A midline shifted sideways is usually invisible to everyone but the dentist; a midline that is tilted is spotted immediately, even by people who cannot say why.
The millimetres that decide are the tilted ones, not the shifted ones, and clinically the two behave very differently. A dental midline sitting one or two millimetres to the left or right of the facial midline is tolerated by the eye and routinely goes unnoticed in photographs. The same two millimetres expressed as a tilt, with the contact line between the central incisors leaning rather than standing vertical, is caught instantly, because the brain compares it against the vertical of the face and the horizontal of the eyes. Correcting tilt therefore takes priority over correcting position.
The facial midline runs through the bridge of the nose and the centre of the philtrum, and it is not always the same as the centre of the chin, which can be skeletally deviated. The incisal plane should sit parallel to a line drawn between the pupils, not parallel to the floor. All of this is assessed on photographs taken in natural head position, standing and looking at the horizon, rather than lying back in a dental chair where the head is tipped and every reference moves.
Ceramic can move an apparent midline by roughly one to two millimetres through width adjustment and careful line-angle placement, and it can level a mild tilt. Beyond that the correction has to come from moving the teeth: orthodontics from 1,400 EUR, or in skeletal cases from surgery. We will not disguise a four-millimetre skeletal deviation with crowns, because doing so means grinding the teeth on one side far more aggressively than on the other to fake symmetry.
Ask for a full-face photograph at full smile with a vertical line drawn through the facial midline and a horizontal line through the pupils. Look at the mock-up standing up, in daylight, with the mirror held at arm's length rather than close to your face. If the design is right, nothing should pull your eye to one side. A twenty-unit smile in monolithic zirconium starts from 180 EUR per tooth, and the design work behind those lines is included.
The nose and philtrum, in almost every case. Chins are frequently deviated by a few millimetres for skeletal reasons, and matching the teeth to a deviated chin transfers that asymmetry to the most visible part of the face.
Not on its own. A midline that moves between rest and biting means the jaw is being displaced by the bite itself, and that has to be diagnosed before any ceramic is planned, otherwise the new crowns simply lock the displacement in place.