Diagnostic Wax Ups and Mock-Ups in Comprehensive Esthetic Treatment

Initially before any treatment held on, it is crucial to fully understand the patient’s chief complain and his/her desire from seeking a dental treatment in order to fulfill them. The success of treatment mainly relies on the patient’s satisfaction; therefore it is only possible through engaging the patient in decision-making process by visualizing the planned result in a 3D- wax-up and mock-up.

Wax-up is a diagnostic procedure done by a well-trained and skilled dental technician, were the potential treatment outcome is built in wax on the study cast before treatment. When this wax model be replicated intra-orally by the aid of silicone indexes and auto polymerizing resin over the unprepared teeth, this clinical duplication of lab work is called: “diagnostic mock-up” or “ diagnostic template”.

Diagnostic mock-up is an easy, rapid procedure that gives us an instant feedback prior to treatment. It is considered a productive way of communication between the patient, dentist and the lab technician (ceramist). Also, mock-up allows the patient to be involved in treatment planning which leads us to gain the patient’s confidence. Since the patient had the opportunity to express his/her own thoughts regarding the dentist’s treatment plan they will be highly cooperative in treatments that require long or multiple appointments and they’ll also feel responsible of the end result that they have chosen. Even mock-ups help in controlling the time and money by avoiding the repetition of steps especially the final result. In addition, seeing the desired changes clinically in a reversible manner allow the dentist to test the patient’s rest and smile position, occlusion, verify the contour, angulation, length, shade of teeth and phonetics.

Diagnostic wax-up can be used for diagnosing and planning the treatment of dentate patients, partially edentulous patients, and completely edentulous patients by setting the denture teeth or waxed teeth in a wax media. Wax-up can also be utilized as a treatment tool as forming radiographic and surgical implant placement guide in edentulous spaces, or forming a matrix to be used as a guide for amount of reduction during teeth preparation or for creating provisional restorations.

Techniques:

There are three ways of preparing the diagnostic mock-up:

A) “ Preliminary diagnostic mock-up” or “ free hand direct mock-up in composite”

B) “Secondary diagnostic mock-up” or “ mock-up according to the wax-up with self curing resin”

C) “CAD/CAM” or “ modern digital design mock-ups” or “ computer imaging simulation”.

“ Preliminary diagnostic mock-up” or “ free hand direct mock-up in composite”

This is a simple chair sided technique which is done at the initial appointments using an un-cured composite resin. It is totally reversible mock-up procedure were teeth are not etched nor bonded to the restoration.

Simply, composite resin, restorative material, with some degree of shade matching is contoured on the teeth intra-orally according to the planned shape and position of teeth. Then mock-up is evaluated while it’s still malleable in different lip position, phonetics, assessing the degree of integration with the face and lips. After adjustments are performed, composite is polymerized “ cured”. Next, photographs and impressions are taken to document the new smile design. Finally, composite mock-up is easily flacked off and sent to the lab along with the cast as a guide for the wax-up.

The main disadvantage of this mock-up technique is it’s high cost of composite specially if it’s used frequently. Also, some sort of difficulty is faced for quickly contouring the composite.

Save your time!
We can take care of your essay

• Proper editing and formatting
• Free revision, title page, and bibliography
• Flexible prices and money-back guarantee

Place Order

“Secondary diagnostic mock-up” or “ mock-up according to the wax-up with self curing resin”

On the other hand, the second technique, which is used to form the mock-up, is by making an impression using an irreversible colloid impression then pouring it to get the positive replica of the teeth. By the aid of the articulator the casts are then mounted according to the face bow record. Next, the wax-up is built, taking into consideration all needed elements in a smile design, such as: gingival zenith, gingival architecture, teeth shape, proportion, axial inclination and embrasures.

Once the dentist and the patient are satisfied with the wax-up, then it’s time to review it intra-orally. From the wax-up we create a matrix using either Polyvinyl Siloxane putty material to form what is called “ silicone key” or fabricating “ vacuum –formed splint”.

On the patient’s teeth and surrounding gingiva we place a layer of petroleum jelly then it’s thinned with air, for the ease of removal afterwards. According to the period of time that the dentist wants the mock-up to stay in the patient’s mouth, the selection of the material relies. In case the mock-up is needed to be left home with then we fill it with a long standing material such as stained linked acrylic resin or if it’s made to be tried for a short period in the clinic as most cases, then we fill the matrix with “ flowable composite” or “auto-cure resin”.

The matrix is placed on the patient’s teeth until it’s fully polymerized. Excess material is trimmed form the gingival margins. Immediately the patient will able to see the proposed result and the clinician will have the opportunity to assess the contour of the restoration, along with length and inclination of teeth, occlusal plan, teeth relation with the upper and lower lips at rest and smile positions, phonetics, and the relation of the patient’s face with the teeth shape overall. At the end, simply a hand instrument detaches the mock-up.

“CAD/CAM” or “ modern digital design mock-ups” or “ computer imaging simulation”.

The classical way of providing a diagnostic wax-up and mock-up prior to the treatment in which wax-up is transferred to the patient’s mouth by the aid of silicone index and auto-polymerizing resin is time consuming and produces only one version of the treatment outcome. Therefore, digital smile design (DSD) has been provided to overcome the disadvantage and limitations of the classical method.

Recently many practitioners are shifting from the conventional method to the use of virtual technology, since what we all aim to regarding: providing the standard care for patient, reduction of operator’s errors are all achievable. Computer-aided design (CAD) and computer aided manufacturing (CAM); made it easier for both dentist and technician, reduced the time spent in the clinic and laboratory, improved the final mock-up accuracy and reproducibility and produces a very high terminal esthetic result. In addition, the software tools offer various tooth shapes according to the size, patient’s age, phenotype. Also, digital smile design (DSD) considers certain important facial reference plane for manipulating the design. A further benefit is the possibility to modify the initial design and to freedomly generate multiple future restorations in a skillful way.

On the other hand, there are some shortcomings of using DSD such as: the waste of considerable amount of material, being unable to establish a geometry which lies bellow the milling bur diameter and the difficulty of producing a mass component. Even, initially economic investment is needed to purchase the hardware also time and effort is needed to master the work with the design software.

Beside this, correct digital planning requires precise photographs, otherwise inadequate photos will distort the reference image and result in an incorrect diagnosis and planning. Despite these drawbacks of DSD, virtual technology is evolving and it is unstoppable phenomenon which continue to improve and will surely push the dental standards even higher.

Steps: The anatomical data of the patient’s jaws is either obtained by: inserting an intra-oral optical scanner to directly capture the data or by scanning digitally the patient’s cast using a laboratory optical scanner. In both ways, data collected is then transferred to software for designing dental restoration. By the aid of the software, the intra-oral scanned data can be added with the patient’s 3D-facial images; to produce “ Virtual Patient Model (VPM)”. Also, virtual articulators have also been developed in (CAD/CAM); to simulate jaw movements.

Once the VPM have been produced, face is analyzed after placing the reference lines in relation to the smile. Then, the frameworks of smile “ lips” are outlined in the software. Smile analysis relies on certain references as: incisal edge position, midline symmetry, gingival margins and contour. Eventually, teeth that will be restored are designed based on the size, shape and color. Also teeth alignment and inclination are adjusted to eliminate the dark corridors and to get an adequate embrasure space, contact points and areas. Finally, teeth color and translucency are established to finalize the smile.

Once the digital proposed plan has been approved by the clinician and the patient, mock-ups are immediately milled and tried in. Patient can evaluate the new design function and esthetic to inform his/her dentist of any modifications needed. Changes are done if required or if not then mock-ups are scanned and definitive restorations will be fabricated in very short time with great accuracy.

Comprehensive esthetic treatment requires careful assessment, planning, and multi-disciplinary approach. Therefore, when planning to change a patient’s smile, diagnostic wax-up and mock-up are the most important tools. As have been noted, the various benefits of mock-up when designing a smile includes: easy way of communication between the patient – dentist - lab technician, aid in fabrication of provisional restorations, allows the patient and dentist to evaluate the new smile design from more than one perspective and it saves money and time by avoiding the multiple repetition of the final restorations. These diagnostic mock-ups can be produced in three ways: free hand direct mock-up in composite, mock-up according to the wax-up and CAD/CAM. Each method has it’s own laboratory steps, materials, advantages and disadvantages, in which technique selection depend on the availability of modern equipment in the clinic as well the case difficulty. When planning a procedure we should look forward to achieve the greatest standard of care to the patient, aim to dramatically reduce the operator’s errors, since at the end the success of treatment relies on the patient’s satisfaction.