The effect of denture fixatives on masticatory performance in complete denture patients

Multi-parameter viscoelastic material model for denture adhesives based on time-temperature superposition and multiple linear regression analysis

BACKGROUND

Restorative solutions designed for edentulous patients such as dentures and their accompanying denture adhesives operate in the complex and dynamic environment represented by human oral physiology. Developing material models accounting for the viscoelastic behavior of denture adhesives can facilitate their further optimization within that unique physiological environment. This study aims to statistically quantify the degree of significance of three physiological variables - namely: temperature, adhesive swelling, and pH - on denture adhesive mechanical behavior. Further, based on these statistical significance estimations, a previously-developed viscoelastic material modelling approach for such denture adhesives is further expanded and developed to capture these variables' effects on mechanical behavior.

METHODS

In this study a comparable version of Denture adhesive Corega Comfort was analysed rheologically using the steady state frequency sweep tests. The experimentally derived rheological storage and loss modulus values for the selected physiological variables were statistically analyzed using multi parameter linear regression analysis and the Pearson's coefficient technique to understand the significance of each individual parameter on the relaxation spectrum of the denture adhesive. Subsequently, the parameters are incorporated into a viscoelastic material model based on Prony series discretization and time-temperature superposition, and the mathematical relationship for the loss modulus is deduced.

RESULTS

The results of this study clearly indicated that the variation in both the storage and loss modulus values can be accurately predicted using the oral cavity physiological parameters of temperature, swelling ratio, and pH with an adjusted R2 value of 0.85. The R2 value from the multi-parameter regression analysis indicated that the predictor variables can estimate the loss and storage modulus with a reasonable accuracy for at least 85% of the rheologically determined continuous relaxation spectrum with a confidence level of 98%. The Pearson's coefficient for the independent variables indicated that temperature and swelling have a strong influence on the loss modulus, whereas pH had a weak influence. Based on statistical analysis, these mathematical relationships were further developed in this study.

CONCLUSIONS

This multi-parameter viscoelastic material model is intended to facilitate future detailed numerical investigations performed with implementation of denture adhesives using the finite element method.

Comparative effectiveness of types of denture adhesives in enhancing retention and function of complete dentures: a systematic review with network meta-analysis

OBJECTIVES

The purpose of this systematic review with network meta-analysis was to assess the comparative efficacy of various types of denture adhesives in complete denture patients.

MATERIAL AND METHODS

A search was conducted for trials published in Scopus, PubMed, and Cochrane Central Register of Controlled Trials from inception until July 2023 (PROSPERO: CRD42023451045). A network meta-analysis was performed to assess the comparative efficacy of different denture adhesive types and ranked using the Surface Under the Cumulative Ranking (SUCRA) system. The Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) approach was used to assess the level of certainty of evidence.

RESULTS

Seventeen articles were included in the quantitative analysis. Cream denture adhesives significantly increased bite force in both incisal region (RR = 7.63[95%CI: 3.34, 11.91]) (P < .05) as well as premolar and molar regions (RR = 33.66[95%CI: 15.15, 52.16]). Cream adhesives significantly improved retention of dentures as assessed by the reduced number of denture dislodgments (RR = -5.35[95%CI: -9.93, -0.77]) (P = 0.022), Kapur's index of retention (maxillary denture) (RR = 0.80[95%CI: 0.18, 1.42]) (P = 0.012) and Kapur's index of retention (mandibular denture) (RR = 1.27[95%CI: 0.67, 1.87]) (P < .05). Powder adhesives significantly increased premolar and molar bite force (RR = 36.00[95%CI: 16.20, 55.79]) (P < .05) and Kapur's index of retention (mandibular denture) (RR = 1.54[95%CI: 0.58, 2.49]) (P = 0.002). None of the adhesives were statistically significant for remaining outcomes.

CONCLUSIONS

Cream and powder denture adhesives are effective in enhancing the retention of mandibular dentures (Kapur's index) and bite force in the premolar/molar region in complete denture wearers (moderate level of certainty of evidence).

CLINICAL RELEVANCE

Cream and powder denture adhesives are effective in improving the retention and function of complete dentures.

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.

The Effect of Herbal Denture Adhesive on Patient Satisfaction in Comparison to Traditional Type

Background The aim of this study was to compare the responses of 30 denture wearers' opinions concerning the efficiency of two types of adhesives and estimate their satisfaction level using denture adhesive (DA). Materials and methods 30 completely edentulous patients were divided randomly into two groups. Each group received one type of DAs (SECURE, COREGA) and was instructed to follow the same sequence of application. Each type of adhesive was used for seven days, as recommended by the manufacturer. The patients were requested to fill out a questionnaire considering their opinion and satisfaction regarding denture retention, chewing ability and duration of adhesives. Results The majority of patients stated that the prosthetic DAs enhanced their retention, chewing, stability, and efficiency of dentures. There was a significant difference in patient satisfaction regarding denture retention in the mandible and the duration of the adhesive in the mouth. Concerning ability of the patient to remove the adhesive from their mouth, the taste, or the retention of the maxillary denture, there were no statistically significant differences between the two DAs. Conclusions The results of the present study showed that overall satisfaction of complete denture wearers was high significantly different when a herbal DA was applied. This includes improvements in their duration of retention effectiveness, greater stability, and retention of the lower mandibular dentures. To use DA effectively, patients should be oriented by their dentists. Patient education is essential to provide them with a better understanding of both the appropriate technique for applying DA and the possible outcome they may experience.

A systematic review and meta-analysis to evaluate the efficacy of denture adhesives

OBJECTIVES

This systematic review aims to investigate the efficacy of denture adhesives (DAs) for complete dentures (CDs), and to provide clinical recommendations for prosthodontists and general practitioners.

DATA/SOURCES

Electronic databases (Medline, Embase, CENTRAL) and gray literatures were searched (up to March 2020) for relevant randomized and non-randomized controlled clinical trials (RCTs and CCTs) evaluating the efficacy of DAs when applied to CDs. Primary outcomes were objectively assessed variables directly related to mastication (denture retention, maximum bite force and masticatory efficiency). Secondary outcomes included other objectively assessed variables and patient-reported outcomes.

STUDY SELECTION

Of the 1729 records identified, 39 studies (43 articles) were included in the analysis. Among them, 23 were RCTs and 16 were CCTs, with two multicenter clinical trials (1 RCT and 1 CCT). Meta-analysis results indicated that DAs provided significantly higher retention (SMD 1.34, 95 % CI: 0.89-1.79, P < 0.001) for CDs. Bite force (SMD 0.98, 95 % CI: 0.50-1.47, P < 0.001) and masticatory performance (SMD 0.72, 95 % CI: 0.23-1.22, P = 0.004) of the CD wearers were also improved after using DAs, but the effect size was relatively smaller.

CONCLUSION

Based on the results of this systematic review, it is concluded that DAs can improve denture retention, bite force and masticatory performance of CD wearers.

CLINICAL SIGNIFICANCE

This study investigated the effects of all types of DAs for CDs in terms of their effects on denture retention, masticatory performance, oral health-related quality of life and oral microorganisms for CD wearers.

Masticatory performance of denture wearers with the use of denture adhesives: A systematic review

STATEMENT OF PROBLEM

Denture adhesives are products used by wearers of removable dental prosthesis; however, systematic reviews on their influence on masticatory performance are lacking.

PURPOSE

The purpose of this systematic review was to evaluate the efficiency of denture adhesives in improving the masticatory performance of users of complete dentures (CD).

MATERIAL AND METHODS

This systematic review was organized from the Preferred Reporting Items for Systematic Reviews and Meta-Analyses checklist, and the methods were registered on the international prospective register of systematic reviews (PROSPERO-CRD42020187385). The focus question was as follows: "Does the use of denture adhesives improve the masticatory performance of patients with removable dental prostheses?" The databases PubMed/MEDLINE, Scopus, Web of Science, and Cochrane Library were used to extract information.

RESULTS

The search yielded 1338 articles, of which 6 met the inclusion criteria and were selected. All included studies were crossover randomized controlled trials including bimaxillary edentulous individuals. Masticatory performance was evaluated by using a comminution and sieve method.

CONCLUSIONS

Denture adhesives significantly increased the masticatory performance of CD users.

Subjective Evaluation of Denture Adhesives: A Multicenter Randomized Controlled Trial

INTRODUCTION

Many reports show that denture adhesives improve the retention and stability of dentures. However, few randomized controlled trials have examined the effects of denture adhesives.

OBJECTIVE

This 10-center randomized controlled trial with parallel groups involving 200 edentulous patients wearing complete dentures aimed to evaluate the effects of short-term use of cream and powder denture adhesives.

METHODS

Patients were allocated into 2 cream- and powder-type adhesive groups and 1 control group. Intervention groups were treated with the 2 adhesives (1 each), and the control group received saline solution. Adhesive or control was applied to the denture-mucosal surface for 4 d, and data at baseline and after day 4 of intervention (i.e., 8 meals) were obtained. Patient satisfaction was evaluated with a 100-mm visual analog scale. Oral health-related quality of life was measured with the Japanese version of the Oral Health Impact Profile for Edentulous Patients. Perceived chewing ability was evaluated by a questionnaire regarding ease of chewing and swallowing food. Between-group comparisons were performed with Kruskal-Wallis tests with the Mann-Whitney U test adjusted by Bonferroni correction. Within-group comparisons of pre- and postintervention measurements were performed with the Wilcoxon signed-rank test. Intention-to-treat analysis was also performed.

RESULTS

Between-group comparisons showed no significant differences for general satisfaction or Oral Health Impact Profile for Edentulous Patients. However, significant differences in satisfaction with various denture functions with cream- and powder-type adhesives were seen in pre- and postintervention comparisons (P < 0.05). Significant differences were also observed for perceived chewing ability of hard foods (P < 0.05).

CONCLUSION

These results suggest that although denture adhesives do not invariably improve denture function, they do affect subjective evaluations and possibly chewing of hard foods. Therefore, the effects of denture adhesive use are insufficient to resolve any fundamental dissatisfaction with dentures ( ClinicalTrials.gov NCT01712802 ).

KNOWLEDGE TRANSFER STATEMENT

The results of this study suggest that denture adhesives should be applied under certain conditions; however, an appropriate diagnosis is important before application. These practice-based data provide information to establish evidence-based guidelines for applying denture adhesives.

Effect of Denture Adhesives in New Complete Dentures During a Function

Background:

Denture adhesives are often a matter of controversy. Patients seem to easily accept the use of denture adhesives, while professionals are more hesitant.

Objective:

The purpose of this study was to evaluate the self-perception, bite force and masticatory efficiency of complete denture wearers with denture adhesives.

Methods:

Fifteen complete denture wearers had their bite force measured by a gnathodynamometer in the molar region. Subjects also masticated 12 tablets of a chewable artificial test material for 35 masticatory cycles. The test material was washed, dried, sieved and weighed. Both tests were taken with and without the denture adhesive (Corega Ultra). The questionnaire Geriatric Oral Health Assessment Index (GOHAI) was applied to evaluate self-perception with dentures.

Results and Conclusion:

Masticatory efficiency and bite force for the control group (without denture adhesive) and for the group with denture adhesive presented no statistically significant differences (p= 0.2080 andp= 0.2489, respectively). Self-perception according to the GOHAI index was great for 13% of participants, 40% considered it regular and 47% evaluated it as bad. Within the limitations of this study, it can be concluded that the use of denture adhesive did not promote an improvement in bite force and masticatory efficiency. According to the GOHAI index, self-perception of the participants was classified as bad.

Choosing the best image processing method for masticatory performance assessment when using two-coloured specimens

Objective masticatory performance assessment using two-coloured specimens relies on image processing techniques; however, just a few approaches have been tested and no comparative studies are reported. The aim of this study was to present a selection procedure of the optimal image analysis method for masticatory performance assessment with a given two-coloured chewing gum. Dentate participants (n = 250; 25 ± 6·3 years) chewed red-white chewing gums for 3, 6, 9, 12, 15, 18, 21 and 25 cycles (2000 samples). Digitalised images of retrieved specimens were analysed using 122 image processing methods (IPMs) based on feature extraction algorithms (pixel values and histogram analysis). All IPMs were tested following the criteria of: normality of measurements (Kolmogorov-Smirnov), ability to detect differences among mixing states (anova corrected with post hoc Bonferroni) and moderate-to-high correlation with the number of cycles (Spearman's Rho). The optimal IPM was chosen using multiple criteria decision analysis (MCDA). Measurements provided by all IPMs proved to be normally distributed (P < 0·05), 116 proved sensible to mixing states (P < 0·05), and 35 showed moderate-to-high correlation with the number of cycles (|ρ| > 0·5; P < 0·05). The variance of the histogram of the Hue showed the highest correlation with the number of cycles (ρ = 0·792; P < 0·0001) and the highest MCDA score (optimal). The proposed procedure proved to be reliable and able to select the optimal approach among multiple IPMs. This experiment may be reproduced to identify the optimal approach for each case of locally available test foods.

Knowledge, attitude and practices of denture adhesives use among private dental practitioners' of jabalpur city, madhya pradesh: a cross sectional survey

The use of denture adhesives (DA) and their role in prosthodontics has been a conflicted topic both in clinical practice and dental education. The use of adhesives, are viewed as poor reflection of their clinical skills and prosthetic expertise or to provide retention to an ill-fitting prosthesis by many dentists. These conflicting views have raised many doubts among practicising dentists on the use of DAs in their clinical practice. The aim of this study was to assess the knowledge, attitudes and practices of DA use among private dental practitioners' of Jabalpur city, Madhya Pradesh. This descriptive, cross-sectional survey was conducted using a self-administered questionnaire involving private dental practitioners of Jabalpur city. A total of 172 private dental practitioners of Jabalpur made up the sample of the study. A comprehensive, closed-ended, self-administered questionnaire was employed which was designed to collect the sociodemographic details and to assess the knowledge, attitudes and practices of DA use among private dental practitioners'. The institutional review committee approved the study. Data were imported to the SPSS 13.01 program to draw the means and percentages. Majority of the dentists were males (55 %), preponderance (68 %) of the dentists were in the 21-30 years age-group. Greater part of the study population comprised of general dental practitioners (GDPs) (81 %). When the subjects were questioned if DA were soluble in saliva, 32 % of the GDPs replied wrongly. Similarly 25 % of the GDPs didn't know that using DA with incompletely removed old DA affected tissue health. Zinc containing DA are recently held responsible for causing neurological diseases on their prolonged usage, 71 % of the GDPs and 74 % of other specialists were unaware in this context. A total of 115 (83 %) GDPs, 6 (100 %) prosthodontists and 22 (81 %) other specialist's used DA as a beneficial adjunct in their clinical practice. DA being used frequently by the dentists, unfortunately they did not have sufficient knowledge regarding the material. The attitude is a reflection of an individual's knowledge, which was also not homogeneous. By pursuing continuing education courses, the practitioners can update themselves regarding new technology and materials, thus improving the standard of care for prosthodontic patients.

Viscosity and adhesion strength of cream-type denture adhesives and mouth moisturizers

We evaluated adhesion strength to acrylic resins under various experimental conditions and viscosity of 4 cream-type denture adhesives and 2 mouth moisturizers. The viscosity was determined by a sine-wave vibro viscometer. The adhesion strength tests were performed with 2 resin plates at a universal tester. In Method A, various constant thicknesses of material layer were tested and tensile strength was measured, while in Method B a constant load was applied before measurement. Five tests were carried out for each measurement. With Method A, adhesion strength increased exponentially as the layer got thin. Effect of the material thicknesses (contribution ratio ρ=79.0%) was much larger than that of material type (ρ=15.3%). Materials with higher viscosity had greater levels of adhesion strength in Method A, whereas those with the higher viscosity had lower levels of adhesion strength in Method B. Adhesion strength was significantly affected by the experimental condition prior to applying tension.

Effect of denture adhesive on the micro-organisms in vivo

BACKGROUND

 Denture adhesives increase the retention and stability of dentures in edentulous patients, especially in cases where salivary flow is impaired or in the management of traumatised oral mucosa.

OBJECTIVES

The effect of a denture adhesive on the oral flora at different time intervals.

METHOD

Thirty denture-wearing patients were involved in this study. While half of the group received a denture adhesive, the other half did not. At baseline, 1 and 2 months after delivering the dentures, smear samples were obtained from the saliva, palate and the dentures. Candida albicans, Candida krusei, Candida glabrata, Candida spp., Staphylococcus aureus, Moraxella catarrhalis, α-haemolytic streptococci, β-haemolytic streptococci, Pneumococcus aureus, S. anginosus, S. intermedius, S. constellatus, S. sanguis, S. gordonii, S. mitis, S. mutans, S. salivarius, and yeasts were investigated. The data were statistically analysed using anova and repeated measures.

RESULTS

Most types of the micro-organisms were not seen and could not be analysed statistically except α-haemolytic streptococci and C. albicans. No statistically significant difference was found for α-haemolytic streptococci and C. albicans in saliva, palate and the denture at all time intervals.

CONCLUSIONS

Prolonged use of the denture adhesive tested up to 2 months did not yield to increase in micro-organisms of the oral flora.

Clinical evaluation of three denture cushion adhesives by complete denture wearers

OBJECTIVE

The aim of this study was the clinical evaluation of three denture cushion adhesives and whether the results were correlated to Kapur Index for denture-supporting tissues.

BACKGROUND

Various types of denture adhesives are used among denture patients. However, information on the clinical behaviour of denture cushions is limited.

MATERIALS AND METHODS

Thirty edentulous patients had their denture-supporting tissues scored by Kapur Index and their old dentures replaced. They received three brands of denture cushion adhesives (Fittydent(®) , Protefix(®) and Seabond(®)) and were instructed to use them in a sequence according to the group they were randomly assigned to. Each brand of adhesive was used for 48 h on the lower denture according to the manufacturer's suggestions. After each brand was used, participants spent 24 h without applying any sort of adhesive. Finally, a questionnaire evaluating and comparing the performance of each brand was filled out.

RESULTS

Denture adhesives generally improved patient satisfaction and masticatory ability, especially in participants with poor Kapur Index and those who reported a poor retention of their old dentures.

CONCLUSION

Fittydent(®) was the most preferred adhesive, showing the best retention and the longest duration of its effect, but also reported as difficult to remove from the denture-bearing area.

An international multicenter study on the effectiveness of a denture adhesive in maxillary dentures using disposable gnathometers

No consensus has been achieved on whether denture adhesives are beneficial adjuncts in denture-wearers management. The purpose of this international multicenter study was to determine objectively the effect of a denture adhesive (Kukident) on the retention of complete maxillary dentures using disposable gnathometers. The disposable gnathometers have a decimal scale for measuring the incisal force before dislodgement (= maximum incisal force) of maxillary dentures. The intra-observer reliability, the inter-observer reliability, and the linearity of the gnathometer units of the disposable gnathometers were examined in three pilot studies. Participants of the international multicentre main study were 88 patients who had been selected for complete maxillary denture treatment. The maximum incisal force of their previous and new denture without and with adhesive was measured using disposable gnathometers. The intra- and inter-observer reliability of the disposable gnathometers was very good, and there was a linear relation between the gnathometer units. The effect of the denture adhesive on the maximum incisal force of complete maxillary dentures was statistically significant in previous as well as new dentures, being more pronounced in previous than in new dentures.

Subjective Assessment by Patients of the Efficiency of Two Denture Adhesive Pastes

PURPOSE

This study evaluated the subjective responses of 30 denture wearers with regard to the effectiveness of two denture adhesive pastes.

MATERIALS AND METHODS

Thirty patients responded to questions related to retention, chewing ability, taste, duration of adhesives in the mouth, and removal; comparing the use of two denture adhesives based on polymethylvinylether-maleic anhydride compounds or carboxymethyl cellulose.

RESULTS

The denture adhesive paste based on polymethylvinylether-maleic anhydride (PVM-MA) compound was rated higher (73% and 87%) than carboxymethyl cellulose (CC) adhesive paste (60% and 37%) on chewing ability and duration in the mouth (p= 0.0001 and p= 0.0001, respectively) by experienced denture wearers in both maxilla and mandible. There were no statistically significant differences between the two denture adhesive pastes on the retention of maxillary dentures, taste, and removal of the adhesive (p= 0.08, p= 0.67, and p= 0.41, respectively).

CONCLUSIONS

All subjects responded that the retention of their dentures was either a little better or much better when using either of the adhesive pastes.

Professional attitudes toward denture adhesives: A Delphi technique survey of academic prosthodontists

STATEMENT OF PROBLEM

The use of denture adhesives and their role in prosthodontics has been an intriguing and conflicted topic, both in clinical practice and dental education.

PURPOSE

This study generated discussion, and if possible, obtained a consensus on a series of issues related to denture adhesives among a group of leading academic prosthodontists.

MATERIAL AND METHODS

The Delphi Technique survey method was used. It consists of a series of survey questionnaire rounds to a panel of experts to either develop a consensus (>70% agreement) or to clarify the reasons for multiple schools of thought on a topic. A 24-item Delphi questionnaire was sent to an expert panel that consisted of a 33% regionally stratified random sample of program directors of undergraduate complete denture courses in US dental schools. The 5 major topic areas on denture adhesives addressed by the questionnaire items were (1) general perceptions, (2) specific clinical uses/misuses, (3) patient education, (4) inclusion in dental curricula, and (5) overall opinions of utility.

RESULTS

Of the 18 randomly selected panelists, 94% (n = 17) agreed to participate, with either 16 or 17 fully participating in each of the 3 survey rounds. The panel achieved consensus and clearly concluded that denture adhesives: (1) are a useful adjunct in denture prosthesis services, having specific roles in both the fabrication and postinsertion phases; (2) had the potential for misuse, both by dentists and by patients; and (3) should be an integral part of patient education for all denture patients and of the undergraduate dental curriculum. However, the panel was unable to achieve consensus on whether denture adhesives should be used at the postinsertion phase for immediate denture patients and whether, on the whole, they were a beneficial adjunct in denture patient management (59% agreed they were). The panelists also clearly expressed their concerns that neither dentists nor patients should use denture adhesives as a substitute for either good clinical practices or proper denture maintenance routines.

CONCLUSIONS

This panel of leading academic prosthodontists concluded that denture adhesives are a useful adjunct in denture prosthesis services, with specific roles in both fabrication and postinsertion phases. They also indicated that only through education, for dentists and patients, would the dual goals of maximizing the beneficial aspects of denture adhesive use while minimizing the misuse of denture adhesives be achieved.

Some clinical investigations on retention forces of maxillary complete dentures with the use of denture fixatives

The aim of this study was to evaluate objectively and clinically the relative improvement in retention forces of complete dentures with the use of three proprietary denture fixatives. Using the UCL Retentiometer, retention forces of ill-fitting maxillary complete dentures were measured with saliva alone as the interface medium and with the use of the three test denture fixatives in edentulous subjects over a period of 6 h. Results showed that forces with saliva alone were consistently and significantly lower when compared with the forces measured at any test period with the use of the test fixatives. A sixfold improvement in forces from the salivary baseline values was observed when these materials were used. However, the test fixatives showed substantial variations in retention forces depending on the physical formulation of the material. Whilst the powder variety was effective immediately after its application, retention forces with the liquid and paste materials did not peak until 3 h post-insertion. Measurements at 6 h post-insertion stage showed that the powder fixative was the least effective of the three materials. This was mainly attributed to the rapid washing of the active ingredients by saliva because of the absence of oily base present in the paste and liquid materials.

Denture adhesives--pH and buffering capacity

Aqueous solutions of some denture adhesives will produce a pH below the critical pH of hydroxyapatite. This article measured the pH of selected denture adhesives. The pH and buffering capacity were established for 10 readily available denture adhesives. The pH was determined from samples in dilutions of 1:10, 1:20, 1:30, and 1:40 denture adhesive to deionized water. A glass pH electrode coupled to a pH meter was used for pH determination. Six of the 10 denture adhesives tested had pH values below the critical pH of hydroxyapatite. This pH was maintained for the 2-hour duration of the testing. Prolonged contact of denture adhesive and tooth substances may dissolve hydroxyapatite crystals. Samples of denture adhesives to determine buffering capacity were prepared in a ratio of 1:20 by weight of denture adhesive to deionized water. Another series of samples was prepared in a ratio of 1:20 by weight of adhesive to freshly cannulated submandibular saliva. The pH was determined at the 24-hour time interval. Samples were then titrated with 0.1N sodium hydroxide solution in the presence of phenolphthalein. The same denture adhesives demonstrated low pH values at the 2-hour and 24-hour time intervals. These samples tended to be well buffered. It is recommended that denture adhesives with low pH values not be used in an environment with natural teeth or remnants of natural teeth.

The use of denture adhesives as an aid to denture treatment

Denture adhesives are used by more than five million denture wearers in the United States. All dentists strive to achieve stable, retentive, and comfortable dentures that do not require the use of denture adhesives. However, dentists may prescribe and use denture adhesives as a legitimate therapeutic and effective procedure in denture treatment and in denture aftercare, when indicated. Denture patients should use denture adhesive on the advice of their dentists and should be instructed in its proper use and cautioned against misuse.

Effect of a denture adhesive on complete denture dislodgement during mastication

A method of evaluating the denture stabilizing effects of a denture adhesive by means of counting denture dislodgements during the eating of a standardized portion of a test food is described. A reduction in the number of such dislodgements after application of a denture adhesive, as compared to eating the same food without adhesive applied to the denture, was used as a measure of adhesive effectiveness. Subject responses to a number of denture-performance satisfaction parameters were also obtained. With a test adhesive, significant reductions in dislodgement were found using steak, taffy-apple, a hard-roll sandwich, and celery as test foods among 16 subjects with dentures that fit well. Analysis of subjective evaluations indicated that the test adhesive was perceived as having effected: (1) improved chewing ability, (2) reduced denture wobble, (3) improved confidence, (4) increased comfort, and (5) reduced amount of food particles collecting under the denture, all to a significant degree (p < .01). It is suggested that additional data from controlled clinical studies are needed to allow proper assessment of the usefulness and possible abuse effects of denture adhesive products. This method, and the resulting data, are offered as a stimulus to the end.