Composite veneers simply refer to synthetic resins used as restorative adhesives or material in dentistry. Synthetic resins are mostly preferred due to being insoluble, easy to manipulate, insensitive to dehydration, reasonably inexpensive and aesthetic. They are commonly composed of Bis-GMA analog or Bis-GMA monomers, a filler component such as photoinitiator and silica. To achieve a specific desired physical properties e.g. flowability, dimethacrylates are usually added; however, further modification of physical properties can be achieved through formulation of unique levels of each component. Use of composite restoration with enamel and dentin bonding procedures helps in restoring back the tooth its original/former physical integrity unlike use of amalgam which involves filling of the hole and needs retention feature for the purpose of holding the filling.
HISTORY OF USE
At first, composite veneers used to be very prone to breakage and leakage because of the weak compressive strength; however, they were greatly improved between the year 1990s to 2000s hence having sufficient compression strength for being used in posterior teeth. The current composite veneers are meant to have low thermal shrinkage coefficients and low polymerization hence allowing them to placed in large quantities while at the same time ensuring good adaptation walls of the teeth cavity. The procedure for the placement of composite veneer requires great attention otherwise it might fail prematurely. To enable the composite to be compatible with the tooth, then dryness of the tooth must be maintained at all time during the procedure.
At first, composite veneers used to be very prone to breakage and leakage because of the weak compressive strength; however, they were greatly improved between the year 1990s to 2000s hence having sufficient compression strength for being used in posterior teeth. The current composite veneers are meant to have low thermal shrinkage coefficients and low polymerization hence allowing them to placed in large quantities while at the same time ensuring good adaptation walls of the teeth cavity. The procedure for the placement of composite veneer requires great attention otherwise it might fail prematurely. To enable the composite to be compatible with the tooth, then dryness of the tooth must be maintained at all time during the procedure.
Composite veneers are normally placed when still soft in nature, though they harden and polymerize to form solid fillings due to exposure to a certain wavelength. Lack of penetration of light beyond 2 to 3 millimeters into the composite makes it quite challenging for all composite to harden therefore, placement of thick layers of composite in the tooth makes the it to remain soft a condition that might lead to killing or irritation of the tooth's nerve. It is thereby recommended to wait until the composite has completely polymerized before addition of more layers, though too much filling is not recommended as it may lead to chewing sensitivity.
Composition of composite veneers
This type of veneers typically comprise of inorganic filler e.g. silicon oxide and resin-based oligomer matrix e.g. urethane dimethacrylates or bisphenol A-glycidlmethacrylate. Compositions differ widely, with engineered glass ceramics and filler gasses as well as proprietary combinations of resins thereby forming the matrix. The filler is meant to provide the composite with translucency and wear resistance. A coupling agent e.g. silane is used in enhancement of the bond between the two components. Application of the external energy such as heat or light makes the initiator package e.g. lucirin, camphorquinone or phenylpropanedione to start resins' polymerization reactions. A catalyst package is used to control its speed.
This type of veneers typically comprise of inorganic filler e.g. silicon oxide and resin-based oligomer matrix e.g. urethane dimethacrylates or bisphenol A-glycidlmethacrylate. Compositions differ widely, with engineered glass ceramics and filler gasses as well as proprietary combinations of resins thereby forming the matrix. The filler is meant to provide the composite with translucency and wear resistance. A coupling agent e.g. silane is used in enhancement of the bond between the two components. Application of the external energy such as heat or light makes the initiator package e.g. lucirin, camphorquinone or phenylpropanedione to start resins' polymerization reactions. A catalyst package is used to control its speed.
Advantages of composite veneers
There are numerous benefits associated with compositeveneers, however, the main benefit of composite veneers is improved aesthetics as compared to other traditional teeth filling. Other benefits include; strengthening of the structure of the tooth due to being glued into the tooth, existing in wide range of colors hence making it difficult to be noticed, the invention of acid etching of tooth or teeth to enable a tooth micromechanical bond enhances optimal adhesion of tooth restoration hence avoiding creation of retention features that might destroy healthy tooth.
There are numerous benefits associated with compositeveneers, however, the main benefit of composite veneers is improved aesthetics as compared to other traditional teeth filling. Other benefits include; strengthening of the structure of the tooth due to being glued into the tooth, existing in wide range of colors hence making it difficult to be noticed, the invention of acid etching of tooth or teeth to enable a tooth micromechanical bond enhances optimal adhesion of tooth restoration hence avoiding creation of retention features that might destroy healthy tooth.
Direct dental composite veneers
These are composites usually placed in a clinical approach, whereby polymerization is achieved through a hand held curing heat/light that produce a certain wavelengths aimed to the catalyst and the initiator packages involved. When using this method, it is advisable to put a shield the operator's eyes and the light tip while holding the curing light near the surface of the resin as possible. This technique can be used for filling gaps, minor teeth reshaping and partial crowns found on a tooth.
These are composites usually placed in a clinical approach, whereby polymerization is achieved through a hand held curing heat/light that produce a certain wavelengths aimed to the catalyst and the initiator packages involved. When using this method, it is advisable to put a shield the operator's eyes and the light tip while holding the curing light near the surface of the resin as possible. This technique can be used for filling gaps, minor teeth reshaping and partial crowns found on a tooth.
Indirect composite veneers
These types of composites are usually cured outside the patient's mouth via a processing unit capable for producing high energy levels and intensities than that of handheld light cans. These composites are meant for: reshaping of the teeth, filling cavities contained in the teeth, partial or full crowns on the tooth and filling teeth gaps usually called diastemas via use of veneers that have a shell-like shape.
These types of composites are usually cured outside the patient's mouth via a processing unit capable for producing high energy levels and intensities than that of handheld light cans. These composites are meant for: reshaping of the teeth, filling cavities contained in the teeth, partial or full crowns on the tooth and filling teeth gaps usually called diastemas via use of veneers that have a shell-like shape.
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