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60 Cards in this Set
- Front
- Back
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Teeth Rarely selected for exo
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Maxillary central
- Only if its deformed and can't be restored Mandibular central and lateral - Shows a tendency to develop deep overbites and disturbances of occlusion. - May extract when damanged, or entirely excluded or if theres extreme crowding of lower incisors Cuspids - Almost never exoed Mandibular cuspids - Never extracted if its possible to maintain them in a stable position First molars - May extract maxillary if mandibular 1st molar was previously lost and occlusion cannot be stabilized - Never indicated if theres agenesis of maxillary 3rd molars or if 3rd molars have poor size or shape Second molars - Maxillary 2nd can be extracted to allow entire dentition to move distally to achieve class 1 - Mandibular 2nd is not extracted for correction of malocclusions Third molars - May be extracted if removal allows better alignment of 2nd molars to be achieved |
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Teeth routinely extracted for ortho
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Maxillary lateral
- Because of frequent underdevelopment, misshape, or missing First bicuspids - Most likely extracted - Corrects class 2 div 1 problems, localized crowding in anterior or canine premolar area - Horizontal open bites Second bicuspids - Can be extracted due to being carious or blocked out of alignment - When minimal space is required and can be resolved by moving molars mesially |
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First stage treatment goals
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Bringing teeth into alignment
- Bring malposed teeth into arch - Control anteroposterior position of incisors, width of arches posteriorly, form of arch Correct vertical discrepancies by leveling out arches - Determine and control whether leveling occurs by elongation of posterior teeth or intrusion of incisors or a combination |
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Special problems of alignment during 1st phase
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1) Cross bite correction
2) Impacted or unerupted teeth 3) Diastema Closure |
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Cross bite correction during alignment
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- Important to Correct Posterior and Mild anterior crossbite in 1st stage. Severe anterior CBx is corrected in second stage
- Make distinctions between skeletal and dental problems and quantitate severity - Transverse Maxillary Expansion by opening Midpalatal suture. *Success is 100% before 15* - Correction of posterior crossbites via heavy labial expansion, expansion lingual arch, cross-elastics. Removable appliances are not compatible and is reserved for mixed dentition or adjunctive treatment. |
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Impacted or Unerupted teeth during 1st stage alignment
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- Most frequent impaction is Maxillary Canine
Problems - Surgical exposure: Important for tooth to erupt through attached gingiva and not alveolar mucosa. - Method of attachment: Least desireable is to place wire ligature around crown due to loss of periodontal attachment. Should simply expose an area on crown and directly bond an attachment. - Mechanical approaches for aligning unerupted teeth: Traction should begin as soon as possible after surgery. Ideally, fixed appliance should be in place before surgery. |
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Diastema closure during 1st stage alignment
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- Stable correction of diastema requires a surgery to remove interdental fibrous tissue
- It is an error to remove frenum and delay orthodontic treatment because scar tissue will form - Best to align teeth before frenectomy and remove interdental fibrous tissue |
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Leveling
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Depends on whether its absolute intrusion or relative intrusion will be satisfactory
- Relative intrusion is extrusion Leveling by Extrusion - Accomplished with continuous arch wires Leveling by Intrusion - Requires mechanical arrangement other than continuous arch wire attached to each tooth |
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Leveling by extrusion
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Leveling by Extrusion: Relative intrusion
- Accomplished with continuous arch wires and place an exaggerated curve of Spee in the maxillary and a reverse curve of spee in mandibular - May be necessary to replace initial resilient wire with a stiffer one to complete leveling Depends on whether its 18-slot or 22-slot 18-slot: Narrow brackets - After preliminary, second arch wire is 16mil stell with exaggerated curve of spee and reverse curve in lower arch - Alternative is 16 or 18mil M-NiTi with extremely exaggerated curve but patients cannot miss appointments 22-slot: Wider brackets - Initial alignment with 17.5mil twist or a 16mil A-NiTi, followed by 16mil Steel wire with reverse curve. Finish with 18mil round wire to complete - Rare that 20mil wire is needed |
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Leveling by Intrusion
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- Requires a mechanical arrangement other than continuous arch wire attached to each tooth
- Key is continuous intrusion using light continuous force towards apex - Avoid pitting intrusion of one tooth against another extrusion since extrusion will dominate Can be accomplished two ways - Continuous arch wires that bypass premolar and frequently canine - With segmented base arch wires and a auxiliary depressing arch |
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Leveling through Bypass Arches
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Most useful for patients who will have some growth
- Uprighting and distal tipping of molars pitted against intrusion of incisors - Classic version is Begg technique, but can use Edgewise to bypass premolars and canines and same idea in Rickett's utility arch - Forces must be small so select small diameter arch wire and use long span between first molar and incisors Problems - Only first molar is available for posterior anchorage so significant extrusion may occur - Should be avoided in patients with poor facial pattern - Intrusive force against incisors is applied anterior to center of resistance so incisors tend to tip forward |
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Leveling through Segmented Arch Wires
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- Depends on establishing stabilized posterior segments and controlling point of force against anterior segment
- Requires auxiliary rectangular tubes on first molars in addition to regular bracket or tube There may be forward movement of incisors as they are intruded - So can use bypass arches to tie the depressing arch back against the posterior segments - Preferably, can vary point of force application against incisors segment. |
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Differential Tooth Movement
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- Teeth are extracted in ortho to provide space to align crowded incisors without creating excessive protrusion
- Also to camouflage moderate Class 2 or Class 3 relationships when growth modification isn't possible Class 2 camo - Objective is to maintain existing class 2 relationship. Close 1st premolar space by retracting protruding incisor teeth. Must reinforce anchorage Extraction of Max and Mand premolars - Mandibular posteriors will be moved anteriorly and protruding maxillary teeth with be retracted. - Class 2 elastics will be used to assist in closing exo sites |
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Methods of extraction space closure
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Moderate anchorage situation
- This means that after alignment is completed, remainder or premolar extraction space should be closed with a 50:50 or 60:40 ratio 18-slot edgewise:Closing loops - Should be fabricated from rectangular wire to prevent wire rolling - Determined by three properties. 1) Spring properties: Amount of force it delivers and the way the teeth move. Determined by wire material, size and distance between attachment points 2) Moment generated: Root paralleling moments. To close an extraction space while producing bodily booth movement to bring apicies together 3) Location relative to adjacent brackets: Only the center of the V bend has equal forces and couples on adjacent teeth 22-slot edgewise - First retract canines by sliding, then retract 4 incisors with a closing loop - Moments necessary for root paralelling are automatically generated by the twin brackets normally used in 22-slop appliance - Rigid attachment of canine to the continuous ideal arch wire means the tooth won't move too far out if patient does not return to appointments |
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Maximum retraction and Maximum anchorage
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- Not always desirable to retract anterior teeth as far as possible after premolar extraction
- But to get maximum retraction, must reinforce posterior anchorage and reduce strain on posterior anchorage. Same for both 18 and 22 slot appliance - Avoid friction from sliding using closing loops - Add stabilizing lingual arches and proceed with closure. This will increase posterior anchorage 2:1 - Reinforce maxillary posterior anchorage with extra-oral force, and use class 3 elastics if needed 3:1 or 4:1 - Retract canines independently preferably using segmental closing loop and then retract incisors with a second closing loop. 3:1 |
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Root paralleling and Torque
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Root paralelling - Accomplished by placing an uprighting spring in vertical slot and hooking it beneath arch wire
Torque - Lingual root torque may be required of incisors were tipped lingually - Accomplished through auxilary appliance that fits through base archwire. Piggyback arch torque auxillary contacts near gingival margin and creates a moment arm of 4-5mm. - Begg technique, incisors are deliverately tipped and root torque is routine |
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Methods to correct vertical relationships
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Excessive overbite
- Assess why problem exists and observe vertical relationship between maxillary lip and incisor - An excessive curve of spee on lower arch can be cause of overbite, but can be elongation of maxillary incisors - So preferred solution is auxillary intrusion arch. Anterior open bite - Rarely caused by lack of upper incisor eruption so elongation is undesirable. - If due to excessive posterior eruption, can use high pull headgear to upper molars if thats the problem - If no problems with pattern of facial growth. Can elongate lower teeth to create a slight curve of spee. |
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Tooth size discrepancy
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- Should be accounted for initially, but often times, its dealt with during finishing stage of treatment
- Can reduce interproximal enamel. Stripping. - Most enamel reduction should be done initially. - Topical flouride treatment is always recommended immediately after stripping is done - If deficient, may have to leave space that could be closed with restorations. Usually occurs with small maxillary laterals. |
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Procedures to avoid relapse
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Causes
- Continued growth by patient in an unfavorable pattern - Tissue rebound after release of ortho force Controlling unfavorable force - Requires continuation of active treatment after fixed appliances have been removed - Can use extra-oral force with orthodontic retainers - Functional appliance rather than conventional retainer Control of soft tissue rebound - Hold teeth till soft tissue remodeling can take place - Some rebound still occurs - Can use overtreatment or adjunctive periodontal therapy. |
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Records required for an ideal orthodontic evaluation
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- Pre-tx, Post-tx, and post-retention records
- Includes Lateral cephalometric head plates, Models, PA's |
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Six most common limitations to successful orthodontic treatment
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- Psycho-Social Limitations (Uncooperative patient)
- Technical Limitations(Appliance limited therapy) - Environmental limitations(Habits or muscle imbalances) - Skeletal limitations (Unfavorable skeletal pattern) - Idiopathic Limitations(Root resorption, ankylosis, tooth size) - Improper diagnosis |
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Three parts of evaluating the orthodontic result
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History - Medical, Dental, Orthodontic
Radiographs - FMS should show even distribution of roots in bone with adequate interdental areas Clinical evaluation - Subjective nature of esthetic and functional standards |
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Compromises that will result from a tooth size discrepancy
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- Tooth size in both anterior or posterior teeth will affect functional occlusal tooth relationships
- Discrepancies may be evidenced in anterior-posterior relationships, overjet-overbite, or rotations |
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Fixed and removable retainers
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Removable
Hawley retainers - Most common - Incorporates clasps on molars and characteristic outer bow with adjustment loops from canine to canine - Covers palate and provides potential bite plane to control overbite - Can also provide some tooth movement Removable Wraparound retainers - Clip-on retainer - Plastic bar, usually wire reinforced, along labial and lingual surfaces of teeth Fixed - Used in situations where intra-arch instability is anticipated and prolonged retention is planned - Maintenance of lower incisor position during late growth - Diastema maintenance - Pontic or implant space maintenance - Keeping extraction spaces closed in adults |
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Active retainer
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- Relapse or growth change after orthodontic treatment will require tooth movement during retention
- Reserved for two specific situations. Realignment of irregular incisors and functional appliances to manage class 2 or 3 relapse. - Accomplished with a removable appliance that continues as a retainer after its repositioned teeth |
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Indications and Contra-indications for rapid palatal expansion
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Indications
- Bilateral maxillary construction. Can manifest as bilateral crossbite with little to no mandibular deviation or unilateral crossbite with definite lateral mandibular deviation. - Class 3 cases, especially non surgical ones - Inadequate nasal capacity exhibiting chronic nasal respiratory problems - Mature cleft palate cases - Selected arch length problems with no crossbites Contraindications - True unilateral crossbite. Since bilateral expansion of true unilateral crossbite will create a mandibular displacement laterally to the normal side since normal side is over-expanded - Age - Gingivitis must be treated first before placement - Patient should be free of pathology - Dilantin therapy patients must be observed closely |
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Difference between real and relative maxillary deficiency
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Real - Compression of maxilla with constriction of buccal tooth segments. See high narrow palatal vault
Relative - When maxilla is of expected size but mandible is too large. If there is a buccal segment crossbite due to this problem, still treat maxilla because compression of mandible is not advisable. |
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Records and Documentation for palatal expansion
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Records
- Orthodontic study casts - Posteroanterior radiograph - Lateral radiograph - Occlusal radiograph - Intra-oral photo - Extraoral photos Documentation - Initial records - After suture opening - At time of fixed appliance removal |
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Two types of appliances used in rapid expansion
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1) Tissue borne fixed split acrylic appliance
2) Fixed all wire framework appliance |
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Various parts of palatal expansion appliance
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- Framework is baseplate made from acrylic or similar material and serves as a base in which screws or springs are embedded and clasps are attached
- Active element is always jackscrew placed to hold the parts together |
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Activation and stabilization of expander
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- Most screws open 1mm per complete revolution so one quarter turn is 0.25mm
- Rate should not exceed 1mm per month - Activator screw should not be activated more than twice a week |
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Changes that occur in nasal cavity from expansion
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- Many patients claim an increased capability for respiration following palatal expansion
- However, theres variation in the amount of gain in air volume |
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Skeletal and Dental changes that occur with expansion and effects on Mal-occlusion
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Changes
- Opening of Mid-palatal suture is parallel while triangular inferosuperiorly with apex being nasal cavity. - Maxillary central incisors always separate but then move mesially and return to original axial inclinations - Alveolar process bend and move laterally with maxillae - Downward displacement of maxilla is routine but forward displacement varies with case - Mandibular rotation in a downward and backward direction with subsequent recovery is noted Effects - Class 3 Deep bite: Usually improved due to downward and forward movement of maxilla with downward backward movement of mandible - Class 3 Open bite: Both favorable and unfavorable. Maxillomandibular dysplasia becomes less but open bite gets worse - Class 2 dev 1: Gets decidedly worse - All open bite cases are adversely affected |
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Difference between orthodontic and orthopedic force and effects on treatment
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- Orthopedic force rather than orthodontic force is necessary for palatal expansion
- Designed to produce minimal tooth movement and maximal bone movement - 3-13pounds of average force buildup - Residual force tends to accumulate as widening continues and builds up faster in older patients due to articular sites in older patients offering more resistance |
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Types of retention utilized after completion of rapid expansion
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- After 3 month stabilization with fixed appliance, Hawley is placed
- Retainer is worn for 6mos to a year unless full orthodontic appliance is placed |
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Approaches in treating mandibular deficiencies and maxillary excess
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- Functional appliances enhance mandibular growth while headgear retards maxillary growth
- So use functional appliance to treat mandibular deficiency and headgear for maxillary excess - Acceleration of mandibular growth often occurs but long term increase in size is difficult to demonstrate - Effect on maxilla is almost always observed along with mandibular effects |
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Working bite
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- Desired mandibular position
- Obtained with multiple layers of wax that is maintained - Working bite for class 2 patient is obtained by advancing mandible forward to move condyles out of fossa |
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Effects upon maxilla and mandible with functional appliances and headgears
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- Class 2 correction is obtained as mandible grows forward normally while similar forward growth of maxilla is restrained so mandibular growth is necessary part of treatment response.
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How to construct a facebow
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- Inner bow should be expanded 2mm symmetrically so when placed in one tube, it rests just outside other tube
- Outer bow should rest several mm from cheeks - Must be cut to proper length and have hook formed at end - Length and vertical position of outer bow are selected to achieve correct force direction relative to center of resistance |
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Treating maxillary deficiency
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Transverse Maxillary constriction
- Skeletal distinguished by narrow palatal vault, produces posterior crossbite and is an indication for treatment at the time its discovered - Can be corrected by opening up mid-palatal suture before growth spurt - Can be done via Splint removable plate with jackscrew or heavy midline spring, Quad helix Lingual arch, or Fixed palatal expander with jackscrew Anteroposterior and Vertical maxillary deficiency - Both can contribute to class 3 - Prefer to move maxilla more anterior and inferior and increase size - Facemask treatment obtains anchorage from forehead and chin - Functional appliance made with mandible positioned posteriorly and rotated open and with pads to stretch upper lip forward |
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Theory behind chin cup
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Theoretically, Extra-oral force directed against mandibular condyle will restrain growth but has not worked in humans
- However, it does change direction and rotates chin down and back - Lingual tipping of lower incisors occurs from the pressure - |
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How to intercede with facial asymmetry
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- Can be congenital or result of trauma to condyle causing a restriction in growth after injury, not displacement itself
- When condylar fracture is diagnosed, maintaining function is key to normal growth - Short fixation times with rapid return to function. Use functional appliances to minimize growth restriction such as activator or bionator type that symmetrically advances mandible to edge-to-edge incisor position. Forces patient to translate mandible so remodeling can occur with mandible in unloaded forward position - Most condylar fractures are not diagnosed at time of injury so asymmetric mandible in child is most likely due to trauma - Extent to which affected side can translate will determine prognosis - Surgical intervention in an asymmetric situation prior to adolescence is only done to create an environment in which growth is possible - Surgery is only indicated when abnormal growth is making a problem worse as in ankylosis or one side. |
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Definition of cerebral palsy
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A group of chronic non-progressive disorders of motor centers or pathways of the brain
- Characterized by paralysis, weakness, contractures, spasticity, incoordination, and tremors - Descriptive term. So this illness can occur at any stage of human development - These children may have other brain problems such as retardation, seizures, sensory deficits, learning and speech disorders, emotional and behavioral problems |
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Incidence of cerebral palsy in children
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- One of the most common causes of crippling in children
- 1.5-3 cases per 1000 individuals of all ages - 100-600 new cases per 100,000 children - 4-6 per 1000 live births or 1/200 live births and 1-2 new cases per 1000 children aged 5-12 - 1/3 die by age 6, other 1/3 are institutionalized |
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Etiological factors of cerebral palsy
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Prenatal
- Congenital defects - Severe Jaundice - Anoxia, Prematurity, Placental defects - Trauma - Malnutrition, Metabolic - Maternal Rubella - Hereditary Perinatal - Highest incidence - Trauma during delivery - Anoxia due to anesthetics, narcotic overdose, mechanical respiratory obstruction - Difficult labor Postnatal - Trauma - Encephalitis viral or bacterial - Convulsions - Neoplasms - Vascular conditions secondary to trauma or infection - Intoxications from lead, arsenic etc |
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Major types of cerebral palsy and describe each
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Spastic
- Most common. 50% - Pathologic stretch reflex with increased activity of deep tendon reflexes - Frequently associated with prematurity and anoxia at birth damaging cortical centers - Children tend to be introverted and apprehensive. Can have minimal to severe retardation Athetoid/Dyskinetic - 25% - Involuntary unccordinated movements accentuated when voluntary movements are attempted - Associated with lesions of basal ganglia and extrapyramidal tracts - Children do not have mental deficits like in spastic but can have emotional and behavioral problems - Speech problems Ataxic - 15% - Lack muscular coordination due to disturbaces in balance centers due to cerebellar lesions - Constant eye movements, nausea and vertigo, - Sitting erect is impossible without support - Children have less retardation Rigidity - 10% - Muscular resistance due to imbalance in agonist-antagonist - Hypertonic muscles in affected limb - Retardation is more common Tremor - 5-10% - Usually a latent symptom observed in older children and adults - May resemble motor disorders in Athetoid but with no mental retardation |
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Paraplegia
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- Sensory and motor deficits of legs, lower trunk and pelvis
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Diplegia
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Paralysis affecting like parts on both sides of body
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Hemiplegia
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Paralysis on one side
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Quadraplegia
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Paralysis of all four limbs
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Secondary medical problems of cerebral palsy
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Seizures
Diabetes Mental retardation Impaired hearing or vision Speech disorders |
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Environmental and Social problems of cerebral palsied child
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- In many instances, emotional, social, psychological, and environmental factors presents greater obstacles for mildly affected child than medical handicap alone
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Dental problems of Cerebral palsied child
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Enamel hypoplasia - Caused during tooth development
Dental caries - Varied opinions and may be due to food, OH, neglect Gingivitis and perio disease - higher frequency due to diet, OH and malocclusion Malocclusion - Higher frequency of anterior open bite, anterior dental prognathism, Crowding, upper arch constriction. |
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Major dental anomaly seen in cerebral palsied children
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Enamel hypoplasia seen 20-100%
- Athetoid group has highest incidence - CP from Rh incompatibility have highest incidence of this defect |
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Indications and How to control physical movements of cerebral palsy child
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Indications
- Cannot be prevented with medication but drugs may be directed towards apprehension - Degree and extent of total disability will determine proper techniques Spastic or Rigid - May require little support or restraint Atetoid - Restraints for affected limbs and body Ataxic - Stabilization of head and mouth - Armamentarium for stabilization and support include properly contoured dental chairs, pillows, body wraps or sheets, arm warps, and contoured head rests - Severely affected children may require general anesthesia |
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Psychological management of cerebral palsied child
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- CP child with minimal intellectual and emotional deficits can be managed like normal child
- Patience, understanding, and routine techniques of behavioral modification may be used to allay fear and apprehension without use of premedications Recommendations - Quiet operatory devoid of distractions - Voice control - Praise for acceptable behavior - Shaping and conditioning behavior - General anesthesia is indicated for CP child who cannot respond favorable to other techniques of behavioral management with extensive oral problems |
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Rationale for total treatment of cerebral palsied child
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- Should parallel philosophies and goals of treating normal child
- Plan dental rehabilitation around total medical and environmental status Treatment as follows - Management of physical movements - Psychological or behavioral management - Definitive dental care - Preventative procedures such as flouride, OHI, Diet counseling, recall visits, sealants |
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Three most common primitive reflexes that persist in young CP patient
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Asymmetric tonic neck reflex
- If patients head is suddenly turned to one side, arm and leg on the side turned towards will extend and stiffen - Opposite side will flex Tonic Labyrinthine Reflex - If head suddenly falls backward while supine, back may assume position known as postural extension. Legs and arms straighten out and neck and back arch Startle reflex - Sudden involuntary and forceful bodily movements - Produced when patient is surprised |
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Intra-oral conditions more common or severe in cerebral palsy patients and their etiological factors
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- Periodontal disease: Greater frequency caused by poor OH, high carbs, Phenytoin induced hyperplasia
- Dental caries: Incidence does not seem greater than in gen pop Malocclusions - 2x than normal. Protrusion of maxillary anteriors, excessive overbite/jet, open bites, and unilateral crossbites Bruxism - Seen in Athetoid: May see TMJ disorders Trauma - More succeptible to trauma. Related to increased tendency to fall. |
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12 Suggestions for clinician treating CP patients
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1) Consider treating in the wheelchair. Can be tipped back into dentist's lap
2) Ask about mode of transfer to chair. Two person lifts recommended if theres no preference 3) Stabilize head throughout treatment 4) Place and maintain patient in midline of chair with arms and legs close to body 5) Keep patients back slightly elevated to minimize difficulties swallowing. Avoid being completely supine 6) When placing patient in chair, determine degree of comfort and assess position of extremities. DOn't force limbs into unnatural positions 7) Use immobilization judiciously 8) To control jaw movements, choose from mouth props and finger splints 9) Minimize startle reflex with abrupt movements, noises, lights without warning 10) Introduce intraoral stimuli slowly to avoid eliciting gag reflex 11) Consider use rubber dam 12) Work efficiently and minimize patient time in chair to decrease muscle fatigue |
