An interventional study of MAMP therapy with MARPE expander and MAMP therapy with Hyrax expander in Malocclusion, Angle Class III and Crossbite (Anterior) (Posterior), sponsored by University of Sao Paulo. Completed at 1 site in Brazil. Open to participants aged 9 Years to 13 Years. Per ClinicalTrials.gov, last updated 2021-05-12.
Sponsored by University of Sao Paulo · Not applicable, Interventional, and Treatment
This study evaluates the dentoskeletal effects produced by two maxillary protraction protocols in adolescent patients. Half of participants will be treated with a tooth-borne and tooth-bone-borne expanders as anchorage in the maxillary arch. Miniscrews will be used as anchorage in the mandibular arch for both groups.
Class III malocclusion treatment in growing patients is challenging. A new treatment for maxillary protraction using skeletal anchorage reported an efficient maxillary protraction in the late mixed dentition an early permanent dentition. Therefore, the aim of this study is to compare the dentoskeletal effects produced by two maxillary protraction protocols anchored on miniscrews.
The sample will be recruited at the Orthodontic Clinic of Bauru Dental School, University of São Paulo, Brazil. A sample of thirty-five patients, between 9 and 13 years old will be selected. The inclusion criteria are: Class III malocclusion associated with anterior crossbite. The participants will be allocated into 2 groups. Group 1 will comprise 20 individuals treated with a tooth-bone-borne expander and 2 miniscrews in the mandible Group 2 will comprise 15 individuals treated with a tooth-borne expander and 2 miniscrews in the mandible. Digital models and cone-beam computed tomography (CBCT) will be obtained before (T1) and 12 months after treatment (T2). Occlusal radiographs and partial (canine to canine) models will be obtained before and immediately after expansion. Two-dimensional cephalometric evaluations will be performed in the Dolphin® software. The arch width, arch perimeter and arch length will be analyzed with the Orthoanalyzer® software. Three-dimensional superimposition at the cranial base of T1 and T2 CBCT images will be performed. The inter incisor diastema will be evaluated by occlusal radiographs and dental models. Discomfort, pain and quality of life will evaluated by questionnaires. After verifying the normal distribution, the intragroup comparison will be performed with paired t test and intergroup comparison will be performed with t test. In the case of lost to follow-up patients, intention to treat analysis will be used. A significance level of 5% will be regarded for all tests.
Temporary pain and discomfort are possible after the installation of the miniscrews. Patients and legal guardians will be informed. After the consent, the treatment can be stoped at any time.
57 studies on the registry are indexed under Malocclusion, Angle Class III; 11 are open to participants now.
This study's enrollment of 35 is close to the median of 32 across 53 interventional studies indexed under Malocclusion, Angle Class III.
Browse Malocclusion, Angle Class III studies →University of Sao Paulo is the lead sponsor of 1,035 studies on the registry; 95 are open to participants now.
Of its 8 completed or terminated interventional studies of FDA-regulated products, 0 (0%) have results posted.
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Exclusion Criteria:
The experimental group will comprise 20 patients submitted to miniscrew anchored maxillary protraction (MAMP) with a tooth-bone-borne expander as anchorage in the maxillary arch. The miniscrew assisted rapid palatal expander (MARPE) will be used.
Device: MAMP therapy with MARPE expander
The active comparator group will comprise 15 patients submitted to miniscrew anchored maxillary protraction (MAMP) with a tooth-borne expander as anchorage in the maxillary arch. The conventional hyrax expander will be used.
Device: MAMP therapy with Hyrax expander
Twenty patients will be submitted to MAMP therapy with MARPE expander as anchorage in the maxillary arch. The appliance anchorage will be provided by bands adapted on the maxillary first permanent molars and circumferential clamps in the maxillary canines or premolars. The maxillary and mandibular miniscrews will be placed in the same section. After a 24-hour period, parents will be oriented to activate the expander screw. Patients will be instructed to wear intermaxillary elastics connecting the maxillary first molar hooks to the mandibular mini-implants.
Fifteen patients will be submitted to MAMP therapy with Hyrax expander as anchorage in the maxillary arch. The appliance anchorage will be provided by bands adapted on the maxillary first permanent molars and circumferential clamps in the maxillary canines or premolars. The mandibular miniscrews will be placed and after a 24-hour period, parents will be oriented to activate the expander screw. Patients will be instructed to wear intermaxillary elastics connecting the maxillary first molar hooks and the mandibular mini-implants.
Maxillary sagittal skeletal discrepancy
CBCT exams will be obtained before (T1) and after treatment (T2). Reformatted lateral cephalometric images will be obtained using Dolphin software for comparisons with conventional cephalograms. The maxillary sagittal skeletal discrepancy will be observed using the variables: SNA, Co-A, Condylion to ANS and others.
Time frame: 12 months
Mandibular sagittal skeletal discrepancy
CBCT exams will be obtained before (T1) and after treatment (T2). Reformatted lateral cephalometric images will be obtained using Dolphin software for comparisons with conventional cephalograms. Mandibular sagittal skeletal discrepancy will be observed using the variables: Co-Gn, SNB, Gonial/Jaw Angle and others.
Time frame: 12 months
Vertical skeletal discrepancy
CBCT exams will be obtained before (T1) and after treatment (T2). Reformatted lateral cephalometric images will be obtained using Dolphin software for comparisons with conventional cephalograms. Vertical skeletal discrepancy will be observed using the variables: Occ Plane to SN, NF - FH (PP-FH), SN - GoGn, SN- Palatal Plane and others.
Time frame: 12 months
Teeth discrepancy
CBCT exams will be obtained before (T1) and after treatment (T2). Reformatted lateral cephalometric images will be obtained using Dolphin software for comparisons with conventional cephalograms. Teeth discrepancy will be observed using the variables: Overjet, Overbite, Interincisal Angle (U1-L1), Molar Relation, Mesial Molar Relationship, U1 - Palatal Plane, IMPA and others.
Time frame: 12 months
Soft tissue discrepancy
CBCT exams will be obtained before (T1) and after treatment (T2). Reformatted lateral cephalometric images will be obtained using Dolphin software for comparisons with conventional cephalograms. Soft tissue discrepancy will be observed using the variables: Nasolabial Angle (Col-Sn-UL), Upper Lip to E-Plane, Lower Lip to E-Plane, Upper Lip - S line, Lower Lip - S line and others.
Time frame: 12 months
Maxillary and mandibular inter-first permanent molar distances
Arch dimensions will be measured in digital dental models obtained before (T1) and after treatment (T2).
Time frame: 12 months
Maxillary and mandibular intercanine distances
The intercanine distance will be measured in digital dental models obtained before (T1) and after treatment (T2).
Time frame: 12 months
Maxillary and mandibular dental arches perimeters
Arch perimeter will be measured in digital dental models obtained before (T1) and after treatment (T2).
Time frame: 12 months
Maxillary and mandibular dental arches lengths
Arch lenght will be measured in digital dental models obtained before (T1) and after treatment (T2).
Time frame: 12 months
Inclination of maxillary and mandibular first permanent molars
Teeth inclination will be measured in digital dental models obtained before (T1) and after treatment (T2).
Time frame: 12 months
Amount of interincisor diastema
The interincisor diastema will be measured in the occlusal radiograph and partial model obtained immediately after expansion.
Time frame: 7 days
Three-dimensional changes
Three-dimensional changes will be observed by the cranial base superimposition of the CBCT exams obtained before (T1) and after treatment (T2).
Time frame: 12 months
Discomfort and pain
Discomfort and pain will be evaluated using a visual analog scale of 10-cm, where 0-cm is no discomfort/pain and 10-cm is the greatest discomfort/pain.
Time frame: 1 month
Parents perception of pain
Parents perception of pain will be evaluated using a visual analog scale of 10-cm, where 0-cm is no discomfort/pain and 10-cm is the greatest discomfort/pain.
Time frame: 1 month
Quality of life evaluation
CPQ (Child Perceptions Questionnaires) will be used to evaluated quality of life. The CPQ8-10 and CPQ11-14 will be applied before (T1), during and after (T2) treatment for patients of both groups.
Time frame: 12 months
Plan to share: No
Ran from Jun 2017 to primary completion in Aug 2019, 26 months.
Of 37 non-industry interventional studies with no phase under Malocclusion, Angle Class III, half reached primary completion within 13 months of starting (the median), counting those still running; a quarter within 10 and three quarters within 26. This study's 26 months is above that.
Counting every sponsor, half of 38 studies reached it within 13 months; a quarter within 10 and three quarters within 26.
How these figures are worked out, and which studies are left out of them.
This study is completed, as verified in May 2021. You cannot join it, but the record below documents what was studied.
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