Both disorders of the stomatognathic system and body posture defects concern an increasingly younger population in Poland and in the world. The scale of both problems is constantly increasing. Structural and functional disorders in the area of the stomatognathic system have begun to be known as a disease of modern civilization. Bite defects immediately after tooth decay are the second most common dental problem for children around the world. The scale of the problem according to some sources makes up 75% of this population. Similarly, in the case of body posture defects in the spine, lower limbs and feet, it is estimated that they are present in up to 60-70% of Polish children. The critical period for the development of defects in both posture and the orofacial area falls at the same age, i.e. early school and puberty. Despite of the extensive literature describing both issues, there is still no clear and objective scientific evidence that would confirm the correlation of the two phenomena.~The presented project is an original cross-sectional study. A 400 school-age children between 6 and 15 years of age will participate in the study. Research will be conducted in randomly selected orthodontic clinics and primary schools.~The subjects will be divided into subgroups: a) children with correct body posture and without stomatognathic system dysfunction; b) children with a diagnosis of body posture defect; c) children with a diagnosis of malocclusion; d) children with a stomatognathic system dysfunction. After obtaining the mandatory written consent of the parent and child, the child's medical qualification to participate in the study will include the exclusion of: congenital structural defects of the spine, chronic diseases of the nervous system, genetic diseases, neuromuscular dystrophy, endocrine disorder, an ongoing contagious disease, present locomotor fracture, current muscular injury. The inclusion criterion will include: age of study participant from 6 to 15 years of age, in case of an existing defect in body posture/or malocclusion/or dysfunction of the stomatoghnatic system, lack of specific causes.~Methods~interview based on standardized questionnaires, i.e. Research Diagnostic Criteria of Functional Disorders of the Masticatory System BKD / ZCURNŻ~Polish version, TMD Questionnaire, Neck Disability Index, International Physical Activity Questionnaire (IPAQ) (short version), Questionnaire on Food Related Behavior (KZZJ)~clinical examination of the stomatognathic system (structural and functional), using JMA+ Analyser (Jaw Motion Analyzer) to analyse movement and function of the temporomandibular joints, mandibular position, condyle position (EPA), and access the muscle action potentials through bipolar skin surface electrodes EMG, assessment of occlusion by visual method according to Angle classification.~comprehensive 3D examination of the body posture (static and dynamic) in the area of the spine, lower limbs and feet, performed by photogrammetric method (4th Generation MORA) and non- invasive image acquisition technology with the aid of infrared (Kineod) and The CQ Elektronik system.~functional assessment of the spine and lower limbs mobility trough a wireless motion sensor Moover.~complementary tests, i.e. anthropometric measurements (height, weight, waist and hip circumference, skin folds), foot pressure on the ground and body balance accessed by pedobarograph FreeMed, body mass components measured by the Tanita MC 980 MA (BIA method), evaluation of 7-days of physical activity by accelerometer ActiGraph GT3X-BT, blood pressure measurement by Medel Connect Cardio MB 10 monitor.
The aim of the study is to demonstrate a correlation between body posture and the structure and function of the stomatognathic system in school-age children.