28. Appliances in aid of orthodontic prophylaxis Flashcards
(30 cards)
Interceptive appliances and their primary function
- Eliminate abnormal oral habits that lead to development of malocclusion=>
- Alter imbalance in surrounding musculature=>affect normal growth and development of dentition=>
- In primary and mixed dentition stages
- Primary and secondary prophylactic purposes
How interceptive appliances classified
- Passive Interceptive Appliances
- Active Interceptive Appliances
- Space Maintainers
Operational principle of passive interceptive appliances
- Setting physical barrier=>
- Prevent recurrence of oral habit w/out creating new conditioned reflex=>
- Interrupts the reflex arc mediation
oral habit=> acquired and sustained conditioned reflex
Oral screen and when is it used
- Eliminate oral habit of mouth-breathing=>
- When nasal breathing is not obstructed=>
- Located in vestibule between alveolar ridges and the perioral muscles
-Oral screen=>according to Kraus
-Factors that can obstruct nasal breathing=>tonsillar hypertrophy, adenoid hyperplasia, chronic tonsillitis, allergies, infections, or septal deviation
Oral screen fabrication and usage
- Usage=>gradually eliminates mouth-breathing=>
- Three 5-6mm diameter apertures grinded in anterior portion of screen and progressively closed w/ acrylic at 3-4 week intervals
- Wire ring can be inserted in anterior portion=>
- Increase muscle tonus of a hypotonic orbicularis oris=>
- Included in myofunctional exercises
- Fabrication Technique=>
- Construction bite registration taken in physiological rest position=>
- Wax relief placed 4-5mm buccally of gingival margins to separate teeth from appliance=>
- Extends to vestibular sulcus vertically and terminal teeth distally
-Physiological rest position=>for stable positioning since the appliance is worn only at night.
-Fabricated from self-curing acrylic resin
indications of Lingual plate with tongue barrier
- Tongue thrusting
- Infantile swallowing
- Digit sucking
Lingual plate with a tongue barrier design
- Acrylic resin extending to cervices of mandibular anterior teeth vertically and to terminal teeth distally=>
- Retention clasps and a labial bow=>
- Barrier may be acrylic extension or 0.9mm diameter stainless steel wire grill
- Fabrication=>Made in centric occlusion of plaster models=>
- To prevent trauma to lingual frenulum during swallowing, w/ added acrylic resin in interdental embrasures=> support
indications of Mandibular plate with tongue barrier
- Infantile swallowing and tongue thrusting=>
- Anterior proclination and potential anterior crossbite
Mandibular plate with a tongue barrier design
- Acrylic base w/ tongue barrier extension, retention clasps, and labial bow
- Fabrication=>made on a plaster model in centric occlusion
- If anterior bite=>acrylic bite plane added=>
- Wax relief from mandibular anterior teeth facilitates retroclination through activation of labial bow=>
- Prevent secondary anterior crossbite
Oral screen plate type I and its indications
- Mouth-breathing and digit sucking
- Design=>Kraus’ oral screen in lingual plate w/ elastic wires and retention clasps
Oral screen plate type II and its indications
- Lower lip sucking
- Design=>mandibular acrylic plate w/ oral screen=>
- Circumferential clasps w/ acrylic pads on distal surfaces of terminal teeth=>
- Increase retention
Operational principle of active interceptive appliances
- Create dominant unconditioned reflex=>
- Suppresses conditioned reflex of oral habit
- Induces involuntary response=>
- Overpowers habitual conditioned response
How active interceptive appliances work to eliminate oral habits
- Provide stimulus triggering unconditioned reflex=>
- Pricking finger or lip=>
- Suppresses conditioned reflex of oral habit=>digit sucking or lower lip sucking
Design of appliance for dominant-reflex elimination of digit sucking
- Mandibular acrylic plate located buccally w/=>
- Anterior horizontal acrylic plate and circumferential clasps w/ acrylic pads on distal surfaces of terminal teeth=>
- Increase retention
- Anterior horizontal plate=>spring mechanism w/ 3-4 sharp spikes attached to main acrylic base w/ coil springs=>
- Separated from mandibular anterior teeth
Appliance for dominant-reflex elimination of digit sucking mechanism of action
- Thumb placed in mouth=>
- Presses horizontal plate of appliance=>
- Spikes to eject and prick thumb=>
- Pain causes instinctive removal from mouth
- Unconditioned reflex (pain response) dominates acquired conditioned reflex of thumb sucking
Design of appliance for dominant-reflex elimination of lower lip sucking
- Mandibular acrylic plate=>
- Located buccally
- Anterior horizontal acrylic plate
- Circumferential clasps w/ acrylic pads=>
- On distal surfaces of terminal teeth for increased retention
- Anterior horizontal plate has vertical spikes=>
- In passive position on plate and directed toward oral surface of lower lip=>
- Prick it during lip sucking
-It can also be fabricated with molar bands as a fixed appliance
Purpose of space maintainers
- Premature loss of primary teeth=>
- Maintain space needed for unerupted permanents
- Used in premature loss of permanent teeth when prosthetic treatment cannot be initiated=>
- Unfinished facial skeleton growth (typically under the age of 17 or 18).
How space maintainers classified
Fixed or removable
Indications for using space maintainers according to Atanasov
- Height of alveolar crest covering unerupted permanent tooth > 1mm
- Root length of permanent tooth smaller than crown height
- Mesiodistal width of space required for permanent tooth eruption decreased in comparison to opposite quadrant
-Measurements made on a periapical radiograph
Requirements for space maintainers
- Maintain entire mesiodistal space created by loss of teeth
- Restore function
- Prevent over-eruption of opposing tooth
- Simple construction
- Not exert excessive stress on opposing teeth
- Permit maintenance of oral hygiene
- Not restrict normal growth and natural adjustments during transition from deciduous to permanent dentition
Design of fixed space maintainer for a single primary tooth loss
- Wire fixed to molar bands=>
- 0.9mm diameter round stainless steel wire soldered to pre-fabricated molar band=>
- Band w/compensatory loops in bucco-lingual direction=>
- Mesially=>bent according to curvature of distal surface of adjacent tooth
Design and replacement protocol for a removable space maintainer used for premature loss of two or more posterior teeth
- Partial denture design=>
- Acrylic base extends to middle of alveolar crest w/out reaching buccally
- Retention clasps engage interdental embrasure undercuts
- Artificial teeth added to defect area of acrylic base
- Replaced periodically according to the age of patient=>in primary dentition, not replaced until 4-4.5 years of age, and after the age of 6
- Replaced every 12 months or less, depending on tooth eruption pattern
-circumferential clasps can be used instead of retention clasps
-Artificial teeth facilitate masticatory efficiency
Indicated for premature loss of two or more primary anterior teeth
- Removable Kemeny-type partial denture w/ acrylic clasps (Gesheva-Likov modification)
- Similar to partial denture for posterior segment=>
- Space maintainers in anterior segment replaced every 6-8 months
System of standard, pre-fabricated interceptive appliances
Trainer system
