Abstract
On the model, in the five cases of missing central incisors or lateral incisors, I picked some teeth in various combinations as abutment teeth, analyzed movement of the loaded bridges, compared each capacity to load and got the following conclusion:
1. The load-capacity index that was in proportion to the capacity of bridges to load was gotten.
2. The relation between load-capacity index and suitability of bridges was examined from the three-dimensional movement of bridges and got the following criteria:
1) load-capacity inde≥20: suitable for bridge
2) load-capacity index 13∼19: border area
suitable for the bridge that abutment teeth at the both sides of missing teeth have balancedresistance
not suitable for the bridge that abutment teeth at the both sides of missing teeth have unbalanced resistance
3) load-capacity index≤12: not suitable for bridge
3. Considering the load-capacity index and the three-dimensional movement of bridges, suitable designs of bridges are following:(1) |1 (2), (3)(2) 1|1 (2)(3), (1) |12 (3), (3)(2) 1|12 (3)(4), (3) 1|12 (3)(4)
