Electromyographic analysis of the stomatognathic system of children with Molar-incisor hypomineralization

Abstract

Introduction Molar-incisor hypomineralization (MIH) is a qualitative defect of dental enamel that affects one or more permanent first molars, with or without involvement of the incisor teeth. This condition leads to challenges to dental care and treatment planning. Aim Based on the hypothesis that children who have MIH possibly present alterations in postural and masticatory activities and considering the absence of studies investigating these parameters, the present study evaluated the functionality of the stomatognathic system considering the mentioned aspects. Materials The comparison of individuals with (MIHG; n = 32) and without MIH (CG; n = 32) was evaluated by electromyographic activity of the masseter and temporal muscles (right and left), as well as evaluation of the masticatory cycles during habitual mastication. Results MIHG showed muscle hyperactivity in postural and dynamic conditions compared to the CG; higher electromyographic values for MIHG when compared to CG in the following postural conditions: at rest for the right temporal (p = 0.00) and left temporal muscles (p = 0.03); in the protrusion to the right temporal muscle (p = 0.02); in the right laterality for the right masseter (p = 0.00) and left temporal muscles (p = 0.01); in the left laterality for the right masseter (p = 0.03) and left temporal (p = 0.04) muscles. In dynamic conditions with consistent food, significance was observed for the left temporal (p = 0.01); and with soft food for the right (p = 0.01) and left temporal muscles (p = 0.04). Conclusions Children with MIH seem to have impaired functionality of the stomatognathic system. Children with MIH have alterations in the stomatognathic system.

Children with Unilateral Molar-Incisor Hypomineralization May Exhibit Contralateral Muscle Hyperactivity

“…Thus, it is suggested that this may have possibly occurred due to the severity of the disease not being severe enough to resist using the affected side. When this enamel anomaly presents a higher degree of hypersensitivity or fracture, children tend not to use the affected side, but rather the other side for comfort in both biting and chewing [20,49].…”

“…Clinical consequences associated with MIH include hypersensitivity [2,[11][12][13], di culty in achieving anesthesia [14,15], and negative aesthetic impacts [16][17][18]. Fractures after tooth eruption and rapid caries progression in newly erupted rst permanent molars may occur [19], predisposing the patient to chewing preference and leading to stomatognathic system alterations [20].…”

“…Lesions in different dental groups can cause stomatognathic system alterations, potentially progressing to temporomandibular dysfunctions [20]. In bilateral enamel defects, these alterations can be severe enough to considerably interfere with masticatory functions and may compromise the stomatognathic system [20].…”

“…Lesions in different dental groups can cause stomatognathic system alterations, potentially progressing to temporomandibular dysfunctions [20]. In bilateral enamel defects, these alterations can be severe enough to considerably interfere with masticatory functions and may compromise the stomatognathic system [20]. Since MIH clinically presents heterogeneously and asymmetrically in most cases [10], even affecting only one rst permanent molar, there was interest in discovering the behavior of each side of the child's dental arch.…”

Unilateral Molar Incisor Hypomineralization influences the chewing side? An observational study in children

“…Different methods for evaluating chewing patterns have been proposed, some aiming to study functionality and chewing e ciency, while others assess issues related to chewing dynamics. In the rst group, studies stand out that use surface electromyography, devices measuring bite force, and technologies allowing evaluation of jaw movements and/or occlusal dynamics [7,36,8,9,37]. Research related to dynamics include the assessment of chewing performance, quanti cation of dental functional units, and the PCS [38,13,[39][40][41].…”