WO2011159261A2

WO2011159261A2 - Intermaxillary lip bumper

Info

Publication number: WO2011159261A2
Application number: PCT/SY2010/000008
Authority: WO
Inventors: Mohamed Youssef; Abdulsalam Al Domaini
Original assignee: Mohamed Youssef; Abdulsalam Al Domaini
Priority date: 2010-06-13
Filing date: 2010-07-06
Publication date: 2011-12-22
Also published as: WO2011159261A3

Abstract

An appliance for combined functional and active orthodontic treatment of skeletal class II malocclusion is designed. It consists of affixed orthodontic upper molar bands and two 1 mm diameter stainless steel wires inserted into headgear tubes. Each of them is attached anteriorly to Hp bumper separately. The two lip bumpers are positioned into the lower labial vestibule.

Description

Professor Dr . Mohamed Youssef Dr .Abdulsalam Al Domaini

Intermaxillary lip bumper

The previous technical art: (Background)

The achievement of esthetic and Functional optimum of dentofacial complex requires correcting discrepancies of jaws relationship. One of these discrepancies is the Angles Class Π Division I- malocclusion (Antanas ,Vilma Mantas; 2006) * that affects about third of the general population (Cozza et al,2006). Many treatment methods have been suggested and applied to correct Class II malocclusion, such as Headgear to restrain the maxillary growth, where it was thought that maxillary over-development is the main factor in Class II development.

However, many studies and cephalometric analyses have recently revealed that most of CI II cases are due to mandible retro-position. Thus, many Functional orthodontic appliances have been invented to stimulate mandibular jaw advancement. This change in the opinions about the etiology of Class II- malocclusion is also emphasized by Moss and Franker s studies, which stressd the role of functional factors in Class Π development.

Orthodontic functional therapy is based on utilizing the function of oral structures in modifying the remaining facial growth and thus changing skeletal relationship through affecting bone remodeling. Now, it is evident that muscular pressure is the primary factor in redirecting ftmctionai forces during the treatment of malocclusion.

Invented by Robin in 1907, Monobloc was the first orthodontic functional appliances applied in Europe and used as an emergency tool to hold the mandible in the anterior position, thus releasing airway in children who were complaining from congenital mandible retrognathism and macroglossia. However, the Andreson^'s activator was the first functional appliance used to correct skeletal class II malocclusion. It helps to hold the mandible in anterior position, thus evoking mandibular growth and consequently correcting distal jaws relationship (Proffit et al, 2000). On the other hand, the bulkiness of the activator and its wearing at night only disadvantaged its indications by many professionals, so other appliances for class II correction were suggested to overcome these problems, such as SOA-and EOA after Klammt,the Bionators after Blaters and the Twin-block after Clark, ect. On the other hand, Rolf Frankle utilized osteoperiosteal traction in functional therapy through directing and correcting the muscular activity. Frankle proposed the possibility of osteoperiosteal formation through muscular traction of periosteum. In mandibular retrognathism with horizontal growth pattern, Frankle embodied labial bumpers in his appliance in order to avoid the labial pressure on dental arch and enforcing periosteal traction through over activity (tension) of mental and labial muscles. This muscular over- tension on periosteum was proposed to stimulate bone deposition on anterior edge of the mandibular alveolar crest. Obviously, the tongue musculature would be free to act on anterior mandibular segment to achieve equilibrium around the dento-alveolar compound.

Obviously, the overall effect of bumpers in FR-II is to limit the negative labial muscular pressure on dental arch and consequently permit the normal & sagittal growth of the dental and skeletal complex of the mandibule, hence achieving the tongue muscular segment equilibrium (Frankle, 1984) .

Lip bumpers have been used along with fixed orthodontic appliances for years to control anchorage, to maintain space, to improve labial muscles activity, to increase dental circumference and release crowding, and for treat of lower lip sucking or biting habit(Attazodeh F,Adenwalla ST, 1988; &Bergersen EO,1972)

The mechanism of action in lip bumpers is to break the muscles equilibrium between labial and tongue muscles in favor of the latter; the net effect is lateral and anterior expansion of dental arch with a subsequent dental movement in the same direction.

Some modifications on lip bumpers were introduced by Hallaj and Youssef (2006) where labial bumpers were put into the buccal vestibule in one hand and could be applied in combination with fixed orthodontic appliance through molar band tubes of the mandible on the other hand. These modifications revealed obvious dental and skeletal changes.

Based on the above-mentioned background, we present a new appliance utilizing muscular traction of subperiosteum in performing functional therapy. This is achieved through enforcing anterior positioning of the mandible in class II malocclusion cases, hence stimulating its growth and consequently correcting distal jaw relationship. This mechanism is independent of mandibular dento- alveolar anchorage and it will reduce the duration of malocclusion therapy as it could be applied along with the fixed appliances during the orthodontic treatment.

Detailed description of the invention:

- Functional bite taking (where the mandibular jaw is positioned more anterior than usual).

- Separator elastic putting in mesial and distal of the upper first molars.

- Separator elastic removing and upper bonds trying then removing them.

- Elastic separators reputting.

- Upper 1st molars banding on study cast

- Drawing wire and labial bumpers on study cast then wire is bended to take the shape of the drawing (the diameter of the wire is 1mm and made of stainless steel )

- Relieving of the labial bumpers by wax

- Acrylic shaping of labial bumpers and then curing

- Appliance removal, finishing, polishing and disinfection.

- Elastic separators removed and upper molars banding.

- Inserting the appliance into headgear tubes of the upper molars bands.

- Patient instructions.

- The appliance is mainly used for correction of the retrognathic mandible in skeletal class II malocclusions.

- The appliance utilizes the subperiosteal muscular attraction to affect mandibular length and correcting the mild anterior crowding in the mandible through retracting the pressure applied on these teeth by the lower lip along with achieving bodily movement of the lower anterior teeth through subperiosteal traction applied by lip bumpers.

- The width of the mandible can be increased by subperiosteal bone apposition through retracting the pressure applied by the buccinators muscles through the wire that passes buccaily along the lower teeth.

- The lower facial vertical height can be increased (in class Π cases associated with horizontal growth pattern) by permitting spontaneous eruption of the posterior teeth into the space created during the advancement of the mandible.

- The mandible can be incrementally displaced through activation of the vertical loop.

- The appliance can be used to treat some cases of class III malocclusion (where the upper jaw is retracted) through inverting its use as the appliance is inserted into orthodontic bands attached to lower permanent 1^st molars while the lip bumpers positioned in the upper labial vestibule .

- The mesially drafted and rotated upper molars can be distalized and rerotated respectively along with the potential of expansion of the upper arch through the reflex action of the lower lip in response to the action of the lip bumper.

Claims

Claims to be protected:

1- An appliance for correcting the retrognathic mandible in skeletal class II malocclusion where it consists of:

a. Orthodontic bands cemented into maxillary permanent 1^st molars. b. Orthodontic wire, 1 mm in diameter made of stainless steel in each side where it has vertical and horizontal loops and diagonal slope toward the buccal vestibule, in addition to acrylic bumper c. The two wires are connected to each other by a connecting wire positioned over labial fernium.

2- The appliance in claim 1; where the subperiosteal muscular attraction is utilized to affect mandibular growth and to treat skeletal class II malocclusion, consequently correcting distal jaw relation by anterior positioning of the mandible.

3- The appliance in claim 1 ; where the length of the mandible can be increased by subperiosteal bone apposition in the mental process, consequently correcting the mild anterior crowding of the mandible through retracting the pressure applied on these teeth by the tongue along with achieving bodily movement of the lower anterior teeth through subperiosteal traction applied by lip bumpers.

4- The appliance in claim 1 ; where the width of the mandible can be increased by subperiosteal bone apposition through retracting the pressure applied by the buccinators muscles through the horizontal wire that passes bucally along the lower teeth.

5- The appliance in claim 1; where the lower facial vertical height can be increased (in class II cases associated with horizontal growth pattern) by permitting spontaneous eruption of the posterior teeth into the space created during the advancement of the mandible.

6- The appliance in claim 1 ; where the vertical loop can displace the mandible anterior incrementally. 7- The appliance in claim 1; where the vertical changes can Be achieved through activation of horizontal loop.

8- The appliance in claim 1; where the appliance can be used to treat some cases of class ΠΙ malocclusion (where the upper jaw is retracted) through inverting its use as the appliance is inserted into orthodontic bands attached to lower permanent 1^st molars while the lip bumpers positioned in the upper buccal vestibule .

9- The appliance in claim 1; where the mesially drafted and rotated upper molars can be distalized and rerotated respectively along with the potential of expansion of the upper arch through the reflex action of the lower lip in response to the action of the lip bumper.

10- The appliance in claim 1; where the TP A (Trans-Palatal Arch) can be added in cases where distalization of the upper molars is contraindicated.