Intraoral Scanners in Modern Dentistry

Imaging Technology

Different scanner brands use different optical methods. Some project a grid of structured light onto the teeth and measure how the grid distorts. Others use confocal microscopy or active wavefront sampling. Despite these differences, the goal is the same: a high-resolution 3D model.^[2]

Scanning speed and accuracy have improved over the past decade. Newer scanners produce color models and can capture full arches in a few minutes, though accuracy still depends on operator technique and the quality of the soft tissue capture.^[2][4]

Scan Strategy and Path

Research has shown that the path the clinician follows during scanning can influence the final accuracy, particularly for full-arch impressions. An in vitro study by Ender and colleagues, which tested eight intraoral scanners on a full-arch master model, found measurable differences in trueness and precision based on the scan sequence used.^[1]

For implant cases, the position and angle of the scan body (a small marker placed on the implant) also affects accuracy. Studies have found that factors like scan body angulation and inter-implant distance can shift the measured implant position, which matters for the final fit of the prosthesis.^[3]

Implant Planning and Surgical Guides

For dental implants, scanners capture the surface of teeth and gums, which is then merged with a CBCT scan of the underlying bone. This combined data lets the surgeon plan implant position virtually and print a surgical guide that directs the drill during surgery.^[7]

After implant placement, scanners are also used to capture the position of the implant for the final crown or bridge. Research suggests accuracy can vary based on the number of implants, the spacing between them, and scan body angulation.^[3]

Crowns, Bridges, and Same-Day Restorations

Scans are used to design crowns, inlays, onlays, veneers, and bridges. When paired with a chairside milling unit, some restorations can be made and seated in one visit. For crowns and short-span bridges, accuracy of intraoral scanning is generally comparable to conventional impressions.^[2][4]

Orthodontics and Occlusion

Clear aligner therapy starts with a digital scan that is used to plan tooth movement and 3D-print or thermoform a series of trays. Scanners also support analysis of bite (occlusion) and jaw relationships when combined with other digital tools.^[5]

What the Research Shows

A 2022 systematic review by Al-Hussaini and colleagues concluded that intraoral scanners produce clinically acceptable accuracy for single units and short-span restorations, with reduced accuracy as the scan span increases. The authors noted that full-arch scans show greater deviation from the true reference than short-span scans, especially in cases without enough fixed landmarks.^[2]

A 2023 in vitro study by Borbola and colleagues compared an intraoral scanner against five desktop scanners and an industrial reference scanner. The intraoral scanner was less accurate than the industrial scanner but performed within clinically useful limits for most prosthodontic indications.^[4]

An earlier 2018 study in the Journal of Orthodontics by Porter and colleagues compared intraoral and extraoral (model) scanners on digital articulation. Both produced reproducible results, with small differences depending on the workflow used.^[5]

Some research findings on full-arch and implant accuracy are mixed. Some studies report clinically acceptable error within 50 to 100 microns, while others document deviations that could affect the seating of long-span prostheses. Evidence is still evolving, so your specialist may use a conventional impression as a backup for complex cases.^[1][3]

Regulatory Status

Intraoral scanners marketed in the United States are FDA-cleared as medical devices. FDA clearance, granted through the 510(k) pathway, indicates substantial equivalence to a previously cleared device. This is different from FDA approval, which is reserved for higher-risk products through the premarket approval (PMA) pathway. You can verify any specific scanner system in the FDA's public 510(k) database.^[6]

Advantages

Patients typically report greater comfort with digital scanning compared to conventional impression materials, especially those who gag easily. Scans can be paused, rescanned in sections, and reviewed instantly on screen.^[2]

Digital files can be sent to laboratories or design software within minutes. This often shortens the time from impression to finished restoration and reduces the chance of errors during shipping or pouring stone models.^[2]

• No impression trays or putty in many cases
• Real-time visualization of the scan
• Easier to capture children, anxious patients, and those with a strong gag reflex
• Direct integration with implant planning and milling software

Limitations

Accuracy can decrease for full-arch scans and in cases without teeth (edentulous arches), where there are fewer landmarks for the software to stitch images together. Research suggests that accuracy in implant-treated edentulism depends on scan body angulation and position.^[2][3]

Highly reflective surfaces, such as polished metal restorations, can interfere with optical scanning. Heavy bleeding or excess saliva can also reduce scan quality. In some cases, your specialist may still recommend a conventional impression. Operator training and the chosen scan path also influence the final result.^[1]

• Reduced accuracy for full-arch and edentulous cases
• Reflective metals and moisture can disrupt capture
• Equipment cost may limit availability in some practices
• Operator experience and scan strategy affect results

Insurance and Billing

Dental insurance generally pays for the underlying procedure (the implant, crown, or appliance), not for the scanning technology itself. Ask your provider for a written estimate that lists the procedure codes, what is covered, and your expected out-of-pocket cost. Costs vary by location, provider, and case complexity.