ASSESSMENT OF STRESS DISTRIBUTION USING EQUATOR ATTACHMENT DESIGN IN MANDIBULAR IMPLANT-RETAINED OVERDENTURES IN COMPARISON WITH BALL AND SOCKET ATTACHMENT DESIGN:3D FINITE ELEMENT ANALYSIS

Abstract

Although treatment with conventional complete dentures has long been the treatment of choice in the oral rehabilitation of edentulous patients, these individuals have reported several complaints involving difficulties of adaptation, most of which have been associated with mandibular complete dentures and which include lack of retention and stability, chewing difficulties, low self-esteem, and reduced quality of life and satisfaction [1]. Today, implant-supported mandibular overdentures retained by two implants associated with a maxillary complete denture have been proposed as the first choice of treatment for edentulous patients [2] . This treatment seeks to provide better stability and retention of the mandibular complete denture, thus improving masticatory function of the patient and providing greater satisfaction, better oral health-related quality of life, and comfort [3] . Attachments can be used as retention mechanisms and can be classified as splinted systems (bar attachment) or unsplinted systems (o-ring/ball/spherical types, magnets, telescopic crowns or stud attachments). The select attachments for implant supported overdentures should have enough retentive properties to enhance the stability of the prosthesis The way stress is applied to implants after osseointegration was one of the first factors considered and studied in implant dentistry. Therefore, the selected attachment used in implant retained overdenture has a potential effect on implant survival rate, marginal bone loss, soft tissue complications, retention, stress distribution, maintenance complications and patient's satisfaction [4] .

The distribution of forces in peri-implant bone has been investigated by finite element analyses in several studies. Recently, stress distribution in bone correlated with implant-supported prosthesis design has been investigated primarily by means of two-dimensional (2D) and three-dimensional (3D) finite element analyses (FEAs). Studies comparing the accuracy of these analyses found that, if detailed stress information is required, then 3D modeling is necessary.