What Is Oral Thrush?
Candida is a naturally occurring microorganism found in the mouths of most people. Under normal circumstances, it exists in small numbers alongside other bacteria and fungi, kept in check by the immune system and the natural balance of the oral environment. Oral thrush develops when this balance is disturbed, allowing Candida to multiply beyond its usual levels.
The resulting infection — known clinically as oral candidiasis — typically presents as white or cream-coloured patches on the soft tissues of the mouth, though it may also cause widespread redness, discomfort, or a burning sensation. Thrush can develop when oral conditions change — for example, following a course of antibiotics, during periods of reduced saliva flow, or when the immune system is compromised.
While oral thrush can affect anyone, certain groups are more susceptible. It is generally not a serious condition in otherwise healthy individuals, but persistent or recurrent episodes may warrant further investigation to identify and address any underlying contributing factors.
Common Symptoms
The signs and symptoms of oral thrush can vary in severity. They may develop gradually and are sometimes noticed during routine self-examination or dental review:
White or Creamy Patches
Raised, white or cream-coloured patches may appear on the tongue, inner cheeks, roof of the mouth, or gums. These patches may sometimes be wiped away, revealing red or raw tissue beneath.
Red or Irritated Tissue
The tissue underneath or surrounding the white patches may appear red, inflamed, or sore. In some cases, redness may be present without prominent white patches.
Burning or Soreness
A burning sensation or general soreness in the mouth — particularly when eating or drinking — is a common feature of oral thrush. This discomfort may be diffuse or localised to affected areas.
Cracking at the Corners of the Mouth
Angular cheilitis — cracking, redness, or soreness at the corners of the mouth — may accompany oral thrush, particularly in denture wearers or those with reduced saliva flow.
Altered Taste
Some individuals notice a persistent unpleasant or metallic taste, or a general reduction in taste sensation. This typically improves as the oral environment returns to balance.
These symptoms may also be associated with other oral conditions. A professional examination can help distinguish oral thrush from other causes of white patches or mouth soreness.
Who May Be at Increased Risk?
While oral thrush can develop in anyone, certain factors may increase susceptibility by disrupting the natural balance of the oral environment:
Use of Inhaled Medications
Inhaled corticosteroids — commonly used in the management of respiratory conditions — can affect the balance of organisms in the mouth and increase susceptibility to oral thrush if the mouth is not rinsed after use.
Antibiotic Use
Antibiotics can disrupt the natural balance of microorganisms in the mouth by reducing bacteria that normally help keep Candida levels in check, potentially allowing fungal overgrowth.
Dry Mouth
Reduced saliva flow — whether caused by medication, mouth breathing, or other factors — diminishes the mouth’s natural ability to regulate microbial populations, creating conditions that favour Candida growth.
Denture Wearing
Dentures — particularly if ill-fitting, worn overnight, or not cleaned adequately — can create a warm, moist environment beneath the fitting surface that supports Candida accumulation.
Diabetes
Elevated blood sugar levels can affect the composition of saliva and the oral environment, potentially increasing susceptibility to fungal infections including oral thrush.
Reduced Immunity
Conditions or treatments that affect the immune system may reduce the body’s ability to control Candida populations, making oral thrush more likely to develop or recur.
The presence of one or more risk factors does not mean oral thrush will develop. Many people with these factors never experience symptoms.
The Role of Dental Assessment
A dental examination can play an important role in the assessment of oral thrush. During a clinical review, your dentist can visually inspect the oral tissues, noting the location, appearance, and extent of any patches or areas of inflammation. This helps determine whether the presentation is consistent with oral thrush or whether other conditions should be considered.
For denture wearers, the assessment may include evaluation of denture fit and hygiene, as ill-fitting or poorly maintained dentures are a recognised contributing factor. Your dentist can also review oral hygiene practices and assess whether dry mouth may be playing a role, offering tailored guidance to help manage these factors.
Where findings are consistent with oral thrush, your dentist can advise on next steps. In some cases, antifungal treatment may be required and can be obtained through appropriate medical channels. Your dentist will guide you on the most suitable pathway based on the assessment findings.
When Further Medical Advice May Be Appropriate
Mild oral thrush may resolve with supportive measures and attention to oral hygiene. However, there are circumstances in which further medical evaluation may be appropriate. These include situations where symptoms are persistent despite supportive care, where thrush recurs frequently, or where symptoms are particularly severe — for example, involving difficulty swallowing or significant pain.
Recurrent oral thrush may sometimes indicate an underlying condition that warrants further investigation. In such cases, a medical evaluation can help identify contributing factors that extend beyond the oral environment and ensure that appropriate management is in place.
Where medication is required to manage a confirmed case of oral thrush, it can be obtained through the appropriate medical pathway. Your dentist can advise on when this step may be beneficial based on the clinical findings.
Supporting Oral Health During Thrush
While professional assessment is recommended to evaluate oral thrush and guide management, the following supportive measures may help maintain oral comfort and contribute to a healthier oral environment:
- Maintain thorough oral hygiene, including gentle brushing of the tongue
- Clean dentures carefully each day and remove them at night to allow oral tissues to rest
- Rinse the mouth after using inhaled medications to help reduce residual deposits
- Stay well hydrated to support saliva production and a balanced oral environment
- Attend regular dental assessments so that changes in oral tissues can be monitored
- Avoid smoking, as tobacco use can disrupt the oral environment and increase susceptibility
These measures are supportive in nature and do not replace professional assessment or any treatment that may be recommended following a clinical review.
Professional Oral Examination for White Patches
White patches, persistent mouth soreness, or a burning sensation in the mouth should be assessed by a dental professional to determine whether oral thrush or another oral condition is present. A thorough clinical examination can help identify contributing factors and guide you toward the most appropriate next steps.
Your dentist may recommend a general dental examination to assess the oral tissues, a review of denture fit and hygiene if denture-related irritation is suspected, or an emergency dental assessment if symptoms are causing significant discomfort.
Oral examination for persistent mouth symptoms is available at our London clinics. You can attend our South Kensington dental clinic or our City of London clinic near St Paul's for a professional dental review.
