A Full Mouth Reconstruction.
Tetracycline has been on the market for more than 60 years and is used in the treatment of many gram-negative and gram-positive bacterial infections. If used for children under the age of eight years old, it causes permanent staining of the teeth.
Tooth staining/discoloration with tetracycline is influenced by the dosage used, length of treatment or exposure to the antibiotic, stage of tooth mineralization (or calcification), and degree of activity of the mineralization process. The discoloration is permanent and can vary from yellow to gray or brown.
A 48-year-old male patient with tetracycline staining visited my office with a chief complaint of failing veneer restorations that were placed eight years ago. The patient had veneers placed over the maxillary anterior eight teeth to cover the unsightly appearance. The tetracycline staining was severe throughout the patient’s entire dentition, which can be a challenge for treatment, from an aesthetic perspective.
The patient has professional responsibilities that require him to be in front of people, so his smile is critical to his self-esteem and professional success.
The Exam and Workup
After x-rays and an intraoral examination, the patient showed gum recession, chipping and breaking of the old veneers, and incisal edges that were fracturing and breaking (see Figure 4).
To determine viable treatment options, I performed an occlusal diagnostic review. The patient showed a healthy vertical dimension, with a Shimbashi measurement of 18 mm. The patient did not complain of headaches, joint pain, jaw popping, or sleep apnea symptoms, so he was asymptomatic with regard to such issues.
After utilizing a T-Scan® bite analyzer (for occlusal force and timing), I found that the patient was hitting extremely hard on his front anterior eight teeth. The T-Scan® confirmed that his initial occlusal contacts were distributed heavily in front, before the posterior teeth made contact.
I diagnosed the patient with anterior entrapment, which was causing his front teeth to wear down and explained the chipping, breaking, and recession on the anterior teeth. A simple palpation on the labial surface of his front teeth would elicit fremitus.
Because the patient’s jaw joint tested asymptomatic, he was a straightforward full mouth rehabilitation case. Proper full mouth impressions that captured his full oral anatomy (hamular notches and incisal papilla) were taken.
As seen in the initial retracted photo (see Figure 5), his anterior occlusion could be considered end-to-end. I ordered a full workup to adjust the anterior occlusion of his upper eight and lower eight teeth, and to replace the missing molar.
I decided to create long centric in the anterior—taking the pressure off the anterior teeth by creating freeway in an anterior-posterior slide. To check for this, ask your patient to bite on their back teeth. Ask if the patient can slide the lower teeth a bit forward before bumping into the anteriors. If so, the patient has “freedom in centric occlusion” (also known as long centric). Remember, centric occlusion is another term for intercuspal position (ICP).
Photography of the patient showed three points of correction for the maxillary canting: 1. Establishing a new pitch (the AP direction of the maxillae and the anterior teeth), 2. A new shift or de-canting of the occlusal plane (the roll), and 3. The yaw, a shift of the entire upper maxillary plate from left to right. I requested that these issues be accounted for in the wax-up from the lab.
The patient and I discussed the new width and length of the central incisors. A full mouth periodontal screening (probing) of the dentition was performed so that if I needed to do tissue corrections, I would know how much tissue we could remove. Information was communicated to the lab about the new gingival height and zenith of the front anterior six teeth, along with a new tissue-corrected Shimbashi.
After assessing the patient’s features, I always determine if a patient is brachiocephalic, mesocephalic, or dolichocephalic so I can communicate whether or not the occlusal anatomy should be flat or animated for the wax-up. The patient was determined to be brachiocephalic, so I requested flat anatomy from the lab for the wax-up.
Also, in the occlusal design, I wanted to create a cuspid protected occlusion, which is a cuspid rise and protrusive rise. In every full arch or full mouth case, I want to create a cuspid-protected occlusion in the wax-up. If there are any diastemas to close, that is also mentioned. This particular patient had diastemas in the posterior of his mouth.
The patient was presented with the treatment strategy that included creating a new dentition that would allow him to move outside the constraints of his worn dentition and would preserve his teeth for a lifetime. After the case presentation, which included showing the patient the wax-up (which the patient paid for), the patient accepted treatment and was ready to proceed.
The Procedure
Dentists are sometimes hesitant to prep full arches because they typically do not have a structured plan. Preparation of the dentition is extremely important, particularly in recording and maintaining the bite registration. The bite registration jig (provided by the lab) is a very important lab communication tool for maintaining or changing the vertical dimension (see Figure 7).
A prepping sequence is vital to keeping what I refer to as the vertical stops. For example, if all 14 upper teeth are present, the first sequence is to prep teeth numbers 3 to 6, followed by teeth numbers 11 to 14.
At this point in the procedure, I take a sitting up bite registration with the bite jig. The bite jig matrix creates repeatable centric occlusal positioning when relined. The tripod of centric stops are the most distal teeth bilaterally and the anterior incisors. These teeth should be prepped after the bite jig has been relined, showing prepped teeth numbers 3 to 6, and 11 to 14 as new vertical stops (see preparation checklist).
Anterior Prepping Correction
In prepping the anterior six teeth (numbers 6 to 11), I utilized the Brasseler 5856 diamond. It is a different pitch of the diamond to flare the anterior maxillary when prepping, which typically is more of a reduction on the lingual surface.
Having to remove the older veneers, I changed the axial inclinations and created a better anterior overjet instead of an end-to-end anterior bite (see Figure 1, for the anterior prep and the noticeable striations of the tetracycline intrinsic stain).
For materials to mask the tetracycline stains, I decided on the IPS e.max restorations for teeth numbers 5 to 12, a 3-unit PFM bridge, and full coverage metal crowns on the posterior second molars.
Seating the Restorations
The sequence for cementing a full arch after try-in of all restorations went as follows:
1. Cementation of posterior molars. Started with right side, cementing molars with Multilink® Automix from Ivoclar. Allowed for proper curing time before placing rubber
dam clamps.
2. Placed rubber dam and sealed off palate.
3. Cleansed teeth with Consepsis®, rinsed, and lightly dried.
4. Acid etched teeth, rinsed, and lightly dried.
5. Applied Telio CS desensitizer from Ivoclar, lightly dried.
6. Applied adhesive to tooth structure, multiple coats.
7. Applied Variolink® Esthetic light shade veneer cement to restorations.
8. Placed restorations shy of fully seating.
9. Fully seated one restoration at a time, and spot tack cured at the gingival margin for three seconds then continued to next tooth, tack cured and so on. Once all restorations were tack cured, I gently wiped away excess cement from the lingual surface with a cotton roll, starting incisally towards the gingival margin.
10. Visually checked the lingual margin to assess full seating of restorations.
11. Wave cured over all restorations for two seconds. Gently removed excess cement. Applied DeOx® from Ultradent at the margins. Fully light cured for 20 seconds (oxygen inhibitor).
12. Removed all cement and flossed interproximally.
13. Finalized occlusion after 48 hours using a Tekscan® for time and force (see Figures 8, 9, and 10).
Quality Materials
A literature review (five external studies and one internal Ivoclar study) of longevity and clinical performance of IPS e.max restorations revealed favorable clinical results. IPS e.max Press are biocompatible lithium disilicate glass-ceramic ingots. They offer the fit, form, and function which is expected from pressed ceramics. In addition, they offer flexural strength of 470 MPa and resilient fracture toughness.
With optimized aesthetic properties, creating all-ceramics restorations that offer true-to-nature results has never been so easy. In the literature review, pressed ceramic e.max and CAD e.max were compared. Clinical recall at 28 months after luting with a light polymerized resin cement showed a 97 percent survival rate for the e.max CAD and 98 percent for e.max Press. The clinical accuracy of the marginal fit for both e.max CAD and e.max Press are excellent.
Lithium disilicate is becoming the restorative material of choice for single-unit indirect restorations, with a range of strength of 360–500 MPa. This is a dental aesthetic material that I have been waiting for! It offers maximum strength, superior esthetics, higher-edge strength (finishing thinner), and ease of luting to teeth.
Overall, e.max is a trusted material when masking color or stains is a top priority! And in today’s dental environment, patients are the most important priority.
Results
The patient was elated with the results of his new smile. Since completion of the case, his confidence level has reportedly increased dramatically. People have responded by saying, “Wow you look great! You look vibrant!” The results are subtle enough that the restorations look natural, yet it is a dramatic and noticeable improvement in function and aesthetics.
