The evolution of support systems for fixed functional appliances (FFA) is, in my opinion, a backward step in the scientific and technological progress that is foreseen for the next century. Evolution demonstrates that initially, appliances were supported on bands, then came the use of rigid bands, connections welded to the bands, the introduction of crowns on the upper molars and then on all molars and sometimes on the lower pre-molars. The introduction of the cantilever increased the thickness of the wires that were being used as means of support. Too much time was spent fitting crowns, cementing, waiting in the lab, removing the appliance for repairs and refitting and recementing bands for finishing. This is a highly uncomfortable experience for the patient.
In my 9 years of experience with the Ritto Appliance, I have discovered that this is not the functional philosophy for the next century. In addition to considerable time lost in the laboratory time, with its inherent costs, it also means a loss of total treatment time and discomfort for the patient.
In order to avoid breakage problems and unwanted dental movements, and to be successful with the treatment, it is extremely important to prepare the patient and stimulate the musculature with the mini splint before fitting the FFAs. This can be achieved in 6 weeks.
Many orthodontists may have experienced the frustration of continual breakage which discourages the use of FFAs.
In functional treatment with a FFA, it is necessary to prepare the patient for 1 to 2 months before fitting the appliance so as to stimulate musculature and avoid the patient exerting too much force on the support systems, fracturing them or originating unwanted dental movement. For this reason, the use of a mini stimulator for mandibular advance is advised. This is a thermoformed splint of 0.7 mm in thickness, only for the upper incisors and incorporates an acrylic bite block for the lower incisors constructed with the mandible in a forward position.
For the first 15 days or 1 month, the patient should wear the splint for as long as possible and maintain the lower incisors fitted into the Bite block. In the following weeks, the patient should start to carry out swallowing exercises with lips in contact and with incisors against the bite block.
Only after this stage should therapy be started with the Ritto Appliance, given that the musculature has already been stimulated and the patient has memorized the forward position of the mandible. Deblocking of the occlusion is also achieved.
Making retentions on the distal gengival area of the teeth 12 and 22. Normally this is enough to achieve good retention. When there are spaces between the upper incisors, an internal clasp is a solution for additional retention (see ahead).
Thermoformed splint of 0.7 mm in thickness, only for the upper incisors, made in a Biostar machine.
Bite block for the lower incisors constructed with the mandible in a forward position. For additional retention I advise an internal clasp.
It is possible to fit the Ritto appliance in conjunction with the mini stimulator for the first few weeks. It can be fitted with brackets on the upper incisors.
Another important factor that contributes to comfort and rapid patient adaptation is the achievement of posterior contact after the advance of the mandible. This also creates a posterior proprioceptive sensibility. It is not always necessary to have perfect co-ordination of the arches before starting functional treatment. Sometimes, even with a pronounced Spee curve, therapy can be started as long as some artificial contacts are constructed with composit on the molars. The extrusion of the premolars can be beneficial in the correction of a vertical problem.
Artificial contacts constructed with composit on the lower molars in a case with a severe curve of Spee, to achieve posterior contacts and stability.
A clinical case of Class II div. 1 with the mandible in a forward position (Class I) when the patient put the lower incisors against the bite block. The same patient using the mini stimulator and the Ritto Appliance. This helps the patient to memorize the new position of the mandible during the first week with the Fixed Functional Appliance.