LONG TERM EFFECTS OF ORTHODONTIC
TREATMENT

INDIAN DENTAL ACADEMY

Leader in continuing dental education
www.indiandentala...
Introduction

www.indiandentalacademy.com
• The concept of evidence-based dental

care has become prevalent in recent
years.
• Consumers and policy makers seek
qual...
• In the late 1980s, the poor quality of the

knowledge base in orthodontics was
highlighted, with clinical decisions base...
• In particular, there have been no reports
from population-based prospective
longitudinal studies on the long-term
outcom...
• The long term outcomes of orthodontic treatment
•
•
•
•
•
•

in a population should be evaluated on the basis
of the
Dur...
• Effectiveness is achieved when persons

who receive the treatment experience a
significantly better overall clinical out...
• Investigating the safety of orthodontic

treatment should involve determining the
nature and extent of any short- or lon...
CLASS II CORRECTION

Orthopedic
appliances
CLASS III CORRECTION

Temporomandibular
joint

INTERNAL
DERANGEMENT
JOINT SOUND...
•Orthognathic surgical
procedures
•Periodontal tissues
•Profile changes in
extraction and non
extraction cases

Single jaw...
Arch length

•Arch form
considerations

Arch perimeter
Arch width
Arch expansion

•Retention and stability

www.indiandent...
Long term effects of orthopedic
appliances

Two phase treatment

One phase treatment

www.indiandentalacademy.com
• A popular strategy for treatment of skeletal
Class II malocclusions has been to initiate a
first," "initial," or "early"...
• A recent randomized clinical trial (Tulloch FC,
Proffit WR; Phillips SC AJO 2004) of early
Class II treatment has challe...
• Following phase 2 of the trials of Tulloch

and coworkers, it appears the benefits of
early treatment are lost and there...
• The study concluded that two-phase

treatment started in the mixed dentition
may be no more clinically effective than
on...
• Clinical trials by Ghafari et al (AJO1998)

•

comparing headgear treatment with the Frankel
appliance in children with ...
• Bowman(AJO 1998 ) stated that the

"perceived benefits unique to early
functional jaw orthopedics tend to
evaporate over...
• Several studies have reported anteroposterior
•
•

relapse resulting largely from dento alveolar
rebound in the period f...
• Thus possibly suggesting that long-term

stability of the treatment result is best
attained when orthopedic correction t...
Need for retention

www.indiandentalacademy.com
• The larger the orthopedic correction

achieved, the greater the likelihood that
postfunctional orthopedic relapse will
o...
• In the clinical trials of Wheeler and

coworkers, (AJO 2002) one year after
completing phase I, a greater proportion of
...
• Wheeler and Coworker suggested that an
improved retention scheme may be more
successful in retaining dental correction.
...
CLINICAL SIGNIFICANCE
(Dermaut LR et al AJO 1996 and
Pancherz H et al EJO 1990
• Long-term evaluations of growth after

ap...
• If there is an interval of time between the initial

•

phase of orthopedic treatment and the final
phase of fixed appli...
• Orthopedic retention may be instituted at

night for as long as 2 to 5 years.
• Retention is even more important in thos...
• Since the majority of post treatment

occlusal changes occur during the first 6
months post treatment, and are for the
m...
• Accordingly, it may be prudent to continue with

•
•

orthopedic forces until after at least 2 to 3 years
after peak hei...
• Modern "Truisms" as a Rationale for

Orthopedics and Orthopedic Retention
William A. Wiltshire and Susan Tsang
Seminar i...
• Based on current literature the authors believe that

it may be presently concluded that:
I. Functional orthopedic grow...
4.An orthopedic growth modification phase

appears to delay growth but after appliance
withdrawal, the maxilla and mandib...
6. Treatment should start in the late mixed
or early permanent dentition
corresponding to the pubertal growth
peak.
7. R...
8. Growth modification success is

multifactorial and can be related to many
issues (biologic, appliance, patient, and
pr...
• Long term effects of functional appliance
for class III correction

CHIN CUP

MAXILLARY
PROTRACTION
DEVICES

www.indiand...
• Sugawara J, et al AJO 1990 did a study to

•

investigate the long-term changes in the skeletal
Class lll profile subseq...
• A group that started at 7 years of age (n =
23), a group that started at 9 years of age
(n = 20), and one that started a...
• The results of the study were as follows:
• (1) The mandible showed no forward growth
•

•

during the initial stages of...
• In conclusion, the skeletal profile was

greatly improved during the initial stages
of chincap therapy, but such changes...
EFFECT OF MAXILLARY
PROTRACTION (Sung et al AJO
1998)

www.indiandentalacademy.com
• To further evaluate the effect of maxillary

protraction on facial growth, cephalometric
changes in 129 subjects with co...
• The control subjects had Angle Class I

malocclusions with normal overjet and
overbite. More maxillary forward
displacem...
• When changes due to treatment according
to ages were compared, there was no
statistical difference.
• The direction of m...
• The changes in skeletal profile, although

they represent significant improvement in
the younger children, are not maint...
Effect of orthodontic treatment
on TMJ

www.indiandentalacademy.com
• Studies from mid 1960s onwards
• Two studies were done as part of a

National Institutes of Dental Research
(NIDR) contr...
• Sadowsky and BeGole reported on the

findings from 75 adult subjects who were
treated with full fixed appliances as
adol...
• Findings were
• prevalence of symptoms varying between 15%
•
•

to 21% and 29% to 42% for signs ( joint sounds),
there w...
• According to Thompson faulty intercuspation of
•
•

the teeth and dental extrusions into the freeway
space are two of th...
Clinical significance
• If the condyles are not growing upward

and backward at the time of orthodontic
tooth movement, th...
• Additional condyle growth after other facial

growth has stopped is a special concern
because it can alter the occlusion...
• Dibbets and van der Weele reported the

findings from their prospective longitudinal
study in the Netherlands over a 15-...
• They evaluated subjectively perceived
•
•
•

symptoms, which increased from 20% to 62%;
Objectively identified clicking/...
• The influence of age disappeared after 10
years. For the first 10 years there was no
difference between the three treatm...
• Clicking frequency, subjective or objective,
was always higher in the four premolar
extraction group even before treatme...
CLINICAL SIGNIFICANCE

www.indiandentalacademy.com
• William E. Wyatt,reported
• In Class ll malocclusions with deep interlocking

•

cusps headgear and/or Class II elastics...
• Midline switch or cross elastics have a more

•

subtle effect. As the jaw is pulled to one side,
distal pressure is put...
• If there is a developing problem, it is better

to have the patient wear lower or reverse
headgear and Class III elastic...
Condyle fossa relationships

www.indiandentalacademy.com
R S Nanda & Carlton 2002 conducted a
follow-up prospective longitudinal study
to determine what changes occurred in
the co...
• There was no statistically significant

correlation between changes in the
condyle/fossa relationship based on age,
gend...
Clicking sounds and orthodontic
treatment

www.indiandentalacademy.com
• clicking is generally benign and does not
progress to more serious clinical
dysfunction or disease, even in subjects
who...
• Joint sounds alone are not characteristics

of disease and may be present for up to
10 years without progression.
• Join...
• If painful symptoms arise during

orthodontics, therapy may have to be
modified, gross occlusal interferences
relieved, ...
• Inger Egermark, Magnusson,. Carlsson ,

(EJO 1981) 20-Year Follow-up of Signs
and Symptoms of Temporomandibular
Disorder...
• 402 randomly selected 7-, 11-, and 15-

year-old subjects were examined clinically
and by means of a questionnaire for s...
• The oldest age group, 35 years of age, was
•
•

invited to a clinical examination, and 100
subjects were examined.
The c...
• Subjects with malocclusion over a long

period of time tended to report more
symptoms of TMD and to show a higher
dysfun...
• There were no statistically significant

differences in the prevalence of TMD
signs and symptoms between subjects
with o...
• This 20-year follow-up supports the

opinion that no single occlusal factor is of
major importance for the development o...
Long term effects of orthognathic
surgical procedures

www.indiandentalacademy.com
The Hierarchy of Stability and
Predictability
• Stability after surgical repositioning of the jaws
•
•
•
•
•

(in that ord...
• It is interesting to note that the key procedures in

•

surgical treatment of Class II problems superior
repositioning,...
• The most stable orthognathic procedure is

•

superior repositioning of the maxilla, closely
followed by mandibular adva...
• In the treatment of Class III patients, the maxilla
•
•

remains just where it was put in about 80% of
the patients, and...
• Surgical widening of the maxilla is the least

•

stable of the orthognathic surgical procedures .
Widening the maxilla ...
• Surgically-assisted rapid palatal

expansion (SARPE) appears to improve
stability and is preferred if only expansion
is ...
www.indiandentalacademy.com
Factors affecting the stability of
orthognathic surgical procedures
• Three principles that influence

postsurgical stabil...
PRINCIPLE 1
• Stability is greatest when soft tissues are relaxed during

•

•

the surgery and least when they are stretc...
• The least stable orthognathic surgical

procedure, widening the maxilla, stretches
the heavy, inelastic palatal mucosa

...
PRINCIPLE 2
• . Neuromuscular adaptation is essential

for stability. Fortunately, most orthognathic
procedures lead to go...
• This controls any tendency for the maxilla to

•

immediately relapse downward, and contributes
to the excellent stabili...
• In contrast, neuromuscular adaptation does not

•
•

occur when the pterygomandibular sling is
stretched during mandibul...
PRINCIPLE 3
•Neuromuscular adaptation affects muscular
length, not muscular orientation.
•If the orientation of a muscle g...
• This concept is best illustrated by the

effect of changing the inclination of the
mandibular ramus when the mandible is...
• The same is true, in reverse, when the

mandible is set back: major cause of
instability appears to be the tendency at
s...
• Although most patients are quite stable long•

•

term and average changes are small.
However long term follow up studie...
• At 5-year recall, bony changes associated with

•

shortening of the condylar processes (which
may not be associated wit...
• It has not been determined why a few

patients are susceptible to long-term
changes. It is important to continue to
foll...
Soft tissue after surgery
• The success of orthognathic surgery relies on

predictable skeletal and soft-tissue movements
...
• There are three distinct possibilities for long-term
•
•
•

soft tissue changes in surgically treated patients:
(1)resol...
Soft tissue changes due to aging
• soft tissue changes are obvious. Significant

typical changes include thinning of the l...
• In males the profile straightens and the lips
•

become more retrusive, the nose increases in
size in all dimensions, an...
• From the stability studies at UNC over the past

•

decade, it appears that the pattern of change
with Class III treatme...
Long term soft tissue changes due
to orthognathic surgery

www.indiandentalacademy.com
L’Tanya J. Bailey; Amy Joslin
Dover; William R. Proffit
AO 2007
• The purpose of the current investigation
was to compare ...
• When soft-tissue changes in Class III patients

•

are compared with the typical changes in
untreated adults, it was int...
• Beyond 1 year postsurgery, there also

was less flattening of the lips in the
surgery patients than would have been
expe...
• The Class III patients are less stable

during the first year but show fewer
changes in hard tissue measurements
beyond ...
• In general, skeletal Class III patients who

were treated with orthognathic surgery
experienced minimal change in soft
t...
• The orthodontics-only patients showed the
facial soft tissue changes that are typical
of aging in untreated individuals,...
CONCLUSION
• It can be concluded that successful results
can be attained with proper diagnosis and
treatment planning in c...
REFERENCES:-

• 1. Ghafari], Shofer FS, Jacobsson-Hunt U, et

al:-- Headgear versus function regulator in the
early treatm...
• 3. Bowman SJ:-- One-stage versus two-stage

treatment: are two really necessary? Am J
Orthod Dentofacial Orthop 1998 ;11...
5. Dermaut LR, Aclbers CM:---Orthopedics in orthodontics:
6.
7.
8.

fiction or reality. A review of the literature-part II...
9. Sugawara J, Asano T, Endo N, Mitani H.--

Long-term effects of chincap therapy on
skeletal profile in mandibular progna...
12. Sadowsky C, Polson AM. Temporomandibular

disorders and functional occlusion after orthodontic
treatment: results of t...
15. Egermark-Eriksson I, Carlsson GE, Ingervall

B.--- Prevalence of mandibular dysfunction and
orofacial Para function in...
17. Van Sickels JE, Richardson DA. Stability of

orthognathic surgery: a review of rigid fixation.
Br J Oral Maxillofac Su...
Thank you
www.indiandentalacademy.com
Leader in continuing dental education

www.indiandentalacademy.com
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Long term effects of orthodontic treatment /certified fixed orthodontic courses by Indian dental academy

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The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and offering a wide range of dental certified courses in different formats.

Indian dental academy provides dental crown & Bridge,rotary endodontics,fixed orthodontics,
Dental implants courses.for details pls visit www.indiandentalacademy.com ,or call
0091-9248678078


The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and offering a wide range of dental certified courses in different formats.


Indian dental academy provides dental crown & Bridge,rotary endodontics,fixed orthodontics,
Dental implants courses.for details pls visit www.indiandentalacademy.com ,or call
00919248678078

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Long term effects of orthodontic treatment /certified fixed orthodontic courses by Indian dental academy

  1. 1. LONG TERM EFFECTS OF ORTHODONTIC TREATMENT INDIAN DENTAL ACADEMY Leader in continuing dental education www.indiandentalacademy.com www.indiandentalacademy.com
  2. 2. Introduction www.indiandentalacademy.com
  3. 3. • The concept of evidence-based dental care has become prevalent in recent years. • Consumers and policy makers seek quality, value for money, and measurable benefits from oral health care, and orthodontic care is no exception. www.indiandentalacademy.com
  4. 4. • In the late 1980s, the poor quality of the knowledge base in orthodontics was highlighted, with clinical decisions based upon low-level information from case reports, case series, cross-sectional studies. • Although there have been improvements since that time, there is still a shortage of evidence from studies that have evaluated orthodontic treatment. www.indiandentalacademy.com
  5. 5. • In particular, there have been no reports from population-based prospective longitudinal studies on the long-term outcome of orthodontic treatment. www.indiandentalacademy.com
  6. 6. • The long term outcomes of orthodontic treatment • • • • • • in a population should be evaluated on the basis of the Duration, Effectiveness, Efficacy, Safety Effort and Cost invested in orthodontic therapy www.indiandentalacademy.com
  7. 7. • Effectiveness is achieved when persons who receive the treatment experience a significantly better overall clinical outcome than those who do not. In other words, does the treatment actually work in the real world? www.indiandentalacademy.com
  8. 8. • Investigating the safety of orthodontic treatment should involve determining the nature and extent of any short- or longterm adverse oral health outcomes of having it. www.indiandentalacademy.com
  9. 9. CLASS II CORRECTION Orthopedic appliances CLASS III CORRECTION Temporomandibular joint INTERNAL DERANGEMENT JOINT SOUNDS CLICKING Condyle fossa relationship www.indiandentalacademy.com
  10. 10. •Orthognathic surgical procedures •Periodontal tissues •Profile changes in extraction and non extraction cases Single jaw surgery Double jaw surgery www.indiandentalacademy.com
  11. 11. Arch length •Arch form considerations Arch perimeter Arch width Arch expansion •Retention and stability www.indiandentalacademy.com
  12. 12. Long term effects of orthopedic appliances Two phase treatment One phase treatment www.indiandentalacademy.com
  13. 13. • A popular strategy for treatment of skeletal Class II malocclusions has been to initiate a first," "initial," or "early" phase of functional or headgear treatment for growth modification, followed by a "second," "subsequent," or "final“ phase of fixed appliance treatment. • The first phase aims to correct the skeletal Class II problem, while the second phase is aimed at dental detailing with full fixed orthodontic appliances. www.indiandentalacademy.com
  14. 14. • A recent randomized clinical trial (Tulloch FC, Proffit WR; Phillips SC AJO 2004) of early Class II treatment has challenged conventional dogma, reporting that early treatment had little effect on the subsequent treatment outcomes measured as skeletal change, alignment, occlusion of teeth, or length and complexity of treatment. www.indiandentalacademy.com
  15. 15. • Following phase 2 of the trials of Tulloch and coworkers, it appears the benefits of early treatment are lost and there are no significant differences between those who receive early treatment and those who do not, relative to anterior-posterior or vertical skeletal or dental measures, PAR scores, length of fixed appliance treatment, or need for extractions or orthognathic surgery. www.indiandentalacademy.com
  16. 16. • The study concluded that two-phase treatment started in the mixed dentition may be no more clinically effective than one-phase treatment started in the early permanent dentition. www.indiandentalacademy.com
  17. 17. • Clinical trials by Ghafari et al (AJO1998) • comparing headgear treatment with the Frankel appliance in children with varying dental ages did not find Class II correction to be influenced by timing of eruption of second premolars or molars, They suggested that the optimal time for early treatment corresponds to late childhood just before loss of the primary maxillary second molars, as mesial movement of the permanent molar can be prevented to favor correction of the distocclusion. www.indiandentalacademy.com
  18. 18. • Bowman(AJO 1998 ) stated that the "perceived benefits unique to early functional jaw orthopedics tend to evaporate over the long-term.”. • Although functional appliances may work, albeit unpredictably, their use represents a practice management decision, not a biological treatment imperative." www.indiandentalacademy.com
  19. 19. • Several studies have reported anteroposterior • • relapse resulting largely from dento alveolar rebound in the period following functional appliance treatment. In patients treated with the Herbst appliance, Ruf and Pancherz J (Semin Orthod, 2003) noted that relapse occurred particularly in cases treated before the pubertal peak. Relapse of the overjet or molar relationship occurred in 30% of prepeak Herbst patients but in only 8% of postpeak Herbst patients, www.indiandentalacademy.com
  20. 20. • Thus possibly suggesting that long-term stability of the treatment result is best attained when orthopedic correction takes place during the peak or early postpeak period when all permanent teeth are present to promote stable interdigitation of the occlusion.. www.indiandentalacademy.com
  21. 21. Need for retention www.indiandentalacademy.com
  22. 22. • The larger the orthopedic correction achieved, the greater the likelihood that postfunctional orthopedic relapse will occur • For this reason, a well-contemplated and efficient orthopedic retention protocol must be instituted to maintain the resultant dental and skeletal changes. www.indiandentalacademy.com
  23. 23. • In the clinical trials of Wheeler and coworkers, (AJO 2002) one year after completing phase I, a greater proportion of subjects “without retention following the orthopedic phase experienced relapse in comparison to a group that was retained with appliance wear on alternating nights for 6 months (42% vs 32%), although the difference was not statistically significant. www.indiandentalacademy.com
  24. 24. • Wheeler and Coworker suggested that an improved retention scheme may be more successful in retaining dental correction. • While the study of Tulloch and coworkers found the gains from early treatment are lost by the end of the fixed appliance phase, but their study design did not include a retention protocol for patients waiting for eruption of permanent teeth. www.indiandentalacademy.com
  25. 25. CLINICAL SIGNIFICANCE (Dermaut LR et al AJO 1996 and Pancherz H et al EJO 1990 • Long-term evaluations of growth after appliance therapy seems to suggest that the inherited growth patterns of the maxilla and mandible reappear and growth catches up to the amounts that would have occurred over time with normal growth and development without intervention. www.indiandentalacademy.com
  26. 26. • If there is an interval of time between the initial • phase of orthopedic treatment and the final phase of fixed appliance therapy while awaiting eruption of the complete permanent dentition, activators can be modified to accommodate erupting permanent teeth and may be continually worn until the start of phase 2 treatment. This protocol keeps the mandible in a protracted position and even if worn only at night, the neuromuscular response and growth stimulatory effect is maintained. www.indiandentalacademy.com
  27. 27. • Orthopedic retention may be instituted at night for as long as 2 to 5 years. • Retention is even more important in those patients who have not achieved a solid Class 1 molar relationship during phase I. www.indiandentalacademy.com
  28. 28. • Since the majority of post treatment occlusal changes occur during the first 6 months post treatment, and are for the most part of dental origin, a reliable retention appliance that can firmly hold the dental correction induced by functional orthopedics may be well advised. www.indiandentalacademy.com
  29. 29. • Accordingly, it may be prudent to continue with • • orthopedic forces until after at least 2 to 3 years after peak height velocity (PHV), approximately age 14 to 15 years for most girls and age 16 to 17 years for most boys. Late maturing individuals may require an even longer period. Although small increments of continued growth are seen until about 19 to 21 years for females and 21 to 25 for males, it is probably unreasonable to expect continued orthopedic retention until this age. www.indiandentalacademy.com
  30. 30. • Modern "Truisms" as a Rationale for Orthopedics and Orthopedic Retention William A. Wiltshire and Susan Tsang Seminar in Orthodontics, March, 2006: www.indiandentalacademy.com
  31. 31. • Based on current literature the authors believe that it may be presently concluded that: I. Functional orthopedic growth modification affects both skeletal and dentoalveolar structures, as well as the soft tissues of the face. 2. It is possible to achieve successful clinical improvement of Class II malocclusions with orthopedic growth modification. 3. The treatment effect of functional orthopedics disappear with time and appear to be more dentoalveolar rebound' than skeletal change . www.indiandentalacademy.com
  32. 32. 4.An orthopedic growth modification phase appears to delay growth but after appliance withdrawal, the maxilla and mandible appear to reestablish and catch up to their previous growth patterns. 5. The present delivery of Class II early treatments does not appear to reduce the average treatment time of full fixed mechanotherapy during a second phase. www.indiandentalacademy.com
  33. 33. 6. Treatment should start in the late mixed or early permanent dentition corresponding to the pubertal growth peak. 7. Retention protocols after phase I orthopedics are not currently effective and need to be more stringently implemented and for longer time periods to maintain corrections achieved during phase I. www.indiandentalacademy.com
  34. 34. 8. Growth modification success is multifactorial and can be related to many issues (biologic, appliance, patient, and provider), the predictors of which are not presently clearly delineated from a scientific point of view.  Further research is needed in this area. www.indiandentalacademy.com
  35. 35. • Long term effects of functional appliance for class III correction CHIN CUP MAXILLARY PROTRACTION DEVICES www.indiandentalacademy.com
  36. 36. • Sugawara J, et al AJO 1990 did a study to • investigate the long-term changes in the skeletal Class lll profile subsequent to chin cap therapy. The sample consisted of 63 Japanese girls who had skeletal Class III malocclusions before treatment. All underwent chin cap therapy from the beginning of treatment. The duration of chincap therapy varied but averaged 41/2 years. The samples were divided into the following three groups according to their ages when chincap therapy was started: www.indiandentalacademy.com
  37. 37. • A group that started at 7 years of age (n = 23), a group that started at 9 years of age (n = 20), and one that started at 11 years of age (n = 20). The data were derived from lateral cephalometric head films, taken serially at the ages of 7, 9, 11, 14, and 17 years.. www.indiandentalacademy.com
  38. 38. • The results of the study were as follows: • (1) The mandible showed no forward growth • • during the initial stages of chincap treatment in all three groups. (2) Patients who had entered treatment at 7 and 9 years of age appeared to show. a catch-up manner of mandibular displacement in a forward and downward direction before growth was completed. (3) There was no statistical difference in the final skeletal profile between the group that had entered treatment at age 7 and the one that had entered at age 11 www.indiandentalacademy.com
  39. 39. • In conclusion, the skeletal profile was greatly improved during the initial stages of chincap therapy, but such changes were often not maintained thereafter. • This finding indicated that chincap therapy did not necessarily guarantee positive correction of skeletal profile after complete growth www.indiandentalacademy.com
  40. 40. EFFECT OF MAXILLARY PROTRACTION (Sung et al AJO 1998) www.indiandentalacademy.com
  41. 41. • To further evaluate the effect of maxillary protraction on facial growth, cephalometric changes in 129 subjects with conditions diagnosed as skeletal Class III malocclusion and who had been treated with maxillary protraction were compared to 9 male and 12 female subjects with annual cephalometric records from the Yonsei growth study sample. www.indiandentalacademy.com
  42. 42. • The control subjects had Angle Class I malocclusions with normal overjet and overbite. More maxillary forward displacement and mandibular growth inhibition were observed in the protraction group during treatment, and the difference from the untreated controls was statistically significant. www.indiandentalacademy.com
  43. 43. • When changes due to treatment according to ages were compared, there was no statistical difference. • The direction of maxillary growth was similar in the untreated and protraction groups. Maxillary protraction had a growth-stimulating effect on the maxilla during the treatment period. www.indiandentalacademy.com
  44. 44. • The changes in skeletal profile, although they represent significant improvement in the younger children, are not maintained for a long period, in most cases. • This finding suggests that profiles have a tendency to return to their original shapes, which may have been predetermined morphogenetically. www.indiandentalacademy.com
  45. 45. Effect of orthodontic treatment on TMJ www.indiandentalacademy.com
  46. 46. • Studies from mid 1960s onwards • Two studies were done as part of a National Institutes of Dental Research (NIDR) contract on the long-term effects of orthodontic treatment. www.indiandentalacademy.com
  47. 47. • Sadowsky and BeGole reported on the findings from 75 adult subjects who were treated with full fixed appliances as adolescents approximately 20 years previously and compared them with a similar group of 75 adults with untreated malocclusions. www.indiandentalacademy.com
  48. 48. • Findings were • prevalence of symptoms varying between 15% • • to 21% and 29% to 42% for signs ( joint sounds), there was no statistically significant difference between treated and untreated subjects in either of the studies. The conclusion from the above two studies was that orthodontic treatment performed during adolescence did not generally increase or decrease the risk of developing TMD in later life. www.indiandentalacademy.com
  49. 49. • According to Thompson faulty intercuspation of • • the teeth and dental extrusions into the freeway space are two of the many etiologic factors that may lead to joint dysfunction and its sequelae. Dysfunction of the joints and musculature may occur before orthodontic treatment, during treatment, or anytime after treatment has been completed. Whether related directly to treatment or not, the orthodontist must be alert to recognize such dysfunction and intervene whenever it may occur. www.indiandentalacademy.com
  50. 50. Clinical significance • If the condyles are not growing upward and backward at the time of orthodontic tooth movement, the body of the mandible will not be projected downward and forward with the rest of the face, and the normal dental freeway space can be lost. The result is downward and backward rotation of the mandible, which may cause clicking and other symptoms in the joint. www.indiandentalacademy.com
  51. 51. • Additional condyle growth after other facial growth has stopped is a special concern because it can alter the occlusion and joint function. There may be no joint clicking or other symptoms at 12 or 14 years of age, yet pronounced symptoms 5 years later. www.indiandentalacademy.com
  52. 52. • Dibbets and van der Weele reported the findings from their prospective longitudinal study in the Netherlands over a 15-year period for 111 of the original 172 orthodontically treated patients of the average age of 12.5 years who were enrolled in the study. • Removable appliances (functional) were used in 39%, fixed appliances (Begg) in 44%, and chin cups in 17% of cases. A nonextraction approach was used in 34% of cases, four premolars were extracted in 29%, and other extractions in 37%. www.indiandentalacademy.com
  53. 53. • They evaluated subjectively perceived • • • symptoms, which increased from 20% to 62%; Objectively identified clicking/crepitation, which increased from 23% to 36% after 4 years and then stabilized; The radiographic appearance of the condyle, which increased slightly during the first 4 years and then stabilized at around 25%. It was found that during the first years of the study, age probably accounted for the statistical differences in percentages between the three types of treatment; www.indiandentalacademy.com
  54. 54. • The influence of age disappeared after 10 years. For the first 10 years there was no difference between the three treatment groups with regard to subjective clicking., after 15 years it was greater for the four premolar extraction group • Objective clicking was always more frequent in the four-premolar extraction group at all time points, www.indiandentalacademy.com
  55. 55. • Clicking frequency, subjective or objective, was always higher in the four premolar extraction group even before treatment was started. • They concluded that the original growth pattern, rather than an extraction treatment strategy, was the most likely factor responsible for the frequency of Chronic mandibular disorder reported many years post treatment www.indiandentalacademy.com
  56. 56. CLINICAL SIGNIFICANCE www.indiandentalacademy.com
  57. 57. • William E. Wyatt,reported • In Class ll malocclusions with deep interlocking • cusps headgear and/or Class II elastics are often used in an effort to get the patient into a Class I cuspal relationship. As the maxilla is moved backward, the muscles of mastication will attempt to retract the mandible when the patient closes in to maximum intercuspation. This compensating movement by the mandible can put distal pressure on the condyles and may cause an anterior dislocation of the disk www.indiandentalacademy.com
  58. 58. • Midline switch or cross elastics have a more • subtle effect. As the jaw is pulled to one side, distal pressure is put on one condyle only. If this creates a TMJ problem, midline elastics should be worn only during waking hours so that muscles can help to hold the mandible forward Lower headgears or reverse headgears that exert distal pressure on the chin and Class lll elastics are a very important part of orthodontic treatment, but they too can put distal pressure on the mandible.. www.indiandentalacademy.com
  59. 59. • If there is a developing problem, it is better to have the patient wear lower or reverse headgear and Class III elastics only during waking hours. • During this period lower or reverse headgears have little effect on the TMJ because muscle tone (tension) positions the mandible forward. www.indiandentalacademy.com
  60. 60. Condyle fossa relationships www.indiandentalacademy.com
  61. 61. R S Nanda & Carlton 2002 conducted a follow-up prospective longitudinal study to determine what changes occurred in the condyle/fossa relationship after treatment. With orthodontic treatment, the condyle became more concentrically positioned, www.indiandentalacademy.com
  62. 62. • There was no statistically significant correlation between changes in the condyle/fossa relationship based on age, gender, skeletal or dental variables, signs or symptoms of temporomandibular disorder, headgear use, type of elastics, or nonextraction vs extraction treatment. www.indiandentalacademy.com
  63. 63. Clicking sounds and orthodontic treatment www.indiandentalacademy.com
  64. 64. • clicking is generally benign and does not progress to more serious clinical dysfunction or disease, even in subjects who previously had symptoms., subjects with symptomatic clicking can be successfully treated without addressing the position of the disc www.indiandentalacademy.com
  65. 65. • Joint sounds alone are not characteristics of disease and may be present for up to 10 years without progression. • Joint sounds do not necessarily indicate a "problem" but may represent a "risk" factor; however, no treatment should be considered in the absence of symptoms. www.indiandentalacademy.com
  66. 66. • If painful symptoms arise during orthodontics, therapy may have to be modified, gross occlusal interferences relieved, and forces tending to distalize the mandible eliminated www.indiandentalacademy.com
  67. 67. • Inger Egermark, Magnusson,. Carlsson , (EJO 1981) 20-Year Follow-up of Signs and Symptoms of Temporomandibular Disorders and Malocclusions in Subjects With and Without Orthodontic Treatment in Childhood www.indiandentalacademy.com
  68. 68. • 402 randomly selected 7-, 11-, and 15- year-old subjects were examined clinically and by means of a questionnaire for signs and symptoms of TMDs. The examination was repeated after five and ten years. After 20 years, 320 subjects (85% of the traced subjects) completed the questionnaire. www.indiandentalacademy.com
  69. 69. • The oldest age group, 35 years of age, was • • invited to a clinical examination, and 100 subjects were examined. The correlations between signs and symptoms of TMD and different malocclusions were mainly weak,. Lateral forced bite and unilateral crossbite were correlated with TMD signs and symptoms at the 10- and 20-year follow-ups. www.indiandentalacademy.com
  70. 70. • Subjects with malocclusion over a long period of time tended to report more symptoms of TMD and to show a higher dysfunction index, compared with subjects with no malocclusion at all. www.indiandentalacademy.com
  71. 71. • There were no statistically significant differences in the prevalence of TMD signs and symptoms between subjects with or without previous experience of orthodontic treatment. www.indiandentalacademy.com
  72. 72. • This 20-year follow-up supports the opinion that no single occlusal factor is of major importance for the development of TMD,. • Subjects with a history of orthodontic treatment do not run a higher risk of developing TMD later in life, compared with subjects with no such experience . www.indiandentalacademy.com
  73. 73. Long term effects of orthognathic surgical procedures www.indiandentalacademy.com
  74. 74. The Hierarchy of Stability and Predictability • Stability after surgical repositioning of the jaws • • • • • (in that order of importance) depends on the Direction of movement, The type of fixation and The surgical technique, Neuromascular adaptation Enough data exist now to rank different jaw movements in order of stability and predictability www.indiandentalacademy.com
  75. 75. • It is interesting to note that the key procedures in • surgical treatment of Class II problems superior repositioning, mandibular advancement and their combination are quite stable. In Class III treatment, maxillary advancement is the most stable procedure, while downward movement of the maxilla and mandibular setback remain problematic. www.indiandentalacademy.com
  76. 76. • The most stable orthognathic procedure is • superior repositioning of the maxilla, closely followed by mandibular advancement in patients whom anterior facial height is maintained or increased. These procedures, the key ones in correcting severe Class II problems, can be considered highly stable even without rigid fixation, and this remains the case when they are combined in the treatment of patients with mandibular deficiency and a long face-but only if rigid fixation is used www.indiandentalacademy.com
  77. 77. • In the treatment of Class III patients, the maxilla • • remains just where it was put in about 80% of the patients, and there is almost no tendency for major relapse (>4mm). With rigid fixation, the combination of maxillary advancement and mandibular setback is acceptably stable. In contrast, isolated mandibular setback often is unstable. So is downward movement of the maxilla that creates downward backward rotation of the mandible. For this reason, almost all Class III patients now have maxillary advancement, either alone or (more frequently) combined with mandibular setback www.indiandentalacademy.com
  78. 78. • Surgical widening of the maxilla is the least • stable of the orthognathic surgical procedures . Widening the maxilla stretches the palatal mucosa, and its elastic rebound is the major cause of the relapse tendency. Strategies to control relapse include overcorrection initially and careful retention afterward, with either a heavy orthodontic archwire or palatal bar during the completion of orthodontic treatment and then a palate-covering retainer for at least the first post -surgical year. www.indiandentalacademy.com
  79. 79. • Surgically-assisted rapid palatal expansion (SARPE) appears to improve stability and is preferred if only expansion is required, but this is not an attractive alternative if a second surgery then would be needed for ant-post or vertical change in the position of the maxilla. www.indiandentalacademy.com
  80. 80. www.indiandentalacademy.com
  81. 81. Factors affecting the stability of orthognathic surgical procedures • Three principles that influence postsurgical stability help to put this in perspective: www.indiandentalacademy.com
  82. 82. PRINCIPLE 1 • Stability is greatest when soft tissues are relaxed during • • the surgery and least when they are stretched. Moving the maxilla up relaxes tissues. Moving the mandible forward stretches tissues, but rotating it up at the gonial angle and down at the chin decreases the amount of stretch. It is not surprising that the most stable mandibular advancements rotate the mandible in this way, while the least stable advancements are those that rotate it in the opposite direction, lengthening the ramus and rotating the chin up. . www.indiandentalacademy.com
  83. 83. • The least stable orthognathic surgical procedure, widening the maxilla, stretches the heavy, inelastic palatal mucosa www.indiandentalacademy.com
  84. 84. PRINCIPLE 2 • . Neuromuscular adaptation is essential for stability. Fortunately, most orthognathic procedures lead to good neuromuscular adaptation. When the maxilla is moved up, the postural position of the mandible alters in concert with the new maxillary position, and occlusal forces tend to increase rather than decrease. www.indiandentalacademy.com
  85. 85. • This controls any tendency for the maxilla to • immediately relapse downward, and contributes to the excellent stability of this surgical movement. Repositioning of the tongue to maintain airway dimensions, (i.e., a change in tongue posture) occurs as an adaptation to changes produced by mandibular osteotomy. www.indiandentalacademy.com
  86. 86. • In contrast, neuromuscular adaptation does not • • occur when the pterygomandibular sling is stretched during mandibular osteotomy, as when the mandible is rotated to close an open bite as it is advanced or set back That’s why movement of the mandible that stretches the elevator muscles must be avoided. Syndromic patients who have neuromuscular problems (cerebral palsy, for example) are not good candidates for any type of orthognathic surgery because they cannot adapt to the changes. www.indiandentalacademy.com
  87. 87. PRINCIPLE 3 •Neuromuscular adaptation affects muscular length, not muscular orientation. •If the orientation of a muscle group such as the mandibular elevators is changed, adaptation cannot be expected. www.indiandentalacademy.com
  88. 88. • This concept is best illustrated by the effect of changing the inclination of the mandibular ramus when the mandible is set back or advanced. • Successful mandibular advancement requires keeping the ramus in an upright position rather than letting it incline forward as the mandibular body is brought forward. www.indiandentalacademy.com
  89. 89. • The same is true, in reverse, when the mandible is set back: major cause of instability appears to be the tendency at surgery to push the ramus posteriorly when the chin is moved back. www.indiandentalacademy.com
  90. 90. • Although most patients are quite stable long• • term and average changes are small. However long term follow up studies shows that some patients do have a surprising amount of change in the position of skeletal landmarks beyond the first postsurgical year. Long-term condylar resorption is of particular concern. As one would expect, long-term condylar changes are not observed in patients who had maxillary surgery only www.indiandentalacademy.com
  91. 91. • At 5-year recall, bony changes associated with • shortening of the condylar processes (which may not be associated with surgical relapse), were observed in approximately 5% of the relatively large group of patients who underwent mandibular advancement at UNC (University of North Carolina) with or without simultaneous maxillary surgery. Surprisingly, although surgical correction of Class III problems is less stable than Class II correction in the short-term postsurgically, it appears to be more stable long-term. www.indiandentalacademy.com
  92. 92. • It has not been determined why a few patients are susceptible to long-term changes. It is important to continue to follow well-defined groups of patients who received orthognathic surgery, to improve the quality of the data available, and to resolve questions of long-term stability. www.indiandentalacademy.com
  93. 93. Soft tissue after surgery • The success of orthognathic surgery relies on predictable skeletal and soft-tissue movements and stable long-term results. • Although edema and muscular readaptation are expected to resolve by 6 to 12 months, soft tissue changes of the lower lip and chin continue to occur up to 3 years postsurgically after mandibular advancement. www.indiandentalacademy.com
  94. 94. • There are three distinct possibilities for long-term • • • soft tissue changes in surgically treated patients: (1)resolution of edema or other soft tissue change related to the surgery itself; (2) postsurgical growth and remodeling of hard tissue landmarks, which would be reflected in changes in the overlying soft tissue; and (3) soft tissue changes as a result of maturation and aging. www.indiandentalacademy.com
  95. 95. Soft tissue changes due to aging • soft tissue changes are obvious. Significant typical changes include thinning of the lips and downward movement of the lips relative to the teeth so that maxillary incisor display decreases and mandibular incisor display increases, an apparent lengthening of the lower face, and flattening of the upper lip on profile view. www.indiandentalacademy.com
  96. 96. • In males the profile straightens and the lips • become more retrusive, the nose increases in size in all dimensions, and soft tissue thickness at pogonion increases. In contrast, in females the profile does not straighten and the lips do not become more retrusive, the nose does not increase in size as much as in males, and the soft tissue thickness at pogonion decreases. www.indiandentalacademy.com
  97. 97. • From the stability studies at UNC over the past • decade, it appears that the pattern of change with Class III treatment is different from that seen with surgical Class II treatment. Although the skeletal Class II patients have very little net change during the first postsurgical year, a surprisingly larger number show skeletal and associated soft tissue changes beyond 1year. www.indiandentalacademy.com
  98. 98. Long term soft tissue changes due to orthognathic surgery www.indiandentalacademy.com
  99. 99. L’Tanya J. Bailey; Amy Joslin Dover; William R. Proffit AO 2007 • The purpose of the current investigation was to compare the long-term soft tissue changes in Class III patients treated with orthodontics alone with those who had surgery to correct the problem, either by advancement of the maxilla, mandibular setback, or a two-jaw procedure. www.indiandentalacademy.com
  100. 100. • When soft-tissue changes in Class III patients • are compared with the typical changes in untreated adults, it was interesting that the younger orthodontics only group showed the typical aging changes, whereas in several ways the surgery patients did not. One of the primary differences between the orthodontics only and surgical treatment groups was the tendency for an increase in prominence of the soft tissue chin for the surgery groups , especially those with two-jaw surgery patients, which occurred in females as well as males. www.indiandentalacademy.com
  101. 101. • Beyond 1 year postsurgery, there also was less flattening of the lips in the surgery patients than would have been expected without treatment; less downward sag of the soft tissue profile; and, in those who had mandibular surgery, less increase in soft tissue face height. www.indiandentalacademy.com
  102. 102. • The Class III patients are less stable during the first year but show fewer changes in hard tissue measurements beyond that point. • This appears to hold true for the soft tissue measurements as well, as fewer than 20% of patients in this study experienced significant soft tissue change from 1 year to 5 years or more. www.indiandentalacademy.com
  103. 103. • In general, skeletal Class III patients who were treated with orthognathic surgery experienced minimal change in soft tissues between 1 and 5 years or more postsurgery. • No mean changes were greater than 2 mm or 2, and fewer than 20% of variables showed statistically significant mean changes. www.indiandentalacademy.com
  104. 104. • The orthodontics-only patients showed the facial soft tissue changes that are typical of aging in untreated individuals, but the surgery patients differed in that both genders tended to have an increase in soft tissue thickness at the chin and did not show as much thinning of the lips or downward sag of the of tissue profile as would be expected without treatment. www.indiandentalacademy.com
  105. 105. CONCLUSION • It can be concluded that successful results can be attained with proper diagnosis and treatment planning in cooperative patients with favorable growth patterns. • Regardless of the person's growth potential, long-term stability ultimately depends on the orthodontist's ability to first match the proper treatment to the proper patient and secondly, ensure high quality treatment results www.indiandentalacademy.com
  106. 106. REFERENCES:- • 1. Ghafari], Shofer FS, Jacobsson-Hunt U, et al:-- Headgear versus function regulator in the early treatment of ClassII, Division I malocclusion: a randomized clinical trial. Am] Orthod Dentofacial Orthop 1998 113:51-61, • 2. Tulloch FC, Proffit WR; Phillips SC: Outcomes in a 2-phase randomized clinical trial of early class II treatment. Am] Orthod Dentofacial Orthop 2004 ;125:657-667, www.indiandentalacademy.com
  107. 107. • 3. Bowman SJ:-- One-stage versus two-stage treatment: are two really necessary? Am J Orthod Dentofacial Orthop 1998 ;113:111-116, 4. Ruf S, Pancherz H: --When is the ideal period for Herbst therapy-early or late? Semin Orthod 2003; 9:47-56, www.indiandentalacademy.com
  108. 108. 5. Dermaut LR, Aclbers CM:---Orthopedics in orthodontics: 6. 7. 8. fiction or reality. A review of the literature-part II. Am J Orthod Dentofacial Orthop 1996;110:667-671, Pancherz H. Fackel U: ---The skeletofacial growth pattern pre- and post-craniofacial orthopaedics. A long-term study of Class II malocclusions treated with the Herbst appliance. Eu J Orthod 1990 ;12:209-218, Sadowsky C, Theisen TA, Sakols EI.---- Orthodontic treatment and temporomandibular joint sounds: a longitudinal study. AM J ORTHOD DENTOFAC ORTHOP 1991;99:441-7. Sadowsky C, BeGole EA.--- Long-term status of temporomandibular joint function and functional occlusion after orthodontic treatment. AM J ORTHOD 1980;78:201-12. www.indiandentalacademy.com
  109. 109. 9. Sugawara J, Asano T, Endo N, Mitani H.-- Long-term effects of chincap therapy on skeletal profile in mandibular prognathism. Am J Orthod Dentofac Orthop 1990;98:127-33. 10. Sang J. Sung, and Hyoung S. Baik---, Assessment of skeletal and dental changes by maxillary protraction--Am J Orthod Dentofacial Orthop 1998;114:492-502 11.  Dibbets JMH, Weele LT.-- Extraction, orthodontic treatment, and craniomandibular dysfunction. AM J ORTHOD DENTOFAC ORTHOP 1991;99:210-9. www.indiandentalacademy.com
  110. 110. 12. Sadowsky C, Polson AM. Temporomandibular disorders and functional occlusion after orthodontic treatment: results of two long term studies. AM J ORTHOD DENTOFAC ORTHOP 1984;86:386-90. 13. Dibbets JM, van der Weele LT.---- Orthodontic treatment in relation to symptoms attributed to dysfunction of the temporomandibular joint. AM J ORTHOD DENTOFAC ORTHOP 1987;91:193-9. 14. Gianelly AA, Cozzani M, Boffa J. ---Condylar position and maxillary first premolar extraction. AM J ORTHOD DENTOFAC ORTHOP 1991;99:473-6. www.indiandentalacademy.com
  111. 111. 15. Egermark-Eriksson I, Carlsson GE, Ingervall B.--- Prevalence of mandibular dysfunction and orofacial Para function in 7, 11, and 15 year old Swedish children. Eur J Orthod 1981;3:163-72. 16. L’Tanya J. Bailey; Amy Joslin Dover; William R. Proffit --Long-term Soft Tissue Changes after Orthodontic and Surgical Corrections of Skeletal Class III Malocclusions-Angle Orthodontist, Vol 77, No 3, 2007 page 389-396 www.indiandentalacademy.com
  112. 112. 17. Van Sickels JE, Richardson DA. Stability of orthognathic surgery: a review of rigid fixation. Br J Oral Maxillofac Surg1996;34:279-85. 18. Heon Jae Choa ---Long-Term Stability of Surgical Mandibular Setback-- Angle Orthodontist, Vol 77, No 5, 2007;851-856 19. Bailey LJ, Cevidanes LH, Proffit WR. Stability and predictability of orthognathic surgery. Am J Orthod Dentofacial Orthop. 2004;126(3):273– 277. www.indiandentalacademy.com
  113. 113. Thank you www.indiandentalacademy.com Leader in continuing dental education www.indiandentalacademy.com

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