The additive aesthetic mock-up
Creating beautiful smiles for appreciative patients is perhaps the most rewarding experience one can have as a dentist. Helping people who have been self-conscious and nervous about showing their teeth, or who have lost effective function, become confident and comfortable is not only satisfying but also fun.
I used to believe that if I just told people what they would look like, they would jump at the opportunity to have me spin down their teeth and place my beautiful crowns and veneers. When that didn’t work so well, I heard that I needed to have my mounted diagnostic models ready.
Two articulators, one with the original untouched diagnostic casts and the other with the beautifully waxed prototypes, would allow the patient to see how nice their teeth could look and, of course, how hard I’d worked at making it look pretty! That approach met with a greater degree of success but I still had trouble helping people move forward with treatment.
There are two reasons those techniques didn’t work. One is that I had not learned how to listen carefully to my patients so that they might choose health for themselves. The other is that they simply couldn’t see what they might look like. Full understanding of this simple idea came when a colleague sought me out to help with her dentistry.
The case report
Lee’s chief complaint was sore muscles, an ineffective bite splint, and a history of clenching and bruxing. She also mentioned that once these issues were cleared up she might be interested in improving the aesthetics of her smile. Data was gathered during a comprehensive clinical exam including articulated diagnostic casts, a CT scan using 3D cone-beam technology, clinical photographs as well as a complete head, neck and dental examination.
Since the chief complaint was muscle tenderness and an ineffective bite splint, the initial phase of therapy was fabricating a new bite appliance for her lower arch. She wore the appliance 24/7 with periodic adjustments until the muscle symptoms subsided and her bite became comfortable on the appliance. At that time a centric relation record was made and the diagnostic casts were remounted.
Lee was ready to think about a definitive diagnosis and treatment plan after her chief complaint was addressed to her satisfaction. In fact, had that not occurred she would not have moved forward with further treatment. During appliance therapy it became clear to her that the length of her maxillary centrals was slightly deficient, she had interferences to the crossover position, and was very dissatisfied with the appearance of her upper front teeth, especially the short right central and the black triangles.
There were structural and occlusal issues with her posterior teeth which also surfaced and she wished those to be addressed as well. The final restorative treatment plan included bonded porcelain restorations from maxillary first molar to first molar as well as bonded porcelain posterior restorations on the lower premolars and first molars, and cast gold on all four second molars. The case would be treated to centric relation.
Lee’s mouth was equilibrated and new casts were made and articulated so that the final workup could be accomplished. At this point the ceramic artist, Matt Roberts, was consulted on the case and after preliminary discussion with him about the objectives of treatment, a decision was made to do some preliminary waxing to show to Lee. The goals were to bring the incisal edges labial about .5mm and to lengthen the centrals about 1mm.
The wax-up was returned and with great excitement presented to Lee for her approval. Here is the learning moment; Lee is a dentist and we both assumed that she would be delighted with Mr Roberts’ initial wax-up, because it was beautiful. However, when she looked at it we were also both surprised at how little impact it had for her. Lee couldn’t see how this would fit in her mouth.
Lee’s aesthetic changes were all additive in nature. Mr Roberts changed line angles and contours so that the silhouette of the teeth was more pleasing, and he added length to give her more length when her lips are at rest. When changes are additive in nature it is very easy to provide the patient with an aesthetic preview or mock-up that allows her to visualise the proposed changes in her mouth.
A putty matrix was fabricated over the wax-up using a silicone lab putty. The matrix is trimmed to the gingival margins of the anterior teeth. The matrix is tried in the mouth to ensure close adaptation to the teeth. A bisacryl provisional material is used to create the mock-up. In this case 3M Pro-temp III Garant was syringed into the incisal 1/3 of the putty matrix. The matrix was placed and then stabilised for two minutes.
The matrix is then gently removed and a 12B scalpel blade is used to trim the flash. The patient is asked to move the jaw through all excursions to check functional parameters. If the mock-up looks acceptable it is shown to the patient. The patient is allowed to speak and move the lips over the teeth and to simulate chewing motions. If those parameters seem acceptable the bisacryl is then removed from the teeth.
Using 35% phosphoric acid, the incisal edges of the teeth are spot etched. Enamel bonding agent is applied to the incisal edges and the process of placing the bisacryl over the teeth with the putty matrix is repeated. The mock-up is trimmed again and the occlusal parameters are checked again. The envelope of function is carefully checked by simulated chewing motion and appropriate adjustments are made.
Phonetics are checked and tooth length against the wet-dry line of the lower lip is evaluated. Once these parameters are in harmony, the patient is allowed to wear the
mock-up home for 24 hours with the understanding that it will probably break with chewing or eating.
The patient returns the next day and the mock-up is checked. Any slight adjustments are made if needed and the patient is asked for approval. With approval an impression of the intact mock-up is made and mounted against the existing lower equilibrated model. Photographs of the mock-up are made in the maximum intercuspal position and in excursive movements. The new models and photographs are then sent to the lab for the final wax-up.
This technique will only work if the changes are additive in nature. It is much harder to create an aesthetic preview if reductive alterations dominate the new anterior arrangement.
Back to the patient
The gift of the mock-up was Lee’s ability to wear it home and live with it overnight. She was able to show her family, test the phonetics for an extended period and to see herself in the comfort of her home. When she returned the next day she was enthusiastic about the new look. She had also discovered that the incisal edges were slightly palatal. We made minor corrections and the new impression was made. Mr Roberts utilised the new impression as a guide to complete the final wax-up, which becomes the template to produce the provisional or prototype of the final restorations.
Patients who are interested in comprehensive care are making significant decisions about their health. Part of the job of the restorative dentist is to create experiences so that the patient can both understand their present condition and see a future vision for themselves. The more we are able to minimise surprises or uncertainty for those who seek our services, the more likely we are to succeed.
As dentists we often forget the complexity of our own learning. We forget how long it took us to understand this complex stomatognathic system we are privileged to treat. If it takes us so long to fully understand the human mouth it really is no surprise that our patients have trouble immediately grasping what we suggest as treatment. We can shorten the distance to success by understanding how adults learn and recognising that most patients need more than just an explanation to reach understanding and then move to action.
The additive mock-up not only serves us as a diagnostic tool, it is a great instrument of learning for our patients.
Dr Steve Ratcliff is chairman of the Department of Education at The Pankey Institute for Advanced Dental Education in Key Biscayne, Florida, USA, where he also maintains a position in the faculty practice. He lectures extensively on the topic of comprehensive care and developing a relationship-based practice.
Dr Steve Ratcliff will be presenting, along with Dr Lee Ann Brady and Dr Gary DeWood, The Pankey Institute’s Function to aesthetics – essentials to a brilliant practice in London in September. For more information, or to book your place, call 0800 371 652, email [email protected] or visit www.independentseminars.com.