Treatment Effects of Herbst Appliance in Skeletal Class II Cases During Prepubertal and Postpubertal Periods

Study Overview
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Brief Summary
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The study was directed to compare the treatment outcomes of subjects with Class II malocclusion who were treated with Herbst appliance before and after puberty.

Detailed Description
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Thirty-six Class II patients were randomly selected and divided into two groups based on their stage of skeletal maturation: pre-pubertal group (18 patients, mean age 9.15± 1.5 years) and post-pubertal group (18 patients, mean age 16.3 ± 1.0 years). All patients were treated with metallic splint supported Herbst IV appliance. Pretreatment and post-Herbst IV treatment cone beam CT(CBCT) scans were obtained for both groups. Dentoskeletal and TMJ measurements made on the CBCT scans were analysed.

Official Title
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Treatment Effects of Herbst Appliance in Skeletal Class II Cases During Prepubertal and Postpubertal Periods: A Cone Beam Computed Tomographic Study

Conditions
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Class II Malocclusion, Division 1

Intervention / Treatment
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* Device: Herbst appliance


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Skeletal Class II malocclusion with retrognathic mandible (ANB >5°, SNB<76°) Normal growth pattern (SN/MP angle was in 25°- 35° range) Unilateral or bilateral Class II molar relationship greater than or equal to one-half a cusp width. Minimal or no crowding in the mandibular arch (0-5mm). Average inclination or slight retroclination of the lower incisor. An overjet greater than 5 mm. Exclusion Criteria: Skletal Class I Craniofacial syndrome.

Ages Eligible for Study
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Minimum Age: 8 Years
Maximum Age: 17 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: pre-pubertal group.<br>The patients were allocated into the pre-pubertal group based on their skeletal stage of maturation using the modified cervical vertebrae maturation Staging (CVMS) with skeletal maturity stages of CVMS II and CVMS III | Device: Herbst appliance<br>* The bottom line of the study is to investigate the changes after Herbst appliance treatment and relate it to the pubertal status of the skeletal class II patients using CBCT.<br>|
| Experimental: post-pubertal group<br>The patients were allocated into the post-pubertal group based on their skeletal stage of maturation using the modified cervical vertebrae maturation Staging (CVMS) with skeletal maturity stages of CVMS V and CVMS IV | Device: Herbst appliance<br>* The bottom line of the study is to investigate the changes after Herbst appliance treatment and relate it to the pubertal status of the skeletal class II patients using CBCT.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Skeletal and dental changes | The DICOM (Digital Imaging and Communications in Medicine) files from the pre and post CBCT scans were imported to Mimics software (Version 10.1, Materialise NV, Leuven, Belgium); and the cephalometric landmarks and planes were defined . Linear sagittal measurements of point A, point B, glenoid fossa, upper incisor, lower incisor, upper molars, and lower molars were recorded in relation to orbital perpendicular plane. | 8 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Condylar head position | The Most middle-superior point of the mandibular condyle was determined in sagittal, axial and coronal views. In the sagittal slice of the middle condylar head, a line was drowned through the widest measurement of the condylar heads visible on the slice, from this line, three lines were raised crossing the glenoid fossa at 45°, 90°, and 135° . Four linear measurements representing the anterosuperior, superior, posterosuperior, and posterior distance were taken from the glenoid fossa wall to the surface of the condyle | 8 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Class II malocclusion., prepubertal patients., postpubertal patients., Herbst appliance.