Is Virtual Surgical Planning in Orthognathic Surgery Faster Than Conventional Planning? A Time and Workflow Analysis of an Office-Based Workflow for Single- and Double-Jaw Surgery.

PURPOSE: The purpose of this study was to measure and compare the working time for virtual surgical planning (VSP) in orthognathic surgery in a largely office-based workflow in comparison with conventional surgical planning (CSP) regarding the type of surgery, staff involved, and working location. MATERIALS AND METHODS: This prospective cohort study included patients treated with orthognathic surgery from May to December 2016. For each patient, both CSP with manual splint fabrication and VSP with fabrication of computer-aided design-computer-aided manufacturing splints were performed. The predictor variables were planning method (CSP or VSP) and type of surgery (single or double jaw), and the outcome was time. Descriptive and analytic statistics, including analysis of variance for repeated measures, were computed. RESULTS: The sample was composed of 40 patients (25 female and 15 male patients; mean age, 24.6 years) treated with single-jaw surgery (n = 18) or double-jaw surgery (n = 22). The mean times for planning single-jaw surgery were 145.5 ± 11.5 minutes for CSP and 109.3 ± 10.8 minutes for VSP, and those for planning double-jaw surgery were 224.1 ± 11.2 minutes and 149.6 ± 15.3 minutes, respectively. Besides the expected result that the working time was shorter for single-versus double-jaw surgery (P < .001), it was shown that VSP shortened the working time significantly versus CSP (P < .001). The reduction of time through VSP was relatively stronger for double-jaw surgery (P < .001 for interaction). All differences between CSP and VSP regarding profession (except for the surgeon's time investment) and location were statistically significant (P < .01). The surgeon's time to plan single-jaw surgery was 37.0 minutes for CSP and 41.2 minutes for VSP; for double-jaw surgery, it was 53.8 minutes and 53.6 minutes, respectively. CONCLUSIONS: Office-based VSP for orthognathic surgery was significantly faster for single- and double-jaw surgery. The time investment of the surgeon was equal for both methods, and all other steps of the workflow differed significantly compared with CSP.

Life-threatening complications of deep neck space infections.

Odontogenic infections represented a challenge for every craniomaxillofacial surgeon in the pre-antibiotic era, not least due to the frequent association with septic complications and lethal consequences. Nowadays, the incidences of serious infection-related complications are less frequent thanks to the medical progress. Nevertheless, the development of severe infections is still hard to foresee. The following analysis provides an overview of four patients with severe, life-threatening odontogenic deep neck space infections treated at the University Clinic for Oral and Maxillofacial Surgery in Innsbruck and describes the etiology, therapy, and outcome for each patient while analyzing differences between the single cases. Crucial aspects in origin, progression, and treatment of DNIs are highlighted, comparing the results with the international literature.

Cephalometric variables discriminate among magnetic resonance imaging-based structural characteristic groups of the temporomandibular joint.

OBJECTIVE: The aim of this study was to assess retrospectively whether, in patients with temporomandibular joint (TMJ) arthralgia, commonly used cephalometric variables of dentofacial morphology can discriminate among magnetic resonanace imaging (MRI)-based TMJ structural characteristic groups of "uni- or bilateral disc displacement without reduction (DDwoR) associated with bilateral osteoarthrosis (OA)" and "uni- or bilateral disc displacement with reduction (DDwR) without OA." STUDY DESIGN: Bilateral MRI of the TMJ was performed in 56 consecutive TMJ arthralgia patients to identify individuals with specific structural characteristic of uni- or bilateral TMJ DDwoR, DDwR, and OA. Application of the criteria resulted in a study group of 31 patients with "uni- or bilateral DDwoR with bilateral OA" and 25 with "uni- or bilateral DDwR without OA." Linear and angular cephalometric measurements were taken from lateral cephalograms to apply selected criteria of dentofacial morphology. One-way analysis of variance was used to assess differences in cephalometric variables by MRI-based TMJ group. Then, discriminant function analysis predicted TMJ group membership. RESULTS: A-B plane to facial plane angle, palatal plane to occlual plane, and interincisal angle produced a significantly discriminant function that predicted TMJ group membership (P < .001). This function correctly classified 85.7% of original grouped cases. CONCLUSIONS: Cephalometric variables may discriminate among MRI-based TMJ structural characteristic groups. Additional diagnostic information related to MRI-based classification groups was generated.

Characteristics of pulpal blood flow levels associated with non-segmented and segmented Le Fort I osteotomy.

OBJECTIVES: Laser Doppler flowmetry (LDF) is a noninvasive method to assess pulpal blood-flow (PBF). The purpose of this study was (1) to test whether Le Fort I (LF-I) osteotomy may show tooth type-related effects on LDF measurements, and (2) to investigate whether LF-I and tooth type may predict adverse PBF outcomes. MATERIAL AND METHODS: PBF was recorded bilaterally in maxillary incisors, canines, and first premolars in a surgical group of patients who underwent a segmented (n = 14) or nonsegmented LF-I osteotomy (n = 12), and in a nonsurgical group of control subjects (n = 12) who did not undergo orthodontic treatment. PBF measurements were made before surgery (session I), and at intervals between 3 and 5 days (session II), and 55 and 59 days after surgery (session III). The nonsurgical control subjects were tested at similar intervals. An adverse outcome was defined as the presence of "PBF reduction of > 40%." Statistical analysis consisted of univariate analysis of variance for repeated measurements. A multiple logistic regression analysis was used to compute the odds ratio for LF-I and tooth type for adverse outcome versus nonadverse outcome. RESULTS: For the LF-I osteotomy study group there was a significant change in PBF values (P = .000). Analysis of session-related measurements revealed a significant difference between session I- and II-related measurements for the canine (P = .004) of the segmented LF-I osteotomy. Significant increase in risk of a session II-related adverse outcome occurred with a nonsegmented (16.6 odds ratio) (P = .009) and segmented LF-I osteotomy (59.2 odds ratio) (P = .000). The odds ratio that a patient with a segmented LF-I osteotomy might belong to the session III-related adverse outcome group was strong (20.6) and significant (P = .007). CONCLUSIONS: LF-I osteotomy type proved to be linked to changes in tooth type-related LDF measurements; it was an important prognostic determinant of adverse PBF outcomes.