Section: Free Radicals in the Oral Cavity

Saliva, a heterogeneous fluid comprising proteins, glycoproteins, electrolytes, small organic molecules and compounds transported from the blood, constantly bathes the teeth and oral mucosa. It acts as a cleansing solution, an ion reservoir, a lubricant and a buffer. In addition to its other hostprotective properties, saliva could constitute a first line of defence against free ... Read more

This paper aims to review the role of free radical-induced tissue damage and antioxidant defence mechanisms in inflammatory diseases that involve pathogenic processes similar to the periodontal diseases. There is a clearly defined and substantial role for free radicals or reactive oxygen species (ROS) in periodontitis, but little research has been performed in this area. ... Read more

Background: Numerous in vitro studies have shown that composite materials, commonly used for restorations in conservative dentistry, and in orthodontics to anchor brackets to the tooth enamel, have cytotoxic and genotoxic effects. The study determined expression of p53, p63 and p16, biomarkers useful for predicting potential genotoxicity. Conclusion: The significance of p53, p63 and p16 ... Read more

This study is to evaluate the cytotoxicity of Activ GP and RealSeal sealers in a cell culture system in vitro, and to compare them with traditional AH 26 and Kerr sealers. Conclusion: Freshly mixed RealSeal and Activ GP sealers have lower cytotoxicity than AH 26 sealer and more cytotoxicity than Kerr sealer. When sealers are ... Read more

The presence of the pulpal pressure may cause increasing in fluid filtration and droplet formation in simplified adhesives containing HEMA. The adhesives containing 4-META (G-Bond) may be affected by static phase separation buy by very low osmotic droplets formation and water permeability. The three-step adhesives are less affected by these problems.

The addition of benzalkonium chloride (BAC), an antibacterial agent, to 4-methacryloxyethyl trimellitate anhydride/methyl methacrylate-tri-n-butyl borane (4-META/MMA-TBB) resin, an orthdontic bonding material, confers an antibacterial effect even after immersion in water, and 4-META/MMA-TBB resin containing 0.25% to 0.75% BAC has no significant cytotoxic effect.

This study looked at the difference in the cytotoxicity related to the modes of polymerization of five commercially available orthodontic bonding resins, with and without an oxygen-inhibited layer (OIL), and to evaluate the degree of conversion (DC) of these resins and correlate this to cytotoxicity. Single-cured systems are superior to dual-cured systems in exhibiting comparatively ... Read more

Most cast dental restorations are made from alloys or commercially pure titanium (cpTi). Many orthodontic appliances are also fabricated from metallic materials. It has been documented in vitroand in vivo that metallic dental devices release metal ions, mainly due to corrosion. Those metallic components may be locally and systemically distributed and could play a role ... Read more

Adverse tissue reactions of the gingiva and the periodontium - such as enhanced gingivitis and periodontitis - close to dental cast alloys may be caused by the effects of released metal elements. Tissue reactions depend upon the amounts of elements available which are a function of corrosion rates.

Patients with periodontal disease display increased bacterial antigen PMN number and activity; this proliferation results in high degree of free radical release culminating in heightened oxidative damage to gingival tissues, periodontal ligament and alveolar bone. Damage mediated by free radicals can be mitigated by “ANTIOXIDANT DEFENSE SYSTEM “. Physiological alteration and pathological states produced by ... Read more