Impression & Prosthesis Quality Made From Different Polyvinylsiloxane Impression Techniques

Clinical Evaluation of Impressions Made Using One Step & Two Step Polyvinylsiloxane Impression Techniques and Resulting Fixed Prosthesis-A Randomised Controlled Trial

This randomized controlled trial is to clinically assess and compare impression quality of polyvinylsiloxane impression material using one step (experimental) and two step (control) impression techniques and its effect on marginal fit of prosthesis and proximal contact of prosthesis.

Study participants will be randomly allocated to either of the two groups (experimental or control) through software-generated random numbers. Indicated tooth will be prepared to receive a fixed prosthesis under local anesthesia as per standard guidelines. Polyvinylsiloxane (PVS) impressions will be recorded in stock tray after moisture control, according to the assigned group. In experimental group, light body and putty PVS will be mixed simultaneously and placed in stock tray to record impressions in single stage. In control group, a putty PVS impression will be recorded first in stock tray and allowed to set. After setting of putty PVS, light-bodied PVS material will be applied to recorded impression surface and reseated in mouth to record final impression in second stage. All impressions will be disinfected according to the recommended guidelines. All impressions will then be assessed by a senior clinician using 3.5 x magnification loupe and graded according to the selected criteria. Impressions will then be poured in dental stone and prosthesis will be manufactured in dental lab. Participants will be recalled for prosthesis trial and fit assessment of prosthesis margins using a dental explorer instrument and visual evaluation. Proximal contact of prosthesis will be graded according the criteria and assessed using dental floss. Satisfactory prostheses will be cemented after final adjustments.

Endodontically Treated Teeth, Missing Teeth, Discoloration, Tooth, Prosthesis Failure, Dental, Open Margin on Tooth Restoration

Polyvinylsiloxane impression, fixed prosthetics, impression techniques, single stage impression, two step putty wash impression, marginal fit, prosthesis fit, endodontically treated teeth

All impressions in this group will be recorded in a single stage, mixing light-bodied PVS material and putty PVS material simultaneously and recording of impression of prepared tooth

All impressions in this group will be made in two stages, recording putty PVS impression first and then reloading it with light-bodied PVS material to record final impression.

Incidence of defects in impression recorded to fabricate dental prosthesis as assessed by impression quality assessment scale

Outcome assessment scale: 1. Perfect impression, no voids or defects; 2. Acceptable impression, minimal defects in non critical region; 3. Unacceptable impression, defects involving critical region.

Outcome assessment scale: 1. Adequate, adapted to tooth margins; 2. Inadequate, not accurately adapted to tooth margin

Incidence of prosthesis proximal contact inaccuracy as assessed by prosthesis contact assessment scale

Outcome assessment scale: 1. Acceptable, same as natural proximal contact on contralateral side; 2. Unacceptable; either tight or open proximal contact.

Inclusion Criteria: Indication of fixed-fixed partial denture or crown Good oral hygiene Sound abutment tooth (vital/non-vital) Exclusion Criteria: Failure to provide written consent to participation in study Long span bridges (Greater than 3 units) Patients with bleeding disorders Cases indicated for resin-bonded prosthesis