RESUMO
AIM: The present randomized, controlled prospective study evaluated the histomorphological response of human dental pulps capped with two grey mineral trioxide aggregate (MTA) compounds. METHODOLOGY: Pulp exposures were performed on the occlusal floor of 40 human permanent pre-molars. The pulp was capped either with ProRoot (Dentsply) or MTA-Angelus (Angelus) and restored with zinc oxide eugenol cement. After 30 and 60 days, teeth were extracted and processed for histological examination and the effects on the pulp were scored. The data were subjected to Kruskal-Wallis and Conover tests (alpha = 0.05). RESULTS: In five out of the 40 teeth bacteria were present in pulp tissue. No significant difference was observed between the two materials (P > 0.05) in terms of overall histological features (hard tissue bridge, inflammatory response, giant cells and particles of capping materials). Overall, 94% and 88% of the specimens capped with MTA-Angelus and ProRoot, respectively, showed either total or partial hard tissue bridge formation (P > 0.05). CONCLUSIONS: Both commercial materials ProRoot (Dentsply) and MTA-Angelus (Angelus) produced similar responses in the pulp when used for pulp capping in intact, caries-free teeth.
Assuntos
Compostos de Alumínio/uso terapêutico , Compostos de Cálcio/uso terapêutico , Cimentos Dentários/uso terapêutico , Capeamento da Polpa Dentária , Exposição da Polpa Dentária/terapia , Óxidos/uso terapêutico , Silicatos/uso terapêutico , Adulto , Polpa Dentária/efeitos dos fármacos , Polpa Dentária/microbiologia , Necrose da Polpa Dentária/patologia , Sensibilidade da Dentina/patologia , Dentina Secundária/patologia , Combinação de Medicamentos , Seguimentos , Células Gigantes/patologia , Humanos , Odontoblastos/patologia , Estudos Prospectivos , Pulpite/patologia , Método Simples-Cego , Cimento de Óxido de Zinco e Eugenol/uso terapêuticoRESUMO
OBJECTIVES: To compare the response of human dental pulp capped with a mineral trioxide aggregate (MTA) and Ca(OH)2 powder. METHODS AND MATERIAL: Pulp exposures were performed on the occlusal floor of 40 permanent premolars. The pulp was then capped with either Ca(OH)2 powder (CH) or MTA and restored with resin composite. After 30 days (groups CH30 and MTA30) and 60 days (groups CH60 and MTA60), the teeth were extracted and processed for HE and categorized in a histological score system. The data were subjected to Kruskal-Wallis and Conover tests (alpha = 0.05). RESULTS: In regard to dentin bridge formation, CH30 showed a tendency towards superior performance compared to MTA30 (p > 0.05), although the products showed comparable results at day 60. In the item "Inflammation" and "General State of the Pulp" (p > 0.05), CH showed a tendency towards presenting a higher inflammatory response. In the item "Other Pulpal Findings," MTA and Ca(OH)2 showed equal and excellent performance after 30 and 60 days (p > 0.05). CONCLUSION: After 30 days, Ca(OH)2 powder covered with calcium hydroxide cement showed faster hard tissue bridge formation compared to MTA. After 60 days, Ca(OH)2 powder or MTA materials showed a similar and excellent histological response with the formation of a hard tissue bridge in almost all cases with low inflammatory infiltrate.
Assuntos
Compostos de Alumínio/uso terapêutico , Compostos de Cálcio/uso terapêutico , Hidróxido de Cálcio/uso terapêutico , Materiais Dentários/uso terapêutico , Capeamento da Polpa Dentária/métodos , Polpa Dentária/efeitos dos fármacos , Óxidos/uso terapêutico , Substâncias Protetoras/uso terapêutico , Silicatos/uso terapêutico , Adolescente , Adulto , Dente Pré-Molar , Resinas Compostas , Polpa Dentária/patologia , Exposição da Polpa Dentária/terapia , Restauração Dentária Permanente , Dentina Secundária/efeitos dos fármacos , Dentina Secundária/patologia , Combinação de Medicamentos , Células Gigantes/patologia , Humanos , Macrófagos/patologia , Teste de Materiais , Pulpite/patologia , Fatores de Tempo , Odontalgia/etiologiaRESUMO
This study was conducted to observe the response of dogs' dental pulp to mineral trioxide aggregate (MTA) and a calcium hydroxide cement when used as pulp capping materials. After the pulps of 30 teeth were exposed, they were capped with either MTA or a calcium hydroxide cement. Histological analysis was performed 2 months after treatment. Results showed a healing process with complete tubular dentin bridge formation and no inflammation in any of the pulps capped with MTA. On the other hand, only five specimens from the calcium hydroxide cement group formed a complete dentin bridge. In this experimental group, pulp inflammation was observed in all but three cases. In conclusion, MTA exhibited better results than the calcium hydroxide cement for the capping of the pulp in dogs.
Assuntos
Compostos de Alumínio/efeitos adversos , Compostos de Cálcio/efeitos adversos , Hidróxido de Cálcio/efeitos adversos , Cimentos Dentários/efeitos adversos , Capeamento da Polpa Dentária/métodos , Polpa Dentária/efeitos dos fármacos , Minerais/efeitos adversos , Óxidos/efeitos adversos , Silicatos/efeitos adversos , Animais , Dentina Secundária/metabolismo , Cães , Combinação de Medicamentos , Pulpite/induzido quimicamente , Estatísticas não ParamétricasRESUMO
We reported previously that equine-2 influenza A virus (H3N8) had evolved into two genetically and antigenically distinct "Eurasian" and "American" lineages. Phylogenetic analysis, using the HA1 gene of more recent American isolates, indicated a further divergence of these viruses into three evolution lineages: A South American lineage, a Kentucky lineage, and a Florida lineage. These multiple evolution pathways were not due to geographic barriers, as viruses from different lineages co-circulated. For the Kentucky lineage, the evolution rate was estimated to be 0.89 amino acid substitutions per year, which agreed with the previously estimated rate of 0.8. For the South American lineage, the evolution rate was estimated to be only 0.27 amino acid substitutions per year. This low evolution rate was probably due to a unique alternating Ser138 to Ala138 substitutions at antigenic site A. For the Kentucky lineage, there was a preference for sequential nonsynonymous substitutions at antigenic site B, which was also a "hot spot" for amino acid substitutions. Convalescent sera had minimal cross-reactivity to viruses of different lineages, indicating antigenic distinctions among these viruses. In contrast to human H3N2 viruses, our results suggested that the evolution of equine-2 influenza virus resembled the multiple evolution pathways of influenza B virus.
Assuntos
Evolução Molecular , Vírus da Influenza A Subtipo H3N8 , Vírus da Influenza A/genética , Sequência de Aminoácidos , Substituição de Aminoácidos , Animais , Antígenos Virais/genética , Florida , Genes Virais , Hemaglutininas Virais/genética , Cavalos , Humanos , Vírus da Influenza A/classificação , Vírus da Influenza A/imunologia , Vírus da Influenza A/isolamento & purificação , Kentucky , Dados de Sequência Molecular , América do Sul , Fatores de Tempo , Proteínas Virais/genética , Proteínas Virais/imunologiaRESUMO
This study was conducted to observe the healing process of intentional lateral root perforation repaired with mineral trioxide aggregate (MTA). Forty-eight root canals of dogs' teeth were instrumented and filled. After partial removal of the filling, an intentional perforation was made with a bur in the lateral area of the root. The perforations were repaired with MTA or Sealapex (control group). Histological analysis occurred 30 and 180 days after treatment. Results showed no inflammation and deposition of cementum over MTA in the majority of the specimens. In the 180-day period, Sealapex exhibited chronic inflammation in all the specimens and slight deposition of cementum over the material in only three cases. In conclusion, MTA exhibited better results than the control group.
Assuntos
Compostos de Alumínio/uso terapêutico , Compostos de Cálcio/uso terapêutico , Cavidade Pulpar/lesões , Óxidos/uso terapêutico , Materiais Restauradores do Canal Radicular/uso terapêutico , Silicatos/uso terapêutico , Animais , Hidróxido de Cálcio/uso terapêutico , Tecido Conjuntivo/patologia , Cemento Dentário/patologia , Cavidade Pulpar/patologia , Cães , Combinação de Medicamentos , Seguimentos , Células Gigantes/patologia , Inflamação , Macrófagos/patologia , Ligamento Periodontal/patologia , Preparo de Canal Radicular/instrumentação , Salicilatos/uso terapêutico , Raiz Dentária/lesões , CicatrizaçãoRESUMO
Considering several reports about the similarity between the chemical compositions of the mineral trioxide aggregate (MTA) and Portland cement (PC), the subject of this investigation was to analyze the behavior of dog dental pulp after pulpotomy and direct pulp protection with these materials. After pulpotomy, the pulp stumps of 26 roots of dog teeth were protected with MTA or PC. Sixty days after treatment, the animal was sacrificed and the specimens removed and prepared for histomorphological analysis. There was a complete tubular hard tissue bridge in almost all specimens. In conclusion, MTA and PC show similar comparative results when used in direct pulp protection after pulpotomy.
Assuntos
Compostos de Alumínio , Compostos de Cálcio , Cimentos Dentários , Capeamento da Polpa Dentária/métodos , Combinação de Medicamentos , Óxidos , Pulpotomia , Cimento de Silicato , Silicatos , Cicatrização , Animais , Dentina Secundária/crescimento & desenvolvimento , Cães , Estatísticas não ParamétricasRESUMO
The subject of this study was to observe the rat subcutaneous connective tissue reaction to implanted dentin tubes filled with mineral trioxide aggregate, Portland cement or calcium hydroxide. The animals were sacrificed after 7 or 30 days and the undecalcified specimens were prepared for histological analysis with polarized light and Von Kossa technique for mineralized tissues. The results were similar for the studied materials. At the tube openings, there were Von Kossa-positive granules that were birefringent to polarized light. Next to these granulations, there was an irregular tissue like a bridge that was Von Kossa-positive. The dentin walls of the tubes exhibited in the tubules a structure highly birefringent to polarized light, usually like a layer and at different depths. The mechanism of action of the studied materials has some similarity.
Assuntos
Compostos de Alumínio/farmacologia , Compostos de Cálcio/farmacologia , Hidróxido de Cálcio/farmacologia , Cimentos Dentários/farmacologia , Dentina Secundária/induzido quimicamente , Dentina/efeitos dos fármacos , Óxidos/farmacologia , Silicatos/farmacologia , Pele/patologia , Animais , Núcleo Celular/ultraestrutura , Corantes , Tecido Conjuntivo/patologia , Dentina/patologia , Dentina Secundária/patologia , Combinação de Medicamentos , Fibroblastos/patologia , Corantes Fluorescentes , Células Gigantes/patologia , Humanos , Microscopia de Polarização , Neutrófilos/patologia , Ratos , Fatores de TempoRESUMO
This study was conducted to observe the rat subcutaneous connective tissue reaction to the implanted dentin tubes filled with calcium hydroxide or mineral trioxide aggregate. The animals were sacrificed after 7 and 30 days, and the specimens were prepared for morphological study. Some undecalcified specimens were prepared for histological analysis with polarized light and Von Kossa technique for calcium. The results were similar for both studied materials. At the tube openings, there were Von Kossa-positive granules that were birefringent to polarized light. Next to these granulations, there was an irregular tissue like a bridge that was Von Kossa-positive. The dentin walls of the tubes exhibited in the tubules a structure highly birefringent to polarized light, usually like a layer and at different depths. It is possible that the mechanism of action of both materials has some similarity.
Assuntos
Compostos de Alumínio/farmacologia , Compostos de Cálcio/farmacologia , Hidróxido de Cálcio/farmacologia , Tecido Conjuntivo/efeitos dos fármacos , Óxidos/farmacologia , Materiais Restauradores do Canal Radicular/farmacologia , Silicatos/farmacologia , Animais , Dentina , Combinação de Medicamentos , Humanos , Implantes Experimentais , RatosRESUMO
This study was conducted to observe the reaction of apical tissues of dogs' teeth after root canal filling with gutta-percha and mineral trioxide aggregate (MTA) or a glass ionomer (Ketac-Endo) as a sealer. The root canals were instrumented and filled by the lateral condensation technique with the sealers studied. Animals were killed 6 months later, and the specimens were removed and prepared for histological analysis. Results showed no inflammatory reaction of apical tissue and total closure of the apical foramen of all the teeth sealed with MTA. The teeth sealed with Ketac-Endo showed two cases of partial closure and different degrees of chronic inflammatory reaction. In conclusion, MTA exhibited better biological properties than Ketac-Endo.
Assuntos
Compostos de Alumínio/farmacologia , Compostos de Cálcio/farmacologia , Cimentos de Ionômeros de Vidro/farmacologia , Óxidos/farmacologia , Tecido Periapical/efeitos dos fármacos , Materiais Restauradores do Canal Radicular/farmacologia , Silicatos/farmacologia , Ápice Dentário/efeitos dos fármacos , Animais , Cemento Dentário/efeitos dos fármacos , Dentina Secundária/efeitos dos fármacos , Cães , Combinação de MedicamentosRESUMO
Some divergencies in the literature about periodontal healing after surgical injury stimulated the development of this experiment. The root canals of dogs' teeth were negotiated and filled by the lateral condensation technique with two kinds of sealers: Sealapex and zinc oxide-eugenol cement. In the second session, the bone tissue was exposed and one cavity was made at the apical third of the root and another at the border between the coronal and middle thirds, both penetrating into the root canal. Six months later the animals were sacrificed and the specimens prepared for histopathologic analysis. The results showed that the kind of filling material and the level of the periodontal wound exposing the root canal can influence the healing process.