1. The extraction of a lower incisor in orthodontic treatments www. orthofree.com www. orthofree.com www. orthofree.com

2. indications Angle class one Molar relationship with arch lenth- tooth size discrepancy from 4 to 7 mm, normal upper arch that does not need premolar extractions. Angle class one Molar relationship with arch lenth- tooth size discrepancy from 4 to 7 mm, normal upper arch that does not need premolar extractions. Bolton discrepancy with mandibular excess of 4 to 6 mm. Bolton discrepancy with mandibular excess of 4 to 6 mm. When lower expansion is impossible or compromising for periodontal health (risk of gingival recession) When lower expansion is impossible or compromising for periodontal health (risk of gingival recession)

3. indications Angle class one biprotrusion with lower front crowding. Class two by maxillary squeletal protrusion with lower incisors crowding. Mild squeletal class three. Orthodontic retreatment for relapsing lower anterior crowding…

4. Advantages Extracting one incisor rather then 4 premolars, less teeth are sacrificed Extracting one incisor rather then 4 premolars, less teeth are sacrificed Shorter treatment time with fixed appliances. The tooth movement needed is therefore minimal. Shorter treatment time with fixed appliances. The tooth movement needed is therefore minimal. Lower incisor extraction is a compromise solution for adults who need a relatively fast outcome. Lower incisor extraction is a compromise solution for adults who need a relatively fast outcome. No negative consequences on soft tissue profile. No negative consequences on soft tissue profile.

5. Disadvantages Acceptable aesthetic result but the occlusion is not always a perfect class one. Acceptable aesthetic result but the occlusion is not always a perfect class one. Lower midline deviation. Lower midline deviation. Formation of a black triangle due to papillear defect between lower incisors. Formation of a black triangle due to papillear defect between lower incisors.

6. counterindications Angle class II division 2 with deep overbite. Tooth size- arch length discrepancy where premolar extractions are more convenient. Important class II or class III squeletal discrepancy.

7. Complimentary exams Study casts Study casts X- Rays X- Rays Set Up Set Up

8. Chosing the tooth to be extracted. The most malpositioned tooth or the one with gingival defect ( gum recession)

9. Pathological Extraction of the 32 and fracture and important apical lesion on 32 and 33. Kenza LAHLOU, Aalloula EL HOUSSAINE

10. Clinical case 1:class III tendency.

11. ROSS J. MILLER, TRANG T. DUONG, MITRA DERAKHSHAN Clinical case 2 : Biprotrusion

12. Clinical case 3: José Roberto Oliveira FLORIACH Ewaldo Luiz de ANDRADE José Roberto Oliveira FLORIACH Ewaldo Luiz de ANDRADE

13. Clinical case 4 : lower incisor with pathology Zachrisson, Keim

14. Clinical case Zachrisson, Keim

15. Closure of extraction space Reinaldo Mazzottini

16. Biprotrusion Kenza LAHLOU, Aalloula EL HOUSSAINE

17. Thousand years old Oak tree.

18. Bibliography BIONDI Giovanni, via Don Pastega 8, 31052 Varago di Maserada (TV), Italie.International BIONDI Giovanni, via Don Pastega 8, 31052 Varago di Maserada (TV), Italie.International Orthodontics Vol 4, N° 1 - mars 2006pp. 63-72 Doi : ORT-03-2006-4-1-1761-7227 Orthodontics Vol 4, N° 1 - mars 2006pp. 63-72 Doi : ORT-03-2006-4-1-1761-7227 101019-20060162 101019-20060162 ROSS J. MILLER, TRANG T. DUONG,MITRA DERAKHSHAN VOLUME XXXVI NUMBER 2 © 2002 JCO, Inc. Zachrisson Keim, VOLUME XXXIX NUMBER 4 © 2005 JCO, Inc. FLORIACHE José Roberto Oliveira waldo Luiz de ANDRADE, Heterodox extractions analysis on the malocclusions treatment PINTO, M. R.; MOTTIN, L. P.; DERECH, C. D.; ARAÚJO, M. T. S,R Dental Press Ortodon Ortop Facial 118 Maringá, v. 11, n. 1, p. 114-121, jan. /f ev. 2006 Mazzottini Reinaldo R Clin Ortodon Dental Press, Maringá, v. 4, n. 5 - out./nov. 2005 LAHLOU Kenza, Aalloula EL HOUSSAINE Rev Odont Stomat 2008;37:59-72