Augmented Reality in Oral Surgery

Augmented Reality-assisted Surgical Exposure of an Impacted Tooth

A digital workflow was used to assist the oral surgeon in pre-orthodontic exposure of a vestibular impacted canine using Augmented Reality.

Through software for the Object Recognition and Tracking, the researchers expand reality with cone beam computer tomography digital contents to optimize the outcome of surgery. The real-time video frames of the operating field aligned with the three-dimension file of the impacted tooth, were used as a guide to evaluate the surgical access to perform a minimally invasive flap and osteotomy.

This study evaluate an AR-assisted approach for surgical exposure of a maxillary impacted canine. The usual protocol is the following:

• Maxillary arches were scanned, and their occlusal relationship was registered using an optical intraoral scanner.The file was exported in Polygon File Format (PLY)
• Using open-source CAD software, the part of the upper arch was selected from the first premolar to the other first premolars The teeth, the incisal edges and the cusps of the anterior sector were the anatomical markers required to match the patient's mouth and perform the object recognition.To this file that corresponded faithfully to reality we added the digital information required, that is, the position of the impacted crown of the canine
• From the maxillary CBCT, DICOM files were imported in open-source medical software for segmentation and exportation of an STL file of the area of interest
• Two 3D files obtained were imported into a CAD-CAM design software for superimposition. 3D file consisting of the intraoral scan plus the endosseous position of the crown of the impacted canine was exported
• A full HD video camera was positioned in front of the patient's mouth, connected via an HDMI cable to a laptop
• The AR software was then started, and the video camera was associated as an input source The software recognizes edges of files in images transmitted from the camera and overlap the object to the video images.

Inclusion Criteria:

• Presence of an impacted tooth in aesthetic area
• Good health according to the System of the American Society of Anesthesiology
• No general medical contraindication for oral surgery
• Good periodontal health

Exclusion Criteria:

• Smoking more than 15 cigarettes a day • Untreated periodontitis
• Pregnancy
• Acute infections