown margin extending onto the root, and PPC4 = large carious lesion at the margin; PPC5-PPC8 had the same carious conditions as PPC1-PPC4, respectively, but the teeth were non-vital. Participants were asked to indicate their choice of treatment from a list of options for each PPC. Crown removal tendency was computed after dichotomization of the responses for the different cases for each participant. Demographic information, educational background and practice characteristics were collected. Descriptive statistics, logistic regression analysis and paired-sample t test were used to analyse the data at a statistically significant level of p < 0.05. RESULTS: For PPC1 and PPC5, most of the participants recommended management without crown removal (p < 0.05). For PPC6, there was wide disagreement about management (p = 0.81). For all other PPCs, the majority of participants chose to remove the crown before making a treatment decision (p < 0.05). Logistic regression analysis showed that the size of the lesion, vitality of the tooth, participants' age as well as the undergraduate training background of dentists were factors that affected treatment decisions. CONCLUSION: The data showed a lack of agreement among dentists regarding the management of recurrent caries around crown margins. Size of the lesion, vitality of the tooth, educational training and experience appeared to be the main factors that affected their decisions.