Page 28 - WOM SUMMER 18-19

DURABILITY OF A LOW SHRINKAGE

TEGDMA/HEMA-FREE RESIN

COMPOSITE SYSTEM IN CLASS II

RESTORATIONS.

marketed during the last years 10–12 . high hydrophilicity and detergent HEMA in adhesives may lead to
DESPITE THE INCREASING USE OF RESIN COMPOSITES, Biocompatibility of dental materials activity in liposomes. It can penetrate phase separation between water
is an important consideration for all biologicalcompartments, the and the adhesive monomers 27–29 . It
THERE ARE STILL SEVERAL REMAINING PROBLEMS TO BE SOLVED. the patient and clinician. Many in extracellular and intracellular space, has been shown that HEMAinhibited
intracellular tyrosine phosphorylation
including cell nuclei and membranes.
vitro studies have shown that the
polymerization reaction, producing The monomer showed chemical– 20] , induced cell growth inhibition and
the cross-linked polymer matrix from biological interactions with many cycle perturbation and is a potent
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the dimethacrylate resinmonomers, is cell structures or processes like inducer of apoptotic cell death .
never complete. It has been reported inhibition of cell growth and decrease Cell mutation has been observed
that of the methacrylate groups, of the intracellular glutathione level after exposure to both TEGDMA
he objective of this estimated. Results. Three molar teeth cross-linking of the polymer chains. 25%–60% may remain unreacted and 18,19,21,22 . The quantity of TEGDMA and HEMA 32,33 as well as increased
randomized controlled showed mild post-operative sensitivity The free curing contraction for about 10% of the available groups leaching from restorative materials intracellular concentrations of
Tprospective trial was to during 3 weeks for temperature resin composites varies from1.0% are free to diffuse out in the oral is predominantly dependent on the reactive oxygen species (ROS) 22,34 .
evaluate the durability of a low changes and occlusal forces. After 6 to 5.0% . In the pre-gel phase, the cavity 13,14 . Adverse reactions may monomer–polymer conversion. But Exposure to low con-centrations of
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shrinkage and TEGDMA/HEMA-free years, 134 Class II restorations were material is able to flow and stresses be expected in sensitive operators in addition, chemical processus the monomers for a prolonged time
resin composite system in posterior evaluated.Twenty-one restorations, are relieved. Post-gel polymerization or patients due to the release of like erosion, enzymatical hydrolytic reduced the rate of cell proliferation
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restorations in a 6-year follow up. 8 cmf-els (11.4%) and 13 ASE-els results in stresses in the material non-polymerized monomers. Clinical disintegration and alcoholysis as possibly as result of DNA damage .
Methods. 139 Class II restorations (20%) failed during the 6 years (p and tooth structures and their studies have shown that dental resin well as physical processes like wear In addition it has been observed that
were placed in 67 patients with a < 0.0001). The annual failure rates interfaces, which may affect the composites may induce local and may also contribute to a release TEGDMA and HEMA are common
mean age of 53 years(range 29–82). were 1.9% and 3.3%, respectively. interfacial adaptation and durability systematic adverse effects, which of degradation products from the sensitizers with a high sensitizing
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Each participant received at random The main reasons for failure were of restorations 2–6 . The magnitude are caused by methacry-late (co) polymerized resin in time . Geurtsen potential 36–38 . The lower the molecular
two, as similar as possible, Class II fracture followed by recurrent caries. of shrinkage stress depends on monomers . Two frequently used and Leyhausen concluded that it weight of the monomer, the higher
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restorations. In the first cavity of each Most fractures and all caries lesions many factors like resin matrix methacrylatemonomers TEGDMA should be the aim of future studies the biophase penetration risk and
pair the TEGDMA/HEMA-free resin were found in high risk participants. formulation, amount of filler used in (Triethyleneglycol-dimethacrylate) to replace TEGDMA with more allergic potential.The risk of allergic
composite system was placed with Significance. The Class II resin the resin composite and degree of andHEMA (2-hydroxyethyl- biocompatible diluentmonomers. reactions increases due to unwary
its 3-step etch-and-rinse adhesive composite restorations performed conversion. Cuspal movement during methacrylate) eluate from different HEMA is frequently present in dental handling of the non-cured resin
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(cmf-els). In the second cavity a1- with the newTEGDMA/HEMA-free low polymerization may be perceived as resin composites, compomers, adhesives, resin-modified glass monomers . Fast penetration of
step HEMA-free self-etch adhesive shrinkage resin composite system post-operative pain 7–9 . Increasing resin modified glass ionomers and ionomers and poly-acid modified resin uncured monomers through the skin
was used (AdheSe One F). The showed good durability over six years. C-factor may result in greater stresses adhesives and have been shown composites. In adhesives, in amounts and gloves cause contact dermatitis
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restorations were evaluated using due to the larger number of bounded to be responsible for several from 30% to 55%, it reduces viscosity, in dental staff . Patients with
slightly modified USPHS criteria at INTRODUCTION surfaces. Posterior Class I and II cytotoxic reactions 16–20 . The promotes diffusion of co-monomers diagnosed allergies for HEMA and/
baseline and then yearly during 6 During curing of themonomers, a cavities will therefore show high stress diluent monomerTEGDMA show by expanding the demineralized or TEGDMA should not receive dental
years. Caries risk and parafunctional network of polymers is formed, which formation. A few low shrinkage resin biological significant properties, collagen 24–26 and enhances bond materials which can release these
habits of the participants were becomes rigid due to increasing composites have been developed and like low molecular weight, relatively strength to dentin . Omission of monomers. Recently a TEGDMA/
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