Composite veneers are a good option for aesthetic rehabilitation, although all dentists should always approach this kind of restoration with minimal preparation. Reliability and durability of dental procedures is important to all of our patients, especially to the younger ones whose teeth still have a very long way to go. To this end, the more conservative a clinician’s approach is, the safer his/her treatment options are being played; the advantage is, of course, not only for the clinician, but it means that out patient’s teeth have undergone minimal treatment and have lower risk and many more solutions for any problem that might come in the future.
Unfortunately, today, a trend to obtain aesthetics still relies much on subtractive techniques (heavy preparations on sound tissue). For this purpose, a perfect approach is to work additively, this way we minimizing tooth preparation and enhancing the aesthetic outcome, but always through accurate planning.

Fig.1
A 17 year old girl came to the clinic complaining about the aspect of her central incisors. She told us she had broken both of her centrals back when she was a kid. Tooth 11 became necrotic two years ago and was endodontically treated.

Fig.2
After opening of the pulp chamber of 11 a iatrogenic vestibular perforation was also found. We decided to go for endodontic retreatment of the tooth and surgery to restore the periodontium. Because of the very young age of the patient, the restoration protocol that we chose included post restoration and additive veneers.

Fig.3
The teeth were pre restored, to be able to follow the rest of the therapy under a more comfortable environment for both clinician and patient.

Fig.4
Crown lengthening was chosen to get a harmonious geometry of the smile. Tooth 21 was also internally bleached with a hybrid walking bleach/in house technique. Once the endodontic therapy was finished, the guttapercha was sealed with a layer of flowable composite at the cervical level. Home trays were delivered to the patient so the bleaching agent can be changed everyday inside and outside of the tooth. Once the bleaching is completed, the access is definitely closed either with composite or a non-prep adhesive fiber post (only removing guttapercha form the canal)

Fig.5
A wax-up was made to provide the clinician and the patient with an idea and a guide to the final aspect of the restorations.

Fig.6
One of the most significant images is the occlusal aspect, which will determine how much and how thick our final restorations will be.

Fig.7
Transparent silicone key which will be useful for mock-up, preparation and temporaries.

Fig.8
Flowable composite was injected into the silicone key in order to create the mock-up

Fig.9
The key was fit on the teeth and the composite polymerized through the transparent silicone.

Fig.10
Mock-up for aesthetic evaluation and eventually, the same mock-up can be used for the preparation stage.

Fig.11
Preparation was carried out through the mock-up in order get the most conservative preparation. Note that 90% of the space created is performed in composite, so the natural enamel touching is minimal. In the picture, incisal reduction (1.5mm)

Fig.12
Aspect after incisal reduction

Fig.13
Preparation through the mock-up allows perfect control of the thickness of the preparation.

Fig.14
Preparation guides

Fig.15
Flattening of the preparation

Fig.16
Prepared mock up to be removed, followed by finishing of the tooth prepared surface.

Fig.17
Finishing of the preparation

Fig.18
A retraction cord was put into the sulcus before impression.

Fig.19
Before tray insertion the impression material was put on top of the sulcus in order to ensure the precise impression of the preparation limits.

Fig.20
Final result.

Fig.21
1 year control shows perfect integration at the merging of hard and soft tissues.

Fig.22
2 year control shows a good tissue healing and color integration. And the veneers which were made of composite indirectly, have almost the exact same surface as in time zero. Further control appointments will be made.
Conclusions
The most conservative approach often provides us with the best solution when treating our younger patients. Together with being conservative, using a predictable protocol that includes precise built-in guides, as the through-the-mokup preparation does, makes it feasible and repeatable thus ensuring the best results on each of our patients.
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