An interim oral appliance as a screening tool during drug-induced sleep endoscopy to predict treatment success with a mandibular advancement device for obstructive sleep apnea.

PURPOSE: Previous studies have shown a wide range of efficacy (29 to 71%) of a mandibular advancement device (MAD) in the treatment of obstructive sleep apnea (OSA). Currently, the ability to preselect suitable patients for MAD therapy based on individual characteristics related to upper airway collapsibility is limited. We investigated if the use of non-custom interim MAD during drug-induced sleep endoscopy (DISE) could be a valuable screening tool to predict MAD treatment outcome. METHODS: In a single-center prospective study including a consecutive series of patients with OSA, we compared DISE outcomes with a MAD in situ with polysomnography results after 3 months of using the same MAD that was used during DISE. RESULTS: Of 41 patients who completed the study, the median apnea-hypopnea index (AHI) was 16.0 events/h [IQR 7.4-23.4]. Respiratory outcomes on polysomnography, including apnea index (AI), total AHI, AHI in supine position, and oxygen desaturation index, all significantly improved after 3 months of MAD treatment. With complete improvement of the upper airway obstruction with the MAD in situ during DISE in supine position, patients were 6.3 times more likely to be a responder to MAD treatment compared to patients with a persisting complete obstruction, although not statistically significant (OR 6.3; 95%CI 0.9-42.7; p = 0.060). CONCLUSION: The potential predictive value with regard to MAD therapy outcomes of the use of an interim MAD during DISE would be an important finding, since the prediction of MAD therapy outcome is of great clinical and scientific interest. A study with a larger cohort should be performed to further investigate our findings.

Equal effect of a noncustom vs a custom mandibular advancement device in treatment of obstructive sleep apnea.

STUDY OBJECTIVES: Numerous types of mandibular advancement devices (MADs) are available to treat patients with obstructive sleep apnea, varying from noncustom to custom devices. Only a limited number of studies have been performed to determine whether a noncustom MAD could be used to predict treatment success of a custom MAD. In this study, we investigated the potential of a new-generation noncustom MAD, by comparing its effectiveness with a custom MAD. We hypothesized that the effectiveness of the devices is similar with regard to both objective (polysomnography) and self-reported (questionnaires, adherence, and patient satisfaction) outcomes. METHODS: This was a single-center prospective randomized crossover study including a consecutive series of patients with obstructive sleep apnea. Patients were randomized to start either with the noncustom or custom MAD. Both MADs were applied for 12 weeks, followed by polysomnography with MAD in situ and questionnaires. After the first 12 weeks of follow-up, a washout period of 1 week was applied. Equal effectiveness was defined as no significant differences in both objective and self-reported outcomes between both devices. RESULTS: Fifty-eight patients were included; 40 completed the full follow-up. The median apnea-hypopnea index significantly decreased from 16.3 (7.7, 24.8) events/h to 10.7 (5.6, 16.6) events/h with the custom MAD (P = .010) and to 7.8 (2.9, 16.1) events/h with the noncustom MAD (P < .001). Self-reported outcomes significantly improved in both groups. No significant differences were found between both devices. CONCLUSIONS: The effectiveness of a noncustom and custom MAD is comparable, which suggests that a noncustom MAD can be used as a selection tool for MAD treatment eligibility to improve MAD treatment outcome. CLINICAL TRIAL REGISTRATION: Registry: Netherlands Trial Register; Name: The Use of a Boil and Bite Mandibular Advancement Device vs a Custom Mandibular Advancement Device in Obstructive Sleep Apnea Management; URL: https://www.trialregister.nl/trial/7249; Identifier: NL64738.100.18. CITATION: Bosschieter PFN, Uniken Venema JAM, Vonk PE, et al. Equal effect of a noncustom vs a custom mandibular advancement device in treatment of obstructive sleep apnea. J Clin Sleep Med. 2022;18(9):2155-2165.

Digital three-dimensional image fusion processes for planning and evaluating orthodontics and orthognathic surgery. A systematic review.

The three important tissue groups in orthognathic surgery (facial soft tissues, facial skeleton and dentition) can be referred to as a triad. This triad plays a decisive role in planning orthognathic surgery. Technological developments have led to the development of different three-dimensional (3D) technologies such as multiplanar CT and MRI scanning, 3D photography modalities and surface scanning. An objective method to predict surgical and orthodontic outcome should be established based on the integration of structural (soft tissue envelope, facial skeleton and dentition) and photographic 3D images. None of the craniofacial imaging techniques can capture the complete triad with optimal quality. This can only be achieved by 'image fusion' of different imaging techniques to create a 3D virtual head that can display all triad elements. A systematic search of current literature on image fusion in the craniofacial area was performed. 15 articles were found describing 3D digital image fusion models of two or more different imaging techniques for orthodontics and orthognathic surgery. From these articles it is concluded, that image fusion and especially the 3D virtual head are accurate and realistic tools for documentation, analysis, treatment planning and long term follow up. This may provide an accurate and realistic prediction model.

Registration of 3-dimensional facial photographs for clinical use.

PURPOSE: To objectively evaluate treatment outcomes in oral and maxillofacial surgery, pre- and post-treatment 3-dimensional (3D) photographs of the patient's face can be registered. For clinical use, it is of great importance that this registration process is accurate (< 1 mm). The purpose of this study was to determine the accuracy of different registration procedures. MATERIALS AND METHODS: Fifteen volunteers (7 males, 8 females; mean age, 23.6 years; range, 21 to 26 years) were invited to participate in this study. Three-dimensional photographs were captured at 3 different times: baseline (T(0)), after 1 minute (T(1)), and 3 weeks later (T(2)). Furthermore, a 3D photograph of the volunteer laughing (T(L)) was acquired to investigate the effect of facial expression. Two different registration methods were used to register the photographs acquired at all different times: surface-based registration and reference-based registration. Within the surface-based registration, 2 different software packages (Maxilim [Medicim NV, Mechelen, Belgium] and 3dMD Patient [3dMD LLC, Atlanta, GA]) were used to register the 3D photographs acquired at the various times. The surface-based registration process was repeated with the preprocessed photographs. Reference-based registration (Maxilim) was performed twice by 2 observers investigating the inter- and intraobserver error. RESULTS: The mean registration errors are small for the 3D photographs at rest (0.39 mm for T(0)-T(1) and 0.52 mm for T(0)-T(2)). The mean registration error increased to 1.2 mm for the registration between the 3D photographs acquired at T(0) and T(L). The mean registration error for the reference-based method was 1.0 mm for T(0)-T(1), 1.1 mm for T(0)-T(2), and 1.5 mm for T(0) and T(L). The mean registration errors for the preprocessed photographs were even smaller (0.30 mm for T(0)-T(1), 0.42 mm for T(0)-T(2), and 1.2 mm for T(0) and T(L)). Furthermore, a strong correlation between the results of both software packages used for surface-based registration was found. The intra- and interobserver error for the reference-based registration method was found to be 1.2 and 1.0 mm, respectively. CONCLUSION: Surface-based registration is an accurate method to compare 3D photographs of the same individual at different times. When performing the registration procedure with the preprocessed photographs, the registration error decreases. No significant difference could be found between both software packages that were used to perform surface-based registration.

Three dimensional measurement of rhinoplasty results.

BACKGROUND: Pre- and postoperative imaging is important and essential for evaluation of the results of rhinoplasty surgery. Two-dimensional photographs are used routinely for this purpose, but have several disadvantages as opposed to three-dimensional imaging techniques, such as stereophotogrammetry. This study is the first to describe the measurement of rhinoplasty results using stereophotogrammetry. The aim of this study was to evaluate the ability of 3D imaging to measure and objectify rhinoplasty results. METHODS: During a 6-month period all consecutive hump reduction patients were included in this prospective study. Pre- and postoperative 3D photographs were taken and compared. RESULTS: Twelve patients were studied. In ten of these twelve patients a significant volume reduction in the area of the nasal dorsum was found with stereophotogrammetry. The maximum decrease (i.e. lowering) of the nasal dorsum ranged from 0.8 to 4.4 mm. In two patients no reduction of the nasal dorsum was found. In both patients this was due to additional changes made to the nose during surgery. These changes, increased tip rotation and dorsal augmentation respectively, were also documented with stereophotogrammetry. CONCLUSIONS: Both pronounced as well as subtle postoperative changes of rhinoplasty surgery can be objectified and measured with stereophotogrammetry. This tool can be used to study whether surgical techniques have the desired effect on the nose, and to compare different techniques with each other.

Unilateral craniosynostosis of the frontosphenoidal suture: a case report and a review of literature.

INTRODUCTION: Frontal plagiocephaly, a rare congenital deformation of the skull, is one of the most complicated forms of craniosynostosis to treat. The difference between deformational and synostotic frontal plagiocephaly is small. Moreover, the visible deformations are sometimes misleading and may lead to a treatment delay. A multislice CT scan with 3D reconstruction is the preferred diagnostic tool to differentiate between craniosynostosis and deformational causes of plagiocephaly. Still, meticulous examination of all sutures is necessary to exclude any form of craniosynostosis and to prevent misdiagnosis. AIM: A case is presented of a 1-month-old boy with a progressive deformation of the left forehead, which was caused by a stenosis of the left frontosphenoidal suture. METHODS: Surgical treatment consisted of a left fronto-orbital advancement. Furthermore, 3D stereophotogrammetry was used for long term follow up, which showed normalisation of the growth pattern of the skull. CONCLUSION: Isolated frontosphenoidal suture synostosis is a rare cause of frontal plagiocephaly with its own distinct clinical features. Accordingly, careful assessment of a 3D CT scan may reduce treatment delay. Furthermore, 3D stereophotogrammetry proved to be a radiation-free non-invasive patient-friendly method for long term follow up of a child with a skull deformation.

Integration of digital dental casts in 3-dimensional facial photographs.

INTRODUCTION: Since 1915, various researchers have tried to make a 3-dimensional (3D) model of the complete face, with the dentition in the anatomically correct position. This was a difficult and time-consuming process. With the introduction of 3D digital imaging of the face and dental casts, researchers have regained interest in this topic. The purpose of this technical report is to present a feasibility study of the integration of a digital dental cast into a 3D facial picture. METHODS: For the integration, 3 digital data sets were constructed: a digital dental cast, a digital 3D photograph of the patient with the teeth visible, and a digital 3D photograph of the patient with the teeth in occlusion. By using a special iterated closest point algorithm, these 3 data sets were matched to place them in the correct anatomical position. RESULTS: After matching the 3 data sets, we obtained a 3D digital model with the dental cast visible through the transparent picture of the patient's face. When the distance between the matched data sets was calculated, an average distance of 0.35 mm (SD, 0.32 mm) was shown. This means that matching the data sets is acceptable. CONCLUSIONS: It seems technically possible to make a data set of a patient's face with the dentition positioned into this 3D picture. Future research needs to establish the value of this 3D fused data set of the face and the dentition in orthodontic diagnosis and treatment planning.

3D stereophotogrammetry for the assessment of tracheostoma anatomy.

CONCLUSION: 3D stereophotogrammetry is a useful tool for quantitative assessment of tracheostoma anatomy, and thus in future could possibly play a role in solving current problems with peristomal and intratracheal fixation of stoma appliances. OBJECTIVES: Differences in tracheostoma anatomy between laryngectomized patients are held partly responsible for the differences in duration of attachment of standard peristomal adhesives for heat and moisture exchangers (HMEs) and automatic stoma valves (ASVs). Accurate information on a set of basic stoma anatomy parameters should be helpful to overcome fixation problems in individual patients and in the general laryngectomy population. PATIENTS AND METHODS: This was an exploratory observational pilot study in 20 laryngectomized patients. Three-dimensional (3D) images of the tracheostoma and surrounding tissue were captured with a 3D digital camera, which applies the advanced principles of stereophotogrammetry. Data were analysed by using a 3D editing program. The following tracheostoma parameters were measured for each patient: horizontal and vertical diameters, circumference, depth and surface. RESULTS: Inter-observer outcomes show a mean stoma circumference of 58.2 mm (SD 11.6 mm). The mean surface was calculated at 186.6 mm2 (SD 61 mm2). The mean size of the stoma's horizontal diameter and vertical diameter was 14.7 mm (SD 2.9 mm) and 19.0 mm (SD 3.4 mm), respectively. The mean depth of the stoma in relation to the right sternal head of the m. sternocleidomastoideus was 15.5 mm (SD 5.4 mm) and in relation to the left it was 16 mm (SD 5.6 mm).