致龋菌、唾液缓冲能力与婴幼儿龋的相关性研究

目的探讨唾液中变形链球菌、乳酸杆菌和唾液pH值、缓冲能力与婴幼儿龋的关系。方法将178名42～54个月的儿童分为患龋组（患龋牙数≥5）87例和无龋组91人。吐唾法采集非刺激性唾液和嚼蜡法采集刺激性唾液各2ml，用选择性培养的方法检测刺激性唾液中变形链球菌、乳酸杆菌的检出率和计数水平；测定非刺激性及刺激性唾液的pH值和缓冲能力。结果患龋组唾液变形链球菌和乳酸杆菌的检出率分别为96．6％和79．3％，显著高于无龋组的63．7％和27．5％（P〈0．05）；患龋组两种细菌的计数水平比无龋组高近10倍。患龋组和无龋组刺激性唾液的初始pH值和对酸的缓冲能力均显著高于非刺激性唾液（P〈0．001）；患龋组刺激性和非刺激性唾液的初始pH值和缓冲能力均显著低于无龋组（P〈0．05）；无龋组中变形链球菌、乳酸杆菌和唾液pH值、缓冲能力之间无明显的相关性；患龋组刺激性唾液的缓冲能力与变形链球菌的计数水平显著相关（r=0．249，P〈0．05）。结论变形链球菌和乳酸杆菌是婴幼儿龋的重要致病菌；唾液的初始pH值和缓冲能力偏低可能是影响婴幼儿龋的重要因素。     

Effect of saliva composition on experimental root caries

The aim of this study was to determine the effect of saliva composition on caries lesion development independently of the flow rate of unstimulated whole saliva (UWS) and other caries-related variables such as lesion progression time, oral hygiene level, and fluoride exposure. We hypothesized that this could be done by developing experimental root caries under carefully controlled conditions in situ in test subjects with UWS flow rates within a narrow window of normalcy. Fifteen female and 5 male subjects (66 +/- 6 years) were selected for the study according to their UWS flow rates between 0.2 and 0.4 ml/min. All subjects developed experimental root caries lesions during a 62-day period in which UWS as well as stimulated whole saliva (SWS) were repeatedly collected and analysed for flow rate, pH, buffer capacity, inorganic, and organic composition. Caries lesion development was determined by quantitative microradiography. The mean UWS flow rate was 0.30 +/- 0.05 ml/min. Significant negative correlations were obtained between UWS total phosphate concentration and mineral loss (DeltaZ; r(s) = -0.72, p < 0.001) and UWS total protein concentration and DeltaZ (r(s) = -0.70, p < 0.01). SWS and its constituents had only limited or no effect on DeltaZ. Qualitative UWS protein analysis (SDS-PAGE) revealed that subjects with low DeltaZ values had broader and more stained amylase bands than subjects with high DeltaZ values. These findings were confirmed quantitatively by HPLC. We conclude that, within a group of subjects with normal UWS flow rates, the UWS composition was more important for caries lesion development than the SWS composition. Furthermore, high UWS concentrations of phosphate, protein, and amylase were caries-protective.     

胃食管反流病患者唾液腺功能的变化

目的探讨胃食管反流病（gastroesophageal reflux disease,GERD）患者的非刺激性唾液（unstimulated whole saliva,UWS）和刺激性唾液（stimulated whole saliva,SWS）初始pH值、唾液缓冲能力和唾液流率等唾液腺功能的改变。方法收集57例确诊的GERD住院患者和24名健康人的非刺激性唾液、刺激性唾液各2ml,测定唾液的pH值、唾液缓冲能力和唾液流率。结果①GERD组刺激性唾液的初始pH值极显著高于非刺激性唾液（P〈0.001）;②对照组非刺激性唾液的缓冲能力显著高于GERD组非刺激性唾液的缓冲能力（P〈0.01）,对照组刺激性唾液的缓冲能力高于GERD组刺激性唾液的缓冲能力（P〈0.05）;③对照组非刺激性唾液的流率极显著高于GERD组非刺激性唾液的流率（P〈0.001）,对照组刺激性唾液的流率显著高于GERD组刺激性唾液的流率（P〈0.01）。结论GERD患者唾液腺功能降低。     

3～4 岁儿童唾液蛋白含量的研究

目的:探讨3~4岁无龋儿童非刺激性和刺激性唾液中IgA、乳酸脱氢酶、碱性磷酸酶、溶菌酶和总蛋白含量的差异,为研究婴幼儿的唾液成分提供基础数据。方法:采集北京市区94名3~4岁无龋儿童刺激性和非刺激性唾液各2ml,测定唾液中的IgA、乳酸脱氢酶、碱性磷酸酶、溶菌酶和总蛋白的含量。结果:女性非刺激性唾液总蛋白含量显著低于男性(P<0.05);其余各成分在男性和女性唾液中的含量均无显著差异(P>0.05)。刺激性唾液中IgA含量显著低于非刺激性唾液(P<0.01),而乳酸脱氢酶和总蛋白含量显著高于非刺激性唾液(P<0.01);刺激性和非刺激性唾液中,碱性磷酸酶和溶菌酶的含量无显著差异(P>0.05)。结论:3~4岁儿童刺激性和非刺激性唾液中蛋白成分不同,男女间唾液蛋白成分也不完全相同。     

有龋和无龋儿童四种唾液蛋白成分的比较

目的比较3～4岁有龋儿童和无龋儿童非刺激性和刺激性唾液中IgA、乳酸脱氢酶、溶菌酶和碱性磷酸酶含量的差异。方法分别采集98例有龋儿童和94名无龋儿童非刺激性和刺激性唾液，测定上述各成分含量。结果非刺激性和刺激性唾液中IgA、乳酸脱氢酶和溶菌酶含量有龋组均显著高于无龋组（P〈0．01），非刺激性唾液中碱性磷酸酶含量有龋组显著高于无龋组（P〈0．05）；但刺激性唾液中碱性磷酸酶含量两组间差异无统计学意义（P〉0．05）。结论非刺激性和刺激性唾液中IgA、乳酸脱氢酶和溶菌酶升高可能与婴幼儿龋的发生、发展有关。     

A method for determining concentrations of calcium complexes in human parotid saliva by gel filtration

Saliva was collected at two flow rates (approx. 0.15 ml/min, pH 6.6 and 1.5 ml/min, pH 7.4) from one subject. The saliva was gel-filtrated at 37 °C in a column, equilibrated and eluted with a buffer containing Ca²⁺ at a concentration equal to that of saliva. Three peaks containing the Ca complexes were identified as proteins (I), phosphate, citrate, lactate (II) and bicarbonate (III). In the weakly stimulated saliva, the total Ca was 0.61 mmol/l, distributed as Ca²⁺ (45 per cent), bound to proteins (10 per cent), complexes to the inorganic ions (35 per cent) and to the organic acids (10 per cent). For strongly stimulated saliva (total Ca 1.15 mmol/l), the corresponding figures were 43.5, 8.7, 40 and 7.8 per cent respectively. The higher total Ca concentration in the strongly stimulated saliva was recovered mainly as Ca²⁺ and Ca complexed to carbonate.     

Simplified and quantitative saliva buffer capacity test using a hand-held pH meter

PURPOSE: To evaluate and compare saliva buffer capacity using a hand-held pH meter and a commercial buffer strip in patients at risk of caries. METHODS: To obtain stimulated saliva, 109 patients were given a paraffin wax to chew for 5 minutes. After reading the pH value of 0.5 ml of tested saliva using a portable hand-held pH meter (B-212), 10 microl of 0.1N HCl was titrated into the obtained saliva up to a total titration of 160 microl, and then the pH value read each time. The commercial buffer strip (CRT) was also evaluated. The correlation in ranking results (high, medium, low) between the B-212 pH meter and CRT buffer were statistically analyzed by the Bartlett's test (P < 0.001). RESULTS: At the point of 50 microd of titrated HCl, the individual saliva buffer capacities were ranked into one of the following three categories; high (above pH 5.5), medium (pH from 5.5 to 4.5) and low (below pH 4.5). The percentages of the tested patients for the different ranks (high, medium, low) of buffer capacity were 50%, 17% and 33% respectively for the B-212 pH meter, and 56%, 17% and 27% respectively for the CRT. For the CRT buffer, 23 out of 109 cases showed inconclusive color change under the colorimetric test. There was significant correlation between ranking buffer capacity measured by the B-212 pH meter and the CRT buffer (P < 0.001).     

Effects of sucking acidic candy on whole-mouth saliva composition

Limited information is available on the effects of sucking acidic candies on saliva composition and the protective role of saliva in this relation. Therefore the aim of this study was to determine salivary effects of sucking acidic candies in vivo in relation to individual variations in whole-saliva flow rate (WSFR) and buffer capacity (WSbeta). Ten healthy young males (24 +/- 2 years) sucked a rhubarb-flavoured acidic hard-boiled candy with tartaric acid available on the Danish market. The whole saliva was collected into a closed system, regarding CO2, at different times as follows: firstly, unstimulated saliva for 5 min (baseline), secondly stimulated saliva for 4 min upon sucking the candy, and finally post-stimulated saliva for 10 min. Saliva pH was determined on a blood gas analyser and WSbeta was estimated from the saliva bicarbonate concentration obtained by the analyser and by ionic balance calculation. The erosive potential of the candy in saliva was estimated from the saliva pH values and degree of saturation with respect to hydroxyapatite (DS(HAp)). The results showed that saliva pH dropped from 6.5 (baseline) down to 4.5 at the fourth minute of sucking the candy, and returned to pH 6.5 five minutes after stimulation (post-stimulated). DS(HAp) decreased upon sucking the candy and saliva from all subjects became undersaturated with respect to HAp. Significant positive correlations were obtained between pH and WSFR (r(s) = 0.47; p < 0.05) and between pH and WSbeta (r(s) = 0.65; p < 0.01). In relation to WSbeta we found that 70% of the buffer capacity originating from the bicarbonate buffer system upon sucking the candy was exerted as phase buffering. We conclude that sucking this type of acidic candies changes whole-mouth saliva composition so that it may have erosive potential and that high WSFR and WSbeta have protective effects against these salivary changes.     

Salivary cortisol, 17β-estradiol, progesterone, dehydroepiandrosterone, and α-amylase in patients with burning mouth syndrome

Oral Diseases (2012) 18, 613–620 Objective: The aim of this study was to investigate salivary markers related with burning mouth syndrome (BMS). Materials and Methods: Thirty female patients with BMS and twenty female control subjects were included. Unstimulated (UWS) and stimulated whole saliva samples (SWS) were collected, and their flow rates were determined. Salivary levels of cortisol, 17β‐estradiol, progesterone, dehydroepiandrosterone (DHEA), and enzymatic activity of α‐amylase were determined. Salivary transferrin level was measured to determine the level of blood contamination in saliva samples. Results: The levels of all analytes in UWS were significantly correlated with those of SWS. The levels of 17β‐estradiol, progesterone, and DHEA in UWS were significantly correlated with age. Age‐matched comparisons revealed that the patient group had significantly higher levels of cortisol in UWS and of 17β‐estradiol in SWS. When the patients were divided into older (≥60 years) and younger (<60 years) groups, the older group showed a significantly lower level of progesterone in UWS. There were no significant relationships between treatment efficacy and levels of salivary analytes. Conclusions: In conclusion, patients with BMS showed significantly higher levels of cortisol in UWS and of 17β‐estradiol in SWS compared with controls.     

Impact of medications on salivary flow rate in patients with xerostomia: a retrospective study by the Xeromeds Consortium

Clinical Oral Investigations - This study evaluates the impact of systemic medications and polypharmacy on unstimulated (UWS) and chewing-stimulated whole saliva (SWS) flow rates in patients with...     

Simplified method to estimate salivary buffer capacity

A new and simplified method to estimate the salivary buffer capacity was tested. The method, Dentobuff Strip, consists of a pH indicator paper that has been impregnated with acid. A small volume of saliva is added to the strip and after 5 min the color of the strip is compared with a chart. The colors have been chosen to indicate low, medium, or good buffer capacity. The buffer capacity of stimulated saliva samples from 62 subjects was measured with the new method and compared with two commonly used clinical methods, Dentobuff, and an electrometric method. The three methods correlated well, and patients with a low salivary buffer capacity (final pH less than or equal to 4), according to the electrometric method, were readily identified with the new Dentobuff Strip method.     

The composition of unstimulated whole saliva of healthy dental students

The purpose of this study was to determine the unstimulated whole saliva biochemical parameters in healthy dental students of Tehran University of Medical Sciences (TUMS) living in the students' dormitory with a mean age of 22 years. Five ml whole saliva samples were obtained by expectoration. The saliva composition was measured by a spectrophotometer and affiliated kits. The data was analyzed through the student's unpaired t-test using the SPSS program. In the male students (n=50) the mean concentrations of glucose (mmol/l), inorganic phosphate (mmol/l), total protein (mg/ml), magnesium (mmol/l), chloride (mmol/l), and calcium (mmol/l) were 0.75+/-0.44, 1.52+/-0.63, 6.69+/-2.89, 1.27+/-0.45, 27.60+/-11.06, and 2.17+/-0.76, respectively. In the female students (n=50) they were 0.73+/-0.47, 1.58+/-0.63, 7.26+/-3.78, 1.37+/-0.44, 30.42+/-12.74, and 1.87+/-0.78, respectively. There were no significant differences between the whole saliva values in male and female students.     

Oral health condition and saliva flow in southern Chinese with Sjögren's syndrome

Objective : To investigate the oral health condition and saliva flow of southern Chinese patients with Sjögren's syndrome (SS). Method : 51 SS patients (26 primary and 25 secondary cases) and 29 controls took part in this cross‐sectional study. Stimulated whole and parotid saliva flow rates, pH, and buffer capacity, and xerostomia, oral mucosal lesions, oral hygiene status, dental and periodontal conditions, prosthetic status were assessed and compared between groups. Results : Stimulated whole saliva (SWS) flow was reduced in primary and secondary SS cases (p<0.001), pH and buffer capacity were also reduced in the primary SS group (p<0.05). SS patients had a greater prevalence of xerostomia than controls (p<0.001). Primary SS patients had a higher mean DMFT, more missing teeth, and more prostheses than secondary SS cases and controls (p<0.05). SWS flow correlated negatively with the number of filled teeth in both SS groups (p<0.05) and the number of decayed teeth in the primary SS group (p<0.05). Conclusion : Despite good oral hygiene and regular dental checkups, the oral health of southern Chinese with primary SS was significantly compromised compared with secondary SS cases and controls, most probably due to the combined effect of impaired salivary gland function and poorer saliva buffer capacity.     

The buffer capacity of single-site, resting, human dental-plaque fluid

A carbonate equilibration method was used to measure the buffer capacity of resting plaque fluid collected from single buccal or interproximal sites of upper and lower first molars or anterior teeth. The maximum buffer capacity was 26 m-equiv./l at pH 7.1. The buffer contribution from the measured concentrations of phosphate and carbonate was calculated for each sample. These values were compared with the buffering actually measured and with that expected from organic acids, proteins, and amino acids at average values, as taken from reports in the literature. Relative contributions of buffer species at the average pH of the samples (6.86) were: 35 per cent phosphate, 10 per cent carbonate, 10 per cent protein, 10 per cent organic acids, 2 per cent amino acids, 30 per cent unidentified. There were no significant differences in the buffer capacities of samples originating from sites that differ in their accessibility to saliva. Buffering in resting plaque fluid is more than twice that in saliva and did not show differences correlated with the intra-oral location of the samples.     

Saliva flow rate, buffer capacity, and pH of autistic individuals

The objective of the study was to evaluate saliva flow rate, buffer capacity, pH levels, and dental caries experience (DCE) in autistic individuals, comparing the results with a control group (CG). The study was performed on 25 noninstitutionalized autistic boys, divided in two groups. G1 composed of ten children, ages 3–8. G2 composed of 15 adolescents ages 9–13. The CG was composed of 25 healthy boys, randomly selected and also divided in two groups: CG3 composed of 14 children ages 4–8, and CG4 composed of 11 adolescents ages 9–14. Whole saliva was collected under slight suction, and pH and buffer capacity were determined using a digital pHmeter. Buffer capacity was measured by titration using 0.01 N HCl, and the flow rate expressed in ml/min, and the DCE was expressed by decayed, missing, and filled teeth (permanent dentition [DMFT] and primary dentition [dmft]). Data were plotted and submitted to nonparametric (Kruskal–Wallis) and parametric (Student’s t test) statistical tests with a significance level less than 0.05. When comparing G1 and CG3, groups did not differ in flow rate, pH levels, buffer capacity, or DMFT. Groups G2 and CG4 differ significantly in pH (p = 0.007) and pHi = 7.0 (p = 0.001), with lower scores for G2. In autistic individuals aged 3–8 and 9–13, medicated or not, there was no significant statistical difference in flow rate, pH, and buffer capacity. The comparison of DCE among autistic children and CG children with deciduous (dmft) and mixed/permanent decayed, missing, and filled teeth (DMFT) did not show statistical difference (p = 0.743). Data suggest that autistic individuals have neither a higher flow rate nor a better buffer capacity. Similar DCE was observed in both groups studied.     

Influence of teas with fruit aroma and ice teas on pH and buffer capacity of saliva

A number of teas with fruit aroma and ice teas has been tested on erosivity. The teas with a fruit taste have at their drinking temperature (45 degrees C) a pH between 6.2 to 7.4. Even teas with a citron or citrus flavour are neutral. The most acidic tea tested has a mango-peach-taste, but contains no buffer system. After mixing 1 ml of total saliva up to 10 ml tea or by rinsing the oral cavity with tea the pH of oral fluid was hardly lowered (minimum 6.3). In contrast, ice teas are rather acidic (pH < 4) and have a strong buffer capacity. Rinsing the oral cavity with 5 ml ice tea resulted in a decrease of the pH of the oral fluid to 4.1-4.9. However, within 2 minutes the pH in the oral fluid was already increased to 5.9-7.1 and after 5 minutes to 6.3-7.1. In other words, the teas with fruit aroma, based on organic taste components do not have an erosive potential. On the other hand, ice teas decrease the pH of the oral fluid drastically to a level that they become erosive. Therefore, from a dental point of view, teas with only a taste of fruit can be advised to replace drinking of soft drinks, but ice teas not.     

Salivary buffer capacity,pH, and stimulated flow rate of crack cocaine users

Aim: Crack cocaine is the freebase form of cocaine that can be smoked. The use of this drug has been considered a public health problem in many countries. The aim of this study was to assess the stimulated salivary flow rate (SSFR), pH, and the buffer capacity of saliva in crack cocaine users. Methods: Stimulated whole saliva was collected from 54 selected crack cocaine users and 40 non‐users. All samples were analyzed for SSFR, pH, and buffer capacity. SSFR was analyzed by gravimetric method. The buffer capacity and pH were determined using a digital pH meter. Results: The crack cocaine users demonstrated higher buffer capacity than the control group (P > 0.05). Salivary pH was lower in crack cocaine users (P < 0.05). Mean values of the SSFR for the experimental and control groups were 1.1 and 1.3 mL/min, respectively (P > 0.05). Conclusion: Crack cocaine users might exhibit a significant decrease in salivary pH, but not in salivary flow rate or buffer capacity.     

Comparative analysis of CRT Buffer, GC saliva check buffer tests and laboratory titration to evaluate saliva buffering capacity

OBJECTIVE. The purpose of this study is to evaluate the ability of two commercial strip tests and laboratory titration to detect saliva buffer capacity. MATERIALS AND METHODS. Sixty-four patients were examined. Stimulated saliva was collected and buffer capacity was determined with two different chair-side strip tests in addition to immediate transportation to the laboratory to check the buffering ability by titrating with 0.005 M HCl and measuring pH by digital pH/Ion meter, used as a gold standart. The correlation were analyzed using the Spearman Rank Correlation Test, Cohen's Kappa coefficient and Pearson's Correlation test, p < 0.01. Sensitivity and specificity were used to measure precision of these tests. RESULTS. The response rate was 80%. High buffer capacity was found in 23.4% of cases, medium in 62.5%, and low in 14.1%. The Spearman Rank Correlation coefficient between the titration method and CRT Buffer test was 0.685 and the GC Saliva Check Buffer was 0.837. The Kappa coefficient for the CRT Buffer test was 0.508, while the coefficient for the GC Saliva Check Buffer was 0.752. The Pearson Correlation for the GC Saliva Check was 0.675. The difference is found in the buffer capacity at initial pH and at pH value 3. CONCLUSIONS. Both colorimetric tests correlate with the acid titration method in laboratory and are usable for saliva buffer capacity detection in dental offices. Buffer capacity detected in laboratory at different pH values can provide more information regarding caries risk.