Where the composites can be used
Composites are the tooth colored material which can easily bond to the tooth surface. There are different shades available so it can match easily with the color of the tooth and gives very esthetic looks. It has all the properties of the good filling material like strength, wear resistance, insolubility in the oral fluid and so on. So the composites can be used almost every where. The few situations where the composites are indicated are-
All types of cavities can be filled with composite filling material especially if they are in the front teeth. For back teeth posterior composites are available which have better strength. If the gaps are present between the front teeth, it can be closed by using composites. Composites can also be used for core built up for the teeth which are fractured to the extent that post and core is indicated. It can be used for splinting the teeth when they become mobile due to trauma or after some periodotal problem. Composites are also used for giving the veneers. They can be used as preventive treatment as pit and fissure sealant.
Where the use of composite is contraindicated?
Initially composites are not used in the back teeth as the back teeth have to chew the food. Forces are more on those teeth which causes more wear of the tooth and the filling material. Composites whch are used for front teeth do not have that much wear resistance and the chances of filling failure like fracture of the filling was more. But now with the invent of posterior composites, which have very high wear resistance that problem is solved.
So the only contraindication for composite is the areas or situations where isolation is a problem like in children. If the child is very small , isolating the area is a problem. If the area is not isolated properly and the saliva contamination is there, the the filling failure will be there. So in such situations composite fillings are not recommended.
What is the procedure for using the composites ?
The first step is to prepare the tooth. After the tooth is prepared the shade of the composite is selected. Shade selection is an important step mainly for the front teeth. During shade selection following things should be kept in mind like:
- It should always be selected in the natural day light.
- The shade should be selected before the tooth is subjected to any air drying because air drying will make the tooth dehydrated and dehydrated tooth looks lighter as there is loss of traslucency.
- After the shade selection the tooth is isolated using the rubber dam.
Acid Etching- after the shade is selected the next step is to etch the tooth. Etching is done to increase the bond strength between the tooth and the filling material. Etching is done with 37% phosohoric acid which is available in the gel form or the liquid form. It is applied on the tooth surface for 20 to 30 seconds according to the manufacturers instructions. It is washed for 5 seconds and then air dried.after etching the tooth should have frosted glass like apearence.
Application of Bonding Agent –after etching the tooth surface the bonding agent is aplied with the applicator.the area is then light cured for 10 sec. if the saliva contamination occurs then the area has to be etched again for 10 sec and then bondig agent is again applied.
Applying the Composite – after applying the bondig agent the selected shade of the composite material is applied and is light cured. If the filling is big then the composite is applied in the increments of 1-2mm and each increment is cured before applying the next.
Finishing and Polishing –after applying the composite and curing it properly the proper fiishng of the restoration is done. It is checked for any high points and the excess is removed. After finishing, polishing is done with the help of polishing burs,rubber cups and the polishing paste