RESUMEN
Much research has been devoted to the study of etched enamel, since it is critical to bonding. Currently, there are no precise data regarding the etched-enamel specific surface area. The aim of this study was to characterize, by two different methods, the surface of human dental enamel in vitro after being etched. It was hypothesized that differences would be observed between specimens in terms of specific surface area and grade of etching. Sixteen third molar enamel samples were etched for 30 sec with 37% phosphoric acid prior to being viewed by SEM. Etched enamel surfaces were graded according to the Galil and Wright classification. The total surface area of etched samples was determined by the BET gas absorption method. A substantial variability in total surface area was observed between and among samples. A Pearson's Correlation Coefficient showed a lack of relationship between etch pattern and total surface area.
Asunto(s)
Grabado Ácido Dental , Esmalte Dental/efectos de los fármacos , Adsorción , Humanos , Criptón , Microscopía Electrónica de Rastreo , Tercer Molar , Ácidos Fosfóricos/farmacología , Porosidad , Propiedades de SuperficieRESUMEN
The consequences of xerostomia on oral health have been studied for decades; however, the actual prevalence of this disorder on the general population remains controversial. The purpose of this systematic review was to determine the prevalence of xerostomia in population-based samples. Electronic databases were screened for relevant articles and reference lists of pertinent articles were also hand-searched. Thirteen articles meeting the final inclusion criteria were identified. Based on the definition of xerostomia used in this review, only publications including a subjective diagnosis of the disorder were included. All of the self-reported diagnoses were achieved through a questionnaire either by mail, telephone, interview or self-administered by the patient. There was a variation across papers regarding number and content of the questions as well as guidelines for the diagnosis of xerostomia (i.e. answer yes to one or more than one question). The prevalence of xerostomia in the selected articles ranged from 0.9% to 64.8%. The majority of these studies were performed in Scandinavia. In 9 of the articles, the studied samples were 50 years and older. None of the studies evaluated the prevalence xerostomia among individuals younger than 18 years. Based on these observations, it can be concluded that there is a need for population-based studies on prevalence of xerostomia in regions other than Scandinavia. A standardized protocol to diagnose xerostomia needs to be developed. Patient-perceived treatment needs and impact on quality of life should be included to have a complete picture of public health implications of the disease.
Asunto(s)
Saliva/metabolismo , Xerostomía/epidemiología , Distribución por Edad , Humanos , Prevalencia , Distribución por SexoRESUMEN
Sublethal plasma membrane disruption (PMD) is an established mechanism for signaling in several cell types, including endothelial cells and skeletal muscle. We used a rat model of orthodontic tooth movement to test the hypothesis that periodontal ligament (PDL) cells communicate stretch to changes in bone cell activity in part via PMD. To produce PMD, we used a 50-g load from a spring activated in the buccal direction against the maxillary first molars for 5 min. Uptake of endogenous serum albumin was used as a PMD marker. Immunohistochemistry demonstrates albumin in PDL cells surrounding moved first molar tips. Image analysis shows significantly more albumin in cells of the buccal side (tension) of the moved teeth compared with those of the lingual, distal, and mesial sides, and those of the unmoved control. Albumin localization within cells of the PDL, after only 5 min of mechanical loading, suggests that PMD could promote uptake or release of signaling molecules.