Invisible orthodontics

Spaces open through the Active Retainers use

Dr. Anna Mariniello

Dr. Fabio Cozzolino

Dr. Giuseppe Cozzolino

In case of dental crowding an alignment can be made, with or without stripping, by using pre-activated retainers. Lingual orthodontics without attacks has been originally created by Dr. Aldo Macchi and Dr. Nunzio Cirulli and has also been successfully performed by other authors. This innovative technique is based on the use of retainers constituted by 5 interweaved wires of 0.0175 inches thick, shaped and activated in order to obtain the desired dental movements. Active retainers, similarly to the passive ones, are bonded on the lingual surface of the teeth. Therefore, there are invisible and they represent an ideal treatment for all patients that don’t favor the classic orthodontic therapy. Moreover, active retainers are very thin and more comfortable compared to the smaller lingual attacks. They don't induce phonetic changes even in the first days of therapy. Thanks to all these characteristics, active retainers are actually more and more requested.

With the active retainers technique all malocclusion types may be solved: first class malocclusion with dental-basal discords, in excess or in fault, and II or III class more complex malocclusions for the latter, we also use other invisible devices such as micro screws).

Now, let's see how it can be possible treating dental crowding with the use of active retainers. In case of a minimum dental crowding, with an inter-proximal surface overlap smaller than 0,5 mm, step folds are sufficient to develop the necessary power to align the arch. In case of a greater dental crowding it is necessary to increase wire elasticity by shaping the vertical folds in a “U” mode. Thus, charge/deflection relation is decreased, resulting in a bigger and more long-lasting activation.

In order to prepare the dental surface to the adhesion, teeth are first cleaned. Then, surfaces to be bonded are etched for 30sec and an adhesive is applied and polymerized for 20sec.

In the following figures we analyze some activations for opening spaces in case of crowding.

Figure 1: the pre-shaped retainer with U folds between n.31 and n.41 and between n.42 and n.43 is bonded on n.31. A very charged fluid composite is used.

Figure 2: by closing the handle of about 2 mm between n. 31 and 41 the retainer is bonded on n. 42. In this phase it is important to keep the vertical plan of the wire, checking with another utility tool (tweezers) that the wire doesn't move up when the handle is closed. Attention must be paid, not to let fluid composite flow in the inter-dental space and at a gingival level in order to avoid periodontal problems. Obviously, the fluid composite must never be positioned at a handle level. To notice that retainer, after being bonded on n. 31 and 41, is more moved towards the lingual surface compared to n.41.

Figure 3: the retainer is pulled over through an utility tool at n. 41, moving it from a lingual to a vestibular way and it is bonded.

Figure 4: alignment is obtained when the handle creates a space through the expansion and n.41 is moved lingually.

In the following videos we analyze a shaping and handle bonding sequence example to obtain the expansion and alignment.

RETAINER SHAPING VIDEO

RETAINER ASSEMBLING VIDEO

References

1.Macchi A, Cirulli N. "Fixed Active Retainer for Minor Anterior Tooth Movement". Journal of Clinical Orthodontics, 2000.

2.Macchi A, Rania S, Cirulli . "Una proposta per la gestione di disallineamenti anteriori: il mantenitore attivo di contenzione (MAC)". Mondo Ortodontico, 1999.

For further information:

Dr. Fabio Cozzolino

fabio.cozzolino@fastwebnet.it

Dr. Anna Mariniello

anna.mariniello@libero.it

A NEW TECHNIQUE FOR RESTORING PROSTHETIC SPACE IN IMPLANT REGION: A CASE REPORT

Dr. Fabio Cozzolino

Dr. Anna Mariniello

 

In planning treatment of a prosthetic-implant patient, to obtain a propitious prognosis of a long term rehabilitation, a multi-discipline approach is elementary. However, in some cases, despite the commitment to realize an ideal treatment plan, it may happen to face up with an inadequate space when prosthetic procedures start.

Such a likelihood may be due to an occlusive stability lack, erroneously not corrected at the beginning of the treatment, or to the limited compliance of the patient who often does not respect periodical recalls established by the dentist. If there is not a correct occlusive mechanism or adequate space keepers, dental elements near the edentus saddle can carry versions of few mms which bring to significant prosthetic difficulties. In extreme cases, it may be impossible to associate implant-prosthetic components because of an inadequate occlusive space to access the implant neck.

For these cases, by taking advantage of the implant (bone-integrated, it is a steady anchor point and so it cannot move from its position), we created a technique to move dental elements. This idea was born by observing the spaces created mesially and distally to the molars using elastic divisors to insert bands in orthodontics. This technique permits to solve simply problems of space recovery in a non invasive way. It determines an orthodontic movement of uncontrolled inclination suitable for the resolution of these dental inclinations.

Case report

Patient S.R., a 32 year old male, was successfully treated by surgical implant therapy in the 16 area, in order to replace a dental element previously avulsed. A careful analysis of the spaces was carried out during treatment planning to introduce fixture in a prosthetic position optimally guided. Regardless, the patient missed periodical controls and returned 2 years after implant surgery. A mesial version of the element n. 17 was promptly highlighted (fig.1- 2) created during that time period.

This mesial version invalidated the restoring treatment plan, making necessary the distalization of the crown of the element n.17, in order to re-open correctly the prosthetic space. However, the patient refused both the realization of an inlay on the element n.17, necessary to recover at least a part of this space by changing the mesial profile of the tooth, and the traditional orthodontic therapy. Therefore, we proceed to screw a full implant abutment (fig 3) which was intra orally prepared to improve thicknesses in a mesial-distal and occlusive way, necessary to make a final prosthetic manufactured product (fig 4-5-6).

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Next, a traditional intra oral re-basement was made by using auto-polimerizing resin of a temporary crown made of an acrylic resin in the laboratory (fig. 7). The final definition of the latter was made by using a similar implant made in a laboratory (fig 8), so to improve the closing of the edge and reduce the patients’ discomfort (fig. 9-10-11-12-13).

The emerging morphology of the temporary element was realized so to permit an easy hygienic access to the implant neck. Finally, the temporary crown was cemented on the abutment with a temporary cement without eugenol (fig. 14). Once cement residuals were removed, an orthodontic elastic was inserted (fig. 15) in the contact area between the temporary crown and element n.17, acting by a slight force to distalize the crown of the molar, creating a movement of an uncontrolled inclination (fig.16).

After 10 days, a space of 1,5 mm was recovered (fig. 17-18-19) and we proceed to recreate a correct contact point by inserting a new elastic. After further 10 days we obtained an adequate prosthetic space and we proceeded with the prosthetic manufactured product.

 

This easy and versatile technique could be used in the edentular area where the space is limited for a crowning inclination of the near dental elements. Therefore, we could insert an implant in an edentule area with a more limited space compared to the one requested to make a prosthetic crown, foreseeing the future movement of the dental elements with this technique (fig. 20,21,22,23).

This technique may be suitable and efficacious in case the tooth to move undergo a mesial version or a distal version of the crown. In these cases, to recover the prosthetic space, an uncontrolled inclination movement is necessary and it can be easily obtained using a dividing elastic. Instead, when it is necessary to carry out a body movement it can be carried out by linking to the implants but other devices should be used.

 

For further information contact:

Dr. Fabio Cozzolino

fabio.cozzolino@fastwebnet.it