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Updated: May 14, 2026

A Postoperative Evaluation Guideline for Computer-Assisted Reconstruction of the Mandible
Published on: January 28, 2020
A retrospective comparison of implants in the pterygomaxillary region: implant placement with two-stage,
Thomas J Balshi1, Glenn J Wolfinger, Robert W Slauch
1PI Dental Center at Institute for Facial Esthetics, Fort Washington, PA 19034, USA. balshi2@aol.com
Purpose:
Implants placed into the pterygomaxillary region allow for increased posterior support and a full complement of teeth without the need for distal cantilevers. With advancements in research and technology, implant delivery has evolved from the traditional two-stage procedure to immediate loading freehand and guided surgical template protocols. The purpose of this retrospective study is to determine if there is a significant difference in implant survival rates between these protocols.
Materials And Methods:
All pterygomaxillary implants placed in a single private practice from September 1985 to July 2011 were categorized into three separate classifications (two-stage freehand, single-stage freehand, or single-stage guided) by retrospective chart review. Life tables were constructed to determine the cumulative survival rates (CSR), and ANOVA was used to identify statistical significance.
Results:
A total of 981 patients comprising 371 males and 610 females were included in the study. Of all pterygomaxillary implants, 1,460 of 1,608 implants osseointegrated for a CSR of 90.80%. Seven hundred nine of the 825 two-stage, 624 of the 647 single-stage, and 127 of the 136 guided surgery implants osseointegrated for CSRs of 85.94%, 96.45%, and 93.38%, respectively. The comparison between two-stage and single-stage protocols was statistically significant, (P < .05) while the difference between single-stage guided versus freehand protocols was found to be statistically insignificant (P > .05).
Conclusion:
The results from this retrospective study reinforce that immediate loading of pterygomaxillary implants with a provisional prosthesis is beneficial to both doctor and patient. The lower CSR for the guided surgery protocol compared with the single-stage freehand procedure is statistically insignificant, suggesting guided surgery is still a viable and recommended option for qualified patients.
