Longevity of complete dentures: A systematic review and meta-analysis

Efficient complete denture metal base design via a dental feature-driven segmentation network

BACKGROUND AND OBJECTIVE

Complete denture is a common restorative treatment in dental patients and the design of the core components (major connector and retentive mesh) of complete denture metal base (CDMB) is the basis of successful restoration. However, the automated design process of CDMB has become a challenging task primarily due to the complexity of manual interaction, low personalization, and low design accuracy.

METHODS

To solve the existing problems, we develop a computer-aided Segmentation Network-driven CDMB design framework, called CDMB-SegNet, to automatically generate personalized digital design boundaries for complete dentures of edentulous patients. Specifically, CDMB-SegNet consists of a novel upright-orientation adjustment module (UO-AM), a dental feature-driven segmentation network, and a specific boundary-optimization design module (BO-DM). UO-AM automatically identifies key points for locating spatial attitude of the three-dimensional dental model with arbitrary posture, while BO-DM can result in smoother and more personalized designs for complete denture. In addition, to achieve efficient and accurate feature extraction and segmentation of 3D edentulous models with irregular gingival tissues, the light-weight backbone network is also incorporated into CDMB-SegNet.

RESULTS

Experimental results on a large clinical dataset showed that CDMB-SegNet can achieve superior performance over the state-of-the-art methods. Quantitative evaluation (major connector/retentive mesh) showed improved Accuracy (98.54 ± 0.58 %/97.73 ± 0.92 %) and IoU (87.42 ± 5.48 %/70.42 ± 7.95 %), and reduced Maximum Symmetric Surface Distance (4.54 ± 2.06 mm/4.62 ± 1.68 mm), Average Symmetric Surface Distance (1.45 ± 0.63mm/1.28 ± 0.54 mm), Roughness Rate (6.17 ± 1.40 %/6.80 ± 1.23 %) and Vertices Number (23.22 ± 1.85/43.15 ± 2.72). Moreover, CDMB-SegNet shortened the overall design time to around 4 min, which is one tenth of the comparison methods.

CONCLUSIONS

CDMB-SegNet is the first intelligent neural network for automatic CDMB design driven by oral big data and dental features. The designed CDMB is able to couple with patient's personalized dental anatomical morphology, providing higher clinical applicability compared with the state-of-the-art methods.

Influence of new complete dentures on the touch perception threshold and quality of life of edentulous patients

OBJECTIVE

To evaluate the touch perception threshold of the alveolar mucosa and quality of life of edentulous patients before (T0) and 30 days after (T1) the insertion of new complete dentures.

BACKGROUND

Touch perception is important so that edentulous patients can detect the position of complete dentures in their mouth.

MATERIALS AND METHODS

This study included 32 complete denture wearers with good oral and systemic health and no temporomandibular disorders for at least 5 years. At each time point (T0 and T1), two tests were performed (touch perception threshold and quality-of-life scale). The touch perception threshold (Von Frey or Semmes-Weinstein test) was assessed using nylon monofilaments on the regions of the alveolar mucosa of the maxilla and mandible. The Oral Health Impact Profile for edentulous individuals (OHIP-EDENT) was administered to evaluate oral health-related quality of life.

RESULTS

In the maxilla and mandible, the touch perception thresholds for all regions of the alveolar mucosa were significantly lower at T1 than at T0. The OHIP-EDENT mean scores showed that the overall quality of life was significantly better at T1 (3.6) than at T0 (4.7), and a significant improvement in quality of life was observed in all domains of the OHIP-EDENT at T1. For touch perception threshold, effect sizes ranged from 0.4 to 0.8; and for quality of life, effect sizes ranged from 0.4 to 1.0.

CONCLUSIONS

New complete dentures reduced the touch perception threshold of the alveolar mucosa of both edentulous arches and improved individuals' quality of life.

Expediting the Rehabilitation of Severely Resorbed Ridges Using a Combination of CAD-CAM and Analog Techniques: A Case Report

With the life expectancy increasing, there is a growing need for prosthetic dental treatments to restore the oral health, function, and quality of life of edentulous patients. Presently, only a few articles are available describing the oral rehabilitation of patients with severely resorbed ridges with milled complete dentures. This clinical case report provides a straightforward protocol consisting of a combination of analog and digital techniques for the rehabilitation of edentulous patients with severely resorbed ridges with milled fixed and removable complete dentures. This technique permits the minimization of the number of appointments, improves patient comfort, allows for the digital archiving of important clinical data, and permits the manufacture of prostheses with improved mechanical properties. These favorable outcomes were achieved by using the patient's existing PMMA complete denture as a custom tray for a final impression with light-bodied Polyvinylsiloxane. Subsequently, the resulting models were digitized, and a digital complete denture was designed and manufactured in an expedited manner using CAD-CAM techniques. Therefore, this case report highlights the potential of CAD/CAM technology to predictably restabilize oral functions and improve patients' quality of life.

Women in leadership positions in dentistry: A scoping review

BACKGROUND

The objectives of this scoping review were to calculate the prevalence of women in leadership positions in dentistry, present existing research on gender (male, female) disparities affecting dentistry globally, identify gaps in the literature that can drive future research, and provide recommendations for achieving gender parity in leadership positions.

TYPES OF STUDIES REVIEWED

A search of PubMed, Web of Science, Cumulative Index to Nursing and Allied Health Literature, Embase, Google Scholar, and Cochrane Central Register of Controlled Trials databases was performed using search terms. The search strategies were developed to cover English-language articles from January 2016 through April 2022 that examined the prevalence of women in leadership positions in dentistry. Abstracts, newsletters, qualitative reports, and letters to the editors were excluded.

RESULTS

Eighteen studies met all inclusion criteria and were included in the final analysis. Low prevalence was noted of women in leadership positions in dentistry globally. Multiple reasons that have led to gender disparities were identified and recommendations for decreasing gender disparities and achieving gender equity in dentistry were provided.

PRACTICAL IMPLICATIONS

Over the years, several factors have contributed to gender inequalities in dentistry. However, during the past decade, gender equity, inclusion, and diversity have been recognized increasingly as core values of the dental profession. Presenting and analyzing all available data surrounding this topic are of paramount importance to start formulating appropriate strategies to achieve gender parity in all areas of dental leadership.

Attitudes regarding a warranty and the expected longevity of dental treatment amongst New Zealand dentists, dental students, and patients: a mixed methods survey

OBJECTIVES

To investigate and compare estimates of the longevity of dental treatment, expectations for free remedial treatment, and attitudes about formal dental warranties among dentists, students, and patients.

MATERIALS AND METHODS

This is a mixed-method cross-sectional questionnaire survey with convenience sampling from dentists, dental students, and patients in New Zealand. A questionnaire was distributed to New Zealand dentists (n = 28) and final-year dental students (n = 27). A separate questionnaire was provided to patients in a university dental clinic (n = 43). Mann-Whitney U, Chi-square and Pearson Correlation, and Binary logistic regression tests were used to test for differences between groups and correlations amongst variables. Qualitative data were analysed thematically.

RESULTS

Dentists believed that their posterior composite resin restorations would last longer (p = 0.014), would remediate failed crowns for longer (p = 0.002) and would provide longer crown warranties (p = 0.003) compared to students. Patients had higher expectations for restoration longevity and free remediation for failed treatment. Students were generally more willing to provide warranties. Crowns were perceived to be the most warrantable, while endodontic treatment was the least warrantable. Recall attendance, mechanical failure, and adequate oral hygiene were commonly proposed as warranty conditions for restorations and crowns. There was little consensus about complete dentures and endodontic treatment.

CONCLUSIONS

There are significant disparities between the expectations of patients and clinicians regarding treatment longevity and free remediation times. Clinicians, in general, are willing to provide free remediation within a specified time frame, except for endodontic treatment, but are hesitant to provide formal dental warranties.

Post-cure Heat Treatments Influence the Mechanical and Optical Properties of Acrylic and Bis-acryl Composite Resins

OBJECTIVE

To evaluate the influence of post-cure heat treatments (PCHT) on Knoop microhardness (KHN) and color change of bis-acryl composite resin (Protemp 4 - 3M ESPE, USA and PrimmaArt - FGM, Brazil) and chemically activated acrylic resins (Dencôr - Clássico, Brazil, and Duralay - Cotia, Brazil).

METHODS AND MATERIALS

Specimens (12×1 mm) were prepared for each material (n=10/group). Thirty minutes after curing, the specimens were subjected to PCHT for 10 minutes at 70°, 100°, or 130°C. The control group was kept at room temperature (24°C) for the same amount of time. KHN was analyzed 24 hours after PCHT (n=10). Following Commission Internationale de l'Éclairage (CIE) Delta E 2000 (CIEDE2000 [ΔE00]), color measurements were obtained at three time points: 1. after polymerization; 2. after PCHT; and 3. after 30 days of storage in water, coffee, or red wine. Data for each material were analyzed by one-way analysis of variance (ANOVA) (p<0.05).

RESULTS

The PCHT at 130°C produced the highest KHN values. Except for the 70°C groups from Dencôr and Protemp, all PCHTs increased the initial color values (p>0.05). In general, chemically activated acrylic resins showed an increase in color stability when subjected to PCHT (p>0.05). For bis-acryl composite resin, PCHT did not influence color stability (p<0.05).

CONCLUSION

Overall, the results showed that PCHT increased the tested materials' color changes and Knoop microhardness. However, except for PCHT at 130°C in Duralay, the color changes remained within acceptable values. The PCHT treatment resulted in better color stability for most of the composite resins studied.

Modeled health economic and equity impact on dental caries and health outcomes from a 20% sugar sweetened beverages tax in Australia

Dental caries is the most prevalent oral disease across the life course. This study modeled the population health and economic impact of a 20% sugar sweetened beverages tax (SSB) for preventing dental caries compared to no intervention (societal and healthcare perspective). A cost-effectiveness analysis according to quintiles of area-level socioeconomic disadvantage was performed for the 2020 Australian population (0-100 years old) using a closed cohort Markov model. A qualitative assessment of implementation considerations (e.g., acceptability, equity, sustainability) was undertaken. Health outcomes were modeled as decayed teeth prevented and disability-adjusted life years (DALYs) averted. The 10-year and lifetime scenarios were modeled with probabilistic sensitivity analysis (Monte Carlo simulation, 2000 cycles). The 10-year scenario from a societal perspective yielded cost-savings of AUD$63.5M, healthcare cost-savings of AUD$42.2M, 510,977 decayed teeth averted and 98.1 DALYs averted. The lifetime scenario resulted in societal cost savings of AUD$176.6M, healthcare cost-savings of AUD$122.5M, 1,309,211 decayed teeth averted and 254.9 DALYs averted. Modeling indicated 71.5% and 74.5% cost-effectiveness for the 10-year and lifetime scenarios, respectively. A three-fold health benefit for the least advantaged was found compared to the most advantaged. A 20% SSB tax in Australia is cost-effective and promotes health equity.

Differences in complete denture longevity and replacement in public and private dental services: A propensity score-matched analysis of subsidised dentures in adult Australians across 20 years

OBJECTIVES

To examine the differences in treatment outcomes for patients who received subsidized complete dentures in private dental clinics and in public dental clinics over 20 years in Victoria, Australia.

METHODS

Between 2000 and 2019, 187 227 complete dentures were provided to eligible public patients by the Victorian public dental system. Of these, approximately 52% were provided to public patients in private clinics through the voucher system. Of the 97 107 participants who received denture care in private clinics, 70 818 were matched 1:1 by propensity score (PS) quantiles with participants who received denture care in public clinics. The PS matching balanced the characteristics between these two groups. Subsequently, a conditional logistic regression model investigated the binary outcome of denture replacement whilst a conditional Poisson regression modelled the number of years to denture replacement. A frailty Cox regression after PS matching investigated denture survival over time.

RESULTS

Dentures provided in public clinics had a mean time to replacement of 5.5 years (SD: 34.0) and 25.9% were replaced during the observation period. In the first year of denture service, incidence rate per person year (IR) for complete denture replacement in public clinics was 0.04 (95% CI: 0.04-0.04). Dentures provided in private clinics had a mean time to replacement of 6.5 years (SD: 3.8) with 29.4% replaced during the observation period. In the first year of denture service, the IR for complete denture replacement in private clinics was 0.02 (95% CI: 0.02-0.02), which was less than half that of the public IR. Multivariate analyses found that although private dentures were more likely to be replaced during the observation period than those provided in the public sector (odds ratio [OR]: 1.31, 95% CI: 1.28-1.35, p < .001), they had greater longevity (incidence rate ratio [IRR]: 1.23, 95% CI: 1.23-1.24, p < .001). Longer longevity of private dentures was also supported by the frailty Cox regression showing that private dentures had a reduced hazard of denture replacement over time (better survival) in comparison to public dentures (hazard ratio [HR]: 0.94, 95% CI: 0.92-0.97, p < .001). Probabilistic sensitivity analysis supported the study findings.

CONCLUSIONS

Increased denture longevity, higher rates of denture replacement and lower rates of early denture replacement were associated with receiving denture care in private clinics as compared with dentures provided in the public sector.

Treatment of an edentulous patient over 23 years showing the influence of systemic health on oral health and quality of life

This case history follows the treatment of a 61-year-old edentulous woman over a period of 23 years. The patient was wearing complete dentures for 25 years prior to treatment, was in pain, and having difficulty eating. Many treatments were tried, including multiple soft liners, hydroxyapatite to improve her mandibular ridge, and finally an implant-supported-overdenture. However, in spite of using all the technical procedures and materials available to us at the time of treating the patient, we were unable to sustain the comfort and quality of life for this patient. This happened because of the severe resorption of her mandible, with an intolerance to occlusal loading, and the continuous deterioration of her systemic health.

2D and 3D Wear Analysis of 3D Printed and Prefabricated Artificial Teeth

PURPOSE

This study aimed to assess the 3-body wear of prefabricated and 3D-printed artificial denture teeth.

MATERIALS AND METHODS

Four groups of artificial teeth were used; 3D-printed polymethylmethacrylate (PMMA) teeth (PR) and 3 prefabricated commercially available denture teeth: PMMA (Gnathostar, GN), PMMA (SR Orthotyp PE, SR), and Nanohybrid composite (SR Phonares NHC, PH). The 3-body wear test was performed using a steatite ceramic antagonist in a chewing simulator with 750,000 cycles, temperature 23 ± 2 ˚C, and force of 50 N. The abrasive medium was composed of ground millet seeds and white rice mixed with distilled water. The teeth were 3D-scanned before and after the wear test. The 3D images were assessed for teeth wear by measuring the volumetric (3D wear) and the vertical (2D wear) substance loss. The one-way analysis of variance followed by Tukey post hoc test was used to statistically obtain the data analysis.

RESULTS

Maximum 3D wear was observed in the PR (51.05 ± 4.53 mm³), followed by GN (20.22 ± 6.29 mm³) and SR (12.12 ± 6.29 mm³) artificial teeth. Minimum wear occurred in the PH teeth (6.24 ± 0.87 mm³). The analytical differences amongst the groups were statistically significant (P < .05) except between PH and SR teeth. For 2D wear measurement, the maximum was seen in the GN teeth (6.29 ± 1.64 mm), followed by PR (5.04 ± 0.83 mm) and then SR (4.53 ± 0.87 mm). The PH teeth (3.09 ± 0.68 mm) again showed minimum wear. Statistically, amongst the groups, the major observable differences (P < .05) were between PH and GN, PH and PR, and SR and GN.

CONCLUSIONS

Composite resin teeth had a greater wear resistance than acrylic resin teeth and 3D-printed resin teeth, both of which were comparable. Due to the advancement of digital workflows, manufacturers should devote effort to enhancing 3D-printed teeth.

Annual review of selected scientific literature: A report of the Committee on Scientific Investigation of the American Academy of Restorative Dentistry

The Scientific Investigation Committee of the American Academy of Restorative Dentistry offers this review of the 2021 dental literature in restorative dentistry to inform busy dentists regarding noteworthy scientific and clinical progress over the past year. Each member of the committee brings discipline-specific expertise to coverage of this broad topical area. Specific subject areas addressed, in order of the appearance in this report, include COVID-19 and the dental profession (new); prosthodontics; periodontics, alveolar bone, and peri-implant tissues; implant dentistry; dental materials and therapeutics; occlusion and temporomandibular disorders; sleep-related breathing disorders; oral medicine and oral and maxillofacial surgery; and dental caries and cariology. The authors focused their efforts on reporting information likely to influence daily dental treatment decisions with an emphasis on future trends in dentistry. With the tremendous volume of dentistry and related literature being published daily, this review cannot possibly be comprehensive. Rather, its purpose is to update interested readers and provide important resource material for those interested in pursuing greater details on their own. It remains our intent to assist colleagues in negotiating the extensive volume of important information being published annually. It is our hope that readers find this work useful in successfully managing the patients and dental problems they encounter.

The effect of clinical interventions on the oral health-related quality of life in older adults

This paper reviews the literature to assess the effectiveness of oral health interventions in influencing oral health-related quality of life (OHRQoL) in older adults. Clinical studies published in 2010 onwards reporting oral health interventions in older adults and subsequent changes in OHRQoL were systematically searched in Medline, Web of Science and EMBASE databases. Reporting followed Preferred Reporting Items for Systematic Review and Meta-Analysis criteria. Eligibility evaluation and data abstraction from eligible studies were guided by predefined PICO questions and bias assessment by the Quality in Prognosis Studies tool. The search retrieved 144 articles. Of the 20 articles that met the eligibility criteria, 45% (9) reported a statistically significant improvement in OHRQoL. The majority of studies were conducted in adults with complete edentulism (70%) and mainly focused on implant provision to support a removable prosthesis (30%). The search indicates the limited scope of current literature on geriatric dental interventions, focusing mainly on denture realignments, denture fabrication and implant placement. Although the majority of the oral health interventions focused on edentulism and removable prostheses, there are many areas of oral health interventions and their potential impact on OHRQoL in this demographic group that have yet to be explored.

Health Literacy Among University Students: A Systematic Review of Cross-Sectional Studies

OBJECTIVE

The aim of this systematic review was to provide an overview of cross-sectional studies that examined health literacy among university students and to identify possible determinants related to health literacy.

METHOD

The current review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Three databases (PubMed, Scopus, and Web of Science) were systematically searched for cross-sectional studies that examined health literacy among university students. Results of included studies were narratively summarized.

RESULTS

The systematic review includes twenty-one research studies. The majority of studies report health literacy scores among university students that are lower compared to reference samples. The health literacy of students is influenced by different variables (age, gender, number of semesters, course of studies/curriculum, parental education, and socioeconomic background).

DISCUSSION

Health literacy activities should target all students. Universities should make use of their resources and offer health literacy courses for students in which content is used from disciplines available at the university (e.g., medicine, health, or psychology). To increase effectiveness, health literacy courses should be adapted according to the different needs and characteristics of the student subgroups.

Complete denture replacement: a 20-year retrospective study of adults receiving publicly funded dental care

PURPOSE

There is little evidence as to what is the appropriate replacement interval for complete dentures. The aim of this study was to determine the longevity of complete dentures in a population of publicly insured adults across a 20 year observation period.

METHODS

The records of 187,227 Australian adults who accessed complete denture treatment through public clinics between 2000-2019 were assessed. Time to denture replacement was modelled using a Weibull regression and a competing risk regression to adjust for the competing risk of mortality.

RESULTS

Over a 20-year period, 27.7% of dentures were replaced, with a mean longevity of 6.06 (SD: 3.93) years. Pairs of complete dentures had greater mean longevity than single dentures (p<0.001). Approximately 4.6% of dentures provided were replaced within 2 years; 18.4% were replaced between 2 and 10 years and 4.6% of replacements occurred after 10 years.Over 70% of adults who received a complete denture did not replace it during the observation period. Dentures provided by denturists had higher levels of replacement than those made by dentists. Participants over 80 years of age had lower rates of denture replacement. Low socio-economic status and living outside a major city were associated with reduced rates of replacement for dentures under 10 years of age.

CONCLUSION

Complete dentures were commonly replaced after 6 years of service. Pairs of dentures lasted longer than single dentures.

The Tridirectional Relationship among Physical Activity, Stress, and Academic Performance in University Students: A Systematic Review and Meta-Analysis

Higher education students often suffer from physiological and psychological health problems caused by stress, which may negatively impact their academic performance (AP). Physical activity (PA) can be a promising strategy to buffer these stress-induced complaints. Therefore, the aim of this investigation was to summarize evidence for the tridimensional construct of PA, stress, and AP, as well as to quantify the relationships among these variables. Five databases (PubMed, Scopus, SMEI, ERIC, and Web of Science) were systematically searched in November 2019 for publications that examined PA, stress, and AP of university students, without any restrictions regarding the publication period. The systematic review includes four original research studies with a moderate-to-high risk of bias. Results of included studies were narratively summarized and quantified in a meta-analysis using random effect models. Whereas study results point to a positive relation between PA and AP, relationships between PA and stress seem to be negative, while the relation between stress and AP is undecided. The meta-analysis found no significant associations and considerable heterogeneity of the results. Findings indicate a research gap concerning the connection of PA, stress, and AP in university students. Future studies should use validated measuring tools and consider the timepoint of data collection in order to extract truly stressful periods.