Although composites are permanent restorative materials, a composite restoration usually lasts for about 5-8 years depending upon size of cavity and location of the tooth in which filling is placed. But if the restoration is discolored or chipped of it can be repaired easily without the need of removing complete restoration
A benefit of composite restoration is that it can be repaired easily if a small part of it is chipped off or discolored. There is no need to remove the whole restoration if a part of it becomes defected. Only that part of the restoration that has become defected is reduced and re-build with new material. But if the defect is large, filling has to be replaced and whether to replace the filling or repair the defected part solely depends on the decision of dentist.
Discoloration: Composite dental fillings stain and discolor over a period of time. There are more chances of early discoloration of the restoration in people who consume more tea, coffee, soft drinks and smoke or chew tobacco. Sometimes discoloration appears when the patient gets teeth bleached after the placement of composite restoration. In such a case colour of teeth whitens but that of composite does not change. So, the restoration has to be repaired or replaced depending upon the extent of discoloration.
Decay of Tooth: If patient does not maintain good oral hygiene accumulation of plaque and food debris around the restoration may cause the tooth to decay again. Sometimes bonding of the composite with the tooth may fail and plaque accumulation in the space created leads to decay of the tooth.
Chipping Off: A part of restoration may get chipped off while biting in a very hard object or due to trauma. There are more chances of fracture of filling if composite filling is present in tooth which is subjected to high forces of mastication and people having bruxism (people who clench/grind their teeth).
Lack Of Durability: Composite fillings are not as long lasting as the amalgam fillings. They have a life span of 2-10 years on an average. They wear rather easily when placed in back tooth.
High Cost: Composite dental fillings may cost more than amalgam fillings as they involve a more sophisticated procedure and more expensive materials
Increased Chair Time: Composite dental fillings process take extra 20 minutes when compared to amalgam dental fillings. Because the composite material needs to be applied, whereas the amalgams are just placed.
Additional Visits: If composite fillings are used for inlays or onlays,then more than one visit to the dental office is required.
Shrinkage: It is another common problem with composite fillings, especially during light curing. Shrinkage during polymerization leads to poor marginal seal, marginal staining and recurrent caries. Shrinkage can be reduced by placing the filling in thin layers.
Hence, composites are definitely not a fool-proof, permanent method of tooth restorations. As always, proper diet, good oral hygiene and regular dental visits are the keys to extend the life of composite fillings.
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