Evidence-based guidelines for the care and maintenance of complete dentures: a publication of the American College of Prosthodontists

Highly Adaptive Kirigami-Metastructure Adhesive with Vertically Self-Aligning Octopus-like 3D Suction Cups for Efficient Wet Adhesion to Complexly Curved Surfaces

An essential requirement for biomedical devices is the capability of conformal adaptability on diverse irregular 3D (three-dimensional) nonflat surfaces in the human body that may be covered with liquids such as mucus or sweat. However, the development of reversible adhesive interface materials for biodevices that function on complex biological surfaces is challenging due to the wet, slippery, smooth, and curved surface properties. Herein, we present an ultra-adaptive bioadhesive for irregular 3D oral cavities covered with saliva by integrating a kirigami-metastructure and vertically self-aligning suction cups. The flared suction cup, inspired by octopus tentacles, allows adhesion to moist surfaces. Additionally, the kirigami-based auxetic metastructure with a negative Poisson's ratio relieves the stress caused by tensile strain, thereby mitigating the stress caused by curved surfaces and enabling conformal contact with the surface. As a result, the adhesive strength of the proposed auxetic adhesive is twice that of adhesives with a flat backbone on highly curved porcine palates. For potential application, the proposed auxetic adhesive is mounted on a denture and performs successfully in human subject feasibility evaluations. An integrated design of these two structures may provide functionality and potential for biomedical applications.

Dry Mouth Dilemma: A Comprehensive Review of Xerostomia in Complete Denture Wearers

Xerostomia, commonly known as dry mouth, presents a significant challenge for individuals wearing complete dentures, affecting their oral health and quality of life. This review explores the relationship between saliva and complete dentures, highlighting the varied management strategies for xerostomia. Saliva plays a critical role in denture retention, lubrication, and oral environment buffering. Complete denture wearers often experience reduced salivary flow, aggravating symptoms of xerostomia. Various management approaches are discussed, including general measures such as hydration and salivary stimulation techniques which aim to boost saliva production naturally. The use of salivary substitutes provides artificial lubrication and moisture to alleviate dry mouth discomfort. Oral lubricating devices, such as sprays, gels, and lozenges, offer relief by mimicking saliva's lubricating properties, thereby improving denture stability and comfort. This review addresses the etiology of xerostomia in complete denture wearers and explores preventive measures to reduce its impact. A comprehensive approach has been discussed for the management of xerostomia which will help to improve the oral health and well-being of complete denture wearers experiencing dry mouth.

Behaviors, hygiene habits, and sources of care among removable complete and partial dentures wearers: A multicenter cross-sectional study

OBJECTIVES

There is a lack of data regarding the hygiene practices and sources of care among individuals in Yemen who wear removable complete and partial dentures. The purpose of this study was to explore the behaviors, hygiene habits, and sources of care information among patients who utilize complete and partial dentures in Yemen.

MATERIALS AND METHODS

A descriptive cross-sectional research design was utilized, and a sample of 217 consecutive participants who wore removable complete and/or partial dentures were enlisted. A questionnaire was employed to collect data on demographic information, educational attainment, denture habits, denture cleaning practices, and encountered difficulties. Statistical analysis was conducted using SPSS software, and significance was determined using chi-square tests, with a significance level of .05.

RESULTS

The data analysis revealed that a majority of the participants were male (72.4%) and had an average age of 65.14 years. Fifty-three percent of the participants wore partial dentures, while 34.6% wore complete dentures. Only 6.5% of the participants wore both complete and partial dentures, and 6% wore overdentures. The majority of participants (88.47%) had dentures made of acrylic material. Additionally, 43% of participants wore dentures while sleeping, and 61.3% stored their dentures in dry places without a water-filled container when not in use. The most commonly reported cleaning methods were water only (24.4%), followed by water and soap (19.4%). Furthermore, a large portion of the participants (59.4%) received denture care information from dentists. However, the majority (59%) did not visit a dentist for regular denture maintenance or any denture-related issues. The data analysis did not reveal any significant association between age or education level and denture cleaning methods.

CONCLUSION

This cross-sectional survey provides insight into the hygiene knowledge and practices of removable denture wearers in Yemen. The findings underscore the necessity for enhanced oral hygiene education and awareness within this population. The study offers valuable insights for oral health professionals to design targeted interventions and educational initiatives aimed at promoting proper denture care and maintenance. These efforts have the potential to enhance the oral health and overall well-being of removable denture wearers.

Denture care and oral health-related quality of life among complete denture wearers in Eastern Province of Saudi Arabia

INTRODUCTION

This study aimed to evaluate denture care and hygiene and oral health-related quality of life (OHRQoL) among complete denture (CD) wearers in the Eastern Province of Saudi Arabia.

METHODOLOGY

This cross-sectional study was conducted on CD wearers in the Eastern Province of Saudi Arabia. A pre-tested questionnaire was administered among study participants. Questionnaire was divided in three sections: (1) patients' demographic data, (2) awareness and maintenance of CD and (3) OHRQoL. Independent sample t-test and one-way ANOVA test were performed.

RESULTS

The study included data of 300 participants with 71% of males and 28% of females. Majority of participants (82.7%) cleaned CD daily, removed CD while sleeping (88.0%) and knew that unhygienic dentures can cause oral infection (92.7%). Only 19.3% used denture cleansing tables, 41% used toothpaste, and 60.7% rinsed CD with water. Regarding OHIP-DENT domains, highest score was for functional limitation domain (2.20 ± 1.67) and the lowest for handicap domain (0.94 ± 1.09). The mean OHIP-DENT score of the sample was 12.02 ± 8.52. Females (p = 0.006), participants below 65 years of age (p = 0.029), non-Saudis (p = 0.042), those with university education (p = 0.030) and low monthly income (p = 0.045) and participants who visited dentist due to problem with CD (p = 0.041) demonstrated significantly higher mean OHIP-DENT score.

CONCLUSION

Majority of participants demonstrated appropriate denture care behaviours because they were aware of the importance of denture care and hygiene. Female gender, age below 65 years, non-Saudi nationality, university education, low monthly income and visiting dentist due to problem were related to poor OHRQoL.

Assessment of usefulness and reliability of YouTube™ videos on denture care

INTRODUCTION

The world's population is in a demographic transition with a rising ageing population. Tooth loss is frequent among older people resulting in the replacement of natural teeth using complete or partial dentures. YouTube™ is the second most popular website in the world and is being increasingly used to access health care information. The aim of this study is to evaluate the usefulness and reliability of the information in YouTube™ videos regarding denture care.

METHODS

The YouTube™ website was used to systematically search for videos using the keyword 'denture care'. Videos meeting the eligibility criteria were assessed separately by two independent researchers. The usefulness of the videos was assessed using the Global Quality Assessment Scale and a customized usefulness scoring scheme. Based on these scores, the usefulness of the videos was categorized as low, medium and high. A modified DISCERN tool (mDISCERN) was used for assessing reliability with scores ranging from 0 to 5. Other video characteristics like source/ownership of the videos, duration, views, likes, dislikes, number of days posted, like ratio, view ratio, interaction index and Video Power Index were also obtained. Statistical analysis was carried out using the Kruskal-Wallis test, Spearman correlation test and multiple linear regression analysis.

RESULTS

A total of 120 videos were included. Based on the usefulness score, the usefulness of 65.8% of videos were classified as low, 32.5% were medium and 1.6% had high usefulness. The mDISCERN score for 74.2% of videos was 2 or below 2 indicating that the majority of videos had low reliability. Video characteristics did not differ significantly according to the usefulness of videos. Videos uploaded by dentists or dental hygienists had significantly higher usefulness scores (p < 0.001) in comparison to videos uploaded by other sources. However, reliability scores did not differ based on the sources of the videos. Video reliability was found to have a significant (B = 2.08, p < 0.001) positive association with video usefulness.

CONCLUSION

YouTube™ cannot be recommended as the only source of information for denture care as most videos received low usefulness and reliability ratings in our study. Dentists and dental health professionals could take an active part in enhancing denture care-related content on YouTube™ and enable patients to have adequate and reliable knowledge of denture hygiene practices.

The Assessment of Awareness and Attitudes About the Use of Denture Adhesives Amongst Dental Practitioners in Northern Maharashtra: A Delphi Technique

AIM

The goal of this research was to facilitate dialogue and interaction among a group of dental practitioners about their views on denture adhesives, with the objective of reaching a collective consensus through the application of the Delphi Method.

METHODS

This investigation employed the Delphi Technique, involving multiple rounds of questionnaires sent to a panel of experts. The objective was to establish a consensus (defined as over 70% agreement) or to explore the different viewpoints on the subject. A comprehensive Delphi questionnaire comprising 22 items was distributed to the Dental Practitioners. The questionnaire covered five key areas concerning denture adhesives: (1) overall perceptions; (2) the role in the development of clinical conditions; (3) specific applications and potential misuses; (4) their importance in denture services, including educating patients about denture adhesives; and (5) a general assessment of their clinical applications.

RESULTS

All 31 panellists, chosen randomly, unanimously agreed to participate, with each of them actively involved in all three rounds of the survey. The panellists reached a consensus and definitively concluded that denture adhesives (1) are beneficial for enhancing the fit and comfort of the prosthesis and are not used to mask the underlying denture problems; (2) cause diseases such as denture stomatitis, candidiasis, and resorption of alveolar bone; (3) have the potential for increasing retention, function, and reducing patient anxiety. However, the panellists did not achieve a consensus on whether denture adhesives cause nausea and gagging in the patients; (4) education is very important for patients with both ill-fitting and well-fitting dentures; (5) are a beneficial adjunct to dentists when fabricating dentures.

CONCLUSION

The expert panel of distinguished dental practitioners determined that denture adhesives play a valuable supportive role in the field of denture prosthetics, serving important functions during both the creation and post-insertion stages of dentures.

Influence of denture brushing on the surface properties and color stability of CAD-CAM, thermoformed, and conventionally fabricated denture base resins

PURPOSE

To assess the influence of denture brushing on the surface roughness, hardness, and color stability of conventional, thermoformed, and CAD-CAM denture base materials.

MATERIALS AND METHODS

Seven different denture base materials were included in this study; conventional heat-polymerized acrylic resin (PMMA) served as control, polyamide, acetal, two categories of milled acrylic discs (AvaDent and IvoCad), and two categories of 3D-printed resins (NextDent and FormLabs). The specimens were constructed according to manufacturers' instructions and then subjected to simulated brushing (20,000 cycles). According to the brushing method, the specimens were split into three groups, no brushing, brushing with water, and brushing with toothpaste. Surface roughness, hardness, and color change were evaluated before and after brushing. Collected data were analyzed using ANOVA, and post-hoc Tukey's tests (α = 0.05).

RESULTS

A significant difference was noted between the surface roughness of the tested materials before and after denture brushing (p < 0.05), and milled resin showed the least Ra values. Denture brushing with water significantly increased the Ra of PMMA (p = 0.004) and IvoCad (p = 0.032), while brushing using toothpaste did not show a significant increase. The brushing protocols did not alter the hardness of tested materials except that of PMMA (p = 0.001). The color stability of the tested materials showed comparable results with both brushing protocols.

CONCLUSION

The tested properties showed variations between the types of denture base resins. Hardness and color stability of CAD-CAM and thermoformed denture base resins were not altered by denture brushing and showed comparable results with both brushing methods. Surface roughness was the only property that showed alteration after denture brushing.

Feasibility of microencapsulated phytochemical as disinfectant for inhibition of Candida albicans proliferation on denture base produced by digital light processing

BACKGROUNDS

A proper disinfection of denture is vital to prevent a fungal infection. A study on the feasibility of microencapsulated phytochemical as complementary disinfectant and its interaction with effervescent tablet immersion on denture base resin is lacking.

OBJECTIVES

The aim of this study was to examine the feasibility of phytochemical-filled microcapsules as disinfectant for the inhibition of Candida albicans (C. albicans) attachment on the denture base produced by digital light processing (DLP).

METHODS

54 denture base specimens uniformly mixed with or without 5wt% phytochemical-filled microcapsules were prepared using DLP. Fungal cells were inoculated onto the surfaces of the specimens, which were divided into three different disinfection treatment groups (n = 9): 1) none, 2) sterile tap water immersion for 15 min, and 3) effervescent tablet immersion for 15 min. After each treatment, the biofilm on denture surface was stained with a crystal violet solution to measure the absorbance. The number of fungal colonies was counted as colony-forming units (CFU) per mL. Morphological changes were examined by microscopy. An aligned rank transform analysis of variance was performed to analyze the interaction of presence of microcapsule and disinfection condition, with statistical significance set at P < 0.05.

RESULTS

Both for the absorbance and CFU, there was no significant interaction between the presence of microcapsules and disinfection conditions (P = 0.543 and P = 0.077, respectively). The presence of microcapsules was statistically significant (both P < 0.001), while the effect of disinfection condition was not significant (P = 0.165 and P = 0.189, respectively). Morphological changes in fungi were detected in the groups containing microcapsules, whereas undamaged hyphal structures were found in those without microcapsules, irrespective of disinfection treatments.

CONCLUSIONS

The presence of phytochemical-filled microcapsules significantly reduced the adhesion of C. albicans and inhibited its proliferation on denture surfaces, regardless of disinfection conditions.

The stain resistant effect of an ultraviolet curable coating material on denture base resin

This study aimed to evaluate the effects of an ultraviolet (UV) curable coating material on denture base resin. The results of the three-point bending test showed no significant difference between treated and untreated specimens, suggesting that the UV curable coating material did not compromise the physical strength of denture base resin. The surface free energy measurement and the surface analysis with atomic force microscopy revealed superhydrophilicity and a regularly arranged structure on the coating surface, improving wettability. Moreover, untreated specimens were significantly discolored in the staining test. However, specimens treated with the UV curable coating material showed no significant difference in color with slight staining, suggesting excellent antifouling ability. Therefore, the UV curable coating material used in this study could contribute to simplifying hygiene without altering the physical properties of denture base resins.

Effect of cigarette smoke and denture cleansers on the surface properties and color stability of CAD-CAM and conventional denture base resins

This study aimed to evaluate the hardness, roughness, and color stability of heat- and microwave-polymerized polymethyl methacrylate (PMMA), polyamide, and CAD-CAM PMMA resins when exposed to cigarette smoke (CS) and immersed in a denture cleanser (DC). Specimens of each resins were divided into four subgroups (n=10). The DC and CS+DC specimens were immersed in a DC; the CS and CS+DC specimens were exposed to CS; and the control (C) specimens were kept in distilled water. Hardness, roughness, and color measurements were performed. DC and CS significantly affected the roughness and color of all resins (p<0.05). However, these did not affect the hardness of the CAD-CAM PMMA resin (p>0.05). The CAD-CAM PMMA resin presented the lowest roughness, highest hardness, and lowest ΔE₀₀ values. While the roughness of all resins exposed to CS when immersed in DC decreased, the ΔE₀₀ values of the conventional PMMAs also decreased. Although this decreases were not significant, it may be advisable to use DC for smokers to decrease discoloration and roughness especially for conventional PMMAs resins.

Decision to use denture adhesive in complete denture wearers after one-month run-in period: A quasi-experimental study

OBJECTIVES

The aim of this study was to assess two patient-based outcomes of complete denture (CD) wearers who continued or discontinued using denture adhesive (DA) after one-month run-in period of DA use.

METHODS

This quasi-experimental study comprised 76 CD wearers. The two patient-based outcomes were oral health-related quality of life and masticatory performance, determined by the Thai-version of oral impacts on daily performances index and multiple sieve method of 20-stroke peanut mastication. Denture retention and stability were evaluated using the CU-modified Kapur criteria to classify the CD into acceptable or unacceptable quality. The outcomes were collected at 3 time points: 1) at baseline (T0), 2) after a 1-month run-in period of DA use (T1), at which time the participants decided whether to continue using DA, and 3) 1-month after continuing or discontinuing using DA (T2). Changes in the percentages of having an oral impact from T0 to T2 were evaluated using the McNemar's test. The effect of denture quality and the decision to use DA on peanut particle size across time points were assessed using repeated measures ANOVA. The peanut particle size changes in each group between time points were evaluated using the one-way repeated measures ANOVA and Tukey post-hoc comparison test.

RESULTS

The participants who continued using DA at T2 had greater oral impact reduction after the 1-month run-in period of DA use, whereas cleaning and emotional impacts emerged in those who discontinued using DA. At T1 and T2, the peanut particle size of the participants who continued and discontinued using DA was not significantly changed from T0, except for the acceptable CD wearers who discontinued using DA at T2, whose peanut particle size decreased from T0 to T2.

CONCLUSIONS

Baseline oral impacts and their change influenced CD wearers' decision whether to continue using DA. However, masticatory performance did not affect the patients' decision.

An in vitro study on the selection of surfactants for removal of cream denture adhesives from dentures and their application to denture cleaners

PURPOSE

Denture adhesives improve the stability of incompatible dentures; however, complete removal of adhesives after use is difficult. Only a few studies have focused on the removal of denture adhesives. Hence, this study aimed to assess the efficacy of surfactants in removing cream denture adhesives from acrylic resin materials.

METHODS

Solutions of twelve surfactants with various hydrophilic-lipophilic balance (HLB) values were prepared. Two cream denture adhesives, colored for visualization, were spread onto transparent acrylic resin plates. After immersion into surfactant solutions, the effects of the surfactants on residual adhesives were evaluated. We also investigated the effect of denture cleaners (with or without the surfactants) on the removability of adhesives and artificial oily dirt, and their effects on the surface properties of denture materials. The obtained data were analyzed using appropriate statistical methods.

RESULTS

Five surfactants [BT-5, BL-4.2, BT-7, BT-9, and Triton X-100 (TX)] with HLB values in the 10.5-13.5 range effectively removed adhesives. Addition of BT-9 and TX (HLB=13.5) to denture cleaners improved the adhesives' removal. Furthermore, the addition of TX to the cleaners did not interfere with the removal of artificial oily dirt and did not damage the denture materials' surface.

CONCLUSION

Surfactants with HLB values in the 10.5-13.5 range are suitable for removal of cream denture adhesives from acrylic resin materials. In particular, TX (HLB=13.5) efficiently removes adhesives without damaging denture materials or impairing original detergency.

Evaluation of dynamic impression lining material effects on masticatory function and the oral health-related quality of life of complete denture wearers: A six-month randomized controlled trial

PURPOSE

To determine the effect of a dynamic impression lining material (DIL) on the retention and stability of mandibular complete dentures (LCD), masticatory performance, and the oral health-related quality of life (OHRQoL) of the patients wearing complete denture (CD) compared with those wearing a denture with conventional hard denture liner (HL).

METHODS

Twenty-five patients who wore CD with an ill-fitting LCD were randomly assigned to two groups: LCD relined with DIL (Dynamic impression lining material) or HL (Tokuyama^® Rebase II (fast)). Three objective measures (denture retention, stability, and masticatory performance) were measured. The OHRQoL was also measured using the Thai version of oral impacts on daily performance. Outcomes were measured at six time points: baseline, 3 days, 1 week, 1 month, 3 months, and 6 months after relining. Outcome changes were analyzed using a generalized estimating equation, and all models were adjusted for age, mandibular ridge form, and CD age at a 5% significance level.

RESULTS

After LCD relining, the frequency and severity of adverse oral impacts significantly decreased. In the DIL group, denture pain occurred on and off over six months, and an ill-fitting denture impacted at one month. In the HL group, denture pain continuously decreased over time. At 3 months, changes in the clinical properties of DIL were observed, including perceived odor. The material also peel-off from the denture base, and plaque accumulation was observed. In contrast, the HL properties remained stable for over 6 months.

CONCLUSION

Although DIL improves denture retention and stability, masticatory performance, and the OHRQoL of the patients who wear CD, oral adverse effects were not eliminated. The clinical properties of DILs changed at 3 months, while the HL remained relatively stable for up to 6 months.(The clinical trial registration number: Thai Clinical Trials Registry (TCTR) number TCTR20210625005.).

Properties and characteristics of foam denture cleaners as denture adhesive removers

The need for denture adhesives is increasing worldwide, but few denture-care products target denture adhesive users. Foam denture cleaners have been recently marketed to assist brush denture cleaning, but there is a lack of objective evaluation. In this study, we compared the detergency of denture adhesives using six commercial foam-denture cleaners. For removing the adhesives, most of the tested cleaners were effective in immersion experiments, and three cleaners were more effective in the denture cleaning experiment compared to control water. However, only one could effectively remove the slime that is derived from the adhesive and detergency of artificial dirt. The surface roughnesses of the denture base and the relining material revealed that prolonged immersion in some cleaners could be affected. The results suggest that different commercial foam denture cleaners have different detergency levels, and that some cleaners may affect the properties of denture materials upon long-term use.

Hypothetical Model of How a Clinical Remount Procedure Benefits Patients with Existing Dentures: A Narrative Literature Review

The clinical remount procedure, which involves remounting the dentures on an articulator with interocclusal records, can effectively reduce occlusal discrepancies. This procedure can be applied not only to new dentures but also to those already in service; however, research in this field is still scarce. This narrative review aims to establish a hypothetical mechanism and possible indications and contraindications for this technique as a basis for further research. Current studies have revealed a high prevalence of malocclusion in delivered dentures. Performing a clinical remount on these existing dentures would enhance the oral function of the denture wearer and would enable effective and accurate correction of the accumulated errors in the jaw relationship in a stable working environment. This technique should be performed if a patient has poor masticatory function or occlusion-related complaints. However, performing a clinical remount on dentures with an excessive anterior–posterior discrepancy between the centric relation and the maximal intercuspal position or on dentures with extremely low occlusal vertical dimension, is considered less effective. The clinical remount procedure remains an essential skill both for fabricating quality dentures and maintaining those already in service.

The preventive care of medication-related osteonecrosis of the jaw (MRONJ): a position paper by Italian experts for dental hygienists

PURPOSE

The prevention and early diagnosis of medication-related osteonecrosis of the jaw (MRONJ) is fundamental to reducing the incidence and progression of MRONJ. Many in the field believe that dental hygienists should play an integral role in primary and secondary MRONJ prevention. However, to date, very few publications in the literature have proposed standardised MRONJ protocols, which are dedicated to dental hygienists. The aim of this study was to provide guidance to the health care providers managing MRONJ.

METHODS

The expert opinion in this study was developed by dental hygienists from the main Italian technical-scientific associations (Italian Dental Hygienists Association, AIDI and National Union of Dental Hygienists, UNID) and authors of the latest Italian recommendations regarding MRONJ from the field of dentistry and maxillofacial surgery.

RESULTS

The oral care protocol outlined in this position paper is focused on the role of dental hygienist in patients at risk or affected by MRONJ, and it regards 3 main issues: primary prevention, secondary prevention and supporting the treatment of MRONJ. Each issue contains easy-to-apply indications and procedures, as described by the authors, regarding the role of the dental hygienist.

CONCLUSION

Referring to the main issues under consideration (primary prevention, secondary prevention and the treatment of MRONJ), a clinical examination of periodontal tissue is critical in preventing MRONJ. It is the opinion of the authors of this study that the application of a periodontal screening score is fundamental in defining personalised strategies for patients at risk of MRONJ. By means of these basic procedures, a protocol for assisting the health care provider and the presentation of a practical approach for patients at risk or affected by MRONJ are described in this study.

Incidence and risk factors for non-adaptation of new mandibular complete dentures: a clinical trial

OBJECTIVE

To investigate the incidence and risk factors for non-adaptation of the conventional mandibular complete denture (CMCD).

MATERIALS AND METHODS

A total of 108 edentulous patients were rehabilitated with complete dentures (CDs) and followed up at 3- and 6-month intervals. Adaptation was confirmed based on chewing, phonetics, and comfortable swallowing with the CDs. The risk factors among sociodemographic and patient-centered factors were analyzed. Statistical analyses included the chi-square test and then a multivariate analysis.

RESULTS

After 3 months, 38.0% of patients showed non-adaptation to CMCDs. Non-adaptation was significantly associated with the absence of previous mandibular denture experience (p = 0.042), ulcerations after 15 days of rehabilitation (p < 0.001), and a reduced posterior mandibular ridge (p = 0.035). After 6 months, this incidence decreased to 14.1%. The factors associated with non-adaptation were ulcerative lesions after 15 (p < 0.001) and 30 (p < 0.001) days of the delivery of CDs and the non-regular use of mandibular CDs (p < 0.001).

CONCLUSION

The incidence of non-adaptation was higher after 3 months, with reduction after 6 months. Sociodemographic variables did not influence the adaptation. After 3 months, the absence of previous experience, traumatic ulcers, and reduced mandibular ridges hindered the adaptation of patients to mandibular CDs. After 6 months, only the occurrence of ulcerative lesions and non-regular wear of dentures were risk factors for non-adaptation.

CLINICAL RELEVANCE

A considerable number of patients have difficulties in adapting to the mandibular dentures. Identifying the factors of non-adaptation of the dentures will contribute to increasing the predictability of this critical adaptation period.

Computer-Aided Design and Computer-Aided Manufacturing (CAD/CAM) Complete Dentures for Atrophic Alveolar Ridges: Workflow Combining Conventional and Novel Techniques

Extreme residual ridge resorption is a challenging clinical situation for the fabrication of complete dental prostheses. Computer-aided design and computer-aided manufacturing (CAD/CAM) complete dentures have been shown to have superior fit and material strength to conventionally fabricated dentures, but no clinical protocols have been described for cases of extreme residual ridge resorption. This report describes a workflow combining conventional and novel techniques for CAD/CAM complete dentures fabrication for atrophic alveolar ridges and demonstrates that a CAD/CAM workflow is an effective tool for solving this complex situation.

Evaluation of the time-dependent efficacy of commercial denture or orthodontic appliance cleansers: An in vitro study

The aim of this study was to evaluate the antimicrobial, stain and protein removal efficacy of denture or orthodontic appliance cleansers using in vitro test methods. Experimental cleansers were applied for experimental time in each evaluation method. To evaluate the microorganism removal efficacy, C. albicans and S. mutans removal rate was calculated from the specimen surface. Stain and protein removal rate was calculated using the spectrophotometer. Experimental cleansers significantly affected the microorganism removal rate for both C. albicans and S. mutans, as well as the stain and protein removal rates, at each experimental time (p<0.05). As the application time increased, the stain and protein removal rates of all experimental cleansers significantly increased (p<0.05). The present study provided in vitro evaluation methods to assess the efficacy of denture or orthodontic appliance cleansers. Also, manufacturers and researchers can predict clinical outcomes and ensure proper hygiene management of dentures or orthodontic appliances.

A simulation model used in teaching denture border adjustment: Randomized controlled trial

OBJECTIVES

The goal was to propose a new simulation model as a training tool in complete denture (CD) flange adjustment and to evaluate if the model can improve student competencies in different learning domains.

METHODS

Fourth-year undergraduate dental students (n = 100) were equally divided into control and test groups. Both groups received didactic instructions for CD post-insertion procedures, but the test group had additional simulation training using modified working casts. Both groups then performed CD flange adjustment on real patients, and their skills were evaluated using a specific checklist. The data were assessed by independent samples t-test and a chi-square test at α = 0.05.

RESULTS

The students in the test group showed significantly better overall performance (57.94%) compared with the control group (30.14%) in clinical post-insertion CD flange adjustment procedures (p < 0.001). However, the psychomotor skills of the male students in the test group were not significantly influenced (p = 0.268). Considering the competencies for different tasks, more students that were competent were present in the test group compared to those in the control group regarding most of the knowledge (p ≤ 0.012) and all of the cognitive skill tasks (p ≤ 0.021). More students were competent for half of the psychomotor skill tasks (p ≤ 0.027). However, when considering gender, the number of competent male students was significantly greater in the test group only for one of the psychomotor tasks.

CONCLUSION

The simulation model significantly improved the overall clinical skills of the students, allowing them to learn the common CD post-insertion maintenance procedures before performing the procedure clinically.

Multivariate analysis reveals oral health-related quality of life of complete denture wearers with denture adhesives: a multicenter randomized controlled trial

Purpose To investigate the difference in improvement of oral health-related quality of life (OHR-QoL) depending on the oral and denture conditions of a complete denture wearer when using a cream or powder type denture adhesive in a 10-center parallel randomized clinical trial.Methods Two hundred edentulous subjects who wore complete dentures were allocated to each of the three groups according to denture adhesive type: cream, powder, and control (saline solution). The materials were applied to the mucosal surface of the dentures for 4 days, and baseline data and data after the intervention were collected. OHR-QoL was assessed using the Japanese version of the modified Oral Health Impact Profile for Edentulous Patients (OHIP-EDENT-J) scale for outcome. Multivariate analysis was used to investigate improvements in OHR-QoL according to participant characteristics among complete denture wearers using these materials.Results OHIP-EDENT-J scores were significantly decreased in all groups after the intervention (p < 0.05); however, there were no statistically significant differences among the groups. Multiple logistic regression analysis revealed a significant association between the vertical height of the maxillary and mandibular alveolar ridge and OHIP-EDENT-J scores in the cream-type denture adhesive group. In contrast, there were no significant association between participant characteristics and OHIP-EDENT-J scores in the powder-type adhesive and control groups.Conclusions The use of denture adhesives could improve OHR-QoL for complete denture wearers. The cream-type denture adhesives may be expected to improve OHR-QoL in patients with poor residual ridge conditions compared with patients with good residual ridge conditions.

Remote Management of Prosthodontic Emergencies in the Geriatric Population During the Pandemic Outbreak of COVID-19

The global pandemic outbreak of coronavirus disease 2019 (COVID-19) has put the world in a panic situation. It has been evident that the geriatric population is more susceptible to acquire this infection. Thus, due to this ongoing crisis, geriatric individuals cannot visit a dental operatory, and there is the possibility of their dental needs and emergencies to remain unattended. Partial or complete edentulism is very prevalent among the geriatric population, and prosthodontic management of these patients is essential for their well-being. However, the prosthesis can lead to various emergencies of the oral and its supporting structures. There are currently no available recommendations to address these prosthodontic emergencies in geriatric individuals during this pandemic period. Hence, the aims of this minireview were to discuss the common prosthodontic emergencies in the geriatric population and provide recommendations to manage these issues during the COVID-19 pandemic outbreak.

Trueness of Intaglio Surface of Milled Digital Dentures Designed from Intraoral Scans

PURPOSE

To asses trueness of the intaglio surface of milled dentures fabricated according to a fully digital protocol starting from intraoral scans in a clinical study by means of 3-dimensional (3D) digital analysis.

MATERIALS AND METHODS

Ten maxillary and 10 mandibular dentures, designed from intraoral scans and milled in-house, were studied. Intraoral scans were compared with the scans of intaglio surface of milled dentures. To this end, they were aligned, trimmed and used in a metrology software to measure their mean 3D distance, absolute mean deviation, and other parameters. Measured differences for all parameters were statistically investigated. Subgroup analysis for the maxillary and mandibular dentures was performed using independent samples t-test or, in case of non-normal distribution, by means of Mann-Whitney test.

RESULTS

Using a mean of 24.9 ±2.8 measurement points/mm² , a mean 3D distance of 0.0006 ±0.007 mm between intraoral scans and the scans of the intaglio surface of milled dentures was measured. The corresponding absolute mean deviation was 0.055 ±0.032 for maxillary dentures and 0.061 ±0.016 for mandibular dentures; such a difference between arches was statistically significant (p = 0.035).

CONCLUSIONS

Milled dentures fabricated using a fully digital protocol and intraoral scans have accurate intaglio surfaces. It is reasonable to assume that they may achieve an adequate fit.

Color Stability and Surface Properties of PMMA/ZrO2 Nanocomposite Denture Base Material after Using Denture Cleanser

Objectives

This study aimed to evaluate denture cleanser effects on color stability, surface roughness, and hardness of PMMA denture base resin reinforced with nano-ZrO₂.

Materials and Methods

A total of 420 specimens were fabricated of unreinforced and nano-ZrO₂ reinforced acrylic resin at 2.5% and 5%, resulting in 3 main groups. These groups were further subdivided (n = 10) according to immersion solution (distilled water, Corega, sodium hypochlorite, and Renew) and immersion duration. Surface roughness, hardness, and color were measured at baseline (2 days-T₀) in distilled water and then after 180 and 365 days of immersion (T₁ & T₂) in water or denture cleansing solutions. Data was collected and analyzed using two-way ANOVA followed by Bonferroni post hoc test (α = 0.05).

Results

Surface roughness increased significantly after denture cleanser immersion of unmodified and nano-ZrO₂-modified PMMA materials while hardness decreased (P < 0.001). The denture cleansers significantly affected the color of both PMMA denture bases (P < 0.001). The immersion time in denture cleansers significantly affected all tested properties (P < 0.001). Within denture cleansers, NaOCl showed the highest adverse effects (P < 0.05) while Renew showed the least adverse effects.

Conclusion

Denture cleansers can significantly result in color change and alter the surface roughness and hardness of denture base resin even with ZrO₂ nanoparticles addition. Therefore, they should be carefully used.

Pneumonia prevention in the elderly patients: the other sides

Pneumonia is one of the leading causes of morbidity and mortality from infection in elderly patients. The increased frequency of pneumonia among elderly subjects can be explained by the physiological changes linked to the progressive aging of the respiratory tree and the diminished immunological response. A spiral of event leads to frailty, infection and possible death; preventing pneumonia consists of controlling the risk factors. Dysphagia, which is associated with malnutrition and dehydration, is recognized as one of the major pathophysiological mechanism leading to pneumonia and its screening is crucial for the pneumonia risk assessment. The impairment in the oropharyngeal reflexes results in stagnation of foreign material in the lateral cavities of the pharynx which may then get aspirated repeatedly in the lungs and cause pneumonia. Pneumonia prevention starts with lifestyle modifications such as alcohol and tobacco cessation. A careful review of the risk-benefit of the prescribed medication is critical and adaptation may be required in elders with multiple morbidities. Respiratory physiotherapy and mobilization improve the functional status and hence may help reduce the risk of pneumonia. Maintaining teeth and masticatory efficiency is important if malnutrition and its consequences are to be avoided. Daily oral hygiene and regular professional removal of oral biofilm can prevent the onset of periodontitis and can avoid an oral environment favoring the colonization of respiratory pathogens than can then be aspirated into the lungs.

Removal of denture adhesives from PMMA and Polyamide denture base materials

Denture adhesives need complete removal due to their frequent replacement.

Immediate vs conventional loading of mandibular overdentures: A comprehensive systematic review and meta-analysis of randomized controlled trials

Clinicians treating overdenture patients need to know if immediate loading and conventional loading results in similar outcomes. This study aimed to perform a systematic literature search of studies comparing immediate and conventional loading of mandibular overdentures irrespective of the number of implants and conduct a meta-analysis of implant failure and marginal bone loss (MBL). A literature search of PubMed, ScienceDirect, Ovoid, Springer, and Google Scholar databases was performed for randomized controlled trials (RCTs) comparing immediate vs conventional loading of mandibular overdentures. The primary outcome was implant failure and the secondary outcome was marginal bine loss (MBL). A descriptive analysis was performed for other outcomes. Thirteen trials were included. Only one trial compared the immediate and delayed loading of single implant-supported overdenture. Seven trials used two implants, one trial used three implants while four trials used four implants. Meta-analysis indicated no statistically significant difference in implant failure and MBL between immediate and conventional loading of two-implant and four-implant supported overdentures. Descriptive analysis indicated no difference in peri-implant tissue indices, implant stability, and quality of life outcomes between the two loading protocols.There may be no difference in implant failure and MBL with immediate loading or conventional loading of two and four-implant supported mandibular overdentures. Literature review indicates that there may be no difference in peri-implant tissue indices, implant stability, and QoL outcomes between the two loading protocols. The overall quality of evidence is moderate. Further, adequately powered RCTs are required to strengthen the evidence.

Cinnamaldehyde is a biologically active compound for the disinfection of removable denture: blinded randomized crossover clinical study

BACKGROUND

Fungal infections associated with the use of dentures, like denture stomatitis, are difficult to prevent and treat. This in situ study aimed to investigate the efficacy of cinnamaldehyde for the disinfection of complete removable dentures, and the effect on the physical and mechanical properties (Vickers microhardness, color, and surface roughness) of the acrylic resin.

METHODS

Acrylic resin disks were inserted into the dentures of a probabilistic sample of 33 complete denture users, that used cinnamaldehyde (27 μg/mL) and 0.5% sodium hypochlorite solutions in a 20 min/7-days protocol of dentures immersion in each solution, with a wash-out period of 7 days, to constitute a crossover-study. The disks were analyzed before and after the immersion, for the presence of microorganisms (CFU/mL) and by scanning electron microscope (SEM). Also, the surface roughness (Ra) and Vickers microhardness were measured, and color parameters were analyzed using the National Bureau of Standards (NBS) method. Data was analyzed by Wilcoxon and Friedman (microbiological evaluation), paired t-test (color and roughness) and independent t-test (Vickers hardness) (α = 0.05).

RESULTS

A significant reduction (P < 0.05) in the number of microorganisms was observed for each species (total microorganisms, Streptococcus mutans, and Candida spp.), with no significant differences (P > 0.05) between hypochlorite and cinnamaldehyde. There was an increase in the roughness and a decrease in the hardness of the test specimens, with no difference between the two disinfectant substances (P > 0.05). Both hypochlorite and cinnamaldehyde also caused changes in color, considered as "perceptible" by the NBS classification, but with no significant difference between disinfectant substances (P < 0.05), and under the clinically acceptable limit (ΔE ≤ 3.7).

CONCLUSION

The 27 μg/mL cinnamaldehyde solution was effective against all evaluated microorganisms and caused minor alterations in hardness, surface roughness, and color parameters, with no clinical relevance.

A Dental Response to the COVID-19 Pandemic-Safer Aerosol-Free Emergent (SAFER) Dentistry

Dental services are significantly impacted by the COVID-19 pandemic. Almost all dental procedures carry a high infection risk for providers and patients due to the spread of aerosols. As a consequence, public health agencies and professional associations have issued guidelines for enhanced infection control and personal protection equipment and have also limited care to urgent or emergency services. However, there is no dental service concept for pandemic disaster preparedness or response that might be applied. Moreover, pathways to dental care provision in a post-pandemic future with persisting risks are needed. We propose Safer Aerosol-Free Emergent Dentistry (SAFER Dentistry) as one approach to dental services during and emerging from the pandemic. The concept's starting point is the identification of the most common patient needs. The next step is to replace common treatments addressing the most frequent needs with alternative interventions involving a lower infection risk because they do not generate aerosols. SAFER Dentistry is innovative, avoids risk, and responds to the requirements of a pandemic and post-pandemic emergency where the risk of airborne disease transmission remains high. SAFER Dentistry thereby ensures continuity of dental services while protecting providers and patients from infectious pathogens. Moreover, SAFER Dentistry allows dental service providers to remain operational and generate income even under pandemic conditions. Potential implementation and policy options for SAFER Dentistry include universal availability without co-payments by patients and a uniform bundled payment scheme for providers to simplify budgeting, reimbursement, and administration during a pandemic. Adaptations and adjustments of the concept are possible and encouraged as long as the principle of avoiding aerosol-generating procedures is maintained.

Number of natural teeth, denture use and mortality in Chinese elderly: a population-based prospective cohort study

BACKGROUND

The associations between the number of natural teeth/denture use and all-cause mortality remain unclear due to lake of investigation for the potential interaction between tooth loss and denture use and for the potential changes in these exposures over time in older adults. We undertake this study to evaluate the associations of the number of natural teeth and/or denture use with mortality in Chinese elderly.

METHODS

This is a prospective cohort study of 36,283 older adults (median age: 90). The number of natural teeth and denture use were collected with structured questionnaire. We evaluated hazard ratios (HRs) and confidence intervals (CIs) using a Cox proportional hazards model adjusting for demographic factors, education, income, lifestyle factors, and comorbidities.

RESULTS

We documented 25,857 deaths during 145,947 person-years of observation. Compared to those with 20+ teeth, tooth loss was associated with a gradual increase in mortality, with an adjusted HR of 1.14 (95% CI, 1.06 to 1.23) for those with 10-19 teeth, 1.23 (95% CI, 1.15 to 1.31) for those with 1-9 teeth, and 1.35 (95% CI, 1.26 to 1.44) for those without natural teeth. Denture use was associated with lower risk of mortality (adjusted HR 0.81; 95% CI, 0.77 to 0.84). Subgroup analyses indicated that the benefit of denture use was greater in men than in women (P = 0.02) and tended to decrease with age (P < 0.001). The effects of denture use did not differ among various degrees of tooth loss (P = 0.17).

CONCLUSIONS

Tooth loss was associated with an increased risk of mortality in older adults. Denture use provided a protective effect against death for all degrees of tooth loss however, this effect appeared to be modified by sex and age.

Evaluation and Comparison of the Effects of Persulfate Containing and Persulfate-free Denture Cleansers on Acrylic Resin Teeth Stained with Cigarette Smoke: An In Vitro Study

Problem statement and aim 

The esthetics of the complete denture primarily depend upon the color of the denture teeth; however, there are situations where the teeth are subjected to extrinsic and intrinsic stains and discolor over time. The purpose of the study was to investigate the effects of smoking and two different denture cleaners on the color stability of the denture teeth.

Material and methods

Commercially available maxillary anterior teeth made up of acrylic resin were selected for the study and were divided into two groups (n=10): persulfate-free denture cleanser and persulfate containing denture cleansers. The acrylic teeth were set in the smoke chamber with a distance to absorb the smoke equally from the cigarette. The smoke was released for 10 minutes, and the results are observed by the spectrophotometer.

Results

All the values were collected after the 21^st day, and data were analyzed with the SPSS software. It was found that denture cleansers with persulfate are effective on color stability. 

Conclusions

Even though the persulfate containing denture cleansers are injurious to health, they can be recommended to the smokers with clear instructions of use. However, for non-smokers, persulfate-free denture cleansers are preferred over the persulfate containing denture cleansers.

The antimicrobial and antibiofilm properties of allicin against Candida albicans and Staphylococcus aureus - A therapeutic potential for denture stomatitis

The objective of this study is to determine the therapeutic efficacy of allicin against Candida albicans (C. albicans) and Staphylococcus aureus (S. aureus), the common etiological agents for denture stomatitis (DS). The minimum inhibitory concentration (MICs), minimum bactericidal concentrations (MBCs) and minimum fungicidal concentration (MFCs) of allicin were determined by the broth microdilution method followed by checkerboard microdilution method for a synergistic interaction between allicin + nystatin and allicin + CHX. The potential of allicin to eradicate C. albicans and S. aureus biofilms was assessed by treating biofilm formed on self- polymerized acrylic resin with allicin at a sub-MIC concentration for 5 min. The commercial denture cleanser (brand X) was used as a positive control. A Kruskal-Wallis test followed by the post-hoc Mann-Whitney U test was applied (SPSS 20.0), and the level of significance was set at P < 0.05. Allicin exhibited antimicrobial activity against C. albicans (MIC:8 µg/ml and MFC:16 µg/ml) and S. aureus (MIC:8 µg/ml and MBC:8 µg/ml). A synergistic interaction was observed between allicin + nystatin and allicin + CHX (FICI ≤ 0.5). Allicin exhibited significant biofilm eradication against C. albicans and S. aureus biofilms with percentages of 50.0% and 52.6%, respectively. The results of this study suggest a possible application of allicin in treating C. albicans and S. aureus infection in DS.

The relationship of oral mucosal lesions and removable prostheses: Quantitative and qualitative study

Background/Aim: The aim of this study was to determine the development and distribution of denture-related oral mucosal lesions in patients using removable prosthesis by using quantitative and qualitative research methods. Material and Methods: A 21-item structured questionnaire form was used. Then, patients were evaluated for the presence and types of oral lesions. In the qualitative phase of the study, two focus group interviews were conducted with volunteers among participants of the quantitative part. The quantitative data were first evaluated by the Kolmogorov-Smirnov test for normal distribution. Chi-square test, Mann Whitney U test, t-test and logistic regression were used for statistical evaluation. Qualitative data analysis was manually performed by the content analysis method. Results: This study included 171 subjects. When the participants were classified as lesion and non-lesion groups, cigarette use and duration of prosthesis use were higher in patients with lesions. Denture-related lesions occurred in 46.2% of the participants; prosthetic stomatitis in 23.9% of the denture-related lesions, traumatic ulcer in 12.9%, epulis fissuratum in 9.9%, and angular cheilitis in 5.8%. Of the participants with lesions 72% (n=57) had a single lesion, while 28% (n=22) had multiple lesions. The duration of prosthesis use was longer in patients with lesions (p=0.022). The main themes determined in the qualitative stage were identified as "views on prosthesis use", "features related to prosthesis care", "information sources on prosthesis" and "proposals of participants". Conclusions: Current study shows that denture-related lesions are very common. Patients should be informed in detail and adequately by physicians and specialized nurses in this regard at every stage of treatment. A universal protocol will be very helpful to ensure that patients are provided with all necessary information about wearing dentures, their maintenance and the importance of regular check-ups. Informative meetings should be organized for wider patient groups in which patients may also interactively participate in, and studies to increase oral health literacy should be conducted. The cross-sectional assessment is not enough for risk assessment due to its nature and only declaration based assessment might miss the relations. Follow-up studies combined with qualitative studies with different approaches are needed.

A randomised bite force study assessing two currently marketed denture adhesive products compared with no-adhesive control

Unlike other oral care products, there are limited technologies in the denture adhesive category with the majority based on polymethyl vinyl ether/maleic anhydride (PVM/MA) polymer. Carbomer-based denture adhesives are less well studied, and there are few clinical studies directly comparing performance of denture adhesives based on different technologies. This single-centre, randomised, three-treatment, three-period, examiner-blind, crossover study compared a carbomer-based denture adhesive (Test adhesive) with a PVM/MA-based adhesive (Reference adhesive) and no adhesive using incisal bite force measurements (area over baseline over 12 hr; AOB0-12) in participants with a well-made and at least moderately well-fitting complete maxillary denture. Eligible participants were randomised to a treatment sequence and bit on a force transducer with increasing force until their maxillary denture dislodged. This procedure was performed prior to treatment application (baseline) and at 0.5, 1, 3, 6, 9, and 12 hr following application. Forty-four participants were included in the modified intent-to-treat population. AOB0-12 favoured both Test adhesive to No adhesive (difference: 2.12 lbs; 95% CI [1.25, 3.00]; p < 0.0001) and Reference adhesive to No adhesive (difference: 2.76 lbs; 95% CI [1.89, 3.63]; p < 0.0001). There was a numerical difference in AOB0-12 for Test versus Reference adhesive (-0.63 lbs; [-1.51, 0.25]); however, this was not statistically significant (p = 0.1555). Treatments were generally well tolerated. Both PVM/MA and carbomer-based denture adhesives demonstrated statistically significantly superior denture retention compared with no adhesive over 12 hr, with no statistically significant difference between adhesives.

Grapefruit seed extract effectively inhibits the Candida albicans biofilms development on polymethyl methacrylate denture-base resin

This study aimed to investigate the cleansing effects of grapefruit seed extract (GSE) on biofilms of Candida albicans (C. albicans) formed on denture-base resin and the influence of GSE on the mechanical and surface characteristics of the resin. GSE solution diluted with distilled water to 0.1% (0.1% GSE) and 1% (1% GSE) and solutions with Polident® denture cleansing tablet dissolved in distilled water (Polident) or in 0.1% GSE solution (0.1% G+P) were prepared as cleansing solutions. Discs of acrylic resin were prepared, and the biofilm of C. albicans was formed on the discs. The discs with the biofilm were treated with each solution for 5 min at 25°C. After the treatment, the biofilm on the discs was analyzed using a colony forming unit (CFU) assay, fluorescence microscopy, and scanning electron microscopy (SEM). In order to assess the persistent cleansing effect, the discs treated with each solution for 5 min were aerobically incubated in Yeast Nitrogen Base medium for another 24 h. After incubation, the persistent effect was assessed by CFU assay. Some specimens of acrylic resin were immersed in each solution for 7 days, and changes in surface roughness (Ra), Vickers hardness (VH), flexural strength (FS), and flexural modulus (FM) were evaluated. As a result, the treatment with 1% GSE for 5 min almost completely eliminated the biofilm formed on the resin; whereas, the treatment with 0.1% GSE, Polident, and 0.1% G+P for 5 min showed a statistically significant inhibitory effect on biofilms. In addition, 0.1% GSE and 0.1% G+P exerted a persistent inhibitory effect on biofilms. Fluorescence microscopy indicated that Polident mainly induced the death of yeast, while the cleansing solutions containing at least 0.1% GSE induced the death of hyphae as well as yeast. SEM also revealed that Polident caused wrinkles, shrinkage, and some deep craters predominantly on the cell surfaces of yeast, while the solutions containing at least 0.1% GSE induced wrinkles, shrinkage, and some damage on cell surfaces of not only yeasts but also hyphae. No significant changes in Ra, VH, FS, or FM were observed after immersion in any of the solutions. Taken together, GSE solution is capable of cleansing C. albicans biofilms on denture-base resin and has a persistent inhibitory effect on biofilm development, without any deteriorations of resin surface.

Impact of frequency of denture cleaning on microbial and clinical parameters - a bench to chairside approach

Objective: Robust scientific and clinical evidence of how to appropriately manage denture plaque is lacking. This two-part study (i) developed an in vitro model of denture plaque removal, and (ii) assessed effectiveness of these approaches in a randomised clinical trial.

Method: (i) a complex denture plaque model was developed using the dominant microbial genera from a recent microbiome analyses. Biofilms formed on polymethylmethacrylate were brushed daily with a wet toothbrush, then either treated daily for 5 days or only on Days 1 and 5 with Polident® denture cleanser tablets (3 min soaking). Quantitative and qualitative microbiological assessments were performed. (ii), an examiner-blind, randomised, crossover study of complete maxillary denture wearers was performed (n = 19). Either once-daily for 7 days or on Day 7 only, participants soaked dentures for 15 min using Corega® denture cleansing tables, then brushed. Denture plaque microbiological assessment used sterilized filter paper discs.

Results: The in vitro model showed daily cleaning with denture cleanser plus brushing significantly reduced microbial numbers compared to intermittent denture cleaning with daily brushing (p < 0.001). The clinical component of the study showed a statistically significant reduction in denture plaque microbial numbers in favour of daily versus weekly treatment (aerobic bacteria p = 0.0144). Both in vitro and in vivo studies showed that denture plaque biofilm composition were affected by different treatment arms.

Conclusions: This study demonstrated that daily denture cleansing regimens are superior to intermittent denture cleansing, and that cleansing regimens can induce denture plaque compositional changes. Clinicaltrials.gov registration: NCT02780661.

Combined effects of new complete denture fabrication and simplified dietary advice on nutrient intake in edentulous elderly patients for 6 months

OBJECTIVE

The aim was to evaluate the combined effects of a new complete denture fabrication and simple dietary advice (using unique pamphlets) by dentists on nutrient intake in edentulous elderly patients.

MATERIALS AND METHODS

A randomized controlled trial was performed on edentulous elderly patients who were randomly allocated to either an intervention or a control group. The intervention group received a new complete denture and simple dietary advice, whereas the control group received a new complete denture and denture care advice. The outcomes of this trial (nutrient intakes) were calculated using a brief-type self-administered diet history questionnaire (BDHQ) and assessed at three time points (pretreatment and 3 and 6 months post-treatment).

RESULTS

At 3 months post-treatment, the intake of several nutrients such as proteins (p = 0.004), magnesium (p < 0.001), and vitamin B1 (p = 0.014) was significantly higher in the intervention group than the control group, whereas at 6 months post-treatment, plant protein (p = 0.028) intake was significantly higher in the intervention group than the control group. On the contrary, animal protein (p = 0.049) and vitamin B12 (p = 0.028) intakes were significantly higher in the control group.

CONCLUSIONS

New complete denture fabrication with simple dietary advice might improve nutrient intake in elderly edentulous patients; however, the effect is probably short term.

CLINICAL SIGNIFICANCE

New complete denture fabrication along with simple dietary advice by dentists might improve nutrient intake in edentulous elderly patients. Therefore, regular use of these interventions in the dental setting might have long-term effects on nutrient intake in elderly edentulous patients.

TRIAL REGISTRATION

UMIN-CTR Clinical Trial, unique trial number: UMIN000017879.

Chemical hygiene protocols for complete dentures: A crossover randomized clinical trial

STATEMENT OF PROBLEM

Clinical evidence on the best chemical protocol for the disinfection and removal of biofilm from complete dentures is lacking.

PURPOSE

The purpose of this crossover randomized clinical trial was to assess the effectiveness of various chemical hygiene clinical protocols in reducing the microbial viability of biofilm formed on complete dentures.

MATERIAL AND METHODS

In this triple-blind (participants, dentist, and outcome evaluator) study, complete denture wearers without candidiasis were randomly divided into 4 groups (n=40) according to the chemical hygiene protocol: water (placebo), 0.5% sodium hypochlorite solution, 0.12% chlorhexidine gluconate solution, and 5% sodium bicarbonate solution. The biofilm formed on the palate intaglio and denture teeth was collected and assessed in each experimental phase for quantitative microbial viability at the seventh and 14th day after using the chemical protocol.

RESULTS

Two participants were lost. Data were analyzed by MANOVA and Tukey HSD tests. Soaking dentures was not effective in decreasing Candida albicans, C. non-albicans, and lactobacillus counts. The use of sodium hypochlorite and chlorhexidine decreased total microorganisms and Streptococcus mutans counts for both palate and teeth compared with water and sodium bicarbonate. The intaglio of the dentures always presented higher microbial counts than did the denture teeth.

CONCLUSIONS

The use of sodium hypochlorite and chlorhexidine and mechanical cleansing with a toothbrush decreased microbial viability in healthy complete denture wearers.

Randomised clinical trial: Efficacy of strategies to provide oral hygiene activities to nursing home residents with dementia who resist mouth care

OBJECTIVES

The purpose of this study was to test the efficacy of MOUTh (Managing Oral Hygiene Using Threat Reduction), a nonpharmacologic, relationship-based intervention vs. control on 2 primary outcomes for nursing home (NH) residents with dementia who resisted mouth care: (i) reduction in the occurrence and intensity of care-resistant behaviours (CRBs) and (ii) improvement in oral health. Two secondary outcomes were also examined: (i) the duration of mouth care and (ii) the completion of oral hygiene activities.

BACKGROUND

Persons with dementia who exhibit CRBs are at risk for inadequate mouth care and subsequent systemic illnesses.

MATERIALS AND METHODS

The study used a randomised repeated measures design. Recruitment occurred in 9 nursing homes that varied in size, ownership, reimbursement patterns and location. One hundred and one nursing home residents with dementia were randomised at the individual level to experimental (n = 55) or control groups (n = 46). One hundred participants provided data for the analyses.

RESULTS

Compared to the control group, persons in the experimental group had twice the odds of allowing mouth care and completing oral hygiene activities; they also allowed longer duration of mouth care (d = 0.56), but showed only small reductions in the intensity of CRBs (d = 0.16) and small differential improvements in oral health (d = 0.18).

CONCLUSION

The data suggest that this intervention facilitates mouth care among persons with dementia. The management of refusal behaviour may be a clinically more realistic approach than reducing or eradicating refusals.

Microbial evaluation of the effectiveness of different methods for cleansing clear orthodontic retainers: A randomized clinical trial

OBJECTIVE

To compare effectiveness of brushing an Essix retainer with water only and brushing followed by soaking in one of three commercial cleansing tablets.

MATERIALS AND METHODS

A double-blind, parallel, randomized clinical trial with a split-mouth design was completed with 60 volunteers with specific eligibility criteria assigned to three groups to compare the cleansing effectiveness of brushing an Essix retainer with water only, followed by soaking in one of three alkaline peroxide-based commercial cleansing tablets (Retainer Brite®, Kukis®, and Corega®). Each participant wore an upper Essix retainer (with an electronic microsensor) on a full-time basis for 14 days and used one of the three products on one side of the retainer for 15 min/d. The effectiveness of the cleansing tablets was tested by the scanning electron microscopy, bacterial identification, bacterial quantification, and disk diffusion methods.

RESULTS

Bacterial quantification tests demonstrated nonsignificant statistical differences between the control and test sides of the three cleansing tablets: Retainer Brite®, Kukis®, and Corega® (Mann-Whitney test P-values were .6, .37, and .5, respectively). A Kruskal-Wallis test also showed nonstatistical difference in the bacterial counts between the three groups (P-value = .5). In vitro tests showed a minimal inhibition zone of Staphylococcus epidermidis only with Corega® tablets.

CONCLUSIONS

Using chemical cleansing tablets after mechanical cleansing did not significantly reduce the bacterial count in Essix retainers when compared to use of mechanical cleansing alone. However, the tablets seem to be effective against "cocci" bacterial species.

Efficacy of Propolis on the Denture Stomatitis Treatment in Older Adults: A Multicentric Randomized Trial

Our hypothesis tested the efficacy and safety of a mucoadhesive oral gel formulation of Brazilian propolis extract compared to miconazole oral gel for the treatment of denture stomatitis due to Candida spp. infection in older adults. Forty patients were randomly allocated in a noninferiority clinical trial into two groups. The control group (MIC) received 20 mg/g miconazole oral gel and the study group (PROP) received mucoadhesive formulation containing standardized extract of 2% (20 mg/g) propolis (EPP-AF®) during 14 days. Patients were examined on days 1, 7, and 14. The Newton's score was used to classify the severity of denture stomatitis. The colony forming unity count (CFU/mL) was quantified and identified (CHROMagar Candida®) before and after the treatment. Baseline characteristics did not differ between groups. Both treatments reduced Newton's score (P < 0.0001), indicating a clinical improvement of the symptoms of candidiasis with a clinical cure rate of 70%. The microbiological cure with significant reduction in fungal burden on T14 was 70% in the miconazole group and 25% in the EPP-AF group. The EPP-AF appears to be noninferior to miconazole considering the clinical cure rate and could be recommended as an alternative treatment in older patients.

Maturation of the MOUTh Intervention: From Reducing Threat to Relationship-Centered Care

The purpose of the current article is to describe a personalized practice originally conceived as a way to prevent and minimize care-resistant behavior to provide mouth care to older adults with dementia. The original intervention, Managing Oral Hygiene Using Threat Reduction Strategies (MOUTh), matured during the clinical trial study into a relationship-centered intervention, with emphasis on developing strategies that support residents' behavioral health and staff involved in care. Relationships that were initially pragmatic (i.e., focused on the task of completing mouth care) developed into more personal and responsive relationships that involved deeper engagement between mouth care providers and nursing home (NH) residents. Mouth care was accomplished and completed in a manner enjoyable to NH residents and mouth care providers. The MOUTh intervention may also concurrently affirm the dignity and personhood of the care recipient because of its emphasis on connecting with older adults.

Effects of Denture Cleansers on Heat-Polymerized Acrylic Resin: A Five-Year-Simulated Period of Use

This study evaluated color stability, surface roughness and flexural strength of acrylic resin after immersion in alkaline peroxide and alkaline hypochlorite solutions, simulating a five-year-period of use. Sixty disc-shaped (16 x 4 mm) and 60 rectangular specimens (65 x 10 x 3.3 mm) were prepared from heat-polymerized acrylic resin (Lucitone 550) and assigned to 3 groups (n = 20) of immersion (20 min): C1: distilled water; AP: warm water and one alkaline peroxide tablet; SH: 0.5% NaOCl solution. Color data (∆E) were determined by a colorimeter and also quantified according to the National Bureau of Standards units. A rugosimeter was used to measure roughness (μm) and the flexural strength (MPa) was measured using a universal testing machine. Data were evaluated by Kruskal-Wallis followed by Dunn tests (color stability and surface roughness) and by one-way ANOVA and Bonferroni test (flexural strength). For all tests was considered α = 0.05. AP {0.79 (0.66;1.42)} caused color alteration significantly higher than C1 {0.45 (0.37;0.57)} and SH {0.34 (0.25;0.42)}. The mean ∆Ε values quantified by NBS were classified as "trace" for C1 (0.43) and SH (0.31) and "slight" for AP (0.96). SH {-0.015 (-0.023;0.003)} caused significantly higher ΔRa than the C1 {0.000 (-0.004;0.010)} and AP {0.000 (-0.009;0.008)} groups. There was no statistically significant difference among the solutions for flexural strength (C1: 84.62 ± 16.00, AP: 85.63 ± 12.99, SH: 84.22 ± 14.72). It was concluded that immersion in alkaline peroxide and NaOCl solutions simulating a five-year of 20 min daily soaking did not cause clinically significant adverse effects on the heat-polymerized acrylic resin.

Effects of various denture cleansers on surface roughness of hard permanent reline resins

The aim of this study was to investigate the influence of denture cleansers on surface roughness (Ra, µm) of two hard permanent reline resins and a conventional acrylic denture base resin. Fifty specimens of each material, measuring 10 mm×2 mm were randomly divided into 1 control and 4 experimental subgroups (n=10). Surface roughness values were measured using profilometer before and after immersion in distilled water and in 4 different denture cleansers for 8 h for 140 days. The Kruskal Wallis and Wilcoxon Signed Ranks tests were used for comparison among groups with a significance level of α=0.05. Immersion in denture cleansers significantly increased the surface roughness of reline resins and the difference among the cleansers was statistically significant (p=0.059). Denture cleansers can cause significant surface roughness alterations on hard permanent reline resins and denture base resin where their effect may differ according to the selected resin material.

Alkaline Peroxides Versus Sodium Hypochlorite for Removing Denture Biofilm: a Crossover Randomized Trial

This study evaluated the efficacy of cleanser solutions on denture biofilm removal by a crossover randomized clinical trial. Thirty two edentulous patients were instructed to brush their dentures (specific brush and liquid soap) three times a day (after breakfast, lunch and dinner) and to soak them (≥ 8 h) in: (C) control -water; (AP): alkaline peroxide; or (SH) 0.5% sodium hypochlorite. Each solution was used for 21 days (three cycles of 7 days). At the end of each cycle, the inner surfaces of maxillary dentures were disclosed (1% neutral red) and photographed (HX1 - Sony). Areas (total and stained biofilm) were measured (Image Tool software) and the percentage of biofilm calculated as the ratio between the area of the biofilm multiplied by 100 and total surface area of the internal base of the denture. Data were compared by means of generalized estimating equation (α=5%) and multiple comparisons (Bonferroni; α=1.67%). Immersion in SH reduced biofilm (%) (8.3 ± 13.3B) compared to C (18.2 ± 14.9A) and AP (18.2 ± 16.6A). The 0.5% sodium hypochlorite solution was the most efficacious for biofilm removal. Alkaline peroxides may not lead to further biofilm removal in patients with adequate denture maintenance habits.

Occurrence and antimicrobial susceptibility of enteric rods and pseudomonads isolated from the dental prostheses biofilm

Objective:

To determine the occurrence and the in vitro antimicrobial susceptibility of enteric rods and pseudomonads from the denture biofilm of 52 subjects at the Center for Dental Specialties of Sobral/ Ceara, Brazil.

Material and Methods:

Denture biofilm was collected and samples plated on MacConkey agar. The isolated bacterial colonies were identified using the BBL Crystal enteric/non-fermenter system. Antibiotic bacterial susceptibility was assessed by the disc diffusion method of amoxicillin, amoxicillin/clavulanic acid, doxycycline, tetracycline, tobramycin, imipenem, cefotaxime, and ciprofloxacin. The Minimum Inhibitory Concentration (MIC) of cefotaxime, tobramycin, doxycycline, imipenem, and ciprofloxacin was determined for 40 species by E-test.

Results:

34 subjects (65.4%) harbored enteric rods in their prostheses. Klebsiella pneumoniae (26.5%), Escherichia coli (23.5%), and Enterobacter aerogenes (23.5%) were the most prevalent species. All organisms were susceptible to ciprofloxacin and most species were resistant to amoxicillin or amoxicillin/clavulanic acid, demonstrating variable sensitivity patterns to other antimicrobials. However, the MIC showed the emergence of strains with reduced sensitivity to ciprofloxacin (MIC90≥3 μg/ mL) and cefotaxime (MIC90≥2 μg/mL).

Conclusion:

The findings show high prevalence of nosocomial diseases-related bacterial species and low susceptibility to antimicrobial drugs. Therefore, these results imply caution against the indiscriminate use of broad spectrum antibiotics in dental practice.

Study protocol for a multi-center, randomized controlled trial to develop Japanese denture adhesive guidelines for patients with complete dentures: the Denture Adhesive Guideline trial: study protocol for a randomized controlled trial

Background

Denture adhesives, characterized as medical products in 1935 by the American Dental Association, have been considered useful adjuncts for improving denture retention and stability. However, many dentists in Japan are hesitant to acknowledge denture adhesives in daily practice because of the stereotype that dentures should be inherently stable, without the aid of adhesives. The aim of this study is to verify the efficacy of denture adhesives to establish guidelines for Japanese users. The null hypothesis is that the application of denture adhesives, including the cream and powder types, or a control (isotonic sodium chloride solution) would not produce different outcomes nor would they differentially improve the set outcomes between baseline and day 4 post-application.

Methods

This ten-center, randomized controlled trial with parallel groups is ongoing. Three hundred edentulous patients with complete dentures will be allocated to three groups (cream-type adhesive, powder-type adhesive, and control groups). The participants will wear their dentures with the denture adhesive for 4 days, including during eight meals (three breakfasts, two lunches, and three dinners). The baseline measurements and final measurements for the denture adhesives will be performed on the first day and after breakfast on the fourth day. The primary outcome is a general satisfaction rating for the denture. The secondary outcomes are denture satisfaction ratings for various denture functions, occlusal bite force, resistance to dislodgement, masticatory performance, perceived chewing ability, and oral health-related quality of life. Between-subjects comparisons among the three groups and within-subjects comparisons of the pre- and post-intervention measurements will be performed. Furthermore, a multiple regression analysis will be performed. The main analyses will be based on the intention-to-treat principle. A sample size of 100 subjects per group, including an assumed dropout rate of 10 %, will be required to achieve 80 % power with a 5 % alpha level.

Discussion

This randomized clinical trial will provide information about denture adhesives to complete denture wearers, prosthodontic educators, and dentists in Japan. We believe this new evidence on denture adhesive use from Japan will aid dentists in their daily practice even in other countries.

Trial registration

ClinicalTrials.gov NCT01712802. Registered on 17 October 2012.

Hardness, Cohesiveness, and Adhesiveness of Oral Moisturizers and Denture Adhesives: Selection Criteria for Denture Wearers

The mechanical properties of seven denture adhesives and eight oral moisturizers, all of which are commercially available, were evaluated using a texture profile analysis. A new assessment chart is proposed for the selection criteria of denture adhesive and oral moisturizers using a radar chart with three axes: hardness, cohesiveness, and adhesiveness.

Comparative assessment of the effectiveness of different cleaning methods on the growth of Candida albicans over acrylic surface

Context:

This study evaluated the efficacy of denture adhesive, cleanser, chlorhexidine, and brushing against Candida albicans biofilm developed on an acrylic surface and predicted the most effective, simple, and inexpensive way to maintain denture health, thereby preventing denture stomatitis.

Aims:

To find the best possible method for maintaining denture hygiene.

Settings and Design:

This retrospective analysis was conducted in the Guru Nanak Institute of Dental Sciences and Research, Kolkata, and this in vitro study was designed to minimize denture stomatitis among denture wearing population.

Subjects and Methods:

Sixty acrylic discs of equal dimensions after exposure to C. albicans were treated for a duration of 24 h with denture adhesive, cleanser, 0.2% chlorhexidine individually, or in combinations simulating clinical conditions dividing in six groups, ten samples each (n = 10).

Statistical Analysis Used:

After treatment, colony count was evaluated and statistically analyzed by post hoc Tukey's test and Dunnett's test to determine the most effective way of prevention.

Results:

The statistical post hoc analysis (Tukey's test and Dunnett's test) showed high significance (P < 0.0001). The group treated with adhesive showed high fungal growth compared to the control group, whereas chlorhexidine showed high potency to prevent C. albicans, whereas adhesive increased the adhesion of C. albicans to acrylic surface.

Conclusions:

Denture adhesive increases the adherence of C. albicans to denture surface. Other cleaning chemicals such as cleanser and chlorhexidine decrease the adherence. Moreover, among the all denture cleaning protocol, chlorhexidine drastically inhibit the adherence, as well as growth of C. albicans over denture surface.