Support Ratio Between Abutment and Soft Tissue Under Overdentures: A Comparison Between Use of Two and Four Abutments.
The purpose of this preliminary in vivo study was to compare force distribution on abutments (tooth or implant) and tissues supporting overdentures with two or four abutments.



A convenience sample of five subjects with tooth and/or implant-supported overdentures was enrolled. Recordings were completed on each subject using a force-measuring system mounted on a metal framework with four anteroposterior spread abutments (A), four abutments with denture bases (B), and on two anterior abutments with denture bases (C). The tissue-support ratio (TSR) was calculated as (A-B)/A or (A-C)/A.



TSR values changed 1.5 to 2 times when the number of abutments was reduced from four to two.



The amount of tissue strain on the posterior residual ridge increased when the number of abutments was reduced.
Manami
M
Abe
Tsung-Chieh
TC
Yang
Yoshionobu
Y
Maeda
Takanori
T
Ando
Masahiro
M
Wada
D000368:Aged; D059605:Dental Implant-Abutment Design; D019094:Dental Prosthesis, Implant-Supported; D003799:Dental Stress Analysis; D003779:Denture Design; D003828:Denture, Overlay; D005260:Female; D006801:Humans; D008297:Male