Tragic Loss: 9-Year-Old Girl Dies Following Routine Dental Procedure in California
What was meant to be a routine dental visit ended in heartbreak for the Moreno family, as 9-year-old Silvanna Moreno tragically passed away just hours after undergoing a procedure at Dreamtime Dentistry in Vista, California on March 18, 2025.
According to the San Diego County Medical Examiner’s Office, Silvanna’s death was ruled an accident, caused by methemoglobinemia — a rare condition in which an abnormal amount of methemoglobin in the blood hinders the body’s ability to carry oxygen. The condition developed in the context of recent nitrous oxide administration, commonly known as “laughing gas,” used for sedation during dental treatments.
Silvanna had reportedly taken children’s Tylenol the day before her appointment. During the three-hour visit, she underwent a root canal and multiple tooth extractions, including one decayed permanent tooth. Dreamtime Dentistry stated that Silvanna was a new patient, referred for extensive treatment, and had been evaluated as a suitable candidate for outpatient general anesthesia.
Dr. Ryan Watkins, the anesthesiologist on duty, said Silvanna had a history of regular medical checkups and showed no signs of underlying health conditions that would have precluded anesthesia.
Following the procedure, Silvanna was taken to a recovery room, where her mother noted that she appeared extremely drowsy, occasionally opening her eyes and mumbling. At home, she continued to sleep. When her breathing suddenly slowed and she became unresponsive, her family called 911. Despite emergency efforts, Silvanna was pronounced dead at the hospital shortly after.
Dr. Watkins later issued a statement expressing the clinic’s sorrow:
Silvanna’s passing has renewed concerns about the rare but serious risks of sedation in pediatric dentistry. Experts emphasize the importance of careful patient screening, dosage precision, and post-procedure monitoring in reducing such incidents—particularly with young patients.
The community continues to mourn the sudden loss of a vibrant young life, as Silvanna’s story brings attention to both the medical complexity and emotional weight behind pediatric dental care decisions.
