Health-related quality of life, jaw function and sleep-disordered breathing among patients with dentofacial deformity.

BACKGROUND AND OBJECTIVES: Patients with dentofacial deformity (DFD) requiring orthognathic treatment have poor aesthetics, jaw function and psychological well-being, which potentially affect the quality of life. This study aimed to investigate the health-related general, oral and orthognathic quality of life, jaw function and sleep-disordered breathing at different stages of orthognathic surgical treatment. METHODS: A total of 120 consecutive patients with DFD were recruited and grouped as pre-orthodontic treatment (group 1), pre-surgery (group 2), 4 months post-surgery (group 3), 24 months post-surgery (group 4) and in addition 30 controls without DFD (group 0). Outcomes were assessed using general health Short Form Survey (SF-36), Oral Health Impact (OHIP-14), Orthognathic Quality of Life Questionnaire (OQLQ), STOP-Bang and Jaw Function Limitation Scale (JFLS) questionnaires. In addition, presence or absence of pain was recorded. Data were tested with analysis of variance, Kruskal-Wallis test, Tukey post hoc test and structural equation modelling (SEM). RESULTS: Results revealed SF-36 (p = .814) and STOP-Bang (p = .143) total scores did not differ between control and treatment groups. In contrast, OHIP-14, OQLQ and JFLS total scores differed between groups (p = .001). Higher scores were observed in groups 1 (p = .001), 2 (p = .001) and 3 (p = .041) compared to group 0, indicating poor oral health in patients with DFD. Importantly, in group 4, oral health-related quality of life was better, and OHIP-14 (p = .936) and JFLS (p = .572) scores did not differ from controls. OQLQ scores of group 4 were significantly lower than group 1 (p = .001) but higher than group 0 (p = .013). SEM results revealed a significant negative associations of pain with JFLS and OQLQ; OHIP-14 with OQLQ; OHIP-14 with SF-36; and finally STOP-Bang with SF-36. Positive associations were observed between JFLS and OHIP-14; OHIP-14 and OQLQ. CONCLUSION: Oral health-related quality of life and jaw function appears to be improved 24 months after orthognathic surgery. Pain and limitation in jaw function had a negative association with health-related quality of life.

Associations between temporomandibular disorders, pain, jaw and masticatory function in dentofacial deformity patients: A cross-sectional study.

BACKGROUND AND OBJECTIVE: Patients with dentofacial deformity often present with impaired masticatory function, orofacial pain and temporomandibular disorders (TMD). This study investigates the relationship between TMD, pain, jaw and masticatory function at different stages of orthognathic surgical (OS) treatment. METHODS: A total of 120 OS patients were prospectively recruited and grouped as pre-orthodontic (group 1), pre-surgery (group 2), 4-month post-surgery (group 3), 24-month post-surgery (group 4), in addition to 30 controls (group 0). Outcomes were assessed using: Jaw Function Limitation Scale (JFLS), McGill pain questionnaire, DC/TMD instrument, voluntary maximum bite force (MVBF), and masticatory efficiency (ME) using two-coloured chewing gum. Data were analysed using structural equation modelling. RESULTS: The prevalence of non-painful TMD did not differ between groups (p = .827). However, the prevalence of painful TMD differed between groups (p = .001). Among the painful TMDs, the highest prevalence was observed for masseter myalgia in group 2 (p = .031), and importantly group 4 did not differ from group 0 (p = .948). The MPQ score was significantly higher in group 1 (p = .001) compared to group 0, and the JFLS score was significantly higher in groups 1, 2 and 3 compared to group 0. Notably, MPQ (p = .756) and JFLS (p = .572) scores in group 4 were not different from group 0. However, MVBF (p = .996) and ME (p = .991) did not differ between groups 1 and 4. The association of self-reported pain and jaw function with the masticatory function was observed in OS patients. CONCLUSION: OS was not associated with a negative impact on TMD. Jaw function and pain levels were similar to controls at the 24-month follow-up. The masticatory function was further affected by the surgery and seems to require a longer recovery time. Moreover, it was confirmed that pain and TMD were associated with limitations in jaw function and impacts on masticatory function.

Pharyngeal airway changes five years after bimaxillary surgery - A retrospective study.

The aim of this study was to retrospectively evaluate pharyngeal airway (PA) changes after bimaxillary surgery (BMS). Preoperative, immediate- and 5-year postoperative cone-beam computed tomography images of subjects who underwent BMS were assessed. The primary outcome variable was the PA volume. The secondary outcome variables were the retropalatal and oropharyngeal volumes, cross-sectional area, minimal hydraulic diameter, soft tissue, skeletal movements and sleep-disordered breathing (SDB). A total of 50 patients were included, 33 female and 17 male, with a mean age of 26.5 years. A significant increase in the PA volume was seen immediately after surgery (40%), and this increase was still present at 5-year follow-up (34%) (P < 0.001). A linear mixed model regression analysis revealed that a mandibular advancement of ≥5 mm (P = 0.025) and every 1-mm upward movement of epiglottis (P = 0.016) was associated with a volume increase of the oropharyngeal compartment. Moreover, ≥5-mm upward movement of hyoid bone (P = 0.034) and every 1-mm increase in minimal hydraulic diameter (P < 0.001) correlated with an increase of the PA volume. A total of 30 subjects reported improvement in the SDB at 5-year follow-up. This study demonstrated that BMS led to an increase in PA dimensions in non-OSA patients, and these changes were still present at 5-year follow-up. BMS seemed to induce clinical improvement in SDB.

Reliability of radiographic findings in large FOV CBCTs of mandibular third molars as basis for pre-operative patient information.

OBJECTIVE: The aim of this study was to assess the relation between radiographic findings in large field of view (FOV) cone beam computed tomography (CBCT) exams and clinical findings of mandibular third molars in relation to the pre-operative patient information. MATERIAL AND METHODS: Two hundred and nine mandibular third molars in 134 orthognathic patients examined with CBCT were removed. Three observers assessed tooth- and mandibular canal-related variables in CBCT images, and the findings were correlated to clinical findings during surgery for all observers: tooth angulation, number and morphology of roots and close relationship between the tooth and the mandibular canal. Moreover, positive (PPV) and negative (NPV) predictive values and positive (LR+) and negative (LR-) likelihood ratios were calculated for the canal-related variables. Inter- and intra-observer reproducibility was expressed as percentage accordance and kappa-statistics. RESULTS: Generally, there was high correlation between radiographic and clinical tooth-related variables. The opposite was true for the canal-related variables, since the PPV and LR + were low. The highest PPV and LR + were found when the mandibular canal was positioned between the roots of the third molar. CONCLUSIONS: Tooth-related findings in CBCT are reliable, whereas mandibular canal-related findings should not affect the information provided to the patient pre-operatively.

Virtual Analysis of Segmental Bimaxillary Surgery: A Validation Study.

PURPOSE: Three-dimensional (3D) assessment of orthognathic surgery is often time consuming, relies on manual re-identification of anatomical landmarks or is limited to non-segmental osteotomies. The purpose of the present study was to propose and validate an automated approach for 3D assessment of the accuracy and postoperative outcome of segmental bimaxillary surgery. METHODS: A semi-automatic approach was developed and validated for virtual surgical analysis (VSA) of segmental bimaxillary surgery using a pair of pre- and postoperative (2 weeks) cone-beam computerized tomography (CBCT) scans. The output of the VSA, the accuracy of the surgical outcome, was calculated as 3D translational and rotational differences between the planned and postoperative movements of the individual bone segments. To evaluate the reliability of the proposed VSA, intra-class correlation coefficients (ICC) were calculated at a 95% confidence interval on measurements of 2 observers. The VSA was deemed reliable if the ICC was excellent (> 0.80) and the absolute difference of the repeated intra- and inter-observer translational and rotational measurements were significantly lower (p < 0.05) than a hypothesized clinical relevant threshold of 1 voxel (0.45 mm) and 1 degree, respectively. RESULTS: A total of 10 subjects (6 male; 4 women; mean age 24.4 years) with skeletal class 2 and 3, who underwent segmental bimaxillary surgery, 3-piece Le Fort I, bilateral sagittal split osteotomy and genioplasty, were recruited. The intra- and inter-observer reliability was excellent, ICC range [0.96 - 1.00]. The range of the mean absolute difference of the repeated intra- and inter-observer translational and rotational measurements were [0.07 mm (0.05) - 0.20 mm (0.19)] and [0.11˚ (0.08) - 0.63˚ (0.42)], respectively. This was significantly lower than the hypothesized clinical relevant thresholds (P < .001). CONCLUSION: The validation showed that the VSA has excellent reliability for quantitative assessment of the postoperative outcome and accuracy of segmental bimaxillary surgery.

Orthognathic Surgery-Induced Fibrinolytic Shutdown Is Amplified by Tranexamic Acid.

PURPOSE: Little is known of the systemic effects of oral and maxillofacial surgery on the hemostatic balance, including the biochemical effects of tranexamic acid (TXA), on fibrin clot lysis. The present study investigated the effects of orthognathic surgery on fibrin lysis, fibrin structure, and D-dimer and evaluated the effect of TXA on these fibrinolytic measures. MATERIALS AND METHODS: The present double-blind, controlled, and randomized, placebo study included patients referred to the Department of Oral and Maxillofacial Surgery at the University Hospital of Southern Denmark-Esbjerg from August 2014 through September 2016. The patients were elective and had a diagnosis of maxillary or mandibular deficiency, either excessive or asymmetric. All patients underwent bimaxillary orthognathic surgery (OS) with or without maxillary segmentation or additional genioplasty. The patients were blindly randomized to treatment with TXA or placebo. The primary predictor variable was OS. The secondary predictor variable was an intravenous dose of 1 g of TXA or equivalent placebo preoperatively. Blood samples were collected before surgery and 5 hours after the initiation of surgery. The primary outcome variable was lysis of fibrin. The fibrin structure properties and D-dimer were secondary outcome measures. The Mann-Whitney U test was used for the within-group comparisons. The Wilcoxon signed rank test was used for the between-group comparisons. RESULTS: The sample included 96 patients; 45 received placebo and 51 received TXA. Fibrin lysis decreased after OS (P < .001). The fibrinolytic shutdown decreased significantly more in the TXA group than in the placebo group (P < .001). OS altered the fibrin structure properties with comparable effects in the 2 groups. D-dimer increased postoperatively but significantly less so in the TXA group than in the control group (P < .001). CONCLUSIONS: OS is associated with fibrinolytic shutdown and alters fibrin structure properties, driving the hemostatic balance in a prothrombotic direction. The fibrinolytic shutdown is significantly amplified by TXA.

Two-Year Postoperative Upper Airway Cone-Beam Computed Tomographic Outcomes Based on a Verified Upper Airway Analysis Following Bimaxillary Orthognathic Surgery.

PURPOSE: Upper airway (UA) assessment after orthognathic surgery should rely on a verified method of UA analysis. Therefore, the authors applied a new validated UA evaluation method to determine the effect of bimaxillary surgery (BMS) on UA parameters and hyoid bone and epiglottis displacement evaluated immediately and 2 years after surgery. MATERIALS AND METHODS: A retrospective cohort study was implemented of patients without obstructive sleep apnea who had undergone BMS for maxillomandibular deficiencies. A new validated UA cone-beam computed tomographic (CBCT) analysis, based on stable anatomic landmarks, was applied to CBCT scans acquired before initiation of treatment (T0), immediately after surgery (T1), and 2 years postoperatively (T2). A quality assessment was performed before analysis. The primary predictor variable consisted of time points during treatment (T0, T1 and T2), and UA volumes, cross-sectional area (CSA), and hyoid bone and epiglottis displacement were the outcome variables. Descriptive statistics and t test were performed and the P value was set at .05. RESULTS: Fifty patients (16 men and 34 women) with a mean age of 25.7 ± 8.2 years at time of surgery were included. CBCT scans were acquired at T0 (20 ± 9 months before surgery), T1 (14 ± 2 days after surgery), and T2 (30 ± 6 months after surgery). Immediately after surgery (T1 vs T0), BMS resulted in a statistically relevant UA volume increase of 26%. At 2-year follow-up (T2 vs T0), UA volume showed a statistically relevant increase by 20%. CSA increased by approximately 26 and 19% (P < .001) at T1 versus T0 and T2 versus T0, respectively. Two years after surgery, epiglottis displacement was 2 mm (P < .001) and hyoid bone displacement was 3 mm (P < .001) in a cranial direction and hyoid bone anterior displacement measured 3 mm (P < .001). CONCLUSIONS: Based on an objective, standardized, and validated CBCT UA analysis, BMS was associated with increased UA volume and CSA measures evaluated immediately and 2 years after surgery.

The Effect of Tranexamic Acid and Gender on Intraoperative Bleeding in Orthognathic Surgery-A Randomized Controlled Trial.

PURPOSE: The purpose of this randomized trial was to measure the effect of intravenously administered tranexamic acid (TXA) on intraoperative blood loss (IOB) in patients undergoing bimaxillary orthognathic surgery (OS). MATERIALS AND METHODS: The authors designed and implemented a double-blinded placebo-controlled trial composed of patients eligible for OS at the Hospital of South West Denmark (Esbjerg, Denmark) from August 2014 through September 2016. The primary predictor variable was a single intravenous dose of TXA 1 g administered preoperatively or an equivalent saline placebo. The primary outcome was IOB determined by milliliters of blood in the suction canister and gauzes deducted from the volume of saline used intraoperatively. RESULTS: The study population consisted of 96 patients. The TXA group (n = 51) and the placebo group (n = 45) showed a median IOB of 275 and 403 mL (P = .005), respectively. A significant effect of TXA was detected in women (median IOB, 153 mL [96 to 233 mL] in TXA group vs 329 mL [185 to 582 mL] in placebo group; P < .001), whereas no significant effect of TXA on IOB was detected in men (median IOB, 367 mL [275 to 472 mL] in TXA group vs 429 mL [275 to 655 mL] in placebo group; P = .23). No correlations were found between IOB and procedure length, procedure type, or hematologic markers (platelets, hemoglobin, and hematocrit). CONCLUSION: In contrast to other studies, this double-blinded randomized controlled trial found a hemostatic effect of TXA in women and none in men who underwent bimaxillary OS. To focus on the specific effect of TXA in men, future studies should include larger male samples.

Can Preoperative Sex-Related Differences in Hemostatic Parameters Predict Bleeding in Orthognathic Surgery?

PURPOSE: Bleeding volume in orthognathic surgery (OS) varies considerably, although OS comprises standardized procedures and the patient population consists of young healthy individuals. The aim of this prospective cohort study was to investigate the influence of preoperative sex-related differences in hemostatic parameters on intraoperative bleeding (IOB) volume in OS. MATERIALS AND METHODS: Patients scheduled for routine OS in our department in Esbjerg, Denmark, were included as study patients in this short-term cohort study. The primary predictor variable was patient sex, and the primary outcome variable was IOB volume measured in milliliters. Secondary outcome variables included preoperative measures of hematologic variables, thromboelastography, fibrinogen concentration, D-dimer concentration, prothrombin fragment 1+2 (F1+2) concentration, and type of osteotomy. Data analyses included the χ(2) test, Mann-Whitney U test, Pearson product moment correlation analysis, and analysis of covariance for analyses of dichotomous variables, comparison between sex, correlations between IOB volume and secondary predictors, and adjustment for confounders, respectively. RESULTS: Forty-one consecutive patients undergoing bimaxillary OS were included and subsequently grouped according to sex (26 men and 15 women). The main finding was that male patients bled twice as much as female patients on average (400 mL [interquartile range, 300 to 500 mL] vs 200 mL [interquartile range, 63 to 288 mL]; P = .001). Age and preoperative measures of thromboelastography, fibrinogen concentration, D-dimer concentration, and F1+2 concentration were significantly associated with sex (P = .001, P = .002, P = .007, and P = .014, respectively). The significant association between sex and IOB volume disappeared when adjusted for these confounders (P = .18). CONCLUSIONS: Preoperative sex-related increases in measures of fibrin turnover predict IOB volume in bimaxillary OS, with women displaying a significantly lower IOB volume than men.

Prevention of Bleeding in Orthognathic Surgery--A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

PURPOSE: The objective of the present study was to evaluate the efficacy of hemostatic adjuncts on intraoperative blood loss (IOB) in orthognathic surgery (OS) detected by randomized controlled trials (RCTs) of the highest quality. MATERIALS AND METHODS: A search of the Medline, Cochrane, Embase, and Web of Science databases was performed in January 2015, and the risk of bias was assessed using the Jadad and Delphi scales. The predictor variable was the hemostatic measures, and the main outcome variable was the total IOB volume. The secondary outcome variables were the hemoglobin and hematocrit and operating time. This review is registered at PROSPERO (CRD42014014840). RESULTS: Eleven trials were included for review. The individual trials demonstrated the effects on IOB from hypotensive anesthetic regimens, the use of aprotinin, and the herbal medicine Yunnan Baiyao. Six studies of tranexamic acid (TXA), with 288 patients, were suitable for a meta-analysis of continuous data. TXA reduced IOB by an average of 171 mL (95% confidence interval [CI] -230 to -112; P < .00001). Its topical use yielded similarly significant results (mean difference -197, 95% CI -319 to -76; P < .001). A subgroup analysis showed a decreased operating time in the TXA groups by an average of 15 minutes (mean difference -14.78, 95% CI -22.21 to -7.35; P < .0001). CONCLUSIONS: Efficient hemostatic adjuncts exist for OS. Our meta-analysis showed that TXA significantly reduces IOB by an average of one third, regardless of whether it was given intravenously (IV) or applied topically. Additional RCTs are needed to confirm the effect of topical TXA in OS, and larger studies of intravenous administration are needed before any routine recommendations. No hemostatic effect of hypotensive anesthesia was found, mainly owing to imprecise descriptions of the blinding procedures. Transparent and uniform trial reporting is thus encouraged in future studies.

Improved apnea-hypopnea index and lowest oxygen saturation after maxillomandibular advancement with or without counterclockwise rotation in patients with obstructive sleep apnea: a meta-analysis.

PURPOSE: This study investigated whether patients with obstructive sleep apnea (OSA) who undergo maxillomandibular advancement (MMA) with counterclockwise (CCW) rotation compared with those who undergo MMA without CCW rotation have better outcomes. MATERIALS AND METHODS: This was a systematic review with meta-analysis. The Medline and Cochrane databases were searched for randomized controlled trials using Medical Subject Headings. The predictor variable was operative technique, namely MMA with or without CCW rotation of the maxillofacial complex. The key outcome variables were changes in pre- and postsurgical values of pharyngeal volume measured on computed tomogram or cone-beam computed tomogram and changes in Apnea-Hypopnea Index (AHI) and lowest oxygen saturation (LSAT) values after surgery. Data were subjected to a meta-analysis based on odds ratios (OR) with 95% confidence intervals (CIs) and P values lower than .05 by χ(2) test were considered significant. RESULTS: Twenty-one randomized controlled trials were identified and 4 were assessed for the variables of interest. Postoperative AHI and LSAT measurements showed vast improvement. The sample was not large enough to make a correlation between pharyngeal volume changes and surgical method used. Postoperative parameters included an AHI lower than 5 (OR = 14.9; 95% CI, 2.7-83.5; P = .002), an AHI lower than 20 (OR = 114.8; 95% CI, 23.5-561.1; P <.00001), pooled results of a 50% decrease in the AHI (OR = 6.1; 95% CI, 2.2-17.0; P = .0006), and an increase greater than 90% in LSAT measurements during sleep (OR = 6.0; 95% CI, 1.8-19.9; P = .003). The funnel plot showed no evidence of publication bias. CONCLUSION: CCW-MMA or MMA in patients with OSA results in a statistically meaningful decrease in postoperative AHI and a statistically meaningful increase in postoperative LSAT.

Intraoperative blood loss during orthognathic surgery is predicted by thromboelastography.

PURPOSE: The aim of this prospective study was to evaluate the predictive value of the viscoelastic properties of whole blood samples collected preoperatively in relation to intraoperative blood loss in patients subjected to orthognathic surgery. MATERIALS AND METHODS: Forty-one consecutive patients underwent simultaneous mandibular and maxillary osteotomy. Whole blood samples were collected preoperatively. The intraoperative blood loss volume was precisely estimated. The viscoelastic properties of whole blood samples were evaluated by thromboelastography (TEG), a global method that addresses the complex interplay among coagulation factors, blood platelets, and components of the fibrinolytic system. Blood platelet count, activated partial thromboplastin time, prothrombin time, plasma fibrinogen concentration, and D-dimer concentration were determined by routine methods. RESULTS: Patients were separated into 2 groups according to their intraoperative bleeding volume (≤ 400 mL and >400 mL). No significant associations were observed between routine coagulation tests and intraoperative bleeding volume. The TEG results for the groups were compared. Significant associations were observed between intraoperative blood loss and the clot formation time, maximum clot firmness, and α angle, whereas bleeding volume was not related to the fibrinolytic resistance of the blood clot. An α angle exceeding 67° predicted with 95% certainty a blood loss of 400 mL or less. CONCLUSIONS: We conclude that intraoperative bleeding volume in patients subjected to orthognathic surgery can be predicted by means of preoperative TEG analysis. TEG results provide optimization of patient safety and can be used for the evaluation of bleeding risk.