Open bite with new fix bridge. Is it causing me to mispronounce words? (Photo)

An open bite is a result of a temporomandibular joint problem whether there's a bridge there or not.  The best way to diagnose that problem is to have a specialized MRI of your jaw joints.

Going from removable dentures to fixed bridges or the other way as well can often create temporary speech irregularities since your tongue was used to the previous situation. In almost all cases the speech returns to its previous format once the tongue re-adjusts.  However you mentioned that your bite was opened. If this was unintentional you must report it to your dentist immediately.  Even if it was planned you should call the office and request a consultation with the dentist. He/she may want to do some bite adjustments based on close assessment.