|Year : 2010 | Volume
| Issue : 4 | Page : 278-281
A study of influence of sugars on the modulations of dental plaque pH in children with rampant caries, moderate caries and no caries
D Utreja1, A Tewari2, HS Chawla2
1 Professor and HOD, Department of Pediatric Dentistry, BRS Dental College, Panchkula, India
2 Ex- Professor and Head, Department of Oral Sciences, Post Graduate Institute of Medical Education and Research, Chandigarh, India
|Date of Web Publication||25-Jan-2011|
Department of Pediatric Dentistry, BRS Dental College, Panchkula
| Abstract|| |
The present study is undertaken to find out the pH of resting plaque in children with no caries, moderate caries and rampant caries and to determine the modulations of plaque pH with different sugar solution rinses viz: sucrose, glucose and fructose. The study was carried out on forty five children, in the age group of 3-10 years (25 males and 20 females). The child was given 10 ml of test solution and was asked to rinse and swish it in the mouth for a period of 30 sec. Plaque samples were taken from 20 different spots after 5, 10, 20 and 30 min of the rinse and pH values of all the samples were determined. Results show that there was a statistically significant (P<0.05) difference between the pH values of plaque at different intervals of time with sucrose, fructose and glucose solution rinse in children with moderate caries, rampant caries as compared to the caries free group. Sucrose was found to be highly cariogenic in all the children with a greater potentiating effect in moderate and rampant caries. Glucose also appeared to have a cariogenic role while fructose had the least of it all.
Keywords: Caries, fructose, glucose, pH, sucrose
|How to cite this article:|
Utreja D, Tewari A, Chawla H S. A study of influence of sugars on the modulations of dental plaque pH in children with rampant caries, moderate caries and no caries. J Indian Soc Pedod Prev Dent 2010;28:278-81
|How to cite this URL:|
Utreja D, Tewari A, Chawla H S. A study of influence of sugars on the modulations of dental plaque pH in children with rampant caries, moderate caries and no caries. J Indian Soc Pedod Prev Dent [serial online] 2010 [cited 2013 Jun 19];28:278-81. Available from: http://www.jisppd.com/text.asp?2010/28/4/278/76158
| Introduction|| |
The plurality of factors involved and the otherwise durable nature of tissues invaded make dental caries one of the most unusual diseases which once established is perpetual and does not confer immunity. It involves all population groups in the world with divergent intensity from caries free, moderate caries to rampant caries. ,
The exact etiology of dental caries remains controversial till present time but there is a general agreement that it requires the presence of dental plaque, which is a concentrated aggregation of micro-organisms, muco-polysacchrides and a number of other components making it a very complex and dynamic structure. The micro-organisms by their enzymatic action on carbohydrates produce acids which in turn demineralize the enamel. The acid producing capacity of dental plaque is a proven factor for the initiation of dental caries. The plaque pH varies with the intake of different food stuffs which depends on the acid producing potentialities in dental plaque and to some extent their nature.
A number of studies have been undertaken to determine the effects of different foods like starch,  cooked rice and caramel, beverages like cola, lemonade, apple juice  and sugar solutions  in different concentrations on pH of plaque in cases with moderate to extensive caries. A very few investigations have been carried out to compare the influence of different sugar solutions on plaque pH in caries free, moderate caries and rampant caries. 
The present study is undertaken to find out the pH of resting plaque in children with no caries, moderate caries and rampant caries and to determine the modulations of plaque pH with different sugar solution rinses viz: sucrose, glucose and fructose in children mentioned above.
Sucrose has been considered to be the most cariogenic among all the fermentable carbohydrates. Children consume a large amount of sweets such as candies, jams and sweet beverages containing sucrose or glucose with and in between meals. These can lower the pH of plaque for a quiet longer time interval as they yield 20-30% of fermentable carbohydrates and are acidic in nature. 
Thus it becomes important to study the cariogenicity of these foods as it might help in assessing their cariogenicity and thereby helping in planning a low cariogenic diet schedule for a child.
| Materials and Methods|| |
The study was carried out on forty five children, in the age group of 3-10 years (25 males and 20 females). The sample was randomly selected from the children attending the Pedodontic and Preventive clinic but was stratified according to age, sex and previous caries experience according to the following criteria.
On the first day, each child was given prophylaxis in the form of scaling and polishing and was instructed as follows:
- To follow no oral hygiene regime for the next two days.
- To report back in the preventive laboratory in the early forenoon after two days without taking anything except tap water on the day of reporting.
On this day of examination, the child was made to sit in a chair in a relaxed position and was asked to rinse his mouth with water in order to remove any loose debris on the teeth. Dental plaque material was collected from twenty different spots. The area of collection was from the last two teeth in each quadrant, from both the buccal and lingual surfaces, labial and palatal surfaces of upper and lower incisors. All the plaque subsamples were collected within the time of 30 sec.
The plaque material was pooled in 1ml of cold double distilled de-ionized water in the small-sized test beaker. The electrode was dipped immediately into it to the desired level and pH reading was recorded from the scale. The pH meter was already on mains 15 min before starting the experiment. The values read from pH meter scale were directly used as pH of the plaque sample.
The child was then given 10 ml of test solution and was asked to rinse and swish it in the mouth for a period of 30 sec. Plaque samples were taken in the similar way from 20 different spots after 5, 10, 20 and 30 min of the rinse and pH values of all the samples were determined as explained above.
Before recording the pH in each child, the pH meter was calibrated against standard buffers at pH 4 and pH 7 and to avoid any variability it was also rechecked during the experiment. The procedure was performed with 25% sucrose, glucose and fructose solution in five children each in rampant caries, moderate caries and caries free group. The child was brought to 0 plaque level again before discharging that day.
Determination of the error of the method
Identical experiments were performed with one child during the period of six weeks. For each of the experiment, subject rinsed his mouth with 25% sucrose solution for 30 sec. The standard deviations of the pH values and the pH changes at different time intervals were calculated. The standard error of mean was also determined for each time interval.
The data was recorded on MS Excel and statistically analyzed.
| Results|| |
Results of Students' t test show that there was a statistically significant (P<0.05) difference between the pH values of plaque at different intervals of time with sucrose, fructose and glucose solution rinse in children with moderate caries, rampant caries as compared to the caries free group.[Table 1]
| Discussion|| |
Various methods have been used by different investigators to determine the pH of dental plaque.  In the present study, the method used for this purpose was calomel combination type single glass electrode fitted with Beckman pH electrometer which gave better measurement of plaque pH variations as compared to that with antimony electrode used by Stephen,  pH telemetry method employed by Graph,  vacuum coleman potentiometer by Fosdick. 
In pH telemetry method, the size of the electrode tip is invariably larger than that of the microbial colony aggregates which are made to grow on the glass surface instead of enamel surface in situ. The method employed in this study allowed plaque metabolism on the enamel itself and the pH was measured in vitro using the standardized instrument with minimum possible fluctuations of the pointer thereby avoiding any errors associated with the antimony electrode. This study though carried out in vitro gave a pH value of the acid produced in vivo as the fermentation of sugar took place in the oral cavity before the plaque samples were collected. Plaque material was immediately pooled in cold double distilled de-ionozed water after taking out from the mouth so as to prevent further fermentation and formation of acids which could lower the pH of plaque sample. However, the pH recording was done immediately for the same reasons: within 90 sec.
The mean resting plaque pH in children with rampant caries was found to be 6.8, which was statistically significantly lower as compared to caries free group, where it was noted to be 7. Resting plaque pH in children with moderate caries also had a mildly acidic value of 6.9 which was significantly lower as compared to that in caries free group. The acidic tendency in resting plaques in practically all children in rampant caries and moderate caries group, even when no food had been eaten for many hours, showed some uninvestigated and inherent tendency in these children which makes them basically more susceptible to caries as compared to the caries free group. Cadwell and Bibby hypothetically discussed that in these children, the buffering capacity of the saliva by the way of its flow, viscosity, content and quantity may be deficient thus not able to neutralize the acids being formed in the plaque. ,
Glucose solution brought about a minor fall in plaque pH in the caries free group as it fell to 6.9 after 5 min from 7. It remained 6.9 till 10 min interval and went up to 7 after 20 min where it stayed till 30 min of experiment time, thereby reaching the baseline in just 20 min. In moderate caries group, the fall in pH of plaque was greater than that in caries free group. It fell from 6.9 to 6.6 after 5 min and 6.7 after 10 min. There was a tendency toward rise after 20 min when it became 6.8 and persisted at that value throughout the experimental time, unlike in caries free group, it never reached the baseline throughout the experiment.
A considerable fall in plaque pH was noted in rampant caries group as it came down to a level of 5.8 after 5 min, rose to 6 after 20 min and 6.5 after 30 min. In this group also, it never reached the baseline level within the experimental period.
Fructose solution led to a minor fall in plaque pH in caries free group as it was noted to be 6.9 after 5, 10 and 20 min and reached resting value after 30 min. In moderate caries group, the plaque pH after 5 min was lowered to 6.6 which gradually tended to rise till 30 min and was found to be 6.7, 6.8 and 6.8 at 10, 20 and 30 min respectively.
The pH of plaque in rampant caries group was lowered from 6.8 to 6.1 after 5 min interval. It rose to 6.2 and 6.4 at 10 and 20 min and 6.7 at 30 min which was less than the baseline value by 0.1 pH units. Similar findings have been obtained by Klienberg  with moderate caries group where they observed a negligible fall in most of their test subjects. The decrease in the plaque pH in moderate caries group when compared to that in caries free group was found to be statistically significant at all the time intervals. It was also found to be significant when the plaque pH decrease in rampant caries was compared to that in caries free group.
In the caries free group following the sucrose rinse, the plaque pH was lowered from 7 to 6.8 after 5 min and 6.9 after 10 min where it remained till 20 min and rose further to 7 after 30 min. In moderate caries group, it was found to be 6.5 after 5 min where it remained stable till 10 min, after 20 min it rose to 6.6 and became 6.7 after 30 min which was less than the baseline value by 0.2 pH units. The plaque pH was lowered to 5.4 from the resting pH value of 6.8 in rampant caries group. The fall was well below the critical pH after 5 min and remained so till 10 min. It rose to 5.8, still very near the critical pH after 20 min and 6.4 after 30 min. It still was sufficiently below the baseline level. The results agree with those of Englander HR  where such type of the fall with sucrose has been reported in persons with extensive caries and resulted in characteristic Stephen curve. The lowering of plaque pH in moderate caries and rampant caries group with sucrose rinse when compared to that in caries free group was found to be highly significant at all the time intervals.
Sucrose had a significant effect in lowering the pH plaque which was well below the critical pH in rampant caries group, where pH values when plotted against time followed a characteristic Stephen curve and also the fall was sustained for a longer time (the total experimental time of 30 min). Fall in plaque pH in moderate caries with sucrose also followed the Stephen curve pattern.
Second in order of precedence in cariogenic potentiality was glucose followed by fructose. It was contrary to the findings of Geddes DAM  where he found no difference in the quality and quantity of acid formation by plaque bacteria in caries active individuals with sucrose and glucose. The pattern of plaque pH fall with glucose in rampant caries group also resulted in Stephen curve. It was also observed (pH decrease) to stay longer in rampant caries and moderate caries groups while it was not so with fructose in any of the three study groups. The possible cause of sustained effect of sucrose might be because of its greater glycolysis by plaque bacteria and inability to stimulate the salivary flow to wash away acids formed. Sucrose was found to be highly cariogenic in all the children with a greater potentiating effect in moderate and rampant caries. Glucose also appeared to have a cariogenic role while fructose had the least of it all.[Table 1]
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