The Influence of the Attachment Type and Implant Number Supporting Mandibular Overdentures on Stress Distribution

Abstract

It may be concluded that in cases with low quality and quantity of bone, the increase in number of implants and the use of a splinted attachment should be preferred to reduce forces emerging around the implants during function. The use of 2 single attachments in cases with good bone quality and ideal size implants still seems to be a safe and sufficient solution for the treatment of mandibular edentulism with OVDs.

Effect of implant- and occlusal load location on stress distribution in Locator attachments of mandibular overdenture. A finite element study

“… 41 42 43 Also, since contacts between all teeth are established during mastication and an overdenture could combine straight and angled implants or abutments, a solely vertical load design of unilateral or bilateral posterior location may be a limitation that the clinician should consider when comparing and discussing the clinical implications of a finite element analysis. Although unilateral and bilateral occlusal load combinations are cited in some studies, 9 16 23 28 55 the dental literature concerning overdenture and finite element analysis reports a great variability in the direction, application site, and magnitude of occlusal loads, which per se is a limitation for the comparison of results; it is therefore necessary to standardize these factors.…”

“… 12 13 14 In addition, numerous clinical and biomechanical studies have found differences when assessing and comparing the use of stud, ball, and bar attachments in terms of different parameters, including retention strength, resilience, progressive retention loss, and replacement/activation of attachment retention inserts and periimplant bone stress. 15 16 17 18 19 20 21 22 23 Meanwhile, although the degree of patient satisfaction does not seem to depend on the attachment retention system of the overdenture, 13 24 25 Locator® attachment is a stud, self-aligning attachment system, widely used for its simplicity of use, variable retention capacity, resilient retention, and compensation of implant disparallelism. However, like other attachments, it is not free from mechanical complications associated with the loosening/fracturing of the screw and premature change of the insert plastic patrix due to retention loss.…”

Strain characteristics of Marburg double crown-retained implant overdentures compared with bar and ball-retained implant overdentures, with and without a rigid major connector

“…[3][4][5][6][7] Strain gauge (SG) analysis is a commonly used method in dentistry for the biomechanical evaluation of stress distribution in vivo 8,9 and in vitro. [10][11][12][13][14] However, the validation of biomechanical strain measurements and calculated stress values is important in gaining reliable results. The information obtained from SG under differing experimental conditions should be regarded skeptically before clinical interpretation and prediction because these measurements are limited to the area where the gauge is bonded 11 or embedded in resin.…”

“…[10][11][12][13][14] However, the validation of biomechanical strain measurements and calculated stress values is important in gaining reliable results. The information obtained from SG under differing experimental conditions should be regarded skeptically before clinical interpretation and prediction because these measurements are limited to the area where the gauge is bonded 11 or embedded in resin. 10,14 Various retentive mechanisms are available for attaching an overdenture to implants.…”

“…The SGs used in the current study were embedded in an acrylic resin model 10,14 instead of being bonded to the surfaces 11 The rosette-type SGs used in the present study were placed on the distal aspects of implants where the stress transmitted from the overdentures is critical and where alveolar bone loss is possible because of the intensity and duration of the transmitted stress. These locations of the SGs were consistent with the bilateral loading protocol.…”