The remaining parties have scheduled a mediation session in a lawsuit involving a 20-year-old Tonganoxie High School graduate who suffered brain damage during a 2009 dental procedure in Lawrence.

An attorney for Lawrence oral surgeon Dr. Kirk Vincent said Friday that the parties — including the city of Lawrence and five other defendants — plan to attend a session with a mediator March 23.

“The goal is to address the positives and negatives of getting the case settled,” said Rick Merker, an Overland Park attorney who represents Vincent.

On Jan. 27, Douglas County District Judge Robert Fairchild approved a $3 million settlement in the case between the family of Austin Stone and Action Plumbing Inc. of Lawrence, which denied liability in the case. The plumbing company installed medical gas lines at Vincent’s office at 4811 Bob Billings Parkway.

The suit, filed on behalf of Stone and his guardians, alleges oxygen and nitrous oxide lines were crossed during design and construction of Vincent’s office at 4811 Bob Billings Parkway. Stone had visited the office to get four wisdom teeth removed by Vincent on March 30, 2009. The suit alleges he was injured and had to be hospitalized, according to the suit.

Stone was in a coma after the incident, and he is now legally blind and has other health issues.

The city is included as a defendant because the suit alleges inspectors should have caught the switch in the lines.

Other remaining defendants in the case are Vincent; Patterson Dental Supply Inc. of Topeka; Blanchard Design Group LLC of Lawrence, the project’s architect; general contractor Design Build Collaborative LLC of Lawrence; and mechanical engineers Hoss & Brown Inc. of Lawrence.