All ETDs from UAB

Advisory Committee Chair

Perng-Ru Liu

Advisory Committee Members

Jack E Lemons

Daniel A Givan

Keith E Kinderknecht

Amjad Javed

Document Type


Date of Award


Degree Name by School

Master of Dentistry (MDent) School of Dentistry


Objectives: The specific aim of this study was to analyze any entrapped debris in implant abutment screw threads from post processed constructs from dental laboratories. Materials and Methods: Forty implant screws were used to collect debris where screws were removed from the implant prosthesis as received from dental laboratories. In all samples, laboratory procedures including fabrication of the custom abutment, definitive prosthesis and finishing/polishing were completed prior to sampling. Twenty-nine screws were from titanium and eleven screws were from zirconia abutments. Scanning Electron Microscope (SEM) analyses of collected particulate products from abutment screws were done for all specimens. Results: The SEM analysis showed multiple particles with different sizes, shapes and chemistries. Elemental analysis of these particles supported that their origin was from the abutment/prosthesis or transferred from other sources utilized in the dental laboratories during the fabrication processes. Conclusion: Based on the results it was concluded that particles on abutment screw surface were present and their characteristics may affect the abutment implant joint stability and/or may have a biological effect on peri-implant tissue health. Therefore a consistent method of cleaning is needed for abutment screws before clinical use of any screw and prosthesis received after processing by dental laboratories.

Included in

Dentistry Commons



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