A novel prosthesis presentation test to screen for cognitive and functional decline.

OBJECTIVES AND BACKGROUND: To validate a novel screening test for cognitive and functional decline in older patients rehabilitated with complete removable dental prostheses (CRDPs). MATERIALS AND METHODS: Edentate old in-patients rehabilitated with CRDPs were included in this study. Participants were requested to remove their prostheses before their intraoral examinations. The prostheses were then presented in an inverted orientation. Participants had to correct the orientation of the prostheses and insert them in the appropriate jaws. The test was repeated after the intraoral exam. Appropriate statistical models were used (⍺ = .05) to associate the test results with the participants' mini-mental state examination (MMSE) score, functional independence measure (FIM), age and sex. RESULTS: Among the 86 participants (mean-age: 85.4 ± 6.4 years; mean MMSE: 19.8 ± 5.5; mean FIM: 77.9 ± 20.8), 21 (24.4%) failed to correctly insert the prosthesis. The prosthesis presentation test (PPT) was associated with the FIM but not the MMSE. Regression models further confirmed an association with age (P = .043), but not sex. Additional analyses revealed the PPT test is associated with the FIM's cognitive sub-sets of memory, problem solving and social interaction. CONCLUSION: The PPT is a novel, simple and quick screening tool that can help detect functional difficulties in older people. It can easily be performed during an oral examination. Future studies are needed to determine whether the PPT can be used to detect deficits in executive function, as a complement to the MMSE and also as a first assessment of a patient's ability to manage dentures independently.

Analysis of the residual monomer content in milled and 3D-printed removable CAD-CAM complete dentures: an in vitro study.

OBJECTIVE: The study aimed to quantitatively evaluate the elution of methylmethacrylate from CAD-CAM manufactured removable complete dentures (RCDs) using high performance liquid chromatography (HPLC). METHODS: Thirty-two RCDs were manufactured following either the CNC-milling (Milled: n=8) or the 3D-printing (n=24) protocols. The 3D-printed dentures were further categorized into three groups based on their post-production rinsing cycles [Extended wash cycle (EWC), Standard wash cycle (SWC), and SWC with an additional Durécon coating (SWC2)]. HPLC was used to evaluate the methylmethacrylate concentrations (MMCs) eluted from the dentures in each group for different time periods (1, 2, 4, 8, and 24 hours). Mean and standard deviations were calculated for the MMCs; data was verified for normal distribution, ANOVA and post hoc tests were applied for statistical analyses (⍺=0.05). RESULTS: The HPLC revealed that all the denture groups recorded some amounts of MMCs, with significant differences [F (3, 31) = 23.646, p<0.0001]. The milled denture group had the highest MMCs at 24 hours when compared to the EWC (p<0.0001), SWC (p=0.001), and SWC2 (p<0.0001) denture groups. SWC had a higher MMC than EWC (p=0.032) and SWC2 (p=0.015). No differences were found in MMCs when comparing EWC and SWC2 (p=0.989). CONCLUSION: Methylmethacrylate concentrations were significantly lower in 3D-printed RCDs than in milled RCDs when using the resins employed in this study. Furthermore, the MMCs can be further decreased in 3D-printed RCDs when coated with an additional thin protective layer (Durécon) by following the manufacturer-recommended rinsing protocol or when an extended isopropanol wash cycle is adopted.

Translation and validation of an ageism scale for dental students in Switzerland.

PURPOSE: This study aimed to validate an ageism scale for dental students in Switzerland. METHODS: The original scale was first translated to German and then evaluated by 14 experts for relevance; four items were eliminated. Validation of the resulting questionnaire was performed at three Swiss dental schools. Principal component analysis (PCA) was performed; Cronbach's alpha (α) was used to assess the internal consistency reliability, and Pearson's coefficient to identify any correlations with demographic parameters (P < 0.05). RESULTS: PCA revealed 11 items among 4 factors (Overall: 11 items, α = 0.63, variance = 56.6%; Factor #1 (F1): items = 3, α = 0.64; Factor #2 (F2): items = 3, α = 0.42; Factor #3 (F3): items = 3, α = 0.35; Factor #4 (F4): items = 2, α = 0.37). F1 and F4 were correlated with clinical experience (F1: P = 0.042; F4: P = 0.006) and participation in a gerodontology course (F1: P = 0.021; F4: P = 0.004). F1 was correlated with experience of dealing with the elderly (P = 0.031), while residence locality was correlated with F3 (P = 0.047) and F4 (P = 0.043). F2 was correlated with the presence of elderly in the family (P = 0.047). CONCLUSION: The translated dental ageism questionnaire for Switzerland resulted in an 11-item scale with acceptable reliability.

Effects of overnight storage conditions on conventional complete removable prostheses.

PURPOSE: To evaluate the effects of overnight storage conditions on the dimensional stability and retention of prostheses, as well as the participant's subjective perception of these interventions. MATERIALS AND METHODS: Subjects with maxillary complete prostheses (CRPs) were randomly assigned to receive two interventions in a crossover design: storing the CRPs overnight in a dry or wet environment with a cleansing tablet. The denture intaglio surface was scanned, and outcome measures were collected before each intervention (BLN), post ntervention (PIS), and after immersion in water for 15 minutes after the intervention (WOC). Dimensional changes were analyzed for the total surface, anterior flange, palate, and tuberosities. Retention force was measured using a dynamometer, and the participants' subjective assessment of comfort, fit, and retention of their CRPs were collected. After verifying normal distribution, paired t and Wilcoxon signed-rank tests were used to check for any statistical significance (α = .05). RESULTS: Ten participants (mean age: 76.5 ± 5.9 y) were recruited in this study. Between BLN and PIS, the dimensional changes after dry intervention were significantly less than when stored wet for total surface (P = .009), anterior flange (P = .028), and the palate (P = .005). No difference was found between the effects of storage or washout interventions on objectively measured CRP retention. However, after WOC following dry storage, participants perceived a lower retention (P = .021), and a more comfortable palate after WOC following the wet intervention (P = .018). CONCLUSION: For dimensional stability, dry overnight storage of removable prostheses can safely be recommended when indicated. Immersion in water for 15 minutes does not seem to add advantages.

CAD-CAM complete removable dental prostheses: A double-blind, randomized, crossover clinical trial evaluating milled and 3D-printed dentures.

OBJECTIVE: This double-blind, randomized, crossover, clinical trial aimed to evaluate and compare the differences between milled and 3D-printed complete removable dental prostheses (CRDPs). METHODS: Fifteen edentulous patients (men: n = 10, women: n = 5; age: 66.7 ± 8.0 years) rehabilitated with conventional CRDPs were recruited for this trial. Participants were randomized to first receiving either the milled or 3D-printed CAD-CAM manufactured CRDPs and then after 6-weeks cross over to the other set. Both, clinicians and participants were blinded to the group allocation. Outcomes included patient's denture satisfaction (PDS), oral-health related quality of life (OHIP-EDENT), willingness-to-pay analysis, final choice (FC) of CRDPs, clinician's denture quality evaluation (CDQE), chewing efficiency (CE), maximum-voluntary-bite-force (MBF), and prosthodontic maintenance needs. The outcomes were measured at baseline (with old CRDPs), at 1 and 6 weeks after new CRDP insertion; following crossover with the second set of CRDPs, an identical protocol was followed. Generalized linear regression for repeated measures was used for statistical analysis with α=0.05. RESULTS: All participants completed the trial. 3D-printed CRDPs required more maintenance visits, adjustment time (p = 0.0003), and adjustment costs (p = 0.021). Patients were willing-to-pay an average of 606.67 Swiss Francs more than the actual cost for the milled CRDPs. There were no differences in the PDS, OHIP, FC, CDQE, CE, and MBF between the two CRDPs groups. CONCLUSIONS: The findings of this double-blind randomized crossover clinical trial confirm that both milled and 3D-printed CRDPs are valid treatment modalities for edentulous patients, with the latter performing inferiorly with regard to the time and costs involved with the prosthodontic aftercare, as well as the patients' willingness-to-pay. CLINICAL RELEVANCE: The findings of this trial provide evidence to help the clinician in choosing the appropriate CAD-CAM manufacturing process for fabricating the CRDPs.

Extra-oral assessment of conventional and CAD-CAM complete denture appearance by dental professionals and CRDP wearers: A randomized survey.

INTRODUCTION: Complete removable dental prostheses' (CRDPs) appearance may vary between conventional and contemporary CAD-CAM manufacturing techniques. OBJECTIVES: The aim of this randomized survey was to analyze appreciation of CRDPs, manufactured with different techniques, by dental professionals and elder CRDP wearers. METHODS: Four participant groups, comprised of undergraduate students (n=10), postgraduate residents (n=10), dental technicians (n=10) and elder CRDP wearers (n=10), evaluated the appearance of maxillary CRDPs manufactured by six different techniques: three conventional methods 1. flask-pack-press (FP), 2. Injection-molded (IM), 3. intrinsically colored natural gingiva finish before injection-molded (NG) and three CAD-CAM methods 4. milled base with bonded prefabricated teeth (M), 5. fully milled including milled teeth (FM) and 6. rapid-prototyped including printed teeth (P). A randomized, blinded survey included 18 pairwise comparative assessments and 12 individual judgements of the CRDPs on general appearance as well as pink and white aspects. Statistical analyses included parametric- and nonparametric tests as well as linear regression models; the level of statistical significance was set at p<.05. RESULTS: NG was preferred by the professional groups but not by the elder CRDP wearers (p<.05). P was scored lowest by all four participant groups (p<.05). CRDP wearers' ratings were less severe and within a narrower range. The ratings of the two CAD-CAM milled CRDPs (M and FM) were ranked closer to FP and IM); the order of preference was different depending on the participant groups. CONCLUSIONS: The findings of this study revealed marked differences in the assessment of CRDP appearances between dental professionals and older CRDP wearers. CLINICAL SIGNIFICANCE: A shared and informed approach to decision making concerning the CRDP appearance might foster denture acceptance and treatment success.

CAD-CAM complete denture resins: an evaluation of biocompatibility, mechanical properties, and surface characteristics.

OBJECTIVES: This study evaluated the biocompatibility, mechanical properties, and surface roughness of CAD-CAM milled and rapidly-prototyped/3D-printed resins used for manufacturing complete dentures. METHODS: Six groups of resin specimens were prepared, milled-base (MB), milled-tooth shade (MT), printed-tooth shade (PT), printed-base with manufacturer-recommended 3D-printer (PB1), printed-base with third-party 3D-printer (PB2), printed-base in a vertical orientation (PB2V). Human epithelial (A-431) and gingival (HGF-1) cells were cultured and tested for biocompatibility using Resazurin assays. Three-point bending and nanoindentation tests measured the mechanical properties of the resin groups. Surface roughness was evaluated using a high-resolution laser profilometer. ANOVA and post-hoc tests were used for statistical analyses (α = 0.05). RESULTS: There were no significant differences in biocompatibility between any of the investigated groups. MB revealed a higher ultimate strength (p = 0.008), elastic modulus (p = 0.002), and toughness (p = 0.014) than PB1. MT had significantly higher elastic modulus than PT (p < 0.001). Rapidly-prototyped resin samples with a manufacturer-recommended 3D-printer (PB1) demonstrated higher ultimate strength (p = 0.008), elastic modulus (p < 0.001), hardness (p < 0.001) and a reduced surface roughness (p < 0.05) when compared with rapidly-prototyped groups using a third-party 3D-printer (PB2). Rapidly-prototyped samples manufactured with a vertical printing orientation (PB2V) revealed a significantly lower elastic modulus than samples groups manufactured using horizontal printing orientation (PB2) (p = 0.011). CONCLUSIONS: Within the limits of this present study, CAD-CAM milled and rapidly-prototyped complete denture resins performed similarly in terms of biocompatibility and surface roughness. However, the milled denture resins were superior to the rapidly-prototyped denture resins with regard to their mechanical properties. Printing orientation and type of 3D-printer can affect the resin strength and surface roughness.

Attitudes of dental students towards treating elderly patients. Dental students' attitudes on geriatric patients

The purpose of this questionnaire-based survey was to evaluate the attitudes of the undergraduate dental students towards elders. The 14-item Geriatric attitudes scale (GAS) questionnaire, along with a 9-item questionnaire with specific questions on the current geriatric dental curriculum, confidence, and preference in treating the elderly patients were administered to the undergraduate dental students (3rd bachelor, 1st master, and 2nd master) in the four Swiss university dental schools. Mean GAS scores were calculated and inter- and intra-group differences were analyzed with ANOVA and post hoc tests (level of significance set at α=0.05). Responses to the 9-item questionnaire were reported descriptively. Further analyses were performed to evaluate the effect of demographic factors on the GAS scores. 305 students (meanage: 25.8±4.0y) participated in this study. The mean overall GAS score of the students was 3.5±0.4. There were no significant differences in the GAS scores between the centers [F(3, 300)=2.266, p=0.081] or between the year of training [F(2, 301)=1.884, p=0.154]. Demographic factors did not influence the GAS scores. Students considered geriatric dentistry as an important part of their dental undergraduate education. The current geriatric curriculum was perceived to be on an adequate level. Hands-on experience in treating geriatric patients in the undergraduate curriculum was positively opinionated, and mobile dental services for elders with limited access to care was considered a good solution. In conclusion, the attitudes of the Swiss undergraduate dental students towards an elderly patient seem acceptable but could still be improved.

In silico evaluation of the peripheral and inner seals in complete denture master impressions using a custom-developed 3D software.

OBJECTIVES: Despite the complexity of the edentulous anatomy, little evidence exists as to what impression techniques and materials should be employed for an optimal result. The aim of this in silico study was to evaluate the trueness of peripheral and inner seals of different edentulous jaw impressions. MATERIALS AND METHODS: Twelve maxillary edentulous participants (male = 8, female = 4; age 68.5 ± 11.7 years) participated in this study. Four different impression materials and techniques, irreversible hydrocolloid (Alginate; Blueprint X-Crème, Dentsply Sirona, PA, USA), polyvinyl siloxane impression (PVS; Aquasil Ultra+ Medium, Dentsply Sirona, PA, USA), and subsequently modified with ZnOE (PVSM) and an optical impression (Optical; 3Shape A/S, Copenhagen, Denmark), were tested against a control impression: low-fusing impression compound border molding (Kerr Corp., CA, USA) followed by a ZnOE impression (ZnOE; SS White impression paste, S.S. White Group, Gloucester, England). All impressions were scanned and analyzed using a custom-built 3D comparison software analyzing the vertical and horizontal trueness. RESULTS: The vertical discrepancy (peripheral seal) of the impression surface was significantly more true for PVSM than Alginate (p = 0.001), PVS (p = 0.019), and Optical groups (p < 0.001). Where the horizontal discrepancy (inner seal) was compared, the impression surface was more true for PVSM than Alginate (p < 0.001) and Optical (p < 0.001). PVS group was also significantly more true than Optical (p = 0.015). CONCLUSION: Impression techniques and materials may significantly influence the peripheral and inner seal of an edentulous jaw impression. CLINICAL RELEVANCE: When using a polyvinylsiloxane impression material for master edentulous impressions, a selective inner seal reline with a conventional zinc oxide eugenol impression paste can improve the inner seal.

Comparison of smartphone-camera and conventional flatbed scanner images for analytical evaluation of chewing function.

BACKGROUND: The two-colour mixing test is a quick method to assess chewing function (CF). The use of smartphone cameras for acquiring images may help in further simplifying the process. OBJECTIVE: This study evaluated the reliability of smartphone-camera images of chewing gums to assess CF. METHODS: Five test samples of a bicoloured chewing gum were produced by a single fully dentate adult volunteer. The specimens were flattened to 1-mm thick wafers. The two sides of the wafers were digitised with a conventional flatbed scanner (control) and were photographed 20 times using 8 different smartphones. The images were assessed optoelectronically to obtain the variance of hue (VoH) and subjectively by visual assessment (SA) using a categorical scale (SA1-SA5). Spearman's correlation and regression models were used for statistical analyses. RESULTS: The intra-group variability for SA1-SA3 was <1% for all smartphones, but significantly higher than controls for SA4 and SA5 (smartphone: SA4 = 5.57%; SA5 = 8.76%; control: SA4 = 2.5%; SA5 = 0.79%). VoH was progressively lower from SA1 to SA5 for all imaging devices (r > -.97; P < .001). VoH comparisons between control and smartphone images revealed significant differences for the individual SA categories, and however, the magnitude of differences was small and non-significant when the full range of SA levels were considered. The linear mixed model regression showed significant effects for all the smartphones (P < .001) and SA levels (P < .001) in relation to the flatbed scanner values. CONCLUSIONS: Smartphone cameras may be used to evaluate colour mixture for a bolus-kneading test, however, the precision is lower with higher degrees of colour mixing.

Histomorphological assessment of isolated abdominal organs after targeted perfusion with the contrast agent Angiofil® in postmortem computed tomography angiography.

The current literature about histological alterations and artefacts associated with postmortem computed tomography angiography (PMCTA) is scarce and limited to qualitative research. The aim of this study was to describe and quantify histological alterations and artefacts in histologic specimens of the inner organs. The spleen, the liver, the kidneys and the pancreas were eviscerated in the course of standard forensic autopsy, followed by manual arterial and venous perfusion of the organs with the lipophilic contrast agent Angiofil®. Computed tomography (CT) of the organ packages was executed to evaluate if the perfusion with Angiofil® was sufficient. The CT scans revealed a good delineation of the vessel trees up to the organ periphery, suggesting a sufficient perfusion. Tissue samples were taken before and after perfusion, stained with hematoxylin-eosin (H&E) and examined by using microscopy. Native and perfused specimens were assessed on the basis of a qualitative rating scale in regard to the integrity of the cells, the tissue architecture and induced alterations. Subsequently the observed differences before and after perfusion with Angiofil® were analyzed quantitatively. While the liver, spleen and kidneys could be evaluated, further microscopic examinations of the pancreatic tissue were not possible due to vast autolytic changes. On the cellular level no changes in the liver, spleen and kidneys were observed after administering Angiofil®. While the tissue architecture of these organs remained intact, a significant blood volume displacement occurred. As a consequence, tissue with hypoemic or normal blood state demonstrated congestion. Further, optically empty spaces emerged regularly in the vessels and the parenchyma of each organ as a surrogate for the lipophilic contrast agent. With a few exceptions an adequate perfusion up to the microscopic level was observed. Following the results of this investigation, CT-controlled manual injection of Angiofil® into isolated organs may be an alternative to the generalized in situ application of contrast agents in the course of PMCTA. It is of eminent importance to know the artefacts induced by an Angiofil® injection in order to avoid a misinterpretation or a masking of findings. Thus, a collection of native tissue specimens has to be done before contrast agent application.

CAD-CAM milled dentures: The Geneva protocols for digital dentures.

This technical report describes 2 workflows for fabricating computer-aided design and computer-aided manufacturing (CAD-CAM) milled complete dentures (CDs). The first technique illustrates a manufacturer-independent workflow using conventional clinical steps and a novel, custom modified tray to successfully fabricate CAD-CAM milled CDs. The second technique highlights a nearly digital workflow for manufacturing a CAD-CAM milled CD and a milled resin interim removable partial denture.

Implant overdentures retained by self-aligning stud-type attachments: A clinical report.

The functionality of a new overdenture attachment (LOCATOR R-Tx) was described for different clinical situations: a conventional mandibular implant overdenture (IOD) retained by 2 implants, a straightforward chairside maintenance procedure for replacing a worn LOCATOR (Legacy) attachment with the new LOCATOR R-Tx, and a complex clinical situation with nonideal implant positions with compromised parallelism. The LOCATOR R-Tx is an advance on the existing LOCATOR Legacy attachment and has an improved abutment head design with a more durable surface coating to prevent attachment wear and thereby reduce frequency of maintenance.

Implant-Retained Overdentures Using an Attachment with True-Alignment Correction: A Case Series.

Implant parallelism is considered a cardinal criterion for the successful rehabilitation of edentulous jaws with implant-retained overdentures (IODs), especially if freestanding anchorage systems (unsplinted attachments) are employed. This report aimed to demonstrate the successful use of a novel IOD attachment with a true-alignment capability in complex cases with large inter-implant angular discrepancies. The report further aimed to highlight the use of a novel polyetherketoneketone (PEKK) framework as a reinforcement material for fabricating a completely metal-free IOD. Although some freestanding attachments exploit their geometric form and/or use various retentive inserts to compensate for inter-implant angular discrepancies, a true-alignment correction is seldom achieved. The CM LOC FLEX (Cendres+Métaux attachment provides a true alignment correction and produces parallelism between implants in clinical situations where the implants are not parallel to one another. The functionality of the CM LOC FLEX was described in this case report for two different clinical situations: a conventional mandibular IOD retained by two implants, and a maxillary IOD retained by four implants. Both cases involved a complex clinical situation with compromised implant parallelism. The CM LOC FLEX abutment has a true-alignment correction mechanism that can be advantageous in clinical situations where the inter-implant axial alignments are not parallel. PEKK frameworks are lightweight, strong, and can be esthetic substitutes for conventional metal frameworks. However, well-designed clinical studies are further needed to assess the clinical performance as well as the maintenance requirements of the illustrated novel attachment and the PEKK framework before advocating them as validated and standard protocols.

CAD-CAM milled versus rapidly prototyped (3D-printed) complete dentures: An in vitro evaluation of trueness.

STATEMENT OF PROBLEM: Complete dentures fabricated by computer-aided design and computer-aided manufacturing (CAD-CAM) techniques have become popular. The 2 principal CAD-CAM techniques, milling and rapid prototyping (3D printing), used in the fabrication of complete dentures have been reported to yield clinically acceptable results. However, clinical trials or in vitro studies that evaluated the accuracy of the 2 manufacturing techniques are lacking. PURPOSE: The purpose of this in vitro study was to compare the differences in trueness between the CAD-CAM milled and 3D-printed complete dentures. MATERIAL AND METHODS: Two groups of identical maxillary complete dentures were fabricated. A 3D-printed denture group (3DPD) (n=10) and a milled denture group (MDG) (n=10) from a reference maxillary edentulous model. The intaglio surfaces of the fabricated complete dentures were scanned at baseline using a laboratory scanner. The complete dentures were then immersed in an artificial saliva solution for a period of 21 days, followed by a second scan (after immersion in saliva). A third scan (after the wet-dry cycle) was then made after 21 days, during which the complete dentures were maintained in the artificial saliva solution during the day and stored dry at night. A purpose-built 3D comparison software program was used to analyze the differences in the trueness of the complete dentures. The analyses were performed for the entire intaglio surface and specific regions of interest: posterior crest, palatal vault, posterior palatal seal area, tuberosity, anterior ridge, vestibular flange, and mid-palatal raphae. Independent t tests, ANOVA, and post hoc tests were used for statistical analyses (α=.05). RESULTS: The trueness of the milled prostheses was significantly better than that of the rapid prototyping group with regard to the entire intaglio surface (P<.001), posterior crest (P<.001), palatal vault (P<.001), posterior palatal seal area (P<.001), tuberosity (P<.001), anterior ridge (baseline: P<.001; after immersion in saliva: P=.001; after the wet-dry cycle: P=.011), vestibular flange (P<.001), and mid-palatal raphae (P<.001). CONCLUSIONS: The CAD-CAM, milled complete dentures, under the present manufacturing standards, were superior to the rapidly prototyped complete dentures in terms of trueness of the intaglio surfaces. However, further research is needed on the biomechanical, clinical, and patient-centered outcome measures to determine the true superiority of one technique over the other with regard to fabricating complete dentures by CAD-CAM techniques.

Edentulous jaw impression techniques: An in vivo comparison of trueness.

STATEMENT OF PROBLEM: Simplified edentulous jaw impression techniques have gained popularity, while their validity has not yet been evaluated. PURPOSE: The purpose of this clinical study was to compare the trueness of maxillary edentulous jaw impressions made with irreversible hydrocolloid (ALG), polyvinyl siloxane (PVS), PVS modified with zinc oxide eugenol (ZOE) (PVSM), and an intraoral scanner (TRI) with a conventionally border-molded ZOE impression (control). MATERIAL AND METHODS: Twelve edentulous maxillary impressions were made with the impression techniques. The analog impressions were scanned using a laboratory scanner, imported into 3-dimensional comparison software, and superimposed against the corresponding control. Trueness was evaluated by calculating the effective deviation known as root mean square (RMS) for the entire surface (ES) and for specific regions of interest such as peripheral border, inner seal, midpalatal suture, ridge, and posterior palatal seal. The secondary outcomes for this study were the patients' perception of the impression techniques. Statistical analyses with the Wilcoxon tests were carried out (α=.05). RESULTS: For ES, significant differences were found when comparing ALG (1.21 ±0.35 mm) with PVS (0.75 ±0.17 mm; P=.008), PVSM (0.75 ±0.19 mm; P=.012), and TRI (0.70 ±0.18 mm; P=.006) but not among the other groups. Significant differences were found for peripheral border when comparing ALG (2.03 ±0.55 mm) with PVS (1.12 ±0.32 mm; P=.006), PVSM (1.05 ±0.29 mm; P=.003), and TRI (1.38 ±0.25 mm; P=.008), as well as TRI and PVSM (P=.028). Significant differences were also found for inner seal when comparing ALG (0.74 ±0.36 mm) with PVSM (0.52 ±0.13 mm; P=.041), as well as TRI (0.8 ±0.25 mm) versus PVS (0.56 ±0.14 mm; P=.005) and PVSM (P=.005). The difference at the ridge was significant when comparing PVS (0.18 ±0.07 mm) with PVSM (0.28 ±0.19 mm; P=.015) but not among the other groups. A significant difference was also found for posterior palatal seal when comparing PVS (0.55 ±0.41 mm) with PVSM (0.60 ±0.43 mm; P=.034). Patient perceptions showed significantly better satisfaction scores for ALG (1.83 ±2.03) and PVS (3.17 ±2.40) than for TRI (4.08 ±2.71), PVSM (4.58 ±2.35), and ZOE (6.83 ±1.75). CONCLUSIONS: Edentulous impressions made with PVS, PVSM, and TRI had similar deviations and may yield clinically acceptable results. Irreversible hydrocolloids are contraindicated for definitive impression making in completely edentulous jaws.

A user-friendly technical set-up for infrared photography of forensic findings.

Infrared photography is interesting for a use in forensic science and forensic medicine since it reveals findings that normally are almost invisible to the human eye. Originally, infrared photography has been made possible by the placement of an infrared light transmission filter screwed in front of the camera objective lens. However, this set-up is associated with many drawbacks such as the loss of the autofocus function, the need of an external infrared source, and long exposure times which make the use of a tripod necessary. These limitations prevented up to now the routine application of infrared photography in forensics. In this study the use of a professional modification inside the digital camera body was evaluated regarding camera handling and image quality. This permanent modification consisted of the replacement of the in-built infrared blocking filter by an infrared transmission filter of 700nm and 830nm, respectively. The application of this camera set-up for the photo-documentation of forensically relevant post-mortem findings was investigated in examples of trace evidence such as gunshot residues on the skin, in external findings, e.g. hematomas, as well as in an exemplary internal finding, i.e., Wischnewski spots in a putrefied stomach. The application of scattered light created by indirect flashlight yielded a more uniform illumination of the object, and the use of the 700nm filter resulted in better pictures than the 830nm filter. Compared to pictures taken under visible light, infrared photographs generally yielded better contrast. This allowed for discerning more details and revealed findings which were not visible otherwise, such as imprints on a fabric and tattoos in mummified skin. The permanent modification of a digital camera by building in a 700nm infrared transmission filter resulted in a user-friendly and efficient set-up which qualified for the use in daily forensic routine. Main advantages were a clear picture in the viewfinder, an auto-focus usable over the whole range of infrared light, and the possibility of using short shutter speeds which allows taking infrared pictures free-hand. The proposed set-up with a modification of the camera allows a user-friendly application of infrared photography in post-mortem settings.

Clinical predictive factors for temporomandibular disorders following combined orthodontic and orthognathic surgical treatment in patients with Class III malocclusion.

OBJECTIVE: The aim of this study was to identify clinical factors predisposing to the development or worsening of temporomandibular disorders (TMDs) following orthodontic surgical treatment for Class III malocclusion. METHODS: A retrospective cohort study was performed on 88 patients with Class III malocclusion having undergone a combined orthodontic and orthognathic surgical treatment. Temporomandibular joint and masticatory muscle examinations were available prior to treatment and one year post-operatively. Multivariate logistic regression was used to predict the development of post-operative TMDs, and linear regression was used to predict the worsening of TMDs using Helkimo indices. RESULTS: Patients with Class III malocclusion presenting with pre-treatment anamnestic TMJ clicking (OR = 5.8; p = 0.03) and undergoing bimaxillary osteotomy procedures (OR = 18.6; p = 0.04) were more at risk for the development of TMDs. DISCUSSION: TMDs must be evaluated, monitored, and managed with caution in patients with Class III malocclusion presenting with pre-treatment joint clicking and who are planned for bimaxillary osteotomies.