A. If only one of your teeth is shorter and you haven’t traumatised it it any way it may be caused by a bite problem. If your lower teeth are crowded there may be one that is more prominent than the others and this may be grinding over the upper tooth during chewing.
A veneer is always better for the tooth as it is less destructive but only if the preparation stays within enamel. Before you have it done, if there are any bite problems these need to be sorted out first otherwise your veneer will break
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