Lawsuit Filed After Child’s Death Following Dental Anesthesia

A medical malpractice lawsuit has been filed by the mother of Silvanna Moreno, a 9-year-old girl who tragically died following dental surgery at Dreamtime Dentistry in Vista, California. The lawsuit, filed on December 29, 2025, in the California Superior Court in San Diego, alleges that errors in anesthesia administration and post-operative monitoring led to silvanna’s death [1].

The Events Leading to Silvanna’s Death

according to the lawsuit, silvanna underwent a dental procedure on March 18, 2025, at Dreamtime Dentistry administered by Dr. Ryan Watkins, with the procedure performed by dr. Kyung Lee Boen. Following the procedure, Silvanna was monitored in the recovery room for approximately 45 minutes before being discharged to her mother, Itzel de Jesus [1].

De Jesus reported that upon discharge, Silvanna appeared to be in a severely somnolent state, described as “comatose-like,” and unsuitable for release. after being taken home, Silvanna’s brother discovered she had stopped breathing a few hours later. Paramedics were instantly called, but Silvanna was pronounced dead at a local children’s hospital shortly thereafter [1].

Cause of Death: Methemoglobinemia

The San Diego County Medical Examiner determined the cause of death to be methemoglobinemia, a rare blood disorder that impairs the blood’s ability to carry oxygen [1]. Methemoglobinemia can be caused by certain medications and, in Silvanna’s case, was linked to the administration of nitrous oxide during the dental procedure. Contributing factors included several other medications administered during the procedure,including dexamethasone,glycopyrrolate,hydromorphone,isoflurane,ketorolac,midazolam,ondansetron,propofol,and sevoflurane [1].

Understanding methemoglobinemia

Methemoglobinemia occurs when iron in hemoglobin – the oxygen-carrying molecule in red blood cells – is oxidized,making it unable to effectively bind to and release oxygen. Symptoms can range from mild bluish skin discoloration to severe,life-threatening oxygen deprivation. Prompt diagnosis and treatment, including oxygen supplementation and administration of methylene blue, can effectively reverse the condition [2].

Allegations in the Lawsuit

The lawsuit alleges that the dentists and the dental practice failed to properly monitor Silvanna after the procedure and prematurely discharged her while she was still substantially affected by the anesthesia. It further claims that a timely diagnosis of methemoglobinemia, followed by appropriate treatment, coudl have prevented her death. [1]

Video surveillance reportedly showed an unconscious Silvanna being wheeled and carried into her mother’s vehicle, and a physician at the hospital noted that her state was “entirely too somnolent to be discharged” [1].

Ongoing Legal Proceedings

The lawsuit seeks compensatory damages, as well as legal expenses. Dreamtime Dentistry and the named dentists have not yet publicly commented on the allegations. This case underscores the critical importance of vigilant post-operative monitoring and prompt intervention in cases of suspected complications following anesthesia administration. The case is ongoing as of January 8, 2026.

Finding Quality Dental Care in St. Louis

If you’re seeking dental care in the St. Louis area, it is vital to prioritize practices with a strong focus on patient safety. South St.Louis Dental Group specializes in a variety of procedures, including implants and cosmetic dentistry [3] while STL Urgent Dental provides emergency dental care with expanded hours [4].When choosing a dentist,consider factors such as board certification,patient reviews,and the practice’s commitment to using current safety protocols.