Dimensional Stability of Casts Derived from Three Types of Alginate at Different Times After Impression

Objective: To evaluate the dimensional changes in three types of alginate following three different delay times after casting. Material and Methods: In this laboratory study, a maxillary arch-shaped stainless steel model was prepared and three pins with similar and determined diameters and heights were placed (one at mid-line and two on the underside of the model) as reference points to compare the dimensional stability of the three types of alginates. A special metal tray was made from the main model. The main moldel was imprisoned by the metal tray, and these were kept for a specific time in a humid environment. Gypsum Type 4 was poured over the impression to obtain 90 gypsum casts for three types of alginate. The dimensions of casts obtained from each alginate were compared in two lateral and anterior-posterior dimensions, they were compared with each other, and the alginates were also compared to the main model. Results: At a time interval of 15 minutes, the dimensional accuracy of the casts obtained from the three types of alginates, with the main model in both anterior-posterior and transverse dimensions was not significantly different (p<0.05); but there was a significant difference at 60 minutes and 24 hours in both dimensions (p<0.05). Although there was no significant difference between the alginates in both dimensions and all three studied time periods, the least difference with the main model was related to Zhermack and the highest difference was related to Golchai alginates. Pairwise comparisons showed that none of the samples had a significant difference in terms of dimensions. Conclusion: The dimensional stability of alginate was a time-dependent type of alginate and had no significant effect on the dimensional accuracy of casts.

Maxillary canine‒second molar transposition: A rare case report.

Tooth transposition, which is a rare condition, is ascribed to the disturbance of tooth eruption and the subsequent abnormal occlusal relationships. Transpositions mostly involve the upper jaw and more frequently occur between the maxillary canine and first premolar. Herein, we present a case of a maxillary canine‒second molar transposition in a thalassemic patient.

Comparison of Subacromial Ketorolac Injection versus Corticosteroid Injection in the Treatment of Shoulder Impingement Syndrome.

OBJECTIVE: Subacromial impingement syndrome is the most common cause of shoulder pain and restriction in range of motion in the world. The aim of this study was to compare the efficacy of subacromial injection of ketorolac with the injection of corticosteroid for the treatment of subacromial impingement syndrome. METHODS: A total of forty patients were randomly allocated into two groups. Group A received 40 mg of methylprednisolone and Group B received 60 mg of ketorolac as a subacromial injection along with lidocaine. Each patient was evaluated in terms of visual analog scale (VAS) for evaluating pain and Constant's score for function evaluation (pain, activity level, and range of motion with standard goniometry). The patients were re-examined 1 and 3 months after intervention. All the patients educated for simple home exercise. FINDINGS: At 1 and 3 months of follow-up, both treatment arms resulted in an increased range of motion and decreased pain. The difference between the groups was not statistically significant (P > 0.05). In ketorolac group, mean pre- and post-treatment (at 12 weeks) VAS scores were 8.6 (range, 3-9) and 4.5 (range 2-4), respectively. In steroid group, mean pre- and post-treatment (at 12 weeks) VAS scores were 8.3 (range, 3-10) and 3.9 (range, 0-7), respectively. The difference was statistically significant within groups at baseline and 1 (P < 0.001) and 3 (P < 0.001) months after the injection. CONCLUSION: Subacromial injection of ketorolac has an equivalent outcome to subacromial injection of corticosteroid. The use of ketorolac injections can substantially decrease the pain and increase the range of motion of the shoulder and could be a reasonable alternative in case of corticosteroid contraindications.