Orthodontics, the science of moving teeth, has progressed a long way over the last few years, with patients increasingly asking for straight teeth without years of wearing metal fixed appliances featuring unsightly, sharp wires and brackets, which are difficult to clean.

There are a number of innovations, which have attempted to address these problems, including ceramic fixed appliances, lingual appliances and clear aligners, which I will consider in turn.

1. Ceramic fixed appliances

These are tooth-coloured fixed appliances where the brackets cemented to the teeth are either ceramic or composite resin. The wires are generally metal with white coatings. These are tooth-coloured but bulky, difficult to clean around, the white coating on the wires is prone to chipping and the elastics discolour every month.

2. Lingual appliances

These are metal fixed appliances placed on the inside of the teeth allowing the teeth to be aligned without the braces being visible from the outside. They work well but can irritate the tongue and can be difficult to clean.

3. Clear aligners

These are a series of nearly invisible, clear plastic shells, which fit over the teeth and gradually move the teeth in small increments. They are removed for eating and toothbrushing/flossing. There are a number of competing clear aligner systems, but the best known and most technologically advanced is Invisalign (www.invisalign.co.uk). Invisalign was first developed in the late 1990s, with a fifth generation shortly to be released. It features state-of-the-art software called Clincheck, which enables each stage of the treatment to be visualised including any tooth-coloured attachments, which are used to help control the teeth for certain movements, and any tooth re-contouring to be done. Invisalign has been used to successfully treat over 2 million cases worldwide and has recently appeared in the news with a number of celebrities such as Chris Evans (with regular mentions on his radio 2 breakfast show), Justin Bieber and Cheryl Cole wearing them. Which should I choose? All of the systems have their advantages, and are not suitable for all cases so it is worth seeking an orthodontic opinion. Factors to consider include suitability, appearance, comfort and cleansability. In some cases it may be necessary to combine several different types of braces to achieve the ideal result.

What are the causes of bruxism and clenching?

There are many factors that can lead to grinding and clenching of teeth. It can often be a combination of factors such as missing teeth, over erupted teeth, heavily filled teeth, poor bite or stress.

What damage is caused by grinding and clenching of the teeth?

The teeth are generally only in contact when eating. Grinding and clenching means that there is much more contact of the teeth for long periods which lead to increased wear, increasing likelihood of fracture of the teeth and even loosening of the teeth if gum disease is present. If you have more complex fillings, veneers, crowns, bridges and implant retained crowns and bridges. Bruxism or clenching is more likely to cause early failure of these restorations. Headaches and Migraines are also associated with bruxism due to muscle tiredness and build up of muscle toxins.

What can we do to help with bruxism and clenching?

We can make a custom made night guard made of hard plastic which fits snugly on the teeth. It can either be worn on the lower or upper jaws. The night guard protects the teeth from grinding and clenching and can help stop it so the guard can be phased out.

Snoring is caused by a decrease in the muscle tone in the pharynx (throat) during sleep. This allows the throat wall to collapse in response to the reduced pressure in the throat when breathing in. The air flow becomes turbulent causing the sound that we recognise as snoring. This can sometimes become very loud causing disturbed sleep for partners and also embarrassment.

If you are overweight, regularly drinking alcohol, ageing, smoke or have enlarged tonsils these can all exacerbate snoring.

How many people suffer from snoring?

Snoring is very common; nearly half of all adults will snore at sometime during their sleep. 30% of adults and 60% of men over 60 years of age are habitual snorers. (Olson et al 1995)

Snoring is more common in men and post menopausal women due to the fat deposition around the upper body and neck. The prevalence of snoring in post menopausal women is similar to men. (Resta et al 2003, Orth et al 2007)

How can we help with snoring?

Dental appliances called Mandibular Repositioning Devices (MRD’s) which hold the lower jaw (mandible) in a protrusive (forward) position are very effective in reducing snoring.

The Somnowell MRD is adjustable by the patient, very robust and least bulky of the MRD’s.

somnowell.com

A silencer is made of a strong plastic which fits snugly over the upper and lower teeth and has interchangeable carbon fibre connecting bars.

These appliances are custom made to provide the best fit, comfort and reduced snoring possible.

  

Sleep apnoea is caused by the total closure of the pharyngeal (throat) wall due to the weakening of the pharyngeal wall allowing it to collapse during sleep. This can last for long periods causing reduced oxygen to the brain and body.  As the oxygen levels fall natural, protective mechanisms in the brain wake the patient up and so they start breathing again. This is call obstructive sleep apnoea. (OSA)

If you are overweight, smoking, drinking alcohol and ageing can exacerbate the problem.

How many people suffer from Obstructive sleep apnoea?

The prevalence of OSA in men is estimated to be 4% and in women 2%. As more people become overweight these figures are rising.

Can obstructive sleep apnoea be harmful?

OSA is linked with high blood pressure, strokes, heart attacks, acid reflux, diabetes and weight gain. Due to disturbed sleep, sufferers are more prone to have car accidents, not perform as well and generally feel more tired during the day.

How can we help with sleep apnoea?

Dental appliances called mandibular repositioning devices (MRDs) which hold the lower jaw (mandible) in a protrusive position are very effective in reducing effects of mild sleep apnoea.

For severe obtrusive sleep apnoea, the gold standard treatment is continuous positive airway pressue. (CPAP)

Loose dentures are often due to a lack of fit of the lower denture or imbalance in the biting pattern between the two dentures. As an upper denture is often the more stable of the two, it is the lower that gives way first and moves off the gum. This can cause soreness and ulcers under the denture and make eating and socialising a pain rather than the pleasure they should be. A loose denture can cause embarrassing moments and lead to a loss of self-confidence.

I would always look closely at the fit and function of your existing dentures to see if they can be improved, but the problem is more often solved by making a well fitting and balanced set of dentures using the BPS system (see blog on this).

In some cases even a well fitting lower denture may move in function, particularly if the teeth were lost long ago to leave a low ridge that limits retention of the denture. A lower denture relies to an extent on the wearer learning to use it and to control it with the tip and sides of the tongue. For many this is a struggle initially but can be overcome, but for some this is a difficult skill to master.

In the case of John who was about to lose his last few remaining lower teeth we could see that he was going to struggle to cope with a lower denture. He was happily wearing an upper denture and though worn it was comfortable and stable. His lower lip muscles were very strong and he had given up wearing the part lower denture made previously because he disliked the feel of it and its looseness, so he was dreading the thought of a full lower denture.

Our first step was to make a new well fitting and balanced set of dentures ready to be fitted on the day that we removed Johns’ last remaining lower teeth. This avoided any time without teeth and allowed us to see if John could cope, but as expected he struggled to tolerate them.

After two months waiting for the gums to heal we saw John again for a single surgical visit of an hour or so to place two dental implants approximately where his lower canine teeth used to be. Healing covers were placed on the implants which just showed above the gum and the lower denture was eased to fit comfortably over these.

After another two month wait for the implants to take to the bone we were able to make a copy of John’s new lower denture with Locator inserts in the denture directly over the implants. The healing covers were swapped for Locators onto which the denture now positively clicks into place.

This technique can also be used to improve the fit of troublesome upper dentures.

CEREC stands for Chairside Economical Restoration of Esthetic Ceramics, and is a state of the art digital system which enables the dentist to provide porcelain crowns, partial crowns, inlays, onlays, veneers and anterior bridges at a single visit.

It is the most used CAD/CAM system worldwide with over 28 million restorations placed since it was first developed in 1984. Cerec has been through a number of developments, which have widened its applications and made the restorations more lifelike. Studies have shown a longterm success rate of 95%.

How are they made?

The teeth are prepared in the usual way before the Cerec acquisition unit, a sophisticated 3D camera, is used to take a number of pictures of the prepared tooth and its neighbours. You can now sit back and relax while your dentist designs the restoration on the computer. The design is then transmitted to a milling machine which cuts the new restoration out of a solid block of ceramic. It is then finished, polished, stained and glazed. As little as 45 minutes later the restoration can be ready to be cemented in place.

What are they like?

Cerec restorations are entirely ceramic which means that they are metal free, avoiding the risk of visible dark lines around the edges of crowns as gums recede. The ceramic also allows a greater transmission of light through the restoration making it look more natural. The strength of the ceramic allows it to be used in thin section allowing the dentist to be more conservative, removing less tooth tissue.

Are all teeth suitable?

Most teeth are suitable, but there are certain situations where it is not the ideal option such as where there is insufficient space for the camera, the edges of the tooth cannot be accurately scanned or all ceramic is not ideal.

What are the advantages?

Natural, lifelike restorations are achieved at a single visit. They remove the need for messy impressions, plastic temporary crowns/veneers/bridges and a return visit for fitting.