Bruno das Neves Cavalcanti

Urinary levels of catecholamines among individuals with and without sleep bruxism

IntroductionSleep bruxism (SB) is characterized by repetitive and coordinated mandible movements and non-functional teeth contacts during sleep time. Although the etiology of SB is controversial, the literature converges on its multifactorial origin. Occlusal factors, smoking, alcoholism, drug usage, stress, and anxiety have been described as SB trigger factors. Recent studies on this topic discussed the role of neurotransmitters on the development of SB.ObjectiveThus, the purpose of this study was to detect and quantify the urinary levels of catecholamines, specifically of adrenaline, noradrenaline and dopamine, in subjects with SB and in control individuals.Materials and methodsUrine from individuals with SB (n = 20) and without SB (n = 20) was subjected to liquid chromatography. The catecholamine data were compared by Mann–Whitney’s test (p ≤ 0.05).ResultsOur analysis showed higher levels of catecholamines in subjects with SB (adrenaline = 111.4 µg/24 h; noradrenaline = 261,5 µg/24 h; dopamine = 479.5 µg/24 h) than in control subjects (adrenaline = 35,0 µg/24 h; noradrenaline = 148,7 µg/24 h; dopamine = 201,7 µg/24 h). Statistical differences were found for the three catecholamines tested.ConclusionIt was concluded that individuals with SB have higher levels of urinary catecholamines.

Citotoxicidade de substâncias liberadas de sistemas adesivos convencional e auto-condicionante sobre fibroblastos de polpa humana

the use of adhesives for direct dental pulp capping is not advisable, due to its harmful effects to the tissue. however, new adhesive systems are often released, and self-etching systems seem to be less toxic than conventional ones. the purpose of this study was to compare the in vitro cytotoxicity of substances leached from calcium hydroxide and two adhesive systems on human dental pulp fibroblasts. Cell culture media conditioned by Calcium Hydroxide (CH), Single Bond (SB), Clearfill Protect Bond primer (CP) or Clearfill Protect Bond resin (CB) were applied to human pulp fibroblasts. Fresh cell culture medium was used in the Control group. the number of viable cells was obtained through the mtt reduction assay. Data were compared by ANOVA and Tukey’s test (p≤0.05). The mean number of viable cells was 3.9x103(±0.75) for the control group, which was similar to those found in the CH group (4.31x103±0.87). Statistical differences were found among the groups (p<0.001), with the cell viability decreasing significantly with SB (0.09x103±0.06) and CP (0.28x103±0.08) when compared to CH and control groups. CB (2.37x103±0.72) was significantly less cytotoxic than CP and SB, but more cytotoxic than CH. It was concluded that Single Bond and Clearfill Protect Bond primer release substances that decrease cell viability of human dental pulp cells in culture. according to this study the use of bonding systems for direct pulp capping is not recommended, since they are cytotoxic.