Current Concepts in Preventive Dentistry
Course Number: 334
Course Contents
Four Types of Pathologies
Oral Leukoplakia – “White Lesion”
Etiology – an infection of the oral mucosa. Candidal leukoplakia is caused by fungus, candida albicans. Infected epithelial tissue can become hyperplastic with a formation of excess surface keratin (callused). Another common cause of leukoplakia is tobacco, typically cigarettes. Identifying leukoplakia is important, as a percentage of these white patches will transform to oral cancer.
Typical Visual Cues – a circumscribed white plaque that will not rub off with gauze. Most often found on the buccal mucosa, lateral border and ventral side of the tongue, floor of the mouth, and lips.
Demographics and Clinical Information – more common in adults, especially older men. Not as common in patients under 40 years of age. Diagnoses includes differential diagnoses ruling out other white lesions that can be rubbed off.
Treatment Recommendations – The type of treatment is determined by multiple factors, such as age, tobacco habits, medical status, and the location and size of the lesion. Often a biopsy is needed to determine its precancerous potential. For patients who diagnosed with moderate to severe dysplasia, AAOMP recommends a complete removal of the white patch, in order to prevent the development of oral cancer. One in three lesions will regrow. The chance of reoccurrence is greater with patients who continue to smoke. It is recommended the patient is reexamined periodically and repeat biopsies are generally advisable.
Clinical Significance – oral lesions found in tobacco users should be viewed with increased suspicion for possible precancerous or cancerous lesions.
Figure 6. Leukoplakia.
Image courtesy of AIDS Image Library
Erythroplakia – “Red Lesion”
Etiology – a chronic red macule that cannot be diagnosed as any other red lesion after differential diagnoses. Risk factors include chronic exposure to carcinogenic components found in all types of tobacco and ill-fitting dentures.
Typical Visual Cues – a flat or slightly raised lesion with a velvety appearance. May occur on the floor of the oral cavity, ventral area of the tongue, buccal mucosa, or the soft palate.
Useful Clinical Information – a painless and persistent lesion, found more commonly in adult males and patients who report tobacco use.
Treatment Recommendations – this lesion has approximately a 90% chance of premalignancy. If a biopsy reveals the lesion is premalignant, extensive therapy is indicated and the patient should be re-evaluated at regular intervals for other oral mucosal changes.
Clinical Significance – erythroplakia occurs less frequently than leukoplakia, but it is much more likely to exhibit evidence of premaligancy or malignancy.
Figure 7. Erythroplakia.
Image courtesy of NYU College of Dentistry
Squamous Cell Carcinoma
Etiology – idiopathic (unknown). More than 9 of 10 cancers diagnosed in the oral cavity and oropharynx are squamous cell carcinoma. Risk factors include: tobacco use, alcohol use, sun radiation, genetic predisposition, nutritional deficiency, immunosuppression, and infections, such as candidal leukoplakia and human papillomavirus.
Typical Visual Cues – early lesions appear as flat and scale-like cells, adjacent tissues commonly firm to palpation, and may have residual leukoplakia and/or erythroplakia.
Useful Clinical Information – more common in adult males, continuous enlargement, local pain, referred pain often to the ear, and paresthesia of the lower lip.
Treatment Recommendations – the patient is referred to the oral surgeon for biopsy and treatment. They will also be referred to a medical provider for appropriate treatment (radiation therapy, chemotherapy). The patient should be seen regularly in your practice for re-evaluation and counseled concerning their risk factors that contributed to cancer.
Clinical Significance – early diagnosis is crucial, as the presence of lymph node metastasis greatly worsens prognosis. Approximately 50% of patients have evidence of lymph node metastasis at time of diagnosis, that is why an extraoral examination is so critical with an intraoral examination. Patients who have had cancer are at greater risk of reoccurrence. The 5-year survival rate is 45-50%.
Figure 8. Squamous Cell Carcinoma.
Image courtesy of Associated Content
Malignant Melanoma
Etiology – a malignant neoplasm of melanin-producing cells. Chronic exposure to sun radiation and a fair complexion increases the risk for skin lesions.
Typical Visual Cues – larger than 0.5 cm in diameter, irregular margins, irregular pigmentation, any change in pigmentation, ulceration of the overlying mucosa, macular (superficial spreading) or elevated (nodular), and most often occurs on gingiva and the palate.
Useful Clinical Information – occurs most often in adult males, usually painless, rapidly enlarging.
Treatment Recommendations – refer to the oral surgeon for biopsy and treatment, as well as to the patient’s medical provider.
Clinical Significance – malignant melanoma is an extremely aggressive form of cancer, early diagnosis is crucial, as patients with oral melonoma generally have a poor prognosis. For skin mucosa, the 5-year survival rate is 65% and for oral mucosa the rate is 20%.
Figure 9. Melanoma.
Image courtesy of DoctorSpiller.com