**Oral Pathology module**
<br>
**Epithelial disorders 1;**
**Reactive, benign and pigmented**
**lesions**
<br>
DENT4217 A/Prof Omar Kujan
BDS DipOPath MDSc MFDS RCPS FHEA FRCPath PhD FFOMP(RCPA)
**Acknowledgement**
of country
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campus is situated on Noongar land, and that Noongar
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and knowledge.
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**Learning outcomes**
1. Describe common reactive and benign epithelial lesions
of the oral mucosa.
2. Describe common reactive and benign pigmented
lesions of the oral mucosa.
Reactive and
benign
pigmented
disorders
**Reactive, benign and pigmented oral lesions** Important cause of benign mucosal lesions
| Prevalence | Lesion | Cause |
|:-----------|:------------------------------|:---------------------------|
| Common | leukoedema | Normal variation |
| | Frictional keratosis | Physical injury (friction) |
| | Cheek biting | Physical injury (trauma) |
| | Fordyce's granules | Developmental |
| | Nicotine stomatitis | Pipe smoking |
| | Thrush | Candidal infection |
| | Physiologic and racial pigmentation | Normal variation |
| Less common| Chemical trauma | Caustic chemicals |
| | Hairy leukoplakia | EBV |
| | White sponge naevus | Developmental |
| | Squamous papilloma | HPV |
| | Verruca vulgaris | HPV |
| | Condyloma acuminatum | HPV |
| | Oral melanotic macules | Uncertain |
| | Oral nevi | Uncertain |
| | Denture related stomatitis | Uncertain |
| | Verruciform xanthoma | Uncertain |
| | Skin grafts | Iatrogenic |
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# **CANDIDOSIS**
---
* Three types of candidal infection cause white patches and are relatively common.
* **Thrush** (acute candidosis) is readily distinguishable from other white lesions. The patches can easily be wiped off, and the condition is sore.
* **Chronic hyperplastic candidosis** and **chronic mucocutaneous**
* **Candidosis** forms discrete white plaques similar clinically to other types of leukoplakia
**CANDIDOSIS**
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**Thrush: key features**
* Acute candidosis
* Painful
* Secondary to various predisposing factors
* **common in HIV infection and indicates low immunity**
* Creamy soft patches, readily wiped off the mucosa
* Smear shows many Gram-positive hyphae
* Histology shows hyphae invading superficial epithelium
**SKIN GRAFTS**
* Skin grafts typically appear sharply demarcated, smooth and paler than the surrounding mucosa and occasionally grow hairs
* After many years grafts change in appearance and are less easy to differentiate from a leukoplakia
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**Pigmentation**
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* Racial
* Food/drugs
* Chlorhexidine
* Minocycline
* Zidovudine
* Endocrinological
* Pregnancy
* Addison's disease
* Others
* Amalgam tattoo
* Lentigines
* Melanoma
* Nevi
* Peutz-Jegher's syndrome
* Kaposi's sarcoma
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**MEDICATION-INDUCED PIGMENTATION**
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* Tetracyclines (including the
semisynthetic minocycline and
doxycycline),
* Quinoline antimalarial medications
(including hydroxychloroquine,
mepacrine, and quinacrine)
* Psychotropic drugs such as retigabine,
clofazimine and imatinib, a tyrosine
kinase inhibitor.
Breakdown products of antimalarial drugs, minocycline, and
imatinib chelate with iron or melanin and deposit within the lamina
propria. Birth control pills lower cortisol levels and increase
adrenocorticotrophic hormone (ACTH) levels, leading to the
stimulation of melanocytes.
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**ORAL MELANOTIC MACULE**
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•Discrete, usually solitary (sometimes multiple), tan-to-
brown-to-black, painless macules are evenly pigmented,
less than 1 cm, and frequently occur on the lower
vermilion (labial melanotic macule, 33% of cases), gingiva
and palatal mucosa, or buccal mucosa
•Multiple melanotic macules may be idiopathic Addison
disease, and in syndromes such as the Laugier-Hunziker
syndrome (with melanonychia), neurofibromatosis,
Peutz-Jeghers syndrome, McCune-Albright syndrome,
Carney syndrome complex, LEOPARD
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Clinical images of oral and perioral pigmentation.
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**Melanotic macule**
**Postinflammatory hypermelanosis, e.g., smoker's melanosis**
**Melanoacanthosis**
* No melanocytic hyperplasia
* Mild acanthosis and little spongiosis
* Vascular ectasia
* Inflammation 0 to 1+
* Mild or no melanocytic hyperplasia
* Acanthosis and spongiosis
* Vascular ectasia
* Inflammation 1+ to 3+
* Prominent melanocytic hyperplasia
* Acanthosis and spongiosis
* Vascular ectasia
* Inflammation 1+ to 3+
**FIG. 9.11** Relationship between melanotic macule, postinflammatory hypermelanosis, and melanoacanthosis.
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Below is the extracted text from the image, using the PDF text for context and aiming to match the formatting as much as possible.
**ORAL MELANOCYTIC NEVUS**
•Most common site is the palatal mucosa (34% to 44%), with other sites being the mucobuccal fold, buccal mucosa, lip vermilion, and gingiva.
•They may be brown, blue-grey, black, or nonpigmented.
•The frequency in the oral cavity is as follows: intramucosal nevus (64% to 80%), blue nevus (8% to 17%), and compound nevus (6% to 17%); junctional and combined nevi are uncommon.
•Melanocytic nevi derive from melanocytes that originate from the neural crest.
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Intramucosal melanocytic nevus.
Melanocytes are heavily pigmented
near the surface.
Compound nevus: This is a
combination of intramucosal and
junctional nevus with nests of benign
melanocytes
clustered within the lower part of the
epithelium, often forming bulbous rete
ridges
**BLUE NEVUS**
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* Discrete proliferation of spindled melanocytes with variable melanin and benign spindled nuclei exhibiting dispersed chromatin and small nucleoli, scattered within densely collagenous stroma without hyperplasia of melanocytes within the epithelium
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| | **Macule** | **Nevi** | **Melanoacanthoma** | **OMM** |
|---|---|---|---|---|
| **Prevalence in** melanocytic lesions | 62% (48, 49) | 15% (48, 49) | 0.8% (48, 49) | 0.7% (48, 49) |
| **Color** | Gray to brown to black | Brown, bluish-gray or black, 15% non-pigmented 0.5cm | Brown or black | Variable |
| **Size (mean** diameter) | <1 cm | | Several centimeters | 4 cm |
| **Shape** | Flat, solitary & well-circumscribed | Well-demarcated but elevated | Flat or slightly raised | Asymmetric with irregular outline |
| **Commonly** occurred site | Lip & gingiva | Palate | Buccal mucosa | Hard palate & maxillary gingiva |
| **Causative factor** | Melanin deposition | Proliferation of melanocytes | Proliferation of keratinocytes & melanocytes | Uncontrolled growth of melanocytes |
| **Histopathologic features** | Melanin accumulation without an increase in melanocytes. | Polygonal & epithelioid nevus cells in the superficial. Cytoplasm transparent to light stained. | Many dendritic melanocytes, processes containing melanin & melanophagocytes in all strata of epithelium. | Large, vesicular nucleus & prominent nucleoli. Aggregated into sheets or alveolar groups. Neurotropic or desmoplastic configurations. |
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**SINGLE WHITE SPOT OR**
**SINGLE WHITE PLAQUE**
**Has a topical drug**
**recently been applied**
**to the area?**
**Yes**
**Chemical burn**
**No**
**Is it made out of stripes or**
**papules or a spot or plaque on**
**the dorsum of the tongue?**
**Yes**
**Lichenoid lesions or early**
**lichen planus**
**No**
**Is it on the palate with**
**small red spots?**
**Yes**
**Stomatitis**
**nicotina**
**Is it on the edge of the tongue?**
**No**
**Hairy leukoplakia**
**Yes**
**No**
**Is it formed of parallel white stripes**
**perpendicular to the edge?**
**Yes**
**Is it in contact with a**
**discrete cause of**
**chronic trauma?**
**Yes**
**Frictional**
**keratosis**
**Does the lesion disappear once**
**the trauma is removed?**
**No**
**Yes**
**No**
**Carcinoma in**
**situ or invasive**
**carcinoma**
**Positive**
**biopsy**
**Consider the (rare) possibility**
**of carcinoma and perform a biopsy**
**Homogeneous leukoplakia (idiopathic) or tobacco-related keratosis**
**Biopsy is negative for**
**carcinoma (dysplasia could**
**be present)**
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MULTIPLE WHITE SPOTS AND
MULTIPLE WHITE PLAQUES
**Are the lesions symmetrical and bilateral on the buccal mucosae?**
**No**
**Yes**
**The lesions do not involve or do not only involve the**
**buccal mucosa**
**Are there stripes and/or**
**papules present?**
**Are there stripes and/or papules present, especially on**
**the dorsum of the tongue?**
**Yes**
**No**
**Lichen**
**planus**
**No**
**No**
**Are any of the following present?**
- **Female patient**
- **No risk factors for cancer**
- **Lesion persistent after therapy**
- **Verrucous lesions also present**
**Is it simple white-grey**
**colouring of the buccal**
**mucosa? Does the**
**colour disappear whilst**
**stretching the cheecks?**
**Is there discrete**
**chronic trauma**
**to justify the**
**lesions even if**
**multiple?**
**Proliferative**
**verrucous**
**leukoplakia**
**Yes**
**Surface of lesion abraded**
**at the occlusal line?**
**No**
**Yes**
**Yes**
**Multifocal**
**homogeneous**
**leukoplakia**
**No**
**Leukoedema**
**No**
**Yes**
**Do the lesions**
**disappear after**
**removing the**
**trauma?**
**No**
**Yes**
**Yes**
**Young**
**patient and**
**spongy-like**
**appearance**
**of the**
**surface?**
**Excessive cheek biting**
**(anxious personality)**
**Frictional keratosis**
**Retro**
**commissural**
**lesions in**
**smoking?**
**Yes**
**White sponge naevus**
**No**
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**RED AND WHITE SPOTS AND PLAQUES**
Are there red spots on the dorsum of the tongue
due to the absence of filiform papillae and circled
by a white-yellow edge?
**Yes**
Are the lesions widespread?
**No**
Striped papules
and red bilateral
spots
**Yes**
Multiple spots and
plaques mostly white of
somewhat verrucous
appearance (absence of
papules and stripes)
Do they progress
cyclically and
migrate?
**Geographic**
**tongue (migratory**
**glossitis)**
**Lichen planus**
**Proliferative verrucous**
**leukoplakia**
It looks like lichen but it
is localised and it is not
cyclical and migrant
**No**
**Yes**
Is there a clear presence of
trauma or risk factors for
oral cancer?
Perform biopsy and immunofluorescence
**Chronic trauma**
**Alcohol**
**Tobacco**
**Lichenoid lesion**
(stop any drug therapy,
remove any metals)
Consider the
possibility of pre-
cancerous lesion or
early cancer and
perform biopsy
**Positive**
**biopsy**
**Early cancer**
**Lupus erythematosus**
Consider the
following
possibilities
**Non-homogeneous**
**leukoplakia**
**Candidal leukoplakia**
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**No**
Frictional keratosis with
erythema
Does the lesion disappear when removing the
trauma?
**Yes**
Quiz
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Join at
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References
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• Odell E. 2018. Cawson's Essentials of Oral Pathology and Oral
Medicine
• Woo SB. 2023. Oral Pathology. A Comprehensive Atlas and Text
• Sapp JP, Eversole LR, Wysocki GP. 2004. Contemporary oral and
maxillofacial pathology.
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Cartoon of a dentist telling a patient "You have acute gingivitis," and the smiling elderly patient responding, "Thank you!"
