Guide · Shade and esthetics
Diagnostic mock-up: how to try in the wax-up
How to make a mock-up from the wax-up with a silicone index and bis-acryl, check esthetics, speech and function, and what to send the lab for the wax-up.
Short answer
A diagnostic mock-up is a copy of the diagnostic wax-up in bis-acryl, carried to the mouth by a silicone index with no prep. It lets you and the patient judge form, length, speech and function before any reduction. In bench studies, mock-ups came out larger than the wax-up, most of all in the incisal third.
Step by step
- 01
Order the wax-up with a written goal
Send the lab scans of both arches, the bite, smile and face photos, and what should change on each tooth. It's done when the Rx says which teeth, how much length and what shape.
- 02
Make the silicone index on the wax-up model
Take the index off the wax-up model with heavy- and light-body addition silicone, or with clear silicone, backed by a rigid tray. It's good when it copies the incisal edges and embrasures with no bubbles.
- 03
Trim the index at the gingival margin
Cut the facial flange back to the gingival margin and notch the palatal side of the index. Try the empty index in the mouth: it has to seat without rocking, resting on the teeth that don't change.
- 04
Prepare the teeth without etching
Clean and dry the teeth with a lip retractor and cotton rolls. No etch, no bonding agent: the mock-up has to come off in one piece after the try-in.
- 05
Load the index with bis-acryl and seat it
Inject bis-acryl only into the teeth that change, keeping the mixing tip buried to avoid bubbles, and seat the index with firm pressure. Hold it still for the set time in the material's instructions for use.
- 06
Remove the index and the flash
Lift the index along its path of insertion and clear the flash at the cervical areas and embrasures with a blade or explorer without dislodging the mock-up. Check the incisal third: it's where the copy strays most from the wax-up.
- 07
Check esthetics, speech and function
Look at the incisal edge with the lip at rest and in a smile, the midline and the incisal plane against the face. Listen to speech, especially F, V and S sounds, and check protrusive and lateral movements.
- 08
Photograph and record the approved mock-up
Repeat the opening photos, with retractors, lip at rest and full smile, head in the same position. Scan the approved mock-up and tell the lab what changed from the wax-up.
What is a mock-up, and how is it different from a diagnostic wax-up?
A diagnostic wax-up is the design of the final tooth form, in wax on a model or in CAD on a scan. A mock-up is the same design taken to the mouth in resin for a try-in. The wax-up answers how much to add and where. The mock-up shows whether the result works in the patient’s face, speech and bite.
Villalobos-Tinoco and colleagues (Cureus, 2022) describe the usual route: a putty-and-wash silicone index taken off the wax-up is loaded with self-cure bis-acryl and seated in the mouth. With no prep, the try-in is reversible, so the patient can approve it, ask for changes or put treatment off.
A mock-up works for planning esthetic restorations in general, from a single tooth to a full arch. Ordering the wax-up and the printed trial restoration is covered on our diagnostic wax-up and mock-up page.
What should you send the lab for the wax-up?
To design the wax-up, the lab needs both arches, the bite, photos and what the patient wants changed. A scan shows the teeth. It doesn’t show the lip, the facial midline or the patient’s complaint, and that’s where the right length comes from.
| what to send | what the lab uses it for | without it |
|---|---|---|
| Scans of both arches, or stone models | the base of the design and the opposing arch | the design can’t check the occlusion |
| Bite registration | how the arches relate and how much room there is to add | length and volume with no occlusal reference |
| Smile photos: with retractors, lip at rest, full smile | incisal edge, lip line and buccal corridor | length comes from the model, not the face |
| Face photo | midline and incisal plane against the face | the plane can look level on the model and canted on the face |
| What the patient wants changed, tooth by tooth | the goal of the design | the lab has to ask before it can design |
| Signed prescription | identifies the order and who is responsible for it | the order is incomplete |
The three smile photos follow the protocol of Lassmann and colleagues (Clinical and Experimental Dental Research, 2026): retracted, lip at rest and full smile. Keep the head in the same position for all three so the images can be overlaid. Phone photos work in daylight with no filter; our shade and photo guide shows how to frame them.
The wording of the Rx matters as much as the files. “Close the diastema,” “add 1 mm to the centrals” and “keep the lateral incisor shape” are goals the lab can design to; “improve the smile” isn’t. Our scanning guide covers capturing both arches and the bite.
Analog or digital mock-up: what changes?
Analog and digital mock-ups differ in where the design starts and how it reaches the mouth; the clinical evaluation is the same. In the analog route, the technician adds wax to a stone model. In the digital route, the wax-up is designed in CAD on the scan, and the index comes off a printed model, or the mock-up is printed or milled straight from the design.
| step | analog | digital |
|---|---|---|
| Wax-up | wax added to a stone model | CAD design on the arch scans |
| Index made from | the waxed model | a printed model of the wax-up |
| How it reaches the mouth | bis-acryl in a silicone index | through a silicone index, or as a printed or milled shell seated on the teeth |
| Deviation from the design, on the bench | molded in an index: 0.047 mm on average (Cattoni, 2019) | milled PMMA: 0.011 mm on average (Cattoni, 2019) |
| Changes after the try-in | the wax is redone on the model | the approved mock-up is scanned and becomes the reference for the next design |
The comparison by Cattoni and colleagues (BMC Oral Health, 2019) is a bench study: 25 molded and 25 milled mock-ups, each group measured against its own wax-up. In the mouth, what matters most on either route is a well-supported index and well-cleared flash.
Why does a mock-up come out larger than the wax-up?
A mock-up comes out larger because the resin fills every gap between the index and the tooth, and any slack or flex in the index turns into thickness. In the three studies that measured thickness (Moldovani, Li and Ntovas), the molded mock-up was bulkier than the wax-up in every group; what changed was by how much.
| study | what it tested | what gave the closest copy |
|---|---|---|
| Moldovani et al. (2023) | six silicone and resin combinations, on 60 casts | clear silicone with a prefabricated tray and flowable composite; 92 Shore A lab putty with bis-acryl |
| Li et al. (2022) | index trimming and notches, on 72 indexes | trimmed to the gingival margin, with palatal notches |
| Ntovas et al. (2025) | four addition silicones, with and without a printed tray | index backed by a printed tray |
| Etienne and Nguyen (2021) | 20 mock-ups on the same patient | standard silicone in a rigid tray, better than hard silicone alone |
| Jin et al. (2025) | full arch in one step or two | two steps, alternating teeth: 0.15 mm mean deviation, against 0.31 mm in one step |
Moldovani and colleagues (The International Journal of Prosthodontics, 2023) found the incisal third least accurate and the middle third most accurate, and PMMA in the index the worst combination. In the clinical study by Etienne and Nguyen (The International Journal of Esthetic Dentistry, 2021), reproducibility was around 100 µm, which the authors considered clinically acceptable.
In practice, measure the try-in against the design, not by eye alone. If the mock-up will guide the prep, remember it carries that extra thickness.
Which mistakes make a mock-up misleading?
A mock-up misleads when the copy drifts from the wax-up, or when the evaluation looks at only part of the result. The mistakes below come from the accuracy studies and from what the try-in has to show.
| mistake | what happens | how to avoid it |
|---|---|---|
| Silicone index with no rigid backing | the index flexes on seating and the mock-up gets thicker | rigid or printed tray (Etienne, 2021; Ntovas, 2025) |
| Index not trimmed at the gingiva | resin on the gingiva and a bulkier facial | trim to the margin and notch the palatal side (Li, 2022) |
| Bubble in the index or the resin | a void at the incisal edge, where the copy is already least accurate | keep the tip buried in the resin; discard an index with a bubble |
| Flash at the cervical areas and embrasures | the tooth looks bigger and squarer than the design | clear it with a blade before evaluating |
| Full arch in a single step | larger deviation, mostly at the premolars | two steps, alternating teeth (Jin, 2025) |
| Judging only from the front, mouth open | length approved without seeing the lip at rest or hearing speech | lip at rest, smile, speech and excursions |
| Adjusting chairside without recording it | the restoration is designed on the old wax-up | photos and a scan of the approved mock-up on the case |
How do you evaluate a mock-up in the mouth?
Evaluate a mock-up for the face, then speech, then function, with the patient seated and then standing. In the reference cited by Lassmann and colleagues (2026), 1 to 4 mm of the maxillary central incisor shows with the lip at rest, depending on lip length and age.
For speech, F and V sounds rest the upper incisal edge on the lower lip, and S brings the anterior incisal edges close together. Pound (The Journal of Prosthetic Dentistry, 1977) used the S position as a reference for vertical dimension and for setting the anterior teeth. For function, check protrusive and lateral movements: a mock-up that interferes shows a length the bite won’t accept.
What do you do with an approved mock-up?
An approved mock-up becomes the reference for the case: photograph it, scan it and tell the lab what changed from the wax-up. Villalobos-Tinoco and colleagues (2022) prepped through the mock-up, with depth grooves that cut through the resin before they reach the tooth.
Etienne and Nguyen (2021) point out that, in a guided prep, the mock-up sets the restoration thickness, and an error in making it can lead to debonding and a weaker esthetic result. Because a molded mock-up is thicker than the design, a depth groove measured from it leaves less room for the restoration than planned.
Smile Digital Lab designs the wax-up in CAD on your scan, and the same design is printed as a trial restoration for the try-in. Whether you get a printed model or a silicone index for a chairside mock-up is agreed when the case is opened. Photos and the scan of the approved mock-up go into the case as files in the portal, with date, time and author; the portal screens are in Portuguese. The basics of the order are in our case submission guide.
Checklist before you approve the mock-up
- Wax-up ordered with a written goal, tooth by tooth
- Index backed by a rigid tray, trimmed at the gingiva, no bubbles
- Teeth clean and dry, no etch, no bonding agent
- Cervical and embrasure flash cleared before evaluating
- Lip at rest, smile, speech and excursions checked
- Three standardized photos and a scan of the approved mock-up on the case
Related services
Open a portal accountFrequently asked questions
Does a mock-up need any tooth prep?
No. The resin goes on clean, dry teeth with no etch and no reduction, and comes off in one piece. That's why a mock-up shows what the wax-up adds very well; where the design reduces a tooth, the tooth shows through the resin and that part of the try-in stays incomplete.
What material should I use for a mock-up?
Studies use self-cure bis-acryl in a silicone index. In Moldovani and colleagues' 2023 test, PMMA in the same index strayed furthest from the wax-up, while flowable composite in a clear index backed by a tray was among the most accurate.
Printed mock-up or chairside mock-up?
A printed or milled mock-up comes straight from the design, without a silicone index. In a 2019 bench comparison, milled mock-ups stayed closer to the design than molded ones (Cattoni and colleagues). A chairside mock-up can be adjusted on the spot. Smile Digital Lab prints the trial restoration from the wax-up.
Sources
- Additive wax-up and diagnostic mockup as driving tools for minimally invasive veneer preparations · Cureus (Villalobos-Tinoco et al., 2022)
- Accuracy of indirect veneer mock-up in comparison to diagnostic wax-up · The International Journal of Prosthodontics (Moldovani et al., 2023)
- Three-dimensional digital evaluation of thickness accuracy of mock-ups fabricated by silicone matrices: an in vitro study · Journal of Prosthodontic Research (Li et al., 2022)
- Impact of material and silicone index support using additively manufactured trays on the reproducibility of diagnostic trial restorations (mock-up): a comparative in-vitro study · Journal of Dentistry (Ntovas et al., 2025)
- Esthetic mock-ups: a clinical study of reproducibility · The International Journal of Esthetic Dentistry (Etienne and Nguyen, 2021)
- Effect of two-step mock-up methods on the trueness of complete-arch trial restorations: an in vitro study · BMC Oral Health (Jin et al., 2025)
- Milled versus moulded mock-ups based on the superimposition of 3D meshes from digital oral impressions: a comparative in vitro study in the aesthetic area · BMC Oral Health (Cattoni et al., 2019)
- A clinical algorithm for full-mouth rehabilitation in patients with generalized severe tooth wear: a case report · Clinical and Experimental Dental Research (Lassmann et al., 2026)
- Let /S/ be your guide · The Journal of Prosthetic Dentistry (Pound, 1977)
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