Comparison of achieved and predicted crown movement in adults after 4 first premolar extraction treatment with Invisalign

ABSTRACT Objective: The effect of total arch distalization using orthodontic mini-implants (OMIs) combined with interproximal stripping (IPS) and second premolar extraction was investigated in Class I malocclusion patients. Materials and Methods: A total of 66 consecutively treated Class I malocclusion (Class I molar relationship; 0 mm < overbite and overjet < 4.5 mm) patients ranging in age from 17 to 44 years who received single-phase treatment were included in this study. Pre- and posttreatment lateral cephalograms and dental casts were measured and compared statistically. Results: In the distalization with IPS group, 3.6 mm and 3.8 mm of crowding in the upper and lower arches, respectively, were resolved, and 3.8 mm and 3.2 mm of upper and lower incisor retraction, respectively, were achieved simultaneously by the treatment. As a result of the second premolar extraction treatment, 3.9 mm and 3.6 mm of crowding in the upper and lower arches, respectively, were resolved, and 3.3 mm and 3.2 mm of incisor retraction, respectively, were achieved during treatment. There was no statistically significant difference in the amount of crowding and incisor retraction between the two groups. Conclusions: Total arch distalization using an OMI with IPS did not yield a significantly different treatment result compared to second premolar extraction treatment.

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Effect of Incisor Angulation on Overjet and Overbite in Class II Camouflage Treatment

The Angle Orthodontist ◽

10.2319/111206-460.1 ◽

2007 ◽

Vol 77 (6) ◽

pp. 1011-1018 ◽

Cited By ~ 16

Author(s):

Yasinee Sangcharearn ◽

Christopher Ho

Keyword(s):

Class Ii ◽

Regression Coefficients ◽

Lower Incisor ◽

Skeletal Class ◽

Premolar Extraction ◽

Anterior Teeth ◽

Skeletal Class Ii ◽

Set Up ◽

Extraction Treatment ◽

Lower Incisors

Abstract Objectives: To determine the amount of variation in overjet and overbite that may result from changes in upper and lower incisor angulations following upper first premolar extraction treatment in Class II malocclusions. Materials and Methods: Typodonts were set up to simulate a skeletal Class II occlusion treated with upper first premolar extractions. The upper incisor angulation was altered through a range from 100° to 120° to the palatal plane by 2° increments. The overjet and overbite were measured with every 2° of upper incisor angulation change. A regression analysis was performed on the experimental data, and the regression coefficients, slope, and intercept were estimated. Results: Excessive proclination of the lower incisors will result in an abnormal overjet and overbite relationship for any magnitude of upper incisor angulation. A normal lower incisor angulation facilitates the attainment of an optimal occlusion. Excessive palatal root torque of the upper incisors will result in an increase in overjet and a consequent decrease in overbite. If the upper incisors are excessively retroclined, an edge-to-edge incisor relationship will result. Conclusion: Class II camouflage treatment with upper first premolar extractions requires correctly angulated incisors to achieve optimal buccal segment interdigitation and incisor relationship. Labial root torque and interproximal reduction of the lower anterior teeth should be considered when the lower incisors are excessively proclined.

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Comparison of temporary anchorage devices and transpalatal arch-mediated anchorage reinforcement during canine retraction

European Journal of Dentistry ◽

10.4103/1305-7456.195163 ◽

2016 ◽

Vol 10 (04) ◽

pp. 512-516 ◽

Cited By ~ 1

Author(s):

Defne Kecik

Keyword(s):

Vertical Movement ◽

Premolar Extraction ◽

Canine Retraction ◽

Temporary Anchorage Devices ◽

Attached Gingiva ◽

Molar Teeth ◽

Skeletal Effects ◽

Bimaxillary Protrusion ◽

Transpalatal Arch ◽

Extraction Treatment

ABSTRACT Objective: The purpose of this study was to compare the dental and skeletal effects of canine retraction using conventional anchorage reinforcement systems and comparing them with the usage of TADs. Materials and Methods: The sample consisted of 50 patients having Class I malocclusions with bimaxillary protrusion indicated for first premolar extraction, and allocated into two groups. The first group consisted of 25 patients with a mean age of 18,7 years (min:14, max:22 years, 16 girls and 9 boys) that TADs were applied as an anchorage mechanic between attached gingiva of upper second premolar and first molar teeth. The second group consisted of 25 patients with a mean age of 19,4 years (min:15, max:23 years, 14 girls and 11 boys) that conventional molar anchorage with Transpalatal arch (TPA) was applied for the anchorage mechanics against canine retraction. Results: The results showed that mean mesial movement and the tipping of the first molars in TAD group between T0 - T1 were insignificant (P > 0,05), however in the TPA group were significant (P<0,01). Vertical movement of the molars were not significant when two groups were compared (P>0,05). Conclusion: Although TPA is a useful appliance, it doesn't provide an effective anchorage control on anteroposterior movement maxillary first molar teeth concerning first premolar extraction treatment. TADs are more convenient to provide absolute anchorage during maxillary canine retraction in contrast to transpalatal arch.

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Comparison of achieved and predicted tooth movement of maxillary first molars and central incisors: First premolar extraction treatment with Invisalign

The Angle Orthodontist ◽

10.2319/090418-646.1 ◽

2019 ◽

Vol 89 (5) ◽

pp. 679-687 ◽

Cited By ~ 7

Author(s):

Fan-Fan Dai ◽

Tian-Min Xu ◽

Guang Shu

Keyword(s):

Tooth Movement ◽

Inverse Correlation ◽

Stable Region ◽

Linear Mixed Effect Model ◽

Mixed Effect Model ◽

Mixed Effect ◽

Premolar Extraction ◽

Effect Model ◽

Incisor Retraction ◽

Extraction Treatment

ABSTRACT Objectives: To compare achieved and predicted tooth movements of maxillary first molars and central incisors in first premolar extraction cases treated with Invisalign. Materials and Methods: The present study included 30 patients who received maxillary first premolar extraction treatment with Invisalign. The actual posttreatment model was registered with the pretreatment model on the palatal stable region and superimposed with the virtual posttreatment model. Achieved and predicted tooth movements of maxillary first molars and central incisors were compared using paired t-test. Linear mixed-effect model analyses were used to explore the influence of age (adolescents vs adults), attachment (G6-optimized vs 3-mm vertical, 3-mm horizontal, and 5-mm horizontal), and initial crowding on the differences between predicted and achieved tooth movement (DPATM). Results: First molars achieved greater mesial tipping, mesial translation, and intrusion than predicted. Central incisors achieved less retraction and greater lingual crown torque and extrusion than predicted. Adolescents showed greater DPATM in the mesiodistal translation of first molars and labiolingual translation of central incisors and smaller DPATM in the occlusogingival translation of the first molars and crown torque of the central incisors than adults. The 3-mm vertical attachment group showed greater DPATM in the mesiodistal translation of the first molars vs the G6-optimized attachment group. Initial crowding had an inverse correlation with DPATM in angulation and mesiodistal translation of the first molars. Conclusions: First molar anchorage control and central incisor retraction were not fully achieved as predicted in first premolar extraction treatment with Invisalign. Age, attachment, and initial crowding affected the differences between predicted and achieved tooth movement.

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