RESUMO
We determined the relative shear bond strength (SBS) to dentine and cementum and the microleakage of All-Bond 2 universal dental adhesive and OptiBond multi-use filled adhesive. We found that for both systems the SBS increased significantly (p < 0.001) from 15 minutes to 24 hours and 7 days, but there was a slight significant (p < 0.001) weakening towards 30 days. At each time point the shear bond strength of All-Bond 2 and OptiBond were also compared and it was found that OptiBond had significantly higher values (p < 0.05) at all times except at 15 minutes. Optibond also had the lower value for the microleakage (p < 0.001). This study showed that OptiBond had significantly higher shear bond strengths to and lower microleakage in dentine which may increase the longevity of the material in the clinical situation.
Assuntos
Infiltração Dentária/prevenção & controle , Adesivos Dentinários/química , Metacrilatos/química , Cimentos de Resina/química , Dentina/efeitos dos fármacos , Dentina/ultraestrutura , Humanos , Teste de Materiais/métodos , Microscopia Eletrônica de Varredura , Dente Molar/efeitos dos fármacos , Dente Molar/ultraestrutura , Estresse Mecânico , Propriedades de Superfície , Resistência à TraçãoRESUMO
The antibacterial properties of honey against medically important bacteria have been well documented but this information is not available for the oral bacteria and specifically for the oral streptococci. We determined the minimal inhibitory concentration (MIC) of honey for oral streptococci. Honey had a MIC of 25 per cent (vol/vol) for the bacteria tested with the exception of Streptococcus anginosus and Streptococcus oralis which were inhibited by 17 per cent (vol/vol) and 12 per cent (vol/vol) honey respectively. The hypertonic sugar control had a MIC of 25 per cent (vol/vol) for all the bacteria tested. Although the results of this study indicate that there could be other antibacterial agents present in the honey, it may be assumed that the hypertonic sugar concentration played an important role in this activity.
Assuntos
Antibacterianos/farmacologia , Mel , Boca/microbiologia , Streptococcus oralis/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Testes de Sensibilidade MicrobianaRESUMO
Various fruit juices with relatively low pH are known to have erosive effects on human tooth enamel in a reasonably short time. Honey, also with a relatively low pH, could do the same, but scanning electron microscopy showed no erosion of enamel by honey over a period of 30 min, neither did Knoop microhardness tests show any deterioration of enamel structure. The absence of any effect could be only partially attributed to the calcium, phosphorus and fluoride levels in honey.
