by Mike Harrison, BDS, MScD, FDSRCS (Paed), Research Fellow in Paediatric Dentistry, Guy’s Dental Institute & The Institute of Child Health, London, England
Note: Dr. Harrison, along with colleague Evelyn C. Sheehy, is the co-author of a paper entitled “Dental Findings in Lowe Syndrome” which was recently published in Pediatric Dentistry (21:7, 1999), journal of the American Academy of Pediatric Dentistry.
The Paediatric Dentistry Department at Guy’s Hospital, London is a wonderful place. It’s not the staff, the facilities or the standards of care which make it so wonderful, but the view. Looking down from the 22nd floor of a high-rise hospital overlooking the River Thames, the whole of London is spread out in front of you in all its grimy smoggy glory. To be honest, children coming in to the clinic ruin the view-gazing for days at a stretch.
A few years ago, I was just watching the traffic stop for Tower Bridge to open, allowing a luxury cruise liner to slip gracefully through and moor alongside the Tower of London, feeling pretty content with the lot of a specialist paediatric dentist, when Conor came in. Within minutes I was completely out of my depth, and found myself receiving a very patient beginner’s seminar on Lowe syndrome from Conor’s mum.
His family doctor and dentist had been trying to find out why he had started to repeatedly put his fingers in his mouth, always on the same side. Was it ears, tonsils, teeth, gums? Conor wasn’t letting on, so we took up the guessing game where his doctor and dentist had left off.
His mum and I struck an unspoken deal. She would teach me about Lowe syndrome, and I would teach her about children’s mouths. Between us we determined we would get to the bottom of Conor’s finger-chewing.
One thing all hospital-based medical or dental specialists get rather heated up about is general practitioners not referring early enough. The way we see it, if we get to see uncommon problems often enough and early enough, we develop strategies and protocols (a word so “in” that it is rapidly becoming “out” in UK healthcare) based on experience. A generalist may see certain rare problems once in their entire practicing careers.
This is where the access issue raises its ugly head. Conor’s mum had every right to expect access to informed, sympathetic specialist care within the community where they lived. Specialists, however, expect people to come to them in their big university hospitals, even if it entails great inconvenience for patient and parent. The two sets of highly sprung double doors at the entrance to our clinic were the final access issue that Conor, buggy and mum were struggling with as I met them.
So what is so special about the mouth and teeth in Lowe syndrome? Lots, it seems, and around the world nobody is quite sure what the “typical” picture is. You should now rush to your back issues of On the Beam to read the results of the Lowe syndrome dental needs postal survey written by David Tesini (Fall 1999, p10). If you can relate your own experience to the majority of findings reported there, then you are part of the developing consensus view about what problems are commonly found.
Gum problems, plaque, loose teeth, and brushing battles
Let us start with gum problems, as these appear to be the most common feature in the mouth of somebody with Lowe syndrome. George Bernard Shaw allegedly took the view that “the professions are a conspiracy against the masses.” To this end dentists, taking their cue from the medics, give long and obscure names to parts of the anatomy or diseases for which there is a perfectly serviceable word in common speech.
Dentists will never talk about gums to each other. The mysterious word with which we cloak the pink cuff around every tooth is gingivae. When inflamed, it suffers gingivitis a painless and innocent itis in the greater scheme of things, and one which is probably present in all our mouths from adolescence onwards. Show me an adult who doesn’t have blood-reddened toothpaste or floss from at least one murky corner of their mouths, and I’ll bet they wear full dentures.
Gingivitis is caused by the accumulation of plaque (billions of wriggling bacteria which secrete their own sticky glue and a plethora of toxins). This is not to be confused with plague bacteria, which wiped out 40% of Europe’s population in the 16th century. A few weeks of diligent plaque control in the problem spots will usually stop the bleeding on brushing.
The ugly sister to gingivitis is the more destructive periodontitis. Teeth are held into the bone by a sheath of millions of fibres surrounding the roots the periodontal ligament. This is where that happy breed of dental specialists the periodontologists spend their days grubbing around. If a simple gingivitis is allowed to sit around for long enough, the toxins released by the plaque bacteria start to destroy the fibres of the periodontal ligament and also the bone surrounding the teeth. Eventually the teeth become loose as they have a decreasing amount of bone to anchor the roots. We do not become long in the tooth, rather, short in the gum, but somehow I don’t see the factually correct term catching on.
Individuals with Lowe syndrome seem to have great problems with periodontal disease, and this is probably for a variety of reasons. Firstly, getting in there with a brush can become a daily battle which, compared to some of the other battles to be fought, is one that is often too easy to surrender. It may be difficult to convince your neighbours that you are not pulling your child’s toenails out with red-hot pliers, but are in fact simply trying to get to his molars with a toothbrush. The gentle admonishment “we really aren’t managing to get to the posterior lingual gingival margins are we mum?” is the sole privilege of the dentist who doesn’t have to carry out the home oral hygiene care.
When it comes to toothbrush design, the turf wars are fought out on handle shape, which if the carer is carrying out the brushing, is probably an irrelevance. The answer lies in mediocrity — medium sized brush head, medium stiffness of bristles. Possibly the most important consideration is to frequently replace the brush when it develops a hippie-style centre parting is a sure sign that it is time to part company. One new brush design which really does seem to be a good idea is a triple-headed type, claiming to clean top and both sides of the teeth all at once. Ask your dentist if they have heard of it. If not, contact me for suppliers’ details.
Cysts and other dental problems in Lowe syndrome: a connective tissue issue?
It is possible that periodontal disease may be part of the Lowe syndrome phenotype (a recognised feature). The known genetic and metabolic defects in Lowe syndrome affect specific parts of connective tissue maintenance, and the millions of collagen fibres in the periodontal ligament are vital connective tissue components which need constant replacement to maintain health and function. Although this is only a hypothesis (mine in fact!), it would go some way to explain some of the other features of Lowe syndrome.
Many parents have reported in two postal surveys of dental problems in Lowe syndrome that late exfoliation or shedding of the first teeth is a real problem. The phrase most commonly used by parents is “double teeth,” describing the retained first teeth next to the newly erupted adult teeth. Whether this is due to a true connective tissue problem or due to the child simply not being willing or able to wiggle loose teeth out by himself is unclear.
The common report of cysts on the gum as teeth erupt or try to break through may also be part of the same connective tissue problem. A little sac of fluid surrounds every tooth while it is down in the jaw bone, and the sac (or follicle) usually ruptures easily as teething occurs. If this follicle does not break down, fluid accumulates, and a rather alarming swelling (cyst) develops. This is not infection. Surgery is rarely indicated, and it will usually pop by itself.
The next silly dental word to discuss is tartar. Neither a breed of fierce warrior swarming over the Mongolian steppes, nor a sauce to go with one’s fish ‘n chips. We dentists feel significantly aloof from the word to use a completely different one calculus for exactly the same stuff. When plaque is left in one place for a significant period of time, calcium and phosphate minerals floating around in the saliva precipitate out into the soft deposit, making it hard and crystalline. My London tap-water is so disgustingly mineral rich that an identical “scale” forms on the inside of my kettle, requiring me to bring my dental scaling instruments (those sharp pointy ones) home from time to time to give it a good going-over.
Adults usually get it accumulating on the back surfaces of our lower front teeth, an area rarely brushed, and the saliva pools there. The other location for this hard build-up is on the cheek surfaces of our upper molars. Mineral-rich saliva comes from big glands buried in the tissues of our cheeks, out through a small hole in the cheek lining, and deposits its minerals in any plaque you may have left on the cheek-surfaces of your molars. This is usually an adult phenomenon.
Children with Lowe syndrome may get an unusually troublesome build-up of tartar or calculus, possibly as a result of mineral supplements given to counteract chronic renal failure. Successful rickets prophylaxis may have the unwanted side-effect of excessive secretion of phosphates in the saliva, causing troublesome mineralized deposits in the mouth. The presence of calculus exacerbates periodontal breakdown, and the simple solution is to remove the deposits.
Did I say simple? Scaling may be a real problem for a child with Lowe syndrome, and occasionally impossible without sedating or fully anaesthetising a child. The latter step is a very difficult one to take, as periodontal disease is rarely painful, not life-threatening, and has no consequences other than hastening the loss of permanent teeth. The issue is really one of dignity. The mouth is an extremely expressive and sensitive area of our bodies, the cleanliness and health of which is, in my mind, equated with dignity of the individual. If your child is ever faced with the possibility of a general anaesthetic for dental care alone, the final decision can be made by you alone. Never be rushed into anything, and don’t be shy about asking questions.
Dental decay and the stuff we love (or need) to eat
The number one mystery dental word, and one that has been waiting in the wings until now is caries. This is our own hush-hush top-secret word for dental decay. I have never said the word to a parent, except to apologize for the use of an obscure language which they might hear muttered amongst us dentists.
Cariology ( knowing what rots teeth) is a mega-growth industry in the dental world. If I said Cola and candy are the prime movers and shakers in the rot-business, certain manufacturers would send the boys round to my house, so I will be less specific. The usual suspects admit it, you all know who they are are foods or drinks which contain refined sugars or carbohydrates. Plaque bacteria use these sugars for food, and excrete a whole heap of waste products, some of which are acidic. Acid does to teeth what it does to everything else: it dissolves them. After we have eaten something sweet, our teeth are treated to an acid bath for over an hour afterwards. The more often the acid attack, the more mineral is dissolved out of the enamel of the teeth.
Eventually the enamel, which is like the glaze on a plate, caves in, and it’s party time for the bacteria. They get to work on the dentine underneath until the nerve (yes, we call it something different, the pulp) is reached. Having experienced both, my wife insists that she would rather have drug-free childbirth than toothache. The irony is that teeth don’t actually need a nerve inside them — it is just a design fault — but boy do we pay for that unnecessary bit of flesh inside our pearlies.
Children with Lowe syndrome may be less prone to caries than others. The make-up of their saliva and oral environment may be responsible for this. Neutral sodium phosphate supplements, along with excessive urea excretion in chronic renal failure may have the fortuitous effect of buffering or neutralizing acids produced by plaque bacteria.
One lesson learned by most paediatric dentists who work with children with multiple medical problems is that all our carefully rehearsed scripts about dietary control go out of the window. If a renal physician or pediatrician is suggesting a particular diet, then it is for good reason. Failure to thrive and poor weight-gain are serious threats to a child’s wellbeing. I for one always take a back seat, endorse whatever diet is required to promote weight gain, and adopt a fall-back strategy of dental damage-limitation.
One weapon in our armamenentarium for the decay-prone child is fluoride supplements. While most toothpastes contain small amounts of fluoride, professionally applied fluoride at higher concentration may help to re-mineralize enamel which is subject to frequent acid attacks.
Paediatric dentists vs. boys with Lowe syndrome
Above all else, one of the major barriers to dental care for the child with Lowe syndrome is that of behavior management. This is something that specialist paediatric dentists think we do better than any of our toothy colleagues. However, the specific behavior patterns in Lowe syndrome throw down the gauntlet to our tricks and strategies. In my mind, physical restraint is not a technique of behavior management; it is verging on common assault.
BUT (big big big BUT), if the restraint is not injurious, is for the main part carried out by a willing parent, and the dental treatment involves more-than-adequate pain control, then the crude approach may allow some simple work, such as scaling, to be carried out quickly and effectively without recourse to pharmacological methods of behavior management. Many other strategies are worth a try, particularly systematic desensitisation, which is posh for letting a child get used to something a technique which you probably use every day.
About parents, the need for more research, and London daydreams
As for Conor’s repetitive finger-chewing, we never did get to the bottom of it. But how easy is it to dismiss this kind of thing as typical of the obsessive repetitive behavior sometimes seen in Lowe syndrome? For many children with learning difficulties, fingers in the mouth are indicative of oral pain, and is a sign which must be taken seriously and thoroughly investigated. Recently I have met more children with Lowe syndrome, and the one thing which they do seem to have in common is the dedication of their parents to all aspects of their life and care. I am deeply humbled, and feel utterly helpless when I am left apologizing for not knowing why something is happening in a child’s mouth.
“More research is needed” is the traditional rallying cry of the specialist with an academic bent. While research can sometimes be a self-fulfilling indulgence with no direct practical application, there is a lot to be said for knowing as much as possible about as much as possible. If the result is knowing what to expect, why it occurs, and then how to treat or prevent it, I strongly urge you to consider joining in with your child the next time somebody asks you to take part in a research project concerning Lowe syndrome. You never know, it may be me asking, if I can ever tear myself away from the panoramic view from my office window.
Oh, and by the way, if you ever come to London, and are in my neighbourhood, don’t bother asking me directions to London Bridge you will get the snotty reply that some yank bought it a few years back and moved it all brick-by-brick to some desert or another in the US. But look, Tower Bridge is opening again as I write, so I will let the patients’ struggles with the spring-loaded double doors continue unaided whilst my daydreams follow the luxury liner up the Thames.
If you are more interested in the whys and wherefores of pediatric dentistry, I strongly recommend the website of the American Academy of Paediatric Dentistry www.aapd.org, particularly their publications section. You are also welcome to contact me by e-mail at firstname.lastname@example.org.