Particulate bone matrix usage for alveolar bone conservation. A histomorphometric study / Particulate bone matrix usage for alveolar bone conservation. A histomorphometric study.

UNLABELLED: Different filling materials have been used in an attempt to repair bone loss situations. OBJECTIVE: The present study aimed to examine the effect of a bone matrix in post - extraction remodelling of the alveolar bone, and to perform a histomorphometric analysis of the residual alveolar ridges in Wistar rats. MATERIAL AND METHODS: Both rat first lower molars were extracted and the right alveoli were filled with particles of a bone matrix with mineral components (MO - UNC) (experimental group, EG). The left alveoli were used as a control group (CG). The animals were sacrificed at 0 hr., 15, 30 and 60 days after extraction, and the samples were processed. Histological sections were made at the level of the mesial alveolus of the first lower molar. Repair of the alveoli was histologically evaluated and a histomorphometric study of total alveolar volume (TAV), height of the buccal plate (Bh), height of the lingual plate (Lh) and percentage of osseointegration (OI) of the particles was performed to compare the residual ridges of CG with those of the EG. Statistical analysis of the data was performed. RESULTS: In the cases of the experimental group, newly - formed bone tissue was identified around the MO - UNC particles (osseointegration). Histomorphometric data indicate that, at 60 days post - extraction, TAV was significantly greater for EG when compared with CG (p <0.05) and the percentage of osseointegration of the particles increased as a function of time (57.6

, for EG at 15, 30 y 60 days respectively). CONCLUSIONS: The bone matrix (MO - UNC) evaluated in this study is an osteoconductive material that prevents the collapse of post - extraction alveolar bone.

Estudio citomorfométrico de pacientes con cáncer y desórdenes potencialmente malignos de la cavidad bucal / Citomorphometric study of patients with cancer and potentially malignant disorders of the oral cavity

La detección temprana de lesiones bucales promete aumentar sobrevivencia y reducir la morbilidad de los pacientes que sufren esta condición. Un método alternativo para el examen de lesiones en la cavidad bucal, es la citología. Objetivo: valorar las relaciones del tamaño núcleo/citoplasma de células de mucosa bucal sana, de lesiones bucales potencialmente malignas y de cáncer bucal, obtenidas con citología exfoliativa utilizando citomorfometría. Material y método: Se realizó citología a 22 pacientes, de ambos sexos, con edades entre 23 y 81 años utilizando cytobrush. Las muestras se dividieron en tres grupos: 1) citologías de pacientes con lesiones de cáncer bucal (n=7); 2) citologías de pacientes con desórdenes bucales potencialmente malignos (leucoplasia y líquen) (n=15); 3) citologías del lado sano de pacientes con lesiones de cáncer y desórdenes bucales potencialmente malignos (grupo control) (n=15). Se seleccionaron 30 células de cada paciente y se midió el área nuclear (AN), la citoplasmática (AC) y se calculó la relación AN/AN. Se utilizó el Test de Kruskal Wallis y el Sofware estadístico Infostat. Resultados: No se encontraron diferencias significativas entre los tres grupos estudiados al valorar la relación AN/AC. Teniendo en cuenta el género, se observó que en las mujeres se diferenciaron significativamente las células del grupo control de las de los grupos de lesiones. En el género masculino se observaron diferencias significativas entre los tres grupos celulares. No hubo diferencias significativas entre los diferentes grupos etarios .Discusión: A pesar de las diferencias significativas entre los géneros, no es posible hacer una buena separación de los tres grupos de estudio, utilizando solamente citología exfoliativa.

Early detection of bucal lesions promises to increase survival and to reduce morbidity in patients suffering from this condition. An alternative method for examining lesions in the bucal cavity is cytology. Objective: To assess by cytomorphometry the relationship of size nucleus / cytoplasm of superficial cells from healthy bucal mucosa, from potentially malignant bucal disordes lesions and bucal cancer using exfoliative cytology. Material and methods: PAP smear was performed in 22 patients of both gender, aged between 23 and 81. Cytobrush was used. The samples were divided into three study groups: 1) smears of patients with bucal cancer lesions (n = 7), 2) smears of patients with potentially malignant bucal disordes lesions (n = 15), lesions considered were leukoplakia and lichens ; 3) (control group) (n=15): smears of the healthy side of patients with cancer and potentially malignant bucal disordes lesions.Thirty cells were selected for each patient and the nuclear area (NA), cytoplasmic area (CA) were measured and the ratio NA / CA was calculated. We used Kruskal Wallis and Statistical Software InfoStat. Results: No significant differences were found between the three groups studied the relationship NA / CA was assesed . When comparing cells from each of the three groups considering the gender of the patients separately, we found that in women differ significantly from the control group cells and groups of injuries, we could not discriminate between cells obtained from potentially malignant bucal disordes lesions and cancer lesions . In the male gender differences were significant among the three cell groups. Discusion: Despite the significant gender differences, we could not difference the three study groups using only exfoliative cytology.

Effects induced by isoproterenol during synthesis and secretion of the parotid gland: experimental structural studies

The effect of isoproterenol, a â-adrenergic agonist, on the parotid gland of guinea pig was studied in vivo. Male guinea pigs were fasted 12 h, and then injected intraperitoneally with isoproterenol (30 mg/kg). The parotid glands were processed for light and transmission electron microscopy using conventional techniques. Morphological analysis showed massive granular secretion 2 h after isoproterenol injection and an enlarged apical surface of the plasma membrane, as indicated by the presence of microvilli. Twenty-four hours after injection of isoproterenol the gland had still not returned to its pre-stimulation state. The effect of isoproterenol decreased with time and the apical surface of the plasma membrane eventually resumed its normal (basal) appearance. These data showed that the maximum secretagogue effect of isoproterenol on parotid gland of guinea pig was evident 2 h after injection and decreased according to the time.