Dental Materials Improved for the Prevention of Caries

May 1, 2007
Traditional methods of caries prevention have been to decrease plaque accumulation with a thorough home-care regimen ...

by Anty Lam, RDH, MPH

Traditional methods of caries prevention have been to decrease plaque accumulation with a thorough home-care regimen, recommendations for fluoride exposure, sealant applications, nutritional counseling, and biannual dental examinations. However, the delivery of professional services such as sealant applications and fluorides can be challenging, especially when working with children.

The morphology of the tooth’s pits and fissures on the occlusal surfaces of premolars and molars render them highly vulnerable to tooth decay. Sealant placement is an effective means of preventing tooth pits and fissures caries. Dental sealants have been used for more than 30 years and are approved by the American Dental Association, the National Institutes of Dental and Craniofacial Research, and the American Public Health Association. Sealants act as a physical barrier between the caries-susceptible occlusal pit surfaces and the oral environment, thus preventing the initiation of dental caries. Garcia-Godoy and Harris stated that not all the surfaces of a tooth are susceptible to caries, and 50 percent of the carious lesions occur on the occlusal pits and fissures.1 The reduction of occlusal caries following dental sealant application is highly significant and dependent upon sealant retention. Dental sealants that are applied using appropriate techniques are virtually 100 percent effective in the prevention of tooth decay.2 In 1997, Carlsson and colleagues did a study comparing the caries rates between virgin permanent molars and sealed permanent molars. The result was a 45 percent lower caries rate in sealed permanent molars.3

Sealant retention is a critical factor in gaining the preventive benefit. The most common cause for failure with current sealant materials is moisture contamination by saliva during the application process, which decreases the bond strength of the sealant material to the enamel surface.

Rubber dam placement for sealant application is an excellent way to maintain a dry enamel field, but this technique also has its limitations. Even with a rubber dam, moisture contamination of the etched enamel can occur if the dam rips, the clamp position moves, or saliva seeps up by the bow of the clamp. Additionally, placing a clamp may not be possible on children whose molar anatomy or position in the jaw will not allow the clamp to be in a stable position. Hence, it is necessary to place sealants using the alternative method of isolation: cotton rolls. With cotton roll isolation, the risk of saliva contamination is greater than with a rubber dam. Therefore, both of the currently acceptable isolation techniques have the potential risk of saliva contamination during the application of a sealant. Another challenge in working with young children is maintaining a dry field, especially with children’s curious tongues, hyperactive lips, and exaggerated gag reflexes. Dr. Steven M. Adair, in the March 2003 issue of the Journal of the California Dental Association, recommended that manufacturers develop improved and innovative sealants that would tolerate a moist enamel surface.4 In response to this recommendation, the Pulpdent Corporation and 3M ESPE rose to the challenge.

The Pulpdent Corporation introduced a new product in dental sealant application called Embrace WetBond. Instead of drying the tooth surface to a white, chalky appearance after etching, the tooth surface is lightly dried either with a short blast of air or a cotton pellet, leaving the tooth surface slightly moist with a glossy or shiny appearance. The sealant material is then applied and cured. Dr. Joseph O’Donnell did an independent study on the clinical performance of Embrace WetBond and concluded that the wet-bonding technique had promising effectiveness and could be a reliable choice of pit and fissure sealants for pediatric patients.5 The Embrace WetBond Pit and Fissure Sealant is available in off-white or natural shade, and the product does not require bonding agents.

The 3M ESPE Corporation introduced another technique to increase sealant retention on saliva-contaminated enamel surfaces by using bonding agents. Clinical Guidelines on Pediatric Restorative Dentistry (2005-2006) from the American Academy of Pediatric Dentistry states that a hydrophilic material bonding layer as part of or under the actual sealant could enhance sealant retention and decrease microleakage.6 A product of 3M ESPE, Adper Prompt L-Pop Self-Etch Adhesive, provides a “no-rinse” sealant technique to improve sealant retention on contaminated enamel surfaces. The Self-Etch Adhesive is applied to a cleaned occlusal surface for about 15 seconds, and then dried by a gentle stream of air instead of being rinsed off. After that, a light-cured sealant is applied to the surface and both layers are light-cured simultaneously.

Dr. Perdigao and colleagues did a study to compare the bond strength between Adper Prompt L-Pop Self-Etch Adhesive and the traditional sealant etchant of phosphoric acid. The results indicated that the two dental materials had equivalent bond strengths.7 Peutzfeldt and Nielsen (2004) and Fiegal and Quelhas (2003) also had similar findings that suggested the Adper Prompt L-Pop Self-Etch Adhesive as a preferred material for sealant application in young children because it shortened the treatment time and complexity significantly.8,9

Innovations with fluoride varnish

Dental materials have also improved in the area of fluoride. In-office topical application of fluoride with trays may not be successful for some young patients who have a strong gag reflex or cognitively cannot tolerate the fluoride gel or foam for a full four minutes.

Fluoride varnish is an alternative professional fluoride application for young children as well as developmentally delayed children. If used properly, varnish can reduce caries by 40 to 56 percent.10 The application of fluoride varnish is quick and easy. It is painted on the tooth surfaces, and it sets on contact with saliva. Although most patients accept the procedure readily, their feedback indicated that taste and a temporary color change of the teeth were always a concern.11 The first-generation fluoride varnish products formed a yellowish or brownish film on tooth surfaces when they contacted with saliva.

To increase patient acceptance, the new generation of fluoride varnish such as DENTSPLY’s AllSolution 5 percent Sodium Fluoride Varnish is available. It dries to a tooth-color shade when set and has a pleasant raspberry flavor. Another new product to consider is 5 percent NaF White varnish from Omnii / 3M ESPE. It is a natural tooth color and has cherry and melon flavors. A small-sample study done by the University of Washington Pediatric Dental Clinic in Seattle, Wash., was conducted to determine the perception of this new fluoride varnish. The participants (children ages 4 to 17) received the new fluoride varnish during recall appointments. Both the children and their parents were interviewed after the procedure. Results from this study indicated that esthetics of the white varnish was preferred over the commonly used brownish fluoride varnish.12

Other than the effectiveness and safety of a fluoride varnish product, dental professionals should consider patient preferences in treatment planning to improve compliance. Taste and color were the two most common complaints about first-generation fluoride varnishes. With the improvements in new products, the acceptance of fluoride varnish will certainly increase. Dental professionals should use these innovative products as an alternative to fluoride application with trays. Effective Jan. 2007, the cost of fluoride varnish is covered under the newly added code D1206.13 With this procedure code, the value of dental hygiene services is increased and patients’ access to preventive oral health care is further enhanced.

Dentistry as a profession is always striving to improve the quality of dental care delivered to our patients. Staying abreast of new dental materials helps oral health-care providers improve their care to patients. These innovative dental materials are now available to aid the profession in the prevention of dental caries. The material properties of Pulpdent’s Embrace WetBond and 3M ESPE’s Adper Prompt L-Pop Self-Etch Adhesive will provide a new approach to increase dental sealant retention under a compromised condition and improved management of treatment time. The improvements in the fluoride varnishes of taste and color such as DENTSPLY’s AllSolution Varnish and Omnii / 3M ESPE’s 5 percent NaF White varnish will improve patient compliance because of their appealing flavor and tooth-color shade.

References

1 Garcia-Godoy F, Harris NO, Helm DM. Pit-and-fissure sealants. In: Harris NO, Garcia-Godoy F. Primary Preventive Dentistry. 6th ed. New Jersey: Pearson-Prentice Hall, 2004; 285-318.

2 Diagnosis and management of dental caries throughout life. NIH Consensus Statement Online 2001 March 26-28; [2006,4,20];18(1):1-24.

3 Carlsson A, Petersson M, Twetman S. Two-year clinical performance of a fluoride-containing fissure sealant in young school children at caries risk. Am J Dent June 1997; 10(3):115-119.

4 Adair SM. The role of sealant in caries prevention programs. J Calif Dent Assoc March 2003; 31(3):221-227.

5 O’Donnell JP. A moist environment for sealants: Pediatric office embraces technique for pit and fissure sealing in a wet field. RDH 2006; 26(7):58-60.

6 Guideline on pediatric restorative dentistry. American Academy of Pediatric Dentistry. Reference Manual 2005-2006; 122-129.

7 Pergigao J, Fundingsland JW, Duarte S, Lopes M. Microtensile adhesion of sealants to intact enamel. Int J Pediatr Dent Sept. 2005; 15(5):342-348.

8 Peutzfeldt A, Nielsen LA. Bond strength of a sealant to primary and permanent enamel: phosphoric acid versus self-etching adhesive. Pediatr Dent May/June 2004; 26(3):240-244.

9 Feigal RJ, Quelhas I. Clinical trial of a self-etching adhesive for sealant application: success at 24 months with Prompt L-Pop. Am J Dent Aug. 2003; 16(4):249-251.

10 Vaikuntam J. Fluoride varnishes: should we be using them? Pediatr Dent 2000; 22:513-516.

11 Beltran-Aguilar ED, Goldstein JW, Lockwood SA. Fluoride varnishes: a review of their clinical use, cariostatic mechanism, efficacy and safety. J Am Dent Assoc 2000; 131:589-596.

12 Berg J, Riedy CA, Tercero A. Patient and parental perception of a new fluoride varnish. Compendium Nov. 2006; 27(11):614-619.

13 Cahoon TG. Cracking the code: code changes for 2007-2008. Available at: http://www.adha.org/publications/code.htm. Accessed Dec. 30, 2006.

Anty Lam, RDH, MPH, is an assistant professor in the dental hygiene department at New York City College of Technology, City University of New York. She is a member of the American Dental Educators Association and the American Dental Hygienists’ Association. She practices dental hygiene in a pediatric dental office in New York and can be contacted at [email protected].