Accuracy of impression methods through the comparison of 3D deviation between implant fixtures.

AIM: To compare the accuracy of three impression methods by comparing the distance between the reference points of the implant fixture, especially in curved maxillary anterior teeth. MATERIALS AND METHODS: Implant fixtures were placed in the maxillary central incisor and canine regions. A maxillary master cast was made using a model scanner and 3D printer. Ten impressions were taken from the three experimental groups constructed (group P: pick-up impression coping; group I: scan body with an intraoral scanner; group B: bite impression coping). The distance between the reference points, the angle between the scan bodies, and displacement of the 3D surface area were measured. RESULTS: The distances between the reference points were significantly different between groups I and B in the maxillary incisors, and between group P and the other two groups in the maxillary canines. Group P had the least amount of displacement in both fixtures. Both fixtures showed the highest displacement in group B. Displacement of the 3D surface area in the maxillary incisors showed no significant difference between the groups. There was a significant difference in the maxillary canines between groups P and I. CONCLUSIONS: In the present study, all three implant impression methods showed changes in the position and angle of the fixture compared with the master cast. The highest accuracy was shown by the impression method using the pick-up impression coping, but the impression method using the intraoral scanner also showed clinically acceptable accuracy. It should be noted that errors may occur when taking impressions using a bite impression coping.

Influence of intraoperative sevoflurane or desflurane on postoperative sore throat: a prospective randomized study.

PURPOSE: Tracheal intubation for general anesthesia causes postoperative sore throat. The purpose of this study was to evaluate the effect of sevoflurane and desflurane on prevalence of postoperative sore throat in patients after general anesthesia. METHODS: Ninety-six patients scheduled for orthopedic lower extremity surgery under general anesthesia were assigned to sevoflurane group or desflurane group. In the sevoflurane group (n = 48), sevoflurane was used as a maintenance anesthetic agent. In the desflurane group (n = 48), desflurane was used. Prevalence of sore throat, number of patients with rescue analgesics, and analgesics requirements were evaluated. RESULTS: The overall prevalence of postoperative sore throat in the sevoflurane group was lower than that in the desflurane group [21 (44%) vs. 32 (67%), p = 0.024]. The prevalence of sore throat at postoperative 4 h in the sevoflurane group was lower than that in the desflurane group [6 (13%) vs. 18 (38%), p = 0.005]. The number of patients requiring rescue analgesics was lower in the sevoflurane group [25 (52%) vs. 36 (75%), p = 0.020]. The requirement of diclofenac was also lower in the sevoflurane group (30 ± 37 mg vs. 47 ± 40 mg, p = 0.031). CONCLUSIONS: We have shown that sevoflurane was associated with less frequent sore throat than desflurane in patients undergoing orthopedic lower extremity surgery.