Background:
The accuracy of final impressions and master casts is critical for the fit and function of complete dentures. Discrepancies between clinical situations, impressions, and master casts can compromise prosthetic outcomes.

Aim:
This prospective analytical survey aimed to evaluate criteria of secondary impressions and master casts, analyse their validity and application in the subsequent prosthetic workflow, and compare the consistency of impression and cast validation criteria between the clinician investigator and the dental laboratory technician.

Material and methods:
A total of 101 secondary maxillary impressions and 84 master casts were analysed over a four-month period. Impressions and casts were independently assessed by the clinician investigator and technician.

Results:
Defects were observed in 99% of impressions by the clinician investigator and 83.2% by the technician. Most common defects included compression, air bubbles and voids. Agreement between clinician investigator and technician evaluations was 67% for impressions and 78.6% for master casts. Significant associations were found between the materials used and defects such as tissue compression (p = 0.017) and poorly defined anatomical landmarks (p = 0.042).

Conclusions:
Despite shared evaluation criteria, clinicians and technicians differed in their validation decisions, highlighting the importance of interprofessional communication.