MedPath

Miniscrews as Anchorage Device for Orthodontic Treatment

Not Applicable
Completed
Conditions
Orthodontic Anchorage Procedures
Orthodontic Space Closure
Interventions
Drug: Topical anesthesia (buccal and palatal)
Drug: Local anesthesia (buccal and palatal)
Procedure: Extraction of the maxillary first premolars
Device: Molarblock
Drug: Topical anesthesia (buccal)
Drug: Local anesthesia (buccal)
Device: Spider Screw K1 short neck
Registration Number
NCT02644811
Lead Sponsor
Region Gävleborg
Brief Summary

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

Detailed 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

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
80
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.

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
Group A - MiniscrewsLocal anesthesia (buccal and palatal)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.
Group A - MiniscrewsExtraction of the maxillary first premolarsTopical 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.
Group B - MolarblockTopical anesthesia (buccal and palatal)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.
Group A - MiniscrewsSpider Screw K1 short neckTopical 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.
Group B - MolarblockMolarblockTopical 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.
Group A - MiniscrewsTopical anesthesia (buccal and palatal)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.
Group B - MolarblockExtraction of the maxillary first premolarsTopical 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.
Group A - MiniscrewsTopical anesthesia (buccal)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.
Group A - MiniscrewsLocal anesthesia (buccal)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.
Group B - MolarblockLocal anesthesia (buccal and palatal)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.
Primary Outcome Measures
NameTimeMethod
Change in Tooth Position of the Maxillary Molars During Space ClosureThrough Space Closure (T2-T3), an average of 9 months

Tooth movement is assessed in millimeters using superimposition of study models and lateral cephalograms.

Secondary Outcome Measures
NameTimeMethod
Experience of Pain and DiscomfortBaseline, the evening after tooth extractions, one week after tooth extractions, the evening after miniscrew placement, one week after miniscrew placement

Experiences of pain and discomfort are examined with validated self-report questionnaires.

Change in Tooth Position of the Maxillary Molars During Levelling and AlignmentThrough Levelling and Alignment (T1-T2), an average of 9 months

Tooth movement is assessed in millimeters using superimposition of study models and lateral cephalograms.

Societal CostsThrough Study Completion, an average of 2 years

Societal costs are the sum of direct and indirect treatment costs. Direct costs are treatment time in the clinic and used material. Indirect costs are travel costs and costs for parents following the participant to the clinic.

Trial Locations

Locations (1)

Specialisttandvården Ortodonti

🇸🇪

Gävle, Gävleborgs Län, Sweden

© Copyright 2025. All Rights Reserved by MedPath