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Surgery Marked facial convexity
Severe lip protrusion Severe crowding Extremely proclined incisors D.T. Schwab. Extraction Effects On The Dental Profile In Borderline Cases. (Angle Orthod 1963; 33: 120-122) W. R. Proffit. Contemporary orthodontics. Fourth edition, 2007 Edward Angle and the Non-Extraction Philosophy “there should be a full complement of teeth and each tooth shall be made to occupy its normal position…” Expansion of the arches
Rubber bands as needed to bring the teeth into occlusion Extraction was NOT necessary for stability or esthetics. Stability Proper function of the dentition is the key to maintaining teeth in their correct position. Esthetics Ideal facial esthetics would result when the teeth were placed in ideal occlusion. Bone growth Proper occlusion Stabilizing teeth in their new position The Re-introduction of Extraction in the mid 20th Century By the 1930’s, relapse after non-extraction treatment was frequently observed.
Charles Tweed, decided to re-treat with extraction a number of his patients who had experienced relapse. Reemergence of non-extraction expansion doctrine D. Damon. Three keys to non-extraction therapy. (Ortho Tribune 2006; Vol.1, No.3: 1: 13-14) An extractionist or a non-extractionist?!! Key factors to consider: Periodontally sound end result.
Vertical and horizontal skeletal pattern of the patient.
Protrusion or retrusion of the incisors. R.P. McLaughlin, J.C. Bennett.The extraction-nonextraction dilemma as it relates to TMD. (Angle Orthod 1995; 3: 175-186) Facial profile.
Thickness and shape of the lips.
Size and shape of the nose.
Size and shape of the chin. S. J. Burrow. The Impact of Extractions on Facial and Smile Aesthetics. (Semin Orthod 2012;18:202-209) Arch length discrepancy.
Curve of Spee.
Patient’s age and compliance. H.J. Lim, K.T. Ko, H.S. Hwang. Esthetic impact of premolar extraction and nonextraction treatments on Korean borderline patients. (Am J Orthod Dentofacial Orthop 2008;133:524-31) Dimensions of the dentition There are anterior, posterior, lateral, and vertical dimensions of the dentition and its supporting structures. J.L. Vaden and H.E. Kiser. Straight talk about extraction and A differential diagnostic decision. (Am J Orthod Dentofac Orthop 1996; 109:445-52) The anterior dimension Uprighting proclined mandibular anterior teeth Facial balance Stability High FMA Low FMA Extraction Non-extraction Treatment that involves the attempted distalization or holding-back of the molars, aimed at creating anterior space and preventing premolar extractions, tends to create posterior space deficiencies. S Kandasamy, MG Woods. Is orthodontic treatment without premolar extractions always non-extraction treatment? (Australian Dental Journal 2005;50:146-151) The posterior Dimension Premolar extractions have generally resulted in greater space in the third molar region, and a general improvement in the angulations of the lower third molars in relation to the occlusal plane. S Kandasamy, MG Woods. Is orthodontic treatment without premolar extractions always non-extraction treatment? (Australian Dental Journal 2005;50:146-151) Third molar angulations should be included in the treatment planning of borderline extraction cases. The prognosis for the third molars should be assessed early, with the third molars being removed if no premolar extractions were to be part of the planned treatment. Ricketts RM. A principle of arcial growth of the mandible. (Angle Orthod 1972;42:368-386) J. Suruchi and V. Ashima. Influence of First Premolar Extraction on Mandibular Third Molar Angulation. (Angle Orthod. 2009;79: 1143–1148) Distalization Mesial Drift of permanent molar The vertical dimension "wedging open" effect Longer face L.L. Merrifield, J.J. Cross. Directional force. (Am J Orthod 1970;57:435-64) 1 mm 1.3 mm Point B drops down and back.
Poor facial esthetics The lateral dimension Transverse expansion across the canines is almost never maintained, especially in the lower arch. Expansion across the Premolars and molars is much more likely to be maintained >3 mm Fenestration Esthetic considerations Dimensions of the dentition R. H. W. Strang. The Fallacy of Denture Expansion As a Treatment Procedure. (Angle Orthod 1949; 19: 12-22) Lip prominence Merrifield LL. The profile line as an aid in critically evaluating facial esthetics. (Am J Orthod 1966; 52: 804-822) The lips will move two-thirds of the distance that the incisors are retracted, i.e., 3 mm of incisor retraction will reduce lip protrusion by 2 mm, but only until lip competence is reached. W. R. Proffit. Contemporary orthodontics. Fifth edition, 2013 Size of nose and chin nonextraction
move incisors forward extraction
retract incisors Teeth prominence More prominent Less prominent Soft tissue thickness An individual with thick, full lips looks good with incisor prominence that would not be acceptable in someone with thin, tight lips. Periodontal considerations Fenestration of the alveolar bone and stripping of the gingiva become increasingly likely as the incisors are advanced. Periodontal considerations Yared et al found that proclining the mandibular incisors more than 95° with decreased gingival thickness of less than 0.5 mm increased the severity and the amount of recession. K.F.G. Yared, E.G. Zenobio, W. Pacheco. Periodontal status of mandibular central incisors after orthodontic proclination in adults.(Am J Orthod Dentofacial Orthop 2006;130:6) Amount of crowding Guidelines for orthodontic extraction in Class I crowding cases can be summarized as follows: W. R. Proffit. Contemporary orthodontics. Fifth edition, 2013 < 4 mm 5-9 mm >10 mm Extraction is rarely indicated, only if severe incisor protrusion Extraction
Expansion Extraction Curve of Spee Does premolar extraction result in higher incidence of TMD?!! R.P. McLaughlin, J.C. Bennett . The extraction-nonextraction dilemma as it relates to TMD. (Angle Orthod 1995; 3: 175-186) The extraction of teeth as part of an orthodontic treatment plan does not increase the risk of TMD. J.A. McNamara. Orthodontic treatment and temporomandibular disorders. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 1997;83:107-17) Does Premolar extraction cause a decrease in vertical dimension?!! R.P. McLaughlin, J.C. Bennett. The extraction-nonextraction dilemma as it relates to TMD. (Angle Orthod 1995; 3: 175-186) L. Kocadereli. The effect of first premolar extraction on vertical dimension. (Am J orthod dentofacial orthop 1999;116:41-45) Is there an "extraction face"?!! S. J. Burrow. The Impact of Extractions on Facial and Smile Aesthetics. (Semin Orthod 2012;18:202-209) "The extraction versus nonextraction decision, if based on sound diagnostic criteria, does not have a systematic detrimental effect on facial profile." S.E. Bishara, D.M. Cummins, A.R. Zaher. Treatment and posttreatment changes in patients with Class II, Division I malocclusion after extraction and nonextraction treatment. (Am J Orthod Dentofacial Orthop 1997; 111:18-27) R.P. McLaughlin, J.C. Bennett. The extraction-nonextraction dilemma as it relates to TMD. (Angle Orthod 1995; 3: 175-186) Conclusion For enhanced facial attractiveness, some patients need extractions, whereas others can be treated without extractions. Diagnostic error
Error in treatment mechanics Careful diagnosis followed by evidence-based treatment decisions. Discuss the pros and cons with the patient before making the expansion-extraction decision. How the clinician decides when to extract and when not to extract is a matter that should depend on the needs of the patient. Extraction- Expansion Debate Carefully planned extractions Stability Appearance T.M. Graber. Orthodontics: current principles and techniques. Fifth edition, 2012 The space required to level the curve of Spee should be considered when calculating the space discrepancy. K.S. Al-Nimri. Vertical Changes in Class II division 1 Malocclusion after Premolar Extractions (Angle Orthod 2006;76:52–58.) The esthetic value of the “non-extraction only” treatment approach is not supported by current scientific research, although it is used as a marketing tool. Orthodontic setup features considerable advantages, especially in borderline cases.... Using a setup, treatment plans become less speculative... Araújo TM, Fonseca LM, Caldas LD, Costa-Pinto RA. Preparation and evaluation of orthodontic setup. (Dental Press J Orthod. 2012; 17:146-65) Diagnostic setup