Mariana Ferreira Leite

Diabetes induces metabolic alterations in dental pulp.

Diabetes can interfere in tissue nutrition and can impair dental pulp metabolism. This disease causes oxidative stress in cells and tissues. However, little is known about the antioxidant system in the dental pulp of diabetics. Thus, it would be of importance to study this system in this tissue in order to verify possible alterations indicative of oxidative stress. The aim of this study was to evaluate some parameters of antioxidant system of the dental pulp of healthy (n = 8) and diabetic rats (n = 8). Diabetes was induced by streptozotocin in rats. Six weeks after diabetes induction, a pool of the dental pulp of the 4 incisors of each rat (healthy and diabetic) was used for the determination of total protein and sialic acid concentrations and catalase and peroxidase activities. Data were compared by a Student t test (p <or= 0.05). Dental pulps from both groups presented similar total protein concentrations and peroxidase activity. Dental pulps of diabetic rats exhibited significantly lower free, conjugated, and total sialic acid concentrations than those of control tissues. Catalase activity in diabetic dental pulps was significantly enhanced in comparison with that of control pulps. The result of the present study is indicative of oxidative stress in the dental pulp caused by diabetes. The increase of catalase activity and the reduction of sialic acid could be resultant of reactive oxygen species production.

Does the neuromotor abnormality type affect the salivary parameters in individuals with cerebral palsy

BACKGROUND Previous studies reported alterations in salivary flow rate and biochemical parameters of saliva in cerebral palsy (CP) individuals; however, none of these considered the type of neuromotor abnormality among CP individuals, thus it remains unclear whether the different anatomical and extended regions of the brain lesions responsible for the neurological damage in CP might include disruption of the regulatory mechanism of saliva secretion as part of the encephalopathy. The aim of this study was to evaluate salivary flow rate, pH and buffer capacity in saliva of individuals with CP, aged 3-16 years, with spastic neuromotor abnormality type and clinical patterns of involvement. METHODS Sixty-seven individuals with CP spasticity movement disorder, were divided in two groups according to age (3-8- and 9-16-years-old) and compared with 35 sibling volunteers with no neurological damage, divided in two groups according to age (3-8- and 9-16-years-old). Whole saliva was collected under slight suction and pH and buffer capacity were determined using a digital pH meter. Buffer capacity was measured by titration using 0.01N HCL, and flow rate was calculated in ml/min. RESULTS In both age groups studied, whole saliva flow rate, pH and buffer capacity were significantly lower in the spastic CP group (P<0.05). The clinical patterns of involvement did not influence the studied parameters. CONCLUSION These findings show that individuals with spastic cerebral palsy present lower salivary flow rate, pH and buffer capacity that can increase the risk of oral disease in this population.

In vivo astaxanthin treatment partially prevents antioxidant alterations in dental pulp from alloxan-induced diabetic rats

AIM To evaluate the effect of astaxanthin on antioxidant parameters of dental pulp from diabetic rats. The hypothesis tested was that supplementation of diabetic rats with astaxanthin might eliminate, or at least attenuate, the defect in their antioxidative status. METHODOLOGY Wistar rats (n=32) were divided into four groups: untreated control, treated control, untreated diabetic and treated diabetic rats. A prophylactic dose of astaxanthin (20 mg kg(-1) body weight) was administered daily by gavage for 30 days. On day 23, diabetes was induced by injection of alloxan (60 mg kg(-1) body weight). After 7 days of diabetes induction, the rats were killed, and pulp tissue from incisor teeth removed. Superoxide dismutase (SOD), catalase, glutathione peroxidase (GPx) and reductase activities were determined. Data were compared by anova and the Newman-Keuls test (P<0.05). RESULTS Diabetes caused a reduction in SOD, GPx and reductase activity in dental pulp tissue. Astaxanthin had no effect on SOD and catalase activities; however, it stimulated GPx in control and diabetic rats. CONCLUSIONS Diabetes altered the antioxidant system in dental pulp tissue; astaxanthin partially improved the diabetic complications.

Salivary osmolality and hydration status in children with cerebral palsy

BACKGROUND Unstimulated whole salivary parameters have been identified as potential markers of hydration status. Reduced salivary flow rate and increased salivary osmolality have been shown to be useful to identify dehydration, even when minimal loss of body water occurs. This study aimed to evaluate whether unstimulated salivary flow rate and salivary osmolality from individuals with cerebral palsy correlate with plasma and urine osmolality. METHODS Thirty-five male and female children, aged 9-13 years old, diagnosed with cerebral palsy were compared to 27 nondisabled children (10-12 years old). Unstimulated whole saliva was collected under slight suction and salivary flow rate (ml/min) was calculated. Plasma without venostasis and urine were also collected. Salivary, plasma and urine osmolality were measured using a freezing point depression osmometer. RESULTS Cerebral palsy children presented a reduction in salivary flow rate (50%) compared to the control group (P < 0.01). Moreover, an increase in salivary (50%), plasma (3%), and urine osmolality (20%) was also observed in the cerebral palsy children compared to the control group (P < 0.01). Salivary flow rate was negatively correlated with the salivary, plasma and urine osmolality (P < 0.01). Salivary osmolality correlated positively with plasma and urine osmolality (P < 0.01). CONCLUSION Cerebral palsy children seem to present impaired adequate hydration status. Since the possible hypohydration condition may be reflected in saliva fluid, which could compromise the protective function exerted by saliva, the earlier this condition is identified the greater the chances of administering preventive measures. Moreover, salivary osmolality is a reliable parameter that reflects changes in plasma and urine.

Autonomic nervous system in individuals with cerebral palsy: a controlled study.

BACKGROUND Disturbances in homeostatic functions have been observed in individuals with cerebral palsy (CP), possibly resulting from autonomic dysfunction. Salivary flow rate and saliva composition are controlled by the autonomic nervous system, and CP individuals exhibit alterations in salivary parameters that suggest autonomic impairment. This study aimed to investigate cardiac parameters as indicative of autonomic disturbances, possibly associated with salivary changes observed in CP individuals. METHODS Ninety individuals with CP were compared with 35 sibling volunteers with no neurological damage (CG). Twenty-four-hour ECG/Holter monitoring (SEER(®) Light; GE Medical Systems, Milwaukee, WI, USA) and 12-lead electrocardiographic recordings were performed on the CP and control groups. Total saliva was collected, and the salivary flow rate and total protein concentration were determined. RESULTS  Cerebral palsy (CP) individuals presented a significant reduction in salivary flow rate (P < 0.01) and increased protein concentrations (P < 0.01) compared to CG. Twenty-four-hour Holter ECG analysis showed differences for high frequency (HF), low frequency (LF) and LF/HF ratio between the groups, with the CP group presenting higher HF and LF values and lower LF/HF. Electrocardiographic parameters showed a statistically significant difference for heart rate, and its correlates, and mean corrected QT interval between the groups studied (P < 0.05). Snoring was frequent among CP patients. ECG and autonomic changes were independently associated with CP. CONCLUSION Individuals with cerebral palsy present cardiovascular changes principally manifested as disturbed sympathovagal balance. These autonomic dysfunctions could contribute to the salivary changes observed.

Salivary flow rate and biochemical composition analysis in stimulated whole saliva of children with cystic fibrosis

OBJECTIVE It is recognized that cystic fibrosis (CF) patients present a risk for oral diseases, since it affects exocrine glands, and the treatment consists of a carbohydrate-rich diet. Recognizing the protective function of saliva on maintaining oral health, the aim of the study was to evaluate salivary parameters in stimulated whole saliva from children with CF. METHODS A case-control study was conducted comparing stimulated whole saliva of healthy (n=28; control group) and CF children (n=21; experimental group). Salivary flow rate, initial pH, buffer capacity (total and in each range of pH), total protein and sialic acid (total, free, and conjugated) concentration, α-amylase and salivary peroxidase activities were evaluated. Data were compared by two-tailed Student t test (95% CI; p ≤ 0.05). RESULTS CF patients presented a significant reduction in salivary parameters compared with the control group (p ≤ 0.05): salivary flow rate (36%), buffer capacity (pH range from 6.9 to 6.0), sialic acid concentration (total 75%, free 61%, and conjugated 83%); α-amylase and salivary peroxidase activities (55%). Additionally, a significant increase in total protein concentration (180%) of stimulated whole saliva from CF patients was verified compared with the control group (p ≤ 0.05). CONCLUSION Children with CF presented significant changes in salivary composition, including salivary flow rate, buffering capacity and protective proteins of the oral cavity, compared with children without CF.

Compromised salivary parameters of children with juvenile idiopathic arthritis

OBJECTIVE To evaluate the salivary parameters of individuals with juvenile idiopathic arthritis (JIA) and determine if there is a correlation with the simplified oral hygiene index (OHI-S). STUDY DESIGN Stimulated whole saliva was collected from children, aged 6 to 12 years, with JIA (n = 36) and compared with saliva from a control group (CG) composed of healthy children matched by demographic characteristics (n = 36). Salivary parameters evaluated were amylase and peroxidase activities, calcium, phosphate, and total sialic acid concentration. Data were compared by two-tailed Students t test, and salivary parameters were evaluated for correlations with OHI-S by Spearmans correlation. RESULTS The JIA group had a statistically significant reduction in all salivary parameters: α-amylase (20%) (CG, 9.84 ± 4.23; JIA 4.80 ± 3.10) and peroxidase (55%) (CG, 35.05 ± 14.97; JIA, 15.78 ± 6.44) activities, total sialic acid (25%) (CG, 0.024 ± 0.01; JIA, 0.010 ± 0.04), calcium (13%) (CG, 6.26 ± 2.26; JIA, 5.44 ± 2.26) and phosphate (50%) (CG, 10.88 ± 1.49; JIA, 5.45 ± 0.88) concentration compared with the CG (P ≤ .05). There were no significant correlations between the salivary parameters and OHI-S in either group. CONCLUSION JIA patients showed a reduction of different salivary parameters involved in maintaining oral health.

Exploring some aspects associated with dentine hypersensitivity in children.

Background. The etiology of dentine hypersensitivity (DH) is still inconclusive and there are few studies concerning it in children. Aim. To evaluate clinical, dietary, and salivary variables in children with DH complaints. Design. Forty-eight children were asked about DH. Data regarding dietary habits were collected from the childrens parents and an examination was performed to determine dental erosion. Dental biofilm was estimated by oral hygiene status, according to Greene and Vermillions Simplified Oral Hygiene Index (OHI-S). Whole saliva was collected under mechanical stimulation and evaluated salivary flow rate, initial pH, buffer capacity, and calcium and phosphate concentrations. The temperature of soft drinks, drinking method, sense of bitter taste, and other variables were also determined. Possible factors associated with DH were analyzed by univariate and multiple Poisson regression analyses. The prevalence ratio (PR) values and 95% confidence intervals (95% CI) were calculated. Results. DH was associated with the presence of dental erosion (PR; 95% CI = 2.23; 1.05 to 4.71) and salivary flow rate (2.49; 1.05 to 5.91). When the presence of erosion was not included, other variables were retained as follows: bitter taste (2.36; 1.38 to 4.03), OHI-S (0.47; 0.23 to 0.97). Conclusion. DH in children is associated with factors related to dental erosion.

Efeito do Gênero (Masculino e Feminino) sobre a Cárie Dentária e Parâmetros Salivares de Crianças

Objetivo: avaliar o indice de carie dentaria e parâmetros salivares comparando meninos e meninas.Metodos: a saliva total estimulada mecanicamente com parafilm foi coletada de 46 criancas saudaveis, com quatro a seis anos de idade, sendo 24 meninos e 22 meninas. As criancas foram divididas em subgrupos de acordo com o genero (meninos e meninas) e presenca de carie dentaria (cavidades de carie, CC; livres de carie, CF). A carie dentaria foi avaliada usando os criterios da OMS e Kappa=0,87. O grupo CC foi definido pela presenca de no minimo tres superficies com necessidade de restauracao e o grupo CF pela ausencia de dentes com lesoes de carie clinicamente detectaveis (ceo-s=o). Os parâmetros salivares avaliados foram o fluxo salivar, a concentracao de proteina total e a atividade enzimatica da peroxidase. Os resultados foram comparados por teste t de Student e Analise de Variância e teste de Tukey para contraste de media (p≤0,05). Resultados: criancas com carie dentaria apresentaram reducao de 33% do fluxo salivar comparadas com criancas sem carie dentaria (p≤0,05). Entre as criancas com carie dentaria, as meninas apresentaram maior indice de carie dentaria comparadas com os meninos (98%, p≤0.05). As meninas apresentaram diferencas salivares mais pronunciadas comparados aos meninos, com maior concentracao de proteina total e menor fluxo salivar e atividade da peroxidase (p≤0,05). Conclusao: o estudo sugere que o genero pode influenciar o desenvolvimento de carie dentaria e parâmetros salivares de criancas... Objective: To evaluate the dental caries index and salivary parametersin boys and girls. Method: Whole stimulated saliva by chewing Parafilm® was collected from 46 healthy children (24 boys and 22 girls) aged 4 to 6 years. The children were assigned to subgroups according to gender (boys andgirls) and dental caries (CC u caries cavities; CF u caries free). Dentalcaries was evaluated using the WHO criteria and kappa=0.87. The CC group was defined by the presence of at least three surfaces requiring restoration while the CF group was characterized by the absence of clinically detectable caries (ceo-s=0). The following salivary parameters were evaluated: salivary flow, total protein concentration andperoxidase enzymatic activity. The results were compared by theStudentAEs t-test, ANOVA and TukeyAEs multiple-comparison test (p≤0.05).Results: Children with dental caries presented a 33% reduction of salivary flow compared to the caries-free children (p≤0.05). Among the children with dental caries, the girls had a greater caries index than the boys (98%, p≤0.05). The girls presented more accentuated salivary parameters than boys, with greater total protein concentration, lower salivary flow and lower peroxidase activity (p≤0.05).Conclusion: This study suggests that gender might influence the development of dental caries and the salivary parameters in children...