Digital wax-ups.
A diagnostic wax-up is the first physical statement of what a case is trying to achieve. Designed digitally, it can be printed, duplicated, revised and reused without starting again.
What a wax-up is actually for
Four things, and most practices use it for one. It tests whether the plan is achievable within the available space. It shows the patient what is proposed before anything irreversible happens. It generates a matrix for accurate provisionals. And it produces a reduction guide, so preparation is measured against the intended final contour rather than against the existing tooth.
That last use is the most valuable and the most often skipped. Preparing anterior teeth freehand and judging by eye is where most anterior compromises originate.
A wax-up that is only looked at and then set aside has delivered a fraction of its value.
Digital or by hand
A digital design can be revised without rebuilding, duplicated for multiple uses, stored indefinitely and reproduced exactly if a case is revisited years later. It also allows tooth proportions and symmetry to be measured rather than judged.
A hand wax-up remains excellent and some technicians work faster and more intuitively that way, particularly on complex full-mouth cases where the occlusal scheme is being developed rather than applied.
Either can be printed or duplicated in silicone for a matrix. The choice rarely matters to the practice — what matters is that the wax-up exists and is used.
Mock-ups and trial smiles
A wax-up converted to an intraoral mock-up, using a silicone matrix and a bis-acryl material, puts the proposal in the patient's mouth without preparing anything.
It is the single most persuasive thing available in aesthetic case discussion, and considerably more informative than any rendering. The patient sees the shape, the length and the lip relationship on themselves and can object while objecting is free.
It is also diagnostic for the clinician: phonetics, incisal display at rest and in a smile, and whether the proposed contour is achievable within the available space all become visible.
What the laboratory needs
Scans or impressions of both arches, an accurate bite record, and photographs — retracted frontal, close view, incisal edge and an unretracted smile showing the lip line.
Facial references matter more than they do for a single crown, because a wax-up is establishing tooth position relative to the face rather than relative to the adjacent teeth.
Tell us what the case is trying to achieve. Lengthen the centrals, close the diastema, level the incisal plane, increase the vertical dimension — a sentence of intent shapes the whole design.
Reusing the design
A digital wax-up is a file, which means it can be revised without rebuilding, duplicated for several purposes, and reproduced exactly years later.
That matters most on staged cases. A wax-up produces the reduction guide, the provisional matrix and the reference for the definitive restorations — three uses from one design, all consistent with each other.
It also means a case that stalls can be resumed. Where a patient defers treatment for a year, the design is still there rather than needing to be recreated from scratch.
Where a wax-up is worth the stage
Any anterior case involving more than one unit. Any case altering incisal edge position or vertical dimension. Full-mouth reconstruction, without exception. And any case where the patient's expectations need testing before treatment rather than after.
For a single posterior crown it is unnecessary. The threshold is roughly where the restoration stops reproducing what was there and starts proposing something different.
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Digital scans and conventional impressions are both accepted. Cases move by UPS and Purolator, and Fairmont works with practices throughout British Columbia and across Canada.