Dentofacial Deformities

The investigators are studying how speech is effected by jaw and tooth position in jaw surgery patients. Eighty percent of our jaw surgery patients have speech pathologies, compared to five percent of the general population, but speech pathologists do not understand why. The investigators hypothesize that open bites and underbites prevent most patients from being able to pronounce words normally and surgical correction will lead to improvement in speech. Patients will be audio recorded speaking and patients' tongue gestures ultrasound recorded before and after their jaw surgeries to observe what changes occur in their speech and tongue movements.

This study aims to develop and evaluate deep learning-based artificial intelligence models for craniomaxillofacial multi-modal imaging analysis and clinical decision support. Approximately 2,000 participants with craniomaxillofacial imaging data and related clinical information will be included. The imaging data may include two-dimensional facial photographs, cone-beam computed tomography images, and three-dimensional facial surface scans. The study will use artificial intelligence methods to analyze craniofacial images and identify clinically meaningful features related to facial morphology, skeletal or dental classification, anatomical landmarks, regional structures, and craniomaxillofacial abnormalities. The models will be developed for tasks such as image classification, anatomical landmark detection, image segmentation, abnormality recognition, and treatment-related decision support. The purpose of this study is to improve the accuracy, efficiency, and consistency of image-based assessment in dentistry, orthodontics, and oral and maxillofacial clinical practice. The artificial intelligence models developed in this study are intended to provide objective imaging analysis and decision-support information for health care providers. These models are designed to assist clinicians and will not replace professional diagnosis or individualized treatment planning by qualified clinicians. This research may benefit patients and families by supporting earlier and more accurate recognition of craniomaxillofacial conditions, improving communication about diagnosis and treatment options, and promoting more personalized oral health care. All clinical images and related information will be handled according to approved research procedures and privacy protection requirements.

Background: Some head and facial abnormalities are rare and present at birth. Others are more common, and may not show up until puberty. These conditions have different causes and characteristics. Researchers want to learn more about these conditions by comparing people with face, head, and neck abnormalities to family members and to healthy volunteers without such conditions. Objectives: To learn more about abnormal development of the face, head, and neck. To determine their genetic variants. Eligibility: People who have not had surgery for facial trauma: People ages 2 and older with craniofacial abnormalities (may participate offsite) Unaffected relatives ages 2 and older Healthy volunteers ages 6 and older Design: Participants will be screened with medical history and physical exam focusing on head, face, and neck Participants may be followed for several years. Visits may require staying near the clinic for a few days. A visit is required for the following developmental stages, along with follow-up visits: Age 2-6 Age 6-10 Age 11-17 Age 18 and older Visits may include: Medical history Physical exam Questionnaires Oral exam Blood and urine tests Cheek swab: a cotton swab will be wiped across the inside of the cheek several times. Cone beam CT scan (CBCT): x-rays create an image of the head, face, teeth, and neck. Participants will stand still or sit on a chair for about 20 minutes while the scanner rotates around the head. Photos of the head and face Offsite participants will provide: Copies of medical and dental records Leftover tissue samples from previous surgery Blood sample or cheek swab

This study aims to investigate the relationship between preoperative anxiety and intraoperative hemodynamic changes, as well as postoperative pain and facial edema, in patients undergoing orthognathic surgery. Orthognathic surgery is a corrective jaw surgery performed to treat dentofacial deformities. Although the procedure improves functional and aesthetic outcomes, patients may experience significant anxiety before surgery. Elevated anxiety levels may influence physiological responses during the operation and may affect postoperative recovery. In this study, preoperative anxiety levels will be evaluated using validated assessment scales prior to surgery. During the intraoperative period, hemodynamic parameters such as heart rate and blood pressure will be recorded. After surgery, postoperative pain and facial edema will be assessed using standardized clinical evaluation methods. The objective of this research is to determine whether higher levels of preoperative anxiety are associated with changes in intraoperative hemodynamic stability and increased postoperative discomfort. The findings may contribute to improved perioperative management strategies and enhanced patient care in orthognathic surgery.

This study aims to evaluate the clinical efficacy and positioning accuracy of a custom-made proximal segment positioning appliance designed for use in sagittal split ramus osteotomy (SSRO). The appliance is produced using STL-based digital planning and 3D printing technologies. In each patient, the appliance is applied to one side of the mandible while the contralateral side is positioned using the conventional manual method. This within-subject design enables direct comparison by eliminating inter-individual anatomical variability. The primary outcome is the accuracy of segment positioning, evaluated by 3D superimposition and deviation analysis of pre- and postoperative STL models. Secondary outcomes include surgical time, ease of use as rated by the surgeon, and postoperative temporomandibular joint symptoms. The study will enroll 30 adult patients undergoing SSRO or double-jaw surgery due to dentofacial deformities. The results are expected to provide high-level clinical evidence for the reliability of patient-specific appliances in orthognathic surgery.

Accuracy assessment through three-dimensional superposition of the post-operative volumetric CT and the digital therapeutic project files.

"Dentofacial deformity refers to deviations from the norm of facial proportions and tooth ratios of such magnitude as to represent a disability." \[1\] These conditions afflicted two aspects of the patient's health: the first related to the functions performed by the stomatognathic apparatus (mastication, swallowing, phonation, etc...), the second related to the morphology of the face, which--by virtue of the severe disharmony of its parts--did not fully realize its function as an organ of relationships, leading the patient to high levels of psychological distress. The nature of the dentofacial deformities was mainly related to skeletal discrepancies between the maxillae, such that the malocclusion could not be resolved by orthodontic treatment alone. The resolution of these conditions required a perfect synergy between orthodontic therapy (aimed at dental alignment of the individual arches) and surgical therapy (aimed at morphological harmonization of the face and obtaining the correct occlusion).

Dentofacial deformities refer to morphological anomalies of the jaws. Their development during growth determines the shape of the lower third of the face and the type of dental occlusion. A maxillo-mandibular dysmorphosis associates morphological modification of the face and anomaly of the occlusion. If these anomalies are most often hereditary, they also depend on acquired factors such as swallowing, breathing, sucking or phonation disorders. Angle's classification defines three classes of dental occlusion: class I, when the ratio between the maxillary and mandibular first molars is normal, class II when the upper molar is too far forward, and class III when it is too far back. Class II and III dysmorphoses can result in an alteration of the masticatory function, pain (TMJ, headaches) or sleep apnea. At the same time, they cause patients to experience a decrease in self-esteem, anxiety and social discomfort. Class II and II usually require orthodontic treatment and orthognathic surgery to correctly align the jaws. This surgery has a positive impact on the dental occlusion and the functions concerned, but also on the facial morphology, all of which often leads to an improvement in the patient's quality of life. Standardized photographs presenting control subjects (class I) and patients (class II and class III) before and after surgery will be included in an approximately 10 min video sequence. Naive participants will look at this sequence during which the faces of the controls and the patients - before and after surgery - will alternate, with the instruction being free visual exploration of the images. The total fixation durations in defined areas of interest (eyes, nose, mouth, chin) will be recorded with an eye tracking device and the results will be processed using a dedicated software.