Effects of Carbonated Cola Beverages, Sports and Energy Drinks and Orange Juice on Primary and Permanent Enamel Dissolution

Research Article

Austin J Dent. 2014;1(1): 1004.

Effects of Carbonated Cola Beverages, Sports and Energy Drinks and Orange Juice on Primary and Permanent Enamel Dissolution

Owens BM1*, Mallette JD2 and Phebus JG3

1Department of Restorative Dentistry, University of Tennessee Health Sciences Center, USA

2Private Practices, Pediatric Dentistry, Murfreesboro, USA

3Department of Endodontics, University of Tennessee Health Sciences Center, College of Dentistry

*Corresponding author: Owens BM, Department of Restorative Dentistry, University of Tennessee Health Sciences Center, College of Dentistry, 875 Union Avenue, Memphis, TN 38163, USA

Received: May 28, 2014; Accepted: June 14, 2014; Published: June 17, 2014


The purpose of this in vitro study was to evaluate the effect of carbonated soft drinks, sports and energy beverages, orange juice, and tap water on primary and permanent enamel specimens, measuring mean percentage weight loss.

Beverages used in this study included: Coca-Cola Classic, Diet Coke, Gatorade sports drink, Minute Maid Pure Premium Orange Juice, Red Bull energy drink, and tap water (control). Extracted primary and permanent teeth sectioned into uniform slabs. Twelve primary and 30 permanent enamel specimens were randomly distributed to six beverage groups. The specimens were immersed in each beverage for 24-hour intervals for a 10-day period at 37°C. Specimens were thereafter weighed following each immersion period, with mean percent weight losses calculated per beverage group. The pH and titratable acidity was also determined for each beverage. Enamel weight loss data was subjected to statistical analysis at p<0.05 level of significance.

Primary and permanent enamel specimens immersed in Red Bull and Gatorade showed the greatest mean percent weight loss. Percent weight loss of both primary and permanent specimens showed linear progression with time.

The findings indicate that energy and sports drinks, displayed significantly greater percent mean weight losses of the primary and permanent enamel (dentin) specimens.

These results suggest that intake of these beverages cause enamel dissolution with an accompanying clinical diagnosis of dental erosion. Caution should be exercised in the excessive consumption of these beverages, especially by children and adolescents.

Keywords: Erosion; Soft drinks; Sports drinks; Energy beverages; Ph, Titratable acidity


In the last three decades, the consumption by children and adolescents of "Sugary" or "Sugar-sweetened Beverages" (SSBs) including carbonated "soda" soft drink, sports and energy beverages, fruit drinks, and sweetened bottled waters have increased dramatically [1-7]. Although consumption of carbonated soft drinks has been declining since 2005, U.S. consumers spent a total of $29.0 billion dollars on all SSBs in 2011, with an average consumption of 45 gallons per person per year [8,9].

Since their introduction, consumption of "diet" soft drinks, containing caffeine, artificial sweeteners, and other acidic ingredients have accounted for 29 percent of the soft drink market; however, sales of these drinks have also declined [2]. "Diet" soft drinks were first marketed in the 1980's as low (no) calorie alternatives to "classic" or traditional carbonated cola formulations as "diet" alternatives containing many different flavor choices [10].

So what segment of the population consumes the majority of these beverages? Yes, children and adolescents [11]. At least one SSB is consumed by 66% of children and 77% of adolescent's daily [8]. Including adults and adolescents, males have been found to consume more SSBs than females [3]. Older females consume the lowest (42 calories/day) amount, with the highest consumption rates (70%) by male adolescents, 12-19 years old (273 calories/day) [3]. Furthermore, dietary surveys of adolescents in 1994 indicated that only 29% of boys and 12% of girls consumed the recommended intake of dairy foods. As a result, only 36% of boys and 14% of girls consumed 100% of the Recommended Dietary Allowance (RDA) of calcium, a necessary nutrient for the maintenance of teeth (enamel) and bones [12,13]. In comparison, according to data from 1977- 78, boys and girls consumed 50% more milk than soft drinks as compared to 1994-96 when the beverage consumption levels were reversed [14]. Between 1965 and 1994-96, calcium consumption in children age 11 to 18 decreased from 1,100 mg to 960 mg per day [15]. Thus an increased intake of soft drinks has translated into children and adolescents receiving too little calcium; vitamins A, B and C and magnesium in their diets [16,17]. Consumption of SSBs has also been associated with poor dietary habits, weight gain, obesity, and type 2 diabetes, predominately in adults, but also recognized in children and adolescents [3,5,18-21].

As previously stated, consumption of carbonated soft drinks (sweetened cola's and diet cola's) has decreased, in favor of sports and energy beverages and sweetened waters [5,10]. Sports drinks were originally created as carbohydrate and electrolyte aqueous formulations, to supplement performance and to prevent dehydration during strenuous exercise among.

Athletes [5,7]. From their inception in the 1960's, sports drink consumption has increased significantly, with sales in the U.S. topping $1.5 billion dollars yearly (2008 sales of $7.5 billion); with one report concluding that between 51-62% of adolescents drink at least one sports drink per day [5,22-24]. Consumption trends note that between 2002-2004, among school-age adolescents, the purchase of carbonated soft drinks fell 24% while sports drinks consumption rose by 70% [25]. According to one report [26], "55% of middle school students and 80% of high school students purchased sports drinks (at school).

A second segment of non-traditional beverages marketed to, primarily, the 18-35 age groups include energy or "high-energy" drinks [27]. These beverages, contain stimulants, carbohydrates, amino acids, proteins, vitamins and minerals, and additional acids and other ingredients, with claims of enhancement of physical and mental performance [6,7]. These beverages appeal to younger age groups through anachronistic advertising labels and "hip", new generation slogans, as well as to adults by touting claims of increased short-term energy bursts and increased concentration while at the workplace. According to Beverage World, consumption of energy drinks in the U.S. went from "59.5 million gallons per year in 2003 to 354.5 million gallons in 2009" [28]. Reports in the literature have shown that over 40% of adolescents consume energy drinks and that $3 billion was spent on these beverages in 2008 by adolescents aged 12-24 [29,30]. A correlation between excessive consumption of all the fore-mentioned beverages and the loss of, particularly enamel, following intake, is well established in the dental literature [31,32]. Of particular relevance is the loss of tooth structure through a chemical process of dissolution, whereby extrinsic substances cause irreversible loss of dental hard tissue (enamel and dentin) without the involvement of microorganisms, with a clinical diagnosis of erosion [33,34].

In the oral environment many factors can modify the effect of SSB ingredients on tooth structure, including the chemical properties of the beverage ingredients (pH, titratable acidity, and electrolyte [calcium and phosphate] concentrations); the frequency and method of contact between the enamel surface and the solution; salivary composition, buffering capacity, and flow rate; pellicle formation; enamel type; and individual drinking habits and oral hygiene [35].

The authors recognized that in vitro testing protocols conducted in the present study cannot fully replicate and possibly over-predict in vivo beverage consumption practices and the many factors associated with salivary function. However, the experimental protocol performed (percent weight loss of primary and permanent enamel by select beverages) could be predictive of formal "erosive" processes found in the oral cavity, prior to the execution of further indebt and perhaps more realistic longitudinal, in vivo studies. Consequently, the purpose of this study was to measure the percent weight loss of primary and permanent enamel (and dentin) specimens following immersion in different beverages.

Materials and Methods

Six test beverages (SSBs, fruit juice, and water) were chosen for inclusion into the present study (Table 1). Individual beverages tested were from the same batch as to insure consistency for the testing protocol. Recently extracted maxillary and mandibular primary and permanent human teeth, free of hypo calcification, caries, and macroscopic fractures were carefully cleaned of calculus and other debris. The teeth were previously stored in a 1% Chloramine-T solution (Fisher Chemical, Fair lawn, NJ, USA) consisting of 12% active chlorine diluted in distilled water. The facial or lingual surfaces of all teeth were sectioned into uniform segments (approximately 4.0 mm x 6.0 mm x 1.5 mm) utilizing a high-speed, water-cooled hand piece with a straight fissure carbide bur, and stored in tap water immediately prior to experimentation. It must be noted that it was impossible to isolate only enamel from dentin hard tissues in all of the primary specimens; therefore, all primary teeth contained small remnants of dentin tissue. Primary tooth specimens were divided among five beverage groups and tap water (control) and placed into separate opaque containers, with one specimen per container. Due to the limited availability of sound primary teeth for inclusion in this study, only 12 total specimens could be obtained and sectioned. Permanent enamel test specimens were also randomly distributed to the same beverage groups (and tap water), comprising 5 specimens per group and placed in separate containers, again, with one specimen per container. Prior to specimen immersion, each beverage was tested for: 1) pH (in triplicate) utilizing a pH electrode connected to a Jenco 3601™ (Tenco Instruments Inc., San Diego, CA) analyzer, and 2) titratable acidity (TA) (in triplicate) - titrated to a pH of 8.3 utilizing 1.0 N NaOH. The TA was performed on each beverage by titration of the weight in grams (g) of 1.0 N NaOH required to raise the pH to a level of 8.3.