The bubbly laughter of 9-year-old Silvanna Moreno still echoes through Sherman Elementary’s hallways, where teachers and classmates struggle to comprehend how a simple dental visit could end so tragically. The San Diego girl developed methemoglobinemia after receiving nitrous oxide during a procedure, a complication so rare most dentists may never encounter it in their careers.
Silvanna’s grandmother became alarmed when the normally energetic child slept unusually long after returning home. By the time paramedics arrived, her heart had stopped. Medical experts explain that methemoglobinemia essentially suffocates victims from within, as their blood loses the ability to deliver oxygen – sometimes without obvious warning signs.
The dental team maintains they followed all safety protocols, noting Silvanna showed perfect oxygen levels throughout the procedure. But for her devastated mother and three siblings, these explanations provide little comfort as they face life without Silvanna’s contagious smile and spontaneous hugs.
🇺🇸 A nine-year-old girl died after going to a San Diego dentist's office for a routine surgery. Silvanna Moreno had dental surgery under anesthesia at Dreamtime Dentistry on March 18. According to the practice website, Dr. Ryan Watkins is the only dentist listed who is trained in… pic.twitter.com/drGAtKbzu7
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