Ever looked in the mirror and spotted something unusual on the roof of your mouth? Those mysterious black spots can send anyone into a Google search at 2 AM. You’re not alone; thousands search for “what causes black spots on the roof of the mouth” every month.
We are going to walk you through exactly what those dark patches might be, from harmless melanin deposits to signs that warrant a dentist visit.
The truth is, most black spots in your mouth aren’t dangerous. However, knowing the difference between normal pigmentation and something that requires attention can save you both unnecessary worry and potential health issues.
But before you self-diagnose with something you read on WebMD, let me show you what doctors look for when they see these symptoms.
Common Causes of Black Spots on the Roof of the Mouth
Oral Melanoacanthoma
Oral melanoacanthoma is a rare, benign condition that appears as brown-black spots in the mouth. These spots typically develop suddenly and grow quickly, often in response to tissue injury inside the mouth. They commonly appear on the inner lining of the cheeks (buccal mucosa), but can also develop on the roof of the mouth (palate), gums, inner lips, and other oral surfaces. Oral melanoacanthoma is more common in young adults around age 35, with women being affected more frequently than men at a ratio of 3:2. The condition is particularly prevalent in individuals with darker skin tones.
Oral Melanotic Macule
Oral melanotic macules are harmless spots that resemble freckles in the mouth. These flat, small lesions typically measure between 1-8 millimeters in diameter with well-defined borders and uniform coloration ranging from brown to grayish-brown. They most commonly appear on the lips (especially the lower lip), gums, inner cheek, or roof of the mouth. While doctors aren’t certain about their exact causes, some people are born with them, while others develop them later in life. These benign spots don’t cause any symptoms and don’t require treatment unless they change in shape, size, or color.
Physiologic Pigmentation
Physiologic pigmentation refers to natural variations in oral tissue coloration that occur without any underlying pathology. This normal pigmentation often appears as diffuse, symmetrical darkening in the mouth. It is particularly common in individuals with darker skin tones and is attributed to increased melanin production. Unlike other conditions, physiologic pigmentation is typically present from birth or develops gradually over time, remains stable, and requires no treatment as it represents a normal variation rather than a medical condition.
Traumatic Injuries and Bruising
The mouth, including the roof, can sustain injuries just like any other part of the body. Falling, eating something with sharp edges, or even aggressive brushing can cause bruising in the mouth. These bruises typically appear as dark red, purple, or black spots. Minor bleeding and pain may accompany the bruise, which usually heals on its own without medical intervention. However, if bruising occurs frequently without an apparent cause, it could indicate conditions affecting blood clotting, such as thrombocytopenia, which would require medical attention.
Eruption Hematoma
An eruption hematoma occurs when a tooth is about to emerge through the gums, creating a cyst filled with fluid. When blood mixes with this fluid, it creates a dark purple or black appearance, known as an eruption hematoma. This commonly happens when the eruption cyst sustains an injury from a bump or fall. Eruption hematomas are particularly common in children as their baby teeth and permanent teeth come in. These hematomas typically resolve on their own once the tooth emerges. In cases where the tooth doesn’t break through naturally, a doctor may surgically open the cyst to facilitate tooth eruption.
Medical Conditions That Can Cause Mouth Pigmentation
Addison’s Disease
Addison’s disease, also known as primary adrenal insufficiency, is an endocrine disorder characterized by the reduced production of glucocorticoid hormones due to progressive destruction of the adrenal cortex. This destruction is typically caused by autoimmune disease, cancer, or infection. The diminished production of adrenocorticoid hormones leads to dysfunction of the hypothalamus-pituitary-adrenal gland axis, resulting in elevated levels of adrenocorticotropic hormone (ACTH).
The oral manifestations of Addison’s disease are considered pathognomonic and may be the first sign of the condition. Hyperpigmentation of the oral mucosa affects up to 92% of patients and can precede other manifestations by up to 10 years. This pigmentation appears as diffuse brown to black macules in the oral cavity, particularly on the buccal mucosa, gingiva, tongue, hard palate, and lips.
The mechanism behind this hyperpigmentation involves the increased production of melanocyte-stimulating hormone (MSH) and other pro-opiomelanocortin byproducts. As adrenal insufficiency progresses, the lack of feedback inhibition leads to excessive secretion of ACTH from the pituitary gland, which stimulates melanocytes in the skin and mucosa through MSH receptors, resulting in increased melanin production and deposition.
Diagnosis of these oral pigmented lesions primarily relies on the patient’s clinical history and comprehensive examination. Treatment focuses on managing the underlying adrenal insufficiency with glucocorticoid and mineralocorticoid replacement therapy, which may lead to a gradual decrease in mucosal pigmentation.
Peutz-Jeghers Syndrome
Peutz-Jeghers Syndrome (PJS) is a rare hereditary autosomal dominant disorder characterized by intestinal polyposis and distinctive mucocutaneous pigmentation. The condition is linked to mutations in the STK11 gene located on chromosome 19p13.3, which predisposes affected individuals to a significantly higher risk of developing various types of cancer, particularly in the gastrointestinal tract and breast.
The oral manifestations of PJS include characteristic melanotic macules that typically appear on the lips and inside the mouth. These pigmented lesions present as small (1-5 mm), flat, dark brown to black spots that are well-demarcated. The labial mucosa is the most commonly affected site, though pigmentation can also occur on the buccal mucosa, gingiva, hard and soft palates, and tongue.
Histologically, these oral lesions show increased melanin deposition in the basal layer of the epithelium without a corresponding increase in melanocyte count. The diagnosis of PJS can be made when two or more histologically confirmed Peutz-Jeghers polyps are present, or when any polyp is found along with the characteristic mucocutaneous pigmentation and a family history of the syndrome.
Laugier-Hunziker Syndrome
Laugier-Hunziker Syndrome is a rare acquired condition characterized by macular hyperpigmentation of the oral mucosa and lips, frequently associated with longitudinal pigmentation of the nails. Unlike PJS, this syndrome has no known genetic basis and is not associated with internal malignancies or polyps.
The oral pigmentation in Laugier-Hunziker Syndrome appears as multiple brown to black macules that can affect any part of the oral mucosa. These lesions develop gradually and tend to persist indefinitely. Ultrastructural studies have revealed an increase in the size and number of mature melanosomes in basal keratinocytes and dermal melanophages, suggesting a functional alteration of melanocytes leading to increased production and transport of melanosomes.
The condition is benign and requires no treatment beyond regular monitoring. Differential diagnosis is crucial to distinguish it from other conditions that cause oral pigmentation, particularly PJS, due to the significant differences in prognosis and management.
External Factors That Create Dark Spots
A. Amalgam Tattoos from Dental Work
Amalgam tattoos are a common external cause of dark spots on the roof of the mouth. These occur when small particles of dental amalgam, commonly used in metal fillings, become embedded in the oral tissues during dental procedures. The result is a blue-gray or black permanent discoloration that appears as a flat spot. Unlike some other mouth discolorations, amalgam tattoos are harmless and don’t require treatment unless there’s concern about their appearance or a need to rule out other conditions.
B. Smoker’s Melanosis
Tobacco use, whether through smoking or chewing, is a significant cause of oral pigmentation. Smoker’s melanosis presents as brown or black patches on the roof of the mouth and other oral tissues. This occurs when tobacco stimulates melanocytes, the cells responsible for producing pigment, resulting in excess melanin production. The intensity of the discoloration often correlates with the duration and frequency of tobacco use. The good news is that smoker’s melanosis can gradually fade if the person quits using tobacco products, though complete resolution may take months or years.
C. Medication-Related Pigmentation
Several medications can cause pigmentation of the oral mucosa, including the roof of the mouth. Antibiotics like minocycline and doxycycline are known culprits, potentially binding to the proteins in the oral tissues and causing extrinsic staining. Other medications that may lead to oral pigmentation include antimalarial drugs, certain antipsychotics, and medications for high blood pressure. The discoloration from medication typically appears as blue, brown, or black patches and may be widespread throughout the mouth. Unlike some other causes of dark spots, medication-related pigmentation might persist as long as the medication is continued.
D. Black Hairy Tongue
Black hairy tongue is a temporary condition characterized by an abnormal coating on the tongue’s surface. Though it primarily affects the tongue rather than the roof of the mouth, it’s worth noting as a significant cause of oral discoloration. This condition develops when the small projections on the tongue (papillae) elongate and trap bacteria, yeast, tobacco, food, or other substances. These trapped particles can then become discolored, creating a dark, furry appearance.
Contributing factors include poor oral hygiene, excessive use of mouthwashes containing oxidizing agents like peroxide, medications that alter normal oral bacteria (particularly antibiotics), and dry mouth conditions. Tobacco use and excessive consumption of coffee or tea can also contribute to the development and severity of black hairy tongue. While alarming in appearance, this condition is generally harmless and can be resolved through improved oral hygiene practices, including regular brushing of the tongue and avoiding contributing factors.
Distinguishing Harmless Spots from Concerning Ones
Signs That Warrant Medical Attention
When examining black spots on the roof of the mouth, certain warning signs should prompt immediate medical consultation. Persistent spots that remain for more than two weeks require professional evaluation, as normal mucosal healing typically occurs within 10-14 days. Pain, bleeding, or ulceration associated with pigmented areas should be considered suspicious.
Changes in existing spots, such as rapid growth, irregular borders, or color variation, may indicate potentially malignant conditions. Additionally, spots accompanied by systemic symptoms like unexplained weight loss, fatigue, difficulty swallowing, or a chronic sore throat represent red flags requiring immediate attention.
Induration (increased tissue density) and fixation (lack of tissue mobility) are particularly concerning physical findings that might indicate malignancy. If pigmented spots are accompanied by neck masses or lymphadenopathy, this suggests possible spread of cancer and requires urgent medical evaluation.
Key Characteristics of Oral Cancer
Oral cancer often presents initially with subtle signs that may mimic benign conditions. Visual characteristics that distinguish potentially malignant lesions include:
- Appearance: Non-healing ulcers with raised, rolled edges and irregular margins
- Texture: Firm or indurated upon palpation, unlike the soft texture of benign lesions
- Color variation: May appear as white, red, or mixed white-red patches (leukoplakia, erythroplakia, or erythroleukoplakia)
- Location: High-risk sites include the lateral borders of the tongue, the floor of the mouth, and the soft palate
Erythroplakia (red patches) carries a significantly higher risk of malignancy than leukoplakia (white patches), with studies showing up to 90% of erythroplakic lesions harboring severe dysplasia or squamous cell carcinoma when biopsied.
Important clinical symptoms that may accompany oral cancer include neurosensory changes (numbness or tingling), tooth mobility without apparent cause, altered speech or swallowing, and persistent earache. Notably, pain is not a reliable indicator to differentiate between benign and malignant lesions, as early-stage oral cancers are often painless.
While tobacco and alcohol use are major risk factors, approximately 10% of oral cancers occur in patients without these traditional risk factors. Therefore, suspicious lesions warrant investigation regardless of risk factor status.
How Doctors Diagnose Pigmented Spots
Medical professionals employ various diagnostic approaches to evaluate concerning spots in the mouth. Initial assessment involves a comprehensive oral examination, including visual inspection and palpation of all oral surfaces and the neck to check for lymphadenopathy.
Diagnostic procedures commonly utilized include:
- Brush biopsy/scrape cytology: A minimally invasive technique to collect cells for microscopic examination
- Incisional biopsy: Removal of a small tissue sample for definitive histological diagnosis
- Imaging studies: CT scans, MRIs, or PET scans may be ordered to assess the extent of suspicious lesions and potential spread
For pigmented lesions specifically, doctors will determine if they can be wiped away, which might indicate conditions like oral candidosis rather than true pigmentation. Fixed pigmented areas may undergo dermoscopy or specialized oral examination with enhanced visualization techniques.
The definitive diagnosis of oral cancer requires histopathological examination. Biopsy results may reveal various findings ranging from benign conditions to dysplasia (mild, moderate, or severe) or invasive carcinoma. The degree of dysplasia helps predict malignant potential, with high-grade dysplasia carrying a greater risk for malignant transformation.
Early diagnosis significantly improves prognosis, as the 5-year survival rate for oral cancer remains around 50%, largely due to cases being diagnosed at advanced stages. Regular dental check-ups are therefore critical, as dentists are often the first healthcare providers to detect suspicious oral lesions.
Treatment Options for Mouth Pigmentation
A. When No Treatment Is Needed
Most oral pigmentations are benign and do not require specific treatment. Physiologic pigmentation, such as racial or ethnic pigmentation, is a normal variation that occurs due to increased melanocytic activity rather than an increase in melanocyte numbers. This type of pigmentation appears as flat, light to dark brown lesions that are evenly pigmented and bilaterally symmetrical, particularly in the attached gingiva. Since these are natural variations, no treatment is required.
Similarly, amalgam tattoos, which are the most common localized pigmented lesions of the oral mucosa affecting about 3.3% of the US adult population, require no treatment. These lesions result from amalgam particles embedded in oral tissues during dental procedures and appear as painless, blue, gray, or black macules. Since amalgam tattoos are only of cosmetic significance with no associated morbidity, the prognosis is excellent, and no intervention is necessary.
Oral melanotic macules, which are flat brown-to-black lesions caused by focal melanin deposition, also generally do not require treatment beyond monitoring. These benign lesions are among the most common pigmented lesions of the oral cavity.
Drug-induced oral pigmentation typically resolves once the causative medication is discontinued. In most cases, the discoloration fades within a few months after stopping the drug, and specific treatment is not required. Medications commonly associated with oral pigmentation include antimalarials, hormones, oral contraceptives, phenothiazines, and certain chemotherapeutics.
B. Medical Interventions for Cosmetic Concerns
When oral pigmentation causes cosmetic concerns, several interventions may be considered. For smoker’s melanosis, which is a reversible condition, smoking cessation is the treatment of choice. Studies have shown that smoking cessation results in a decrease in pigmentation, with prevalence similar to nonsmokers seen in patients who have quit the habit for at least 3 years.
For localized areas of hyperpigmentation that cause aesthetic concerns, surgical removal may be an option. Procedures such as excisional biopsy can serve both diagnostic and therapeutic purposes, especially for focal lesions like oral melanotic macules or melanocytic nevi. However, it’s important to note that surgical interventions are typically reserved for cases where cosmetic improvement is desired, not because of medical necessity.
Laser therapy has also been used for treating certain types of oral pigmentation with cosmetic concerns. For instance, Q-switched lasers have been employed in the management of certain types of oral pigmentation, although this is not frequently mentioned in the reference materials for the most common oral pigmentations.
C. Treating Underlying Causes
For pigmentations associated with systemic diseases, treatment should focus on the underlying condition. In Addison’s disease, for example, the insufficient production of adrenocortical hormones leads to increased ACTH levels, resulting in diffuse pigmentation on both cutaneous and oral surfaces. Treatment involves addressing the adrenocortical hormone deficiency, which will subsequently improve the oral pigmentation.
In cases of Peutz-Jeghers syndrome (PJS), which is characterized by intestinal hamartomatous polyps and mucocutaneous melanocytic macules, management includes surveillance for associated malignancies rather than specific treatment for the pigmentation itself. Patients with PJS should be educated about potential symptoms of intestinal obstruction and the need for cancer surveillance, as the syndrome is associated with a significantly increased risk of developing various types of cancer.
For oral melanoma, which is a rare but aggressive malignancy, early recognition and treatment are crucial. Surgical excision remains the primary treatment, with wide, clear margins essential for favorable outcomes. Adjuvant therapies such as immunotherapy and radiotherapy may also be employed, though they have shown limited success in treating advanced-stage melanoma. The prognosis for oral melanoma is relatively poor, with 5-year survival rates generally in the range of 10-25%.
Conclusion
Black spots on the roof of your mouth can stem from various sources, ranging from harmless pigmentation variations to symptoms of underlying medical conditions. Whether caused by genetic factors, external irritants like tobacco, or health issues such as oral melanosis, understanding the root cause is essential for proper treatment.
At Premiere Dental, we’re dedicated to offering complete oral care solutions that are customized to meet your specific requirements. Our team of skilled professionals can assist you with preventive care and treating oral health issues. Make an appointment with us right now to discuss your oral health issues and get rid of those painful black spots on the roof of your mouth.
