Effects of maxillary molar intrusion with zygomatic anchorage on the stomatognathic system in anterior open bite patients

An anterior open bite is one of the most difficult malocclusions in orthodontic treatment. For such malocclusion, orthodontic miniscrew insertion into both buccal and palatal alveolar regions has been indicated for molar intrusion, but it involves a risk of tooth root injury. To solve the problem, a midpalatal miniscrew-attached extension arm (MMEA) is adopted. However, this method causes palatal tipping of the molar because intrusive loads were applied only from the palatal side. Currently, a transpalatal arch is added to avoi0d tipping movement, but it induces the patient’s discomfort. Hence, the objective of this study was to evaluate the loading conditions for maxillary molar intrusion without tipping movement, only by MMEA through finite element (FE) analysis. FE models of maxillary right first molar and surrounding tissues were created. Three hook positions of MMEA were set at 6.0 mm perpendicular intervals in the occluso-apical direction along the mucosal contour. An intrusive unit load was applied from the palatal side of the molar, and various counter loads were applied from the buccal side. An optimal counter load for molar intrusion without palatal tipping was observed in each hook position. In conclusion, an ideal maxillary molar intrusion can be achieved only by MMEA with an optimal counter load.

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Prediction of mandibular movement and its center of rotation for nonsurgical correction of anterior open bite via maxillary molar intrusion

The Angle Orthodontist ◽

10.2319/102317-714.1 ◽

2018 ◽

Vol 88 (5) ◽

pp. 538-544 ◽

Cited By ~ 6

Author(s):

Kyunam Kim ◽

Kwangchul Choy ◽

Young-Chel Park ◽

Seo Yeon Han ◽

Heekyu Jung ◽

...

Keyword(s):

Linear Regression Analysis ◽

Open Bite ◽

Reference Plane ◽

Mandibular Movement ◽

Anterior Open Bite ◽

Counterclockwise Rotation ◽

Molar Intrusion ◽

Lateral Cephalograms ◽

Maxillary Molar ◽

The Relationship

ABSTRACT Objectives: To evaluate quantitatively the relationship between molar intrusion (change [Δ] maxillary first molar [U6]–palatal plane [PP]) and changes in vertical and sagittal cephalometric parameters and to determine the center of mandibular autorotation. Materials and Methods: Twenty-one patients diagnosed with anterior open bite and successfully treated with molar intrusion (overbite [OB] > 0 mm) were retrospectively enrolled. Lateral cephalograms taken before and after molar intrusion were used to measure changes in vertical and sagittal cephalometric parameters. The center of mandibular autorotation was calculated by measuring displacement of gonion (Go) and pogonion (Pog). Paired t-tests were used to compare variables, and linear regression analysis was used to examine the relationship between ΔU6-PP and other variables. Results: The mandible exhibited counterclockwise rotation after maxillary molar intrusion, which led to closure of anterior open bite. Strong linear relationships, in descending order, between ΔU6-PP and ΔOB, Δanterior facial height (AFH), Δvertical reference plane (Pog), and Δsella-nasion to Go-menton (SN-GoMe), were observed. When the maxillary molar was intruded 1 mm, OB increased by 2.6 mm, AFH decreased by 1.7 mm, Pog moved forward by 2.3 mm, and SN-GoMe decreased by 2°. The center of mandibular autorotation was located 7.4 mm behind and 16.9 mm below condylion after molar intrusion. Conclusions: The mandible exhibited counterclockwise rotation after maxillary molar intrusion; the center of mandibular autorotation was located behind and below condylion with individual variations.

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Dentoskeletal changes following mini-implant molar intrusion in anterior open bite patients

The Angle Orthodontist ◽

10.2319/090514-625.1 ◽

2015 ◽

Vol 85 (6) ◽

pp. 941-948 ◽

Cited By ~ 23

Author(s):

Tyler R. Hart ◽

Richard R. J. Cousley ◽

Leonard S. Fishman ◽

Ross H. Tallents

Keyword(s):

Observation Time ◽

Open Bite ◽

Occlusal Plane ◽

Plane Angle ◽

Anterior Open Bite ◽

Mini Implants ◽

Molar Intrusion ◽

Adolescent Patients ◽

Maxillary Molar ◽

Cephalometric Study

ABSTRACT Objective: To evaluate skeletal and dental changes after intrusion of the maxillary molars in subjects with anterior open bite. Materials and Methods: This retrospective cephalometric study evaluated skeletal and dental changes resulting from the use of maxillary orthodontic mini-implants in 31 consecutively treated patients. Radiographs were taken at the start and end of maxillary molar intrusion to evaluate the associated changes. Statistical analysis was performed using a one-sample t-test. Results: The mean treatment observation time was 1.31 years (SD = 2.03). The maxillary first molars (P = 0.0026) and second molars (P = 0.039) were intruded. However, the mandibular first molars (P = 0.0004) and second molars (P = 0.003) erupted in adolescent patients. Both the maxillary and mandibular first molars inclined distally (P = 0.025 and P = 0.044, respectively). The mandibular plane angle decreased (P = 0.036), lower facial height decreased (P = 0.002), and the occlusal plane angle increased (P = 0.009). The overbite increased (P < .0001). The ANB angle decreased (P < .0001). Mandibular dental and skeletal changes were more apparent in adolescents, while adults tended toward maxillary changes. Conclusions: Vertical traction from orthodontic mini-implants reduces the maxillary posterior dentoalveolar height, thereby assisting orthodontic closure of anterior open bite. However, simultaneous eruption or extrusion of the mandibular molars should be controlled. Adolescent patients tend to demonstrate more favorable effects of mandibular autorotation than do adults.

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Mandibular Prognathism and Anterior Open Bite: Treatment by Orthodontic Molar Intrusion and Two-jaw Surgery

Asian Journal of Oral and Maxillofacial Surgery ◽

10.1016/s0915-6992(06)80047-6 ◽

2006 ◽

Vol 18 (4) ◽

pp. 296-302

Author(s):

Hiromi Yoshitake ◽

Eri Oki ◽

Kazuhiro Ichikawa ◽

Takatoshi Itoh ◽

Takami Itoh ◽

...

Keyword(s):

Open Bite ◽

Anterior Open Bite ◽

Mandibular Prognathism ◽

Molar Intrusion ◽

Jaw Surgery

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A prospective clinical trial of the effects produced by the extrusion arch in the treatment of anterior open bite

Progress in Orthodontics ◽

10.1186/s40510-020-00339-z ◽

2020 ◽

Vol 21 (1) ◽

Author(s):

Juliana de Brito Vasconcelos ◽

Renata Rodrigues de Almeida-Pedrin ◽

Thais Maria Freire Fernandes Poleti ◽

Paula Oltramari ◽

Ana Cláudia Ferreira de Castro Conti ◽

...

Keyword(s):

Open Bite ◽

Mixed Dentition ◽

Anterior Open Bite ◽

Significance Level ◽

Lateral Cephalograms ◽

Maxillary Molar ◽

Facial Pattern ◽

Dental Models ◽

Maxillary Incisors ◽

Maxillary Dentition

Abstract Aim To evaluate the maxillary dentition effects of the extrusion arch for anterior open bite (AOB) correction in mixed dentition patients. Materials and methods Fourteen subjects with an initial mean age of 9.17 ± 1.03 years presenting with dentoalveolar AOB (mean − 1.28 ± 1.46 mm) and normal facial pattern (FMA = 25.76°) were treated with an extrusion arch. The mean treatment period was 7.79 ± 2.58 months. Lateral cephalograms and dental models were taken before (T0) and after the correction of AOB (T1). Data were analyzed using paired t test to evaluate differences between T0 and T1. For all tests, a significance level of P < .05 was used. Results All patients achieved positive overbite at T1, with a mean increase of 3.07 mm. The maxillary incisors extruded 1.94 mm. Retroclination of the maxillary incisors (− 6.15°) and an increase in the interincisal angle (5.57°) were observed. There was a significant decrease in the distance between the incisal edge of the maxillary incisors and the molars (− 2.21 mm). There was significant mesial tipping of the maxillary molar (− 11.49°). Significant reductions of overjet (− 1.65 mm), arch perimeter (− 3.02 mm), and arch length (− 2.23 mm) were noted. The transverse maxillary intermolar distance did not change significantly. Conclusions The use of a maxillary extrusion arch was effective in the treatment of AOB. Overbite increased due to incisor extrusion, as well as retroinclination and overjet reduction. However, side effects, such as mesial molar tipping and decreases in arch perimeter and length might occur.

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Treatment of adult patient with hyperdivergent retrognathic phenotype and anterior open bite: report of a case with non-surgical orthodontic approach

Dental Press Journal of Orthodontics ◽

10.1590/2177-6709.25.4.075-084.bbo ◽

2020 ◽

Vol 25 (4) ◽

pp. 75-84

Author(s):

Marinho Del Santo Jr

Keyword(s):

Young Adult ◽

Adult Patient ◽

Orthognathic Surgery ◽

Clinical Case ◽

Open Bite ◽

Therapeutic Result ◽

Anterior Open Bite ◽

Young Adult Patient ◽

Molar Intrusion

ABSTRACT Adult patients with anterior open bite and hyperdivergent retrognathic phenotype demand complex treatments, as premolar extractions, molar intrusion or orthognathic surgery. In the present clinical case, a young adult patient without significant growth, with Class I and anterior open bite, was treated with four premolar extractions. The therapeutic result shows good intercuspation, good facial esthetic, good function balance, and stability in a two-year post-fixed treatment follow-up.

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Molar Intrusion using TADs in the Management of an Anterior Open Bite: A Case Report

Dental Update ◽

10.12968/denu.2021.48.3.193 ◽

2021 ◽

Vol 48 (3) ◽

pp. 193-199

Author(s):

Ariane Sampson ◽

Ali Payam Sattarzadeh

Keyword(s):

Orthodontic Treatment ◽

Open Bite ◽

Orthodontic Appliances ◽

Anterior Open Bite ◽

Temporary Anchorage Devices ◽

Molar Intrusion ◽

Fixed Orthodontic Appliances ◽

Skeletal Change ◽

Non Surgical Treatment ◽

Risk Of Relapse

The prevalence of an anterior open bite ranges in the literature from 1.5% to 11%, with great racial variance. Stable non-surgical treatment of an anterior open bite is notoriously unpredictable, with a high risk of relapse and an uncertainty of true skeletal change. Temporary anchorage devices (TADs) are increasingly used to enhance and simplify orthodontic biomechanics, enabling clinicians to push the boundaries of orthodontic treatment. In anterior open bite cases, TADs may be used predictably for molar intrusion and improvement of the overbite. We describe a 16-year-old male with a Class I incisal relationship on a skeletal I base and increased vertical proportions, complicated by a 4-mm anterior open bite secondary to a previous digit sucking habit. Treatment involved fixed orthodontic appliances on an extraction basis, and molar intrusion using TADs. TADs provide a safe and effective alternative to reducing an anterior bite in a patient whose growth is complete. CPD/Clinical Relevance: Understanding the options for the treatment of an anterior open bite and the limits of orthodontic camouflage will help clinicians provide their patients with the necessary information with which to make informed decisions.

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Effect of molar intrusion with temporary anchorage devices in patients with anterior open bite: a systematic review

Progress in Orthodontics ◽

10.1186/s40510-016-0122-4 ◽

2016 ◽

Vol 17 (1) ◽

Cited By ~ 23

Author(s):

Ahmad Saleem Alsafadi ◽

Mohannad M. Alabdullah ◽

Humam Saltaji ◽

Anas Abdo ◽

Mohamed Youssef

Keyword(s):

Systematic Review ◽

Open Bite ◽

Anterior Open Bite ◽

Temporary Anchorage Devices ◽

Molar Intrusion

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Nonsurgical treatment of skeletal anterior open bite in adult patients: Posterior build-ups

The Angle Orthodontist ◽

10.2319/030316-188.1 ◽

2016 ◽

Vol 87 (1) ◽

pp. 33-40 ◽

Cited By ~ 7

Author(s):

Arturo Vela-Hernández ◽

Rocio López-García ◽

Verónica García-Sanz ◽

Vanessa Paredes-Gallardo ◽

Felicidad Lasagabaster-Latorre

Keyword(s):

Open Bite ◽

Anterior Open Bite ◽

Retention Period ◽

Term Stability ◽

Long Term Stability ◽

Skeletal Changes ◽

Molar Intrusion ◽

Mandibular Plane ◽

Lateral Cephalograms

ABSTRACT Objective: To (1) evaluate the efficacy of build-ups in the correction of anterior open bite in adults, (2) evaluate their efficacy in producing molar intrusion, (3) analyze skeletal and dental changes, and (4) assess the long-term stability. Materials and Methods: The sample consisted of 93 lateral cephalograms from 31 patients with skeletal and dental anterior open bite. The patients had received orthodontic treatment consisting of bonded resin blocks on the maxillary molars combined with Tip-Edge Plus bracket appliances. Cephalometric measurements were performed on radiographs taken before treatment (T1), after treatment (T2), and after a retention period (T3), which were analyzed and compared. Results: Significant dental and skeletal changes were observed after treatment. Molar intrusion averaging 1 mm; 1.44 and 1.57 mm extrusion of mandibular and maxillary incisors, respectively; and a mean of 3.98 mm overbite increase were observed. The mandibular plane angle showed a mean closure of 1.19°, and there was a mean decrease in anterior facial height of 0.7 mm. A mild relapse tendency was observed, but long-term stability was acceptable. Conclusions: Build-ups are an effective treatment alternative for anterior open bite in adults. Outcomes remain significantly stable during the retention period.

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Outcomes and Stability of Anterior Open Bite Treatment with Skeletal Anchorage in Non-Growing Patients and Adults Compared to the Results of Orthognathic Surgery Procedures: A Systematic Review

Journal of Clinical Medicine ◽

10.3390/jcm10235682 ◽

2021 ◽

Vol 10 (23) ◽

pp. 5682

Author(s):

Piotr Malara ◽

Susanne Bierbaum ◽

Beata Malara

Keyword(s):

Systematic Review ◽

Orthognathic Surgery ◽

Data Extraction ◽

Open Bite ◽

Long Term Results ◽

Published Data ◽

Skeletal Anchorage ◽

Anterior Open Bite ◽

Molar Intrusion ◽

Molar Teeth

The objective of this review is to evaluate, on the basis of the available literature, if anterior open bite (AOB) can be successfully treated with the intrusion of molar teeth using skeletal anchorage in non-growing patients and adults and if this treatment modality provides comparable results to those obtained by orthognathic surgery procedures. Methods: A systematic review of published data in major databases from 2000 to 2021 was performed. Results: In total, 92 articles were included in title and abstract screening, and only 16 articles (11 concerning AOB correction by molar intrusion with skeletal anchorage, and five considering AOB treatment by orthognathic surgical intervention) qualified for thorough data extraction and analysis. Conclusions: On the basis of this review, it seems to be possible to obtain successful results for AOB treatment in non-growing patients and adults by means of the intrusion of molar teeth with skeletal anchorage. However, due to the different methods of assessing treatment outcomes used by different authors, it is not possible to state conclusively whether the treatment of AOB by means of molar intrusion with skeletal anchorage provides long-term results that are comparable to orthognathic surgery procedures.

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