EOSReport by Fiona Turner
79th Congress of the European Orthodontic Society - PragueJune 10th-14th 2003
Being over in the UK for 2003, the EOS congress seemed too good an opportunity to miss- especially as it was in the beautiful city of Prague. I had never been to Prague before and arrived to 30˚C, a tad warmer than Oxford.
The main themes of the congress were interceptive orthodontics, open bite malocclusions and the treatment of missing incisors.
Interceptive orthodontics was addressed initially by Professor William Proffit in the Sheldon Friel memorial lecture. He succinctly regarded the potential for growth modification in the three planes of space and the indications for treatment at other than the generally accepted treatment time. A continuing element of the interceptive orthodontics topic was the definitions of the terms effectiveness, efficiency and efficacy. Proffit reviewed the evidence on the timing of orthodontic treatment with regard to the effectiveness defined as the treatment response, the efficiency- the benefit: cost ratio (i.e. the burden of treatment) and efficacy- what changes occur. His points with regards to the major malocclusion groups can be summarised as:
Class I
- Serial extraction is effective for severe crowding but may or may not beefficient to be worth the extra time.
- There is no data to support early expansion in order to obtain better results.
- Maintain leeway space if crowding is moderate as this is efficient.
Class II-Two stage treatment is less efficient but is it more effective?
The indications for early Cl II treatment are:
- Special concerns-aesthetics/ bullying
trauma/ soft tissue issues
- Skeletal maturation ahead of dental maturation- girls
- Severe problems ? maybe or maybe not.
Class III
- The current trend is to treat the maxilla not the mandible.
- There is good data to support the use of maxillary face masks early- age 8 appears to be the ideal age, however, 20-25% will still require orthognathic surgery later.
The next talk was given by Lysle Johnston who almost had to walk out the auditorium exit as he had problems with his remote system. He discussed the means by which functional appliances achieve treatment results- not new information but it served to refocus and clarify the mechanism via the biological ratchet concept.
Camilla Tulloch, with a surprisingly English accent for all her years in the States, continued on the effectiveness, efficiency and efficacy theme presenting her group’s results. Not new material but clearly presented. She concluded that early treatment was not very efficient or effective.
Then in the traditional EOS format there were a series of shorter presentations touching on a variety of linked and unlinked material- overall they were of a good standard.
The afternoon’s keynote speaker was Professor Kevin O’Brien who spoke on the effectiveness of early Twinblock treatment. The results were from a multi-centre RCT. Points of interest were that 16% failed to complete treatment. Twenty seven percent of the change (which amounted to around 1.5mm) was deemed to be skeletal and 73% was dental (very similar to that of Camilla Tulloch’s study). Treatment had no effect on the amount of trauma experienced. Eighty percent required further treatment, therefore there was no apparent reduction in the need for further treatment. Psychological wellbeing was improved.
Other short but interesting presentations concluded the first day.
That evening the President’s reception was held in PragueCastleRoyalGardens. Despite the recommendation on the invitation to take an umbrella, since heavy rain showers are not uncommon in Prague in the summer evenings, it was a wonderful balmy evening. The castle, seat of the kings of Bohemia dating from the 14th Century is a pretty magical place. Being on a hill the grandiose gardens overlook the city & river. We dined on Czech specialities - no dumplings though - and sipped bubbles and some odd bright blue cocktail which I believe had some of the liqueur provided in our conference bags that we erroneously took to be mouthwash- evidently it wasn’t.
The next day started bright and early with Professor Proffit, the topic being the development of vertical problems. He summarised the skeletal basis of vertical problems as being the cranial base flexure, the orientation of the maxilla and the mandibular ramus length or gonial angle. Only the latter could be influenced environmentally. The eruption of the posterior occlusion is the most important aspect within the dental complex for vertical problem development. Proffit linked in equilibrium theory and was able to surmise that the tongue, lip and cheek pressures are more important than biting force, being of longer duration, for the development of the posterior occlusion. The tongue position at night is particularly important. He summarised treatment decisions at three time points.
a)Pre-adolescent- if the skeletal pattern is normal the open bite is probably caused by thumbsucking and will usually self correct.
b)Adolescent- control of the eruption of the posterior teeth is important.
c)Post-adolescent-Mild cases may be treated by elongation of anterior teeth.
Severe cases will most likely require orthognathic surgery, primarily by posterior impaction of the maxilla with a 90% chance of less than 2mm change.
Other short talks were given such as that by Everdi on the use of mini zygomatic implants.
Ram Nanda gave a keynote address on treatment of patients with high mandibular angles using a more posteriorly placed Nance type button known as a “Vertical Holding Appliance” VHA. This appliance was used to control the height of the upper 6’s sometimes in conjunction with a lingual arch to control the lower 6’s. He presented interesting but somewhat anecdotal cases of patients treated using the VHA.
Jan Artun presented material on the long-term prognosis of open-bite malocclusion and discussed the fact that the relapse often described is in A-P direction not inthe vertical direction.
Bjorn Zachrisson gave another slick rendition of the orthodontic regeneration of alveolar bone for use with implants. There was some new material but most we had already seen at the 2002 NZAO.
Vincent Kokich talked to a very specific issue, of overcoming the aesthetic challenges of implants in the maxillary lateral incisor region. His six key points were:
- Establishment of adequate implant space
- Don’t leave the roots too proximal
- Develop the implant site orthodontically
- Preserve the papilla during space opening
- Sequence gingival surgery prior to implant placement
- Always place implants after facial growth is complete
The rest of the program was made up of many unrelated talks. Of particular interest were those on the stimulation of bone cell differentiation using ultrasound and the effect of variation in tooth morphology on torque.
I did not attend the gala dinner as my husband and daughter arrived that day. I was, however, lucky enough to be able to stay on for a couple of days after the Congress to explore Prague with them. Prague is a beautiful city and there are a lot of tourists at the main sights but away from these areas it is possible to find some pretty special places like the old city walls at Vysehrad and the numerous wooded parks.