All about dental composite

Dental composite fillings are white fillings made of glass ionomer cement. This material has long been used as a buffer between the composite and the dental pulp because of the toxicity of the composite. As technology has advanced, composites have become less and less toxic to the tooth and the use of this cement has been reduced to temporary dressings or fillings on temporary teeth.

How many types of dental composite are there?

There are several types of dental composite. One of the classification criteria is particle size. In general, a dental composite will have macro, micro, nano or hybrid particles. Macro particles have a higher strength but a slightly more matte appearance and are used for fillings in the lateral area, while micro and nano particles can be polished better, have a more natural appearance and lower strength than macro particles. These are used especially on the front teeth together with the hybrid ones which represent a balance between aesthetics and resistance.

How long do dental composite fillings last?

This is an unanswerable question because the causes of composite material degradation are multiple. As a rule, the most important factors are the size of the filling and its localization on the tooth but not only. The larger a dental filling is and the more it is located in an area of maximum impact during mastication, the less likely it is to last for many years. Other factors that lead to the degradation of fillings are:

• • Saliva. The main component of saliva is water. The fillers begin to dissolve in saliva or water and in this way harmful substances are released into the body.
  • Chewing forces. Repeatedly subjecting dental composite resin fillings to normal chewing forces leads to progressive degradation and crack growth, which ultimately leads to failure of these materials.
  • Thermal modifications. Routine eating and drinking can induce intraoral temperature changes. These temperature changes produce an antagonistic environment for the materials as they have a different coefficient of thermal expansion compared to natural teeth. The thermal fluctuations encountered in vivo can induce surface stresses due to large thermal gradients near the surface which, in turn, can lead to degradation of these materials.
  • Oral microbes. Now here is a very important piece of information: an in vitro study showed that bacteria colonized faster on composite resin fillings which led to a pronounced degradation of the surface of the filling. In practice, this type of material favored the development of dental caries.
  • Composite application. Any dental composite material has a shrinkage index. This means that after being hardened with a lamp it shrinks to some extent. The dentist can largely combat this factor by the technique of layering the composite.

How toxic are these compounds to health?

Most dental composite materials are composed of methacrylate resin monomers of various sizes and molecular weights. The common dental composite materials used for caries filling are composed of conventional methacrylate monomers, which are BPA, Bis-GMA, TEGDMA, GlyDMA and HEMA. These are harmful substances that, over time, are eliminated from the filling in our body. Just a reminder, these substances are also present in the white-colored fillings, similar to the regular tooth fillings used today. What matters is the degree of toxicity that the various substances have for the body through absorption. These toxic substances are absorbed into the body through the oral mucosa, dental pulp, saliva and ingestion.

The toxic materials from which a dental composite can be made can harm:

• dental pulp;
• favor the appearance of bacteria that cause cavities;
• natural tooth repair processes;
• gum cells;
• collagen production;
• odontoblast mineralization.

What choice do we have?

A non-toxic dental composite has material that does not contain BPA, Bis-GMA, TEGDMA, GlyDMA and HEMA and has a much lower shrinkage index than conventional composites. These composites are also suitable for lateral and frontal areas due to their hybrid composition. Due to their low shrinkage index and the fact that they do not favor the growth of bacterial colonies, these materials last longer.

To benefit from the advantages of these state-of-the-art dental composites, we invite you to make an appointment in any of our Life Dental Spa clinics.