An interventional study of Micro-osteoperforation and Conventional posterior segment intrusion in Anterior Open Bite Malocclusion, sponsored by Ain Shams University. Completed at 1 site in Egypt. Open to participants aged 18 Years to 30 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-08-12.
Sponsored by Ain Shams University · Not applicable, Interventional, and Treatment
This clinical trial aimed to assess the efficiency of micro-osteoperforation for accelerating posterior intrusion in open bite cases. A human sample of thirty subjects was divided into two groups ; Group I (MOP), posterior intrusion with micro-osteoperforation (MOP) and group II (Control), same intrusion protocol without micro-osteoperforation.
Instrument and procedures I. Diagnostic Procedures 1. Medical and dental history. 2. Comprehensive clinical examination. a. Extraoral examination. b. Intraoral examination. c. Functional examination. 3. Diagnostic records a. Photographs. b. Orthodontic study models. c. Lateral cephalometric records to verify the eligibility of the case. D. Analysis of records and treatment planning. Once the case fulfilled the inclusion criteria, full skull CBCT was taken before starting treatment. Interventions 1. Impression for fabrication of acrylic splint covering the occlusal surface of the whole maxillary posterior segment bilaterally. 2. Placement of miniscrews , two in each side, one placed in the Zygomatic buttress and the other one placed palatal to the first permanent molar. 3. Micro-osteoperforation using propel accelerator in Group I (MOP group). 4. Cementation of acrylic splint and force application using four closed coil spring on each side. 4. Follow up every four weeks and impression to measure amount of intrusion. III. Methods of data collection. 1. CBCT before intrusion, and CBCT after intrusion. 2. Digital models analysis. IV. Statistical Analysis.
I. Diagnostic Procedures Detailed and comprehensive patient diagnosis was performed guided by the evaluation sheet used at the Department of Orthodontics, Faculty of Dentistry, Ain Shams University. The diagnostic procedure included the following steps: 1. Medical and dental history Full history was obtained for each patient including patient's name, sex, age, chief complaint, medical and dental history. 2. Comprehensive clinical examination a. Extraoral examination Frontal examination included the examination of the patient's facial type, symmetry, vertical facial proportions, and lip competence. Smile examination comprised detailed smile analysis involving gingival display on smiling, smile arc, smile symmetry and width of buccal corridors. All the patients included in the study showed normal or increased gingival display on smiling. Profile examination incorporated the inspection of facial profile type, lip protrusion and nasolabial angle, lip competence and vertical facial proportions. b. Intraoral examination Full and detailed intraoral examination included number of teeth present in the oral cavity, oral hygiene, periodontal condition of all teeth, the presence of any caries, broken restorations, and missing teeth. Examining the malocclusion in all planes of space was performed as follows, in the anteroposterior plane, Angle molar classification, canine relationships and overjet were determined. In the vertical plane, amount of open bite was measured from the incisal edge of the maxillary central incisor to that of the mandibular central incisor. In the transverse plane, the midlines and the posterior occlusion were checked to determine any midline shift or presence of posterior crossbite. Arch form, palatal vault shape and depth were also clinically examined. Patients included in the study showed anterior open bite with class I or Class II molar relationship. c. Functional examination Patients were carefully examined to determine the mode of breathing. Mouth breathing patients were referred to ENT consultation to check for patency of airway and remove any causes of respiratory obstruction prior to treatment. Tongue examination was carefully performed at rest and during function (swallowing and speech) to determine the resting tongue posture and the presence of any tongue thrust habit during function. Those cases who needed habit breaking appliances were addressed during fixed treatment phase following the intrusion phase. 3. Diagnostic records A full set of orthodontic records was taken for every patient as part of the routine procedure for the treatment of patients in the outpatient clinic of the Orthodontic Department, Ain Shams University, including: a. Photographs• For each case, a full set of extraoral and intraoral photographs were taken. Extraoral photographs included frontal views (rest and smile), and profile view while intraoral photographs included frontal, right side, left side, and occlusal (maxillary and mandibular) views. All photographs were obtained via a 20.3 mega pixel digital camera. b. Orthodontic study models • Alginate impressions were taken for the upper and lower arches of each patient using suitable-sized perforated trays and alginate impression material mixed according to the manufacturer's instructions. Each impression was poured with improved orthodontic stone material. Wax bites were obtained using modelling pink wax in order to maintain proper occlusion during trimming to obtain articulated orthodontic study models. c. Orthodontic Radiographic records • Lateral cephalometric radiographs A lateral cephalometric radiographic image was taken for each patient and was used to measure several linear and angular measurements that determined growth pattern, steepness of mandibular plane and vertical dentoalveolar growth. Those measurements were analyzed for screening patient's eligibility for the study and to confirm the presence of vertical dysplasia. All the cases had posterior vertical dentoalveolar excess and anterior open bite.
All the previously gathered data were analyzed and once the diagnosis of the case fulfilled the inclusion criteria, the patient was given a full explanation for the treatment plan and was asked to sign a detailed written informed consent of agreement in which the aim of the study, the methodology and possible complications were clearly described.
Formulation of the problem list and treatment plan. All the previously gathered data were analyzed, then used to formulate the problem list and eventually develop the treatment plan. If the treatment plan included posterior segment intrusion to allow closure of open bite by mandibular autorotation, the patient was included in the study. Patients were then asked to sign a detailed written informed consent of agreement in which the aim of the study, the methodology and possible complications were clearly described. Patients were randomly allocated into the MOP or control groups, and intervention procedures were then started. II. Interventions Pretreatment Cone Beam Computed Tomography (CBCT). All patients enrolled in this study were imaged using the i-CAT CBCT scanner at the department of Oral Radiology, Faculty of Dentistry, Ain Shams University. The procedures completed in this study were as follows: Micro-osteoperforation (MOP) Group I, a duplicate was taken for the maxillary arch to fabricate the maxillary acrylic splint. miniscrew implants were inserted on both sides. Micro-osteoperforations were performed by Propel accelerator. The splint was cemented in place. Immediate intrusion force was applied using closed coil springs. The details are as follows: 1. Placement of four self-drilling and self-tapping Titanium TADs, with a size of 1.8 mm in diameter and 10 mm in length. They were placed at the following sites: two buccal implants placed bilaterally at the Zygomatic buttress area and the two palatal implants placed bilaterally at the palatal region. After palpating the Zygomatic buttress in the buccal sulcus apical to the mesiobuccal cusp of the maxillary first molar, a short vertical vestibular incision (1-1.5 cm in length) was made. The lower aspect of the Zygomatic process of the maxilla was exposed by blunt dissection, then the implant was inserted at the oblique area present between the horizontal and vertical shelves of the Zygomatic buttress just above the upper first molar, 14-16 mm above the maxillary occlusal plane , at an angle of 55-70° to the maxillary occlusal plane. An easy adaptable thick ligature wire (0.014) was ligated through the hole at the implant head to form a hook to facilitate attachment to the eyelets of the coil spring in case the implant gets covered by soft tissue overgrowth. The patients were instructed to follow strict oral hygiene instructions and the insertion site was allowed to heal for one week. After one week, the palatal miniscrew implants were inserted bilaterally at an anteroposterior position apical to the first molars (approximately at the mesiopalatal line angle), and mediolaterally at approximately 3mm to 5mm lateral to the median palatine. 2- At the same visit, micro-osteoperforations were performed in group I before by the Propel® Excellerator MOP device following the manufacturer instructions. Three MOPs were performed in a linear pattern at the buccal side, mesial and distal to the roots of all maxillary premolars and molars except distal to maxillary second molars due to lack of accessibility. The depth of perforations was adjusted based on the estimated thickness of the gingiva and alveolar bone ranging from 5 mm at the premolar region to 7 mm at the molar region. The perforations were made 2-3 mm away from apex of interdental papillae to avoid their damage and within the attached gingiva area to avoid soft tissue rolling around the micro-tip. 3- Appliance assembly and force application were initiated at the same visit after MOPs to benefit from the inflammatory reaction initiated by the minor bone injuries. Then it was cemented in place with temporary cement which provided good seal, low solubility and was easily removed during follow-up visits. Intrusion force was applied by Nickel-Titanium (Ni-Ti), medium force (150 g) closed coil springs. Four springs were attached on each side extending from the hooks of the appliance buccally and lingually at one end and to the zygomatic and palatal implants' head at the other end. The total force magnitude was 600 g per side, divided to 300 g from the buccal and palatal sides. This force was uniformly distributed via the acrylic splint along the long axis and over the root surface area of maxillary molars and premolars. The mandibular arch was stabilized by a vacuum retainer extending to the last distal tooth in the arch fabricated from thermoplastic sheets of 1 mm thickness to prevent compensatory eruption of mandibular molars during maxillary intrusion. The desired amount of activation was produced by controlling the length of the coil springs through ligation ties to adjust the length producing the required force on each side. 4-Follow-up The patients were recalled at two- and four-weeks intervals. At the two weeks recall visit, the coil springs were checked for their attachment integrity.
Every four weeks, the appliance was removed, and alginate impressions were taken for the upper arch. Those impressions were then poured in hard stone and scanned using desktop R 700 scanner. Intrusion was continued until 1-2mm positive overbite was achieved as clinically measured by a metal ruler graduated in mm.
Control group 1. The same procedures were performed in the same manner as in MOP group except for micro-osteoperforation step. Those procedures included impression taking for fabrication of intrusion splint, miniscrew implant placement with the same size, manner and sites, appliance assembly and force application. The same follow-up protocol was advocated as well.
Then records including CBCTs before and after intrusion were obtained to analyze difference in skeletal, dental, and soft tissue measurements between the groups. Digital models obtained at four weeks were analyzed and superimposed to determine the rate of intrusion and to detect the presence of any difference between the groups.
34 studies on the registry are indexed under Open Bite; 8 are open to participants now.
This study's enrollment of 30 is close to the median of 30 across 28 interventional studies indexed under Open Bite.
Browse Open Bite studies →Ain Shams University is the lead sponsor of 1,950 studies on the registry; 429 are open to participants now.
Of its 35 completed or terminated interventional studies of FDA-regulated products, 0 (0%) have results posted.
Compared within Open Bite, this study's primary condition as ClinicalTrials.gg classifies it; the registry's first condition term is Malocclusion. The counts are of registry records indexed under each term, refreshed daily. How we classify →
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Micro-osteoperforation was performed immediately before applying intrusion force on the maxillary posterior segment bilaterally using maxillary intrusion splint and miniscrew implants for anchorage
Procedure: Micro-osteoperforation
Posterior segment intrusion was performed bilaterally using the same intrusion splint and miniscrew implant anchorage set-up but without micro-osteoperforations
Device: Conventional posterior segment intrusion
Patients were subjected to micro-osteoperforations using Prope Excellerator MOP device. Three perforations were performed in a linear pattern at the buccal side, mesial and distal to the roots of maxillary posterior segment bilaterally immediately before intrusive force application.
Patients were treated with posterior segment intrusion using posterior acrylic splint. Miniscrew implants were placed bilaterally at the zygomatic buttress and palatal to maxillary first molar. Intrusion force was applied using closed coil springs from hooks at the splints to the heads of the implants for anchorage.
Rate of maxillary posterior segment intrusion (mm/4 weeks)
Measured on serial study models obtained every 4 weeks from baseline to achievement of 1-2 mm positive overbite. The rate of maxillary posterior segment intrusion was observed from follow up digital models through superimposition of successive models by Gom software and measuring the amount of intrusion for each tooth and every follow up visit to determine the rate of intrusion of each tooth per interval. A comparison was performed between the groups to determine the effect of MOPs on the rate of intrusion.
Time frame: Study models were obtained every four weeks from baseline until a positive overbite was obtained at an average of 6-9 months .
Skeletal, dentoalveolar and soft tissue changes
The evaluation of skeletal, dental and soft tissue changes before and after posterior segment intrusion in each group was performed by a customized three- dimensional analysis on Anatomage software. A comparison was performed between both groups to determine any changes in the pattern of intrusion.
Time frame: Patients were subjected to posterior segment intrusion forces until a positive overbite (+1-2 mm) was obtained at an average of 6-9 months
Evaluation of TMJ changes
Evaluation of positional and dimensional changes of the mandibular condyle was performed by certain measurement obtained at certain cross-sectional cuts on CBCTs obtained before and after posterior segment intrusion in both groups .
Time frame: From beginning of intrusion till a positive overbite was observed at an average of 6-9 months
Total amount of posterior intrusion (mm)
Three-dimensional linear change in vertical position of the maxillary posterior segment from baseline to end of intrusion, measured on CBCT using the palatal plane (ANS-PNS) as a stable reference plane. The distance from centroid of each tooth to that Palatal plane was measured before and after intrusion.
Time frame: From beginning of intrusion till a positive overbite was observed at an average of 6-9 months
Air way changes in volume after intrusion
Evaluate the pharyngeal airway space (PAS) volume in cm3 for patients with anterior open bite (AOB) before and after intrusion by using cone beam computed tomography (CBCT).
Time frame: From beginning of intrusion till a positive overbite was observed at an average of 6-9 months
Changes in alveolar bone density after posterior intrusion
Evaluation of alveolar bone density in Hounsfield Units (HU)ollowing intrusion using cross sectional cuts in pre- and post- intrusion CBCTs.
Time frame: From beginning of intrusion till a positive overbite was observed at an average of 6-9 months
Apical root resorption after intrusion (mm)
Evaluation of the development of apical root resorption in any root of the whole posterior segment bilaterally by measuring the difference in length of all roots before and after posterior segment intrusion using CBCTs scans. A comparison was made between both groups the evaluate the difference and the efficiency of micro-osteoperforation to reduce the risk of this problem. .
Time frame: From beginning of intrusion till a positive overbite was observed at an average of 6-9 months
Evaluation of the relationship between the amount of posterior intrusion and the subsequent crown lengthening requirements resulting from alveolar or soft tissue excess.
Correlation between the extent of posterior segment intrusion and the requirement for crown lengthening via alveolar bone or soft tissue reduction using CBCT obtained before and after intrusion.
Time frame: From beginning of intrusion till a positive overbite was observed at an average of 6-9 months
Air way changes in cross-sectional area after intrusion
Evaluate the pharyngeal airway space (PAS) narrowest cross-sectional areas in cm2 for patients with anterior open bite (AOB) before and after intrusion by using cone beam computed tomography (CBCT).
Time frame: From beginning of intrusion till a positive overbite was observed at an average of 6-9 months
Alveolar bone trabecular architecture changes
Evaluation of alveolar bone trabecular microstructural changes including buccal, palatal and apical alveolar bone in mm following intrusion using cross sectional cuts in pre- and post- intrusion CBCTs.
Time frame: From beginning of intrusion till a positive overbite was observed at an average of 6-9 months
Stability of posterior intrusion
Stability of posterior segment intrusion and open bite closure after using maxillary intrusion splint followed by conventional orthodontic treatment. Post brackets debonding CBCTs will be analyzed and compared by post-intrusion CBCT to determine the stability of treatment outcomes.
Time frame: Post-intrusion till finishing conventional orthodontic treatment an average of 2 years post intrusion
Root resorption after conventional orthodontic treatment
Evaluation of the development of apical root resorption in every molar and premolar in the whole posterior segment bilaterally after finishing the subsequent fixed orthodontic treatment and debonding of brackets. Post debonding CBCT was obtained to measure the length of the roots in mm in comparing them with those obtained before and immediately after intrusion.
Time frame: Post-intrusion till finishing conventional orthodontic treatment an average of 2 years post intrusion
Investigating the association between skeletal open bite malocclusion and maxillary constriction
Clinical examination of open bite cases as well as CBCT analysis to determine the correlation between skeletal open bite malocclusion and maxillary transverse deficiency.
Time frame: Three years during patients recruitment for the study
Association between open bite and other malocclusions in anteroposterior planes
Clinical and cephalometric examination for screeing open bite cases and determine the occurance of other malocclusion in anteroposterior planes
Time frame: During patients' recruitment for three years during the study
Correlation between open bite and enamel hypoplasia
Clinical assessment of enamel hypoplasia prevalence in patients with open bite malocclusion.
Time frame: During patients' recruitment for the study at an average of three years
Assessment of the effects of miniscrew placement in the maxillary zygomatic buttress on maxillary sinus health and integrity.
Evaluation of the risk of sinus perforation and penetration by zygomatic miniscrew and resulting changes in maxillary sinus health through comparison of baseline CBCTs before miniscrew implants insertion with post-intrusion CBCTs after zygomatic miniscrew implants insertion
Time frame: From beginning of intrusion till a positive overbite was observed at an average of 6-9 months
Miniscrew stability in zygomatic and palatal region
Miniscrew stability/failure rate (%): Number of zygomatic or palatal miniscrews requiring replacement or removal over total placement time of intrusion and stabilization of the case post-intrusion during fixed orthodontic treatment.
Time frame: From insertion till completion of intrusion at an average of 6-9 months, then after intrusion till debonding of brackets at an average of two more years.
Pulpal changes after intrusion of the whole posterior segment using intrusion splint
Pulpal sensitivity changes of maxillary molars and premolars : Cold test/electric pulp testing after intrusion and debonding.. •
Time frame: Long term follow-up after debonding 1 and 2 years follow up
Determining the rate of tooth movement using different software to analyze digital models
Comparison between measurements obtained after superimposition of successive digital models to measure the rate of intrusion using different softwares and different methods
Time frame: From beginning of intrusion till a positive overbite was observed at an average of 6-9 months
Ratio between posterior intrusion and anterior open bite closure
The correlation between the magnitude of posterior segment intrusion and the corresponding degree of mandibular autorotation and anterior open bite closure. This is measured through pre and post-intrusion CBCTs to determine the amount of molar and premolar intrusion and measure the corresponding mandibular auto-rotation in degrees and amount of anterior open-bite correction by measuring the vertical overlap between maxillary and mandibular incisors post-intrusion. •
Time frame: From beginning of intrusion till a positive overbite was observed at an average of 6-9 months
Investigation of alveolar bone morphological characteristics and thickness in skeletal open bite cases, with comparison among Class I, Class II, and Class III malocclusions.
Measurements of alveolar bone thickness or other parameters were made on CBCTs of open bite cases with different anteroposterior malocclusions and comparison was made between them. Alveolar bone thickness at the buccal and palatal sides for all anterior and posterior teeth in mm in open bite cases with different anteroposterior skeletal relationships. Also morphological differences in the mandible at different sites such as symphesis and condylar areas will be obtained in mm and compared between groups. Differences in bone density between groups will be evaluated in CBCTs using Hounsfield Units (HU)
Time frame: During period of patients recruitment within three years
Adverse effects of micro-osteoperforations (MOP)
Evaluation of adverse events related to MOP: Bleeding, swelling, infection, soft-tissue ulceration, root proximity/radiographic defects; recorded by occurrence and severity.
Time frame: Immediately after MOP and during follow up period (6-9 months)
Clinical periodontal problems developed after intrusion
Clinical assessment of periodontal condition including swelling, redness and development of pseudopockets after intrusion
Time frame: During intrusion at an average of 6-9 months
Plan to share: Yes
Supporting information: Study protocol
Time frame: No limit
Ran from Apr 2015 to primary completion in Dec 2022, 91 months.
Of 24 interventional studies with no phase under Open Bite, half reached primary completion within 17 months of starting (the median), counting those still running; a quarter within 10 and three quarters within 36. This study's 91 months is above that.
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