Oral manifestations of Scleroderma

Scleroderma can have a significant adverse effect upon the health of the mouth. A wide variety of different problems can arise that may result in increased liability to dental decay (caries), gingivitis and difficulty with dentures. Furthermore these oral problems, in particular xerostomia (mouth dryness) and microstomia (limited mouth opening) can reduce the quality of life of affected individuals.

Xerostomia
Xerostomia (oral dryness) can be a complication of scleroderma, specifically in those individuals with secondary Sjogren's syndrome (dry eyes (keratoconjunctivitis sicca), dry mouth (xerostomia) and a connective tissue disease, e.g. scleroderma and others). The oral dryness may also be worsened by the use of drugs such as antidepressants and antihypertensives which individually can also cause xerostomia. The resultant xerostomia causes dryness, and possible soreness, of the lining of the mouth (oral mucosa). In addition there is an increased liability to dental decay (caries), gum inflammation (gingivitis), possibly fungal infections (e.g. thrush) and loss of retention of the denture - particularly the upper denture. Patients with oral dryness may also have reduced or altered taste sensation, oral malodour (halitosis) and reduced quality of sleep.

Microstomia
Microstomia is probably the most significant oral consequence of scleroderma, giving rise to limited mouth opening, and as a result difficulty with eating and perhaps speech. The limited mouth opening can also make it difficult for affected individuals to insert and remove dentures and undergo routine dental care.

Other features
Some drugs used in the treatment of scleroderma may give rise to oral manifestations, for example gingival enlargement (e.g. calcium channel blockers). Telangiectasia (dilated blood vessels) can occur on the oral mucosa, lips and face. A number of skeletal changes about the face can also arise leading to loss of bone of the cheek bones (zygomatic arch) and lower jaw (mandible), although these are unlikely to give rise to symptoms. The skeletal changes are most likely in patients who have tightness of the facial skin.

Adverse side effects upon general oral health
Scleroderma can adversely affect oral health care. For example some patients may have mobility issues that prevent them from easily attending a dentist. Likewise systemic disease and multiple hospital appointments can limit attendance at a dentist. The increased liability to common dental disease (caries and gingivitis) may be worsened by any reduced manual dexterity such that it is difficult to maintain good oral hygiene. Finally the microstomia may make it difficult for patients to clean their mouths with toothbrushes and clean between the teeth (inter-dentally) with floss and related agents.

Maintenance of good oral health
While scleroderma can have a significant adverse effect upon the mouth, there are a number of strategies that can be undertaken by the patient and the health care professionals to lessen the adverse oral effects of scleroderma. These principally comprise lessening any xerostomia and ensuring the maintenance of a standard of oral hygiene that reduces any risk of dental decay and gum disease (the main causes of early loss of teeth and halitosis (gingivitis)).

Management of oral mucosal dryness
It is clearly important that patients avoid agents (for example alcohol and tobacco) that will worsen any existing oral dryness. Patients often attempt to substitute saliva by sipping water or non-sugary drinks. It is best, however, to avoid sugary agents as these will increase the risk of dental decay, and non-sugary drinks (e.g. fizzy drinks) give rise to mild chemical erosion of the outer surfaces of teeth.

A number of synthetic salivary substitutes are available as sprays and/or mouthwashes. These agents are mildly viscous, may contain fluoride and interestingly can be slightly acidic (and thus theoretically might increase the risk of dental erosion). There is no one particular salivary substitute that seems to be better than another - each patient has his or her own preference. Recently a mouthwash based upon an extract of linseed oil has been suggested to be of benefit in the treatment of xerostomia as it may reduce intra-oral plaque as well as lessen any xerostomia. There are, however, no studies of the effectiveness of this in patients with scleroderma.

A number of gels have been suggested to lessen oral dryness, in particular BioXtra® and Oral Balance®. These agents can be applied to any oral mucosal surface as often as the person so wishes, but again there is great variation as regards the benefit of this to each individual. It has, however, been suggested that Oral Balance® may reduce the burning sensation associated with oral dryness and also aid eating and swallowing. It may be possible to stimulate salivary flow. For example sucking sweets can cause some increase in salivary flow, but this increases the risk of dental decay. Diabetic sweets (which do not contain sucrose) can be helpful, but the sorbitol that is present in these products can cause gastrointestinal upset in some individuals. Chewing gum can be beneficial, but not all patients like this. Pilocarpine prescribed by doctors and dentists can specifically increase salivary function again, however, this agent has a number of adverse side effects, in particular gastrointestinal upset. Occasional patients receiving pilocarpine also report increased sweating.

As a consequence of the microstomia and oral dryness, some individuals with scleroderma find that their upper lip becomes adherent to the upper anterior teeth. It is possible to lessen this by applying a lubricating jelly (e.g. KY jelly®) to the inside of the lips and aspects of the upper teeth such that the lips glide over the teeth.

A wide variety of alternative agents have been suggested to be of benefit for the treatment of oral dryness associated with scleroderma and secondary Sjogren's syndrome, these include evening primrose oil, anhydrous crystalline maltose and dehydroepiandrosterone (DHEA). In general these agents appear to cause a slight improvement in oral dryness - if at all.

The dryness of the mouth associated with scleroderma reflects immunological destruction of the gland. Unfortunately no immuno -suppressant regime has been found to be effective in lessening or indeed reversing the inflammatory destruction of the glandular tissue. It is possible for corticosteroids to be injected down the ducts of the major salivary glands to reduce, albeit transiently, the oral dryness. Unfortunately this procedure would have to be repeated and therefore is of little clinical application. Most recently it has been suggested that gene therapy in which a virus, modified to allow local expression of proteins to enhance salivary flow, is injected within the ductal tissue. At present this method is in the early stages of development.

Prevention of dental decay and gingivitis
Patients with scleroderma are at increased risk of dental decay and gum disease as a consequence of the oral dryness and difficulty of mouth opening. It is important to lessen the risk of long-term consequences of these oral diseases (e.g. abscesses, extractions, tooth mobility and loss of teeth). A number of simple measures should be considered:

Diet
It is important that all patients (with or without scleroderma) have a diet that avoids frequent and/or excess sticky/sweet foods. These foods increase the accumulation of dental plaque and in turn increase the risk of dental decay. Savoury foods are much less likely than sugary ones to cause dental decay.

Tooth cleaning
Teeth should be cleaned at least twice daily. It is of course difficult for individuals with scleroderma to clean their teeth as a consequence of the poor mouth opening and fibrous nature of the linings of the mouth. It would thus seem best to use a toothbrush which has a small head with soft nylon bristles as this will allow the toothbrush to clean all parts of mouth. Handles of conventional toothbrushes can be modified to enable patients with reduced manual dexterity to easily hold the brush. Advice on appropriate modifications can be obtained from a dentist, hygienist or therapist. Electric toothbrushes do allow teeth to be cleaned very effectively, particularly as they have a small head, but some of them are slightly heavy due to them containing a battery within the handle. Toothpaste that contains fluoride should be used as this hardens the outer surfaces of the teeth. Additionally fluoride mouthwash (e.g. Fluoraguard®) used weekly or, better still, daily help harden up the outer surface of the teeth. Fluoride tablets are not of notable benefit to adults.

Inter-dental cleaning
Toothbrushing only cleans the outer surfaces of the teeth. Fluorides do not give rise to any adverse side effects - provided of course they are used correctly. It is important, if possible, to clean between the teeth (interdentally). Inter-dental cleaning can be undertaken using floss, of which there are many varieties, dental brushes or wood sticks. Electric flossers (e.g. Oral B Hummingbird) are also available. Wood sticks and inter-dental brushes should only be used where there are spaces between the teeth, as forcing brushes or sticks may result in trauma to the gingiva.

Gingivitis is lessened by the aforementioned toothcleaning methods. In addition regular use of antimicrobial mouthwash that contains chlorhexidine, triclosan or any other similar antimicrobial further reduce the risk of gingivitis. Chlorhexidine can give rise to staining of the teeth and can have an unpleasant taste, although the former may be reduced by using the mouthwash immediately following toothcleaning.

Oral malodour
Oral malodour can be lessened by keeping the mouth wet and maintaining good tooth cleaning. There is little evidence to suggest that tonguecleaning will improve oral malodour, but some individuals may find some benefit from this. Finally it may be possible to lessen oral malodour by using a specific mouthwash (e.g. Dentyl pH®).

Denture problems in scleroderma
Patients with microstomia can have difficulties in inserting and removing their dentures from the mouth. In addition the microstomia can make it difficult for impressions to be taken during the construction of dentures. These difficulties can be overcome by the construction of dentures that comprise 2 parts, thus allowing the appliance to easily pass into the mouth. Likewise impressions can be undertaken in sections.

Xerostomia can cause the upper denture to become easily dislodged. This can be lessened by placing synthetic saliva on the fitting surface of the denture. Osseo-integrated implants are a means of ensuring the retention of dentures. These are titanium screws that are placed within the jaw bones, the bone eventually uniting with the titanium of the implant. It is then possible to construct either dentures that clip onto the implant, or bridges that firmly attached to implants. There are no major contraindications to the placement of implants in patients with scleroderma, although it can be difficult to place implants in patients with severe microstomia. It must, however, be highlighted that implants are very expensive and Primary Care Trusts may be reluctant to fund such treatment.

Conclusion
Scleroderma has the potential to have a significant adverse effect upon the mouth, however, affected individuals are generally predisposed to the common diseases of the mouth - dental decay and gingivitis. It is important that all persons with scleroderma maintain an adequate standard of oral hygiene to lessen the risk of complications of such disease - particularly early tooth loss. Individuals with scleroderma are strongly advised to obtain appropriate specialist advice via their doctors or medical specialists.

The above article above has been written by Professor Stephen Porter
UCL Eastman Dental Institute

To download a booklet on Oral and Dental Aspects in Scleroderma click here
To download a leaflet on Dental Aspects of Scleroderma click here