Parkinson's disease and oral health care
The following are observations on more than 100 people with Parkinson's disease (PD), at the New York University, New York City Medical Centre Faculty Practice, over 3 years.
Dental and oral hygiene
The preliminary findings of dental and related problems suggest that there is an urgent need for more specific oral and dental treatment for people with PD.
In the following findings, recommendations for dental care are discussed.
Findings
- There is an increase in dental cavities and accumulation of dental plaque, associated with a marked increase in gum inflammation and periodontal disease, overt tooth mobility and pain. In part, this is due to reduction of hand-to-mouth mobility in PD and the loss of skill of tooth-brushing.
- When people wear removable partial or complete dentures for a long time, the fit of these prostheses can be poor and usually there is a loss of bite stability. Accordingly, the dentures generally have inappropriate chewing contacts when the upper and lower teeth bite against each other. This irregular bite loosens the fit of the dentures, can break both natural and artificial teeth, and often causes ulceration and pain in the supportive gum tissue.
Treatment
For these primary concerns of dental and oral health, the following treatment is recommended.
- Regular dental examinations at least twice a year to find and treat dental cavities, plaque accumulation, gingi-val and periodontal disease, 'bad bite', missing teeth, defective bridges and breakdown of restorations.
- Oral prophylaxis (preventive care) every 6 months or if necessary every 3 months. A dentist or dental hygienist should provide oral prophylaxis and a home-care regime.
- Clear instructions and demonstrations of home oral hygiene are essential. This includes information about choice of toothpaste, tooth-brushing, dental flossing, mouth rinses and saliva control. There are electric toothbrushes and electronic devices available, all useful for people with limited hand skills.
- When people are in an advanced stage of PD it is important to have a care-giver (partner, child, aide, nurse) assume responsibility for oral hygiene on a daily and regular basis. The dentist should give thorough advice to this care-giver and follow up the care during professional clinic visits. The care-giver should also be instructed to wear gloves, and told how to maintain an infection-free environment.
- When people cannot go to a dentist's office, it may be possible to arrange limited home dental care by a private dentist.
- Dental care treatment options for people with PD should be aimed at maximising oral health and function. This reduces the risk of needing extensive maintenance as the person's physical condition deteriorates and their oral hygiene and access to dental care become difficult. The care also includes cancer screening and review of other oral functions and their oral hygiene.
Quality of life and dental care
The quality-of-life issues related to the need for dental care described above are those oral functions which in part are essential for a healthier lifestyle for people with PD. They are:
- disorders of swallowing;
- disorders of nutrition;
- disorders of language and communication;
- loss of self esteem;
- impairment of job and vocational function; and
- impairment of social communication.
Disorders of swallowing
Swallowing difficulties may relate to any of the 3 stages of the swallowing process that takes place sequentially in 3 chambers.
Stage 1. The mouth
The mouth and teeth compose the first chamber. The act of swallowing is initiated by the closure of the lips after chewing and preparation of food. When the lips close, the food is propelled backwards toward the throat by pressure of the tongue tip against the hard palate and the teeth. The food at this stage is at the person's voluntary control. If the food particles are perceived as too large, the food can be chewed further; if the food is too dry, it can be moistened with either saliva or more fluid such as water or an artificial moistener fluid.
It is during the first stage of swallowing that dental care can be most effective in assisting swallowing. If the lip and face muscles are weak because of the disease, or if food cannot be chewed adequately because teeth are missing, dental care can both strengthen the lip action and restore chewing efficiency so that food particles can be prepared for swallowing.
Another factor in swallowing difficulty is pain caused by inflamed dental pulp and gum tissues. Pain caused by pressure on the teeth or by hot or cold foods can cause difficulties in swallowing. The dentist can always relieve pain caused by gum inflammation, decayed teeth, faulty fillings, crowns, dental bridges or removable dentures.
The final consideration in the mouth and facial part of the swallowing process is the stability of the bite when the opposing teeth close together during chewing. This preparation for swallowing is all voluntary and usually dependent on intact teeth, or their replacement, to be most effective. When teeth are missing or faulty, the tongue becomes a more dominant swallowing agent. In these cases the tongue braces the jaws for swallowing by being pushed between the opposing jaws. This abnormal swallowing pattern requires a more fluid and softer diet.
Stage 2. The pharyngeal chamber
When food is passed into the throat, the lower jaw must be fixed in position (stabilised) so the floor of the mouth can be elevated. This allows the laryngeal valve (vocal folds) to be closed, preventing food from being aspirated into the lungs. Associated with the elevation or tucking forward of the larynx is the control over head posture.
It is advisable for people with PD to sit upright when eating so that gravity does not cause food to pass into the pharynx before one is ready to initiate the second phase of swallowing. People should not eat or drink lying on their backs. If people are bedridden, they should drink lying on their sides with the head elevated as high as possible.
Another factor is that it is normal to swallow up to 2,000 times a day, which makes it a full-time activity during the waking day. Since many people with PD salivate excessively, they should sit forward when watching TV for a long period of time. A pillow behind the back to move the trunk forward when they have to swallow usually facilitates this function. Aspiration of saliva into the larynx and lungs can cause coughing spasms which sometimes are very debilitating. It is also advisable not to speak when chewing or swallowing, since doing several things at once is difficult for people with PD.
The second phase of swallowing is under only partial voluntary control, so the precautions about type of fluid, body posture and healthy teeth are essential for effective swallowing.
Stage 3. The oesophagus
In this stage food passes from the oesophagus to the stomach; the third stage of swallowing relates to the oesophagus and its upper valve, from pharynx to oesophagus, and the lower valve from the oesophagus to the stomach. When these valves don't function properly, reflux or regurgitation of gastric fluid can cause heartburn.
Difficulty with this part of swallowing is a medical problem and should be investigated by a physician or speech pathologist. Some hospitals have a swallowing clinic to assist people with the second and third phase of swallowing disorders.
In summary
Healthy teeth and gums and controlled posture can provide an effective swallowing function for people with swallowing disorders. Sometimes a speech pathologist trained in oral and dental aspects of swallowing co-operates with the dentist to improve and maintain effective swallowing.
Disorders of nutrition
Nutritional deficiency may occur with progressive loss of motor skills and diminished dental health care in people with PD.
As PD progresses, or if the teeth are defective, food intake may become a problem. People may no longer be able to eat the foods they prefer. Since protein and other dietary requirements are altered as the disease progresses, it is essential that dental health be considered a major factor in nutritional management for people with PD. Their physician and dietitian should inquire into their dental health status and make the appropriate referral to their own dentist. If they do not feel experienced enough about treating people with movement disorders like PD, they may contact the Australian Dental Association or local government dental clinic.
Disorders of speech and language
Speech impairment often accompanies PD. It has been estimated that 70 per cent of people with PD show signs of speech impairment but that only 5 per cent receive speech therapy. One of the main contributing factors to speech problems is poor dental health, especially loose teeth, missing teeth and defective dentures.
The teeth are the principal skeletal support for the pronunciation of many consonant sounds (e.g. labials like F and V, lingual dental sounds like T, D, R and L, and continuant sounds like S, Th and Ch). When the anterior teeth are missing or defective, the absence or distortion of these consonants causes speech to be less intelligible. In people with PD whose muscle movements are unco-ordinated, the speech may be totally incoherent.
When dentures are ill-fitting, their looseness distorts not only the consonants but also the vowel sounds, making the person fearful of speaking. This looseness and anxiety magnifies the speech difficulty. People with PD often reduce their breathing energy and their speech becomes inaudible. Appropriate bite allows more effective diaphragmatic breathing to give a supportive breath stream for speech. Furthermore, when dentures are loose many people with PD who salivate excessively cannot swallow their saliva effectively, and either drool or spray their saliva when attempting to talk.
Faulty breathing patterns also prevent a long enough stream of air to be exhaled when a person is speaking. The breathing patterns have to be co-ordinated with an appropriate head and jaw posture for speech. A dentist can check the bite to see if it prevents or assists in proper air exhalation and inspiration for speech.
Faulty tooth alignments and gross irregularity of bite between the upper and lower jaws cause poor lip approximation to produce faulty labial sounds like P and B.
Associated with lip difficulties in speech is the distortion of lip form which causes excessive creasing and folding of the muscles around the mouth and lips. Routine dental examination, tooth replacement, denture repairs and properly restored teeth will improve speech.
Loss of self esteem
The impairment of speech, coupled with changes in facial contour and salivary drool, often undermines the self-esteem and self-image of people with PD. They often choose to eat alone and thereby avoid embarrassment. One of the more critical aspects is the effect on their psychosexual feelings. They often feel their general disability makes them less desirable as a connubial partner. This feeling of inadequacy is heightened where the face and lips are distorted, and when the teeth are decayed or filled with plaque and gums bleed easily. Appropriate and sustained dental care and prophylaxis may alleviate the stress on their libido and sex drive.
Job and vocational status
Many people with PD are still employed in a wide variety of vocations. Often their ability to continue gainful employment depends on their oral and facial appearance and their ability to communicate. Dental care to improve their appearance and speech and diminish salivary drool may be a critical factor in continued employment. A dentist, often in co-operation with other professional associates, can solve these problems.
Socialisation and community activity
People with PD often become dependent on their care-givers. They tend to withdraw, eat alone and become socially isolated. Caring for their facial and oral needs often facilitates and/or improves socialisation. Improving the arrangement of teeth, cleaning the gums of plaque and stains and replacing missing teeth and dentures give people more confidence to socialise and to be a part of community activity.
Summary
People in all stages of PD can play an active role in maintaining or improving their oral and dental health, and also in an oral cancer-screening programme. The following steps are essential.
- Regular oral hygiene by a dentist or hygienist at least every 6 months.
- Regular periodic dental examination at least every 6 to 12 months if oral hygiene is maintained.
- Use of special-handle toothbrushes to facilitate hand grasp.
- Training in home care for care-givers in advanced cases.
- Monitoring of changes in oral function such as changes in speech, swallowing or nutritional habits.
Home care, if necessary, for both emergency and routine care for home-bound people may also be available.
Choosing a dentist
Many dentists are not equipped professionally or psychologically to treat people with moderate to severe PD. If you desire assistance, you may contact the Australian Dental Association, or your local Dental Service Clinic listed under 'Dental' in the telephone book. These clinics can only see eligible patients and can refer as required to the Dental Hospital.
Acknowledgements:
Sidney I. Silverman, D.D.S., Clinical Professor of Neurology, Clinical Professor of Restorative and Prosthodontic Dentistry, NYU Medical Centre, New York City, NY.Originally published as an Educational Supplement by the American Parkinson's Disease Association Inc., 1250 Hylan Boulevard, Staten Island, NY 10305. Copyright 1996. Reprinted and adapted for Australia with permission.
Last Reviewed: 23 July 2002
