ABSTRACT
The distribution and action of forces transmitted to the supporting tissue through com- ponents of the denture are related to denture design and material property.The studies of the effects of partial denture clasp design on the movement of abutthent teeth have been reported internally and abroad in many articles.But the studies of the effect of major connectors de- sign on the movement of abutment teeth have less reported. The present study has been carried out using double-exposure holography to measure the movement of abutment on Kennedy's Class I model. The dentures were different in major connector design.The artificial forces were designed in vertical,buccal and lingual direc tions.The results showed that linguoplate could widely distribute forces and the resistance to lateral forces was good,however,the lingual bar was not so good as the linguoplate.The plastic base connector could not distribute forces effectively and the abutiment tooth movement.Therefore it suggested that this kind of connector not be used. The method used in this study is sensitive and non-invasive.It can measure the tooth movement in three-dimensions.The repetition is good in the same condition.