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Alternative Coinitiators Applicable to Photocurable Resin Composites

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The composite resins available on the market today are mostly light-cured resins. So, photoinitiator molecules are included in these materials which have the ability to absorb light, and as result, generate free radicals which initiate the polymerization of these resin materials.  The light curing systems most commonly employed in the composites are the camphorquinone/amine system. The photoinitiator is camphorquinone, which requires a coinitiator to perform the polymerization process. Tertiary amines (aliphatic or aromatic) do not absorb light, but interact with the activated camphorquinone to produce reactive species. However, this photoinitiator system has some disadvantages, such as the tendency to promote yellowing to resin materials low compatibility with oral tissues   and even mutagenic characteristics. PDF LINK
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Enostosis Mimicking a Supernumerary Tooth

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A 17 year old female with history of malaligned teeth was referred from orthodontist for extraction of a supernumerary tooth along with first premolars in lower jaw. This is a usual practice to gain space for future orthodontic treatment. The referral included an orthopantomogram revealing a dense, well defined radiopaque lesion in relation to the periapical region of lower left first and second premolars. It is horizontal in alignment measuring 2 cm inlength and 5 mm in width lying parallel to lower border in close proximity withroots of premolars. On examination, clinically there was no cortical bone expansion or enlargement on the labial or lingual side.  The patient did not show any signs or symptoms of infection. The orthodontist considered this radiopaque lesion (supernumerary tooth in jaw) to interfere with his orthodontic treatment or potentially cause resorption of roots.  In view of determining the proximity of this radiopacity to surrounding structures, we ...
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Best materials in the treatment of periodontitis

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Recently scientists evaluated the healing outcomes of Intermediate Restorative Material (IRM) and mineral trioxide aggregate (MTA) materials as root-end seal of teeth with apical periodontitis. They found that both the methods are effective in the treatment of periodontitis. Teeth with previous conventional endodontic root-canal treatment may present persistent symptomatic or asymptomatic apical periodontitis. Such teeth could be a subject to periapical surgery using a modern technique with an expected good outcome. However, uninstrumented teeth with a need of conventional endodontic treatment can also benefit from such a surgical procedure. In a long-term perspective the orthograde retreatment of the root filling offers a more favorable outcome, 83% versus 72% for periapical surgeryafter 4-6 years. In contrast to that a meta-analysis from Kang et al. revealed a significantly higher success rate for periapical surgery in a short term perspective (less than 4 years) compared ...
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