[Velocity of erosion and factors that modify human tooth demineralization in vitro]. / Velocidad de erosión y factores que modifican la desmineralización de dientes humanos in vitro.

Velocity of erosion on human teeth exposed to a carbonated beverage as a function of time and temperature has been studied in vitro, as well as the effect of the experimental formation of a acquired pellicle and the influence of the inclusion of either F or saliva on the dissolving capacity of beverage. During the first stage of exposition, erosion as a function of time showed a biphasic curve, being the rate low during the first 10 minutes time; thereafter, velocity increased and remained stable until the 60 minute incubation period finished. At the second stage, demineralization followed a monophasic curve, displaying a stable rate until the end of it. At the initial stage, molar ratio Ca/P was much less than that corresponding to hydroxyapatite (approximately 1.67); however, as exposition to erosive beverage was prolonged, the former ratio reached values compatible with this mineral species. F or saliva incorporation together with the experimental formation of the acquired pellicle significatively reduced beverage demineralizing capacity (p < 0.0001). This finding introduces the possibility of attenuating such erosive capacity of carbonated beverages by including not excessively toxic fluoride quantities.

Evolution of saliva and serum components in patients with oral candidosis topically treated with Ketoconazole and Nystatin.

The present study involves the analysis of some saliva components (SC) and serum components in patients with oral candidosis topically treated with Ketoconazole 2% (K) or Nystatin 100,000 IU (N). Twenty-four male and female patients, age range 39-82 years, were included in the study. A double-blind study was undertaken in which the patients were divided into 2 treatment groups. These groups were compared with a control group (CG) of 16 healthy patients, both male and female, age-matched with the treated groups. The parameters evaluated were oral mucous membrane lesion index (MLI), CFU of Candida, saliva flow rate, protein-bound Fe (Fe-prot), Fe-prot binding capacity (Fe-prot cap), IgAs, peroxidase activity (PA), hypothiocyanite and thiocyanite. The values of Candida CFU and MLI were significantly reduced in patients treated with K and N. The pre-treatment values of SC as compared to the CG revealed a reduction in Fe-prot and Fe-prot cap. These parameters reach values similar to control towards the end of the treatment. The PA was significantly higher in candidosis patients and fell to control values with treatment. The other SC and serum components did not exhibit significant differences with the CG. Patients with oral candidosis treated locally exhibit not only an improvement in clinical manifestations but also a return to control values of altered SC.

In vitro erosive capacity of some fruit juices and soft or low alcoholic strength beverages on human teeth.

The in vitro erosive capacity of different fruit juices and soft or low alcoholic strength beverages (n = 50) on human teeth was examined. The end-point was the amount of calcium and phosphate released into the medium following incubation with the test substance. Overall, the erosive capacity rose as the pH of the products fell. A statistically significant negative correlation was found between the dissolving effect and pH or the modulating action in the presence of acids (r = -0.69282 and -0.63708 respectively; p = 0.0000). Conversely, there was no association between erosive capacity and concentrations of calcium, phosphate or fluoride. Considered overall, sport drinks exhibited the greatest demineralizing effect. Beer had the lowest dissolving action. Most of the drinks manufactured with grapefruit, lime or lemon/lime proved to be more erosive than those prepared with apple or peach. Susceptibility to erosion was virtually the same for all types of teeth and dental surfaces. The cervical portion which harbours the anatomical neck underwent dissolution more readily than the coronary portion (p < 0.001). The erosive capacity of the fruit juices and beverages tested is related to their pH. However, a strict relation between free H+ and demineralizing action was not found, probably due to the influence of other factors not considered in the present study.

[Oral health status evaluation of pre-school children: longitudinal epidemiologic study (1993-1994), Córdoba, Argentina]. / Evaluación del estado de salud bucodental en preescolares: estudio epidemiológico longitudinal (1993-1994), Córdoba, Argentina.

A one-year longitudinal survey was carried out on a sample of the Cordoba City 4-year old kindergarten population (n = 820); so as to determine the role of several variables upon the incidence of caries. The dmf-t, dmf-s, oral hygiene and oral health indexes as well as incidence rates and caries relative risks of caries were inversely related to the socioeconomic level (SEL) of the children involved. Thus in the SEL III (typical proletariat, non-typical proletariat and sub-proletariat) children, the relative risk of caries was almost five times higher (RR = 4.9) than in the SEL I (entrepreneureal and managerial bourgeoisie) children. In SEL I, almost all new lesions occurred on smooth surfaces (61.2%), while in SEL III the molar occlusal faces were mainly affected (66.3%). Daily sugar intake was higher in SEL III children but experience of caries showed poor correlation to the amount (r = 0.40) and frequency (r = 0.52) of carbohydrate intake. No significant interlevel differences were observed in the biochemical salivary parameters analyzed. Assisted toothbrushing and fluoride topications strongly lowered the incidence of caries among SEL III children, also making the corresponding rates fall almost to SEL I values (0.31, 0.23 and 0.22 vs. 0.21). In conclusion, SEL III children should be treated prophylactically with effective preventive measures, because of their susceptibility to caries. Such preventive measures include assisted toothbrushing and fluoride topications.

Effects of xylitol, sorbitol and fluoride mouthrinses on glucose clearance in adolescents.

The present work describes and analyzes the results of a randomized clinical trial on 98 healthy adolescents (age 18 +/- 0.7 years) in order to evaluate the effects of a 14 days treatment with mouthrinses containing xylitol (0.2%; 0.5% and 1%), sorbitol (1%), NaF (0.1% respectively) on salivary glucose clearance. In all volunteers oral glucose clearance followed an exponential curve as a function of time, which fitted almost exactly to the equation log Ct = log Co - bt from 1 to 16 minutes after sugar rinsing. Xylitol treatment provoked an increase in oral glucose clearance, which was proportional to its concentration in the mouthrinse formula. The average AUC (area under curve) decrease was 9.1% in subjects rinsing with 0.2% xylitol; 21.5% with 0.5% xylitol and 40.0% with 1% xylitol. 1% sorbitol or 0.1% NaF did not modify any of the pharmacokinetical parameters over the same treatment time. The mouthrinses containing 1% xylitol and 0.1% NaF produced the same results as 1% xylitol alone on oral glucose clearance. No significant changes in the salivary flow rate nor in oral health parameters were observed concomitant to the faster oral glucose clearance by xylitol treatment. Since the sugars salivary clearance is part of a process intended to prevent dental caries, our results suggest that xylitol adds another mechanism of action to its well known cariostatic and anticaries properties.

Evaluation of serum and saliva components in candidosis patients.

The serum and saliva components of 36 chronic Candidosis patients, both male and female, ages 38-82 who attended the Department of Clinical Stomatology were studied. Total Mucous Lesion Index (TMLI) and salivary flow rate were assessed. The following parameters were evaluated: iron bound protein, unsaturated iron binding capacity, peroxidase activity, protein content, OSCN-, SCN-, IgAs, Candida and St. mutans levels and lactobacilli activity. Candidosis patients exhibited higher Candida CFU values and increased activity of the peroxidase system (p < 0.05) whereas unsaturated iron binding capacity was significantly lower as compared to healthy subjects (p < 0.05). Furthermore, TMLI and Candida CFU values were higher in diseased subjects wearing complete prosthesis as compared to those without complete prosthesis. Diseased subjects with < 1.2 ml/min salivary flow rate exhibited even greater differences with control. This subgroup exhibited a marked reduction in IgAs. The serum components assayed were iron bound protein, unsaturated iron binding capacity, IgG, IgA and IgM. Unsaturated iron binding capacity was significantly lower in the Candidosis group (p = 0.03). Subjects suffering from oral Candidosis display deficiencies in some of their saliva components, evidencing impaired oral defense capacity.

[Effects of local treatment with sodium fluoride mouthrinse on peroxidase and hypothiocyanite saliva levels in adolescent]/. / Efectos del tratamiento local con enjuagatorios de fluoruro de sodio sobre los niveles de peroxidasa e hipotiocianito salivales en adolescentes.

The present work describes and analyzes the results of a randomized clinical trial on adolescents (age 18.2 +/- 0.6) carried out in order to evaluate the effects of a twice daily mouthrinse application containing xylitol, sorbitol, sacarine, ciclamate, aspartame, chlorhexidine, hexetidine or NaF for 14 days on amylase, peroxidase, thiocyanate, hypothiocyanite, secretory IgA and total proteins in whole saliva. No significative changes were observed in health and bucodental parameters nor in flow salivary rate, protein, secretory Ig A, or thiocyanate levels as a consequence of the mouthrinses application. On the other hand, NaF treatment (0.02%, 0.05% or 0.1%) did cause an increase in salivary peroxidase and hypothiocyanite, being the former increase higher than the second one. Peroxidase increase was proportional to the mouthrinse dose (r = 0.78; p < 0.01), but not to the hypothiocyanite increase (r = 0.407; p = 0.12). Since the adolescents' health condition was the adequate, it is suggested that the peroxidase increase was due to a higher enzyme synthesis and/or secretion by the parotid and/or submaxillar glands. It is concluded that the increases in salivary peroxidase and hypothiocyanite caused by the NaF treatment favour the host, as they potentiate one of the mechanisms that modulate dental plaque composition, preventing in such a way the colonization by cariogenic pathogens.

Efectos del tratamiento local con enjuagatorios de fluoruro de sodio sobre los niveles de peroxidasa e hipotiocianito salivales en adolescentes / Effects of local treatment with sodium fluoride mouthrinse on peroxidase and hypothiocyanite saliva levels in adolescents

Se describen y analizan los resultados de un ensayo clínico controlado realizado en adolescentes de ambos sexos (edad 18,2+0,6 años) para evaluar los efectos de dos aplicaciones diarias de enjuagatorios a base de xilitol, sorbitol, sacarina, ciclamato, aspartamo, clorhexidina, hexetidina o NaF, durante 14 dÝas, sobre el contenido de amilasa, peroxidase, tiocianato, hipotiocianito, IgA secretoria y proteínas totales de la saliva completa. Como consecuencia de la aplicación de los enjuagatorios no se observaron modificaciones significativas en los indicadores de salud e higiene bucodental, ni en la velocidad de flujo, niveles de proteínas totales, IgA secretoria y tiocianato salivales. En cambio, el tratamiento con NaF (0,02 por ciento, 0,05 por ciento y 0,1 por ciento) produjo un aumento de la peroxidasa salival y del hipotiocianito, siendo el primero de dichos efectos de mayor magnitud que el segundo. El incremento de peroxidasa fue proporcional a la dosis del enjuagatorio (r = 0,78; p<0,01), no así el aumento de hipotiocianito (r = 0,407; p = 0,12). Por cuanto el estado de salud gingival de los adolescentes era adecuado, se sugiere que el aumento de peroxidasa se debió a una mayor sÝntesis y/o secreción de la enzima por parte de las glándulas parótidas y/o submaxilares. Se concluye que los aumentos de peroxidase salival y de hipotiocianito producidos por el trtamiento con NaF son fenómenos favorables para el huésped, al potenciar uno de los mecanismos que regulan la composición de la placa dental, y de tal modo prevenir la colonización por gérmenes cariógenos.

Efectos del tratamiento local con enjuagatorios de fluoruro de sodio sobre los niveles de peroxidasa e hipotiocianito salivales en adolescentes / Effects of local treatment with sodium fluoride mouthrinse on peroxidase and hypothiocyanite saliva levels in adolescents

Se describen y analizan los resultados de un ensayo clínico controlado realizado en adolescentes de ambos sexos (edad 18,2+0,6 años) para evaluar los efectos de dos aplicaciones diarias de enjuagatorios a base de xilitol, sorbitol, sacarina, ciclamato, aspartamo, clorhexidina, hexetidina o NaF, durante 14 dYas, sobre el contenido de amilasa, peroxidase, tiocianato, hipotiocianito, IgA secretoria y proteínas totales de la saliva completa. Como consecuencia de la aplicación de los enjuagatorios no se observaron modificaciones significativas en los indicadores de salud e higiene bucodental, ni en la velocidad de flujo, niveles de proteínas totales, IgA secretoria y tiocianato salivales. En cambio, el tratamiento con NaF (0,02 por ciento, 0,05 por ciento y 0,1 por ciento) produjo un aumento de la peroxidasa salival y del hipotiocianito, siendo el primero de dichos efectos de mayor magnitud que el segundo. El incremento de peroxidasa fue proporcional a la dosis del enjuagatorio (r = 0,78; p<0,01), no así el aumento de hipotiocianito (r = 0,407; p = 0,12). Por cuanto el estado de salud gingival de los adolescentes era adecuado, se sugiere que el aumento de peroxidasa se debió a una mayor sYntesis y/o secreción de la enzima por parte de las glándulas parótidas y/o submaxilares. Se concluye que los aumentos de peroxidase salival y de hipotiocianito producidos por el trtamiento con NaF son fenómenos favorables para el huésped, al potenciar uno de los mecanismos que regulan la composición de la placa dental, y de tal modo prevenir la colonización por gérmenes cariógenos. (AU)

Bucodental health condition in patients with Down syndrome of Cordoba City, Argentina.

The oral health condition of children and youngsters with Down Syndrome (DS) was evaluated on a sample of 86 mongolic subjects ages 3 to 19, both sexes, residents in the city of Córdoba (Argentina), and compared with control groups. Those persons were attended special educational institutions for the care of that type of disabled individuals. In every age group, the dmf-t and dmf-s indexes were higher in the mongolic children than in the control population, while from the age of 10 onwards the DMF-T and DMF-S of the control population were higher than those of the DS individuals. In spite of this, the scarce participation of the DF component in the mentally disabled showed deficiencies in their dental care. This population exhibited a high frequency of retarded eruption, agenesis, conoidism, Angle's type III malocclusion, posterior cross bite and deficient gingival health. A positive correlation was found between tha activity of Lactobacillus and the amount of Streptococcus and the caries indicators. A high concentration of calcium and secretory IgA was found in the group of mongolic subjects. Our analysis evidences that DS patients are at a disadvantage in relation with healthy individuals in terms of oral health. An early program of preventive measures is proposed (dental hygiene, anti-plaque agents, Therapy of Orofacial Regulation) which would involve the education of parents and teachers.

[Dental health status of students living in places supplied with drinking water of very high and very low levels of fluorides]. / Estado de salud bucodental de escolares residentes en localidades abastecidas con agua de consumo humano de muy alto y muy bajo contenido de fluoruros.

The results of a cross sectional epidemiological survey for the purpose of evaluating the state of dental health of schoolchildren (aged 6-7 and 12-13) living in Sampacho and Porteña, two towns in the Province of Córdoba (Argentina), supplied with drinking water containing quite different levels of fluoride, are described and analized. In Sampacho, F- level is 9.05 mg/l. while in Porteña the concentration is of 0.19 mg/l. The proportion of schoolchildren (aged 6-7 and 12-13) without caries was significaticantly higher in Sampacho than in Porteña, while the dmf-t, dmf-s, DMF-T and DMF-S indexes were considerably higher in the latter place. The severity of caries in children (age 12-13) living in Sampacho ranged from low to moderate (DMF-T = 2.53), whilst in Porteña the range went from moderate to high (DMF-T = 4.41). No cases of dental fluorosis were recorded in Porteña; but in Sampacho, there was a high proportion of children with mild fluorosis (aged 6-7) and mild or severe fluorosis (aged 12-13). Calcium, phosphate, thiocyanate, protein and secretory Ig A salivary levels were similar not only among schoolchildren of both towns but also among those with different experience of caries and different degrees of severity of fluorosis. It is concluded that urgent (preventive and/or curative) sanitary measures are necessary for the purpose of reducing or controlling caries in Porteña as well as dental fluorosis in Sampacho.

[Dental caries distribution in preschool children in an urban area of Argentina, 1992]. / Distribución de la caries dental en niños preescolares en una región urbana, Argentina, 1992.

An investigation undertaken into a sample of 1,115 five-year old children attending kindergartens in the city of Córdoba (Argentina) is described. The investigation aimed at establishing the prevalence and distribution of dental caries by socioeconomic level. Research showed that the prevalence of caries had decreased 55.0% in relation to the 1973 figure, while the proportion of children with healthy teeth was 26.7% greater. The frequency and seriousness of the caries increased as the child's social position declined. At the highest socioeconomic level NES I = entrepreneurial and managerial bourgeoisie), the rates of caries were significantly lower than those at the lowest socioeconomic level (NES III = typical proletariat, nontypical proletariat and sub-proletariat) presenting dmf-t of 0.8 and 2.7, and dmf-s of 0.9 and 4.9, respectively. In NES III, the dmf-t main components were decayed and missing teeth, while in NES I filled teeth were the main components. The proportion of children with no experience of caries was 63.1% in NES I and 11.5% in NES III. Inversly, the rate dental health was higher in NES I (8.8) than in NES III (5.1). The cost per child required for the restorative treatment in approximately two and a half times greater in NES III than in NES I. Considering the sample as a whole the expenditure required for NES III would be more than ten times higher than that required for NES I.(ABSTRACT TRUNCATED AT 250 WORDS)

[Information level and pharmacotherapeutic practice of dentists, 1990]. / Nivel de información y conducta farmacoterapéutica de los odontólogos, 1990.

Results of an investigation carried out into a population of 285 dentists in Cordoba City (Cordoba, Argentine) with a view to evaluating their pharmacological knowledge, prescriptive behaviour and proposals for the improvement of drug usage, are described. This study showed that 58.3% of the dentists surveyed get most of their pharmacological and therapeutic information through published material issued by pharmacochemical labs. At the same time, about one-third of the individuals surveyed either did not answer or gave incorrect answers to questions related to the pharmacotherapeutic effects the antimicrobial or anti-inflammatory analgesics of their preference. Although 63.5% of the dentists said that they had taken the essential drug model reference list issued by the social security system into account, many of the drugs selected as preferences were not to be found on it. Regarding anti-microbial or anti-inflammatory analgesic drugs, the brands most frequently prescribed were the more expensive ones, strong 66.5% of the dentists surveyed stated the contrary. Finally, this investigation revealed that five manufacturers together held a concentration of the anti-microbial and anti-inflammatory analgesics prescribed by 83.7% and 82.4% of the dentists consulted respectively.

[Prevalence of dental caries in elementary school children from a metropolitan area of the province of Córdoba, Argentina]. / Prevalencia de la caries dental en escolares de nivel primario de una región metropolitana de la Provincia de Córdoba, Argentina.

The results of a dental health epidemiologic study in primary school-children (aged 6-12) attending both public (municipal and provincial) and private schools in the city of Cordoba are described. The incidence of deciduous teeth caries was from moderate to high among the 6-year-old school-children from municipal schools but it was low in the provincial and private schools (dmf-t = 4.44, 2.31 and 1.27 respectively). Among both provincial and municipal school-children the most significant component corresponded to teeth with caries and diagnosed extraction, whereas in private school-children it corresponded to filled teeth. The absence of active caries in children was 13.6% in municipal schools, 52.2% in provincial schools and 76.9% in private schools. In 12-year-old school-children, the prevalence of caries in permanent teeth was at the same low level in all schools with a DMF-T ranging from 1.85 (municipal) to 2.59 (private). In general, the need for dental treatment was considerable in all schools. It is concluded that the dental health levels achieved by municipal and provincial schools at the age of 12 must be attributed mainly to preventive measures; should children be assisted earlier, the results would be enhanced.

Hepatic glycogen depletion in fed female rats induced by piroxicam.

The effects of i.p. piroxicam administration on hepatic glycogen levels and enzymatic activities of key enzymes involved into glycogen metabolism in fed female rats were studied. Liver glycogen concentrations in treated rats decreased with increasing time of treatment and doses of piroxicam administered. The fall in glycogen caused by piroxicam persisted for several days after it was discontinued. Neither nadolol nor phenobarbital administration were able to prevent the depleting effect of piroxicam. In the treated rats, glucose-6-phosphatase, glycogen phosphorylase and glycogen synthase activities remained unchanged respect to control. Also, proportion of phosphorylase in the active (a) form was not significantly affected by successive piroxicam daily doses. In contrast, we demonstrated a decrease in the glycogen synthase in the active I form. This reduction was time-dependent on piroxicam treatment. Further, glucose loads were not capable to restore activity in the synthase enzyme and liver glycogen synthesis in animals treated with piroxicam. The impairment into glycogen metabolism produced by piroxicam administration suggests liver becomes unable to maintain glucose homeostasis. Furthermore, glycogen depletion might produce an impairment in the metabolism of drugs administered simultaneously with piroxicam, because biotransformation of xenobiotics is a process depending on glycogen storage in the liver cells.

Hepatic glycogen depletion in fed female rats induced by piroxicam.

The effects of i.p. piroxicam administration on hepatic glycogen levels and enzymatic activities of key enzymes involved into glycogen metabolism in fed female rats were studied. Liver glycogen concentrations in treated rats decreased with increasing time of treatment and doses of piroxicam administered. The fall in glycogen caused by piroxicam persisted for several days after it was discontinued. Neither nadolol nor phenobarbital administration were able to prevent the depleting effect of piroxicam. In the treated rats, glucose-6-phosphatase, glycogen phosphorylase and glycogen synthase activities remained unchanged respect to control. Also, proportion of phosphorylase in the active (a) form was not significantly affected by successive piroxicam daily doses. In contrast, we demonstrated a decrease in the glycogen synthase in the active I form. This reduction was time-dependent on piroxicam treatment. Further, glucose loads were not capable to restore activity in the synthase enzyme and liver glycogen synthesis in animals treated with piroxicam. The impairment into glycogen metabolism produced by piroxicam administration suggests liver becomes unable to maintain glucose homeostasis. Furthermore, glycogen depletion might produce an impairment in the metabolism of drugs administered simultaneously with piroxicam, because biotransformation of xenobiotics is a process depending on glycogen storage in the liver cells.

Hepatic glycogen depletion in fed female rats induced by piroxicam.

The effects of i.p. piroxicam administration on hepatic glycogen levels and enzymatic activities of key enzymes involved into glycogen metabolism in fed female rats were studied. Liver glycogen concentrations in treated rats decreased with increasing time of treatment and doses of piroxicam administered. The fall in glycogen caused by piroxicam persisted for several days after it was discontinued. Neither nadolol nor phenobarbital administration were able to prevent the depleting effect of piroxicam. In the treated rats, glucose-6-phosphatase, glycogen phosphorylase and glycogen synthase activities remained unchanged respect to control. Also, proportion of phosphorylase in the active (a) form was not significantly affected by successive piroxicam daily doses. In contrast, we demonstrated a decrease in the glycogen synthase in the active I form. This reduction was time-dependent on piroxicam treatment. Further, glucose loads were not capable to restore activity in the synthase enzyme and liver glycogen synthesis in animals treated with piroxicam. The impairment into glycogen metabolism produced by piroxicam administration suggests liver becomes unable to maintain glucose homeostasis. Furthermore, glycogen depletion might produce an impairment in the metabolism of drugs administered simultaneously with piroxicam, because biotransformation of xenobiotics is a process depending on glycogen storage in the liver cells.

Impairment of human antipyrine metabolism by piroxicam.

The pharmacokinetics of a single oral dose of antipyrine was determined in healthy young volunteers (18-28 years), both 3 days before piroxicam, ketoprofen, or naproxen administration and on the following day of their discontinuation. In all subjects treated with piroxicam (10, 20, and 40 mg daily) for 5 consecutive days, the rate of salivary antipyrine elimination slowed. Antipyrine half-life was prolonged and metabolic clearance was reduced significantly (p less than 0.01) proportional to the dose administered. After piroxicam was discontinued, both pharmacokinetic parameters of antipyrine returned toward normal. No significant modification in antipyrine half-life or metabolic clearance rate was demonstrated after pretreatment with ketoprofen (50, 100, and 200 mg daily) or naproxen (250 and 500 mg daily). The impairment on antipyrine disposition produced by piroxicam has been interpreted as a consequence of a reduction in the activity of hepatic microsomal drug-metabolizing enzymes, particularly the cytochrome P-450 system. These results suggest the possibility of drug accumulation and toxicity when certain other therapeutic agents are administered simultaneously with piroxicam. For the same reason, it is recommended to bear in mind the potential danger of long-term piroxicam therapy on the oxidative degradation of steroid hormones and other endogenous compounds that are metabolized by the mixed-function oxidase system.