Single-Visit Dentistry, Fully Realized

The second appointment is the most expensive thing in restorative dentistry that nobody puts on an invoice. It consumes a chair slot, a hygienist's coordination time, a lab courier, a temporary that may debond, and a patient's willingness to come back. Chairside CAD/CAM removes it entirely — and after four decades of clinical use, the question is no longer whether the technology works, but why any restorative practice would still design its schedule around waiting.

The hidden cost of the two-visit crown

Consider what a conventional crown actually requires. Impression material and trays. A provisional fabricated, adjusted, and cemented. A shipping cycle to the laboratory. A remake risk if the margin is unclear. A second block of chair time — plus the administrative overhead of booking it, reminding the patient about it, and absorbing the cost when they do not show.

• Chair time: two appointments instead of one, with setup and breakdown duplicated.
• Material waste: impression material, trays, provisional resin, temporary cement.
• Clinical risk: provisional debonding, marginal leakage, and tissue changes between visits.
• Patient friction: a second round of anaesthesia, travel, and time away from work.
• Unbilled labour: the coordination work that never appears on a fee schedule.

Every step you remove from a workflow is a step that cannot fail, cannot be rescheduled, and cannot be miscommunicated.

What the chairside workflow actually looks like

The modern chairside restorative pathway is deliberately short. Four steps, one appointment, no handoffs outside the operatory.

1. Scan

A powder-free intraoral scanner captures the preparation, the antagonist, and the bite registration in natural colour. The software builds a highly accurate 3D model within seconds and proposes the preparation margin automatically. Because the model is on screen immediately, the clinician can verify the preparation before the patient is dismissed — a quality gate that simply does not exist in the analogue workflow, where a deficient impression is discovered days later at the laboratory.

2. Design

Design software generates a biogeneric initial proposal, reconstructing the occlusal anatomy from the patient's remaining dentition rather than from a generic tooth library. The clinician refines contacts, contours, and emergence profile with shape and movement tools. On a cloud-connected platform this design step is location-independent — it can happen at the chair, at the front desk, or remotely.

3. Manufacture

The design is transmitted to the milling or grinding unit in the operatory. Production is fast enough to fit inside a single appointment: roughly two minutes for an inlay, around four minutes for a composite or hybrid ceramic crown in a high-speed grinding mode, and approximately five minutes for a zirconia crown in a super-fast milling mode.

4. Finalize

Materials requiring heat treatment are sintered and glazed chairside in a compact dental furnace with guided, material-specific programmes. The restoration is then tried in, adjusted, and definitively cemented — the same morning the patient walked in.

Materials have caught up with the ambition

Early scepticism about chairside restorations was largely a materials argument, and it was a fair one. That argument has aged badly. Validated chairside material classes now span zirconia, high-strength glass ceramics, hybrid ceramics, composites, and feldspathic ceramics. The clinician selects for the indication — strength for a posterior molar under heavy occlusal load, optical behaviour and polish retention for an anterior case — rather than accepting whatever the workflow allows.

The longevity evidence

Chairside CAD/CAM is one of the better-documented technologies in restorative dentistry, precisely because it has been in clinical service long enough to generate genuine long-term data rather than three-year proxies. The peer-reviewed literature includes long-term clinical evaluations by Reiss (Compend Contin Educ Dent. 2001;22(6 Suppl):14–18) and Reiss (Int J Comput Dent. 2006;9(1):11–22), a long-term assessment by Otto (Int J Comput Dent. 2017;20(3):315–329), and more recent work by Abdulrahman and colleagues (BMC Oral Health. 2021;21(1):625). Taken together, this body of evidence describes survival behaviour that stands comfortably alongside conventionally fabricated indirect restorations.

Where practices actually stumble

The technology is rarely the failure point. Adoption is. Three patterns recur:

1. Treating it as a device purchase rather than a workflow change. The unit arrives, the schedule does not change, and the practice keeps booking two-visit crowns out of habit.
2. Not delegating the scan. Intraoral scanning is intuitive enough to be delegated to trained auxiliary staff. Practices where only the dentist scans cap their own throughput.
3. Under-training on design. The first twenty designs are slow. The hundredth is not. Practices that abandon the workflow usually quit somewhere around the fifteenth.

A pragmatic starting point

The lowest-risk entry is not the full-arch reconstruction. It is the single posterior crown on a compliant patient with clear margins and uncomplicated occlusion — a case where the analogue alternative is well understood and the digital version can be benchmarked against it honestly. Run twenty of them. Measure appointment length, remake rate, and patient response. Then widen the indication set to inlays, onlays, veneers, and implant-supported single units.

The strategic point is not speed for its own sake. It is control. When scanning, design, and manufacture all happen under one roof, the clinician owns every variable that determines fit, contour, and shade — and owns the ability to correct them immediately rather than in three weeks.