Retinal Toxicity Induced by Chemical Agents.

Vision is an important sense for humans, and visual impairment/blindness has a huge impact in daily life. The retina is a nervous tissue that is essential for visual processing since it possesses light sensors (photoreceptors) and performs a pre-processing of visual information. Thus, retinal cell dysfunction or degeneration affects visual ability and several general aspects of the day-to-day of a person's lives. The retina has a blood-retinal barrier, which protects the tissue from a wide range of molecules or microorganisms. However, several agents, coming from systemic pathways, reach the retina and influence its function and survival. Pesticides are still used worldwide for agriculture, contaminating food with substances that could reach the retina. Natural products have also been used for therapeutic purposes and are another group of substances that can get to the retina. Finally, a wide number of medicines administered for different diseases can also affect the retina. The present review aimed to gather recent information about the hazard of these products to the retina, which could be used to encourage the search for more healthy, suitable, or less risky agents.

Root perforations treatment using mineral trioxide aggregate and Portland cements.

PURPOSE: Clinical, radiological and histological evaluation of root perforations treated with mineral trioxide aggregate (MTA) or Portland cements, and calcium sulfate barrier. METHODS: One molar and 11 premolar teeth of a male mongrel dog received endodontic treatment and furcations were perforated with a high-speed round bur and treated with a calcium sulfate barrier. MTA, Portland cement type II (PCII) and type V (PCV), and white Portland cement (WPC) were used as obturation materials. The teeth were restored with composite resin and periapical radiographs were taken. The animal was euthanized 120 days post-surgery for treatment evaluation. RESULTS: Right lower first premolar (MTA), right lower third premolar (PCV), left lower second premolar (MTA), and right lower second premolar (WPC): clinically normal, slightly radio-transparent area on the furcation, little inflammatory infiltrate, and new-bone formation. Left lower third premolar (PCII), right upper first premolar (WPC), right upper third premolar (PCII), and left upper first molar (PCV): clinically normal, radiopaque area on the furcation, and new-bone formation. Right upper second premolar (MTA), left upper second premolar (WPC), left upper third premolar (PCII): presence of furcation lesion, large radiolucent area, and intense inflammatory infiltrate. CONCLUSION: All obturation materials used in this study induced new-bone formation.

Root perforations treatment using mineral trioxide aggregate and Portland cements / Cimentos de agregado trióxido mineral e Portland no tratamento de perfurações radiculares

PURPOSE: Clinical, radiological and histological evaluation of root perforations treated with mineral trioxide aggregate (MTA) or Portland cements, and calcium sulfate barrier. METHODS: One molar and 11 premolar teeth of a male mongrel dog received endodontic treatment and furcations were perforated with a high-speed round bur and treated with a calcium sulfate barrier. MTA, Portland cement type II (PCII) and type V (PCV), and white Portland cement (WPC) were used as obturation materials. The teeth were restored with composite resin and periapical radiographs were taken. The animal was euthanized 120 days post-surgery for treatment evaluation. RESULTS: Right lower first premolar (MTA), right lower third premolar (PCV), left lower second premolar (MTA), and right lower second premolar (WPC): clinically normal, slightly radio-transparent area on the furcation, little inflammatory infiltrate, and new-bone formation. Left lower third premolar (PCII), right upper first premolar (WPC), right upper third premolar (PCII), and left upper first molar (PCV): clinically normal, radiopaque area on the furcation, and new-bone formation. Right upper second premolar (MTA), left upper second premolar (WPC), left upper third premolar (PCII): presence of furcation lesion, large radiolucent area, and intense inflammatory infiltrate. CONCLUSION: All obturation materials used in this study induced new-bone formation.

OBJETIVO: Avaliar clínica, radiológica e histologicamente perfurações radiculares tratadas com MTA e cimentos Portland, com barreira de sulfato de cálcio. MÉTODOS: A amostra foi constituída por 11 dentes pré-molares e um molar de cão macho, sem raça definida. Após tratamento endodôntico realizaram-se perfurações nas furcas com broca esférica de alta rotação e barreira de sulfato de cálcio. Foram utiliados os cimentos MTA, Portland tipo II (CPII), Portland tipo V (CPV) e Portland branco estrutural (CPB). Os dentes foram restaurados com resina composta e submetidos a radiografias periapicais. O animal foi confinado por 120 dias e submetido à eutanásia para avaliações. RESULTADOS: Primeiro pré-molar inferior direito (MTA), terceiro pré-molar inferior direito (CPV), segundo pré-molar inferior esquerdo (MTA) e segundo pré-molar inferior direito (CPB): clinicamente normal; leve área radiotransparente na furca; pequeno infiltrado inflamatório e neoformação óssea. Terceiro pré-molar inferior esquerdo (CPII), primeiro pré-molar superior direito (CPB), terceiro pré-molar superior direito (CPII) e primeiro molar superior esquerdo (CPV): clinicamente normal; área radiopaca na furca; neoformação óssea. Segundo pré-molar superior direito (MTA), segundo pré-molar superior esquerdo (CPB) e terceiro pré-molar superior esquerdo (CPII): clinicamente com lesão na furca; intensa área radiolucida; infiltrado inflamatório intenso. CONCLUSÃO: Todos os cimentos induziram a neoformação óssea.