Introduction

Torus palatinus (TP), also known as maxillary palatal torus, is a benign bony tumour of the maxilla which protrudes from the middle of the roof of the mouth (the hard palate). TP is generally asymptomatic, and people do not usually notice it until they are detected incidentally during dental check-ups. It is a natural physiological variation in some people that grows slowly over time. TP does not usually require any treatment unless they are causing problems like discomfort, or interference with dental prostheses.¹ 

A good understanding of the epidemiology of torus palatinus, including its aetiology, demography and prevalence, is paramount for physicians to provide accurate diagnosis and management strategies that will improve patient care. This article explores the prevalence of TP in different populations with a focus on demographic factors such as age, sex, ethnicity, and geographical location. It also delves into associated genetic, developmental and environmental factors contributing to the epidemiology of TP.

Anatomical and clinical overview of torus palatinus

Torus palatinus is a bony outgrowth at the midline of the roof of the mouth. It is a common form of benign exostosis, an abnormal bone formation that protrudes from a surface. The exact cause of TP remains undefined and unclear, although many hypotheses suggest the role of genetic, environmental, or dietary factors.^1,2

Anatomical presentation

TP presents in various forms and can be described as flat, lobulated (lumpy), nodular, or irregular. The mass is covered with mucus, and often appears pale due to reduced blood flow. It is sensitive and becomes ulcerated and inflamed when injured.¹

People with torus palatinus may experience symptoms like:

• Bony mass on the roof of the mouth
• Speech impediment
• Painless lumps on the roof of the mouth
• Difficulty fitting mouthguards and braces properly
• Difficulty placing dentures on the roof of the mouth
• Food getting stuck around the edges of the growth
• Difficulty swallowing
• Difficulty chewing¹

Aetiology 

Genetic predisposition

Genetic factors play a significant role in the development of TP. Studies show that it is a common factor in the development of TP. Research on familial patterns reports that people with a family history of torus palatinus have a higher chance of developing the condition.^1,3

Mastication mechanical stress

It has been hypothesised that mechanical stress exerted by the biomechanical force of chewing can promote the growth of bone on the palate. The formation of the bony mass is a coping mechanism that the body uses to adapt to stress, especially in individuals with diets containing large amounts of calcium and unsaturated fats.¹ 

Studies also suggest that TP may occur due to small injuries, especially in people with abraded teeth (worn-down teeth), which could be from habits like grinding your teeth or chewing too hard. These bony exostoses may develop as a reaction to how you strain your mouth or jaw.⁴

Environmental factors

Although genetic factors play a role in the development of TP, environmental factors also contributes to its development.^1,2 Studies show that dietary habits, especially the consumption of food rich in vitamin D and polyunsaturated fats, contribute to the formation of bony exostoses.²

Prevalence of torus palatinus

The prevalence of TP has been the subject of many studies in epidemiology. There are notable differences in the reported studies on the prevalence of TP across populations. 

The global prevalence of TP ranges from as low as 2% to as high as 67%, depending on the geographical region, method used to conduct the study, and ethnic composition of the study group.⁴

Global prevalence

Ethnicity influences the prevalence of TP. Studies have consistently reported Asian populations to have the highest rates. The prevalence of TP in Asians is above 20%, while that of Africans is above 10%. Europeans have a prevalence of TP between 10-20%.⁴ Studies show that Jordanians have a prevalence rate of 29.8% with Caucasians generally having a lower prevalence rate than Mongoloids.²

Age distribution

Torus palatinus is commonly detected in early adulthood or adolescence, with a higher prevalence among adults than children. The palate continues to develop in children, and as they become older, TP frequently becomes more noticeable. This contributes to the gradual growth of TP over time and its detection in older adults, at which point it has become clinically significant.⁵

Gender differences

Many epidemiological studies have reported gender differences in the prevalence of TP. Across various population groups, there is a higher prevalence of TP in people assigned female at birth (AFAB) than in people assigned male at birth (AMAB). For example, a study conducted with multi-ethnic groups reported that the combined prevalence of TP in people AFAB was 23% compared to just 6% in people AMAB.⁴ 

Though the reason for the higher prevalence of TP in people AFAB compared to those AMAB is not fully understood, some studies suggest that the X chromosomes may play a role. Since people AFAB have two X chromosomes while those AMAB only have one, this difference might help explain why TP is more common in people AFAB.² 

Some studies suggest that hormonal changes, such as those that occur during periods or postmenopause, could potentially influence bone metabolism. These changes could potentially contribute to the formation of bony growths like TP in people AFAB.⁶ 

Does geographical distribution contribute to the prevalence of TP?

Geographical location plays a role in the prevalence of torus palatinus. Higher prevalence of TP is reported in some regions with higher concentrations of specific ethnic groups like Asia. Meanwhile Europe, which has a large Western population, has a lower prevalence. In the African population, TP is also found to be less common.⁴

Does culture influence the development of TP?

In certain groups, torus palatinus is believed to emerge as a result of cultural behaviours, especially eating habits. According to a study, higher levels of vitamin D and polyunsaturated fats may occur in people who eat saltwater fish in Norway. These micronutrients are linked to bone formation and may increase the incidence of TP.²

FAQs

Does torus palatinus have any influence on dental practice?

Yes, the presence of TP in the buccal cavity can impact the practice of prosthodontics and restorative dentistry. Dentists are encouraged to check for TP during dental examinations and should consider its presence when preparing for procedures requiring dental prosthetics like dentures or dental implants. 

What are the complications associated with torus palatinus?

The most common complication associated with TP is its interference with dental prosthetics like dentures. A suitable fit for dental appliances may be difficult to achieve due to the bony protrusion, leading to discomfort or the need for surgical removal of TP. Other complications include bad breath when food gets stuck on the growth, difficulty brushing the teeth properly, continuous trauma when eating, interference with the positioning of the tongue, and closing the mouth properly.

Can torus palatinus be treated?

TP is asymptomatic and harmless. However, surgical removal can be recommended by your dentist if it disrupts dental procedures like fixing dentures, or if it causes excessive discomfort.

What is the recovery time for torus palatinus surgery?

It takes up to 4 weeks to fully recover after torus palatinus surgery. 

Can it develop again after removal?

In rare cases, TP can grow back after surgery if the underlying genetic, environmental, and mechanical factors which caused it are still present.

Is torus palatinus cancerous?

No, TP is not cancerous. It is a benign bony growth on the roof of the mouth.

Can torus palatinus get infected?

Due to repeated trauma during eating and chewing, the mass can get ulcerated. This injury can be slow to heal due to poor blood supply to the surface. This can predispose it to infections, especially if there is poor oral hygiene. 

Can the presence of TP cause snoring?

TP is not the primary cause of snoring. However, larger ones can contribute to snoring by causing the narrowing of the airways in the roof of the mouth when combined with other factors responsible for snoring.

Summary 

Torus palatinus (TP) is a benign buccal exostosis which occurs as a bony outgrowth at the midline of the hard palate. It is asymptomatic and is typically discovered during regular dental examinations. It varies in size and shape, ranging from flat to lobulated, nodular, or irregular shapes that may complicate dental prosthetic procedures and surgeries. Despite being benign, TP has clinical relevance, especially in dentistry, where it can cause difficulties during oral surgical treatments and impede prosthesis rehabilitation.

A good understanding of the aetiological factors, demographic studies and prevalence of TP is important for providing appropriate diagnostic accuracy and patient care in populations where the condition is more prevalent. Genetic factors, environmental factors, ethnicity, age, gender, geographical location, and dietary behaviours all play a significant role in the development and distribution of TP.