Monobloc Flashcards
(23 cards)
Monobloc
Tooth borne active appliance- part of functional appliances
First introduced by andresen but without retention elements and was held in mouth by patient
New monobloc
Haupl-Andresen modification
Monobloc consists of
- Bimaxillary acrylic base
- Labial bow
- Retention clasps
- Fixed in construction bite
- 0.8-0.9mm round stainless steel wire
- 0.7 mm diameter round stainless steel wire
Additions that can be made to monobloc
Active springs or expansion screw
- 0.5mm diameter
- In this case monobloc called orthodontic appliance with combined action
Monobloc indications
- Maxillary prognatism
- Mandibular prognatism
- Symmetrical bimaxillary compression
- Laterodeviation of mandible
Monobloc labial bow location in class II
Buccal surfaces of maxillary anterior teeth
Monobloc labial bow location in class III
Buccal surfaces of mandibular teeth
Monobloc fabrication requires
- Quality plaster models
- Working bite registration
Planes of monobloc fabrication
- Sagittal plane
- Vertical plane
- Horizontal plane
Monobloc fabrication in sagittal plane
- Class I molar relationships- distal to mesial occlusion to wax bite
- Class II- Patient protrude mandible forward
- Class III- Patient retracts mandible as far back as possible until edge to edge bite in anterior segment
Monobloc fabrication in vertical plane
1-3 mm open bite between incisal edges of maxillary and mandibular teeth
Monobloc fabrication in Horizontal plane
Maxillary and mandibular midlines aligned
Acrylic base borders in maxilla
- Extends to Incisal edges of incisors and canines buccally
- Midline of occlusal surface of premolars and molars
- Distally reaches distal surface of molars- arch form contour in palate area
Acrylic base borders in mandibe
- Lingual surfaces of mandibular anterior and posterior teeth
- 5-6 mm below tooth cervices
May be inserted for mechanical force application in the palate acrylic base
Expansion screw
Parallel to long axis of posterior teeth
Therapeutic aim of monobloc
- Mandibular protraction of class I molar occlusion
The anterior interocclusal acrylic intrudes the
Mandibular front teeth
The posterior interocclusal acrylic disscludes
- The bite
- Facilitates correction of vertical descrepancies(deep overbite)
In the maxilla the acrylic is grinded
For posterior teeth eruption guidance and bite opening
Distally
In the mandible the acrylic is grinded
For posterior teeth eruption guidance and bite opening
Mesially
If expansion screw is present
- Interocclusal acrylic transfers active force to posterior teeth
- Moves them buccally
Force application of maxillary anterior teeth achieved with
- Labial bow
- Active springs
Monobloc appliance wear time
- Night time
- 2-3 hours during day
