The rapid increase and final burst in the expansion of dough once it is loaded into the oven. The expansion ceases as soon as the dough temperature reaches about 140° F when the yeast dies.
There are many factors that influence the degree and quality of the oven spring when baking bread: overall dough quality, the amount of yeast in the dough, the degree of fermentation (it should not be under fermented or over fermented), and oven temperature. The method of baking, that is, whether using a pan, stone/tiles, or tin will also be a factor.
Added by: shipton-mill