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Introduction: The use of digital dentistry is rapidly increasing in prosthodontics. However, most dental students are not familiar with applying digital technologies in dental clinics. Thus, the aim of the current study was to assess the perception of dental students at different educational years towards digital impressions in comparison to conventional impressions., Materials and Methods: A cross-sectional questionnaire-based study was conducted on various educational years of dental students in the College of Dentistry, Imam Abdulrahman Bin Faisal University, between February and April 2023. The students had performed at least one intraoral scan (Trios 3shape) and another conventional polyether impression for phantom casts/patients. The questionnaire assessed students' perceptions of digital impressions using a 5-point scale ranging from strongly agree to strongly disagree. Mann-Whitney U and Kruskal-Wallis tests were used to compare students' perceptions of digital impressions according to gender and educational year, respectively., Results: The study included 122 students. About 55% were females with a mean (SD) age = 22.51 (3.36). Most students thought that digital impressions are faster and more user-friendly compared to conventional impressions. Significantly more female students thought that the handpiece was too big for intraoral use (p = 0.04) and that the process of the software was time-consuming and complicated. In general, higher educational year students were more satisfied with the digital impressions than lower educational year students., Conclusions: Digital impressions were perceived by most students as being faster and easier than conventional ones. However, male students and those with higher educational years showed better perception of digital impression., (© 2024 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Introduction: In every prosthetic treatment, the final purpose of the restoration is to restore function and esthetics for the patient, respecting biology and anatomical parameters. Regarding full coverage restorations, there are some factors to take into consideration: like the finish line (chamfer, shoulder, featheredge, etc.), the management of the provisional restoration and tissue healing, the material for the final restoration, and the impression technique. All these aspects will determine the treatment process and its possible results. In recent years, vertical preparation and more specifically biologically oriented preparation technique has generated great interest since its introduction in prosthodontics, changing the periodontal tissues, and providing long-term stability., Materials and Methods: With this technique, the objective is to change the position of the gingival margin, moving it more apically or coronally, depending on the modifications of the provisional. The relining of the provisional is a fundamental step of this technique: the intrasulcular part of the provisional is modified giving a new emergence profile and providing an augmentation of the tissue in the healing process., Discussion: In vertical preparation, there is no predetermined margin. The dental technician should position the finish line more apically or coronally, depending on the depth of the sulcus and on the esthetic needs. Ceramic restorations should not invade the epithelial attachment, otherwise it may cause biological and mechanical problems, repetition of the impression, and of the crown restoration, which lead to increased clinical and laboratory time usage as well as expenses. One challenge is communicating the shape and contour of the temporary restoration to the dental lab to ensure accurate information for the final restoration., Conclusion: Finally, the objective of this article is to describe a technique for transferring all necessary information of the provisional and obtaining a predictable result for the final restoration by using an intraoral scanner system and the fabrication of two 3D printed prototypes. One for the final volume of the crowns and the other for the finish line position., Clinical Significance: The fabrication of 3D printed prototypes allows for a more predictable final restoration, reducing possible communication errors between clinician and technician when restoring with biologically oriented preparation technique. In any esthetic treatment where the restoration does not have a predetermined margin, it is possible with this additional clinical step to provide a more esthetic outcome., (© 2024 Wiley Periodicals LLC.)

Purpose: This study describes efficiency of diagnostic, image-based, and impression-based fitting methods by eye care providers who prescribe scleral lenses (SL) for patients with keratoconus., Methods: An electronic survey was distributed to eye care providers with an interest in SL fitting. Demographic data including practice modality, country of residence, and fitting volume were collected. Efficiency of each fitting method (diagnostic, image, and impression-guided) was queried including time required for initial evaluation, number of lenses ordered, and number of office visits required. Practitioners with access to image and impression-based technology were also asked time required to acquire data and to estimate the percentage of time a lens could be manufactured from the initial images or impressions., Results: 423 practitioners who prescribe SL for patients with keratoconus reported completing a median [IQR] 100 [280] SL fittings. There was no difference in the median time required for initial evaluation (30 min; p = 0.5) or median number of lenses ordered during the fitting process (2 lenses; p = 0.2) between diagnostic, image-based, or impression-based SL fitting methods. Median time to acquire initial images was 10 [7] minutes and 15 [10] minutes to obtain impressions. Images obtained were adequate to order an initial lens 80 [45]% of the time while initial impressions were adequate 90 [40]%., Conclusion: In this study, practitioner-reported efficiency of SL fitting was similar between diagnostic, image-based and impression-based methods for patients with keratoconus., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

An esthetic peri-implant soft tissue contour is a critical element of the success of implant restorations in the esthetic zone. Once the optimal transmucosal soft tissue profile is formed, it needs to be accurately replicated on the master cast. This clinical technique involves the utilization of a silicone putty positioning index placed in the patient's mouth to accurately duplicate the external contour of teeth and soft tissue. By combining this positioning index with the implant-supported interim crown, the 3D-printed initial cast, which was used to fabricate the interim crown, can be conveniently and efficiently transformed into a definitive master cast., (© 2023 The Authors. Journal of Prosthodontics published by Wiley Periodicals LLC on behalf of American College of Prosthodontists.)

Objective: This study investigated how the number of images collected for digital measurements in dentistry affects accuracy compared with traditional methods. Methods: A Frasaco maxillary model was scanned using a SHINING 3D AutoScan-DS-MIX dental 3D scanner to create an STL file. The maxilla was molded 10 times using polyvinyl siloxane (Zhermack Elite HD+) to produce plaster models, which were scanned with the same reference scanner to generate 10 STL files. The Frasaco model was scanned 10 times, capturing images in intervals of 800-1000, 1000-1200, and 1200-1500 using a 3Shape TRIOS 3 intraoral scanner, creating additional STL files. These were analyzed with reverse engineering software. Results: The most accurate measurements were obtained using 1200-1500 images. Conventional impression techniques performed significantly worse. There was a significant difference between the groups Digital 1200-1500 and Plaster ( p < 0.001) and between Digital 800-1000 and Plaster ( p = 0.007). No significant difference was found when the digital groups were compared among themselves. There was also no significant difference between the Plaster and Digital 1000-1200 groups. To compare precision values that were normally distributed across three or more methods, a one-way ANOVA was used. Trueness values that were not normally distributed with three or more methods were compared employing the Kruskal-Wallis test. Conclusions: Different image counts affect digital measurement accuracy. The most accurate measurements were obtained when collecting 1200-1500 images. Conventional impression techniques were shown to perform significantly worse than digital impression.

Purpose: To evaluate the dimensional accuracy of implant impressions obtained using five different tray types and two techniques., Materials and Methods: A partially dentate maxillary Kennedy Class II model was created as a reference model through 3D printing. Then, implant analogs 4.3 mm in diameter were placed at the first premolar, first molar, and second molar sites. Five types of trays were used to create impressions: (1) metal stock trays, (2) plastic stock trays, (3) custom trays fabricated using liquid crystal display (LCD), (4) custom trays fabricated using fused deposition modeling (FDM), and (5) custom trays fabricated using urethane dimethacrylate (UDMA) resin. Open and closed tray techniques were also compared. In total, 150 impressions were obtained. The reference model and impressions were scanned using a laboratory scanner. Additionally, the positional and angular deviations of implants with different tray types and techniques were evaluated using the superimposition method., Results: There was no statistically significant difference (P > .05) between the impression accuracy with the different tray types and impression techniques. The angular deviations with plastic and UDMA trays were greater than those with metal, FDM, and LCD trays. Angular deviation at the second molar was greater when using closed plastic trays compared to open plastic trays. The highest and lowest positional deviations were observed at the first molar implant with an open plastic tray impression (mean ± SD of 62.46 ± 28.54 mm) and a closed LCD tray impression (36.59 ± 29.93 mm). The greatest angular deviation was observed with an open FDM tray impression at the first premolar implant (0.067 ± 0.024 degree), and the lowest angular deviation was observed with a closed metal stock tray impression at the second molar implant (0.039 ± 0.025 degree). Statistical differences were detected using the Mann-Whitney U test for paired groups and the Kruskal-Wallis test for groups with more than three comparisons (P > .05)., Conclusions: Plastic and metal stock trays or conventional and 3D-printed custom trays can be used to obtain implant impressions for maxillary partially edentulous arches with similar dimensional accuracy. The five tray types and two techniques may be safely used to obtain impressions of partially edentulous maxillary arches with three implants.

Aim: The aim of this study was to compare the accuracy of full-arch conventional implant impressions using two different materials (A-silicone and polyether) to full-arch digital implant impressions produced from two intraoral scanning devices., Materials and Methods: A master model was fabricated representing an edentulous mandible with four implants with internal connection placed at the sites of canines and first molars. The anterior implants were parallel to the residual ridge, while the two posterior implants had an angulation of 15° to the distal and 15° to the lingual respectively. The conventional technique was performed with open-tray of non-splinted impression copings. Two different impression materials were used, A-silicone and polyether at monophase medium body consistencies. The digital impressions were obtained with the use of two different intraoral scanners, after the connection of scan bodies. A total of 10 impressions were produced for each of the four experimental groups. The conventional models as well as the master model were digitized using a high-resolution laboratory scanner. The STL files of the models and of the intraoral impressions were imported in a powerful superimposition software, for the conduction of measurements in pairs of files. The software calculated the 3D deviations, as well as the linear and angular displacements among scan bodies at the digital files. For "trueness" measurements every STL file of each experimental group was superimposed to the digital master model, while for "precision" measurements all STL files of each experimental group were superimposed to each other., Results and Conclusions: The accuracy of full arch mandibular implant impressions was influenced both by the impression technique used (conventional vs. digital) and the impression material used (A-silicone vs. polyether) or the intraoral scanner used (Trios vs. Heron). In terms of "trueness," A-silicone showed the highest impression accuracy with the lowest deviation values, followed by polyether and Trios, but the differences between the three groups were in the majority not statistically significant. Heron showed statistically lower accuracy results in all measurements compared to the other groups. In terms of "precision", conventional impressions with the use of A-Silicone or polyether were statistically significantly superior to digital impressions with either scanner. A-Silicone and polyether showed no statistically significant difference between them., (© 2024 The Authors. Journal of Esthetic and Restorative Dentistry published by Wiley Periodicals LLC.)

Flabby ridge remained a challenge in dental clinical practice to obtain an accurate impression for edentulous patients. During the traditional impression making process, the excessive and displaceable soft tissue are usually compressed. In this article, we presented an impression method by using a modified special stock tray, impression compound and polyvinyl siloxane impression materials.•the suitable stock tray was modified with holes about 5 mm diameter in the corresponding area to the crest of the flabby ridge.•the primary impression was made by position the modified tray with the softened compound impression on the edentulous ridge, avoiding the area of the flabby ridge.•the final accurate impression was obtained by using the light body polyvinyl siloxane impression material., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

A common clinical condition affecting the alveolar ridges of the mandibular or maxillary arches is known as a "flabby ridge." This condition involves a superficial region of movable soft tissue. It is particularly prevalent among long-term denture users, especially in the lower anterior region. Flabby ridges occur when hyperplastic soft tissue replaces the alveolar bone, resulting in mobile, hypermobile, and frequently edematous tissue. This condition is most commonly found in the edentulous areas of the oral cavity, especially in the maxillary anterior region. To provide a good fit for the patient, it is necessary to create a denture with accurate morphology, unique contours, and mobility of flabby tissue. The presence of a flabby ridge can significantly impact the stability, fit, and functionality of dentures. Management of flabby tissue includes various methods such as impression techniques, surgical intervention, and denture designing. This case report aims to provide an improved and controlled application of polyvinyl siloxane impression material in managing flabby tissue conditions, which is commonly used in dental practices. It presents a modified window technique for making impressions of anterior mandibular flabby tissues with their natural, undistorted state, leading to a more accurate and stable denture fit., Competing Interests: Human subjects: Consent was obtained or waived by all participants in this study. Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work., (Copyright © 2024, Zilpilwar et al.)

Preliminary impressions must record the periphery and height of maxillary defects to allow for an eventual extension of the master impression tray. These impressions are usually made with irreversible hydrocolloid. Carrying the impression material into the defect can be complex, especially in the case of a limited oral opening. Moreover, the patient can be harmed during the removal procedure, and material may be stuck in anatomical structures. The technique presented in this article avoids these issues in any maxillary defect with a two-step preliminary impression. An elastomeric material ball is first placed in the defect until full setting. Then, this "obturator bulb" is removed and eventually relined until it is retentive. Retentions are designed on the oral side of the bulb and the bulb is placed back into the defect. Finally, an alginate over-impression of the maxillary is made. The alginate is removed after full setting, and the obturator can be reassembled on the maxillary impression to provide a full recording of the maxillary. This protocol can safely be used for defects of any size, despite eventual limitations in oral opening., (© 2023 by the American College of Prosthodontists.)

Purpose: To compare the quality of complete dentures and quality of life of participants rehabilitated by using TENS (Transcutaneous electric nerve stimulation) facilitated impression making with manual impressions., Material and Methods: Ten completely edentulous participants were enrolled in the crossover, pilot study. Participants were randomized in 2 groups. Five participants in each group were rehabilitated by dentures fabricated with TENS facilitated definitive impression technique (group T) and conventional impression technique (group C). In group T, Bioelectric border molding was done for the participants, that uses electric stimulation of the nerves supplying the muscles. In group C, incremental border molding using modeling plastic impression compound was carried out. Participants in each group used the dentures for 3 months. After 3 months, OHIP-EDENT questionnaire responses were obtained from the participants to observe the oral health related quality of life. A dental specialist recorded denture quality by Kapur scoring criteria. After one month wash period, the treatment was swapped between the groups. OHIP-EDENT scores and Kapur score were recorded for the alternate dentures after 3 months of use. Descriptive analysis was followed by Mann Whitney test to compare the overall scores between group T and group C for OHIP-EDENT, the scores for individual domains of OHIP-EDENT, and Kapur score for denture evaluation (α = 0.05)., Results: The overall OHIP-EDENT scores within each domain were less in group T when compared with the scores in group C and Kapur score for group T was more than group C. The difference was statistically significant i.e. P  = 0.002 & 0.003 respectively., Conclusions: Less OHIP-EDENT scores in group T imply better perception of quality of life of individuals due to better performance of stomatognathic system. The higher Kapur scores in group T signifies better quality of dentures when TENS was used for definitive impression making., (© 2024 The Authors. Published by Elsevier B.V. on behalf of Craniofacial Research Foundation.)

Objective To evaluate and compare the stability of the open tray impression coping within the set impression while attaching the lab analog when polyether (PE) heavy body and polyvinyl siloxane (PVS) putty impression materials were used and the implant platform was placed sub-gingivally at three different depths. Methods Two impression materials, PE and PVS, and custom-made plexiglass models with embedded single implants to simulate implant positioning depths of 0 mm, 2 mm, and 4 mm, sub-gingivally, were used in the study. Open tray impressions were made after attaching impression coping to the implant embedded in the model. Implant lab analog was attached to the impression coping in the set impression, and its stability was measured using a universal testing machine. Forty-two open tray impressions were made in six groups, with seven impressions in each group. Descriptive statistics such as mean and standard deviation were calculated. A comparison of the mean stability between the two impression materials at each depth was done using an independent t-test. Comparison of the mean stability between the three different subgingival implant depths in each material was done by one-way ANOVA with the Scheffe multiple comparison test (post-hoc analysis). The level of significance was set at p<0.05. Results The stability of the impression coping was measured as the force in Newtons required for the displacement of the analog attached to the impression coping embedded in the set impression. PE with the embedded impression coping at a depth of 0 mm gave the highest mean stability value (4.37+/-0.41), and the least mean stability was offered by PVS with the embedded impression coping at 4 mm depth (1.88+/-0.37). When an independent t-test was done to compare the mean stability values of PE and PVS, there was a statistically significant difference at 0 mm, 2 mm, and 4 mm. On doing one-way ANOVA to compare the mean stability between the different depth groups, there was a statistically significant difference between the three depth groups in PE and PVS. Scheffe multiple comparison tests (post-hoc analysis) revealed a statistically significant difference between 0 mm, 2 mm, and 4 mm subgingival depths of the impression coping placement in both PE and PVS. Conclusion The accuracy of the master cast is an important determinant for the precise fit and long life of the final prosthesis. In the case of maxillary anterior implant placements where deep subgingival placement of the implant platform is needed for aesthetic and functional reasons, the impression material should be selected carefully to ensure the stability of the impression coping. Among the materials included in the present study, the PE impression material offered the maximum stability for impression coping compared to PVS., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2024, P.M et al.)

Our research aims to investigate the impact mechanism of brand loyalty among gamers during the gaming process within the framework of brand loyalty theory and cognitive theory. We surveyed game players from Zhejiang Province, China. The research methods include a questionnaire survey and structural equation modelling. Results show that game experience, interaction, and impression are positively correlated with game trust, while game trust is positively correlated with game brand loyalty. Game trust, as a mediator variable, plays a complete mediation role. The clustering results of player gender and age as moderating effects are not significant. Based on the analysis results, we have suggested corresponding policy recommendations and reflections. Our research contributes to the analysation of impact mechanism of brand loyalty during the gaming process through the establishment of a structural equation model and provides suggestions and reflections on the development of the gaming industry., Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Zhao Xuanze reports financial support was provided by Zhejiang Cultural and Creative Industry Association., (© 2024 The Author(s).)

In every criminal inquiry, identification is of utmost importance. Cheiloscopy is a technique used in forensic investigation that focuses on identifying people from their lip prints. Just like fingerprints, each person's lip crease pattern is unique. Moreover, Lip prints are seen to remain consistent throughout an individual's life. Lip prints can therefore be used to confirm if a person was at the crime scene or not. Cheiloscopy is used to examine the sulci labiorum, or "lip prints," which are the wrinkling and furrows on the labial mucosa that produce a distinctive pattern. The current review article focuses on the potential of cheiloscopy as a vital role player in the process of criminal investigation by detecting and identifying individual(s)., (Copyright © 2023 Elsevier Masson SAS. All rights reserved.)

Exploring the generative capabilities of the multimodal GPT-4, our study uncovered significant differences between radiological assessments and automatic evaluation metrics for chest x-ray impression generation and revealed radiological bias., (©Sebastian Ziegelmayer, Alexander W Marka, Nicolas Lenhart, Nadja Nehls, Stefan Reischl, Felix Harder, Andreas Sauter, Marcus Makowski, Markus Graf, Joshua Gawlitza. Originally published in the Journal of Medical Internet Research (https://www.jmir.org), 22.12.2023.)

Purpose: Many elastomeric impressions sent to commercial laboratory dental technicians may include marginal defects. To fabricate accurate restorations, digital technology may be used to merge digital files of defective impressions into a single standard tessellation language (STL) file free of errors. This would save clinicians and patients time and may improve clinical care. The purpose of this study was to compare the accuracy of digital master casts reconstructed from merged STL files of defective impressions with the file of the original defect-free preparations., Material and Methods: Ivorine teeth on a dentoform were prepared to receive a posterior fixed dental prosthesis (FDP) with complete coverage preparations. An impression was made in a stock tray using polyvinyl siloxane (PVS) impression material and an extraoral scanner (E3, 3Shape, Denmark) was used to digitize the impression; this was the reference cast. Wax was used to create defects on the buccal and lingual margins of the preparations. Fifteen PVS impressions were made of the FDP preparations with defects in the mesial and distal margins; another set of 15 PVS impressions was made of FDP preparations with defects in the buccal and palatal margins for a total of 30 impressions. All impressions were digitized using the same extraoral scanner (E3, 3Shape, Denmark). Corresponding STL files were paired and merged, and a master cast was created by eliminating the defects using the scanned data. This master cast was compared to the reference cast using reverse engineering software (Geomagic, Morrisville, NC, USA). The results were expressed as average errors and standard deviations in the master casts relative to the reference cast. To account for the presence of positive and negative values in the data set, in terms of errors, the root mean square (RMS) value was calculated for each sample., Results: The mean average error in the sample was -0.4 μm. The average upper limit of 95% confidence interval was +36.5 μm, while the average lower limit of 95% confidence interval was -37.3 μm. The mean RMS of the errors found was 18.9 μm., Conclusions: The results of this study indicated that merging digitized definitive impressions to correct marginal defects resulted in master casts with a high level of accuracy relative to the reference cast., (© 2023 by the American College of Prosthodontists.)

Purpose: This systematic review aimed to investigate the accuracy of intraoral scan (IOS) impressions of implant-supported restorations in in vivo studies., Methods: A systematic electronic search and review of studies on the accuracy of IOS implant impressions were conducted to analyze the peer-reviewed literature published between 1989 and August 2023. The bias analysis was performed by two reviewers. Data on the study characteristics, accuracy outcomes, and related variables were extracted. A meta-analysis of randomized control trials was performed to investigate the impact of IOS on peri-implant crestal bone loss and the time involved in the impression procedure., Results: Ten in vivo studies were included in this systematic review for final analysis. Six studies investigated the trueness of IOS impressions, but did not reach the same conclusions. One study assessed the precision of IOS impressions for a single implant. Four clinical studies examined the accuracy of IOS implant impressions with a follow-up of 1-2 years. In full arches, IOS impression procedure needed significantly less time than conventional one (mean difference for procedure time was 8.59 min [6.78, 10.40 min], P < 0.001), prosthetic survival rate was 100%, and marginal bone levels of all participants could be stably maintained (mean difference in marginal bone loss at 12 months was 0.03 mm [-0.08, 0.14 mm], P = 0.55)., Conclusions: The accuracy of IOS impressions of implant-supported restorations varied greatly depending on the scanning strategy. The trueness and precision of IOS in the partial and complete arches remain unclear and require further assessment. Based on follow-up clinical studies, IOS impressions were accurate in clinical practice. However, these results should be interpreted with caution, as some evidences are obtained from the same research group., (© 2023. The Author(s).)

People often form immediate expectations about other people, or groups of people, based on visual appearance and characteristics of their voice and speech. These stereotypes, often inaccurate or overgeneralized, may translate to robots that carry human-like qualities. This study aims to explore if nationality-based preconceptions regarding appearance and accents can be found in people's perception of a virtual and a physical social robot. In an online survey with 80 subjects evaluating different first-language-influenced accents of English and nationality-influenced human-like faces for a virtual robot, we find that accents, in particular, lead to preconceptions on perceived competence and likeability that correspond to previous findings in social science research. In a physical interaction study with 74 participants, we then studied if the perception of competence and likeability is similar after interacting with a robot portraying one of four different nationality representations from the online survey. We find that preconceptions on national stereotypes that appeared in the online survey vanish or are overshadowed by factors related to general interaction quality. We do, however, find some effects of the robot's stereotypical alignment with the subject group, with Swedish subjects (the majority group in this study) rating the Swedish-accented robot as less competent than the international group, but, on the other hand, recalling more facts from the Swedish robot's presentation than the international group does. In an extension in which the physical robot was replaced by a virtual robot interacting in the same scenario online, we further found the same results that preconceptions are of less importance after actual interactions, hence demonstrating that the differences in the ratings of the robot between the online survey and the interaction is not due to the interaction medium. We hence conclude that attitudes towards stereotypical national representations in HRI have a weak effect, at least for the user group included in this study (primarily educated young students in an international setting)., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Cumbal, Axelsson, Mehta and Engwall.)

Purpose: To compare the marginal accuracy of zirconia crowns fabricated by different workflows (conventional and digital) and designs (monolithic and veneered)., Materials and Methods: A prepared maxillary first molar was used for the study. Four workflow combinations were evaluated: (1) intraoral scanning and monolithic zirconia (IOS-M), (2) intraoral scanning and veneered zirconia (IOS-V), (3) conventional impression and monolithic zirconia (IMP-M), and (4) conventional impression and veneered zirconia (IMP-V). All of the specimens had similar designs. The veneered groups had a buccal cutback for esthetic veneer application. A total of 10 crowns were produced in each workflow. The vertical and horizontal marginal accuracies were measured with a traveling microscope. Depending on the normality of the data, one-way analysis of variance test or Kruskal-Wallis test were applied to evaluate the differences among the groups (α = 0.05)., Results: The most superior vertical marginal accuracy was observed for IOS-V (mean = 22.5 μm; SD = 6.7 μm), followed by IMP-V (mean = 23.9 μm; SD = 7.8 μm), IOS-M (mean = 28.7 μm; SD = 10.3 μm), and IMP-M (mean = 39.8 μm; SD = 22.0 μm), respectively (p < 0.001). The IOS-M had the greatest mean horizontal discrepancies (mean = 23.9 μm; SD = 4.3 μm) followed by IMP-M (mean = 21.3 μm; SD = 5.7 μm), IMP-V (mean = 19.2 μm; SD = 5.3 μm) and IOS-V (mean = 17.6 μm; SD = 5.7 μm) (p < 0.001)., Conclusions: Monolithic zirconia crowns fabricated digitally had superior marginal accuracy than monolithic zirconia crowns fabricated conventionally. Esthetic buccal veneering of predominantly monolithic zirconia copings improved the vertical and horizontal marginal accuracies., (© 2022 The Authors. Journal of Prosthodontics published by Wiley Periodicals LLC on behalf of American College of Prosthodontists.)

Humans exhibit colour vision variations due to genetic polymorphisms, with trichromacy being the most common, while some people are classified as dichromats. Whether genetic differences in colour vision affect the way of viewing complex images remains unknown. Here, we investigated how people with different colour vision focused their gaze on aesthetic paintings by eye-tracking while freely viewing digital rendering of paintings and assessed individual impressions through a decomposition analysis of adjective ratings for the images. Gaze-concentrated areas among trichromats were more highly correlated than those among dichromats. However, compared with the brief dichromatic experience with the simulated images, there was little effect of innate colour vision differences on impressions. These results indicate that chromatic information is instructive as a cue for guiding attention, whereas the impression of each person is generated according to their own sensory experience and normalized through one's own colour space.

The assessment of rehabilitation outcomes requires a patient documentation protocol, including records obtained at standardized ages, to compare different types of surgeries, their effects, as well as between different rehabilitation centers. The aim of this paper was to present proper trays for babies with different types of cleft lip and palate, which are used in the outpatient routine at Hospital of Rehabilitation of Craniofacial Anomalies/USP (HRAC/USP). The customized trays are made with self-curing acrylic resin. The tray must have suitable depth to copy the buccal sulcus, and wax is usually applied to contour the tray edge, and the adjustment of the tray to the fornix, making the tray specific for each child. The impression precludes the utilization of dental casts for diagnosis, treatment plan, and research measurements. In the clinical practice at HRAC-USP, it was observed that customized trays increased the quality of impression, accurately reproducing anatomical features of dental arches of babies with oral clefts.

Introduction: An implant-supported prosthesis requires a precise imprint to provide a good fit. It has been suggested that for implant/abutment level impressions, both the indirect (closed tray) and direct (open tray) methods are effective in achieving a passively fitting prosthesis., Aim: With an open plate embed level impression technique, this in vitro investigation set out to evaluate three different elastomeric imprint materials for their relative rigidity and precision., Materials and Methods: Sixty bespoke trays were created. Part I (rotational opposition assessment) of the investigation included selecting 30 uniquely shaped plates at random and using them to create embed-level open plate engraves. The second part of this investigation (evaluation of rotational discrepancy and vertical inconsistency) used open plate embed level impressions generated with the remaining thirty individualized plates to evaluate how well these materials recreated the patient's impressions., Result: Within the bounds of the current investigation, vinylpolysiloxane had the highest degree of stiffness among the impression materials examined in comparison to polyether and vinylsiloxanether, as seen by its much greater rotational resistance to torquing. A rotational discrepancy was shown to be much lower in polyether open tray implant level impressions compared to vinylpolysiloxane and comparable to vinylsiloxane., Conclusion: In this investigation, the firmest impression medium was vinylpolysiloxane, followed by polyether and vinylsiloxanether for taking imprints of implants. Polyether material, however, was more precise than vinylpolysiloxane and vinylsiloxanether., Competing Interests: There are no conflicts of interest., (Copyright: © 2023 Journal of Pharmacy and Bioallied Sciences.)

The design of the light environment plays a critical role in the interaction between people and visual objects in space. Adjusting the space's light environment to regulate emotional experience is more practical for the observers under lighting conditions. Although lighting plays a vital role in spatial design, the effects of colored lights on individuals' emotional experiences are still unclear. This study combined physiological signal (galvanic skin response (GSR) and electrocardiography (ECG)) measurements and subjective assessments to detect the changes in the mood states of observers under four sets of lighting conditions (green, blue, red, and yellow). At the same time, two sets of abstract and realistic images were designed to discuss the relationship between light and visual objects and their influence on individuals' impressions. The results showed that different light colors significantly affected mood, with red light having the most substantial emotional arousal, then blue and green. In addition, GSR and ECG measurements were significantly correlated with impressions evaluation results of interest, comprehension, imagination, and feelings in subjective evaluation. Therefore, this study explores the feasibility of combining the measurement of GSR and ECG signals with subjective evaluations as an experimental method of light, mood, and impressions, which provided empirical evidence for regulating individuals' emotional experiences.

This study aimed to examine the effect of inter-dental abutment distance on the accuracy of digital and conventional impression methods. Five maxillary and mandibular models were prepared with different inter-dental abutment distances. Digital scans were obtained using an extraoral laboratory scanner as reference data. Each group was scanned 8 times using the intra-oral scanner for the digital method. For the conventional impression method, 8 additional silicone impression material was used to generate the stone casts from each group. Then casts were scanned. In the next step, stereolithography (STL) data was exported from the scans. The STL files were super-imposed on the reference scans using 3shape dental designer software to make the measurement. Kolmogorov-Smirnoff was used to determine if the data were normally distributed. In the digital impression method, as the abutment distance increased, the accuracy decreased. Various inter-dental abutment distances in digital groups showed significant differences (p=0.016) in impression accuracy, while the difference among conventional groups was not statistically significant (p=0.822). In the digital method, the mean inter-dental abutment between the 4-5 and 3-7 groups, 4-6 and 3-7 groups had a significant difference (p<0.05). However, the conventional method revealed no significant differences (p>0.05) between groups. In conclusion, when the inter-dental abutment distance exists and is surrounded by soft tissue, the possibility of error in the digital impression method is higher than in the conventional impression method., Competing Interests: The authors declare no conflict of interest., (©2023 JOURNAL of MEDICINE and LIFE.)

Background: Recording accurate impressions from maxillary defects is a critical and challenging stage in the prosthetic rehabilitation of patients following maxillectomy surgery. The aim of this study was to develop and optimize conventional and 3D-printed laboratory models of maxillary defects and to compare conventional and digital impression techniques using these models., Methods: Six different types of maxillary defect models were fabricated. A central palatal defect model was used to compare conventional silicon impressions with digital intra-oral scanning in terms of dimensional accuracy and total time taken to record the defect and produce a laboratory analogue., Results: Digital workflow produced different results than the conventional technique in terms of defect size measurements which were statistically significant ( p < 0.05). The time taken to record the arch and the defect using an intra-oral scanner was significantly less compared with the traditional impression method. However, there was no statistically significant difference between the two techniques in terms of the total time taken to fabricate a maxillary central defect model ( p > 0.05)., Conclusions: The laboratory models of different maxillary defects developed in this study have the potential to be used to compare conventional and digital workflow in prosthetic treatment procedures.

A dimensionally accurate impression is one of the primary determinants for the precise fabrication of complete denture prostheses in microstomia patients. This can be achieved with the help of sectional trays. This technical report describes the fabrication of a sectional impression tray with a reusable sectional handle using magnets. The handles can be sterilized and reused, thus saving clinical time for future use. The proposed method provides ease of reassembling and disassembling, easy placement, and guided orientation of the two tray segments., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2023, Colvenkar et al.)

Gagging poses a clinical difficulty to the dentist in all facets of therapy, from diagnostic techniques to active treatment. Various treatment methods to manage the gagging include behavioral techniques, acupressure, acupuncture, hypnosis, systemic desensitization, and pharmacological techniques. This article presents a straightforward method for getting rid of the gag reflex using an eye massager. Eye massagers can help reduce the stress and anxiety associated with dental procedures by providing an effective alternative to traditional methods. This technique can be a valuable aid in making short dental procedures more comfortable and successful., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2023, Colvenkar et al.)

Objectives: Anatomical variations of the sacrum involve alterations in the number of sacral segments, auricular surface area, and neural arch dimensions and are associated with biomechanical, surgical, and obstetric implications. Due to the complex functional structure of the sacroiliac (SI) joints, it was aimed to evaluate their morphometric structure, classify the sacrum, and group different locations of the auricular surface in the sacrums., Methods: Sex determination was made in 91 dry human sacra. Determination of the alpha angle on the sagittal axis of the auricular surface of the sacrum and classification of the auricular surface of the sacrum was performed. The sacra were studied to determine the position and extent of their auricular surfaces in relation to the sacral segments. Specimens were grouped as "normal," "high-up," and "low-down" auricular surface-bearing sacra. The sacral surface areas were measured, and SI joints were classified into three types morphologically (types I, II, and III). The depth and anterior-posterior length of the cranial, middle, and caudal impressions observed in the posterior sacrum and anterior-posterior lengths were measured., Results: The measurements made for sex determination showed that 46 of the sacra were from females and 45 were from males. The alpha angle on the sagittal axis of the sacral auricular surface was found to be greatest at the level of the first posterior sacral foramina. While the most common sacrum type was Type III, the least common type was Type I. The surface area of facies auricularis was found to be larger in males than in females. With regard to facies auricularis in all sacrum groups, although it covered approximately 2.5 sacral vertebrae, there was a difference in the location of facies auricularis in the sacral vertebrae. A statistically significant difference was found between right and left in the depth values of the impressions in the dorsal surface of the sacrum (p <0.05)., Conclusion: The position of the auricular surface in the sacrum differed among individuals. These differences are associated with variable load-bearing in the SI joints. The biomechanical classification of the sacrum and localization of the auricular surface can provide information about the anatomic source of low back pain or help predict the location of low back pain. Changes in the synovial surface morphology of the SI joints may elicit sacroiliac joint pain. This study was conducted because it is considered that the location of the auricular surface can significantly affect load-bearing patterns of the sacrum., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2023, Cihan et al.)

Objectives: To evaluate an in situ reference acquisition method for implant positions in complete edentulous maxillae using an industrial scanner and allowing for in vivo trueness analysis of the restorative workflow. To assess in vivo trueness and precision of intraoral scanners (IOS) using different acquisition protocols. Furthermore, to compare IOS trueness with impression-based models and implant-supported fixed dentures (IFD) in a parallel study on the same cohort using the same in situ reference scan., Methods: Six scan-bodies mounted to maxillary implants in five subjects were reference scanned (REF) using an industrial scanner. Subjects were scanned with IOS three times using three different protocols: control (CT), dental floss assisted (DF), and acrylic splint (SP). CAD-files of scan-bodies with inter-aligned analogues were geometry-aligned to REF, and SP. Scan-bodies were aligned to CT and DF in proprietary dental laboratory software and exported with analogue positions. Resulting six CAD-analogues per scan were Globally Aligned using a consistent geometry-based alignment. Deviations were computed after a Reference Point System Alignment at the implant/prosthetic platform for Cartesian axes with a linear Resultant., Results: Resultant trueness was CT: 41±11 µm, DF: 49±22 µm, SP: 55±8 µm. Resultant precision was CT: 48±7 µm, DF: 50±7 µm, SP: 45±6 µm., Conclusions: This method is applicable for assessing trueness of maxillary full-arch implant scans in vivo. The CT protocol was most accurate. CT trueness showed no difference to digitised impression-based models in parallel study. CT was more accurate than IFD in a parallel study. CT displayed similar numerical trueness as existing in vitro studies., Clinical Significance: Using IOS to acquire full-arch implant scans is controversial. The modified protocol in this pilot shows promising results in the maxilla where great care was taken to manage non-attached tissues when a modified scanning pattern was used. However, other IOS may show varying results in vivo. A completed scan does not necessarily equate to an accurate scan., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022. Published by Elsevier Ltd.)

Recently, many studies have indicated that humans make social evaluations from facial appearances instantaneously and automatically. Furthermore, such judgments play an important role in several social contexts. However, the mechanisms involved in the ability to form impressions from faces are still unknown, as is the extent to which these can be regarded as universal in perceiving impressions. In the current study, computer-generated Caucasian faces were used to assess the universality or cultural differences in impression formation among Japanese children and adults. This study hypothesized that impressions of trustworthiness and dominance may be more fundamental and universal, whereas the impression of competence may be more complex and culture-dependent. In Experiment 1a, 42 children aged 3-6 years were presented with 10 pairs of face images and asked which image in each pair was more trustworthy, dominant, or competent. Overall, it was found that as age increased, the rate of agreement of Japanese participants with the judgment of American participants, obtained in a previous study, increased. However, the agreement rate for competence was relatively low. Experiment 1b, conducted with 46 children, was a replication of Experiment 1a, and the results showed the same tendency. In Experiment 2, 45 Japanese adults made impression judgments on 19 pairs of face images identical to those used in Experiment 1b. The results suggested that while dominance was a dimension not easily influenced by developmental changes or culture, trustworthiness could be influenced by cultural differences in facial expression recognition. Therefore, different judgment criteria are used for children and adults. For competence, the agreement rate with Americans was relatively stable and low among the different age groups. This suggests that depending on the dimension of the trait, certain judgments are influenced by cultural context and, therefore, change criteria, while others are based on more universal criteria., Competing Interests: The author declares that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Sakuta.)

Microstomia presents a unique challenge to the dentist as well as the patient. Microstomia patients often face difficulty in inserting or removing removable dental prostheses due to constricted opening of the oral cavity. Dentists often face difficulty in inserting impression trays in these patients because of the limited mouth opening. Standard impression procedures need to be modified in such patients. This article describes a simple design for the fabrication of a sectional handle for a definitive impression in microstomia patients. The sectional handle could be sterilized and reused., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2022, Kunusoth et al.)

Arthropod predators are abundant in turfgrass systems, and they play an important role in managing pests. Understanding the vertical distribution of predation is critical to developing cultural strategies that enhance and conserve predatory services. However, little is known on how the predation is vertically distributed within the turfgrass canopy. Thus, the objective of this study was to determine the vertical distribution of predation within the turfgrass canopy. Clay models were used to emulate the general appearance of Noctuidae caterpillars, to estimate the predatory activity. The choice and no-choice experiments were conducted by placing clay models at 2.54, 5.08, and 7.62 cm from the thatch surface and denoted as lower, intermediate, and upper levels, respectively, within turfgrass canopy. The predator-mediated impressions, paired mark, scratch, deep cut mark, deep distortion, prick, dent, stacked surface impression, scooped mark, granulation, and U-shaped mark, were identified on clay models. The incidence and severity of impressions were significantly greater on clay models placed at the lower canopy level than on those placed at the intermediate and upper canopy levels in the choice and no-choice experiments (P < 0.05). Thus, predators are more likely to find their prey at the soil level. This information can be used to refine management strategies, such as mowing height and insecticide use for effectively managing soil-borne and foliar-feeding arthropod pests and beneficial arthropods., (© The Author(s) 2022. Published by Oxford University Press on behalf of Entomological Society of America.)

Many studies demonstrate that people form their first impression of a stranger based on facial appearance, and these impressions influence their subsequent decisions and behaviors. However, much less research has examined the factors that moderate the accuracy of first impressions based on a photo of face. The present study included three experiments to explore gender differences in the accuracy of impressions based on faces. The results showed that people judge facial attractiveness more accurately for female faces than for male faces while giving more accurate wealth judgments for male faces than for female faces. Interestingly, although we did not find a significant correlation between confidence ratings and the accuracy of wealth rating, we recognized a significant moderate correlation between confidence ratings and the accuracy of attractiveness ratings when female participants rated male faces. To our knowledge, the present study is the first to reveal gender biases in the accuracy of impression judgments based on facial appearance. These findings imply a significant influence of traditional gender roles on accurate facial judgments., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Qi and Ying.)

Background: Advertising alcoholic drinks and food high in fat, sugar, and salt (HFSS) is a driver of alcohol use and HFSS consumption, among children and young people. Whilst advertising legislation and broadcasting regulation protect children from alcohol and HFSS imagery, the 2018 FIFA World Cup, which attracted a global audience, was sponsored and partnered by alcohol and HFSS brands. This study investigated the exposure of viewers to HFSS and alcohol imagery in a selection of group matches, and the final match, of the FIFA 2018 World Cup., Methods: The frequency and duration of appearances (to the nearest second) of branding from two sponsors (McDonald's and Budweiser), one official partner (Coca-Cola) and the official sports drink (Powerade) were recorded during all active play in live coverage of a sample of 13 matches (Six in Group A, which included the host nation, Russia, which has stringent alcohol promotion regulations in place; six in Group G, which featured England; and the final) broadcast in the UK. We used census and viewing data to calculate gross and per capita impressions generated by this imagery in the UK population., Results: The 13 matches included 1262 min of active play and a total of 1806 appearances of alcohol and HFSS food advertisements, delivering approximately 7.5 billion branded HFSS impressions, including 759 million to children (age < 16 years), and 3.3 billion alcohol impressions, including 385 million to children, in the UK. Appearances of HFSS and alcohol brands were not statistically different between the games in either group., Conclusion: UK advertising legislation and broadcasting regulations intended to prevent exposure to alcohol and HFSS imagery and advertising in UK television was circumvented completely by sponsorship arrangements in the 2018 FIFA World Cup. Preventing this exposure therefore requires revision of existing advertising and broadcasting controls to include sponsorship., (© 2022. The Author(s).)

To compare the three-dimensional accuracy of an open-tray and two snap on impression techniques (with and without connecting the plastic caps of the snap on impression transfers) in a full arch 6-implant model, a reference acrylic resin model of the maxilla with six implants was fabricated. Prominent geometrical triangles, in the palate area, served as reference points for a digital overlap between scans. Three impression transfer techniques were evaluated and compared: open-tray direct impression (DI), snap on impression (SpO), and connected snap on impression (SpOC). Polyether impression material was used to make 30 impressions (n = 10), and the master model and all casts were digitally scanned with a laboratory optical scanner. The obtained 3D data were converted and recorded as STL files, which were imported to a 3D inspection software program. Angular deviations (buccal, occlusal and interproximal planes) between the study casts and the reference model were measured. Data were analyzed using one-way analysis of variance (ANOVA) and Tukey post hoc test, with 0.05 used as the level of significance. The 3D angular deviations from the master model revealed no significant differences between the DI and SpO impression groups, but there were significant differences in the SpOC impression group, particularly in the buccal and occlusal planes. In all groups, the 3D angular deviation between the most distal scan abutments on each side of the model was significantly different from all other areas when compared to the master model. Within the limits of this study, it is possible to conclude that the indirect closed tray snap on impression technique with unconnected plastic caps exhibited the same three-dimensional accuracies as the direct open tray technique. The indirect closed tray snap on impression technique with connected plastic caps was less accurate than either the indirect closed tray snap on impression technique with unconnected plastic caps or the direct open tray technique. In the case of full arch implant supported prostheses, inaccuracies may be expected in the most distal implants for all the three impression techniques evaluated in this study. Further in vitro and in vivo research is required.

A digital technique is described for designing and fabricating segmental individual tooth trays that can be used to make an impression of multiple preparations with high accuracy and efficiency. A digital model of prepared dentition was acquired. The segmental individual tooth trays with retention attachments and tissue stops were designed and 3D printed with light-polymerizing resin. The segmental impression of each section of the prepared dentition was made with the corresponding individual tooth tray loaded with the impression material. A final overall impression was made to pick up the segmental individual tooth trays with a full arch tray., (© 2021 by the American College of Prosthodontists.)

Purpose: This study comprehensively reviewed the current status of digital workflows in fabricating removable partial dentures (RPDs) using evidence from clinical trials and case reports., Study Selection: We performed a systematic review of the literature on the materials and fabrication of RPDs using digital technologies published in online databases from 1980 to 2020. We selected eligible articles from the search results, retrieved information on digital RPDs from these, and conducted a qualitative analysis. We report evidence from clinical papers and case reports, digital impression-taking methods, and maxillomandibular relationship (MMR) records., Results: A case report electronically published in 2019 introduced a clasp-retained RPD fabricated via a full-digital workflow without a gypsum definitive cast. Computer-aided design and computer-aided manufacturing of double-crown-retained RPDs with nonmetal materials were described in some case reports. Intraoral scanners were used to obtain digital impressions and MMR records in the fabrication of digital RPDs, which have potential advantages for reducing the number of clinical appointments and simplifying laboratory procedures. Evidence from clinical trials is scarce; a randomized controlled trial reported higher patient satisfaction with digital clasp-retained RPDs than with conventional RPDs., Conclusions: Full-digital RPDs can be fabricated without a gypsum definitive cast. However, the indication for full-digital RPDs is limited to cases with Kennedy Class III/IV partially edentulous arches with several missing teeth. Challenges in digital impression-taking and MMR recording remain to be solved to extend these indications. More evidence from clinical trials is required to evaluate the efficacy and usefulness of digital RPDs.

The present study investigated the pre-impressions of medical staff toward coronavirus disease 2019 (COVID-19) vaccination in a designated medical institution for class II infectious diseases in Sakaide, Japan using a text mining analysis. A total of 387 medical staff were surveyed on their pre-vaccination impressions toward the COVID-19 vaccine using an open-ended questionnaire from March 1st to 7th (the first survey) and from March 22nd to 28th (the second survey) at Sakaide City Hospital, Sakaide, Japan. A total of 296 people answered the question for the first time and 234 people answered for the second time among the 387 people. The vaccination rate was slightly lower for the younger generation than for the older generation. Before the first vaccination, the younger generation expressed concerns about side effects as well as a negative impact on pregnancy. However, before the second vaccination, there were fewer concerns regarding side effects and words of reassurance were also noted. Nurses expressed more opinions about side effects in both the first and second vaccinations than other medical staff. Concerns regarding side effects among medical staff decreased with the progression of COVID-19 vaccination. These data may provide useful information about the promotion of COVID-19 vaccination to the public, particularly in the young generation and women.

A digital technique for designing and fabricating an individual tooth tray used for taking subgingival impression of complete crown preparation was described. The digital model of required dentition region was obtained before performing crown preparation. An individual tooth tray with retention attachments was designed and printed with plastic material. After conducting crown preparation, the individual tooth tray loaded with the final impression material was placed onto the abutment to deliver the impression material subgingivally. A final overall impression was made with full arch stock tray to pick up the individual tooth tray with the accurate impression of abutment., Competing Interests: The authors have no conflicts of interest relevant to this article., (© 2021 Association for Dental Sciences of the Republic of China. Publishing services by Elsevier B.V.)

Purpose: To investigate the effect of impression technique (conventional preliminary alginate and digital scan) and operator experience in impression making (experienced in digital and conventional, experienced in conventional and inexperienced in digital, and inexperienced in conventional and digital) on impression time, satisfaction and stress levels, and the preference of the operators., Material and Methods: One patient was assigned for each of the 60 operators, who were experienced in impression techniques at different levels (Group 1: experienced in conventional and digital, Group 2: experienced in conventional and inexperienced in digital, Group 3: inexperienced in conventional and digital). They made conventional impressions (irreversible hydrocolloid) and digital scans (Trios 3) from the same patient. The impression times were recorded at each step (patient registration, maxillary arch, mandibular arch, and bite registration) and in total. A visual analog scale (VAS) was used for the operator satisfaction for applicability, comfort, and hygiene; the State-Trait Anxiety Inventory form (STAI-TX1) was used for stress, and a questionnaire was completed to measure the operator's impression preference. The data were analyzed with a 2-way ANOVA and Chi-square test (α = 0.05)., Results: A significant interaction was found between the operator experience in impression making and the impression technique on time for maxillary and mandibular arch impressions and total time (p ≤ 0.002). Operator experience and impression technique interaction had a significant effect on comfort and average VAS scores (p ≤ 0.016). Whereas, no significant effect of this interaction was found on stress (p ≥ 0.195). Operator experience in impression making had a significant effect on applicability (p < 0.001), and the impression technique had a significant effect on hygiene VAS scores (p < 0.001). Operators in Group 1 and Group 3 preferred the digital scans, however, operators in Group 2 had no preference (p = 0.022)., Conclusion: Operator experience in impression making and impression technique had varying effects on clinician's impression time, comfort, applicability, hygiene, and preference. Operators needed less time for the impressions they were experienced with. Operator stress level was not affected by the operator experience in impression making and the impression technique. Dental students and operators experienced in both techniques were satisfied with the digital scans and they preferred digital scans. Operators experienced with conventional impressions were satisfied with conventional impressions but didn't have a preference for the impression type., (© 2021 by the American College of Prosthodontists.)

Online experimental methods are used in psychological studies investigating the perceptions and impressions of facial photographs, even without substantial evidence supporting their reliability and validity. Although, the quality of visual stimuli is more difficult to control remotely, the methods might allow us to obtain a large amount of data. Then the statistical analysis of a larger volume of data may reduce errors and suggest significant difference in the stimuli. Therefore, we analyzed the reliability and validity of online surveys in investigating the perceptions (shine, red, and dark) and impressions (attractiveness, trustworthy, and so on) of facial photographs created from averaged faces with skin tones modified using computer graphics (CG). In this study, we conducted online (Online1) and laboratory experiments with well-controlled conditions (Control). For each experiment, 50 participants (men and women in Japan, age: 20-59years) completed the same questionnaire regarding their impressions of the same 28 CG facial photographs. The results showed significant correlations between the two experiments for all 19 items in the questionnaire. SD in the Online1 compared to the Control from the stimuli and individual differences were 56-84 and 88-104% in each questionnaire items, respectively. Moreover, the rates of mismatching perceptual evaluations to the corresponding physical features demonstrated in the photographs were 4.9-9.7% on average in an additional online survey of another 2,000 participants (Online2). These results suggest that online surveys can be applied to experiments to investigate impressions from CG facial photographs instead of general laboratory experiment by obtaining an appropriate number of participants to offset larger statistical errors that may result from the increased noise in the data from conducting the experiment online., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Hirao, Koizumi, Ikeda and Ohira.)

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.

Objectives: The present study aimed to investigate whether there are differences between Arabic-speaking and Finnish-speaking listeners in the impressions of a speaker's personality as evoked by various intentional voice qualities., Study Design: This is an experimental study., Methods: Samples (N = 55) were gathered from native Finnish-speaking males (N = 4) and females (N = 5), who read a text passage of 43 words using eight different voice qualities: (1) habitual speaking voice, speaking with (2) a forward or (3) backward placement of the tongue, or a (4) breathy, (5) tense, (6) creaky, (7) nasalized, or (8) denasalized voice. Native Arabic-speaking participants (34 males, 12 females; N = 46) were asked to evaluate the speech samples on a seven-point polarized scale by choosing 1-5 from a total of 18 contrasting pairs of personality traits. The listening tests were presented via Windows Media Player and a Genelec Biamp loudspeaker. Traits that had evaluations of 30% or more were selected for the final analysis. The results were compared to the results of native Finnish-speaking listeners (12 males, 38 females; N = 50). Statistical analyses were carried out using IBM SPSS Statistics 25., Results: On the whole, both listener groups perceived the speakers' voice qualities similarly, although the Finnish-speaking listeners linked many voice qualities, especially nasal and denasal voices, with unpleasant and other negative personality traits. Moreover, somewhat opposing evaluations were given by the two language groups for voices with forward and backward placements of the tongue, and breathy and tense voices. In many cases, the evaluations by the Arabic-speaking listeners were more scattered. The speakers' sex also seemed to affect perceptions of personality., Conclusions: There seem to be similar stereotypical tendencies to relate certain voice qualities with certain personality traits, which is explainable by how the voice types are produced and used to express emotions. Some opposing trends found between the two language groups may be related to language and cultural differences. A further study with larger listener groups and including also samples from Arabic language speakers is needed to confirm the results of the present study., (Copyright © 2019 The Voice Foundation. Published by Elsevier Inc. All rights reserved.)

Background: In the production of ankle-foot orthoses and in-shoe foot orthoses, lower leg morphology is traditionally captured using a plaster cast or foam impression box. Plaster-based processes are a time-consuming and labour-intensive fabrication method. 3D scanning is a promising alternative, however how these new technologies compare with traditional methods is unclear. The aim of this systematic review was to compare the speed, accuracy and reliability of 3D scanning with traditional methods of capturing foot and ankle morphology for fabricating orthoses., Methods: PRISMA guidelines were followed and electronic databases were searched to March 2020 using keywords related to 3D scanning technologies and traditional foot and ankle morphology capture methods. Studies of any design from healthy or clinical populations of any age and gender were eligible for inclusion. Studies must have compared 3D scanning to another form of capturing morphology of the foot and/or ankle. Data relating to speed, accuracy and reliability as well as study design, 3D scanner specifications and comparative capture techniques were extracted by two authors (M.F. and Z.W.). Study quality was assessed using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) and Consensus-Based Standards for the Selection of Health Measurement Instruments (COSMIN)., Results: Six articles met the inclusion criteria, whereby 3D scanning was compared to five traditional methods (plaster cast, foam impression box, ink footprint, digital footprint and clinical assessment). The quality of study outcomes was rated low to moderate (GRADE) and doubtful to adequate (COSMIN). Compared to traditional methods, 3D scanning appeared to be faster than casting (2 to 11 min vs 11 to 16 min). Inter-rater reliability (ICC 0.18-0.99) and intra-rater reliability (ICCs 0.25-0.99) were highly variable for both 3D scanning and traditional techniques, with higher agreement generally dependent on the foot parameter measured., Conclusions: The quality and quantity of literature comparing the speed, accuracy and reliability of 3D scanning with traditional methods of capturing foot and ankle morphology is low. 3D scanning appears to be faster especially for experienced users, however accuracy and reliability between methods is variable.

Objective: To provide the basis for the clinical development of ultrasonic shoulder preparation by comparing the roughness and three-dimensional topography of shoulder surface between ultrasonic instruments and conventional rotary instruments, to make preliminary suggestions for clinical use of ultrasonic instruments., Methods: (1) Four areas of buccal and palatal surfaces of six extracted human premolars were prepared with different grit size of rotary instruments. Polyether was used to take impression of the shoulder area, 3-D topography measurement laser microscope (3-D TMLM) was used to scan the impressions and compare the shoulder surface roughness of the four areas. (2) Six extracted human premolars were prepared, mesial half of the shoulder was finished with traditional rotary instruments and distal half with ultrasonic instruments. Polyether was used to take impression of the shoulder area, 3-D TMLM was used to scan the impressions and compare the shoulder surface roughness and 3-D topography, and the shoulder surface morphology was observed by surgical microscope (×25 magnification). (3) Twenty extracted human maxillary symmetrical homonymous anterior teeth were poured into die stone using artificial gingiva, ultrasonic instruments group and rotary instruments group were divided randomly. After preparing the teeth and taking the shoulder impression with polyether in dental simulate on the training system, the surface roughness of the shoulder impression in mesial, middle and distal areas was scanned and compared. The data were analyzed using SPSS 25.0 software package., Results: (1) There was no significant difference in Ra and Rz values between the abutment shoulder and impression shoulder in different areas. (2) The surface roughness of the shoulder impression prepared by ultrasonic instruments [Ra:(6.59±2.33) μm, Rz:(34.69±7.29) μm] was significantly smaller than that of the rotary instruments [Ra:(21.79±4.89) μm, Rz:(91.69±14.82) μm] ( P < 0.05). The morphology of the shoulder prepared by ultrasonic instruments was clear and continuous under microscope observation. (3) The surface roughness of each area of the shoulder prepared by ultrasonic instruments was significantly lower than that of the rotary instruments ( P < 0.001); there was no significant difference of the surface roughness (Ra) in each area of the shoulder impression after ultrasonic instrument preparation, while the shoulder impression roughness in the mesial and distal areas was significantly higher than that in the middle area ( P < 0.001) after rotary instrument preparation., Conclusion: Compared with the rotary instruments, the ultrasonic instruments can obtain a smoother shoulder surface, especially can significantly improve the shoulder preparation effect near the proximal surface.

Background: Recently, a study revealed that people liked others significantly more than they estimated that others liked them. Thus, the study found that people tended to underestimate how much others liked them, a phenomenon the authors called the Liking Gap. However, the logic and testing of the study existed unclear nature. In order to show whether people underestimate the positivity of impression they left on others, we directly compare the estimate of the impression we left on others with others' actual impression of us, which make the logic clear. Besides, we explored the new findings with regard to the mechanism of the effect., Methods: Based on this idea, in study 1, we explored whether there is indeed a negative deviation effect in the estimate of the impression people left on others in short interpersonal communication. In study 2, we investigated the potential psychological mechanisms of that effect., Results: In Study 1, the results revealed that people estimated that others liked them significantly less than others actually liked them. That is, a negative deviation effect did occur, and even if people were clear about their liking for others, the effect still existed. In Study 2, we provided evidence that a negative deviation effect existed not just because people are too focused on their own-negative thoughts in conversational performance but rather because people had a psychological defense towards others in their first communication., Conclusion: People significantly underestimate how much they are liked and its reason is that their psychological defense towards others in their initial communication. The results of the study are beneficial for people in social interaction and provide them with new ways of thinking in interpersonal communication and mutual contact., Competing Interests: The abstract of this paper was presented at the 22nd National Academic Congress of Psychology with the name Negative deviation effect in interpersonal communication: why people underestimate the impression they left on others, as a poster presentation with interim findings. The authors report no conflicts of interest for this work., (© 2020 Li et al.)