DHY 207

Diagnostic Process

Definition of the Diagnostic Process

• The process of diagnosis requires gathering information that is relevant to the patient and the lesion being evaluated

• This information comes from various sources

The Diagnostic Process

• Clinical diagnosis

• Radiographic diagnosis

• Historial diagnosis

• Laboratory diagnosis

• Microscopic diagnosis

• Surgical diagnosis

• Therapeutic diagnosis

• Differential diagnosis

Clinical Diagnosis

• The strength of the diagnosis comes from the clinical appearance of the lesions

• Observe, palpate, and document

• Sometimes clinical diagnosis is all you need

• T or F: Clinical diagnosis may be enough to diagnosis

• True; Fordyce’s granules, torus palatinus, mandibular tori, melanin pigmentation, retrocuspid papillae

• How does the lesion present?

• Color

• Shape

• Location

• History of lesion

• Fordyce granules

• Torus palatinus

• Mandibular tori

• Melanin pigmentation

• Retrocuspid papillae

• Fissured tongue

• Geographic tongue

• Median rhomboid glossitis

• White hair tongue

• Circumvallate papillae

• Black hairy tongue

Clinical Diagnosis + Historical Information

• Amalgam tattoo

• Caused by fragment of amalgam that entered the oral mucosa

Radiographic Diagnosis

• In a radiographic diagnosis, the radiograph provides sufficient information to establish the diagnosis

• The presence of a fistula warrants a radiographic image

• Fistula: Pus-filled pimple

• Fistula is an infection and much be radiographed because the infection may reach the brain

• Periapical pathosis: Acute or chronic inflammatory lesion around the apex of a tooth root, most commonly caused by bacterial invasion of the pulp of the tooth

• External resorption

• External PDL wants to meet pulp

• Internal pulp wants to meet PDL

• Caries

• Compound odontoma

• Looks like little teeth

• “Odontoma” means benign tumor

• Complex odontoma

• Looks like a star explosion

Radiographic Diagnosis: Abnormalities

• Supernumerary teeth

• Medioden #8-9

• Mesial molar

• Impacted teeth

• Calcified pulp

Radiographic Diagnosis: Normal Anatomic Landmarks

• Nutrient canals

• Permanent dentition coming in

• Amalgam fragments and overhangs

• Eyeglasses frames

• Piercings

• Retained metals such as shotgun pellets or shrapnel

Historial Diagnosis

• Historial date constitute an important component in every diagnosis

• Occasionally when historical data are combined with observation of the clinical appearance of the lesion, the historical information constitutes the most important contribution to the diagnostic process

• Personal history

• Family history

• Amelogenesis imperfecta

• Dentinogenesis imperfecta

• Past and present medical and dental histories

• Medical conditions such as ulcerative colitis

• Drug history such as calcium channel blockers

• Gingival overgrowth

• Allergic reactions

• History of surgical procedures

• History of drug ingestion

• History of the presenting disease or lesion

Laboratory Diagnosis: Blood Chemistries, Urinalysis, and Cultures

• Radiographic appearance is a “cotton-wool effect” + elevated serum alkaline phosphatase level = Paget disease

Microscopic Diagnosis

• Often the main component of the definitive diagnosis

• Microscopic examination is of particular importance in the diagnostic process and therefore, although it is a form of laboratory diagnosis, it is discussed separately from laboratory diagnosis

• Adequate tissue sample is necessary

• Brush test can be used to obtain information from oral mucosal epithelium

• A circular brush is used to obtain cells from the full thickness of epithelium

• The results of this test may help determine whether a scalpel biopsy is needed to establish a definitive diagnosis

• A white lesion cannot be diagnosed on the basis of clinical appearance alone

• The microscopic appearance can vary from a thickening of epithelium to epithelial dysplasia, which can be premalignant

• Oral cancer is most likely found on the lateral border of the tongue and the floor of the mouth

• Red lesion is more likely to be cancer, not white

Surgical Diagnosis

• Diagnosis is made using the information gained during the surgical procedure

• Traumatic bone cyst

• May appear as a radiolucency that scallops around the roots

• When the lesion is opened surgically, an empty void is found

• Lingual mandibular bone cavity (static bone cyst or Stafne bone cyst)

• Surgical examination of the well-circumscribed, radiolucent area reveals salivary gland tissue entrapped during development

• Cysts are always lined with epithelium cells

• Stafne bone is a pseudocyst

Therapeutic Diagnosis

• Nutritional deficiencies are common conditions to be diagnosed by therapeutic means

• Angular cheilitis

• May be associated with a deficiency of B-complex vitamins

• Most commonly a fungal condition and responds to topical application of an antifungal cream or ointment such as Nystatin

• Necrotizing ulcerative gingivitis (NUG)

• Responds to hydrogen peroxide

• Why? NUG is caused by anaerobic bacteria. Hydrogen peroxide brings oxygen to the anaerobic environment

Differential Diagnosis

• That point in the diagnostic process when the practitioner decides which test or procedure is required to rule out the conditions originally suspected and to establish the definitive or final diagnosis

• A differential diagnosis is a listing of the probable cause of a particular disease manifestation or group of manifestations

• 1.) Describe the abnormality in clinical terms

• 2.) Determine a list of diseases/conditions that present with similar manifestations

• 3.) Eliminate some of the possible causes already listed by adding other factors that could be involved with the abnormality (chronic health condition, medications, patient age, and whether the patient has an other manifestations that are inconsistent with any of the listed possibilities)

• 4.) Rank the remaining possible causes according to the probability they are the causative agent

• 5.) Decide what additional information might be necessary to eliminate more of the possibilities, such as blood tests, biopsy, diagnostic radiographs, cultures of oral microbes, and medical consultations

• White lesions on tongue

• 1.) Measure & document location and appearance of lesion

• 2.) Ask how long it has been there

• 3.) Ask if they are biting their tongue

• 4.) Check if patient has malocclusion, broken restorations, or if they are clenching

• 5.) If none, come back in 2 weeks. If it’s still there then send out referral for surgical biopsy

Definitive Diagnosis

• All elements of the differential diagnosis have been eliminated except one

• Clinical appearance

• Radiographic appearance

• Response to therapy

• Biopsy or laboratory test/cultures

Hygienists’ Role in DIfferential Diagnosis

• Be observant

• Collect data

• Patient’s medical and dental health histories

• History of lesion

• Clinical description and evaluation

• Biopsy and microscopy reports

Extra and Intraoral Examinations

• Systematic sequence

• Observe then palpate

• Findings

• Atypical

• Pathologic

• Traumatic

• Infectious

• Benign

• Malignant

• Others

Final Words

• Don’t assume something is atypical or a variation of normal unless you are 100% sure

• Explain your concerns to your patient, include them in a decision to refer for further diagnostic measures

• Follow-up on patients asked to return for a reevaluation of a lesion

• Must document everything

• Once in doubt, refer it out