口腔念珠菌病患者唾液溶菌酶水平的研究

目的：了解唾液溶菌酶水平与口腔念球菌感染的关系。方法：以正常人群作对照，用琼脂糖含菌平板法测量口腔念珠菌病患者混合唾液溶菌酶含量。结果：口腔念球菌感染者唾液溶菌酶含量高于非感染者对照组。     

充填方式对种植义齿固定螺丝孔粘接强度及密封性的影响研究

 目的　研究不同充填方式封闭种植义齿固定螺丝孔对粘接强度及密封性的影响。方法　制作上颌第一前磨牙种植螺丝固位氧化锆冠试件80件，按照粘接前是否喷砂预处理、充填树脂种类、充填深度随机均分为8组，分别置于墨水溶液7 d，万能材料实验机上对螺丝孔内树脂充填体进行推出测试，记录树脂充填体脱粘接时的瞬间载荷，并取出树脂充填体，显微镜下观察记录并比较充填体染色的范围。结果    是否喷砂及树脂种类对粘接强度的影响均具有统计学意义（P < 0.01）；充填体厚度会显著影响粘接断裂载荷大小（P < 0.01），但对粘接强度的影响无统计学意义（P = 0.09）。喷砂后使用3 mm流动树脂充填微渗漏最少，不喷砂使用2 mm膏状树脂微渗漏最严重，是否喷砂、树脂种类及充填体厚度均对微渗漏有显著影响（P < 0.05）。结论    固定螺丝孔表面喷砂处理可增加粘接强度，减少微渗漏。流动树脂封闭种植义齿固定螺丝孔可获得相似的密封性及高于普通膏状树脂的粘接强度。在一定范围内，增加充填体厚度有助于提高固定螺丝孔封闭树脂的咬合承受力并减少微渗漏。     

Effect of age on immunoglobulin A subclass distribution in human parotid saliva

Two subclasses of immunoglobulin A (IgA) antibodies are produced in humans, IgA1 and IgA2, IgA2 being more resistant to digestion by bacterial proteases than IgA1. The amount of IgA in saliva has been shown to vary with age; however, little is known about the correlation between IgA subclass distribution in saliva and age. The purpose of this study was to determine whether differences exist in the levels and ratio of IgA subclasses in parotid saliva of children and adults. Parotid saliva was obtained from healthy children (age range 6-12 years, n = 14) and adults (age range 22-51 years, n = 20) using Schaefer cups. Samples were analyzed for levels of total IgA, IgA1, and IgA2 by ELISA. IgA and IgA1 levels were significantly higher in adults than in children. However, no differences were seen in the ratio of IgA1 and IgA2 in the two groups of subjects. These findings indicate that levels of IgA increase with age, whereas the IgA subclass ratio is established early in life.     

In vitro streptococcal adherence on prosthetic and implant materials. Interactions with physicochemical surface properties

The aim of this study was to evaluate streptococcal adherence to eight currently used prosthetic and implant materials, and enamel samples, after a salivary coating and to investigate the influence of substrata surface free energy (SFE) and its polar and non-polar components, as well as bacterial surface characteristics, on bacterial adherence. Our results indicate a moderate hydrophobic character of saliva-coated surfaces and a pronounced basic character of the polar component of SFE values, except for one substrata. The lowest colonization was observed with enamel samples and the lowest values of adherent bacteria on the different substrata were observed with the hydrophilic bacterial strain. Both the nature of the substrata and the nature of the bacterial strains could have an effect on the extent of bacterial adhesion. When the interrelationship between the number of adherent bacteria and the surface properties of bacteria and substrata were analysed, bacterial adherence correlated with the non-polar component of substrata SFE (r = 0.8, P = 0.02) and with the adhesion to the solvents (r = 0.8, P < 0.0001). These results are consistent with the thermodynamic theory and underline the importance of acid-base characteristics of the cell surface when one is studying bacterial adherence on dental casting alloys and implant materials.     

Salivary calprotectin levels are raised in patients with oral candidiasis or Sjögren's syndrome but decreased by HIV infection

Calprotectin levels were determined in whole saliva from patients predisposed to oral candidiasis due to HIV infection or Sj?gren's syndrome and from patients with candidiasis associated with various oral disorders (e.g. lichen planus, oral ulceration). Mean calprotectin levels were higher in whole saliva (2 microgram/ml) than in parotid saliva (0.3 microgram/ml). Oral candidiasis was associated with raised whole saliva calprotectin levels in all groups studied. HIV infection was associated with lower levels of salivary calprotectin, in the presence of high or low salivary Candida counts, although CD4+ lymphocyte counts did not significantly correlate with calprotectin concentrations. Calprotectin levels were elevated in saliva from Sj?gren's syndrome patients with oral candidiasis, consistent with mucosal transudation of calprotectin from inflamed mucosa and limited dilution due to decreased salivary flow rates. This study indicates that oral candidiasis is associated with raised calprotectin levels secondary to mucosal inflammation, but that diminution of this candidacidal factor due to HIV infection may be a predisposing factor in the aetiology of oral candidiasis.     

A comparison between different methods for prediction of caries activity

Abstract— The aim of the study was to find out if any of the following factors, alone or in combination, could be used for prediction of caries activity: salivary) S. mutans , salivary lactobacilli, buffer capacity, saliva secretion rate, salivary p^H, the amount of plaque and the caries freguency. The patient material consisted of 300 children between 9 and 12 years old. The increment of caries after 1 and 2 years was compared with all the above factors registered at baseline. Only the factors caries frequency and S. mutans showed a significant correlation to caries activity. In one of the tests the lactobacillus count approached significance. The combination of high numbers of incipient smooth surface lesions, S. mutans and lactobacilli gave a mean value of caries activity almost three times that of the whole group (8.4 versus 3. I).     

人口腔寄生性原虫调查

1986年9～12月对合肥地区口腔科门诊病人572人及健康者120人,进行了口腔寄生性原虫感染的调查。门诊患者口腔原虫总感染率为45.9(±2.0)%(263/572),其中单纯齿龈内阿米巴(简称 Eg)感染率37.1%(212/572);单纯口腔毛滴虫(简称 Tt)感染率5.1%(29/572),混合感染率3.8%(22/572)。Eg 感染率女性显著高于男性。对照组Eg 阳性率为17.5%(21/120),Tt 阴性。矛周病、冠周炎患者 Eg 感染度重者占多数、龋齿患者 Tt 阳性率高者占多数。口腔原虫感染与年龄、涎液 pH、牙膏类型无关。Eg 的感染率与职业无关,与口腔卫生有关。服务员、学生、家属、工人 Tt 感染率相对高于其他职业。检测涎液 pH457例,闽值介于5.0～8.5之间。并对 Eg 致病性与感染方式作了初步探讨。     

Interaction between surface protein antigens of Streptococcus mutans and human salivary components

The potential involvement of surface antigens (Ags) I/II and III of Streptococcus mutans in its adherence to salivary pellicle-coated tooth surfaces was investigated. The binding of radiolabelled Ag I/II to hydroxyapatite was increased by pretreating the mineral with human parotid saliva, and binding was maintained in the continuous presence of saliva. Binding of Ag III to hydroxyapatite was inhibited by pretreatment with, or in the presence of, saliva. Various aminohexoses, and also tris, inhibited the binding of Ag I/II. When Ags I/II and III were tested for their ability to bind to salivary components separated by SDS gel electrophoresis, several proteins capable of binding Ag I/II were identified, notably 2 proteins of apparent relative molecular mass 28,000 and 38,000. Analysis of these proteins, isolated by micro-preparative electrophoresis, indicated high proportions of proline, glycine, and glutamic acid, and overall compositions similar to basic proline-rich salivary proteins.     

A rapid method for separation and detection of human salivary amylase isoenzymes by isoelectric focusing in polyacrylamide gel

abstract – Human salivary proteins were separated by isoelectric focusing on polyacrylamide gel in flat beds at 1000 V for 40 min. Amylase activity was detected after immersing the gel in 0.4 M tris-HCl buffer pH 7.4 to equilibrate the pH gradient. The enzyme activity was detected after diffusion into an overlayer of agarose gel containing an insoluble dye-starch polymer (Phadebas®). Both whole human saliva and parotid saliva from 15 different persons contained four amylase components, except in three cases where only three bands were detected. The bands were all focused within a rather narrow pH range (pH 5.4–7.2) and the results were very reproducible.