Miniscrews as Anchorage Device for Orthodontic Treatment

Region Gävleborg

Status: Completed

Conditions: Orthodontic Anchorage Procedures; Orthodontic Space Closure

Treatments: Procedure: Extraction of the maxillary first premolars; Device: Spider Screw K1 short neck; Drug: Topical anesthesia (buccal); Drug: Local anesthesia (buccal); Device: Molarblock; Drug: Local anesthesia (buccal and palatal); Drug: Topical anesthesia (buccal and palatal)

Study type: Interventional

Funder types: Other

Identifiers

NCT02644811

CFUG-479851

Details and patient eligibility

About

The purpose of this trial is to study and compare two different anchorage techniques. Adolescent patients in need for orthodontic treatment are randomized into Group A and B. Both groups are treated with extractions of the maxillary first premolars and fixed appliance. Anchorage is reinforced by miniscrews in Group A and by molarblock in Group B.

The hypotheses are:

• that placement of miniscrews does not cause more pain or discomfort than premolar extractions
• that molarblock provides increase of anchorage
• that miniscrews have a better anchorage capacity than molarblock
• that miniscrews are more cost-efficient than conventional anchorage techniques

Full description

Participants are recruited from the orthodontic specialist clinic in Gävle, Sweden. After informed consent participants are randomized into Group A and B. The treatment starts with extractions of the maxillary first premolars. Extractions are performed by the participants´ general practitioner. Orthodontic treatment starts after the tooth extractions.

All participants get treatment with fixed appliance according to the straight wire concept (3M Victory brackets, .022 slot size, McLaughlin-Bennet-Trevesi prescription). The recommended wire sequence is: .016 Heat Activated Nickel Titanium, .019x.025 Heat Activated Nickel Titanium, .019x.025 Stainless Steel. Treatment time is about two years.

The following measurements are taken at:

T0 (Before treatment start): Study models, baseline questionnaire,

T1 (after tooth extractions, before the orthodontic treatment): Study models, cephalographic x-ray, questionnaire at the evening after tooth extractions, questionnaire one week after tooth extractions.

T2 (After miniscrew placement (Group A), Before space closure): Study models, cephalographic x-ray, questionnaire at the evening after miniscrew placement, questionnaire one week after miniscrew placement.

T3 (After space closure and miniscrew removal): Study models, cephalographic x-ray, questionnaire after screw removal

Enrollment: 80 patients

Sex: All

Ages: 11 to 20 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• Adolescents in need of orthodontic treatment with fixed appliance including extractions of the maxillary first premolars
• Need for Anchorage reinforcement
• Permanent dentition including the maxillary second molars in occlusion (DS4M2 according to Björk)
• Regular dental care in Sweden since the age of three.

Exclusion criteria

• Experience of previous orthodontic treatment
• Need for orthognathic surgery
• Need for maximum anchorage.

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Single Blind

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80 participants in 2 patient groups

Group A - Miniscrews

Experimental group

Description:

Topical anesthesia (buccal and palatal) followed by local anesthesia (buccal and palatal). Extraction of the maxillary first premolars. Fixed appliance in the maxilla or maxilla and mandible. Anchorage reinforcement with miniscrews (Spider Screw K1 short neck). Miniscrews are placed buccally between the maxillary second premolar and the first molar after topical anesthesia (buccal) and injection (buccal). Miniscrews are placed when space closure starts. Space closure is performed as en masse retraction. Miniscrew are immediately loaded with 150g Nickel Titanium coil springs.

Treatment:

Drug: Local anesthesia (buccal and palatal)

Drug: Topical anesthesia (buccal and palatal)

Drug: Local anesthesia (buccal)

Drug: Topical anesthesia (buccal)

Device: Spider Screw K1 short neck

Procedure: Extraction of the maxillary first premolars

Group B - Molarblock

Active Comparator group

Description:

Topical anesthesia (buccal and palatal) followed by local anesthesia (buccal and palatal. Extraction of the maxillary first premolars. Fixed appliance in the maxilla or maxilla and mandible. Anchorage reinforcement with molarblocks - a Stainless steel ligature connecting the maxillary second premolar with the maxillary first and second molar. Molarblocks are installed from the beginning of leveling and alignment. Space closure is performed as en masse retraction with type one active tie-backs.

Treatment:

Drug: Local anesthesia (buccal and palatal)

Drug: Topical anesthesia (buccal and palatal)

Device: Molarblock

Procedure: Extraction of the maxillary first premolars