Effects of lingual frenotomy on breastfeeding and electrical activity of the masseter and suprahyoid muscles.

PURPOSE: To analyze the effects of lingual frenotomy on the breastfeeding of infants, based on the electrical activity of the masseter and suprahyoid muscles and assessment of the breastfeeding. METHODS: Observational study developed between October 2017 and June 2018 with a sample of 20 newborns and infants who attended a dental clinic and were diagnosed with ankyloglossia. Another 20 were excluded for meeting some of the following exclusion criteria: babies more than 6 months old, who were not on exclusive or mixed breastfeeding, who had other clinical impairments that interfered with breastfeeding, who had other foods introduced into their diet, who had neurological changes and/or craniofacial deformities, and/or who did not finish all the stages of the study. Breastfeeding was assessed with the UNICEF Breastfeeding Assessment and Observation Protocol, while the muscle electrical activity was assessed with the Electrical Activity Assessment Protocol for the Masseter and Suprahyoid Muscles in Newborns During Breastfeeding. The same speech-language-hearing therapist conducted the two assessments both before the conventional frenotomy and 7 days after it. RESULTS: The signs suggestive of breastfeeding difficulties changed 7 days after the surgery, with a p-value </= 0.002 for general observation of the mother, position of the infant, latch, and sucking. The maximum voluntary contraction of the masseter was the only integral parameter with a difference, as the electrical activity had decreased. CONCLUSION: Behaviors favorable to breastfeeding increased 7 days after the frenotomy in all the breastfeeding assessment categories, whereas the electrical activity of the masseter decreased.