Ortho 2 midterm Flashcards
1
Q
Why do you retain?
A
Periodontal tissue changes, still growing.
The original malocclusion would be the stable position and the ortho result may be unstable.
2
Q
What are the causes for return of malocclusion?
A
Gingival and PDL, cheek, lip and tongue pressure, irregularity of teeth, differential jaw growth, changes in occlusal relationships.
3
Q
During ortho, what are the changes to periodontal tissues?
A
Widening of PDL and mobility. Sisruption of collagen fiber bundles.
4
Q
How does the restoration of normal PDL occur?
A
Only after appliaces are removed. Theeth bust be able to respond to mastication with slight movement. The reorganization takes place over 3-4 months to return to active stabilization
5
Q
Active stabilization
A
considered “normal”
PDL equilibrium helps maintain tooth position. It is the same as the eruption mechanism.
Disrupted by ortho treatment
6
Q
What resists active stabilization?
A
Imbalances in tongue/lip/cheek pressure. Pressure of gingival fibers.
7
Q
What are the principles of retention?
A
Full time retention for the first 3-6 months, so it promotes PDL reorganization. Retain for a minimum of 12 months. If there is instability or growth, you need long term retention.
8
Q
What are growth related problems?
A
Growth pattern stays the same as pretreatment and problems arise.
9
Q
Transverse Growth
A
Ends early and is relatively stable.
10
Q
AP growth
A
Ends at adulthood.
11
Q
Vertical growth
A
Last to stop
12
Q
How doe relapses of class II corrections occur due to tooth movement?
A
Forward in upper arch and backwards in lower arch.
13
Q
How do relapses of class II corrections occur to differential jaw growth?
A
Inadequate MN growth. Restrained MX growth leads to post treatment rebound and more MX than MN growth. You can fix it with night time appliance and regular retainers. The younger the pt. the longer the retention.
14
Q
How do you maintain a class III retention?
A
Chin cup/functional appliance. Surgery after growth.
15
Q
How do you maintain deep bite retention?
A
MX Hawley with anterior bite plane. Long term wear is necessary.
16
Q
How do you prevent the effects of growth and maintain open bite retention?
A
Stop finger/thumb habits.
High pull/HG open bite appliance. Retention until growth is completed.
17
Q
Effects of growth on lower incisor alignment
A
No predictors as to which pts would crowd and which would not. Late growth and adult growth is a contributor.
18
Q
Why do incisors crowd??
A
The MN grows forward or rotates upward, causing the lower incisors to be carried forward into the lip, the lip then tips the incisors lingually and crowds.
The MN Grows downward or rotates backward. Skeletal open bite. Incisors then tipped by lip pressure.
19
Q
What are the recommendations for retention to prevent lower incisor crowding?
A
Fulltime wear for 6 months, minimum retention for 12 months or until growth is completed.
20
Q
For long-term retention of lower incisors what is best?
A
Fixed.
21
Q
Hawley retainers
A
Modifications are possible.
22
Q
Wrap around retainers and Essixs
A
Hold tooth positions well and do not allow movement and PDL reorganization.
23
Q
Tooth Positioners
A
Bulky, poor cooperation. Limited correction of irregularities and of deep bite. Useful for finishing and can act as a functional appliance.
24
Q
Indications for fixed retainers
A
Intra-arch instability is anticipated, long term retention is planned. Avoids crowding due to late differential growth. Can be banded or bonded.
25
How do you maintain a closed diastema?
Bonded braided wire. Removable appliances ineffective for diastemas.
26
How do you maintain a pontic space?
Post abutment alignment. Allows reduction in tooth mobility for prosthetics. Intracoronal wire for posteriors. Pontic and bonded wire for anteriors.
27
Which is more reliable for maintenance of extraction space in adults? Fixed or removable?
Fixed. Removable must be worn consistently
28
What re active retainers used for?
To correct minor irregularities and then as a retention appliance.
29
Indications for modified functional appliances
Some growth left. No more than 3 MM slip to Class II. Changes made by tooth movement. Most teeth contact appliance for alignment retention.
30
When do you need retention?
After all ortho! Starts only after appliances removed.
31
What is the minimum ft retention and minimum retention?
FT: 3-6 months
Ret: 12+ months.
Until growth is completed.
32
What is the most common crowding to relapse?
MN incisors. Often required for lower incisors.
33
Why do we retain?
Changes in PD tissues following ortho. Effects of growth.
34
What are the types of retainers?
Removable, fixed and active.
35
What are the force requirements for initial alignment?
Direction: Provided by flexing the wire into the bracket.
Duration: Ideally longer, you want springiness in the wire.
Degree: Low, you want to minimize friction (2 mm of clearance). Wire shape helps determine.
36
What type of wire do you want for initial alignment?
It's for a long duration with a low force degree, with little friction. So you want a springy wire. NOT formable.
round, 2 mil clearance either stainless steel or NiTi.
37
What does the loss of the 1st molar result in?
M drifting and tipping of 2nd and 3rd molars. Leads to a loss of vertical dimension through extrusion of opposing teeth. Distal drifting of bicuspids. Stepped marginal ridges. Decreased perio health and altered gingival form. Mesial infrabony defect. Food impaction and difficulty in cleaning.
38
Why does a loss of the first molar result in a difficult restoration?
Unparallel abutments, excessive tooth preparation and risk of pulpal damage. Not enough pontic space, poor force distribution on PDL
39
What are the molar uprighting indications?
Tipped 2nd and 3rd molars. Good prosthetic prognosis. Ideally a class I or mild class III occlusion. Need posterior for vertical support and anterior teeth for anchorage and anterior guidance.
40
Why can you only have a tipped molar and not a rotated one?
Mesial root movement is very difficult and anchorage intensive. You can do mild ones, but not severe.
41
Why can you only have mild molar extrusion in uprighting?
As the molar tips it extrudes. You can do occlusal adjustments as the molar is uprighted.
42
Can mesially hooked roots be uprighted?
yes. but it is slower. You don't want small roots.
43
Why is knife edge bone in edentulous space a contraindication?
No mesial root movement possible. Bone is primarily cortical bone and mesial movement results in dehiscence and root resorption.
44
What skeletal relationships are difficult in molar uprighting?
Severe AP skeletal deviation and vertical skeletal relationships. Steep or flat mn planes.
45
What happens when you have a steep or flat MN plan and try molar uprighting?
Steep: open bite
Flat: very slow movement.
46
What is the normal vertical facial relationship?
Lower border of MN intersects with lower border of cranium.
47
Steep MN plane
Lower border of MN passes into cranium. Open bite, obtuse gonial angle, weak muscles of mastication. Too rapid of molar uprighting. Downward and backward rotation of MN.
48
Flat MN plane angle
Line passes below occiput.. Acute gonial angle. Skeletal deep bite. strong MOM. slow or difficult molar uprighting. Occlusal bite plane or reduction often required.
49
Why are cross bites contrainticated
You need a normal transverse reltaitonship.
50
How can you tell the difference between skeletal vs dental crossbite?
Skeletal: Narrow mx. Surgical corrrection.
Dental: Teeth tipped. corrected by orhto
51
Molar uprighting contraindications
Malocclusion, short or blunted roots, CO/CR discrepancy, mesial root movement required, poor oral hygiene or prosthetic prognosis.
52
How do you prepare a pt?
Making sure periodontal problems are in check
53
When should you reduce occlusion?
When there is no increase in vertical desired (steep MN plane) no molar intrusion is possible. To avoid occlusal interference.
54
When shouldn't you reduce occlusion?
You want to increase vertical or you want to intrude.
55
How do you intrude?
Arch wire, occlusal forces, skeletal anchorage.
56
What do anterior bite planes do?
Avoid occlusal trauma on molar. Increases VDO. Molar uprights and extrudes. Rotates mn down and back, increasing class II relationship. Not indicated for steep MN plane.
57
Removable appliances for Molar uprighting
Tipping only. Less control. Needs high degree of cooperation. Easy mechanics. Less expensive. Less chair time. Normal oral hygiene.
58
Fixed appliances for molar uprighting.
tipping, sliding and bodily movement. More control (3 planes). Less cooperation.. Mechanics more complex. Expensive. Hygiene is more difficult.
59
Where should the force be for uprighting/tipping
Tipping force needs to be above the center of resistance.
60
Where should the force be for bodily moving?
At center of resistance.
61
Indications for removable appliances
Tipping is less than 20. Not enough anchorage. Compliant pt.
62
Vertical Helical Spring Appliance
Need enough vestibular depth. Hard to put in. Produces tipping with normal extrusion
63
Recurved Helical Spring
Requires adjustment skills. Up to 4 mm of tipping. Best if bicuspids are present. Tipping and normal extrusion
64
Split saddle spring
Activated by opening loops. Broad cantact area. Can activate 2-3 mm. Most effective if tooth tipped recently. Produces tipping and normal extrusion.
65
Sling shot appliance
Least control. Force supplied by elastic band that must be changed daily. Direct bonded hook or ledge.
66
Indications for fixed appliances
Tipped up to 60 degrees. Need adequate anchorage. Need greater control. Need training and operator skillz.
67
Minimum anchorage?
cupid and 2 biscuspid. The greater the anchor unit the better. Force on anchor unit pushes cuspid and bicuspids apically and labially.
68
Better anchorage
Cuspid to cuspid lingual arch.
69
How do you improve anchorage
Bond to each incisor
70
What is the greatest anchorage?
Molar to molar. Useful for bodily movement of bilateral uprighting.
71
Simple anchorage
Bonded wires to teeth. Cuspids and bicuspids, with lingual anchorage wire bonded to molar tube. very secure. Prevents individual tooth movement. Inexpensive. Can't move anchor teeth-disadvantage.
72
What do you do with 3rd molars?
Use as anchorage. Extract-no opposing tooth following uprighting, distal movement is required, or after treatment if used as anchorage unit.
73
Stage 1 goal
Archwire engagement. Remove rotations and level occluso-gingivally anchor unit. Not needed if teeth are well aligned, or no need to align anchor unit.
74
Wire for stage 1
Light, resilient wire. Super flexible ni ti or braided.
75
Stage 2
Upright molar and space closure.
76
Stage 2 wire
Larger, less resilient wire. .016 or .018 stainless steel wire.
77
What do you use to close the space in stage two?
Alastik chains, coil springs, or closing loops.
78
What do you use to upright molar in stage 2
Edgewise wire with loops.
79
Sheperd's Hook uprighting spring
Simplest of fixed appliances. Hook engages anchor unit. Least control. Allows BL movement and extrusion. ONLY FOR DISTAL TIPPING.
Cantilivered beam
80
Open Coil spring appliance
Indications: distally drifted bis. Tipped molar, reciprocal force.
round or small edgwise wire. Need to include incisors to avoid crowding and labial movement.
81
Uprighting spring
Grater control, molar intrusion or BL movement. Requires edgewise wire. Used as segmental or continuous archwire.
82
Closing loop
Close molar space and mesial root movement. Open loop for activation. Closure force moves molar. Lot's of stress on the anchors.
83
Tie-back wit hshepard's hook
Molar tipped against bi. mesial root movement desired. Ties molar to anchor to resist distal molar crown movement. Lot's of stress on the anchors.
84
Full lower appliances
Crowding, rotations, cross bites, bilateral uprighting, molar intrusion, mesial molar movement (cuz u don't wanna move the anchor unit distally)
85
Stage 3
Finishing. Finalizing molar uprighting. Leveling of marginal ridges, improving occlusion. Vertical elastics settle occlusion
86
Treatment time
Tipping only with normal mn plane: 6-12 months
| Complex: 12-24+ months
87
Retention for molar uprighting
Important to do within 24 hours. Relapse is very quick. Wait 3-6 months before prosthesis (can't get good impressions because of mobility). Allows for settling of occlusion--active stabilization
88
Hawley retainer
can add replacement teeth., centric stop, holds changes in other areas too.
89
Bonded wire
ssw. step down in space. very stable. little compliance needed, but no centric stops.
90
Intracoronal wire or bar
Heavy wire or bar. Occlusal preparation required. Stable. centric stops.
91
Temporary prosthesis
Preps at debanding, immediate temp insertion. Good centric stops. Must avoid prematurities. Maintain for 3-6 months
92
When do you evaluate need for oseous surgerY?
Only after 3 months. Need to allow for bone calcification. If you do it too early, you lose immature and crestal bone.
93
Advantages of molar uprighting
Normal axial incliniation, occlusal force distribution, perio prognosis, ideal prosthesis.
94
What is the easiest type of movement?
Extrusion. Because there is only tension on the PDL, and no bone resorption usually required.
95
How much force do you use in extrusion?
20-30 grams.
96
Where does the pathology or fracture need to occur in order to indicate extrusion?
Coronal 1/3 of root.
97
What are the other treatment options other than extrusion?
Extraction or osseous surgery.
98
Cons of osseous surgery
Crown lengthening, esthetics, loss of bone from adjacent teeth.
99
What are the indications for extrusion?
Fractures or pathology in coronal 1/3. Isolated periodontal defect. Teeth gingival to plane of occlusion with adequate space.
100
Contraindications for extrusion
Pathology, poor hygiene, too short of root, furcation exposure, poor endo, perio conditions that require surgery, tooth has no strategic value, pt. doesn't want treatment.
101
Extrusion treatment objectives
Create adequate tooth for restoration with fracture/path within the restoration while maintaining biologic width.
102
Extrusion advantages
Saves a tooth, bone is conserved, gingival contours maintained, don't have to mess with adjacent teeth, good esthetics, maintains biologic width, improved crown to root ratio, more occlusal/incisal margin and prep.
103
Extrusion disadvantages
Appliance wear, increased treatment time, complexity and cost, post extrusion perio surgery, narrower root (MD) after extrusion.
104
Steps of extrusion
Determine prognosis
Prepare tooth (endo, temp crown)
Place attachement on tooth (restorative pin angled gingivally or bonded hook)
Establish anchorage unit and determine extrusion distance.
Extrude the tooth using elastic.
Stabilize the tooth using tie or composite resin for 1 month prior to surgery.
Perio surgery one month after completion of movement to make levels of bone and gingiva equal relative to adjacent teeth.
Remove appliance and prepare tooth for prosthesis. No retention required.
105
How big should the anchorage unit be?
2 teeth on either side unless it is a molar. Rectangular wire with loop as attachment.
106
What is extrusion distance?
Distance between pin and wire. Built into appliance by height of wire placement.
distance to alveolar crest + BW = distance margin is above the sulcus base.
107
How fast can you extrude?
Light force extruding 1-1.5 mm/week. Weekly appt necessary.
108
What are the categories of space management?
Space maintenance: Space predicted is adequate
| Space regaining: Space predicted is deficient.
109
Space maintenance
Prevent loss of space from premature loss of primary teeth and drifting associated with leeway space.
110
Space regaining
Localized space loss. Complexity is moderate is less than 3 mm. Severe if greater than 3 mm.
111
How does incisor position affect space loss treatment?
No protrusion, you can expand. But if there is incisor protrusion, it is much more complex and extractions are possible.
112
Why would you space maintain?
Early loss of a primary second molar to prevent drift and posterior crowding. Early loss of first molar or canine to prevent drift of anterior teeth. When space analysis predicts no discrepancy between space available and space required to prevent loss of leeway space.
113
When do you use band and loop?
SINGLE missing primary molar with teeth on both sides of space. Can only replace 1 tooth.
114
When do you use the distal shoe?
SINGLE missing primary second molar before the eruption of the permanent molar. Contraindicated for pt. who are at risk for subacute endocarditis or if immunocompromised.
115
When do you use a lingual arch?
Missing multiple primary posterior teeth. Permanent incisors have erupted. Used to prevent mesial drift of permanent molars. Can add a soldered spur to hold anterior teeth.
116
When do you use a Nance appliance or TPA?
Lingual arch for the MX. To derotate molars.
117
When do you use a partial denture?
Multiple missing teeth per segment and permanent incisors haven't erupted. Replaces function. Requires compliance. Soft tissue irritation is a problem.
118
When is a tooth over-retained?
If a primary tooth remains after 3/4 of the root of the permanent tooth has formed. Teeth usually emerge when 3/4 of their roots are completed.
119
How do you manage over-retained teeth?
Extraction! If not, it can lead to gingival inflammation, hyperplasia, pain, bleeding, deflected eruption path or permanent tooth.
120
How should you manage ankylosed primary teeth?
Maintain until interference with eruption or drift of other teeth then extract and place space maintainer. If successor is not present, extract early, allowing other teeth to drift into edentulous space.
121
What are the issues with a permanent successor not present and an ankylosed tooth
Can develop a large vertical bony defect.
122
Problems with ectopic eruption
Cause resorption of wrong primary tooth or of another permanent tooth.
123
How do you manage unilateral lateral incisor ectopic eruption?
1. Space analysis to get big picture.
| 2. Reposition and hold.
124
How do you manage bilateral lateral incisor ectopic eruption?
Incisors can tip to lingual reducing circumference.
| Space analysis. May need to expand.
125
How do you manage MX molar ectopic eruption?
Observe for 6 months as self correction usually happens. If it doesn't, move the permanent tooth away from the resorbing tooth or use brass wire or separator. If very severe, can used fixed appliance or extract primary molar and manage space loss.
126
Problems caused by MX canine ectopic eruption
Impaction and resorption of the permanent lateral incisor roots.
127
When is there a good chance of normal eruption path for MX canine ectopic eruption?
If overlapping 1/2 of root of lateral incisor.
128
What are possible problems with crossbites?
Dental compensations. Unusual wear. Crowding.
129
How do you manage unilateral crossbite?
If associated with MN shift due to interference by primary canines, reshape and extract the primary canines.
If unilateral due to intra-arch asymmetries, reposition individual teeth.
130
How do you manage a bilaterally constricted MX and subsequent MN shift.
Expand MX. Wait to include permanent molars if expected within 6 months.
131
What are possible problems with anterior crossbites?
Esthetics, function, wear, perio
132
How do you manage anterior crossbites due to crowding?
Make space and monitor for self-correction as teeth erupt. You can extract primary teeth, slenderize, ortho space opening. If overbite is present, make space then tip with removable or fixed.
133
What happens with thumb sucking?
Openbite, excessive overjet, posterior crossbite.
134
How long do you need to suck your thumb in order to contribute to malocclusion?
6 hours per day!
135
When should you be concerned with oral habits?
When nearing eruption of permanent incisors at about 6 years.
136
What type of motivation do you need get a child to have to quit oral habits?
Internal! Child needs to want it.
137
What are the management strategies once you have internal motivation?
Reminder, reward and cemented reminder.
138
What is normal crowding for deciduous dentition?
Spacing is normal, crowding or lack of spacing is abnormal (usually indicates future crowding)
139
Which directions do incisors develop?
Develop and erupt to lingual.
140
In mixed dentition, what is normal incisor crowding?
2 mm. Usually resolves in 1-2 years with no treatment.
141
What is the most common cause of crowding?
Inadequate jaw size.
142
Causes of crowding
Inadequate jaw size, preamature loss of deciduous molars (spacemaintainer, good caries control)
Loss due to caries.
Constricted or narrow dental arches. (Mouth breathing.)
Oversized stainless steel crowns (only apparent crowding)
Tooth size discrepancy between MX and MN teeth (peg laterals)
Ankylosed deciduous teeth.
143
What are the functions of deciduous teeth?
Esthetics, chewing and space holding.
144
What is considered mild crowding in mixed dentition?
Less than 4 mm.
145
Possible treatment of mild crowding?
Disking deciduous teeth, lingual arch, fixed appliances to align.
146
How do lingual arches work?
Advance arch to move incisors anterior. Or hold arch to preserve leeway space.
147
How much do you need for the leeway space?
2.5 mm per side in the MN arch and 1.5 mm perside in the MX arch.
148
How much is moderate crowding?
approx 4-8 mm. Refer!
149
Treatment of moderate crowding?
Headgears/expanders. Removable appliances. Fixed lingual arches. Lip bumpers. Lateral expansion. braces
150
When is lateral expansion a suitable treatment?
Moderate crowding. Expand both MX and MN. Called Arch development.
151
How much is severe crowding?
greater than 8 mm. Need full work up.
152
What are the signs of severe crowding?
Premature exfoliation of deciduous canines as permanent lats erupt. Abnormal crescent resorption on mesial of deciduous canines.
Midline shift with blocked out lateral permanent incisor. Gingival recession present on labially placed incisors. Permanent canines labially placed or impacted. Prodtrusive incisors. Ectopically erupting permanent first molars. Vertical palisading of MX molars. Impacted 2nd molars.
153
What are the two severe crowding treatments?
Extraction vs. Non-extraction.
154
Extraction treatments for severe crowding
Serial extraction, first bis, 2nd bis, lower incisor, molar.
155
Non extraction treatment for severe crowding
AP expansion (incsiors to labial), lateral expansion, stability, lip support.
156
How does face height play a role in extractions for severe crowding?
Long face=extraction.
| Short face=rarely extractions.
157
What is serial extraction?
Removal of selected deciduous teeth leading to the removal of permanent teeth. Used when bicuspid extraction is indicated.
158
What is the order of serial extractions?
Removal of MX and MN deciduous cuspids (uncrowds incisors and slows down cuspid eruption), removal of MX and MN deciduous 1st molars (encourages early eruption of 1st bis. Removal of MX and MN first bis. Fixed ortho treatment to align and finish.
159
What are the effects of serial extractions?
Incisors upright lingually, decreasing protrusion (which is favorable only if incisors are protrusive), increases overbite, decreases the cuspid width, meseal movement of molar and second bicuspid, flattening of lips in profile
160
What directions does the space close from in serial extractions?
60% from distal and 40% from anterior.
161
Serial extractions diagnostic indications
Significant crowding (8-10 mm), incisors normal or protrusive, Class I posterior occlusion, Overbite normal to mild open, Normal face, jaw relations and growth.
162
Advantages of serial extraction
Teeth align as they erupt, teeth not expanded to align (cuspid width), cuspids erupt into line of arch, length of ortho is often reduced.
163
Disadvantages of serial extractions
Full ortho work up, removal of deciduous cuspids result in decreased arch length and cuspid width, difficult to predict jaw growth, requires follow up ortho, takes years of follow up, no advantage in long term stability.
164
Do midline diastemas close after cuspid eruption?
If less than 2 mm, yes. If 3 mm or more, less likely.
165
What causes spacing?
Incisor protrusion, labial tipping, missing permanent teeth, missing 2nd premolar,
166
What are some strategies for the missing 2nd premolar?
Retain deciduous molar. If lost early, plan for replacement tooth: Hold space, resin bonded bridge, implant--when growth is complete. Early extraction of 2nd deciduous molar, allowing permanent molars to tip and drift, then closing spaces orthodontically. MX anterior frenum. Tooth size discrepancies (peg lateral), tooth size/jaw size discrepancies. Weak cheek/lip musculature,
167
What are the options for missing lateral incisor
Deciduous lateral retention (not that great, too small), Cuspids erupt into lateral space, make it look like a lateral, or move cuspid distally and replace lateral. Dental implant. supernumerary teeth. Increased vertical overlap of incisors (closing diastema requires correcting depth of bite)
168
How do you correct an increased vertical overlap of incisors when lip display is normal?
Short or normal face height: allow for eruption of posterior teeth, then close spaces.
Long face hight: Intrude lower incisors, then close spaces.
169
How do you correct an increased vertical overlap of incisors when lip display is excessive?
Intrude MX anterior teeth, then close spaces.
170
Wire composition, shape and size for initial alignment?
NiTi, round, small. Don't need a wire with good formability. Springiness!
171
When would you use an alternate approach for initial alignment?
When the flexible continuous archwire would likely cause unwanted tooth movement and arch deformation.
172
How do you distinguish between a skeletal and dental crossbite?
In skeletal the bones are too narrow. If the dentoalveolar proccess leans inward, then it is dental. If the MX teeth lean outward, but are nevertheless in a crossbite, then it is skeletal.
173
When would you use a jackscrew?
For skeletal crossbite, nearly 100% effective before 15 years old.
174
When would you use a jackscrew with a bite block?
For skeletal crossbite. The block controls the tendency for bite opening and downward/backward rotation of the MN. Consider in long faced pt.
175
When would you use a jackscrew with surgical assistance?
Skeletal with too much sutural interdigitation to allow for a non-surgical palatal expansion. Normal used after 15 years of age.
176
When would you use just the surgical procedure for expansion?
Skeletal with too much interdigitation. If you are performing orthognathic surgery for some other malocclusion.
177
When would you use a heavy labial archwire?
For dental crossbite
178
When would you use a quad helix or W expander?
Dental crossbite, but also for skeletal crossbite in early mixed dentition.
179
When would you use crossbite elastics?
Dental. You have to take into accound the vertical componenet of elastics.
180
Skeletal, early mixed crossbite?
Quad helix, W-arch
181
Before 15, skeletal crossbite?
Jackscrew
182
After 15 yo skeletal crossbite
Consider surgical assisted or surgery
183
What do you use for dental crossbite?
Labial archwire, quad helix, w-arch, or cross elastics
184
What are the different methods of attachment?
Bonding to the crown, wire ligature, placing a pin.
185
Wire ligature
Leads to a loss of attachment.
186
What is the preferred method of attachment?
Bonding.
187
Placing a pin as method of attachment
Leads to a loss of tooth structure
188
What do you want the impacted tooth to erupt through?
Attached gingiva!
189
How can you tell if a pt. needs a frenectomy?
Not reliably through looking or blanching. Best is to close space, hold for more than 6 months and release. If it reopens, frenectomy is needed.
190
What order should you do a frenectomy in? Close teeth first? or close first?
Close first, then surgery. If you do the surgery first, scar tissue can impact space slosure.
191
If your pt. has a deep overbite and a greater than normal curve of spee, what are treatment options?
Intrude the anterior teeth or extrude the posterior teeth.
192
How do you decide whether or not to intrude or extrude?
Extrusion: if not growing, MN will rotate down and back, so best if pt. face is short and slight tendency toward class III. If growing, the result will be relative intrusion.
193
How do you intrude the anterior teeth?
Control force level carefully. Segmnetal and stiff wires in posterior.
194
Which pt. with deep bites should have intrusion of the anterior teeth?
Excessive incisor display not associated with short upper lip. If minimum vertical growth is expected and it is necessary to maintain lower face height.
