Closing of the diastema with composites can immediately and dramatically change the beauty of the smile just in a single appointment. It may also help to improve speech and food particles being caught in the space between the teeth.
The ratio between length and width of incisors teeth is about 10:8, so first step would be to measure the dimensions of the incisors where diastema is to be eradicated.
If the space between incisors (diastema) is less than 3 mm it can be categorized as “simple diastema”. If, however, the space is more than 3 mm then the problem of shine through the two incisors would be too big to look natural, hence the condition shall be tackled by “complex diastema “ closure technique.
Complex diastema closure: If the gap is more than 3 mm, then the diastema is closed as in simple diastema closure but to compensate the increased width of the tooth opposite side; the tooth is also reduced to maintain the basic length- width ratio of 10:8. Now the so created diastema on distal side of the tooth can be closed by simple diastema closure technique on the mesial side of the abutment of the primarily effected tooth. For example, if there is diastema of more than 3 mm between two central incisors the reduction of increased width of central incisor is compensated by reduction on its distal side till the ratio of 10:8 is maintained.
Now diastema so created between central and lateral incisors can be filled by adding composite on the mesial side of the lateral incisor. This complex diastema closure technique may have to be combined with full facial veneer sometimes.
STEPS IN CLOSURE OF DIASTEMA
2. Select the shades
3. Preparation of the tooth: For simple closure no preparation is required. Check the tooth for stains and remove them if present. Remove tooth material from the distal side in complex cases to main 10:8 ratio of length-width of the tooth. It should be done without local anaesthesia and without exposure of the dentine, lest it should become sensitive tooth later. Start with a single tooth first and complete the procedure up to final polishing, before starting the next tooth.
4. Etch the tooth: Etch the surface of the tooth for 15 seconds on mesial, facial and lingual/palatal side with 37 per cent phosphoric acid etchant gel, use mylar strips to avoid etching of the abutments. The restoration should cover up to one-third of facial and lingual or palatal side of the tooth.
5. Wash the etchant gel: With air/water spray for 5 to 10 seconds and blot dry the tooth.
6. Adhesive application: Apply adhesive as per protocol for 20 seconds avoiding contamination of the adjacent tooth. Light-cure for 10 seconds.
7. Filling the gap (diastema):
Simple Diastema: Inject a small amount of some microfil like hybrid from the facial side, completing the whole facial contour, check the midline before curing, light-cure for 40 seconds. Next inject second incremental layers from palatal/lingual aspect, blending the material evenly into labial/lingual sides with proper attention to restore the tooth anatomy on diastema side. Complete contouring, curing, finishing and polishing of this restoration before starting the job on the next affected (abutment) tooth.
Repeat the steps on the next needy prepared tooth with or without using a mylar strip as composite does not stick to highly polished surface and so shall not bond to it.
For the above procedure sometimes we need immediate separation of the teeth to restore the correct mesial slope anatomy. Separation can be done with the help of a plastic instrument or a carver (Lacron’s) held in the gingival embrasure between the incisors, give a twist torque force till a popping sound is heard which indicates that the teeth are seprated.
Complex Diastema: Complex diastema closure needs use of hybrid opaque composite to prevent shine through followed by use of a translucent microfil. If recent compounds like Esthet- XTM is used there is no need of a microfiller as this material comes in 31 shades selection pack. Other options of materials are: Point - 4TM (Kerr) RenewTM (Bisco) and vitalescene (Ultradent).
SUMMARY
To close a diastema decide wheather it is of simple or complex variety by measuring length and breadth of the tooth, ideal ratio is 10:8 length/breadth. More than 3 mm wide diastema is categorized as complex variety.
In complex variety preparation, reduce opposite side of the diastema side of the tooth maintaining its anatomy and length breadth ratio, reducing only in enamel. Do not expose dentine and use no local anaesthesia.
Steps
2. Select shade.
3. Prepare the tooth remove stains, etc.
4. Etch the tooth on mesial/facial and lingual aspect beyond area of bonding after separating abutments with mylar strip.
5. Wash etchant gel from the tooth surface after 15 to 20 seconds with air-water spray for 1 to 2 seconds and blot dry, leaving some moisture for hydrophilic adhesive material to penetrate deep into hybrid area.
6. Apply adhesive material taking care not to contami- nate abutment. Leave the adhesive undisturbed for 20 seconds.
7. Air blast (by air syringe) the excess solvent of adhesive material for 5 seconds. (Air thinning).
8. Light-cure for 10/20 seconds.
9. Check for glossy surface, “matt” free surface should be achieved. If “matt” surface is still present repeat the adhesive application and cure again till they also become glossy.
10. Apply microfilled composite material to build the required shape of tooth paying special attention to the midline, sculpt facial side first.
11. Light-cure each increment for 40 seconds.
12. Apply material on lingual/palatal side of the tooth and sculpt the anatomy specially on the mesial side and then light-cure for 40 seconds.
13. Add layers till perfect anatomy of the tooth is achieved.
14. Finish and polish as per protocol.
15. Repeat the same steps on the next tooth in complex diastema closure using or not using mylar strips. Note: In complex diastema closure use opaque layer first followed by translucent layer of composite material. But with recent microfilled materials it may not be necessary
Để truy cập toàn bộ bài viết, xin vui lòng xem thêm tại đây