Methods: The Procera scanner datasets derived from the resin patterns of all titanium custom abutments produced in the Conservation Laboratory at the Eastman Dental Institute between January 2001 and May 2003 were obtained. This compromised a total of 64 abutments. Using computer software, the axial wall heights and convergence angles were recorded at eighteen sites around each abutment. The abutments were also divided into 4 segments to assess geometry in these areas (buccal-palatal, mesiobuccal-distopalatal, mesial-distal, and mesiopalatal-distopalatal).
Results: Of all sites measured, 11% possessed adequate axial wall height, 26.5% acceptable convergence, and 3% both acceptable axial wall height and convergence. 4.8% and 1.6% of abutments has all eighteen sites with acceptable height and convergence respectively. No abutment had all eighteen sites which exhibited both acceptable height and convergence.
Conclusions: According to the literature-derived standards, the majority of abutments possessed inadequate retention and resistance form. There exists scope to train dental technicians so that custom abutments with improved retention and resistance form can be produced.