When breastfeeding is difficult or impossible during the neonatal period, an analysis of muscle activity can help determine the best method for substituting it to promote the child’s development. The aim of this study was to analyze the electrical activity of the masseter muscle using surface electromyography during suction in term newborns by comparing breastfeeding, bottle and cup feeding. An observational, cross-sectional analytical study was carried out on healthy, clinically stable term infants, assigned to receive either breast, or bottle or cup feeding. Setting was a Baby Friendly accredited hospital. Muscle activity was analyzed when each infant showed interest in sucking using surface electromyography. Root mean square averages (RMS) recorded in microvolts were transformed into percentages (normalization) of the reference value. The three groups were compared by ANOVA; the “stepwise” method of the multiple linear regression analysis tested the model which best defined the activity of the masseter muscle in the sample at a significance level of 5%. Participants were 81 full term newborns (27 per group), from 2 to 28 days of life. RMS values were lower for bottle (mean 44.2%, SD 14.1) than breast feeding (mean 58.3%, SD 12.7) (P = 0.003, ANOVA); cup feeding (52.5%, SD 18.2%) was not significantly different (P > 0.05). For every gram of weight increase, RMS increased by 0.010 units. Masseter activity was significantly higher in breastfed newborns than in bottle-fed newborns, who presented the lowest RMS values. Levels of masseter activity during cup-feeding were between those of breast and bottle feeding, and did not significantly differ from either group. This study in healthy full term neonates endorses cup rather than bottle feeding as a temporary substitute for breastfeeding.

Muscle electrical activity analysis can aid in the identification of oral motor dysfunctions, such as those resulting from an altered lingual frenulum, which consequently impairs feeding. Here, we aim to analyze the suprahyoid muscle electrical activity of infants via surface electromyography, based on lingual frenulum attachment to the sublingual aspect of the tongue and floor of the mouth during breastfeeding. In the present study, we have studied full-term infants of both genders, aged between 1 and 4 months old. The mean muscle activities were recorded in microvolts and converted into percent values of the reference value. Associations between the root mean square and independent variables were tested by one-way analysis of variance and Student’s t-test, with a significance level of 5% and test power of 95%, respectively. We evaluated 235 infants. Lower mean muscle electrical activity was observed with the lingual frenulum attached to apex/lower alveolar ridge, followed by attachment to the middle third/lower alveolar ridge, and between the middle third and apex/lower alveolar ridge. Greater suprahyoid muscle activity was observed with lingual frenulum attachment to the middle third of the tongue/sublingual caruncles, showing a coordination between swallowing, sucking, and breathing. Surface electromyography is effective in diagnosing lingual frenulum alterations, the attachment points of which raises doubt concerning the restriction of tongue mobility. Thus, it is possible to identify oral motor dysfunctions.

Introduction Muscle electrical activity analysis can aid in the identification of oral motor dysfunctions such as those resulting from altered lingual fraenulum which, in turn, impairs feeding. We aimed to analyse suprahyoid muscle electrical activity of infants based on lingual fraenulum attachment to the sublingual (ventral) aspect of the tongue and floor of the mouth, during breastfeeding. Methods and Results We studied full-term infants of both genders aged between 1–4 months. Lingual fraenulum evaluation and surface suprahyoid muscle electromyography was performed during breastfeeding. Mean muscle activities were recorded in microvolts and converted into percent values (normalisation) of the reference value. Associations between root mean square and independent variables were tested by one-way analysis of variance and Student’s t-test with significance level of 5% and test power of 95%. We evaluated 235 infants while breastfeeding. The lingual fraenulum was commonly attached to the tongue’s ventral aspect between middle third and apex, and on the mouth floor visible from the lower alveolar ridge. Lower muscle activity was observed with lingual fraenulum attached to apex/lower alveolar ridge, followed by attachment to middle third/lower alveolar ridge, and between middle third and apex/lower alveolar ridge. Highest activity observed in Infants with attachment to middle third/sublingual caruncles, had a thin lingual fraenulum, performed several sucks followed by short pauses, showed coordination between swallowing, sucking, and breathing, did not “bite” nipple, and showed no tongue snapping nor stress. Conclusion Greater suprahyoid muscle activity during breastfeeding was observed with lingual fraenulum attachment to middle third of the tongue/sublingual caruncles, showed coordination between swallowing, sucking, and breathing. Surface electromyography is effective in diagnosing lingual fraenulum alterations, whose attachment point raises doubts as restriction of tongue mobility. This technique identifies possible oral motor dysfunctions, enables direct therapeutic interventions and early intervention, and prevents feeding and communication alterations. ²²