- Presence of active signs or symptoms of acute infection in the tooth or the remaining root Heavy smokers (more than 2 packs per day) Parafunctional habits (clenching or bruxism) diagnosed by history taking and observation of the occlusal surface of the posterior teeth for wear facets Patients with poor oral hygiene Pregnant women Any systemic condition that may interfere with osseointegration (as uncontrolled diabetes, recent head and neck radiation) Severe overeruption of the opposing teeth to avoid any premature contact with the temporary crown during the osseointegration period.