How is the prognosis of central incisor with a preapical abcess , that ch passes beyound its apex?will the ch be absorbed?will the abcess heal?

Varies: Unfortunately, we can't give you a definitive answer or a specific number on the prognosis of your issue. There are too many variables and no one can accurately determine what will happen in your specific circumstances. Abscesses do heal, and the ch can resorb, although that is not necessary for success. Make sure you are in the hands of a competent endodontist and have him\her monitor it.

Hard to say: Even the most perfectly obturated teeth can fail, and others that don't seem to be filled adequately never give the patient a problem. As suggested, have your dentist (endodontist) monitor the tooth for any sign of problems.