April 2011, Volume 7, Issue 4
Published by AEGIS Communications
Early Discovery, Assessment, and Diagnosis
Advanced diagnostic technologies are the foundation of oral health.
By Scott D. Benjamin, DDS
It is not uncommon to see dental offices promote "free exams" or "free consultations." Practices use these offers as "loss leaders" to initially attract patients, in hopes of ultimately performing more profitable procedures. Even more unfortunate is the fact that these types of statements greatly misrepresent the significant amount of knowledge and expertise required to properly perform these valuable procedures. This has significantly and erroneously devaluated the perceived importance, benefit, and reimbursement of a complete and thorough enhanced examination for patients, clinicians, and third-party payers.
Some of dentistry’s most significant—and often overlooked—advances in recent years have been in the area of diagnostic technologies. These technologies can assist oral healthcare clinicians with the assessment of patients’ dental, oral, and systemic health status and needs; the most important responsibility a clinician has. However, dental practitioners too often focus on the restorative treatment procedures they are performing, and overlook the tremendous value these new diagnostic modalities provide to both patients and clinicians.
As patients’ health situations become increasingly complex, the practitioner’s need for these advanced technologies has never been greater. These technologies provide a wide range of information that can assist with the evaluation process and case management. The assessment of the dentition, periodontium, oral mucosa, salivary function, and systemic conditions have all been enhanced with these technologies.
Electronic Health Records and Interactive Patient Records and Databases
The knowledge of the patient’s health history and present status is the foundation of all healthcare. Being able to accurately obtain, evaluate, and share this knowledge is crucial in the diagnostic process. A multitude of situations and medications have a major impact on the health of the oral cavity. More than 800 medications are known to have a xerostomic effect. Others cause gingival inflammation, or may affect coagulation, and still others impact the balance of the flora of the oral cavity.
There are now dental practice management systems that recognize the importance of the patient’s overall health status, and are making it the foundation of patient care and management. These systems are integrating Internet- and knowledge-based platforms, such as Lexi-Comp Online (Lexi-Comp, Inc, www.lexi.com), that assess clinical and medication information with user-friendly interfaces. These systems help practitioners simplify the identification, recording, and interactions of prescribed and over-the-counter medications and treatments that their patients are using.
Once this information has been obtained, these programs assist clinicians in making faster and safer point-of-care decisions, which in turn enables better diagnosis and case management. Decision-support software can alert the practitioner to the potential effects that medications and treatments may have on the patient’s oral cavity. It can also guide clinicians’ decisions regarding appropriate dental treatments and pharmacology; based on their interaction with the patient’s other health circumstances and concerns.
An accurate electronic health record (EHR) containing all of the patient’s health information enables clinicians to collaborate in real-time with other healthcare providers. This collaboration further enhances the diagnostics process, and facilitates coordinated care to obtain the best possible outcomes.
Enhanced Oral Examination and Assessment
Only a decade ago, the devices and technology used to perform a thorough oral examination consisted of an intraoral mirror, explorer, and 2-dimensional radiographs and photographs. When necessary, an electronic pulp tester was occasionally used. With the new millennium came an explosion of diagnostic detection devices and technologies to evaluate the hard and soft structures as well as saliva.
All clinicians must understand that these new technologies are to be used in addition to the "gold" standard processes of visual and tactile examination, and not as a replacement. The goals of these technologies are to provide the practitioner with additional information to assist in making more accurate clinical decisions.
The diagnostic process involves three very distinct steps that often get blurred together, especially when evaluating diagnostic devices (Table 1). The first step in the process is detection, which is designed to determine whether any abnormal process or disease condition is present. The second step is the assessment of the condition. One of the primary goals of the assessment process is to determine what other screening and examination techniques should be performed. Diagnosis is the third and final stage, at which point a healthcare professional or professionals compile all the information available from multiple sources and assessment techniques to arrive at a consensus decision regarding the abnormality.
A single modality, examination process, or device alone does not establish the diagnosis of a condition. This concept is often overlooked when clinicians evaluate which diagnostic, or, more accurately, which detection or assessment technologies might be most appropriate and beneficial for their practices.
Adjunctive screening technologies are divided into two basic categories. A panoramic radiograph, a field-of-view technology that assesses a wide region or area, exemplifies the first type. The second type is a site-specific technology that focuses on a limited area. A bitewing radiograph evaluating the interproximal areas of the dentition for caries would be an example of this type.
A field-of-view screening technology’s initial role is to assess a wide region to discover abnormalities or irregularities. Some of these modalities also have the ability to provide site-specific information to the clinician once an area has been detected. An example of this type of device is a fluorescence mucosal screening technology, such as the VELscope Vx (LED Dental, Inc, www.velscope.com) and DentLight DOE (DentLight, Inc, www.dentlight.com). These instruments are initially used to perform a cursory fluorescence screening after the clinician’s visual and tactile examination. This screening is performed to look for any abnormal fluorescence patterns or responses, such as an unexpected loss of fluorescence.
If an area of concern is discovered in the tissue, the clinician re-examines the specific area with all of the modalities necessary and available to establish a clinical impression or working diagnosis for the area of concern. In this case, the clinician would initially re-examine the area tactilely, under standard white light and with fluorescence, giving a concentrated (site-specific) evaluation to details of the area of concern. Site-specific considerations that assist in the diagnostic process would include the location, shape, borders, and duration of the condition.
Salivary testing is another example of a wide-ranging screening technology. Salivary analysis can provide valuable insights for enhanced patient care, and serves as an important assessment modality in the fight against periodontal disease, oral cancer, and other diseases. By collecting saliva and monitoring its flow, clinicians can evaluate the functionality of the salivary glands and assess some of the patient’s potential health risks and the related effects of decreased salivary production. These salivary assessments can assist in creating a scientific basis for individualized comprehensive therapy, treatment protocols, and an appropriate course of action.
Clinicians have the ability to use funneled collection tubes to simply obtain salivary samples for laboratory evaluation. Laboratories such as OralDNA® Labs perform tests that can assist in the appraisal of the health status or risk for a multitude of patients’ health conditions. These tests enable clinicians to identify patients whose genetic susceptibility to periodontal disease may put them at increased risk. This genetic testing for the interleukin-1 (IL-1) gene cluster, a significant inflammatory mediator, complements other periodontal screening procedures and other salivary bacterial DNA testing that can be performed for specific oral pathogens.
Saliva analysis can also be used as a non-invasive screening tool to identify the type(s) of oral human papilloma virus (HPV) present in the oral cavity. Studies have identified several high-risk strains of HPV—especially the variants HPV-16 and HPV-18—as potential etiologic agents in the development of squamous cell carcinoma of the head and neck (SCCHN).1,2 This increased knowledge enables the clinician to discuss the potential risk of SCCHN with the patient and determine the appropriate referral and monitoring recommendations.
Cytology, the harvesting of disaggregated cells and related microscopic material, may be used as either a field of view or site-specific assessment tool. A clinician may be able to obtain a considerable amount of information on the patient’s health status, depending on the collection method, transport mechanisms used, and tests requested. Cytology may yield important screening information when the patient has health issues that may preclude performing a surgical biopsy or other procedures at that time.
Liquid-based cytology of the oral cavity is a relatively new, FDA-approved screening technique. The procedure involves a minimally invasive collection of transepithelial mucosa cells and other microbiology with a nylon bristle brush, with minimal or no discomfort to the patient. The collected material and brush are then placed into a special liquid preservative/fixative bottled solution for transportation to the laboratory for processing and evaluation. With liquid cytology, the clinician can request tests for several generalized oral conditions such as herpes simplex infection and candidiasis.
Liquid-based and conventional transepithelial cytology smears, which are often referred to as a "brush test" or the OralCDx® (OralScan Laboratories Inc, www.sopreventable.com) are most commonly used to assess specific areas that have been detected with other screening methods. The brush test is frequently used on suspicious leukoplakia or erythroplakia areas, to aid in determining the presence or lack of a potential dysplastic change.
In this role, cytology is an extremely valuable modality used to evaluate an area of concern for dysplasia, a potentially malignant condition. Cytology assists in helping to determine if an immediate invasive full-thickness biopsy procedure should be performed, or if the area should be closely monitored. Cytology is not a substitute for the traditional, "gold standard" surgical biopsy technique that removes architecturally intact tissue for histological evaluation. The only accepted method of diagnosing an oral cancer is a surgical biopsy with a microscopic examination, performed by an oral pathologist to evaluate all of the available information.
Dental caries treatment and management has always been a fundamental part of dentistry. Caries and enamel decalcification management currently involves early intervention. This requires early identification of the disease process, and administering restorative treatment before the end stage disease of dentinal cavitation is present.3 The present goal is to control or reverse early stage disease without surgical intervention (restoration). Early discovery of the disease’s decalcification process facilitates the ability to contain, arrest, or remineralize the lesion, which is of significant value to the patient. Restoring health is the ultimate goal when any disease process is discovered.
In addition to ionizing radiography, several adjunctive modalities using very different technologies have been developed to aid in the early discovery of the caries and enamel decalcification. These technologies include the use of radiographic imaging software, fluorescence imaging devices, and electrical impedance spectroscopy.
Radiographic evaluation has been used to detect caries for almost a century. However, studies have shown that decay is difficult to detect in radiographs, unless caries are larger than 2 mm to 3 mm deep into dentin, or one third of the buccal–lingual dimension.4 Digital radiography has greatly enhanced the clinician’s ability in this area, allowing for the use of various tools to enhance the contrast and brightness of an image, which enables better discovery.
LOGICON Caries Detector™ Software (Carestream Dental, www.carestreamdental.com) is a unique tool used to assist dentists in evaluating radiographs for the presence of proximal caries. LOGICON Software is the first diagnostic tool of its type to be demonstrated as efficacious in a clinical study under normal dental operating conditions, and is the first software of its kind to be approved by the FDA at its highest level.5 Using mathematical methods of neural network techniques developed for image analysis in the defense industry, the tool analyzes an area designated by the clinician, outlines the radiolucency, and plots the tooth density plot and lesion probabilities.6 These features are used to classify lesions, decalcification confined to the outer half of enamel, decalcification penetrating more than halfway through the enamel but not into the dentin, and carious lesions penetrating through the enamel but less than halfway through the dentin.
Three-dimensional imaging using cone beam tomography is becoming more commonplace in everyday oral healthcare, and its value to diagnostics and treatment planning is almost limitless.
Studies have demonstrated that the use of laser fluorescence can be more effective than conventional visual and radiographic techniques for the detection of well-established dentinal lesions and cavities.7,8 The DIAGNOdent (KaVo Dental, www.kavousa.com), the Spectra™ Caries Detection Aid (Air Techniques, www.airtechniques.com) and the SOPROLIFE light-induced fluorescence evaluator (Acteon Imaging, www.acteongroup.com) are caries detection devices that use light energy that is free from ultraviolet or ionizing radiation. They use visible-light fluorescence technology to differentiate between healthy tooth structure and areas of carious activity. These non-invasive fluorescence technologies function by emitting light energy that is absorbed into metabolites of cariogenic bacteria and material called porphyrins. The light-induced fluorescence of the porphyrins is accomplished by converting the absorbed energy to a different but very specific wavelength of light, and is emitted back to the device. The intensity and wavelengths of light received by the device’s sensors indicates the amount of decay present in the area of interest.
Each of these devices has unique characteristics and methods for reporting findings. The DIAGNOdent readings are shown on its display, and an audio signal allows the operator to hear changes in the scale values. The Spectra™ imaging device provides numerical and color readings to measure the extent of decay. SOPROLIFE filters the colors from the reflected signal, then amplifies and displays in color the fluorescence light it received.
The imaging capabilities of the Spectra and the SOPROLIFIFE enable the devices to be used during the treatment in place of caries, disclosing dyes to help ensure that complete caries removal has been accomplished. They are also excellent tools for patient education. These devices help to promote better oral hygiene by allowing the patient to visualize findings on the computer’s monitor. The SOPROLIFE can also function as an intraoral camera.
The concept of using an electrical signal to evaluate teeth for caries dates back to the 1950s.9,10 The use of multiple frequency impedance spectroscopy for caries and decalcification detection was initially reported in the literature in 1996.11,12 The recently introduced CarieScan PRO™ (CarieScan, http://us.cariescan.com) is a battery-powered detection aid that uses alternating current impedance spectroscopy technology (ACIST) to assess the coronal region on the tooth for primary caries and decalcification.
The CarieScan Pro uses direct multiple frequency impedance assessments of caries-related changes in the enamel and dentin of the tooth structure. These assessments are monitored and evaluated by a microprocessor contained within this handheld device. The findings are displayed with both a numerical readout and with green–yellow–red indicator lights, indicating sound tooth structure, initial carious breakdown or decalcification contained within the enamel, and an established dentinal carious lesion.
A key benefit of both fluorescence and impedance technologies is the absence of ionizing radiation and its associated risks. This enables these technologies to be used to monitor and assess the impact of preventive interventions based on the patient’s need and status.
When a pathological condition exists, the earliest possible discovery is the diagnostic goal, enabling corrective measures to be implemented to reestablish health. All of the diagnostic processes discussed have the common goal of providing practitioners with additional and better quality information to enhance and facilitate "best practices" in diagnostic decisions. They are all adjunctive devices to be used in addition to the standard examination techniques. It is essential that the patients understand and that clinicians know the limitations of each diagnostic modality when they are used. It is also imperative to remember that diagnosis is a decision made by a healthcare professional after evaluating and compiling all information available, from multiple sources and assessment techniques, and not by a device. Decisions made with enhanced knowledge will lead to better-quality and more appropriate diagnosis, prognosis, and case management leading to improved outcomes and an enriched quality of life for the patient.
However, clinicians, patients, and third-party payers such as governmental agencies and insurance plans must value and respect these enhanced diagnostic processes for the great benefits they can provide. The ultimate goal is improved health and an enhanced quality of life.
The author is a stockholder in LED Medical Diagnostics and a current consultant for Sirona Dental, LLC.
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About the Authors
Scott D. Benjamin, DDS
Sidings, New York