To elicit information about the phenomenon of intrusion of natural tooth abutments in implant-connected prostheses, a survey was distributed to clinicians with varied experience. Although practitioners with more experience in fabricating implant-supported dentures connected to natural teeth reported fewer instances of intrusion, it cannot be concluded that this observation is significant. The cause of intrusion is probably multifactorial, and respondents suggested several possible causative factors: disuse atrophy, debris impaction, impaired rebound memory, and mechanical binding. Because apical migration of abutment teeth affects occlusion and oral hygiene, the authors make several recommendations for treatment planning for patients who have natural dentition adjacent to proposed implant sites.