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J A Banderas

Publications and source records attributed to J A Banderas.

9 recordsLinked to original sources
PubMed1999

Particle-induced X-ray emission and scanning electron microscopic analyses of the effects of CO2 laser irradiation on dentinal structure.

OBJECTIVES: The purpose of this study was to analyze the physico-chemical changes present on the dentinal surface after using CO2 laser irradiation, and to determine whether or not it is possible to seal the dentinal tubules. METHODS: Thirty human-extracted first premolars were obtained for this study. A Class V cavity was prepared on the buccal surface of all the specimens with a carbide pear-shaped bur, using a conventional high speed handpiece. Fifteen premolars (experimental group) were irradiated with a CO2 laser (with a wavelength of 10.6 microm, 2 W, 10 J, 0.2 s, 25 pulses). The remaining 15 premolars were used as the control group. RESULTS: Scanning electron microscopy showed that the effect of laser energy on dentin varied from charring, cratering, poring, fissuring, fracturing and cracking up to melting; also, the dentinal tubules were not sealed, in contrast with the control group in which the dentinal surfaces were more homogeneous. Particle-induced X-ray emission results showed that the irradiated dentinal surface presented a decrease in calcium content and an increase in phosphorous content, possibly due to a vaporization process which occurred during the irradiation. CONCLUSION: The physicochemical changes observed on the irradiated dentinal surface suggest that changes in the hydroxyapatite crystal structure take place, and that these structural changes may be responsible for the observed effects.

Bicuspid↗
PubMed1999

Oral mucosa lesions in Mazahua Indian adolescents.

The epidemiologic data on oral lesions in native Indians remain unknown in many countries around the world. This paper reports the prevalence and distribution of oral congenital anomalies and pathologic lesions found in a survey of 107 schoolchildren (ages 12 to 17), from two isolated communities in the ethnographic Mazahua area in the State of Mexico. The main entities identified were: pigmented lesions (47.6%), lingual anomalies (17.4%) and developmental tooth alterations (6.9%). The remaining 24.4% of the lesions were gingival inflammatory hyperplasia, partial ankilosis of the tongue, lichen planus, focal epithelial hyperplasia and the double lip. The most frequent localization was lips and tongue. These findings suggest the high prevalence of oral anomalies in this Indian population. Therefore, we suggest that health programs should emphasize the prevention, diagnosis and treatment of these pathologies in Indians groups.

Adolescent↗
PubMed1997

Salivary lead and cadmium in a young population residing in Mexico city.

Mexico city has a very high pollution index. Based on the view 'that salivary monitoring can be extended to environmental pollutants', we performed this study in order to determine not only the concentrations of lead and cadmium in human saliva, but also to establish their possible association with some socio-demographic factors. One hundred dental students from the National Autonomous University of Mexico living in Mexico city participated in the study. Stimulated human whole saliva samples were analyzed by atomic absorption spectroscopy. The results show that Pb (x = 3.10 microg/dl(-1); maximum x = 16.8 microg/dl(-1) and minimum x = 0.04 microg/dl[-1]) and Cd (x = 0.25 microg/dl(-1); maximum x = 2.04 microg/dl(-1) and minimum x = 0.004 microg/dl[-1]) concentrations were higher than those reported elsewhere, and that there was no association between several variables studied (age, gender, geographic area and consumption of canned food) and salivary Pb. However, an inverse association was found between Cd and age (chi2 = 5.9012; P < or = 0.05; gamma = -0.5224, P < or = 0.05). From this study it can be concluded that saliva has potential as a technique for monitoring ambient pollutants recent exposure, since circulating levels of certain polluting chemicals can be transported into salivary glands and secretions.

Adult↗
PubMed1993

Sialochemistry: a diagnostic tool?

Saliva has proven to be a discriminating element in forensic arenas, an effective indicator of acute diseases of salivary glands, and a promising probe for drug monitoring. With the advent of sensitive immunochemical assays, the compositional profile of human salivary secretions has been expanded considerably. Thus, the establishment of a range of "normal values" for a variety of "intrinsic" and "extrinsic" salivary components represented the initial step to use saliva as a diagnostic tool of oral health status. Unfortunately, numerous cross-sectional studies have shown a wide individual variation in the salivary composition of healthy populations, thus precluding its use as a diagnostic chair-side test for the screening of the most common chronic oral diseases (e.g. caries and periodontal disease). A possible explanation may arise from the wide functional versatility of salivary molecules. For instance, it has been recognized recently that in addition to its digestive properties, salivary amylase may modulate bacterial colonization, whereas histatins are not only antifungal but also bactericidal. Thus, low levels of already known antimicrobial salivary molecules (e.g., secretory IgA, lactoferrin, and lysozyme) could be compensated with higher concentrations of other molecules with antimicrobial activity, such as amylase and histatins. Consequently, for caries and periodontal diseases, longitudinal sialochemical studies may yield more insight than cross-sectional studies.

Aged↗
PubMed1992

Levels of salivary cystatins in periodontally healthy and diseased older adults.

Cystatins are cysteine protease inhibitors present in a variety of tissues and body fluids, including saliva. One possible function of these molecules may be to modulate tissue destruction in periodontal diseases. To investigate the potential role of salivary cystatins in these events, the levels of cystatins in saliva from periodontally healthy and diseased individuals were measured by enzyme-linked immunosorbent assay. Flow rates and total protein content were determined in all the samples collected, while cysteine protease inhibitory activity was assessed in submandibular-sublingual secretions. Statistical analysis showed no significant differences in the levels and activity of salivary cystatins in periodontally healthy and diseased individuals. These findings suggest that comparing the levels of cystatins in glandular salivas may not be a suitable indicator of periodontal disease status.

Aged↗
PubMed1992

Effects of chronic ethanol consumption on the rat parotid gland.

Two-month-old Wistar rats ingested 10% ethanol for 12 months. Their parotid glands were then compared with those of normal controls by light microscopy. They had extensive ductal and acinar oncocytic transformation; numerous atypical acinar cells showed anisocytosis, polyploidism and hyperchromatism, features that were absent in controls. Oncocytosis and atypical acinar cells have been reported in 2-3-yr-old ('senile') Wistar rats. Thus, chronic alcohol ingestion may produce cellular features resembling those observed in the parotid gland of 'senile' Wistar rats.

Alcoholism↗
PubMedDate not supplied

[Quantification of lead, cadmium and chromium by sialochemistry].

OBJECTIVE: To determine the concentration of lead (Pb), cadmium (Cd), and chromium (Cr) and establish the possible association of these heavy metals with some sociodemographic factors. MATERIAL AND METHODS: A representative sample of one hundred dental students from the National Autonomous University of Mexico living in Mexico City participated in this study. Unstimulated human whole saliva samples were analyzed by Atomic Absorption Spectroscopy. RESULTS: Concentrations of Pb, Cd, and Cr were higher than those reported elsewhere: Pb (X = 3.10 micrograms/dL-1; Maximum: 16.8 micrograms/dL-1 and Minimum: 0.04 microgram/dL-1), Cd (X = 0.25 microgram/dL-1; Maximum: 2.04 micrograms/dL-1 and Minimum: 0.004 microgram/dL-1) and Cr (X = 1.43 micrograms/dL-1; Maximum: 4.82 micrograms/dL-1 and Minimum: 0.05 microgram/dL-1). No association was found between the variables studied (age, sex, geographic area and canned food consumption) with Pb and Cr. However, an inverse association was found between Cd and age (Chi 2 = 5.9012, p < or = 0.05); (gamma = -0.5224, p < or = 0.05). CONCLUSIONS: Salivary monitoring can be used for detection of environmental pollutants (atmospheric or occupational), in addition for detection of drugs, and local and systemic diseases. Heavy metal pollution continues to be a public health problem, and therefore the government should form a program for eliminating pollutants from the environment. Likewise, other studies should be carried out to verify the association between variables such as sex, age, use of glazed ceramics, nutrition, and home address with the concentrations of heavy metals in saliva.

Adult↗