Search results for "orthodontics"
showing 8 items of 928 documents
Two different posterior-stabilized mobile-bearing TKA designs: navigator evaluation of intraoperative kinematic differences
2020
Purpose: The purpose of this study was to compare two types of posterior-stabilized (PS) mobile-bearing (MB) total knee arthroplasties (TKAs). The hypothesis was that no major differences were going to be found among the two TKA designs. Methods: Two cohorts of patients who were divided according to implant design (Cohort A, new design gradually reducing radius PS MB TKA; Cohort B, traditional dual-radius PS MB TKA) were analyzed by means of intraoperative navigation. All operations were guided by a non-image-based navigation system that recorded relative femoral and tibial positions in native and implanted knees during the following kinematic tests: passive range of motion (PROM), varus–va…
Kinematics and kinetics analysis of midfoot joints of 30 normal subjects during walking
2016
Abstract Introduction There is not enough evidence in form of clinical studies regarding the behavior of the midfoot joints in dynamic situations such us walking or running. The present work aims to study the mechanical behavior of midfoot joints with a multisegmented foot model with special interest in joint moments and their clinical significance. Subjects and methods A computerized 3-dimensional gait study was performed on healthy male adult subjects with a neutral Foot Posture Index (FPI) (from 0 to +5) during walking. Joint angle and external moments were estimated with a multisegment foot model that considers three separate segments (forefoot, rearfoot and hallux) and graphs and value…
The effect of cement fixation on initial micromotion of the femoral component in condylar knee replacement
1992
Four fresh, cadaveric specimens were fitted with total knee replacements and mounted on a knee joint loading and measuring rig. Femoral component micromotion in the sagittal plane was measured with a transducer during flexion and extension of the specimen. Various condylar designs were used without and with cement. Movement followed a characteristic curve pattern and was less with cement fixation particularly for bone of low trabecular strength as determined by bone sample tests for stiffness. Cement fixation appears to be superior to cementless fixation.
Comparison of Postoperative Coronal Leg Alignment in Customized Individually Made and Conventional Total Knee Arthroplasty
2021
Neutral coronal leg alignment is known to be important for postoperative outcome in total knee arthroplasty (TKA). Customized individually made implants (CIM) instrumented with patient-specific cutting guides are an innovation aiming to increase the precision and reliability of implant positioning and reconstruction of leg alignment. We aimed to compare reconstruction of the hip–knee–ankle angle (HKA) of the novel CIM system iTotal™ CR G2 (ConforMIS Inc.) to a matched cohort of the off-the-shelf (OTS) knee replacement system Vanguard™ CR (Zimmer Biomet). Retrospective analysis of postoperative coronal full-leg weight-bearing radiographs of 562 TKA (283 CIM TKA, 279 OTS TKA) was conducted. V…
In Vitro Study on Bone Heating during Drilling of the Implant Site: Material, Design and Wear of the Surgical Drill
2020
Objective: An in vitro study was made to compare mean thermal variation according to the material, design and wear of the surgical drills used during dental implant site preparation. Material and methods: Three study groups (stainless steel drills with straight blades
Diseño y puesta a punto de un método cefalométrico en 3D para el estudio de la población ortodóncica
2011
Introducción: La introducción de la tomografía computarizada de haz cónico (CBCT) y su aplicación clínica a la imagen craneofacial tridimensional (3D) supone una herramienta diagnóstica esencial para el clínico. Objetivos: 1-Evaluar la reproducibilidad en la localización de puntos cefalométricos pertenecientes a tejidos duros del cráneo sobre imágenes escaneadas con un equipo CBCT 2-Comprobar si los valores de diferentes mediciones de las reconstrucciones 3D del CBCT se pueden comparar a las mediciones realizadas sobre imágenes 2D de la telerradiografía lateral de cráneo y comparar también si existen diferencias entre dos tipos diferentes de software de CBCT. 3-Diseñar un método cefalométri…
Clinical assessment and comparison of ACL reconstruction using synthetic graft (Neoligaments versus FiberTape).
2021
Background Due to the low potential for primary biological healing of the anterior cruciate ligament (ACL), the most popular approach is currently reconstruction using a graft. Recent research indicates that the technique of strengthening a damaged ligament with synthetic tapes (internal bracing) may be an alternative to reconstructive treatment, especially in cases of partial ACL damage. Objectives To compare and evaluate the possibility of using a synthetic graft (Neoligaments or FiberTape) to treat partial lesions of the ACL. Material and methods This was a retrospective cohort study. Selected from a pool of 128 patients undergoing primary unilateral intra-articular ACL reconstruction du…
Evaluation of alveolar cortical bone thickness and density for orthodontic mini-implant placement.
2013
Objective: Mini-implant stability is primarily related to bone quality and quantity. This study evaluated alveolar cortical bone thickness and density differences between interradicular sites at different levels from the alveolar crest, and assessed the differences between adolescents (12-18 years of age) and adults (19-50 years of age), males and females, upper and lower arch, anterior and posterior region of jaws and buccal and oral side. Study Design: In this retrospective study, 48 Computed Tomography scans, performed for oral surgery purposes were selected from dental records of 3,223 Caucasian orthodontic patients. The SimPlant software (Materialise, Leuven, Belgium) was used to measu…