Clinical trial NCT06486324: Effects of Asymmetric Rapid Maxillary Expansion on Dentoskeletal Structures in Mixed Dentition
Official title: Investigation of the Effects of Rapid Maxillary Expansion With Locked Modified Acrylic Bonded Appliance on Dentofacial Structures in Mixed Dentition
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Maxillary Anomaly
Asymmetric Maxillary Arch (Disorder)
Cross Bite
Keywords: True unilateral posterior crossbite
Asymmetric maxillary expansion
Mixed dentition
Lead sponsor: TC Erciyes University
Sponsor class: OTHER
Collaborators: name: Selcuk University Scientific Research Projects Unit
First posted: 2024-07-03
Enrollment: 30
Sex: ALL
Minimum age (years): 7
Maximum age (years): 10
Standard ages: CHILD
Accepts healthy volunteers: yes
Allocation: NON_RANDOMIZED
Intervention model: SINGLE_GROUP
Intervention model description: Split-mouth model. The crossbite side of the patients was assigned as the treatment group, while the normal bite or non-crossbite side of the same patients was assigned as the positive control group.
Primary purpose: TREATMENT

Brief summary: The aim of this clinical trial was to determine the efficacy of a locked modified bonded acrylic rapid maxillary expansion appliance, also known as an asymmetric rapid maxillary expansion appliance (ARME), in patients with a true unilateral posterior crossbite resulting from transversal maxillary deficiency in the mixed dentition.

Detailed description: A posterior crossbite (PCB) is defined as an abnormal transverse or inverse relationship between the posterior teeth and dentition of the upper and lower jaws. A full buccal segment PCB involves multiple teeth in the posterior dentition and usually represents a transverse size discrepancy between the maxillary and mandibular relationships. This discrepancy is often caused by narrow or underdeveloped transverse dimensions of the maxillary halves. The underlying etiology of PCBs includes congenital, developmental, traumatic, or iatrogenic causes. Since spontaneous correction of this malocclusion is not possible even if the etiological factors are eliminated, it should be treated with maxillary expansion as early as possible.

The PCBs may be seen a unilateral posterior crossbite (UPCB) or bilateral posterior crossbite during all periods of dentition. A UPCB can be described as a functional UPCB or true UPCB. A functional UPCB is usually associated with a lateral shift of the mandible toward the crossbite side during the transition of the mandible. On the other hand, true UPCB is less common than functional UPCB and is caused by the narrowing of one of the maxillary halves. Increasing the maxillary arch transverse dimension is the main goal in the treatment of PCB. Although bilateral maxillary expansion is usually used to symmetrically widen the maxillary arch and eliminate mandibular shift as a standard treatment model in functional PCB, asymmetrical or unilateral maxillary expansion is recommended to expand narrowed sections of the maxillary halves and prevent overexpansion of the non-crossbite side in the treatment of true UPCB. Therefore, several removable or fixed maxillary expansion appliances that are slowly or rapidly activated were modified to produce differential effects on posterior teeth.

This clinical trial was designed to expand the upper jaw asymmetrically, i.e. to prevent the normal side of the bite from expanding while expanding the narrow part of the upper jaw. For this purpose, a locking mechanism was added to a bonded rapid maxillary expansion (RME) appliance to support the lower posterior teeth on the normal side of the bite.The hypothesis tested in the study was whether the true unilateral posterior cross-bite in the mixed dentition period could be corrected with a locked modified bonded rapid maxillary expansion appliance used for asymmetric expansion.

Children aged between 7 and 10 years old with true unilateral posterior crossbite were enrolled in the study. The efficacy of the appliance was compared between the crossbite and non-crossbite sides in the patients included in the study. The crossbite side of the patients was assigned as the treatment group, while the normal bite or noncrossbite side was assigned as the positive control group. Thus, two groups were formed for the study, and the trial was conducted on these groups.In other words, the study was planned as a self-controlled study. A negative control group could not be formed due to ethical reason. The reason for this is that the transversal problem may negatively affect both the anterioposterior and vertical development of the jaws in patients of this age during the developmental period, and therefore it was deemed necessary to correct the cross-bite problem as soon as possible after it was detected.Therefore, the purpose of this study was to evaluate specific dentoskeletal changes induced by treatment with true UPCB in mixed dentition with asymmetric RME.

Eligibility criteria: Inclusion Criteria:

* mixed dentition
* true unilateral posterior crossbite
* erupted first permanent molars and incisors
* all deciduous canines and molars or no more than one missing deciduous molar
* no history of orthodontic treatment
* no systemic disease
* no pathological periodontal status
* no excessive gagging reflex.

Exclusion Criteria:

* poor oral hygiene
* caries

Primary outcomes:
measure: Widths of skeletal structures
timeFrame: Before expansion (T1),through expansion completion,an average 1 month (T2),and through retention completion, an average 3 months (T3)
measure: Skeletal maxillomandibular width ratios
timeFrame: Before expansion(T1),through expansion completion an average 1 month(T2),and through retention completion an average 3 months(T3)
measure: Inclinations of upper and lower first molars
timeFrame: Before expansion(T1),through expansion completion an average 1 month(T2),and through retention completion an average 3 months(T3)
measure: Amount of movement of deciduous canines and first molars in the transversal plane on the crossbite and non-crossbite sides.
timeFrame: Before expansion(T1),through expansion completion an average 1 month(T2),and through retention completion an average 3 months(T3)
measure: Intercanine and intermolar distance on dental cast
timeFrame: Before expansion(T1),through expansion completion an average 1 month(T2),and through retention completion an average 3 months(T3)
Secondary outcomes:
measure: Position of the maxilla in the sagittal and vertical plane on lateral cephalometric radiography
timeFrame: Before expansion(T1),through expansion completion an average 1 month(T2),and through retention completion an average 3 months(T3)
measure: Position of the mandibula in the sagittal and vertical plane on lateral cephalometric radiograph
timeFrame: Before expansion(T1),through expansion completion an average 1 month(T2),and through retention completion an average 3 months(T3)
measure: Maxillomandibular relationship in the sagittal plane on lateral cephalometric radiograph
timeFrame: Before expansion(T1),through expansion completion an average 1 month(T2),and through retention completion an average 3 months(T3)
measure: Skeletal midface and lower face heights in vertical plane on lateral cephalometric radiograph
timeFrame: Before expansion(T1),through expansion completion an average 1 month(T2),and through retention completion an average 3 months(T3)
measure: Angulation and position of the upper central incisor on lateral cephalometric radiograph
timeFrame: Before expansion(T1),through expansion completion an average 1 month(T2),and through retention completion an average 3 months(T3)
measure: Angulation and position of the lower central incisor on lateral cephalometric radiograph
timeFrame: Before expansion(T1),through expansion completion an average 1 month(T2),and through retention completion an average 3 months(T3)
Other outcomes:
Locations:
Study officials:
affiliation: Selcuk University
name: Celal Irgın, Asst.Prof.
role: PRINCIPAL_INVESTIGATOR
References:
citation: Toroglu MS, Uzel E, Kayalioglu M, Uzel I. Asymmetric maxillary expansion (AMEX) appliance for treatment of true unilateral posterior crossbite. Am J Orthod Dentofacial Orthop. 2002 Aug;122(2):164-73. doi: 10.1067/mod.2002.125563.
citation: da Silva Filho OG, Boas MC, Capelozza Filho L. Rapid maxillary expansion in the primary and mixed dentitions: a cephalometric evaluation. Am J Orthod Dentofacial Orthop. 1991 Aug;100(2):171-9. doi: 10.1016/s0889-5406(05)81524-0.
citation: Sari Z, Uysal T, Usumez S, Basciftci FA. Rapid maxillary expansion. Is it better in the mixed or in the permanent dentition? Angle Orthod. 2003 Dec;73(6):654-61. doi: 10.1043/0003-3219(2003)0732.0.CO;2.