Characteristics of CBCT versus panoramic signs of the surrounding bone of molar root protrusions into the maxillary sinus.

The study aimed to (a) investigate the amount and characteristics of the surrounding bone of protruded molar roots into the maxillary sinus using cone-beam computed tomography (CBCT) and (b) assess the correlation between the amount of bone with panoramic high-risk signs. Radiographs of 408 roots protruding beyond the sinus floor were evaluated. Axial CBCT images were used to investigate then classify eight characteristics of surrounding bone: no bone; bone < half the root girth in the proximal or buccal-palatal aspect; bone covering half the root girth in the proximal or buccal-palatal aspect; bone > half the root girth in the proximal or buccal-palatal aspect; and, complete bone. These were then grouped into four degrees of bone support: no bone; bone ≤ half the root girth; bone > half the root girth; and, complete bone. Panoramic signs were subclassified as: projection of root; interruption of the sinus floor; darkening of the root; upward curving of the sinus floor; absence of periodontal ligament space; and, absence of the lamina dura. Correlation between the degree of bone and the panoramic signs was evaluated using the Chi-square or Fisher's exact tests. Positive and negative predictive values, sensitivity, specificity, accuracy, and receiver operating characteristic analysis were calculated. Complete bone support was the most common. 'Projection of root' had a high negative predictive value and sensitivity. 'Absence of the periodontal ligament space and lamina dura' had a high positive predictive value, specificity, accuracy, and area under the curve. These two signs were significantly correlated with the degree of bone support.

Effect of single dose preoperative intramuscular dexamethasone injection on lower impacted third molar surgery.

This study aimed to investigate the effects of dexamethasone intramuscular injection 1h preoperatively, in reducing facial swelling, pain and trismus after lower impacted third molar (LITM) surgery. Twenty healthy Thai patients with both LITM surgical extraction were enrolled in the study. The washout period was 1 month after the first operation. Clinical assessment of the facial swelling, pain and trismus were measured before and after operation for 7 days and the patient's total analgesic consumption was recorded. The level of significance used in the statistical decisions was P<0.05. Preoperative intramuscular injection of single-dose 8mg dexamethasone reduced postoperative swelling after LITM surgical extraction significantly on the second postoperative day, but immediately after surgery and on day 7 after the surgical extraction, no significant difference was found between the dexamethasone and control groups. Dexamethasone also reduced postoperative pain after LITM surgical extraction significantly on postoperative days 2 and 7. Additionally, the amount of paracetamol decreased significantly. There were no significant differences in trismus in the study and control groups 7 days after LITM operation. Single-dose intramuscular injection of dexamethasone can reduce postoperative facial swelling and pain, without affecting trismus after LITM surgical extraction.

Does tranexamic acid in an irrigating fluid reduce intraoperative blood loss in orthognathic surgery? A double-blind, randomized clinical trial.

PURPOSE: The aim of this study was to investigate the efficacy of tranexamic acid in an irrigant fluid in decreasing intraoperative blood loss during orthognathic surgery. MATERIALS AND METHODS: This was a prospective, randomized, double-blind, placebo-controlled trial of elective bimaxillary osteotomy. Forty patients were included in the study and 20 were randomly assigned to each group. Drawing of random lots determined whether 0.05% tranexamic acid in normal saline solution or normal saline was used as an irrigant fluid during surgery. All patients underwent hypotensive anesthesia and surgery according to standard protocol. Intraoperative blood loss, operative and hypotensive times, preoperative and postoperative hematocrit levels, transfusion of blood product, and amount of irrigant fluid were recorded. Parametric data were reported as mean ± standard deviation and nonparametric data were counted. Changes in parametric variables were analyzed using unpaired Student t test. Two-sided significance tests were used. P < .05 was accepted as statistically significant. RESULTS: Blood loss during bimaxillary surgery was not decreased significantly in the tranexamic acid group compared with the control group (832.5 ± 315.5 vs 917.5 ± 424.0 mL, respectively, P = .47). CONCLUSIONS: Tranexamic acid in an irrigant fluid does not significantly decrease intraoperative blood loss compared with placebo during orthognathic surgery.