<abstract xmlns="http://www.w3.org/1999/xhtml">

<p>The first molar has been reported to be the most caries prone tooth in the permanent dentition. Rarely is the extraction of the four first molars the ideal choice in orthodontic treatment, especially the extraction of four molars and four premolars. However, the extraction program presents a treatment alternative in selected cases. In the following case report, the orthodontic treatment is described a 15-year-old male patient who presented with a dentoskeletal bimaxillary protrusion, and a chief complaint of”crooked teeth”. Moreover, the patient had a skeletal Class I malocclusion with crowded dentitions, a hyperdivergent growth pattern, deviated midlines and an extremely deep Curve of Spee. A satisfactory treatment outcome was obtained by the extraction of four premolars and four compromised first molars. The mechanics involved alignment, levelling, detailing the occlusion using a straight arch wire technique followed by retention. The active treatment time was 48 months. The treatment successfully achieved a bilateral Class I relationship of the canines and the right molars, a mild Class III relationship of the left molars, a normal overjet and overbite, aligned dental midlines, optimal intercuspation and a harmonious facial profile. The occlusion remained stable during 5 years of review.</p>
</abstract>

The first molar has been reported to be the most caries prone tooth in the permanent dentition. Rarely is the extraction of the four first molars the ideal choice in orthodontic treatment, especially the extraction of four molars and four premolars. However, the extraction program presents a treatment alternative in selected cases. In the following case report, the orthodontic treatment is described a 15-year-old male patient who presented with a dentoskeletal bimaxillary protrusion, and a chief complaint of”crooked teeth”. Moreover, the patient had a skeletal Class I malocclusion with crowded dentitions, a hyperdivergent growth pattern, deviated midlines and an extremely deep Curve of Spee. A satisfactory treatment outcome was obtained by the extraction of four premolars and four compromised first molars. The mechanics involved alignment, levelling, detailing the occlusion using a straight arch wire technique followed by retention. The active treatment time was 48 months. The treatment successfully achieved a bilateral Class I relationship of the canines and the right molars, a mild Class III relationship of the left molars, a normal overjet and overbite, aligned dental midlines, optimal intercuspation and a harmonious facial profile. The occlusion remained stable during 5 years of review.

A patient with bimaxillary protrusion was treated by the extraction of four premolars and four compromised first molars: a case report

Australasian Orthodontic Journal

This work is licensed under the Creative Commons Attribution 4.0 International License.

The first molar has been reported to be the most caries prone tooth in the permanent dentition. Rarely is the extraction of the four first molars the ideal...

	Chinese norm	Pre-treatment	Post-treatment
SNA (°)	82.8 ± 4.0	80.6	80.1
SNB (°)	80.1 ± 3.9	77.2	77.6
ANB (°)	2.7 ± 2.0	3.4	2.5
NA-PA (°)	6.0 ± 4.4	7.5	4.7
FMA (°)	31.3 ± 5.0	31.7	31.9
SN-MP (°)	31.1 ± 5.6	37.8	38.3
U1-SN (°)	105.7 ± 6.3	118.7	107.4
U1-NA (mm)	5.1 ± 2.4	11.2	3.0
L1-MP (°)	92.6 ± 7.0	91.4	85.5
L1-NB (mm)	6.7 ± 2.1	10.5	4.0
Interincisal angle (°)	125.4 ± 7.9	111.7	127.5
Y-axis angle (°)	65.8 ± 4.2	68.6	64.3
Overbite (mm)	0-3.0	3.6	0.8
Overjet (mm)	0-3.0	6.0	1.9
Upper lip to E-line (mm)	-1.0 ± 2.0	4.0	-1.4
Lower lip to E-line (mm)	0.0 ± 2.0	7.8	-0.2

A patient with bimaxillary protrusion was treated by the extraction of four premolars and four compromised first molars: a case report

Publié en ligne: 01 mars 2024

Pages: 37 - 49

Reçu: 01 sept. 2023

Accepté: 01 déc. 2023

DOI: https://doi.org/10.2478/aoj-2024-0001

© 2024 Jiajun Deng et al., published by Sciendo

This work is licensed under the Creative Commons Attribution 4.0 International License.

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Cephalometric analysis