BACKGROUND:Patients with craniomandibular dysfunction may experience changes in mandibular position over time when wearing occlusal splints continuously throughout the day and night. The aim of this study was to investigate whether similar changes can also be observed in healthy individuals who wear such splints exclusively at night. METHODS:The study included 13 healthy participants who were provided with maxillary stabilization splints worn only during night-time. Clinical evaluations were conducted after exactly 7 days, and the total study duration was 3 weeks. The maximal intercuspal position (MIP) as well as the centric condylar position (CR) were recorded in the condylar region of a measuring articulator. Additionally, the centric condylar position with the splint in place was determined several times using a thermoplastic registration material. The magnitude and direction of the positional differences were compared. RESULTS:The differences in mandibular position between centric condylar position (CR, wax registration records) and maximal intercuspal position (MIP, no interdental records) measured 0.74 ± 0.35 mm at the first and 0.74 ± 0.37 mm at the final session. The corresponding distances between all CR records obtained with the splints and MIP were 0.82 ± 0.39 mm. CONCLUSION:Within the investigated sample, night-time use of stabilization splints did not result in any change in mandibular position. A secondary finding was that occlusal adjustments were required during splint delivery, despite the use of facebows and registration procedures.

(1) Background: Repairing fractured provisional restorations may avoid refabrication, but success depends on substrate chemistry, repair protocol, and aging. This study evaluated shear bond strength (SBS) and failure behavior after chairside repair of PEMA-, PMMA-, and bis-acryl-based provisional materials. (2) Methods: In total, 380 specimens were prepared. Repairs used the substrate material, a dedicated repair system, or flowable composite without pretreatment or after a methacrylate repair primer, an MMA/Bis-GMA primer, or a multifunctional methacrylate coating. Half underwent 5000 thermocycles (5–55 °C). SBS was determined using a notched-edge test based on ISO 29022:2013, and failure modes were evaluated. An HC3-robust three-factor model was followed by Holm-adjusted Welch comparisons. (3) Results: A material × protocol × aging interaction occurred (p < 0.001). Homologous repair yielded 17.88–20.35 MPa for PEMA and 25.09–25.30 MPa for PMMA. Pretreatment improved composite repair across substrates. Pre-test failures affected 40.0% of PEMA and 13.3% of PMMA specimens but no bis-acryl specimens. Unprimed flowable composite produced complete pre-test failure with PEMA, low SBS with PMMA, and moderate SBS with bis-acryl. Thermocycling effects were protocol-dependent. (4) Conclusions: Conventional acrylics should be repaired homologously or after chemical conditioning, whereas flowable composite alone may be suitable for minor, non-load-bearing bis-acryl corrections.

OBJECTIVES:This longitudinal study used data from the 6th German Oral Health Study (DMS • 6) to determine the incidence of tooth loss and prosthetic treatment over a 9-year period in participants from the DMS • 6 cohort who were examined in 2014 (baseline) and reexamined in 2023 (follow-up). METHOD AND MATERIALS:The sample comprised 342 adults (43- to 52-year-olds at follow-up) and 373 seniors (73- to 82-year-olds at follow-up) who met the inclusion criteria for the DMS • 6 analysis set and for whom complete information on prosthetic treatments was available were included. The prevalence, extent, and incidence of tooth loss and prosthetic treatment were compared between baseline and follow-up. RESULTS:Over the 9-year observation period, the cumulative incidence of tooth loss among seniors was twice that among adults. The level of education influenced tooth loss: seniors with > 10 years of schooling remained unchanged, whereas those with ≤ 10 years exhibited an increase. The cumulative incidence of edentulism was 3.2% among seniors, and no adult was edentulous at any timepoint. Among adults, the prevalence of full dentition decreased from 44.0% at baseline to 37.6% at follow-up. The proportion of fixed-denture treatments increased by 11.1 percentage points in adults and decreased by 2.8 percentage points in seniors. However, the prevalence of implants increased in both cohorts. The incidence rates (per 100 person-years) of tooth loss indicate an accelerated loss rate in seniors (seniors: 10.0 vs adults: 4.1). The incidence of new implants was similar among adults and seniors (incidence rates: 1.1 and 1.4 per 100 person-years, respectively). CONCLUSION:The cumulative incidence of edentulism among seniors was low, and the increase in the frequency of implant treatment appeared to effectively compensate for tooth loss, with comparable rates in both age cohorts. School education had a pronounced impact on oral health and the need for prosthetic treatment. (Quintessence Int 2026;57(Suppl):S56-S65; doi: 10.3290/j.qi.b6955470).

PURPOSE:To investigate the neuromuscular position of the mandible in the fifth and final part of a comprehensive investigation of the positions of the temporomandibular joint condyles. MATERIALS AND METHODS:The neuromuscular condylar positions were recorded by four independent operators in 81 fully dentate subjects with healthy oral function using a central bearing point system and rapid closing movements. The most frequent adduction point was determined, and the recordings were repeated twice for each subject. The subjects' maxillary casts were mounted in an articulator using an individual facebow transfer, and subsequently the mandibular casts were mounted with a central bearing point registration on the tip of the Gothic arch, ie, in centric condylar position (CR). A custom-made electronic measuring articulator was used to determine the spatial distance between the condyles in centric relation, maximal occlusion, and the newly determined neuromuscular position. RESULTS:The reproducibility of the neuromuscular registrations was on average 0.52 ± 0.16 mm (range 0.04 to 2.53 mm) with the right and left side averaged. The average spatial distance of the condyles between maximal intercuspal position (MI) and neuromuscular position was 0.88 ± 0.30 mm (range 0.12 to 5.98 mm), again averaged for the right and left sides, whereas that between the CR and the neuromuscular position was 0.83 ± 0.27 mm (range 0.10 to 7.89 mm). CONCLUSIONS:The neuromuscular mandibular position is neither identical to MI nor to CR. It can therefore be concluded that the registration of the neuromuscular adduction field should not be recommended for prosthodontic restorations in dentate or edentulous patients.

OBJECTIVES:Oral health is a key determinant of overall wellbeing and general health, particularly in seniors who are often affected by multimorbidity and polypharmacy and may also require nursing care. The German Oral Health Studies (DMS) are population-representative epidemiologic surveys that assess oral health in Germany. This study aimed to clarify the prevalence, incidence, and progression of oral diseases in seniors using longitudinal data from the DMS • 6 cohort. METHOD AND MATERIALS:The longitudinal analyses were based on data from 373 individuals who had previously participated in DMS V in 2014 as 65- to 74-year-olds (baseline) and were reexamined in 2023 as 73- to 82-year-olds (follow-up). Data on social demographics, disability, need for care, morbidity, oral functional capacity, and oral diseases were collected through social science interviews and clinical examinations. RESULTS:The mean age of the participants at baseline and follow-up was 69.4 ± 2.9 years and 78.3 ± 3.0 years, respectively. From baseline to follow-up, the mean number of missing teeth (excluding third molars) and incidence of edentulism increased. Furthermore, the number of replaced and unreplaced missing teeth both increased, and the mean number of missing teeth replaced with removable dentures increased. The caries incidence increased slightly, and periodontal health deteriorated. The number of teeth with probing depth (PD) ≥ 4 mm increased, whereas that of teeth with PD ≥ 6 mm remained unchanged. The proportion of participants requiring nursing care increased, and control-oriented dental service utilization decreased. CONCLUSION:Seniors lost approximately two teeth during the 9-year observation period. However, many teeth were retained at an advanced age. The challenges faced by people in higher ages are not limited to dental therapy but are complemented by lifelong dental care. Implementing preventive dental requirements during disease-related transition processes in senior women and men is challenging for the dental profession, as good oral health despite frailty and care needs must in part also be organized and ensured outside the dental practice. (Quintessence Int 2026;57(Suppl):S66-S75; doi: 10.3290/j.qi.b6955454).

Objectives The aim of the present study was to investigate, whether polyetherketoneketone (PEKK) secondary crowns could be considered as alternative to gold standard in terms of their physical properties and manufacturing costs.Methods An upper jaw model with six implants was used. Frameworks with either 6 PEKK- or 6 electroplated secondary crowns were cemented in a wear simulator. A total of 20 specimens (10 PEKK, 10 gold) run 10,000 cycles in the wear simulator with a lubricant. Additionally, 10,000 cycles in the thermocycling baths with 5 degrees C and 55 degrees C have gone through, before running extra 10,000 cycles in the wear simulator again. Finally, the abutments were analysed for signs of wear under the electron microscope.Results The mean pulling out force value for PEKK was 21 N. For the electroplated gold secondary crowns an average of 19 N was measured. Multiple fluctuations were observed in the gold series of tests. After 20,000 cycles in the wear simulator and 10,000 cycles in the thermocycling machine, there were no major losses to be measured in terms of wear for both materials. In the microscopic analysis of the abutments, traces of wear could be seen in pull-out direction, mainly in the gold samples.Conclusions PEKK secondary crowns have lower costs, more stable retention force values and are easier to produce than the gold standard. On average, the pull-out force values were 11 N higher than recommended.

OBJECTIVES:Oral health plays a central role in overall well-being, including in the elderly. The demographic transition and its effects are resulting in a higher proportion of older people, both with and without care requirements. This paper provides an overview of the dental situation of the elderly from the 6th German Oral Health Study (DMS • 6). METHOD AND MATERIALS:DMS • 6 is a population-representative oral epidemiologic study that surveys oral health in Germany. Data from 797 younger seniors aged 65 to 74 were collected by calibrated examiners. The methodology remains largely consistent with that of the previous studies. RESULTS:Among the younger seniors (65- to 74-year-olds), edentulism has more than halved to 5.0% compared to the Fifth German Oral Health Study (DMS V) (12.4% in 2014). The mean number of missing teeth (8.6) decreased further, compared to DMS IV (14.1) and DMS V (11.1). At 18.8 teeth, the FST Index (number of filled or sound teeth) has shown improvement compared to the previous studies (DMS IV, 13.6; DMS V, 16.4). The root caries (59.1%) increased compared to DMS IV (28.0%). Caries experience (decayed, missing, filled teeth [DMFT]: 17.6), in contrast, hardly changed from DMS V (17.7). Half of 65- to 74-year-olds were diagnosed with moderate periodontitis (49.4%) and almost a third (30.4%) with severe periodontitis. In younger seniors with care requirements, therapeutic capability was greatly reduced for almost half (47.4%) and oral hygiene ability for one fifth (18.5%). CONCLUSION:The prevalence of tooth loss and edentulism among younger seniors in Germany continues to decline. Due to further morbidity compression, the challenges of dental treatment lie in the continuous treatment of younger seniors to prepare them for older stages of life.

(1) Background: Early-stage bone resorption following implant placement can significantly impact the long-term success of implants. This study evaluates whether a fully digitally planned implant position based on the E-point concept, along with guided profiling of the supracrestal complex, contributes to improved stability of peri-implant bone levels. (2) Methods: 29 implants were placed in 27 patients utilizing both immediate (Group 1; n = 19) and delayed placement (Group 2; n = 10) protocols. Implant position and emergence profile were preoperatively determined and consistently executed through guided surgery and CAD/CAM-fabricated restorations. Due to the subcrestal positioning of the implant, a corresponding bone profiler with a guide pin was used to shape the emergence profile and prevent the provisional restoration from impinging on the proximal bone. Provisional restorations were immediately placed to support the emergence profile. Bone level changes were documented radiographically over a two-year period. The first Bone-to-Implant Contact Level (∆ fBIC), change in highest approximal Bone Level (∆ haBL), and formation of an emergence profile width (WEP) were measured. (3) Results: All implants and restorations survived after two years, no significant change in first Bone-to-Implant Contact Level (∆ fBIC = 0 ± 0.02 mm), no change in highest approximal Bone Level (∆ haBL) of −0.23 mm ± 0.71 mm, and formation of an emergence profile width (WEP) averaging 0.18 ± 0.19 mm. (4) Conclusions: Despite the initial stress on the bone caused by bone profiling, guided implant placement and bone shaping, supported by an immediate provisional, have a positive effect on peri-implant bone stability.

Background: Primary implant stability is a critical factor for successful osseointegration and long-term implant success. This study investigates the impact of drilling protocol modifications on primary stability, considering different bone qualities and implant macro-designs, lengths, and diameters. Material and Methods: Three implant designs—two parallel-walled and one tapered—were tested with diameters ranging from 3.4 to 5.2 mm and lengths from 7.5 to 14.5 mm. Implants were placed in polyurethane foam blocks simulating different bone densities (10, 15, 25, and 35 PCF). A standard drilling protocol was used in all groups, with modifications based on bone quality: overpreparation in dense bone and underpreparation in softer bone. Primary stability was evaluated using insertion torque (IT). The optimal IT range was defined as 25–50 Ncm, based on clinical guidelines for immediate loading. The influence of drilling protocol adaptations on stability parameters was assessed. Results: Insertion torque was primarily influenced by bone density and implant diameter, with implant length playing a minor role. In dense bone (D1, D2), underpreparation improved torque values, especially in smaller implants, while overpreparation reduced them. The highest torques occurred with 5.2 mm implants, sometimes exceeding 80 Ncm. Standard protocols did not consistently achieve optimal torque across implant types. In soft bone (D3), underpreparation—particularly with tapered implants—was modestly beneficial. In very soft bone (D4), none of the protocols reliably reached the desired torque range. Conclusions: Adapting drilling protocols to bone density improves insertion torque, especially with wider implants and in denser bone. Underpreparation is generally more effective than overpreparation. However, in very soft bone, neither implant geometry nor drilling adaptations reliably achieve optimal primary stability, highlighting the need for additional strategies.

OBJECTIVES:The German Oral Health Study (DMS) is a series of consecutive studies designed to assess the oral health status of adults, seniors, and children in Germany. DMS is a major program of the Institute of German Dentists (Institut der Deutschen Zahnärzte) with the aim to produce health statistics for Germany. Tooth loss, edentulism, and prosthetic care have considerable socioeconomic significance; it is the aim of this paper to report findings on these aspects. METHOD AND MATERIALS:The survey combines interviews and clinical examinations. Previous DMS studies focused primarily on tooth loss, edentulism, and prosthetic care. In the DMS • 6 survey, the condition of removable dentures and need for adjustments were additionally recorded, as well as necessary repair measures that were grouped according to their complexity (chairside or laboratory). RESULTS:The prevalence of edentulism decreased considerably compared to that in the Fifth German Oral Health Study (DMS V) in 2014. Among younger adults (35- to 44-year-olds), the prevalence of edentulism was negligible, with an average of 26.6 teeth present. The younger senior group (65- to 74-year-olds) had an average of 19.3 teeth; the prevalence of edentulism was 5%, which is a reduction of > 50% compared to 2014 (12.4%). Lower education status was an important prognostic factor for tooth loss. Owing to the low prevalence of edentulism in younger adults, removable dentures were not prevalent in this age group, whereas combined fixed-removable dentures were most frequently used in seniors. Regarding the type of denture, a shift towards fixed as well as implant-supported types was observed. Of the removable dentures, 50% to 60% were in a very good or good clinical condition. Problems were mainly identified with simple acrylic dentures. Nonetheless, participants' satisfaction with removable dentures was extremely high, and the dentures were used almost continuously. CONCLUSION:The most important finding in this study is the continued significant decline in the prevalence of complete edentulism among seniors that suggests a further reduction in edentulism in the future with an estimate of around 4% in 2030. The shift observed in primary prosthetic care from removable to fixed prostheses as well as the increasing prevalence of implants placed are positive developments. The data revealed further compression of morbidity compared to DMS V. Complete edentulism declined, and fixed partial dentures, including implant-supported prostheses, were increasingly used. Lower education status was an important predictor for tooth loss.

Background: Virtual simulators are increasingly being introduced in dental education. This study investigates whether virtual simulators offer comparable or superior educational efficacy when compared to traditional phantom simulators. Materials and Methods: Participants were randomly allocated into groups: Virtual Preparation (SIM; n = 30) and Traditional Preparation (FRA; n = 30). Students were tasked with preparing tooth 36 for a full-cast crown during free practice for four days. Faculty staff provided feedback to both groups. Examinations were administered and graded by three examiners (preclinical and clinical consultants and a dental surgery consultant). Additionally, a survey was conducted to assess each training concept. Results: The FRA group achieved significantly better grades in the preparation exam evaluations by all three examiners, compared to the SIM group. Interrater reliability showed only moderate agreement, with the clinical examiner giving better grades than the other two. The questionnaire results indicate that while participants managed with the virtual system, they preferred the analog system for exams and patient preparation. Conclusion: Virtual simulators do not seem to be as good when it comes to practicing for a preparation exam or clinical preparation, especially for unexperienced students. However, they still appear to be useful as an additional tool for introducing students to the topic of preparation.

Objective: The aim of the present study was to evaluate the long-term clinical survival and success of chairside-fabricated single-tooth monolithic zirconia restorations on posterior teeth using the speed sintering process. Materials and Methods: Between 2012 and 2022, 250 single-tooth crowns were fabricated for 193 patients using the CEREC® chairside workflow. Restorations were fabricated from monolithic 3Y-TZP zirconia (InCoris TZI, Dentsply Sirona©, Bensheim, Germany) as full-contour crowns. The same clinician performed all procedures. Luting was performed using self-adhesive resin-based cements or glass ionomer cement. Retrospective analysis was conducted, defining survival as crowns still in function regardless of any interventions, and success as crowns that remained functional without the need for intervention. Statistical analysis was performed using Kaplan–Meier analysis, considering “refabrication” and “intervention” as endpoints. Results: Of the 250 crowns, a total of 162 (64.8%) crowns showed success. Over the whole observation period, 44 crowns (17.6%) required refabrication, and 88 (35.2%) required intervention. Mean survival without refabrication was 7.43 years, with a 5- and 7.5-year survival of 86.9% and 76.6%. The mean survival without intervention was 6.5 years, with a 5- and 7.5-year survival of 70.8% and 59.9%. Conclusions: Under appropriate technical conditions, chairside-fabricated 3Y-TZP zirconia single-tooth crowns represent a viable fabrication method. Neither the cementation mode nor the crown position—whether on premolars or molars—significantly impacted the survival rates.

Background: Classic endocrowns made of dental ceramics are considered a promising alternative to traditional post-endodontic restorations. The use of circular ferrules in endocrowns is a topic of controversial discussion. Therefore, the present study aims to evaluate the effect of ferrule design and cementation mode on the fatigue resistance of zirconia endocrowns. Methods: Eighty human molars were divided into four groups (n = 20): NFC (no-ferrule, conventional cementation), NFA (no-ferrule, adhesive luting), FC (ferrule, conventional cementation) and FA (ferrule, adhesive luting). Both the classic and the modified endocrown preparation with a two-millimeter ferrule design were carried out. Endocrowns were fabricated from zirconia using the CEREC system. After thermocycling, specimens were loaded according to the step-stress test up to 1500 N. Results: Failure rate was low; 88.8% of total specimens passed the step-stress test. Fractures were distributed between all groups; no significant differences in fatigue resistance were detected for preparation design and cementation mode. Conclusions: Endocrowns appear to be a promising concept for endodontically treated molars. Ferrule and also cementation mode have only a minor influence on fatigue resistance of zirconia endocrowns. However, at very high forces, the marginal area of the ferrule represents a weak point.

Purpose: To investigate if and how the positions of condyles in centric relation (CR) varied from each other using different CR records. Materials and Methods: Condylar positions in CR were repeatedly recorded by four licensed clinicians in 81 stomatognathically healthy, fully dentate subjects with six different types of CR records. The maxillary casts were mounted in articulators after individual facebow transfer, and the mandibular casts were mounted with a central bearing point (CBP) registration on the tip of the Gothic arch. Mean values from three registrations of the centric condylar positions with each of the six methods were calculated, and comparative calculations were made. Results: The median spatial distances of the condylar positions between the CBP and all other CR records was 0.73 ± 0.24 mm (0 to 3.19 mm). The median spatial values between the condylar positions of the different CR records ranged from 0.48 to 0.79 mm. Statistically, the positions of almost all types of registration were slightly different from each other. Conclusion: Different CR records reproduce slightly different positions of the mandible, which is especially true for CBP registration, whereas reproducibilities and SDs between registrations are similar. Unrefined wax-wafer registrations using bimanual manipulation have proven particularly successful with regard to precision and time requirements, as has CBP registration with regard to condylar position.

Abstract Background Sublingual varices (SV) and their predictive potential for other clinical parameters is a much studied topic in oral medicine. SVs have been well studied as predictive markers for many common diseases such as arterial hypertension, cardiovascular disease, smoking, type 2 diabetes mellitus and age. Despite many prevalence studies, it is still unclear how the reliability of SV inspection affects its predictive power. The aim of this study was to quantify the inspection reliability of SV. Methods In a diagnostic study, the clinical inspection of 78 patients by 23 clinicians was examined for the diagnosis of SV. Digital images of the underside of the tongue were taken from each patient. The physicians were then asked to rate them for the presence of sublingual varices (0/1) in an online inspection experiment. Statistical analysis for inter-item and inter-rater reliability was performed in a τ-equivalent measurement model with Cronbach's $$\alpha$$ α and Fleiss κ. Results The interrater reliability for sublingual varices was relatively low with κ = 0.397. The internal consistency of image findings for SV was relatively high with α≈ 0.937. This shows that although SV inspection is possible in principle, it has a low reliability R. This means that the inspection finding (0/1) of individual images often cannot be reproduced stably. Therefore, SV inspection is a difficult task of clinical investigation. The reliability R of SV inspection also limits the maximum linear correlation $${r}_{max}$$ r max of SV with an arbitrary other parameter Y. The reliability of SV inspection R = 0.847 limits the maximum correlation to $${r}_{max}$$ r max (SV, Y) = 0,920—a 100% correlation was a priori not achievable in our sample. To overcome the problem of low reliability in SV inspection, we propose the RA (relative area) score as a continuous classification system for SV, which normalises the area of visible sublingual veins to the square of the length of the tongue, providing a dimensionless measure of SV. Conclusions The reliability of the SV inspection is relatively low. This limits the maximum possible correlation of SV with other (clinical) parameters. SV inspection reliability is an important indicator for the quality of SV as a predictive marker. This should be taken into account when interpreting previous studies on SV and has implications for future studies. The RA score could help to objectify the SV examination and thus increase its reliability.

Objectives: Although the use of short implants is becoming more common for patients with atrophic alveolar ridges, their use is still quite limited. This is due to the lack of data of long-term survival compared to standard-length implants. The aim of this study was to determine the load in the bone and implant system with different superstructures.Methods: Three kinds of prosthetic restorations were created on short implants based on CT-Data. Two short implants with different macro-geometries were used. The implants were inserted in idealised posterior lower mandibular segments and afterwards restored with a crown, a double splinted crown, and a bridge.Results: The analysis was performed under load of 300 N either divided between a mesial and distal point or as a point load on the pontic/mesial crown. The different design of the implant systems had a noticeable influence on the stress in the cortical bone, in the implant system, and the displacement of the superstructure as well.Conclusions: Compared with implants of standard length, higher stresses were observed, which can lead early failure of the implant during the healing period or a late cervical bone resorption. Precise indications are essential for short implants to avoid the failure of short implants.

(1) Background: Primary implant stability is vital for successful implant therapy. This study explores the influence of implant shape, length, and diameter on primary stability in different bone qualities. (2) Methods: Three implant systems (two parallel-walled and one tapered) with various lengths and diameters were inserted into polyurethane foam blocks of different densities (35, 25, 15, and 10 PCF) using standard drilling protocols. Primary stability was assessed through insertion torque (IT) and resonance frequency analysis (RFA). Optimal ranges were defined for IT (25 to 50 Ncm) and RFA (ISQ 60 to 80). A comparison of implant groups was conducted to determine adherence to the optimal ranges. (3) Results: Implant macro-design, -length, and -diameter and bone block density significantly influenced IT and RFA. Optimal IT was observed in 8/40 and 9/40 groups for the parallel-walled implants, while the tapered implant achieved optimal IT in 13/40 groups (within a 25–50 Ncm range). Implant diameter strongly impacted primary stability, with sufficient stability achieved in only one-third of cases despite the tapered implant’s superiority. (4) Conclusions: The findings highlight the need to adapt the drilling protocol based on diverse bone qualities in clinical practice. Further investigations should explore the impact of these adapted protocols on implant outcomes.

Background When dental patients seek care, treatments are not always successful,that is pa-tients' oral health problems are not always eliminated or substantially reduced. Identifying these patients (treatment non-responders) is essential for clinical decision-making. Group-based trajectory modeling (GBTM) is rarely used in den-tistry, but a promising statistical technique to identify non-responders in particu-lar and clinical distinct patient groups in general in longitudinal data sets. Aim Using group-based trajectory modeling, this study aimed to demonstrate how to identify oral health-related quality of life (OHRQoL) treatment response patterns by the example of patients with a shortened dental arch (SDA). Methods This paper is a secondary data analysis of a randomized controlled clinical trial. In this trial SDA patients received partial removable dental prostheses replacing missing teeth up to the first molars (N = 79) either or the dental arch ended with the second premolar that was present or replaced by a cantilever fixed dental prosthesis (N = 71). Up to ten follow-up examinations (1-2, 6, 12, 24, 36, 48, 60, 96, 120, and 180 months post-treatment) continued for 15 years. The outcomeOHRQoL was assessed with the 49-item Oral Health Impact Profile (OHIP). Ex-ploratory GBTM was performed to identify treatment response patterns. Results Two response patterns could be identified - "responders" and "non-responders." Responders' OHRQoL improved substantially and stayed primarily stable over the 15 years. Non-responders' OHRQoL did not improve considerably over time or worsened. While the SDA treatments were not related to the 2 response patterns, higher levels of functional, pain-related, psychological im-pairment in particular, and severely impaired OHRQoL in general predicted a non-responding OHRQoL pattern after treatment. Supplementary, a 3 pattern approach has been evaluated. Conclusions Clustering patients according to certain longitudinal characteristics after treatment is generally important, but specifically identifying treatment in non-responders is central. With the increasing availability of OHRQoL data in clinical research and regular patient care, GBTM has become a powerful tool to investi-gate which dental treatment works for which patients.

The objective of this study was to evaluate the impacts of different sandblasting procedures in acid etching of Ti6Al4V surfaces on osteoblast cell behavior, regarding various physicochemical and topographical parameters. Furthermore, differences in osteoblast cell behavior between cpTi and Ti6Al4V SA surfaces were evaluated. Sandblasting and subsequent acid etching of cpTi and Ti6Al4V discs was performed with Al2O3 grains of different sizes and with varying blasting pressures. The micro- and nano-roughness of the experimental SA surfaces were analyzed via confocal, atomic force and scanning electron microscopy. Surface free energy and friction coefficients were determined. hFOB 1.19 cells were seeded to evaluate adhesion, proliferation and osteoblastic differentiation for up to 12 d via crystal violet assays, MTT assays, ALP activity assays and Alizarin Red staining assays. Differences in blasting procedures had significant impacts on surface macro- and micro-topography. The crystal violet assay revealed a significant inverse relationship between blasting grain size and hFOB cell growth after 7 days. This trend was also visible in the Alizarin Red assays staining after 12 d: there was significantly higher biomineralization visible in the group that was sandblasted with smaller grains (F180) when compared to standard-grain-size groups (F70). SA samples treated with reduced blasting pressure exhibited lower hFOB adhesion and growth capabilities at initial (2 h) and later time points for up to 7 days, when compared to the standard SA surface, even though micro-roughness and other relevant surface parameters were similar. Overall, etched-only surfaces consistently exhibited equivalent or higher adhesion, proliferation and differentiation capabilities when compared to all other sandblasted and etched surfaces. No differences were found between cpTi and Ti6Al4V SA surfaces. Subtle modifications in the blasting protocol for Ti6Al4V SA surfaces significantly affect the proliferative and differentiation behavior of human osteoblasts. Surface roughness parameters are not sufficient to predict osteoblast behavior on etched Ti6Al4V surfaces.

Background: The majority of complete dentures are still conventionally manufactured using a flask-and-pack technique. However, the polymerization process may introduce a distortion of the denture body. The aim of this study was to evaluate the three-dimensional fit of the posterior palatal seal of maxillary complete dentures with the original impression, and to give recommendations for scraping. Methods: Four autopolymerising resins were used to manufacture 40 palatal plates each for high, medium and flat palates (total n = 120). The misfit was captured by taking a reline impression with a highly fluid silicone, the dimensions of which were measured with a flat-bed scanner. Results: The shape of the palate had a significant impact (median p = 0.0435), but not the resin type (median p = 0.2575). It was largest for the flat palate and smallest for the high palate. The largest misfit was observed in the palatal midline area (flat-palate average median: 685 µm; high and medium palates: 620 µm) decreasing towards the lateral and anterior regions. Conclusions: The results suggest compensating for the palatal misfit that occurs with autopolymerising resins by scraping a postdam of an approximately 0.7 mm depth to the master cast, decreasing towards the anterior and lateral areas. In high and medium palates, the scraping could be less pronounced.