			Home About us Contact

Implants Used (implant + used)

Distribution by Scientific Domains

Medical Sciences	100%

Selected Abstracts

Effects of splinted prosthesis supported a wide implant or two implants: a three-dimensional finite element analysis

CLINICAL ORAL IMPLANTS RESEARCH, Issue 4 2005
Heng-Li Huang
Abstract Objectives: Three-dimensional finite element (FE) models of splinted prosthetic crowns were studied and stress analyses were evaluated with different types of implant support, including standard, wide or two implant(s) for partial, posterior edentulous restorations. Material and methods: The FE models were constructed based on a cadaver mandible containing the 2nd premolar and the 1st molar. The crowns of these two teeth were modeled as connected and disconnected to mimic the splinted and non-splinted designs, respectively. One standard implant was placed at the premolar region, while three types of implant support, one at a time (the standard implant, wide implant and two implants), were used to support the molar crown. A 100 N oblique load was applied to the buccal cusp on each crown. The FE simulation was validated experimentally via strain gauge measurement. Results: The experimental data were well correlated with the FE predictions (r2=0.97). When compared with the standard implant used in the molar area, the wide implant and two implants reduced the peak stress in crestal bone by 29,37% for both splinted and non-splinted cases. Inserting the standard implant into both the premolar and molar area, the bone stresses were identical for splinted and non-splinted designs. However, splinting the adjacent crowns has shown to decrease the bone stresses at the premolar region by 25%, while the wide implant or two implants were placed at the molar region. Conclusion: The biomechanical advantages of using the wide implant or two implants are almost identical. The benefit of load sharing by the splinted crowns is notable only when the implants on the premolar and molar regions have different supporting ability. Résumé Des modèles d'éléments finis (FE) tridimensionnels de couronnes prothétiques attachés ont étéétudiés et les analyses de stress ont étéévalués avec différents types de support d'implants comprenant le standard, le large ou deux implants pour des restaurations postérieures partielles. Les modèles FE ont été construits sur base de mandibule de cadavre contenant deux prémolaires et une molaire. Les couronnes de ces deux dents ont été modelées comme connectées et non-connectées pour mimer respectivement les modèles avec attache ou sans. Un implant standard a été placé dans la région prémolaire tandis que trois types d'implants supportaient en un temps (l'implant standard, l'implant large et deux implants) ont été utilisés pour porter la couronne molaire. Une charge oblique de 100 N a été appliquée sur la cuspide vestibulaire de chaque couronne. La simulation FE a été validée expérimentalement via une mesure par jauge de force. Les données expérimentales étaient en bonne corrélation avec les prévisions FE (r2=0,97). Comparés à l'implant standard utilisé dans la zone molaire, l'implant large et la combinaison de deux implants réduisait le pic de stress dans l'os crestal de 29 à 37% tant dans les cas attachés que non-attachés. En insérant l'implant standard dans la zone prémolaire et molaire, le stress osseux était identique pour les modèles attachés et non-attachés. Cependant, l'attache reliant les couronnes adjacentes s'accompagnait d'une dimininution des stress osseux dans la région prémolaire de 25%, tandis que l'implant large ou les deux implants étaient placés dans la région molaire. Les avantages biomécaniques de l'utilisation d'un implant large ou de deux implants sont quasi identiques. Le bénéfice d'une charge partagée par les couronnes solidarisées n'est visible que lorsque les implants des régions prémolaires et molaires ont des capacités de support différentes. Zusammenfassung Ziel: Bei der Rekonstruktion von Lücken im hinteren Seitenzahnbereich untersuchte man in einem dreidimensionalen Finiteelement-Modell (FE) zementierte Kronen und wertete in Belastungs-Analysen verschiedene Implantatabstützungen aus, nämlich auf Standardimplantaten, Wide neck-Implantaten oder auf zwei Implantaten. Material und Methoden: Das FE-Modell basierte auf den Werten eines Leichenunterkiefers in der Region des zweiten Prämolaren und ersten Molaren. Die Kronen auf diesen beiden Zähne wurden jeweils zusammenhängend und einzeln modelliert, so dass man die verblockte und unverblockte Situation nachempfinden konnte. In der Prämolarenregion implantierte man ein Standartimplantat. In der Molarenregion wählte man jeweils eine von drei verschiedenen Varianten der Abstützung für die Kronen: ein Standardimplantat, ein Wide neck-Implantat oder zwei Implantate. Auf den buccalen Höcker jeder Krone liess man schräg eine Kraft von 100 N auftreffen. Die FE-Simulation eichte man experimentell mit Hilfe von Dehnmessstreifen. Resultate: Die experimentellen Daten korrelierten sehr gut mit den FE-Voraussagen (r2=0.97). Verglich man die in der Molarenregion verwendeten Standartimplantate mit den Wide neck-Implantaten und zwei Implantaten, so reduzierte sich die Spitzenbelastung im crestalen Knochen um 29,37%, bei den verblockten wie auch bei den unverblockten Versionen. Setzte man sowohl im Prämolaren wie auch im Molarengebiet Standardimplantate, so war die Knochenbelastung für die verblockte wie auch für die unverblockte Version gleich gross. Wenn aber das Wide neck-Implantat oder zwei Implantate in der Molarenregion gesetzt worden waren, so vermochte die Verblockung der Implantat-Kronen die Knochenbelastung in der Prämolarenregion um 25% zu senken. Zusammenfassung: Ob man das Wide neck-Implantat oder zwei Implantate verwendet, die biomechanischen Vorteile sind beinahe identisch. Man erreicht durch das Verblocken von Kronen erst dann einen spürbaren Vorteil bezüglich Lastenverteilung, wenn die Implantate in der Prämolaren- und Molarenregion verschiedene Tragfähigkeiten aufweisen. Resumen Objetivos: Se estudiaron modelos tridimensionales de elementos finitos (FE) de coronas protésicas y se evaluó el análisis de estrés con diferentes tipos de soporte implantario, incluyendo implantes estándar, anchos o dos implantes, para restauraciones parciales en posteriores edéntulos. Material y métodos: Se construyeron dos modelos FE basados en mandíbula de cadáver conteniendo el 2° premolar y el 1er molar. Las coronas de estos dos dientes se modelaron como conectadas y desconectadas para imitar los diseños conectados y desconectados, respectivamente. Se colocó un implante estándar en la región premolar, mientras que para soportar la corona molar se colocaron tres tipos de implantes, uno a la vez, (un implante estándar, un implante ancho y dos implantes). Se aplicó una carga oblicua de 100N en la cúspide bucal de cada corona. La simulación de elementos finitos se validó experimentalmente por medio de medición de tensión. Resultados: Los datos experimentales se correlacionaron bien con las predicciones FE (r2=0.97). Al comparase a los implantes estándar usados en el área molar, el implante ancho y dos implantes redujeron el pico de estrés en el hueso crestal en un 29,37% tanto para los caso ferulizados como para los no ferulizados. Al insertar el implante estándar tanto en la región premolar como en la molar, los estrés óseos fueron idénticos para los diseños ferulizados como para los no ferulizados. De todos modos, la ferulización de las coronas adyacentes mostró un descenso del estrés óseo en un 25%, mientras el implante ancho o los dos implantes se colocaron en la región molar. Conclusión: Las ventajas biomecánicas de usar el implante ancho o dos implantes fueron casi idénticas. El beneficio de compartir la carga al ferulizar las coronas es notable solo cuando los implantes en las regiones premolar y molar tienen diferente capacidad de soporte. [source]

Health service costs in Europe: cost and reimbursement of primary hip replacement in nine countries

HEALTH ECONOMICS, Issue S1 2008
Tom Stargardt
Abstract This paper assesses variations in the cost of primary hip replacement between and within nine member states of the European Union (EU). It also compares the cost of service with public-payer reimbursements. To do so, data on cost and reimbursement were surveyed at the micro-level in 42 hospitals in Denmark, England, France, Germany, Hungary, Italy, The Netherlands, Poland, and Spain. The total cost of treatment ranged from ,1290 (Hungary) to ,8739 (The Netherlands), with a mean cost of ,5043 (STD±,2071). The main cost drivers were found to be implants (34% of total cost on average) and ward costs (20.9% of total cost on average). A one-way random effects analysis of variance model indicated that 74.0% of variation was between and only 26% of variation was within countries. In a two-level random-intercept regression model, purchasing-power parities explained 79.4% of the explainable between-country variation, while the percentage of uncemented implants used and the number of beds explained 12.1 and 1.6% of explainable within-country variation, respectively. The large differences in cost and reimbursement between Poland, Hungary, and the other EU member states shows that primary total hip replacement is a highly relevant case for cross-border care. Copyright © 2008 John Wiley & Sons, Ltd. [source]

The Milled Bar-Retained Removable Bridge Implant-Supported Prosthesis: A Treatment Alternative for the Edentulous Maxilla

JOURNAL OF ESTHETIC AND RESTORATIVE DENTISTRY, Issue 4 2002
DGDP(UK), PAUL A. TIPTON BDS
ABSTRACT Restoration of the edentulous jaw with dental implants can be achieved using either an implant-supported prosthesis, such as a fixed bridge, or an implant-retained prosthesis, such as a traditional overdenture. The implant-retained prostheses use edentulous ridges as primary stress-bearing regions, and through stress-breaking mechanisms, the implants are not loaded during function. However, the success rates of maxillary overdentures do not appear to be as good as for mandibular overdentures; this may be attributable to the adverse loading conditions, short implant length, poor quality of bone, number of implants used, flexible bar design, or poor treatment planning. Many articles have also described the numerous problems and multiple visits required in maintaining a traditional bar-retained overdenture restoration, often making it more expensive in the long term than a fixed restoration. The milled bar implant-supported prosthesis offers the benefits of both fixed and removable restorations. Its infrastructure provides the same rigidity as the fixed restoration, owing to the precise fit to the superstructure, which is removable, to promote adequate access for hygiene, yet it still provides lip support and maintains close contact with the soft tissues. These advantages enhance phonetics, esthetics, correct lip support, maintenance, and patient comfort. CLINICAL SIGNIFICANCE Restoring esthetics and function for the edentulous patient requires a multidiscipline approach for success. This article discusses the techniques for restoring function and esthetics for these patients, using a milled bar restoration supported and retained by dental implants. [source]

Short Implants Placed One-Stage in Maxillae and Mandibles: A Retrospective Clinical Study with 1 to 9 Years of Follow-Up

CLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 1 2007
Paulo Maló DDS
ABSTRACT Background:, The use of short implants (7,8.5 mm) has historically been associated with lower survival rates than for longer implants. However, recent clinical studies indicate that short implants may support most prosthetic restorations quite adequately, but still clinical documentation is sparse. Purpose:, The purpose of this study was to report on the placement of short Brånemark implants, testing the hypothesis that short implants in atrophied jaws might give similar long-term implant survival rates as longer implants used in larger bone volumes. Materials and Methods:, This retrospective clinical study included 237 consecutively treated patients with 408 short Brånemark implants supporting 151 fixed prostheses. One hundred thirty-one of the implants were 7-mm long, and 277 were 8.5-mm long. Final abutments were delivered at the time of surgery, and final prostheses were delivered 4 to 6 months later. Results:, One hundred and twenty six of the 7-mm implants (96%) have passed the 1-year follow-up; 110 (84%), the 2-year follow-up; and 88 (67%), the 5-year follow-up. Five implants failed in four patients before the 6-month follow-up, giving a cumulative survival rate of 96.2% at 5 years. The average bone resorption was 1 mm (SD=0.6 mm) after the first year and 1.8 mm (SD=0.8 mm) after the fifth year of function. Two hundred sixty nine of the 8.5-mm implants (97%) have passed the 1-year follow-up; 220 (79%), the 2-year follow-up; and 142 (51%), the 5-year follow-up. Eight implants failed in seven patients before the 6-month follow-up, giving a cumulative survival rate of 97.1% at 5 years. The average bone resorption was 1.3 mm (SD=0.8 mm) after the first year and 2.2 mm (SD=0.9 mm) after the fifth year of function. Conclusions:, The cumulative survival rates of 96.2 and 97.1% at 5 years for implants of 7.0- and 8.5-mm length, respectively, indicate that one-stage short Brånemark implants used in both jaws is a viable concept. [source]