Introduction to Preliminary Diagnosis of Oral Lesions

After studying this chapter, the student will be able to:

1. Define each of the terms in the vocabulary list for this chapter.

2. List and define the eight diagnostic categories that contribute to the diagnostic process.

3. Name a diagnostic category and give an example of a lesion, anomaly, or condition for which this category greatly contributes to the diagnosis.

4. Describe the clinical appearance of Fordyce granules (spots), torus palatinus, mandibular tori, and lingual varicosities and identify them in the clinical setting or on a clinical photograph.

5. Describe the radiographic appearance and historical data (including the age, sex, and race of the patient) that are relevant to periapical cemento-osseous dysplasia (cementoma).

6. Define “variant of normal” and give three examples of these lesions involving the tongue.

7. List and describe the clinical characteristics and identify a clinical picture of median rhomboid glossitis, geographic tongue, ectopic geographic tongue, fissured tongue, and hairy tongue.

8. Describe the clinical and histologic differences between leukoedema and linea alba.

9. Define leukoplakia and erythroplakia.

10. Discuss the two risk types of human papillomavirus covered in this chapter.

Vocabulary

Clinical Appearance of Soft Tissue Lesions

Bulla

(adjective, bullous; plural, bullae) A circumscribed, elevated lesion that is more than 5 mm in diameter, usually contains serous fluid, and looks like a blister.

Lobule

(adjective, lobulated) A segment or lobe that is a part of the whole; these lobes sometimes appear fused together (Figure 1-1).

FIGURE 1-1 Lobulated torus palatinus.

Macule

An area that is usually distinguished by a color different from that of the surrounding tissue; it is flat and does not protrude above the surface of the normal tissue. A freckle is an example of a macule.

Papule

A small, circumscribed lesion usually less than 1 cm in diameter that is elevated or protrudes above the surface of normal surrounding tissue.

Pedunculated

Attached by a stemlike or stalklike base similar to that of a mushroom (Figure 1-2).

FIGURE 1-2 Fibroma with a pedunculated base. Arrow points to the stemlike base.

Pustules

Variously sized circumscribed elevations containing pus.

Sessile

Describing the base of a lesion that is flat or broad instead of stemlike (Figure 1-3).

FIGURE 1-3 Fibroma with a sessile base.

Vesicle

A small, elevated lesion less than 1 cm in diameter that contains serous fluid.

Soft Tissue Consistency

Nodule

A palpable solid lesion up to 1 cm in diameter found in soft tissue; it can occur above, level with, or beneath the skin surface.

Palpation

The evaluation of a lesion by feeling it with the fingers to determine the texture of the area; the descriptive terms for palpation are soft, firm, semifirm, and fluid filled; these terms also describe the consistency of a lesion.

Color of Lesion

Colors

Red, pink, salmon, white, blue-black, gray, brown, and black are the words used most frequently to describe the colors of oral lesions; they can be used to identify specific lesions and may also be incorporated into general descriptions.

Erythema

An abnormal redness of the mucosa or gingiva.

Erythroplakia

A clinical term used to describe an oral mucosal lesion that appears as a smooth red patch or granular red and velvety patch.

Leukoplakia

A clinical term for a white plaquelike lesion on the oral mucosa that cannot be rubbed off or diagnosed as a specific disease.

Pallor

Paleness of the skin or mucosal tissues.

Size of Lesion

Centimeter (cm)

One-hundredth of a meter; equivalent to a little less than one-half inch (0.393 inch) (Figure 1-4).

FIGURE 1-4 A ruler measuring centimeters is used to measure all specimens submitted for microscopic examination.

Millimeter (mm)

One-thousandth of a meter (a meter is equivalent to 39.3 inches); the periodontal probe is of great assistance in documenting the size or diameter of a lesion that can be measured in millimeters (general terms such as small, medium, or large are sometimes used, but these terms are not as specific) (Figure 1-5).

FIGURE 1-5 A, Probe measuring the diameter of a fibroma with a sessile base. B, Gutta-percha point used to explore a radiographic defect. C, Periodontal probe placed before a radiograph.

A cleft or groove, normal or otherwise, showing prominent depth.

Papillary

Resembling small, nipple-shaped projections or elevations found in clusters.

Smooth, rough, folded

Terms used to describe the surface texture of a lesion.

Radiographic Terms Used to Describe Lesions in Bone

Coalescence

The process by which parts of a whole join together, or fuse, to make one.

Diffuse

Describes a lesion with borders that are not well defined, making it impossible to detect the exact parameters of the lesion; this may make treatment more difficult and, depending on the biopsy results, more radical (Figure 1-6).

FIGURE 1-6 Squamous cell carcinoma involving the alveolar bone and hard palate showing diffuse borders. (Courtesy Drs. Paul Freedman and Stanley Kerpel.)

Multilocular

Describes a lesion that extends beyond the confines of one distinct area and is defined as many lobes or parts that are somewhat fused together, making up the entire lesion; a multilocular radiolucency is sometimes described as resembling soap bubbles; an odontogenic keratocyst often presents as a multilocular, radiolucent lesion (Figure 1-7).

FIGURE 1-7 Odontogenic keratocyst (arrow), illustrating a multilocular lesion. (Courtesy Dr. Victor M. Sternberg.)

Radiolucent

Describes the black or dark areas on a radiograph; radiant energy can pass through these structures; less dense tissue such as the pulp is seen as a radiolucent structure (Figure 1-8).

FIGURE 1-8 Prominent pulp chambers, horns, and canals in mandibular molars.

Radiolucent and radiopaque

Terms used to describe a mixture of light and dark areas within a lesion, usually denoting a stage in the development of the lesion; for example, in a stage I periapical cemento-osseous dysplasia (cementoma) (Figure 1-9, A), the lesion is radiolucent; in stage II it is radiolucent and radiopaque (Figure 1-9, B).

FIGURE 1-9 A, Stage I periapical cemento-osseous dysplasia (cementoma). B, Stage II periapical cemento-osseous dysplasia (cementoma).

Radiopaque

Describes the light or white area on a radiograph that results from the inability of radiant energy to pass through the structure; the denser the structure, the lighter or whiter it appears on the radiograph; this is illustrated in Figure 1-10.

FIGURE 1-10 Amalgam restorations on the occlusal surfaces of the maxillary and mandibular molars.

Root resorption

Observed radiographically when the apex of the tooth appears shortened or blunted and irregularly shaped; occurs as a response to stimuli, which can include a cyst, tumor, or trauma; Figure 1-11 illustrates resorption of the roots as a result of a rapid orthodontic procedure (see Figure 1-27); external resorption arises from tissues outside the tooth such as the periodontal ligament, whereas internal resorption is triggered by pulpal tissue reaction from within the tooth; in the latter the pulpal area can be seen as a diffuse radiolucency beyond the confines of the normal pulp area.

FIGURE 1-11 Resorption of the roots on maxillary anteriors as a result of rapid orthodontic movement.

Scalloping around the root

A radiolucent lesion that extends between the roots, as seen in a traumatic bone cyst; this lesion appears to extend up the periodontal ligament (Figure 1-12).

FIGURE 1-12 Traumatic bone cyst (arrows) around the roots. (Courtesy Drs. Paul Freedman and Stanley Kerpel.)

Unilocular

Having one compartment or unit that is well defined or outlined, as in a simple radicular cyst (Figure 1-13).

FIGURE 1-13 Radicular cyst (arrow) at the apex of the maxillary lateral incisor, illustrating a unilocular lesion.

Well circumscribed

Term used to describe a lesion with borders that are specifically defined and in which one can clearly see the exact margins and extent (Figure 1-14).

FIGURE 1-14 Well-circumscribed median palatal cyst (arrow).

To understand the material in this text, it is imperative that the reader approach it in a systematic manner. Significant time is spent in the dental hygiene curriculum identifying and describing normal structures. Before one can identify the abnormal condition, it is necessary to have a solid understanding of the basic and dental sciences such as human anatomy and physiology, histology, and dental anatomy. Once one has a solid understanding of normal structures and those that are variants of normal, findings that deviate from normal and pathologic conditions are recognized more easily. The preliminary evaluation and description of these lesions are within the scope of dental hygiene practice and are truly among the most challenging experiences in clinical practice.

In the first part of this chapter the definitions of commonly used terms that describe the clinical and radiographic features of a lesion, including terms used for normal, variants of normal, and pathologic conditions discussed throughout this text, are presented. The reader is encouraged to use these terms in the clinical setting so that they become part of an everyday professional vocabulary, thereby facilitating communication between the hygienist and other dental practitioners in the clinical setting.

The second part of this chapter focuses on the eight diagnostic categories that provide a systematic approach to the preliminary evaluation of oral lesions. Each area is described, and the strength of that area in the diagnostic process is illustrated using specific examples of lesions.

The final part of the chapter includes conditions that are considered variants of normal and those that are benign conditions of unknown cause. Most are diagnosed from their distinct clinical appearance and history.

The Diagnostic Process

Making A Diagnosis

How is a diagnosis made? What are the essential components? The answers to these questions begin with data collection. The process of diagnosis requires gathering information that is relevant to the patient and the lesion being evaluated; this information comes from various sources.

Certain distinct diagnostic categories should be thought of as pieces in a puzzle, with each piece playing a significant role in the final diagnosis. The eight categories that contribute segments of information leading to the definitive or final diagnosis are (1) clinical, (2) radiographic, (3) historical, (4) laboratory, (5) microscopic, (6) surgical, (7) therapeutic, and (8) differential findings. It is important to note that usually one area alone does not provide sufficient information to make a diagnosis; the strength of the diagnosis is often derived from one or two areas. As the dental hygienist becomes more aware of the diseases and conditions discussed in this text, it will be most helpful to use the diagnostic categories as a guide to evaluating lesions..

Clinical Diagnosis

Clinical diagnosis suggests that the strength of the diagnosis comes from the clinical appearance of the lesion. By observing the area in a well-illuminated clinical setting and palpating it if necessary, the clinician can establish a diagnosis for some lesions on the basis of color, shape, location, and history of the lesion. When a diagnosis can be made on the basis of these unique clinical features, biopsy or surgical intervention is not necessary. Examples of lesions that can be clinically diagnosed are Fordyce granules (Figure 1-15), torus palatinus (Figure 1-16), mandibular tori (Figure 1-17), melanin pigmentation (Figure 1-18), retrocuspid papillae (Figure 1-19), and lingual varicosities (see Figure 1-52). These lesions are described later in this chapter.

FIGURE 1-16 Lobulated torus palatinus. (Courtesy Dr. Edward V. Zegarelli.)

FIGURE 1-17 *Arrows* point to mandibular tori.

FIGURE 1-19 *Arrows* point to the retrocuspid papillae on the gingival margin of the lingual aspect of the mandibular cuspids.

Other benign conditions of unknown cause that are recognized by their distinct clinical appearance include fissured tongue (Figure 1-20), median rhomboid glossitis (Figure 1-21), geographic tongue (Figure 1-22), and hairy tongue (Figure 1-23). These conditions are also discussed later in this chapter.

FIGURE 1-21 Median rhomboid glossitis *(top arrow)* and geographic tongue *(bottom arrows)*.

FIGURE 1-22 Geographic tongue. *Arrows* point to areas of depapillation.

FIGURE 1-23 A, White hairy tongue. B, White hairy tongue showing a circumvallate papilla *(arrow)*. C, Black hairy tongue.

Sometimes the diagnostic process requires historical information in addition to the clinical findings. For example, an amalgam tattoo (focal argyrosis) can be observed as a blue-to-gray patch on the gingiva or mucosa where an amalgam restoration is or has been located (Figure 1-24). Although this condition is usually easily observed and a clinical diagnosis made, any history involving the area can still be very helpful in confirming the clinical impression. The patient in Figure 1-24 had root canal therapy and a retrograde amalgam on a deciduous tooth. The amalgam tattoo is observed in the apical area of the permanent central incisor; no evidence of an amalgam restoration exists in the entire anterior area. The history helped confirm the clinical diagnosis.