A New Generation of Risk Assessment

Historically, dental hygienists have been instrumental in detecting and managing oral diseases as well as educating patients about prevention and treatment options for dental caries and periodontal diseases, both major causes of tooth loss. The task of preventing new oral diseases—traditionally performed by relying on visual inspection and examination with a sharp explorer, periodontal probe, and radiography—is shifting. Dental caries and periodontal diseases are routinely treated using invasive restorative therapy, scaling and root planing, and surgery. These modalities assume that all patients have the same risk, yet not all patients respond to restorative treatment in the same way. In addition, patient motivation and cooperation with self-care interventions often place the responsibility of prevention on patients, leading to frustrating results when professional recommendations are ignored.

TABLE 1. CARIES RISK FACTORS

• Poor oral hygiene
• Family history
• Sugar exposure
• Orthodontic treatment
• Xerostomia
• General health status
• Carious lesions in past 36 months
• Exposed root surfaces
• White spot lesions, interproximal radiolucencies, and/or frank caries
• Irregular recare interval
• Special health care needs
• Eating disorders
• Tobacco use
• Use of medications that reduce salivary flow
• Drug/alcohol use
• Visible plaque

MEASURING RISK

Risk measures the probability that an event will occur. Oral risk assessment involves identifying an individual’s risk or protective factors that may influence oral health. A risk factor is an environmental, behavioral, or biologic factor that, if present, increases the probability of a disease occurring, and if absent or removed, reduces the probability.¹

Risk assessment involves an evidence based approach toward managing disease. Evidence-based practice uses the best available external evidence from systematic research by converting information needs into answerable questions and locating the best evidence with which to answer the questions and then apply to clinical practice. This approach ensures treatment recommendations are based on a patient’s risk.² Disease risk factors vary among individuals. Diagnosis, prognosis, and treatment options will change depending on the results of risk assessment, which creates a more individualized treatment plan. The results found from the assessment of individual risk factors can help determine treatment options.

MANAGING CARIES RISK

In 2001, the National Institutes of Health (NIH) Consensus Panel on Diagnosis, Treatment, and Management of Dental Caries published the results of a systematic review of the literature on the management of dental caries. The panel concluded that both visual and visual/tactile methods are effective for detecting caries, but that the clinical use of a sharp explorer to detect occlusal caries provides minimal information and can be harmful if it ruptures the surface layer. The panel concluded that dental caries is an infectious disease and must be treated as such, and that the focus should be on prevention. Tooth removal or restoration do not arrest or reverse the caries process.³

The research conducted by the NIH led to a shift in the management of dental disease. The focus moved to the risk factors that cause the disease, assessing these factors, and recommending treatment based on the results of risk assessment. The shift moves oral health care clinicians toward diagnosis, prognosis, and preventive procedures as preferred treatment options.

Caries risk assessment is an evidence-based approach to preventing, reversing, and, when necessary, repairing early damage to teeth using minimally invasive restorative techniques. This model replaces the traditional method of treating dental caries: the restoration of teeth damaged by caries.^4,5

TABLE 2. INTERVENTIONS FOR PATIENTS AT MODERATE TO HIGH RISK OF DENTAL CARIES.

• Sugar-free chewing gum
• Xylitol/sorbitol products such as lozenges and mints
• Antibacterial agents such as chlorhexidine or iodine mouthrinses
• Calcium phosphate-based products for sensitivity (arginine and calcium carbonate)
• pH neutralizing products such as sodium bicarbonate, casein phosphopeptide-amorphous calcium phosphate, amorphous calcium phosphate, and calcium sodium phosphosilicate products
• Fluoridated drinking water, dentifrices, mouthrinses, topical fluoride varnish, and high-concentration fluoride gels and toothpastes
• Resin-based and glass ionomer sealants

CARIES RISK FACTORS

Caries risk factors contribute to existing or future carious lesions (Table 1). Several research groups have developed protocols and forms that can help the practitioner determine the level of risk. Caries risk assessment forms are available through the American Dental Association,⁶ which evaluates risk by asking patients questions related to oral and general health, diet, and habits.

A new approach for caries prevention is caries management by risk assessment (CAMBRA), an evidence-based strategy of prevention and restoration for early carious lesions.⁷ CAMBRA is based on performing a risk assessment on patients at risk of caries and then making individualized recommendations based on the level of risk. The approach is designed is to educate and motivate patients to change their behaviors and implement changes to reach oral health and then maintain it.⁸ For more information on the implementation of CAMBRA, read “Caries Management for the Whole Family” from the February 2009 issue of Dimensions available in the journal’s online issue archive.⁷

Based on risk factors for caries, oral health practitioners may perform tests for oral bacteria levels and saliva flow, and take radiographs that have good contrast and diagnostic quality in order to determine that the lesion has not penetrated the dentinoenamel junction.

INTERVENTION

An evaluation of caries risk factors determines treatment recommendations. Table 2 provides a list of possible interventions for patients at moderate to high risk. Patients at low risk of caries development should receive recommendations for at-home preventive products, regular recare intervals, and in-office fluoride application if water fluoride levels are below 0.6 ppm in their area, in order to keep risk levels low.⁹

TABLE 3. INTERNATIONAL CARIES DETECTION AND ASSESSMENT SYSTEM CODE DESCRIPTIONS.

0 Sound tooth surface, no change after 5-second air drying.
1 First visual change in enamel (seen only after prolonged air drying or restricted to within the confines of a pit or fissure).
2 Distinct visual change in enamel.
3 Localized enamel breakdown (without clinical visual signs of dentinal involvement).
4 Underlying dark shadow from dentin.
5 Distinct cavity with visible dentin.
6 Extensive distinct cavity with visible dentin.

CARIES IDENTIFICATION

The International Caries Detection and Assessment System (ICDAS) detection codes for coronal caries range from 0 to 6 depending on the severity of the lesion. There are minor variations between the visual signs associated with each code depending on a number of factors, including the surface characteristics (pits and fissures versus free smooth surfaces), whether there are adjacent teeth present (mesial and distal surfaces), and if the caries is associated with a restoration or sealant. Table 3 provides a detailed description of each of the codes. The codes are used for each of the following groups: pits and fissures; smooth surfaces (mesial or distal); free smooth surfaces; and caries associated with restorations and sealants.¹⁰

Treatment options, such as sealants or minimally invasive restorations, may be determined based on the appearance of pits and fissures after air-drying in conjunction with laser fluorescence technology. Laser fluorescence technology used in devices such as DIAGNOdent® (KaVo Dental) and Spectra™ Intraoral Camera (Air Techniques Inc), can be of assistance in estimating occlusal decay.¹¹ Other technologies used in caries detection include LED fluorescence found in Midwest Caries I.D.™ (DENTSPLY Professional); digital radiography used in LOGICON Caries Detector ™ software (Kodak Dental Systems); measuring the bacteria load in the oral cavity as used by CariScreen (Oral BioTech); and fiber optic transillumination used in Microlux™ Transilluminator (AdDent Inc).

PERIODONTAL RISK ASSESSMENT

Risk assessment is a necessary part of the periodontitis treatment paradigm. The American Academy of Periodontology (AAP) asserts that risk assessment should be part of every comprehensive dental and periodontal evaluation. The AAP states: “Risk assessment goes beyond the identification of the existence of disease and severity, and considers factors that may influence future disease progression.”¹² Identifying adverse changes in risk factors is an important concept.¹² Table 4 lists the risk factors associated with periodontal diseases.

Dental hygienists are at the forefront of periodontal risk assessment because they are looking for symptoms of disease. However, assessing patients’ risk levels before symptoms appear may contribute to improved outcomes. Many tools have been developed to help clinicians assess risk before symptoms become apparent.

In 2003, PreViser Corp developed the Pre-Viser RiskCalulator™ as a diagnostic tool to help manage periodontal risk. It is a computer information system engineered to analyze an individual’s risk of periodontal disease and assess his or her current disease state based on information collected during clinical examination and from answers to specific questions concerning risk factors for periodontal diseases.

Patients receive a score that incorporates their risk factors and medical histories. PreViser helps clinicians tailor treatment to an individual’s specific needs rather than treating all patients the same. Patients can see what the expected outcome of treatment will be with respect to their current disease and risk of future disease.¹³

TABLE 4. RISK FACTORS FOR PERIODONTAL DISEASES.

• Cigarette smoking
• Diabetes
• Poor oral hygiene
• Periodontal pockets
• Vertical bone lesions
• Furcation involvements
• Subgingival calculus
• Restorations with subgingival margins

Patients can now calculate their own risk of periodontal diseases through tools provided by the AAP at: www.perio.org/consumer/4a.htmla and PreViser’s web-based tool: www.mydentalscore.com.

Other periodontal disease assessment tools are also available. Oral DNA® Labs makes a genetic test, My PerioID® PST®, designed to identify patients who may be at risk of severe periodontal infections. The test uses genetic information taken from a mouthrinse sample to identify susceptibility to periodontitis. Hain Diagnostics makes a biologic test called micro-IDent™ that provides analysis of the pathogens present in the oral cavity, including quality, quantity, and information about the communities of 11 different periopathogens. These data are then used to create an individualized treatment plan.

CONCLUSION

The identification of risk factors has contributed greatly to our understanding of oral diseases, leading to new approaches to treatment. Implementing change is often challenging, but new treatment methodologies can help dental hygienists provide patients with a health care strategy based on risk reduction and disease prevention, while minimizing the need for complex therapies. The end result should be improved oral health.¹³

REFERENCES

1. Burt BA. Definitions of risk. J Dent Educ. 2001;65:1007-1008.
2. Evidence-Based Medicine Working Group. Evidence-based medicine. A new approach to teaching the practice of medicine. JAMA. 1992;268:2420-2425.
3. NIH Consensus Development Conference on Diagnosis and Management of Dental Caries Throughout Life. Bethesda, MD, March 26-28, 2001. Conference Papers. J Dent Educ. 2001;65:935-1179.
4. Young DA, Featherstone JD, Roth JR, et al. Caries management by risk assessment: implementation guidelines. J Calif Dent Assoc. 2007;35:799-805.
5. Young DA, Featherstone JD, Roth JR. Curing the silent epidemic: caries management in the 21st century and beyond. J Calif Dent Assoc. 2007;35(10):681-685
6. ADA Caries Risk Assessment Forms. Available at: www.ada.org/2752.aspx?currentTab=2. Accessed December 27, 2010.
7. Francisco EM, Azevedo S, Lyon LJ, Johnson Horlak E, Watson P, Young DA. Managing the risk of caries. Dimensions of Dental Hygiene. 2008;6(10):40-45.
8. Kutsch VK, Milicich G, Domb W, Anderson M, Zinman E. How to integrate CAMBRA into private practice. J Calif Dent Assoc.200735:778-785.
9. Young DA, Featherstone JD. Implementing caries risk assessment and clinical intervention. Dent Clin N Am. 2010;54:495-505.
10. Pitts N. “ICDAS”—an international system for caries detection and assessment being developed to facilitate caries epidemiology, research and appropriate clinical management. Community Dent Health. 2004;21:193-198.
11. Bader JD, Shugars DA. A systematic review of the performance of a laser fluorescence device for detecting caries. J Am Dent Assoc. 2004;135:1413-1426.
12. American Academy of Periodontology. American Academy of Periodontology statement on risk assessment. J Periodontol. 2008;79:202.
13. Page RC, Martin JA, Loeb CF. The Oral Health Information Suite (OHIS): Its use in the management of periodontal disease. J Dent Educ. 2005;69:509-520.

From Dimensions of Dental Hygiene. January 2011; 9(1): 50, 52-53.