For most people, a dental check-up per year is adequate. However, for those with high risk or special needs, a dental check-up every six months may be necessary. People with high risk or of special needs include:

Mentally handicapped individuals
Mentally handicapped individuals may have difficulties in maintaining a basic level of oral hygiene. They are very prone to Periodontal Disease and Dental Caries.

Patients who have received radiotherapy in the head and neck region
In the process of radiotherapy, normal oral tissues are affected. The treatment may give rise to a decrease in saliva secretion and inflammation of the oral mucosa, which may lead to Dental Caries and Periodontal Disease.

Smokers
The chance of developing Periodontal Disease of smokers is five times higher than that of non-smokers.

Patients with disabling oral diseases
The patients with oral tumour or cleft palate need to have frequent oral examination to maintain their oral health.

Patients with Systemic diseases
The immunity systems of patients with Diabetes Mellitus, Haemophilia or AIDS are compromised, leading to a lowered body resistance to bacterial infections. If their oral hygiene is poor, the dental plaque accumulated on the tooth surfaces will easily give rise to Periodontal Disease and the disease will then progress rapidly.