Evaluation of faults encountered in re-cording final impression

الملخص EN

To evaluate the quality of the impressions recorded for fixed and removable partial dentures and for completely edentulous patients by describing the frequency of clinically detectable errors.

Mate-rials and Methods : A total of 250 impressions were evaluated immediately after they were recorded by two examiners.

Three different impression materials were employed.

Data relating to errors and faults including those related to tray construction, or related to impression materials used and those related to the operator were evaluated and analyzed.

Results: Of 100 irreversible hydrocolloid impres-sions for partially edentulous arches, 90% had one or more detectable errors; while for condensation type of silicon 50% had one or more detectable errors.

For complete denture impressions, silicon rub-ber base showed the least errors than zinc oxide eugenol paste impression and irreversible hydrocolloid that showed the highest errors.

For fixed partial denture, impressions were recorded by silicon rubber base; the occurrence of faults were as follow: Voids in finish line 20%, detachment 6.6%, tearing 6.6%, premature removal 10% and pressure area 3.3%.

Conclusion : Irreversible hydrocolloid impression material showed the higher detectable errors.