A German version of the Oral Impacts of Daily Performances-reliability and validity.

OBJECTIVE: The Oral Impact of Daily Performances (OIDP) is a dental patient-reported outcome measure (dPROM) for the estimation of oral health-related quality of life (OHRQoL) and takes the frequency as well as the severity of problems into account; however, it is not available in German language. The aim of this study was, therefore, to evaluate the reliability and validity of the German version of the OIDP in patients of a private practice. MATERIAL AND METHODS: Translation of the original OIDP version was performed by a forward-backward process. Reliability was evaluated in terms of construct stability (test-retest) for the single items and the sum scores. The responsiveness to change in oral health status was assessed by pre- and post-treatment comparison, in addition. Validity was assessed as convergent validity in comparison with other dPROMs (OHIP-14; GOHAI) and objective dental findings. RESULTS: A total of 330 patients participated in this study (mean age: 42.0 (18.0)). The OHRQoL of the participants was relatively high (OIDP score 4.3 (SD 14.3), OHIP score 4.8 (SD 5.3), GOHAI score 54.2 (SD 5.4)). A moderate construct stability for the total OIDP-score (ICC 0.686) was found whilst reliability for the single items varied between 0.179 (social contact) to 0.559 (showing teeth). Significant correlations were found for OIDP and OHIP (p < 0.001; r = 0.361) and OIDP and GOHAI (p < 0.001; r = - 0.391) indicating moderate validity with a tendency to even stronger correlations for OIDP-s and OIDP-f (r ≥ 0.500). CONCLUSIONS: The German version of the OIDP demonstrated sufficient reliability and validity. OIDP's general performance should be interpreted cautiously as the outcome was detected in a specifically healthy population. CLINICAL RELEVANCE: The OIDP is yet the only dPROM that evaluates both severity as well as frequency which makes validation interesting regarding specific target populations.

Accuracy of polyether and vinylpolysiloxane impressions when using different types of 3D-printed impression trays - an in vitro study.

OBJECTIVES: To investigate dimensional accuracy of polyether (PE) and vinylpolysiloxane (VPS) impressions taken with manually fabricated and 3D-printed trays. MATERIALS AND METHODS: To evaluate impression accuracy, highly precise digital data of a metallic lower jaw model with prepared teeth (regions 34 and 36), an implant (region 47) and three precision balls placed occlusally along the dental arch served as reference. PE (Impregum, 3M Oral Care) and VPS (Aquasil, Dentsply Sirona) impressions (n = 10/group) were taken with trays fabricated using different materials and manufacturing techniques (FDM: filament deposition modeling, material: Arfona Tray, Arfona; printer: Pro2, Raise3D; DLP: digital light processing, material: V-Print Tray, VOCO, printer: Max, Asiga; MPR: manual processing with light-curing plates, material: LC Tray, Müller-Omicron) including an open implant impression. Scans of resulting stone models were compared with the reference situation. Global distance and angular deviations as well as local trueness and precision for abutment teeth and scan abutment were computed. Possible statistical effects were analyzed using ANOVA. RESULTS: Clinically acceptable global accuracy was found (all mean absolute distance changes < 100 µm) and local accuracy for single abutments was excellent. All factors (abutment type, impression material, tray material) affected global accuracy (p < 0.05). In particular with PE impressions, MPR trays led to the best accuracies, both in horizontal and vertical direction. CONCLUSIONS: Within the limitations of this in vitro study, impression accuracy was high in use of both polyether and vinylpolysiloxane combined with different 3D-printed and customized trays making them recommendable for at least impressions for smaller fixed dental prostheses. Manually fabricated trays were overall still the best choice if utmost precision is required. CLINICAL RELEVANCE: Based on the results of this study, use of innovative CAD-CAM fabrication of individual impression trays fulfills the perquisites to be a viable option for impression making. In the sense of translational research, performance should be proved in a clinical setting.

Very old age impacts masticatory performance: a study among sexagenarians to centenarians.

OBJECTIVE: This cross-sectional pilot study evaluated the impact of age on masticatory performance among individuals aged 65 to 106 years, as part of the Heidelberg Dental Centenarian Study (HD-100Z) conducted in South-Western Germany. MATERIALS AND METHODS: A total of 31 centenarians were recruited, alongside 31 individuals each from the age groups 75-99 and 65-74, matched based on sex, prosthetic status, and number of teeth. Masticatory performance was assessed using a two-colored chewing gum test and digital image processing. Multiple linear regression analysis was performed to assess the effect of age, sex, number of teeth, type of prosthesis on the masticatory performance. RESULTS: Masticatory performance, as measured by the standard deviation of hue in the chewing gum test, decreased significantly in centenarians compared to individuals aged 75-99 years (-0.112, p = 0.037) and those aged 65-74 years (-0.274, p < 0.001). The effects of sex, number of teeth, and type of prosthesis on masticatory performance were not significant associations (p ≥ 0.135). CONCLUSION: The findings suggest that age may have a significant influence on masticatory performance in the studied age groups, challenging previous notions that aging itself has little impact on masticatory ability. The inclusion of centenarians in the study highlights the need for further investigation into masticatory function in age groups reaching up to 100 years or more. CLINICAL RELEVANCE: This study contributes to the understanding of how ageing affects oral function, which may guide dental treatment approaches for older individuals, and set the stage for more in-depth investigations in this field in the future.

Biaxial flexural strength of 3D-printed 3Y-TZP zirconia using a novel ceramic printer.

OBJECTIVES: To compare the strength and reliability of 3D-printed 3Y-TZP zirconia manufactured with various printing orientations and staining. MATERIALS AND METHODS: A total of one-hundred cylindrical zirconia specimens were designed and fabricated using 3D printing and processed according to ISO 6872 standards. Of these specimens, 80 were 3D printed using the new ZIPRO-D (ZD) 3D ceramic printer. In this ZD group, 60 specimens were printed in a vertical orientation and were either stained after debinding (ZD1, x-orientation, n = 20) or not stained (ZD2, x-orientation, n = 20; ZD3, y-orientation, n = 20) and the remaining 20 specimens out of n = 80 were printed in a horizontal orientation (ZD4). Further 20 specimens out of the entire sample N = 100 were printed vertically with the CeraFab7500 3D ceramic printer (LC). All completed specimens were loaded until fracture using a universal testing machine. Biaxial flexural strengths and Weibull parameters were computed for the ZD groups and for the LC group. Group and sub-group effects were evaluated using Welch ANOVA (alpha = 0.05). RESULTS: The mean (standard deviation, SD) biaxial flexural strengths of vertically oriented ZD samples with (ZD1) and without (ZD2/ZD3) staining were 811 (197) and 850 (152) MPa, respectively (p > 0.05). The ZD4 (horizontally printed), 1107 (144) MPa, and LC (1238 (327)) MPa samples had higher mean (SD) flexural strengths than the ZD1-3 specimens. No difference was observed between the ZD4 and LC group (p > 0.05). Weibull moduli were between m = 4.6 (ZD1) and 9.1 (ZD4) in the ZD group and m = 3.5 in the LC group. CONCLUSIONS: All tested 3D-printed zirconia specimens exceeded the flexural strengths required for class 5 restorations according to ISO 6872 standards. While the flexural strengths of zirconia printed using the novel ZD device in the vertical orientation are lower than those of zirconia printed using the LC printer, the ZD printer shows at least comparable reliability. CLINICAL RELEVANCE: 3D-printing of zirconia is a new technology in dental application. Based on the presented strengths values, clinical application of 3D-printed zirconia for fixed dental protheses can be recommended.

A new CAD/CAM tooth mobility simulating model for dental in vitro investigations.

OBJECTIVES: To validate a new tooth mobility simulating in vitro model for biomechanical tests of dental appliances and restorations. MATERIAL AND METHODS: Load-deflection curves for teeth in CAD/CAM models (n = 10/group, 6 teeth/model) of the anterior segment of a lower jaw with either low tooth mobility (LM) or high tooth mobility (HM) were recorded with a universal testing device and a Periotest device. All teeth were tested before and after different ageing protocols. Finally, vertical load capacity (Fmax) was tested in all teeth. RESULTS: At F = 100 N load, vertical/horizontal tooth deflections before ageing were 80 ± 10 µm/400 ± 40 µm for LM models and 130 ± 20 µm/610 ± 100 µm for HM models. Periotest values were 1.6 ± 1.4 for LM models and 5.5 ± 1.5 for HM models. These values were within the range of physiological tooth mobility. No visible damage occurred during ageing and simulated ageing had no significant effect on tooth mobility. Fmax values were 494 ± 67 N (LM) and 388 ± 95 N (HM). CONCLUSION: The model is practical, easy to manufacture and can reliably simulate tooth mobility. The model was also validated for long-term testing, so is suitable for investigating various dental appliances and restorations such as retainers, brackets, dental bridges or trauma splints. CLINICAL RELEVANCE: Using this in-vitro model for high standardised investigations of various dental appliances and restorations can protect patients from unnecessary burdens in trials and practice.

Prevalence of temporomandibular disorders and bruxism in seniors.

BACKGROUND: Information on the prevalence of temporomandibular disorders (TMD) or possible/probable bruxism in seniors is heterogeneous and sparse. OBJECTIVES: To elucidate the prevalence of TMD and possible/probable bruxism in German adults aged 60 years and older. METHODS: Participants of the Interdisciplinary Longitudinal Study of Adult Development and Aging (ILSE) born between 1950-1952 (C1) and 1930-1932 (C2) were examined in 2014-2016 (fourth wave). The participants were surveyed and clinically examined by one calibrated examiner. Two questions of the Patient Health Questionnaire (PHQ) were utilised to evaluate self-reported bruxism. The clinical examination included signs of probable bruxism and the RDC/TMD examination protocol. RESULTS: Data from 191 participants were available. No RDC/TMD diagnosis was made in 83.2%. Of the participants, 15.2% received a single diagnosis and 1.6% multiple diagnoses that included disc displacements (9.4%) and degenerative joint diseases (8.9%). A total of 24.7% reported bruxism that included self-reported awake bruxism in 11.9% and sleep bruxism in 16.2%. Wear was clinically identified in 27.2% of the participants. No sex-related differences were observed. Significant differences were detected for probable bruxism between C1 (14.1%) and C2 (54.3%). CONCLUSION: In the German population aged 60 years and older, the prevalence of TMD is 16.8%. TMD is characterised by temporomandibular joint disorders, including disc displacements and degenerative joint disorders. Bruxism was observed in a quarter of the old population.

Influence of geometric dimensions on early failures of adhesively retained composite resin core build-ups.

OBJECTIVE: To determine the influence of the geometric dimensions of core build-ups on early core build-up failure, that is, loss before definitive prosthesis cementation. MATERIALS AND METHODS: Adhesive core build-ups of exclusively vital teeth in 114 participants were evaluated (n materials: 40 Rebilda DC, 38 Multicore Flow, 36 Clearfil DC Core; n teeth: 8 incisors, 54 premolars, 52 molars). Impressions of the abutment teeth were made (1) after removal of insufficient restorations/caries and (2) after core build-up and preparation for a fixed prosthesis. Digitized model surfaces of both situations were aligned (Geomagic Design X) and core build-up volume (VCBU ), remaining hard tissue volume (VAbut ), and size of the adhesive surface (Aadh ) were assessed. The derived measure dCBU  = VCBU /Aadh can be interpreted as mean arithmetic core build-up thickness. Associations between participant or core build-up design characteristics and the occurrence of early failures were statistically evaluated (SPSS v27, α = 0.05). RESULTS: A total of six (5.3%) core build-up failures were registered. Higher participant age, greater core build-up volume VCBU and greater arithmetic uniform thickness dCBU were associated with a greater incidence of failure in bivariate and univariate, however, not in multivariate statistics. CONCLUSIONS: Core build-up volume and thickness were associated with early success or failure. CLINICAL SIGNIFICANCE: In the case of voluminous/thick core build-ups in relation to the adhesive surface, additional measures, such as the preparation of retentive elements to increase the bonding area, might be considered to reduce the risk of early core build-up failure.

Adapting the German version of the dental environment stress questionnaire.

AIMS: To develop a German version of the Dental Environment Stress (DES) questionnaire, and to evaluate its reliability and validity. METHODS: The original English DES questionnaire was translated into German using a forward-backward translation process. To evaluate construct stability, a subgroup of dental students (n = 43) completed the DES twice (interval: 1 week). To evaluate how the DES responds to anticipated changes in stress, all dental students' (n = 64) DES scores and saliva cortisol levels administered from a clinical study were compared between holiday and term time. Furthermore, the Depression, Anxiety and Stress Scale (DASS) and a stress self-assessment were used to determine the validity of the DES. Reliability analyses were calculated using Kendall's tau correlations. To estimate reliability strength, correlation coefficients and intraclass correlations (ICCs) were used. RESULTS: Regarding construct stability, 24 of 25 DES items had at least moderate correlations, and most items showed strong correlations. Correlations for the seven subdomains were good (range: 0.778-1.000). The same was true for the total DES score (ICC: 0.944). Correlations for response to term-time stress were weaker and more varied. Validity analyses revealed fair correlations between the DES and students' self-assessment (Pearson's r = .592) and DASS score (Pearson's r = .392), suggesting satisfactory validity. Stress levels were quite similar between baseline and follow-up. CONCLUSION: The German DES is a reliable tool for evaluating stress in dental students. Because it can be used to identify individual stressors in various categories, it might enable the detection of specific stress situations in educational situations and facilitate solutions (adjustment of curricula, tailored consulting services).

Orthodontic shear bond strength and ultimate load tests of CAD/CAM produced artificial teeth.

OBJECTIVES: To investigate whether artificial CAD/CAM processed (computer-aided design/manufacturing) teeth could be a feasible option for the production of dental in vitro models for biomechanical testing. MATERIAL AND METHODS: Disks (n = 10 per group) made from two different CAD/CAM-materials, one fiber-reinforced composite (FRC; Trinia, Bicon) and one polymethylmethacrylate-based resin (PMMA; Telio CAD, Ivoclar Vivadent), as well as bovine teeth (n = 10), were tested for their shear bond strength (SBS) and scored according to the adhesive remnant index (ARI). In addition, CAD/CAM-manufactured lower incisor teeth were tested for their ultimate load (Fu). RESULTS: With regard to SBS, both PMMA (17.4 ± 2.2 MPa) and FRC (18.0 ± 2.4 MPa) disks showed no significant difference (p = 0.968) compared to bovine disks (18.0 ± 5.4 MPa). However, the samples differed with regard to their failure mode (PMMA: ARI 4, delamination failure; FRC: ARI 0 and bovine: ARI 1.6, both adhesive failure). With regard to Fu, FRC-based teeth could withstand significantly higher loads (708 ± 126 N) than PMMA-based teeth (345 ± 109 N) (p < 0.01). CONCLUSION: Unlike PMMA-based teeth, teeth made from FRC showed sufficiently high fracture resistance and comparable SBS. Thus, FRC teeth could be a promising alternative for the production of dental in vitro models for orthodontic testing. CLINICAL RELEVANCE: CAD/CAM-processed teeth made from FRC enable the use of standardized geometry and constant material properties. Using FRC teeth in dental in vitro studies has therefore the potential to identify differences between various treatment options with rather small sample sizes, while remaining close to the clinical situation.

Early failures when using three different adhesively retained core build-up materials-a randomized controlled trial.

OBJECTIVES: To compare the failure rates for three different adhesively retained core build-up composites up to the incorporation of a permanent fixed dental prosthesis (FDP), and to identify potential failure risk factors. MATERIAL AND METHODS: A randomized controlled trial of 300 participants in need of a core build-up to restore a vital abutment tooth before prosthetic treatment was conducted. Participants were assigned by stratified block randomization to one of three study groups: Rebilda DC (RDC), Clearfil DC Core (CDC), or Multicore Flow (MF). Test teeth were prepared by use of the respective manufacturer's adhesive system. The total-etch technique was used for RDC and MF, and the self-etch technique for CDC. Participants were treated by dentists (n = 150) or dental students (n = 150). Failure rates of core build-ups before incorporation of FDPs were investigated using univariate and multiple logistic regression. RESULTS: The overall failure rate was 8% (n = 23). Rate differences between the three investigated groups did not reach statistical significance (p > 0.05). The mean time between placement of core build-ups and placement of fixed dental prostheses was 12.2 (SD: 14.2) weeks. Conversely, larger cavities (> 3 surfaces) and treatment by dental students were independently associated with an increased failure risk (p < 0.05). CONCLUSIONS: The main risk factors for early failure seem to be the size of the core build-up and clinical experience of the operator, whereas failure rates of core build-up materials combined with a self-etch approach seem to be similar to the rates of materials combined with the total-etch technique. CLINICAL SIGNIFICANCE: This research article should give clinicians an impression of the short-term performance of different adhesively retained core build-ups using different adhesive techniques/materials. Moreover, predominant influencing factors for the success or failure should be pictured.

Laboratory and clinical reliability of two spectrophotometers.

OBJECTIVE: To evaluate the repeatability, interexaminer, and interdevice reliability of two clinically applicable spectrophotometers under laboratory and clinical conditions. MATERIAL AND METHODS: For the in vitro part of the study, measurements were performed by the use of Vita Easyshade Advance 4.0 (ES-A) and the Easyshade V (ES-V) at identical positions on different shade tabs (3D-Master; Vita Zahnfabrik, Bad Säckingen, Germany). To test repeatability, one shade tab was measured 50 times by one operator. To determine interrater and interdevice agreement, two operators used both devices to perform 10 measurements on five different shade tabs. Clinical interdevice and interexaminer reliability was checked with a positioning jig used (15 participants). Measurement accuracy of both devices was evaluated for the recommended color of shade tabs. RESULTS: Repeatability of results from both Easyshades was excellent for all color components (maximum deviation between measurements was ≤0.1 units). Interrater agreement was also perfect (intraclass correlation, ICC = 1.000). Interdevice agreement was lower, but still good (ICC ≥ 0.834). In the clinical environment, interrater and interdevice agreements were similar (ICC > 0.964 and ICC > 0.873). Accuracy was satisfactory for both devices, with both observers in full agreement for nearly 80% of ratings. CONCLUSIONS: Both Easyshades produced reliable and accurate measurements and can therefore be recommended for clinical determination of tooth color. CLINICAL SIGNIFICANCE: The outcome of this study might help clinicians estimate the performance of a new digital shade determination device.

[Prevalence of temporomandibular disorders in seniors-Symptom-related analyses in younger and older seniors]. / Prävalenz kraniomandibulärer Dysfunktionen bei Senioren ­ symptombezogene Analysen bei jüngeren und älteren Senioren.

BACKGROUND: Temporomandibular disorders (TMD) are common in the general population even in old age. Information on the prevalence of TMD in older people is sparse. OBJECTIVE: To present prevalence values for symptoms and signs of TMD in old people according to the research diagnostic criteria for temporomandibular disorders (RDC/TMD). To compare prevalence values between the age groups of 60-74 years (younger seniors) and ≥ 75 years (older seniors). MATERIAL AND METHODS: Subjects of the interdisciplinary longitudinal study of adult development (ILSE), a representative sample of old people in Germany, were examined between 2014-2016. Subjects of the urban area of Leipzig were chosen to examine symptoms and signs of TMD. RESULTS: The most prevalent symptom was orofacial pain (13.0%) in the aged participants (n = 192). Temporomandibular joint (TMJ) sounds were the most prevalent sign with values up to 35.5%. Gender comparisons revealed higher prevalence values for the symptom headache/migraine as well as for the signs TMJ sounds (especially clicking sounds) and limited mouth opening in females. Regarding age groups, significant differences were only observed for self-reported headache/migraine. CONCLUSION: Orofacial pain was reported by 13.0% of the subjects and TMJ sounds were observed in every third participant. Similar prevalence values for TMD symptoms and signs in younger and older seniors were found.

Which factors influence the oral health of nursing-home residents with cognitive and motor impairments?

BACKGROUND: There is limited information available about the oral and denture hygiene and oral health of nursing-home residents with cognitive and motor impairments. AIMS: The purpose of this study was to identify factors influencing the oral and denture hygiene and oral health of nursing-home residents with cognitive and motor impairments. METHODS: The study was performed in nine nursing-homes in Germany. Sociodemographic and general data were collected for all participants (n = 150). The Clinical Dementia Rating (CDR) was used to identify the presence of dementia, and the Apraxia Screening Test (AST) was used to identify motor impairment. A comprehensive dental examination was also performed. This included the documentation of dental and denture status and the number of decayed, missing and filled teeth (DMFT). In addition, dental and denture hygiene were assessed using the Plaque Index (PI) and the Denture Hygiene Index (DHI). Univariate and multivariate regression models were used to analyse possible factors affecting the dependent target variables. RESULTS: In multivariate regression analysis, the factors that most strongly influenced greater PI were a lower number of medications taken (p = 0.018), poorer general health (p = 0.013) and the presence of dementia (p < 0.010). A more advanced age (p = 0.036) and longer nursing-home stay (p = 0.048) had a negative effect on the DHI. Furthermore, gender (p = 0.037, in favour of women), poorer general health (p = 0.003), presence of dementia (p = 0.003), and the absence of natural teeth (p = 0.028) influenced poorer oral health. The factors most strongly influenced greater number of missing teeth were a more advanced age (p = 0.021) and longer nursing-home stay (p = 0.015). In terms of fewer filled teeth, a shorter nursing-home stay (p = 0.002) was the factor most strongly influenced this. CONCLUSIONS: Poorer general health and the presence of apraxia and cognitive impairment are the main determinants for poorer oral hygiene and oral health among nursing-home residents. A longer nursing-home stay also seems to be relevant for oral health and denture hygiene.

Disposable plastic trays and their effect on polyether and vinyl polysiloxane impression accuracy-an in vitro study.

OBJECTIVES: To evaluate the dimensional accuracy of impressions taken by use of disposable stock plastic trays and to compare performance with that of metal trays. MATERIALS AND METHODS: From a metallic model incorporating three precision balls and three abutment teeth, one-step dual-phase polyether (PE) and vinyl polysiloxane (VPS) impressions were taken using either metal or disposable plastic trays (n = 10 for each of the resulting four test groups). Respective plaster cast scans were aligned with the reference dataset to evaluate global (distance and angle deviations) and local (trueness and precision) accuracy. Analyses of variance (ANOVA) were conducted to determine group differences. RESULTS: For all impression tray and material combinations, global accuracy was good (mean distance changes < 100 µm) with greatest deviations being observed for distances exceeding one quadrant of the dental arch. In general, distances measured in the plaster casts were too short. Only VPS impressions with plastic trays showed a different behavior with a large percentage of cross-arch distances exceeding the reference value. Mean local accuracy ranged between 6 and 14 µm (trueness), and 6 and 16 µm (precision). On abutment tooth level, metal trays were associated with a significantly better precision (p = 0.015). CONCLUSIONS: The observed distortions of the studied impression trays and materials are small and should enable satisfying clinical impression-taking. CLINICAL RELEVANCE: Cleaning and processing of metal trays before re-use are time-consuming. Especially for patients' management with single crowns and small fixed dental prostheses, disposable plastic trays can be a viable and cost-effective alternative.

Color stability of individually stained monolithic zirconia following occlusal adjustment.

OBJECTIVE: To meet esthetic requirements, monolithic zirconia can be stained by color-infiltration. However, adjustments of occlusal surfaces are often necessary, leading to demasking effects if too much of the color-infiltrated layer is removed. The effect of subsequent material removal on color stability of individually stained zirconia is analyzed here. MATERIALS AND METHODS: Thirty-six white zirconia disks were divided into three groups. Standardized staining strategies for tooth colors VITA A2, A3.5, and A4 were developed and applied to the disks. Samples were grinded in nine successive steps from 20 to 500 µm. A spectroradiometer was used to measure the color differences after each step. Regression analyses were performed for color differences from baseline as a function of depth of material removal. Depth of material removal resulting in color changes surpassing the acceptability threshold of ΔE00 = 1.8 was estimated using inverse prediction. RESULTS: Up to 500 µm material removal, color difference ΔE00 changes linearly with the depth of material removal (P < 0.05). Regression analyses showed coefficients of determination (R2 ) of 0.97 (VITA A2), 0.87 (VITA A3.5), and 0.96 (VITA A4). Acceptability threshold was surpassed at 62, 87, and 92 µm, respectively. CONCLUSIONS: Discolorations occur within clinically relevant occlusal adjustments of <100 µm. The effect is more severe with lighter, less saturated tooth colors. CLINICAL SIGNIFICANCE: Staining that is resistant to occlusal adjustments and abrasion is only possible if the staining solution infiltrates sufficiently deep into the ceramic structure. This study provides for the first time in the literature numerical values that describe the thresholds of acceptability of color differences in zirconia ceramics. These values are essential because they determine the extent of possible occlusal adjustments, and thus the color stability. Further research is necessary to improve the infiltration depth of staining solutions.

Long-term chipping and failure rates of implant-supported and combined tooth-implant-supported metal-ceramic and ceramic fixed dental prostheses: A cohort study.

STATEMENT OF PROBLEM: Combined tooth-implant-supported fixed dental prostheses have been associated with an increased risk of long-term failure. Furthermore, high chipping rates have been reported for ceramic fixed dental prostheses. However, clinical data are sparse. PURPOSE: The purpose of this observational cohort study was to evaluate the chipping and failure rates of metal-ceramic and ceramic implant-supported and combined tooth-implant-supported fixed dental prostheses. MATERIAL AND METHODS: Four hundred thirty-four fixed dental prostheses placed in 324 patients (mean age: 60.8 years) were selected from a prospective clinical long-term study comprising 213 implant-supported fixed dental prostheses, 66 implant-supported cantilever fixed dental prostheses, and 155 tooth-implant-supported fixed dental prostheses. Metal-ceramic fixed dental prostheses (n=260) were fabricated with a high noble metal alloy (n=225) or Co-Cr base metal alloy (n=35) frameworks. Ceramic fixed dental prostheses (n=174) were all zirconia based and had monolithic (n=68), completely veneered (n=43), or partially veneered frameworks (n=63). Kaplan-Meier curves were used to estimate the survival probability and the chipping-free survival rate of the fixed dental prostheses. RESULTS: During the observation period of 0.5 to 12.6 years (mean: 4.26 years), 17 fixed dental prostheses failed because of implant failure (n=6), tooth loss (n=5), major chipping (n=5), or abutment screw loosening (n=1). Survival probability was 96% after 5 years and 91% after 10 years. Cox regression analysis showed that age, sex, fixed dental prosthesis location, type of fixed dental prosthesis support, and fixed dental prosthesis material had no significant effect on fixed dental prosthesis failure. Chipping (n=61) was significantly affected by the framework material and type of veneer (P=.001). After 5 years, the greatest incidence of chipping (39%) was observed for zirconia fixed dental prostheses with a complete veneer compared with an 18% incidence of chipping for metal-ceramic fixed dental prostheses with a high noble metal framework. A lower incidence of chipping was observed for zirconia fixed dental prostheses with a partial veneer or monolithic design. CONCLUSIONS: Implant-implant-supported and combined tooth-implant-supported fixed dental prostheses have promising long-term survival rates. Chipping seems to occur less frequently in monolithic or partially veneered fixed dental prostheses than in fixed dental prostheses with complete veneers.

[Dental treatment in old age-When and what is indicated?] / Zahnärztliche Therapie im Alter ­ Wann ist was indiziert?

In the past few years the oral health of seniors has improved and more seniors retain their natural teeth until old age; however, the prevalence of oral diseases among seniors is still very high and a serious problem. Good oral health is, however, relevant for seniors as it influences the chewing function, the nutritional status and general satisfaction. In addition, diseases of the oral cavity show interactions with general health. The current article therefore provides an evidence-based overview of the oral health of seniors and highlights important relationships (nutritional status, oral health-related quality of life, general health). It also gives advice on when dental treatment may be indicated. Furthermore, instruments for assessing oral health, chewing function and oral health-related quality of life are presented and explained.

Clinical Performance of Posterior Inlay-Retained and Wing-Retained Monolithic Zirconia Resin-Bonded Fixed Partial Dentures: Stage One Results of a Randomized Controlled Trial.

PURPOSE: To prospectively compare the clinical performance of posterior inlay-retained and wing-retained monolithic zirconia fixed partial dentures (FPDs). MATERIALS AND METHODS: After simple randomization, 30 participants received either one inlay-retained (n = 15; mean age: 56.38 ± 12.70 years; 10 men [66.7%]) or one wing-retained (n = 15; mean age: 45.90 ±13.24 years; 7 men [46.7%]) FPD. The restorations, which predominantly replaced first molars, were fabricated from translucent, 3 mol% yttria-stabilized zirconia and attached with self-etching resin cement. Restorations and abutment teeth were clinically followed up for complications one week and 3, 6, and 12 months after cementation. Plaque and gingival scores, probing pocket depths, and attachment levels were recorded for the abutment and contralateral reference teeth both before treatment and during follow-up examinations. The restorations were also assessed in accordance with FDI World Dental Federation criteria. Statistical analyses were conducted with R (α = 0.05). An adaptive, 2-stage study design based on the incidence of failure-free survival in the groups after 12 months (stage 1) was implemented. Predefined decision rules were used to determine whether further recruitment (stage 2) would enable the detection of a statistically significant difference between the restoration designs with sufficient power. RESULTS: During 12 months, only one wing retainer debonded which required removal of the FPD. Failure-free survival was thus 93.3% for wing-retained and 100% for inlay-retained FPDs (log-rank test, p = 0.317). Moderate aftercare resulted in intervention-free rates of 78.8% and 86.7% for inlay-retained and wing-retained restorations, respectively (log-rank test, p = 0.605). Based on FDI World Dental Federation criteria, all restorations were acceptable at the 12-month follow-up (Fisher-Boschloo test, p = 0.161). Plaque, gingival, and periodontal scores remained practically unchanged from before treatment to the 12-month follow-up. Recruitment was stopped after stage 1 because, based on the small difference in the incidence of failure-free survival in the groups, it was accepted that it would not be possible to recruit the necessary number of participants to show a statistically significant difference between the retainer designs. CONCLUSIONS: Both inlay-retained and wing-retained monolithic zirconia resin-bonded FPDs performed well for the 12-month, short-term follow-up period.

Development of a German version of the Oral Health Assessment Tool.

BACKGROUND: Limited assessment tools for estimating the oral health of nursing home residents are available in the German language. AIMS: To develop a German version of the Oral Health Assessment Tool (OHAT) and to evaluate test-retest and inter-examiner reliability in use for the assessment of nursing home residents' oral health by caregivers before and after dental training. METHODS: The original English version of the OHAT was translated into German by a forward-backward translation process. Reliability assessments were conducted in a nursing home (n = 18) by independent application of the OHAT by two trained dentists and four professional caregivers. After receiving dental training, the caregivers repeated the OHAT with the same participants. Reliability analyses of single items were performed using Cohen's kappa statistics. Intra-class correlations were compiled to assess reliability of the total scores. T tests were used to compare percentage agreement, and under- and overestimation of findings between a reference dentist and the caregivers before and after the training unit. RESULTS: Specificity and sensitivity of the German OHAT were 87% and 86%. Test-retest reliability of the total OHAT score as estimated by the dentists was excellent (ICC 0.910; 95% CI 0.776-0.965). Before training, mean κ values between the reference dentist and caregivers ranged between 0.155 and 0.912, whereas the inter-examiner reliability of most items was only fair. After training, overall agreement between the dentist and the caregivers improved significantly from 62.1 to 83.1% (p < 0.001), as well as satisfying inter-examiner agreement for the single items. CONCLUSIONS: The German version of the OHAT is a reliable and valid tool for the assessment of oral health conditions of nursing home residents. When used by caregivers, instruction on the tool and practical training are mandatory to ensure reliable estimations. However, further studies with a larger sample size are encouraged to verify the outcomes of this study.

How reliable and accurate is the shade determination of premolars by spectrophotometry?

OBJECTIVES: To evaluate the reliability and accuracy of spectrophotometric shade determination of premolars and to compare the results with those for incisors. MATERIAL AND METHODS: Fifty-seven participants with natural maxillary incisors and premolars were recruited to investigate the research question. The colour of test teeth (incisors, n = 210; premolars, n = 192) was measured by use of the Vita Easyshade Advance (ES-A) and Vita Easyshade V (ES-V). Accuracy was evaluated by rating the shade tab matches recommended by the devices (scale, 1 = excellent match to 3 = mismatch). Inter-device reliability between the ES-A and ES-V for measurement of incisors and premolars was evaluated using intra-class correlation coefficients (ICC). The ratings for the accuracy of the devices were analysed using descriptive and bivariate statistics. A linear regression model was used to evaluate possible independent influencing confounders on the shade match. RESULTS: Inter-device agreement of the ES-A and ES-V for measurement of incisors and premolars was excellent for all colour components (ICC > 0.9). The accuracy of both devices was acceptable to excellent for incisors and premolars, although the ES-V was more accurate than the ES-A (p < 0.001). No significant difference in accuracy was detected between premolars and incisors (p = 0.182). The linear regression model confirmed the bivariate testing. CONCLUSIONS: The reliability and accuracy of spectrophotometric shade determination seem comparable for incisors and premolars. The recently introduced ES-V seems more accurate than its predecessor model. Further studies are needed to validate the results of this study.