After my wisdom teeth extractions. will eating yogurt help the yeast infection?

Unlikely: Yeast infection from wisdom tooth extraction is pretty uncommon. It's more often caused by being on an antibiotic (usually vaginal yeast infection). Probiotics such as acidophilus can help with this. For oral yeast infections (candidiasis), a prescription rinse such as Nystatin is usually best.

Yes: Yeast infections are more like yeast imbalances. The yeast is normally in balance with resident bacteria. When something throws off the balance the yeast can over populate and you have symptoms. Yogurt helps replenish some of the normal bacteria if the yogurt has active cultures. If it's not active cultures there is still a benificial affect from the yogurt while the bacterial balance returns.