The main purpose of the present study was to evaluate and compare the effectiveness of three kinds of commercially available desensitizing agents: Gluma, Sheildforce plus, and Telio CS desensitizers in reducing the pre- and post-cementation sensitivity for full coverage restorations.

During the first visit, standard prosthodontic principles were followed to prepare the teeth for complete coverage restorations using high-speed handpiece and copious water-coolant spray. After the effect of local anesthesia was worn off, baseline sensitivity (first reading) was recorded on the VAS using Cold Test and Electric Pulp Test (EPT) . Final impression using addition silicon (Virtual from Ivoclar Vivadent, Amherst, NY) was made, and the provisional prosthesis was fabricated using Protemp TM II (3M ESPE, Germany), by the direct method using polyvinyl siloxane putty (ExpressTM STD, 3M ESPE) matrix. The first application of desensitizer was done then on the desensitizer group according to the manufacturer's recommendation. The fabricated provisional prosthesis was cemented with non-eugenol provisional cement Tempbond NE (Rely XTM TempNE, 3M ESPE, Germany) and the patient was recalled for the metal try-in. During the second visit, the provisional prosthesis was removed and the patient's response to Cold Test and EPT was again recorded on VAS (second reading) and the metal try-in was carried out. The second application of desensitizing agent was done, the provisional prosthesis was re-cemented, and the patient was recalled for final cementation. During the third visit, the provisional prosthesis was removed, the patient's response to Cold Test and EPT was again recorded (third reading), and the third application of desensitizing agent was done before cementing the final prosthesis with G-cem resin cement. The control group had similar clinical steps except for the application of desensitizer, Evaluation of sensitivity level Subjective evaluation of pain produced by cold and electrical stimulus was done, for checking pre-cementation sensitivity. Before starting the procedure, patients were explained about the Cold Test, EPT, and the VAS scores.

Inclusion Criteria:

• The inclusion criteria were: minimum of one posterior tooth missing and patient in need of fixed dental prosthesis (porcelain fused to metal); abutment teeth with a vital pulp, normal apical periodontal ligament space, no history of hypersensitivity; and previous restorations not involving more than 50% of the coronal tooth surface.

Exclusion Criteria:

• The exclusion criteria were: patients with chronic diseases, gross oral pathology, or those undergoing any kind of medications; subjects with teeth that had extensive restorations, mobility or periodontal diseases; pregnant or lactating women; and individuals participating in any other clinical study.

Currently, there is no plan to share IPD. However, the interested researchers can request it directly to us if the need arises.

The application of the stimuli and the desensitizers and collection of subjects' responses during the visits was carried out by two well-trained examiners. After providing informed consent, the first examiner allocated a number to each patient. The patients were blinded to whether they were in the control group or one of the desensitizer groups. The application of the agents was also carried out by the same examiner. The tests were carried out by the second examiner who also recorded the sensitivity during the visits. Group allotment and the application of the agents were thus carried out by the first examiner, which were concealed from the second examiner who assessed and recorded the sensitivity scores, making the study double-blinded.