t is important the strings be replaced one by one otherwise it can happen that the bridge collapses and a trip to a violin maker becomes necessary. After each rising of a string, the bridge should be checked. It should be slightly inclined toward the tailpiece and its feet should have a perfect fit. If this is not the case take the bridge carefully between your thumbs and use pressure to firmly correct its position.

Have a violinmaker show you this procedure. The proper position has great influence on the sound. A description of how a bridge is shaped can be found here.