Miniscrews as Anchorage Device for Orthodontic Treatment

Region Gävleborg80 enrolled

Overview

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

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

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

Interventions

Topical anesthesia (buccal and palatal)DRUG

Saliva is removed with a sterile swab followed by application of 5% Lidocaine gel (APL, Sweden) on the gingiva.

Local anesthesia (buccal and palatal)DRUG

Injection of 1,5 ml Xylocaine Dental Adrenaline (Lidocaine hydrochloride 20 mg/ml, adrenaline 12.5 µg/ml, Dentsply Pharmaceutical, Weybridge, Surrey, UK).

Extraction of the maxillary first premolarsPROCEDURE

Careful extraction of the maxillary first premolars after mobilization.

Topical anesthesia (buccal)DRUG

Saliva is removed with a sterile swab followed by application of 5% Lidocaine gel (APL, Sweden) on the gingiva.

Local anesthesia (buccal)DRUG

Injection of 0.3 ml Xylocaine Dental Adrenaline (Lidocaine hydrochloride 20 mg/ml, adrenaline 12.5 µg/ml, Dentsply Pharmaceutical, Weybridge, Surrey, UK).

MolarblockDEVICE

Molarblock is a Stainless steel ligature connecting the maxillary second premolar with the maxillary first and second molar.

Spider Screw K1 short neckDEVICE

The Spider Screw K1 (Health Development Company, Sarcedo, Italy) is a self-drilling and self-tapping screw. Short neck screws (SCR-1508 and SCR-1510) with a diameter of 1.5 mm and length 8 or 10 mm are used.

Eligibility

Sex: ALLMin age: 11 YearsMax age: 20 YearsHealthy volunteers:

Medical Language ↔ Plain English

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.

Outcomes

Primary Outcomes

Change in Tooth Position of the Maxillary Molars During Space Closure

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

Time frame: Through Space Closure (T2-T3), an average of 9 months

Secondary Outcomes

Experience of Pain and Discomfort

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

Time frame: Baseline, the evening after tooth extractions, one week after tooth extractions, the evening after miniscrew placement, one week after miniscrew placement

Change in Tooth Position of the Maxillary Molars During Levelling and Alignment

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

Time frame: Through Levelling and Alignment (T1-T2), an average of 9 months

Societal Costs

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.

Time frame: Through Study Completion, an average of 2 years