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1.
Data Brief ; 56: 110861, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39286418

RESUMEN

Drying of mushroom up to the optimal moisture content is an important preservation technique. This research contains data of the drying kinetics, moisture sorption isotherm, and evaluation of the important functional groups of fresh and dried oyster mushroom (Pleurotus ostreatus) while drying in tray dryer using hot air-drying medium. Mushrooms contains macronutrients that used as supplementary foods and moisture that make it perishable with in short time. Various drying kinetics models at different temperatures (50, 55, 60, 65, 70, and 75 °C) for was studied for oyster mushroom drying. The drying parameters (drying temperature, air speed and mass of mushroom) of mushroom in tray dryer were optimized. Fourier transform infrared (FTIR), and Atomic Absorption Spectroscopy (AAS) was used to investigate the useful functional groups and minerals composition of the dried and fresh oyster mushroom. Further proximity study was conducted. This dataset is publicly available for researchers, industrial sectors, and research laboratory to optimize and save time.

2.
Cureus ; 16(8): e66732, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39268280

RESUMEN

Edentulism, the loss of all the natural teeth, significantly impacts a patient's functional, aesthetic, and psychological well-being. Traditional dentures often fail to provide the required stability and functionality. Implant-supported full-mouth rehabilitation has emerged as an advanced solution, leveraging strategically placed dental implants to support fixed prostheses that mimic natural teeth in appearance and function. This case report details the comprehensive treatment of a 78-year-old male patient with complete edentulism, utilizing six implants in both the maxillary and mandibular arches. Following a five-month healing period, a series of precise prosthetic procedures, including abutment-level impressions, custom tray fabrication, and implant-level impressions, were performed to ensure optimal fit and functionality. The final prostheses provided significant improvements in masticatory efficiency, speech, and overall quality of life. The report underscores the transformative potential of implant-supported rehabilitation, highlighting high success rates, patient satisfaction, and the multifaceted benefits of restoring oral function and aesthetics with advanced dental technologies.

3.
Angle Orthod ; 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-39195165

RESUMEN

OBJECTIVES: To compare the transfer accuracy of two different indirect bonding (IDB) trays. MATERIALS AND METHODS: Digital IDB was performed on a total of 30 patients using one of two designs: shell and bar trays, with 15 patients in each group. Trays were designed with the Appliance Designer software (3Shape A/S, Copenhagen, Denmark). Angular (torque, tip, angulation) and linear (mesiodistal, buccolingual, occlusogingival) differences were compared between the bonded intraoral scans taken immediately after IDB and the virtually bracketed model prepared in Ortho Analyzer software (3Shape A/S) using open source GOM inspect software (GOM GmbH, Braunschweig, Germany). RESULTS: There were no significant differences found between the bar and shell groups. Within the groups, significant tip differences were found between the incisors, canines, and premolars in both groups (P = .0001). Additionally, a statistically significant torque difference was found in the canines and incisors in the shell group. The percentage of values that deviated from the clinical acceptance limit was relatively higher in the bar group. CONCLUSIONS: Although there was no statistical difference between groups, the shell tray showed better results according to clinical acceptability limits. This study is important as it is the first clinical study to compare directly printed transfer trays with different designs.

4.
MethodsX ; 13: 102864, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39092278

RESUMEN

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.

5.
AAPS J ; 26(5): 89, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39150583

RESUMEN

A non-invasive capacitance instrument was embedded in the base of a vacuum-drying tray to monitor continuously the residual amount of solvent left in a pharmaceutical powder. Proof of concept was validated with Microcrystalline Cellulose laced with water, as well as water/acetone mixtures absorbed in a spray-dried Copovidone powder. To illustrate the role of impermeability of the base, we derive a model of vapor sorption that reveals the existence of a kinetic limit when solids are thinly spread, and a diffusion limit with greatly diminished effective diffusivity at large powder thickness. By monitoring the residual solvent content of powders, this new in situ technique offers advantages over indirect methods like mass spectrometry of vapor effluents, but without complications associated with probe fouling. To prescribe design guidelines and interpret signals, we model the electric field shed by the probe when a powder holds variable solvent mass fraction in the vertical direction.


Asunto(s)
Celulosa , Polvos , Solventes , Solventes/química , Vacio , Celulosa/química , Celulosa/análisis , Pirrolidinas/química , Pirrolidinas/análisis , Compuestos de Vinilo/química , Agua/química , Desecación/métodos , Acetona/análisis , Acetona/química , Difusión , Cinética
6.
Foods ; 13(16)2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39200413

RESUMEN

To obtain oil from bee brood, which was dried using a tray drying method, this study used the supercritical CO2 extraction method. Extraction occurred at temperatures between 40-60 °C and low pressures of 180-220 bar for 1.5 h, with a high pressure of 600 bar for 1 h. The study investigated both the yield and chemical properties of the extracted bee brood oils. Supercritical CO2 extraction of tray-dried bee brood at 600 bar pressure demonstrated higher oil extraction efficiency compared to lower pressures (180-220 bar). At temperatures of 40-60 °C, total phenolic compounds increased while total flavonoids decreased. The extracted oil exhibited antioxidant activity, primarily due to quercetin. Despite decreased acid, iodine, and saponification values, peroxide value slightly increased but remained below 12 meqO2/kg of oil. The make-up of the fatty acids changed. At 600 bar, palmitic and oleic acids were the most common, while myristic, linoleic, and docosadienoic acids decreased. At 600 bar, eicosadienoic acid was absent. The defatted bee brood retained significant essential and non-essential amino acids, indicating its potential for further development as a protein source.

7.
Clin Nutr ESPEN ; 62: 43-56, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38901948

RESUMEN

BACKGROUND & AIMS: Over $150,000 are lost annually due to meal tray waste in a large hospital in the United States. This study aims to explore the root causes of meal tray waste within a decentralized foodservice model and strategies to mitigate waste. METHODS: A mixed methods sequential explanatory design was used by first identifying hospital units high and low in meal tray waste using recorded food management data from January 2021 through September 2022, then conducting observations, mobile-interviews (n = 16), and in-depth interviews with hospital foodservice staff (n = 6) and nurses (n = 6) in each unit. Lastly, hospital and topic experts (n = 10) were engaged in strategizing solutions to reduce meal tray waste. RESULTS: Findings indicate meal tray waste is increased when patients discharge and when standard trays (i.e., also known as house trays, which include items not requested by patients) are provided. Meal tray waste points to the unpredictability in a hospital that often arises due to patient circumstances, lack of coordination between nursing and foodservice staff, patients' food preferences, and the need for system and workflow improvements in a decentralized foodservice model. CONCLUSIONS: Findings highlight considerations that may be applicable across diverse medical institutions seeking to reduce meal tray waste. Hospitals should choose the best foodservice model that suits their institution to manage operations efficiently, focusing on reducing waste, cost optimization, patient satisfaction, and sustainability.


Asunto(s)
Servicio de Alimentación en Hospital , Comidas , Humanos , Estados Unidos , Hospitales , Administración de Residuos/métodos
8.
Heliyon ; 10(11): e32035, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38867963

RESUMEN

With the advancement of 3-dimensionally (3D) printing technology, orthodontists can design and fabricate 3D-printed indirect bonding trays and transfer jigs for lingual brackets independently from the laboratory. The present article describes, in detail, the digital workflows for designing and fabricating 3D-printed lingual bracket indirect bonding trays and transfer jigs. Additionally, it aims to demonstrate the effectiveness of this approach in managing common orthodontic issues in adult patients. The first case report exemplifies the successful management of moderate crowding in a Class I adult patient using a non-extraction approach with lingual brackets and flexible 3D-printed indirect bonding trays. The second case illustrates the application of lingual brackets and rigid 3D-printed indirect bonding trays in managing a skeletal Class II adult patient with mouth protrusion requiring four-bicuspid extractions. The achieved good treatment results might demonstrate the high transfer accuracy of 3D-printed lingual bracket indirect bonding trays. Additional studies with large sample sizes should be conducted to compare the effectiveness and efficiency of 3D-printed trays with other tray types.

9.
Materials (Basel) ; 17(10)2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38793327

RESUMEN

This study aimed to evaluate the effect of ceramic type, firing tray, and firing substrate on the density, shrinkage, biaxial flexural strength, Martens' hardness, and elastic indentation modulus of zirconia veneering ceramics. Disk-shaped specimens were fabricated from a high-fusing (HFZ) and a low-fusing (STR) zirconia veneering ceramic. These specimens were then divided into 10 groups according to firing trays (round, small honeycomb-shaped, cordierite [RSC]; round, large honeycomb-shaped, aluminum oxide [RLA]; rectangular, plane, silicon nitride [RCPS]; round, plane, silicon nitride [RPS]; and rectangular, plane, calcium silicate [RCPC]) and firing substrates (firing cotton and platinum foil) used (n = 12). The density, shrinkage, biaxial flexural strength, Martens' hardness, and indentation modulus were measured, and analyzed with generalized linear model analysis (α = 0.05). The interaction between the ceramic type and firing substrate affected density (p < 0.001), and the other outcomes were affected by the interaction among all main factors (p ≤ 0.045). Higher density was observed with HFZ or platinum foil (p ≤ 0.007). RSC and RLA led to a higher density than RCPS within HFZ and led to the lowest density within STR (p ≤ 0.046). STR had a higher shrinkage (p < 0.001). RSC mostly led to a lower shrinkage of HFZ (p ≤ 0.045). The effect of ceramic type and firing substrates on the biaxial flexural strength, Martens' hardness, and indentation modulus was minimal while there was no clear trend on the effect of firing tray on these properties. Ceramic type, firing tray, and firing substrate affected the mechanical properties of the tested zirconia veneering ceramics. Firing the tested zirconia veneering ceramics over a round and small honeycomb-shaped cordierite firing tray with firing cotton mostly led to improved mechanical properties.

10.
Cureus ; 16(4): e59193, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38807829

RESUMEN

Aim The aim of this in vitro study was to evaluate and compare the accuracy of casts made from two elastomeric impression materials (polyvinyl siloxane (PVS) and vinylsiloxanether (VSE)) using different impression techniques on parallel and angulated implants. Materials and methods The reference model was fabricated using auto-polymerizing acrylic resin on which three implant analogs were placed of which two were parallel to each other and the third at 20-degree mesial angulation. A total of 60 impressions were made of which 30 were by using PVS and 30 by VSE. For each material, 10 impressions were made by closed tray technique, 10 by open tray technique and 10 by open tray with sandblasting and adhesive coating of the impression copings technique. The inter-analog distances of the casts obtained were evaluated and compared with the reference model by a vision measuring machine. Data were analyzed using analysis of variance (ANOVA), Tukey's Honest Significant Difference (HSD) post hoc and independent samples t-test. Results When the inter-analog distances of the duplicate casts were compared with the reference model, the mean error rates for parallel implants decreased in the order of closed tray technique, open tray technique and open tray with sandblasting and adhesive coating of the impression copings technique for both PVS and VSE impression materials. Similarly, the same order was observed for angulated implants for both impression materials. Using the closed tray technique, there was no statistically significant difference in the accuracy of the cast between the two materials for parallel implants (P = 0.525) and also no significant difference between the two materials for angulated implants (P = 0.307). Similarly, there was no statistically significant difference in the accuracy of the cast between the two materials for parallel implants (P = 0.455) and also no significant difference between the two materials for angulated implants (P = 0.519) using the open tray technique. Whereas for the open tray with sandblasting and adhesive coating of the impression copings technique, VSE produced a more accurate cast than PVS for parallel implants and was statistically significant (P = 0.033); however, there was no significant difference between the two materials for angulated implants (P = 0.375). Conclusion For parallel implants, VSE by an open tray with sandblasting and adhesive coating of the impression copings technique produced a more accurate cast than PVS. For angulated implants, there was no significant difference between the two materials and it was only the technique that significantly affected the accuracy of the cast.

11.
Int J Prosthodont ; 0(0): 1-20, 2024 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-38758587

RESUMEN

PURPOSE: To determine whether digital training improves conceptual skills acquisition for custom tray fabrication and tooth arrangement in the preclinical curriculum for complete denture fabrication. MATERIALS AND METHODS: A crossover design study compared third-year student grades after conventional (manual) and digital training. Half the students were trained with conventional techniques prior to digital, while the other half were trained with digital techniques prior to conventional. The first part of the study (DP1) focused on custom tray fabrication and involved 154 students. The second part (DP2) focused on tooth arrangement with 204 students. The effect of preliminary digital training on conceptual skills was assessed by comparing the results of the students using a Student's t-test. Results were also analyzed by ranking on the students' Perceptual Ability Test (PAT) score. Finally, students' satisfaction with the training was investigated. RESULTS: Students who completed the initial digital session achieved better custom tray fabrication and tooth arrangement in the subsequent manual sessions. For manual laboratory work, the most dexterous students (PAT1 group) demonstrated the best performance. However, PAT2 students had the best performance during the digital sessions during DP1, and PAT1 and PAT2 students had the best performance during the digital sessions during DP2. Additionally, 40% of DP1 and 12% of DP2 students expressed satisfaction with digital sessions. CONCLUSION: With complementary manual and digital teaching, digital tools may be useful for enhanced student learning. Digital training has contributed to improve results in manual sessions but did not affect student satisfaction and remained a limited tool to detect learning difficulties.

12.
Artículo en Inglés | MEDLINE | ID: mdl-38754541

RESUMEN

BACKGROUND: The influence of position of the humeral tray (inlay or onlay) on clinical outcomes in reverse shoulder arthroplasty (RSA) is a topic of debate. The purpose of this study was to compare clinical and radiographic outcomes of patients with cuff tear arthropathy treated with RSA systems with inlay or onlay humeral tray design, similar neck-shaft angles, and lateralized glenospheres. METHODS: This was a retrospective study of prospectively obtained data from 1 tertiary care center. We identified all patients who underwent primary RSA between 2009 and 2017 (N = 511). We included 102 patients with diagnosed cuff tear arthropathy treated with RSA prostheses with a lateralized glenosphere and 135° neck-shaft angle (with either an inlay or onlay humeral tray design) who had a minimum of 2 years of follow-up (mean, 44 months; range, 24-125 months). Sixty-three patients (62%) had an inlay humeral tray (inlay group) and 39 (38%) had an onlay tray (onlay group). All patients underwent preoperative and postoperative evaluations, including measures of patient-reported outcomes (PROs), shoulder range of motion (ROM) testing, and radiographic imaging. Clinical relevance of changes in PROs and ROM was evaluated using published values for minimal clinically important differences. RESULTS: The 2 groups did not differ by demographic characteristics except for a higher proportion of women in the inlay group (75%) than in the onlay group (56%) (P = .04). Preoperative PROs and ROM were not significantly different between groups. At final follow-up, PROs and ROM were not different between groups in terms of statistical significance or clinical relevance. We found no significant differences in the rate of baseplate loosening (inlay, 3.2% vs. onlay, 5.1%, P = .63), revision surgery (inlay, 0% vs. onlay 5.1%, P = .07), acromial stress fracture (inlay, 3.2% vs. onlay, 5.1%, P = .63), prosthesis dislocation (inlay, 0% vs. onlay, 2.6%, P = .20), or scapular notching (inlay, 21% vs. onlay, 7.7%, P = .08). CONCLUSION: At 2-year minimum follow-up, the position of the humeral tray in RSA prostheses (either inlay or onlay) for cuff tear arthropathy was not associated with PROs, shoulder ROM, or rates of complications, including baseplate loosening, acromial stress fracture, and scapular notching.

13.
BMC Oral Health ; 24(1): 555, 2024 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-38735948

RESUMEN

OBJECTIVE: This study aimed to evaluate the effect of fence tray matching care (FTMC) in bracket bonding by measuring excess adhesive, as well as linear and angular deviations, and by comparing it with the half-wrapped tray (HWT). MATERIALS AND METHODS: An intraoral scanner was used to acquire data on the maxillary dental arch of a patient with periodontitis.Furthermore, 20 maxillary dental arch models were 3D printed. Using 3Shape, PlastyCAD software, and 3D printing technology, 10 FTMC (method I) and HWT (method II) were obtained. By preoperative preparation, intraoperative coordination, and postoperative measurement, the brackets were transferred from the trays to the 3D-printed maxillary dental arch models. Additionally, the bracket's excess adhesive as well as linear and angular deviations were measured, and the differences between the two methods were analyzed. RESULTS: Excess adhesive was observed in both methods, with FTMC showing less adhesive (P< 0.001), with a statistical difference. Furthermore, HWT's vertical, tip and torque, which was significantly greater than FTMC (P< 0.05), with no statistical difference among other respects. The study data of incisors, canines, and premolars, showed that the premolars had more adhesive residue and were more likely to have linear and angular deviations. CONCLUSIONS: The FTMC had higher bracket bonding effect in comparison to HWT, and the adhesive residue, linear and angular deviations are smaller. The fence tray offers an intuitive view of the precise bonding of the bracket, and can remove excess adhesive to prevent white spot lesions via care, providing a different bonding method for clinical applications.


Asunto(s)
Recubrimiento Dental Adhesivo , Soportes Ortodóncicos , Humanos , Recubrimiento Dental Adhesivo/métodos , Técnicas In Vitro , Modelos Dentales , Adhesivos , Impresión Tridimensional , Cementos Dentales , Arco Dental
14.
Cureus ; 16(3): e56382, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38633932

RESUMEN

Trauma, cancer, and congenital defects may all result in the loss of an eye. This leads to significant emotional and physical challenges in an individual's life. In such cases, cautious preoperative, surgical, and prosthetic planning employing a multidisciplinary approach is essential for effective rehabilitation. Iris positioning is one of the crucial steps in the fabrication of a customized ocular prosthesis. Iris positioning is a technique-sensitive process, hence visual evaluation by itself could not provide reliable results. This case report illustrates a method of iris disk positioning on a custom-made ocular prosthesis using an adjustable trial frame. The advantage of the adjustable mechanism of the adjustable trial frame was utilized here to position the iris on the scleral blank. Since the iris disk on the ocular prosthesis was positioned in symmetry with that of the natural eye, the patient's aesthetics were restored.

15.
J Prosthodont ; 2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38513226

RESUMEN

This technique presents a new fabrication workflow for a three-dimensional (3D) printed custom tray, which duplicates the morphology of the treatment denture for maxillofacial prostheses using an intraoral scanner, computer-aided design (CAD) software, and a 3D printer. A 70-year-old man underwent reconstruction of segmental mandibulectomy for mandibular osteoblastoma, followed by implant placement and secondary surgery. During the surgical treatment, a treatment denture was fabricated to restore oral function and determine the morphology of the definitive denture. To create the definitive denture with the same morphology as the treatment denture a custom tray was fabricated with the denture morphology after chairside adjustments. The oral cavity was scanned using an intraoral scanner, and the data acquired were imported into general-purpose CAD software, adjusted, and imported into a 3D printer to produce the custom tray. This was fitted into the patient's mouth without any issues, and closed tray impressions were made with impression caps for the locator attachments on the implant body. The morphology of the treatment denture was replicated in the definitive denture by making a silicon impression of the cameo surface at the fabrication of the cast after impression making. In this technique, the morphology of the treatment denture was transferred accurately to the definitive implant partial denture by leveraging existing digital technology. This method represents a practical approach for partial denture fabrication, including maxillofacial defects with complex denture configurations.

16.
Heliyon ; 10(2): e24623, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38298662

RESUMEN

In this study, the drying of oyster mushrooms (P. ostreatus) in a tray dryer was optimized. The parameters used to optimize the drying process were drying temperature, airspeed, mass loading, and moisture content. Its drying kinetics were investigated at the optimum drying parameters. A quadratic equation was obtained to predict the moisture content of mushrooms at the given drying temperature, airspeed, and mass loading, and it was validated against experimental results. A minimum moisture content (9.99 wt%) was obtained at the optimum conditions of 60 °C, 3 m/s airspeed, and mass loading of 200 g using a tray dryer. Proximate analysis, shelf-life analysis, inorganic elemental analysis, and functional group analysis were done as a characterization method for mushrooms after drying at the optimum drying conditions. About 27.8 wt% protein and 50.2 wt% carbohydrates were found in proximate results. Besides, potassium and sodium were the dominant elements as estimated by spectrophotometry analysis. The induction period (IP) of dried mushrooms at room temperature is 3520:47 (hour: minute) from the oxidation stability analysis, and the water activity of dried mushrooms was found to be 0.36. The drying kinetics of oyster mushrooms were studied at various temperatures (50-75 °C), optimum airspeed (3 m/s), and mass loading (200 g). The best-fit model describing the mushrooms drying kinetics was found to be Midilli et al., with the lowest RMSE (0.008749), X2 (0.0014), and the highest R2(0.9993) values. The kinetic triplet activation energy, effective diffusivity, and diffusivity constant (Ea, Deff, D0) for oyster mushrooms drying were determined and found to lay in the general range for foodstuffs. The value of Deff results lies within the range of 10-8 to 10-12 m2/s, with Ea of 15.32 kJ/mol and D0 value 2.263 × 10-6 m2/s.

17.
J Orofac Orthop ; 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38411719

RESUMEN

PURPOSE: The aim was to investigate the influence of three different three-dimensional (3D)-printed bonding tray designs and professional experience on accuracy of indirect bracket placement. METHODS: Virtual bracket placement was performed on a scanned dental model using OnyxCeph software (Image Instruments, Chemnitz, Germany). Three different designs for indirect bonding trays (open, semi-open, and closed design) were created and produced using a 3D printer. To analyze the influence of professional experience, one of the three tray designs was produced twice. In this case, bracket placement was performed by an inexperienced dentist. Bracket positions were scanned after the indirect bonding procedure. Linear and angular transfer errors were measured. Significant differences between the target and actual situation were analyzed using the Kruskal-Wallis and χ2 test. RESULTS: All bonding tray designs resulted in comparable results. The results of the unexperienced dentist showed significantly higher deviations than those for the experienced orthodontist in the torque direction. However, the mean values were comparable. The open tray design exceeded the clinically acceptable limits of 0.25 mm and 1° more often. The inexperienced dentist exceeded these limits significantly more often than the experienced orthodontist in the vertical and torque direction. The immediate bracket loss rate showed no significant differences between the different tray designs. Significantly more bracket losses were observed for the inexperienced dentist during the procedure compared to the experienced orthodontist. CONCLUSIONS: The bonding tray design and professional experience had an influence on the exceedance of clinically relevant limits of positioning accuracy and on the bracket loss rate.

18.
J Mech Behav Biomed Mater ; 151: 106347, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38181568

RESUMEN

Primary stability, the mechanical fixation between implant and bone prior to osseointegration, is crucial for the long-term success of cementless tibial trays. However, little is known about the mechanical interplay between the implant and bone internally, as experimental studies quantifying internal strain are limited. This study employed digital volume correlation (DVC) to quantify the immediate post-implantation strain field of five cadaveric tibiae implanted with a commercially available cementless titanium tibial tray (Attune, DePuy Synthes). The tibiae were subjected to a five-step loading sequence (0-2.5 bodyweight, BW) replicating stair descent, with concomitant time-elapsed micro-CT imaging. With progressive loads, increased compression of trabecular bone was quantified, with the highest strains directly under the posterior region of the tibial tray implant, dissipating with increasing distance from the bone-implant interface. After load removal of the last load step (2.5BW), residual strains were observed in all of the five tibiae, with residual strains confined within 3.14 mm from the bone-implant interface. The residual strain is reflective of the observed initial migration of cementless tibial trays reported in clinical studies. The presence of strains above the yield strain of bone accepted in literature suggests that inelastic properties should be included within finite element models of the initial mechanical environment. This study provides a means to experimentally quantify the internal strain distribution of human tibia with cementless trays, increasing the understanding of the mechanical interaction between bone and implant.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Tibia , Humanos , Tibia/diagnóstico por imagen , Tibia/cirugía , Microtomografía por Rayos X , Interfase Hueso-Implante , Cadáver
19.
Knee ; 47: 1-12, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38171206

RESUMEN

BACKGROUND: We investigated the relationship between the backside deformation of polyethylene (PE) tibial inserts and aseptic loosening of the Option stemmed tibial tray used with Zimmer NexGen posterior-stabilised (PS) devices. We hypothesized that explanted inserts used in PS designs would exhibit greater extents of PE backside deformation than those used in equivalent cruciate retaining (CR) designs and that PE inserts retrieved from total knee arthroplasties (TKAs) revised for aseptic tibial tray loosening would exhibit greater extents of backside deformation than TKAs revised for other reasons. METHODS: A total of 73 explanted fixed-bearing TKAs (42 CR and 31 PS) were examined. PE components underwent geometric examination with a coordinate measuring machine using validated techniques. Multiple regression modelling was used to identify variables associated with revision secondary to aseptic loosing and to determine factors associated with increased PE backside deformation. RESULTS: PE inserts retrieved from TKAs with aseptic loosening had significantly greater backside deformation than those retrieved from TKAs revised for other reasons (p < 0.001). Greater PE backside deformation was significantly associated with larger tray/insert clearance heights (p < 0.001), thinner inserts (p < 0.001) and PS TKAs (p = 0.001). CONCLUSION: PE backside deformation was significantly greater in the PS TKAs. This may provide one explanation for the increased rate of aseptic loosening reported with the Option tibial tray used with the Legacy Posterior Stabilised (LPS) system.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Prótesis de la Rodilla , Polietileno , Diseño de Prótesis , Falla de Prótesis , Humanos , Artroplastia de Reemplazo de Rodilla/instrumentación , Femenino , Anciano , Masculino , Reoperación , Persona de Mediana Edad , Tibia/cirugía , Anciano de 80 o más Años
20.
J Prosthodont ; 33(4): 307-312, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37927117

RESUMEN

Microstomia presents a challenge for the patient and dental provider. This report describes a partial digital workflow for the fabrication of a mandibular complete denture for a patient with microstomia. Computer-aided design and computer-aided manufacturing technology was utilized to 3D print a sectional custom tray with a unique design. The sectional custom tray was used to make a conventional border molded impression of the edentulous arch to fabricate a flexible complete mandibular denture for a 58-year-old female patient with scleroderma and microstomia. This treatment resulted in a successful prosthetic outcome and high patient satisfaction.


Asunto(s)
Microstomía , Boca Edéntula , Femenino , Humanos , Persona de Mediana Edad , Diseño de Dentadura , Microstomía/complicaciones , Técnica de Impresión Dental , Dentadura Completa , Diseño Asistido por Computadora
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