Clinical outcomes and costs of conventional and digital complete dentures in a university clinic: A retrospective study.

STATEMENT OF PROBLEM: Scientific data analyzing the clinical outcomes and costs of complete dentures fabricated by using conventional and computer-aided design and computer-aided manufacturing (CAD-CAM) processes are lacking. PURPOSE: The purpose of this retrospective study was to compare the treatment duration, financial costs, and postdelivery adjustments of CAD-CAM and conventional removable complete dentures. MATERIAL AND METHODS: Thirty-two edentulous participants (16 women, 16 men; age 35-85 years) who had received either CAD-CAM (n=16) or conventional (n=16) maxillary and mandibular removable complete dentures provided by prosthodontists with a minimum of 2 years of experience were evaluated. The CAD-CAM denture systems were either DDS-AV (AvaDent Digital Dental Solutions) (n=11) or DD-IV (Wieland Digital Denture) (n=5). The total treatment period (days) was recorded at 3 different time points (T0: preliminary alginate impression; T1: denture delivery; T2: last scheduled postdelivery adjustment). Adjustments during the follow-up (after T2) were noted and included the removal of areas of excessive pressure, relining, or repairs. The costs of the dental treatment and the laboratory fees were calculated. The Wilcoxon rank sum tests were used for statistical analysis (α=.05). RESULTS: No statistically significant difference regarding the treatment duration between digitally and conventionally fabricated removable complete dentures was found: T0-T1 (P=.889); T1-T2 (P=.675); T2- T3 (P=.978). No significant difference was found in the number adjustments for areas of excessive pressure, relines, or repairs (P=.757, P=1.000, P=1.000) during the period. Laboratory costs of CAD-CAM removable complete dentures were significantly lower than those of conventional removable complete dentures (P<.001), but clinical fees were similar between groups (P=.596), resulting in a reduction in the overall total costs for the CAD-CAM removable complete dentures (P=.011). Regarding the number of clinical visits, neither the group (conventional/CAD-CAM (P=.945)/DDS-AV/DD-IV [P=.848]) nor the interaction group (conventional/CAD-CAM and DDS-AV/DD-IV)/period (P=.084/P=.171) showed any significant differences. CONCLUSIONS: CAD-CAM removable complete dentures can be considered a viable alternative to conventional removable complete dentures regarding treatment duration, clinical and follow-up visits, adjustments, and maintenance requirements.

Oral diadochokinesis and associated oro-facial function in young and old German mother-tongue speakers: A cross-sectional study.

OBJECTIVES: The aims of this study were to compare oral diadochokinesis and to test associations with oro-facial functional parameters in healthy young and old German speakers. BACKGROUND: Oral diadochokinesis is a key component in the concept of oro-facial hypofunction and relates to tongue and lip motor function but may depend on the linguistic background. MATERIALS AND METHODS: Healthy German speakers with a minimum of 20 teeth were recruited to form a young (<60 years) and an older group (≥60 years). Oral diadochokinesis was assessed as the number of repetitions/s for the monosyllables /pa/, /ta/ and /ka/ to evaluate movement capacity of the lip, the anterior region of the tongue and the posterior region of the tongue, respectively. Maximum voluntary lip force, maximum voluntary bite force, masticatory performance, maximum voluntary tongue pressure, xerostomia and swallowing function were assessed with validated instruments. Results are presented as median (IQR). RESULTS: Sixty participants formed the younger group (n = 35, 30.0 years [24.0-49.0]) and the older group (n = 25, 64.0 years [62.0-72.0]). Counts/s of /ta/ were different between age groups (younger group: 6.0 vs older group: 5.4) but not for syllables /pa/ (younger group: 6.0 vs older group: 5.8) and /ka/ (younger group: 5.6 vs older group: 5.0). The oral diadochokinesis with /pa/ was overall associated with maximum voluntary lip force; oral diadochokinesis performed with /ta/ was associated with tongue pressure, and oral diadochokinesis with /ka/ with swallowing function. Masticatory performance was not associated with oral diadochokinesis but with maximum voluntary bite force, xerostomia and with maximum voluntary tongue pressure. CONCLUSIONS: The published thresholds for oral diadochokinesis should be reconsidered in non-Japanese mother-tongue speakers. However, they still play an important role in the overall concept of oro-facial functional assessment.

Validation of a novel diagnostic tool for decreased tongue pressure.

INTRODUCTION: Reduced tongue pressure may render eating and swallowing difficult. The purpose of this study was to investigate whether the tongue training device can also be used as a diagnostic device and whether its sensitivity and specificity are equal to the numerical tongue pressure measuring device. MATERIAL AND METHODS: The target group is patients aged 70 years and over who are hospitalised for rehabilitation. Tongue pressure was measured by both, a tongue pressure measuring instrument and a tongue training tool. The diagnosis of the reduced tongue pressure was made with the tongue pressure measuring instrument and set the verified with the novel tongue training tool. RESULTS: Sixty-two participants were included in the study. Forty-five were classified by the tongue pressure measuring device and 53 by the tongue training device as 'low tongue pressure'. Spearman correlation confirmed a positive correlation between the tongue pressure measuring device and the tongue training device rs  = 0.800, p = 0.01 level (2-tailed). The tongue training device test identified sensitivity was 100%, and its specificity was 52.9%. The AUC of the ROC curve is 0.901. CONCLUSION: The tongue training device seems a simple, safe and readily available alternative to the tongue pressure measuring device for the diagnosis of low tongue pressure, with an excellent sensitivity and very good specificity.

In vitro Activity of Oral Health Care Products on Candida Biofilm Formation.

The activity of mouthwash ingredients used in daily oral care (chlorhexidine digluconate, benzalkonium chloride, povidone iodine solution, tea tree oil) and of nystatin was evaluated not only on planktonic Candida albicans or C. glabrata, but also on the inhibition of biofilm formation. A microbroth dilution technique was used to determine the minimum inhibitory concentration of the substances against two laboratory strains and seven clinical isolates. Furthermore, a potential inhibition of biofilm formation of C. albicans or C. glabrata (single-species biofilm or mixed with two oral bacteria) was assessed. The results showed an activity of all tested substances against all C. albicans and C. glabratastrains. In the biofilm assays, a concentration-dependent effect of the substances was visible. However, a low concentration of povidone iodine solution and in particular of benzalkonium chloride seemed to increase the virulence of C. albicans. Most test substances affected both bacteria and yeasts in the mixed biofilms, only nystatin predominately reduced the yeasts. In conclusion, nystatin might be the drug of choice when exclusively preventing the colonization of Candida sp. in biofilms. The alternatives, benzalkonium chloride, povidone iodine solution, and tea tree oil, should be investigated further.

Variability in tongue pressure among elderly and young healthy cohorts: A systematic review and meta-analysis.

OBJECTIVES: Tongue pressure (TP) is used for the diagnosis of oral hypofunction; however, the impact of several variables on TP is unclear. Therefore, the current systematic review and meta-analysis aimed to analyse the variability in tongue pressure among healthy individuals aged ≥60 years vs <60 years. Secondary outcomes were the influence of gender and the type of measuring device (Iowa Oral Performance Instrument (IOPI) vs JMS tongue pressure measurement device (JMS)). METHODS: PubMed and the Japanese database Ichushi-Web were searched systematically by two independent reviewers for studies reporting TP values in healthy populations. Clinical studies published between 1959 and June 2020 with more than 10 participants, written in English, German or Japanese, were included. A random-effects meta-regression for aggregate-level data was applied (α < 0.05). RESULTS: Sixty-eight studies reported TP for a total of 13 773 subjects aged <60 years (n = 3265) and ≥60 years (n = 10 508). TP was significantly higher in subjects <60 years (estimated weighted mean (EWM) ± standard error = 51.9 ± 1.28 kPa; 95% CI = 49.4-54.4) relative to those ≥60 (EWM = 34.7 ± 0.94 kPa; 95% CI = 32.8-36.5) (P < .001), men (EWM = 45.9 ± 2.09 kPa; 95% CI = 41.8-50.0) relative to women (EWM = 39.3 ± 1.68 kPa; 95% CI = 36.0-42.6) (P = .015) and when assessed with the IOPI (EWM = 51.9 ± 1.32 kPa; 95% CI = 49.3-54.5) compared to the JMS (EWM = 33.5 ± 0.63 kPa; 95% CI = 32.2-34.7) (P < .001). In terms of gender, there was no significant difference in TP among subjects ≥60 years (P = .282). However, in subjects younger than 60, a significant difference was observed (P = .004). CONCLUSIONS: Healthy populations aged <60 years showed significantly higher TP than those aged ≥60 years. TP values ascertained by the IOPI are significantly higher than those obtained with the JMS.

Reliability and comparability of methods for assessing oral function: Chewing, tongue pressure and lip force.

BACKGROUND: Quantitative clinical assessment tests for oral function have become popular in patient assessment; however, their comparability remains unclear. OBJECTIVE: To assess the reliability and comparability of pairs of different instruments for measuring maximum tongue pressure (MTP), chewing function (CF) and maximum lip force (MLF), and to analyse the influence of subjects' characteristics on the applied instruments. METHODS: Each pair of instruments, as well as a single device measuring the maximum voluntary bite force (MBF), was assessed across 26 healthy volunteers. The respective pairs of devices were compared using Bland-Altman plots and linear regression analysis. Furthermore, the influence of age, occlusal support zones, number of functional occlusal units, MBF, MTP and MLF were investigated as predictors on CF using a generalised estimating equation model. RESULTS: Neither the two assessments of CF, nor of MLF were correlated to each other, but there was a significant correlation between the assessments of MTP. Hue-Check Gum was able to demonstrate a significantly higher CF in younger compared to older individuals (P = .004) and individuals with high numbers compared to low numbers of occlusal units (P < .001). Those differences could not be demonstrated with the Vivident chewing gum. CONCLUSION: The absolute values of MTP assessed by the two applied devices cannot directly be compared, although normalised values may be directly comparable. Moreover, our observations suggest that the Hue-Check Gum was able to discriminate the effects of age and the number of occlusal units on CF. Our observations suggest that the two gums cannot be used interchangeably.