Extractions vs non extraction debate
- 1. EXTRACTION vs NON EXTRACTION IN ORTHODONTICS 5/09/2017 Dr.Arpana shekhawat 2ND M.D.S Department of Orthodontics&Dentofacial Orthopaedics,GDC,jaipur.
- 2. CONTENTS • INTRODUCTION • EVALUATION OF DIAGNOSTIC ELEMENTS • CHOICE OF INDIVIDUAL TEETH
- 3. INTRODUCTION • Generally there are three reasons to extract the teeth; 1.To provide space for the alignment of crowded teeth. 2.For the retraction of protruded teeth. 3.For camouflaging the skeletal class II and class III malocclusions.
- 4. 4 The Great Extraction controversy • Extraction of deciduous teeth- ancient times • Celsus, Fauchard- recommended • Controversy- permanent teeth extraction • Hunter- 17th century- opposed- inhibited growth • Early 1800s- extraction of 1st premolars- Class II div 1 malocclusion • Delabarre- 1818- It is much easier to extract teeth than to determine if it is absolutely necessary
- 5. 5 • Kingsley- gave up • Davenport- 1887- loss of important organs • Case- 1893- reintroduced- though arches could be expanded- neither esthetics nor stability satisfactory in the long run Although done only in severe cases- 6% • Angle- 6th and 7th publications- non extraction
- 6. b. Wolff’s Law of bone: Bone trabeculae were arranged in response to stress lines on the bone.
- 7. This led Angle to 2 key concepts: I. Skeletal growth could be readily influenced by external pressure. II.If teeth were placed in proper occlusion, forces transmitted to teeth would cause bone to grow around them and so stabilizing them in a new position even if great deal of arch expansion had occurred.
- 8. 8 • Case- 1911- article “the question of extraction in orthodontia” (Dental cosmos 1912) • Martin Dewey- challenged Case • Angle followers- won the day- 30 years- nonextraction • John Mershon, Joseph Johnson, George Crozat- nonextraction
- 9. These concepts did not go unchallenged. Calvin Case argued that although arches could always be expanded, neither esthetics nor the stability would be satisfactory in long term in many patients. This controversy culminated in debate between Angle’s student Dewey and Case. Angle’s followers won the day.
- 10. 2. THE RE-INTRODUCTION OF EXTRACTION IN THE MID 20TH CENTURY. Relapse after non-extraction treatment was frequently observed by 1930. Charles Tweed & Raymond Begg, both adapted ‘EXTRACTION WHEN NECESSARY’ approach and treated their patient with this philosophy. They found that occlusion was stable and esthetics was improved.
- 11. 11 Re-introduction of extraction in mid-century • 1930- relapse frequently observed • First to analyze relapse scientifically – Alex Lundstrom - Stockholm, Sweden • Apical base is deficient- crowded teeth corrected by orthodontic means- relapse
- 12. 12 • By the early 1960s- more than 50% American patients- extraction treatment (not always first premolars) • Concept- orthodontic treatment could not affect facial growth • Hereditary cause • Lack of proximal wear
- 13. 13 Recent trends toward non-extraction • Extraction of all 4s- decreased
- 14. 14
- 15. 15 • Reason for decrease in extraction cases • Collapse of expanded arches- stable occlusion- no guarantee Extraction – may not be stable- no reason to sacrifice teeth
- 16. 16 • General public – fuller lips • 1980s- extractions- TMD
- 17. 17 What is a borderline case? • Buchin- Borderline case- when extraction of teeth is required to reach stable and functional occlusion , but patient has good facial esthetics that could be disturbed by extractions characteristics: • • Absence of dental or craniofacial anomalies. • • Permanent dentition. • • Healthy periodontium. • • Normal anteroposterior relationship between maxilla and mandible (skeletal Class I).
- 18. 18 Criteria for extraction • Arch length discrepancy • Facial esthetics: - Will flattening middle and lower third of face improve esthetics? - Will soft tissue drape be representative of the skeletal scaffold, how much will chin and nose grow?
- 19. 19 - Competency of lips - Sex, ethinicity • Skeletal disharmony- • Patient cooperation
- 22. EVALUATION OF DIAGNOSTIC ELEMENTS FOR EXTRACTION CLINICAL PARAMETERS I. FACIAL APPEARANCE II. SOFT TISSUE PROFILE III. MIDLINE IV. GROWTH MODEL ANALYSIS I. CAREY’S MODEL ANALYSIS II. CURVE OF SPEE III. BOLTON DISCREPANCY IV. IRREGULARITY INDEX CEPHALOMETRIC VARIABLES VERTICAL FACIAL PROPORTIONS. I. FMA II. SN-MP III. JARABAK RATIO LOWER INCISOR POSITION. I. IMPA II. FMIA III. LOWER INCISOR TO A-Pog DISTANCE
- 23. CLINICAL PARAMETERS I. FACIAL APPEARANCE: • Facial appearance -consideration -planning orthodontic treatment. • Genetic makeup, • Environmental influences, • and cultural background. • How extractions vs arch expansion affects facial appearance is a major concern for orthodontists.
- 24. II. SOFT TISSUE PROFILE. • How extraction vs non-extraction therapy affects the profile also is a concern. • Extraction therapy is sometimes believed to be detrimental to the profile.
- 25. Facial appearance of the patient following treatment after 1Yrs and 9 months P R E - T R E A T M E N T P O S T - T R E A T M E N T 25
- 26. • This is important because, if a patient has proclined incisors or proclined incisors with crowding. • it would be virtually impossible to improve the anteroposterior position of the teeth and the patient’s profile without extractions.
- 27. III. MIDLINE: • According to Strang , the harmonic positioning of the midlines relative to each other and to the face is what characterizes normal occlusion. • Any variation in this combination is indicative of improper relationship between the teeth or dental arches.
- 28. • This requires a careful diagnosis because properly assessing the causes behind midline shifts allows professionals to use unique mechanics and asymmetric extractions. • Patients presenting with severe dental midline deviation relative to the face require tooth extractions.
- 29. IV. GROWTH STATUS. • In malocclusions with skeletal discrepancies it is crucial—for the diagnosis and prognosis of the case—to check whether the patient is still undergoing significant facial growth. • If a malocclusion can be corrected with growth response (growth redirection), clinicians can handle the case without extractions.
- 30. MODEL ANALYSIS I. CAREY’S ANALYSIS: • First determine the degree of discrepancy between bone and tooth structure. • If the discrepancy is 2.5 mm. or less, we do not extract. • If it is 2.5 to 5.0 mm., we extract the second premolars, whenever possible, to obtain better esthetics. • If it is more than 5 mm., we extract the first premolars.
- 31. • If the discrepancy is extreme (5 mm. or more), in the lower arch and mild in the upper, we extract the lower first and upper second premolars, and vice versa. • When the discrepancy is confined to the maxillary arch, two upper first or second premolars are removed, the choice depending upon the degree of the deficiency.
- 32. II. CURVE OF SPEE: • Levelling the curve increases incisor protrusion. • Recent studies conclude the real effect to be closer to 1:3; for every 3 mm of curve levelled, arch circumference increases 1 mm. • The deeper the Curve of Spee, the greater the need for extraction.
- 33. III. BOLTON DISCREPANCY. • An interarch tooth-size discrepancy may provide incentive to extract in order to establish a proper occlusion. This diagnostic variable has been popularized as the Bolton discrepancy. • Clinicians have utilized interproximal reduction to resolve interarch tooth size discrepancies.
- 34. • Bolton noted a 4 mm limit to anterior reduction. Thus, extraction may be necessary to resolve a discrepancy greater than this.
- 35. CEPHALOMETRIC VARIABLES VERTICAL FACIAL PROPORTIONS: I. SN-MANDIBULAR PLANE ANGLE(SN-MP) • Schudy utilized the angle formed at the intersection of the sella-nasion and mandibular planes (SN-MP)to aid in his assessments, and found the value of 33 degrees to be average for balanced vertical facial types, with a range of 31 to 34 degrees.
- 36. II. FRANKFORT MANDIBULAR PLANE ANGLE(FMA). • The FMA provides an additional vertical appraisal to the SN-MP measurement. • A normal value for the FMA is in the range of 20 to 30 degrees. • Values above these normal ranges are associated with skeletal open bite, whereas values below are typically associated with skeletal deep bite.
- 37. III. JARABACK RATIO: • The PFH (distance between sella and gonion) is divided by the AFH (distance between nasion and menton). • The normal value is 61-69%. • Less than 61% suggests a skeletal open bite; greater than 69% indicates a skeletal deep bite.
- 38. LOWER INCISOR POSITION: I. INCISOR MANDIBULAR PLANE ANGLE(IMPA): • Charles Tweed used the orientation of the mandibular incisor to aid in treatment planning to create facial balance and harmony. • He noted a need for “upright” and “vertical” lower incisors. • Margolis proposed the incisor mandibular plane angle (IMPA) to quantitatively define these two qualities.
- 39. • He proposed IMPA to be 90+/-3 degrees in normal, balanced faces. • According to Tweed, this value can range between 85 and 95 degrees, and vary according to ethnicity. • Values above this range are indicative of extraction to improve functional and esthetic imbalance.
- 40. II. FRANKFORT MANDIBULAR INCISOR ANGLE(FMIA): • The norm for the angle formed by the intersection of the Frankfort plane and the long axis of the lower incisor is 60-70°. • A value less than 60° indicates proclination of the lower incisors, whereas a value greater than 70° suggests that the lower incisors are retroclined.
- 41. III. LOWER INCISOR TO A-Pog DISTANCE: • McNamara found the proper position of the mandibular incisor to be 1 to 3 millimeters anterior to the line from point A to Pogonion (A-Pog) in a well- balanced face, regardless of age.
- 42. Extraction Decision- Making Wigglogram- Rody, Ajo- 2002
- 44. CHOICE OF INDIVIDUAL TEETH 1. UPPER INCISOR EXTRACTION: INDICATIONS: • Unfavorably impacted incisor. • Buccally or lingually blocked out lateral incisor with good contact between central incisor and canine. • Congenitally missing one of lateral incisor, opposite incisor may require extraction to maintain arch symmetry.
- 45. • Grossly carious incisor. • Malformed incisor that can not be restored. • Trauma or irreparable damage. • An incisor with dilacerated root.
- 46. 2. LOWER INCISOR EXTRACTION: • In 1905, Jackson described a case in which two lower incisors were extracted at different times to relieve mandibular crowding. • Hahn(1942) advocated the removal of a mandibular incisor to close the space and thus reduce the anterior dentition.
- 47. INDICATIONS: (Permanent dentition,Minimal growth potential, Class I molar relationship, Harmonious soft-tissue profile,Minimal-to- moderate overbite, Little or no crowding in the maxillary arch) • Existing Bolton discrepancy • Tooth-size-arch-length discrepancy of more than 5mm in the anterior region
- 48. WHICH INCISOR TO BE REMOVED? • Periodontal conditions • gingival recession • any restorations,including endodontic treatment. • Extraction of a lateral incisor is generally preferred because it is less visible from the front.
- 49. 3. CANINE EXTRACTION INDICATIONS: •Extremely unfavourable cuspid position. •Tooth position unfavourable for orthodontic movement. •Ankylosed tooth. •Internal or external root resorption. •Severe dilaceration.
- 50. Transmigrated canine in mandibular arch
- 51. 4. PREMOLAR EXTRACTION: • In 1949, Nance stated that the term extraction had, at that time, become synonymous with the removal of all four first premolars. Augmenting anchorage, maximum lip retraction, better contact between the canines and second premolars • first premolars are nearer to anterior crowding are some of the reasons behind favouring their extraction.
- 52. 1ST PREMOLAR EXTRACTION 2ND PREMOLAR EXTRACITON ANCHORAGE NOT SIGNIFICANT NOT SIGNIFICANT LIP RETRACTION NOT SIGNIFICANT NOT SIGNIFICANT FACIAL VERTICAL DIMMENSION NOT SIGNIFICANT NOT SIGNIFICANT TOOTH SIZE DISCREPANCY MORE EVIDENT LESS EVIDENT CLINICAL CONSIDERATIONS NOT FAVOURABLE FAVOURABLE MOTHER NATURE’S RULE DOESN’T ALLOW ALLOW
- 53. Second premolars • The indications for extraction of second premolars include the following: 1. congenital absence of the second premolars and crowding of the arch; 2. hypoplasia of the second premolars and crowding of the arch; 3. severe displacement of the second premolar; 4. mild to moderate crowding (2–4 mm per quadrant); 5. where space closure by forward movement of the molars rather than retraction of the labial segments is indicated.
- 54. Second premolars • Extraction of the second premolars is preferable to extraction of the first premolars in cases with mild to moderate crowding as their extraction alters the anchorage balance, favouring space closure by forward movement of the molars.
- 55. 5. 1ST MOLAR EXTRACTION: • “First permanent molar extractions doubling the treatment time and halving the prognosis” was the phrase coined by Mills. • Daugaard-Jensen suggested that first molar cases are no more time consuming than 4 premolar cases. • Williams and Hosila highlighted the fact that first molar extraction cases are likely to have less effect on the profile than premolar extraction cases.
- 56. INDICATIONS:( Sandler et al 2000) • Extensively carious first molars. • Hypoplastic first molars. • Heavily filled first molars where premolars are perfectly healthy. • Apical pathoses or root canal treated first molars. • Crowding at the distal part of the arches and wisdom teeth reasonably positioned. • High maxillary/mandibular planes angle (Anterior open bite cases).
- 57. • TIMING OF EXTRACTIONS: If the upper second molars are unerupted at the time of extraction of the upper first molars, they will almost completely replace them, thus contributing little space for correction of the malocclusion. If there is a space requirement in the upper arch therefore, extraction of the first molars must be delayed until the second molars have erupted sufficiently to allow a palatal arch with Nance button or headgear to be placed.
- 58. 6. 2ND MOLAR EXTRACTION: INDICATIONS(Lehmann 1979) • The second molars are severely carious, ectopically erupted, or severely rotated. • Skeletal Class I malocclusions with arch length discrepancy in the distal part of the arch or with mild anterior crowding and • In Class II "skeletal" cases with only mild crowding of the mandibular arch.
- 59. ADVANTAGES: • Disimpaction of third molars • Faster eruption of third molars • Prevention of "dished-in" appearance of the face at the end of facial growth • Prevention of "late" incisor imbrication • Facilitation of first molar distal movement
- 60. TIMINGS OF EXTRACTION: (Kokich 1983) • The third molar crowns should be completely formed but extractions should be performed before the roots begin to develop; • The axial inclination of the third molar buds should not be greater than 30 ° relative to the occlusal plane; • The mandibular third molar should be in close proximity to the second molar roots to ensure adequate mesial drift of the third molar as it erupts.
- 61. 61 Alternatives to extraction Expansion vs Extraction Esthetics - Lip fullness
- 62. 62 • At what point have incisors moved too far forward? • >4 mm lip separation at rest- incompetent lips
- 63. 63 - Size of nose and chin individual with a large nose or chin, it is better to have fuller lips, provided it does not diminish the mentolabial sulcus too much. • For best aesthetics, the lower lip should be at least as prominent as the chin. Retroclining the lower incisors too much may cause the lower lip to fall back leading to a concave profile which is unaesthetic. •
- 64. 64
- 65. 65 • Stability considerations - Amount of arch expansion - Lower arch more constrained than upper
- 66. 66
- 67. 67 Expansion by opening the midpalatal suture- lower arch will follow upper But if limiting factor is cheek pressure- no significant difference Excessive expansion- fenestration, dehiscence of molar, premolar roots- 50% skeletal, 50% dental movement 12mm expansion- 3mm per side dental
- 68. 68 Contemporary extraction guidelines Class I crowding cases • < 4mm discrepancy- non extraction • 5-9 mm- borderline cases • > 10 mm discrepancy- extraction
- 69. 69 • Final set of guidelines: - If extraction spaces can be closed without retracting too much, expansion carried out without proclining too much.. Esthetics not affected a great deal For masticatory function and oral health, it makes no difference either way
- 70. 70 Reproximation • “Stripping is defined as the act of clinically removing part of the dental enamel from an interproximal contact area.” (AO 2007). • Sheridan and Fillion 1985…..slenderization techchnique currently in use
- 71. 71 INDICATIONS: • Mild to moderate crowding in anterior areas….class I • Good oral hygiene • Mild tooth material excess …. Bolton’s analysis • Post treatment relapse • Tooth shape deviations (Peck & peck index)
- 72. 72 CONTRAINDICATIONS • SMALL TEETH • RESTORED TEETH WITH NORMAL SHAPE • ENAMEL HYPOPLASIA • POOR ORAL HYGIENE • HIGH CARIES & PLAQUE INDEX • RECTANGULAR SHAPED TEETH • VERY YOUNG PATIENTS
- 73. 73 Approximately 50% of the interproximal enamel can be safely removed ( Boese -AO 1980) Fillión : Mesial surface of the first right molar to the same surface of the left molar 10.2 mm of space in the maxilla 8.6 mm in the mandible.
- 74. 74 AIR ROTOR STRIPPING Dr John J. Sheridan in JAN 1985.
- 75. 75 “Air rotor stripping is a technique to remove controlled amounts of enamel in the posterior segments to gain arch length for retracting and aligning anterior teeth”(AJO FEB’94) -Primarily in the buccal quadrants (upto 8mm space gain) - Treatment philosopy …… Difficulties in adult extraction Instability of expansion
- 76. 76 Molar Distalization • Patient with Class II molar- no obvious skeletal deficiency • Acceptable facial esthetics • Upper incisors – normal, retroclined • Canines bucally blocked out • Minimal arch length discrepancy • Low MPA
- 77. 77 Negatives of extractions • Tendency towards recrowding in lower anterior region • Deepening of anterior overbite • Incomplete contact points, improper marginal ridges, plunger cusps- perio problems • Streamlining of face- large nose, big chin point, retrusive dentition
- 78. 78 Comparison of the changes in facial profile after orthodontic treatment with and without extractions, in "borderline" Class I crowding female patients - Arch length discrepancy - 3 to 7mm - No severe incisor and lip protrusion and no severe vertical discrepancy
- 79. 79 - Soft tissue differences between two groups - end of treatment - more protruded lower lip in non- extraction patients - Significant hard tissue difference between two groups - only limited to- more labial inclination of the incisors in non-extraction patients - Borderline cases can be treated with satisfactory occlusions and esthetics either way. This is true if expansion is managed so as not to produce too much protrusion, or space closure after extraction is controlled so as not to produce too much incisor retraction
- 80. 80 • Are we more concerned with the face rather than the patient? • Calvin Case: No matter how irregular the teeth, however bunched, malaligned or malposed, they can always be placed in their respective places in the arches and in normal occlusion. Therefore, so far as the relations of the teeth to each other are concerned, no dental malposition should be taken as a basis for extraction. The only excuse, then, for the extraction of savable teeth must be that it is inexpedient or impossible to correct their positions in that way without producing facial protrusion." - Stability
- 81. 81 • Facial balance with the major objective- clinical experience • It is always a problem when someone asks a question and uses a term that has meaning to him but perhaps a different meaning to the man answering the question. We refer to clinical experience and diagnostic criteria. To me, clinical experience is only a measure of the operator's ability. It varies with each of us. Our clinical experience is "what we can do".
- 82. 82 • Diagnostic criteria are generally specifics that we take from someone else such as a Tweed triangle or a Downs analysis. In our working practices we have to give preference to the clinical experience we have attained over the numbers that someone may have given us. So, if we do have a conflict, I think it is perfectly legitimate to use clinical experience or therapeutic treatment in preference to some arbitrary scale of which we are not completely sure. It may change tomorrow.
- 83. 83 Summary- Century Orthodontics • All or nothing nature of premolar extractions- different orthodontists – conflicting views • Each doctor has different gray between extraction and nonextraction
- 84. 84 • Borderline cases- no right answers • Try to avoid extractions as much as possible • Esthetics, stability • Conflict between esthetics, stability- esthetics • Not that flat profiles, crowding- nonextractions
- 85. 85 • Contrary to nonextraction believers- no TMDs • Well treated extractions- no adverse effect on facial profiles • Visualize patients with flat profiles with premolar extractions • Truth- tight facial structures – crowding- extractions- not vice versa
- 86. 86 • Most dished in – nonextraction • dark buccal corridors and a narrow smile are not “caused” by premolar extractions.
- 87. 87 • Good selling point for premolar extractions- moderate crowding, well formed and positioned 3rd molars • no guarantee can be made that the thirds will always come in with enough room
- 88. 88 • Great deal of confusion about early expansion treatment • Important difference between expanding a constricted upper arch to match a normal lower arch • significantly expanding both arches in a patient whose arches may be narrow, but are in a normal transverse occlusal relationship to each other
- 89. 89 • Possible to upright lingually verted lower posterior arches (which may have collapsed in, to compensate for a narrow maxillary arch), it is not possible to expand the mandibular basal bone - is no suture to distract as in the maxilla • One of the most established - stability of the lower inter-canine width • Expansion beyond the original width - almost a guarantee of collapse and recrowding
- 90. 90 In an attempt to avoid first premolar extractions, various alternatives can be considered: - Expanding the arch, especially in flat-faced individual- preferable to extractions - unstable correction - retention will be needed - Patients with good posterior occlusion, good upper arch with relatively small upper incisors, moderately severe lower crowding, minimal overbite - extraction of lower incisor Should be evaluated very carefully- untreatable problem with excessive overjet/overbite
- 91. 91 • Interproximal enamel reduction (IPR) can provide a moderate amount of room but should be reserved for older patients. Excessive IPR as an initial treatment complicates the orthodontist’s ability to correct minor relapses in the future.
- 92. 92 • Consider extraction of second premolars rather than first premolars. • Theoretically- reduces the amount of anterior retraction when only some space is needed for crowding and facial profile is acceptable • Works best when second premolars resemble the first, but large, molar-like second premolars may provide too much room and small, canine-like first premolars may not work against first molars
- 93. 93 • No right answers in borderline cases • Both T/t performed by competent orthodontists- satisfactory results- neither perfect
- 94. 94 • Borderline cases- greatest responsibility • Sensitive • if the wrong decision is made or if the mechanics are not carried out correctly, one really stands to do a great disservice to the patient.
- 95. 95 Extractions are just a tool, not good or bad in themselves. Used right, they improve the quality of treatment, used wrong they may create a poor result.
- 96. 96 THANK YOU
- 97. MCQ: 1.Extraction of teeth in conjunction to orthodontic treatment is necessary in order to (A)To relieve crowding in the arches especially when jaws are not large enough to accommodate all the teeth (B)To achieve proper sagittal inter-arch relationship (C)Just as a procedure of orthodontics (D)Both A and B 2. The decision of extraction is based on the following factors (A)Patient’s age (B)Sex of the patient (C) The amount of space needed for tooth alignment (D) All of the above 97
- 98. 3.The decision to opt for extraction should only be made (A)After careful clinical evaluation (B)After model analysis done (C)After cephalometric tracing done (D)All of the above 4. Injudicious extraction of teeth can cause (A)Arch collapse (B)Deep overbite (C) Spacing and tissue damage (D) All of the above 98
- 99. 5.Who was the major proponent of “ Non Extraction Philosophy” (A)Edward H Angle (B)Calvin Case (C)John Hunter (D)All of the above 6. Who introduced the concept of extraction as a part of orthodontic treatment. (A)Calvin Case (B)Charles Tweed (C)Angle (D)Jhon Hunter 99
- 100. 7.Most commonly extracted teeth for orthodontic purpose are (A)Maxillary first molars (B)Maxillary and mandibular premolars (C)Mandibular incisors (D)Maxillary incisors 8. The tooth most rarely extracted as a part of orthodontic treatment (A)Maxillary central incisors (B)Maxillary third molars (C)Mandibular third molar (D)Maxillary and mandibular premolars 100
- 101. 9. What are the different extraction procedures? (A)Balanced extraction (B)Compensatory extraction (C)Enforced extraction (D)All of the above 10. Compensatory extraction refers to (A)Extraction of tooth in the opposite jaw to the same teeth group (B)The extraction of a tooth in the same jaw to the same teeth group (C)The extraction of a tooth in the cotralateral side to the same teeth group (D)None of the above 101
- 102. REFERENCES 1. Graber TM:Principles and Practicce Orthodontics,WB Saunders,1988 2.Profitt.Contemporary Orthodontics,Elsevier India.3rd ed.,2000. 102
- 103. 103