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Academic Research Articles

View Academic Research Articles published by Dr German O. Ramirez-Yañez and other researchers.

Published by: Tancan Uysal; Ahmet Yagci; Sadik Kara and Sukru Okkesim

Influence of Pre-Orthodontic Trainer treatment on the perioral and masticatory muscles in patients with Class II division 1 malocclusion

The aim of this follow-up study was to evaluate the effects of Pre-Orthodontic Trainer (POT) appliance on the anterior temporal, mental, orbicularis oris, and masseter muscles through electromyography (EMG) evaluations in subjects with Class II division 1 malocclusion and incompetent lips. Present findings indicated that treatment with POT appliance showed a positive influence on the masticatory and perioral musculature.
Yagci_2011_EurJOrthod_January(1).pdf 402.73 KB

Published by: Gianluca M. Tartaglia; Gaia Grandi; Fabrizio Mian; Chiarella Sforza; Virgilio F. Ferrario

Non-invasive 3D facial analysis and surface electromyography during functional pre-orthodontic therapy: a preliminary report.

OBJECTIVES: Functional orthodontic devices can modify oral function thus permitting more adequate growth processes. The assessment of their effects should include both facial morphology and muscle function. This preliminary study investigated whether a preformed functional orthodontic device could induce variations in facial morphology and function along with correction of oral dysfunction in a group of orthodontic patients in the mixed and early permanent dentitions.
jappliedoralscience09_17_5.pdf 154.66 KB

Published by: Ahmet Yagci DDS, Tancan Uysal DDS PhD, Sadik Kara PhD and Sukru Okkesim PhD

The effects of myofunctional appliance treatment on the perioral and masticatory muscles in class I, division 1 patients.

This study aims to evaluate the effect of a myofunctional appliance - the pre-orthodontic trainer (POT) - on the perioral and masticatory muscles by electromyography (EMG) in individuals with an Angle Class II, Division 1 malocclusion.
Yagci_2010_WorldJOrthod_11_117-22c.pdf 1.18 MB

Published By: Dr Germàn O. Ramirez-Yañez

The Trainer System™ in the context of treating malocclusions
Functional Maxillary Orthopedics (FMO) is the subject in dentistry studying the treatment of malocclusions by stimulating or inhiiting the activity of the masticatory and/or facial muscles, as well as jaws development, and through that action, to stimulate modelling and remodeling of the maxillaries permitting a better tooth alignment. Thus, FMO produces a balance between the muscles of the creneo-mandibular system, followed by improving the relationship between the upper lower maxillaries, and as a consequence of that, teeth tend to position better. It is very important to understand the modus operandi of each of the FMO appliances that are available to treat malocclusions, because that permits the health professional to understand the philosophy behind each appliance and what may be the sucess and limitations that can be expected when treating each of them. The purpose of the present paper is to explain the modus operandi of the Trainers, a functional appliance designed to correct the wrong forces delivered by the muscles of the tongue, cheeks and lips, in doing so improving the position of the teeth.
Ortho_08_0909_Final_Myo_Part_1.pdf 74.70 KB
Ortho_1009_Final_Myo_Part_2.pdf 1.17 MB
Ortho_11&1209_Final_Myo_Part_3.pdf 541.89 KB

Published By: Akira KANAO, Masanori MASHIKO and Kosho KANAO

Application of functional orthodontic appliances to treatment of 'mandibular retrusion syndrome'Effective use of the TRAINER System™
This paper introduces the mechanics of the TRAINER System™ and clinical cases treated with the T4K™, demonstrating the effectiveness of the appliance in guiding the mandible forward and expanding the upper and lower arches in maxillary protrusion cases with “mandibular retrusion syndrome” often seen among Japanese. When we first saw the appliance, we wondered if such a simple appliance would have any effect. However, many “mandibular retrusion syndrome” cases have been treated successfully with the T4K™ in our clinic.

Published By: Dr John Flutter, BDS

The key to facial beauty and optimal patient health - two part series
We require five patterns to optimise healthy growth of the jaws and face which include the lips together at rest; teeth in or near contact; the tongue resting in the roof of the mouth; breathing through the nose; and no muscle movement around the mouth on the subconscious swallow. Research shows that much of the orthodontic treatment used to correct the position of the teeth will further lengthen the face. It is also known that lengthening the face will produce a less attractive face.
Flutter_part1Aug2009.pdf 364.87 KB
Flutter_part2_Aug2009.pdf 266.78 KB

Published By: Usumez, Uysal, Sari, Basciftci, Karaman, Guray

The Effects of Early Pre-Orthodontic TRAINER Treatment on Class II
The aim of this study was to clarify the dentoskeletal treatment effects induced by a Pre-Orthodontic TRAINER appliance treatment on Class II, division 1 cases. Twenty patients (10 girls and 10 boys, mean age 9.6 1.3 years) with a Class II, division 1 malocclusion were treated with Pre-Orthodontic TRAINER appliances (Myofunctional Research Co., Queensland, Australia). The patients were instructed to use the TRAINER every day for one hour and overnight while they slept. A control group of 20 patients (mean age 10.2 0.8 years) with untreated Class II, division 1 malocclusions was used to eliminate possible growth effects.
angleortho_2004_web.pdf 49.74 KB

Published By: C. Quadrelli, M. Gheorgiu, C. Marchetti, V. Ghiglione

Early myofunctional approach to skeletal Class II
Therapy aimed at skeletal Class II subjects is carried out at the Odontology Clinic of Milan University in accordance with studies conducted by Petrovic and Stutzmann (12, 13), with an initial orthopaedic phase focussing on condylar growth. Such a therapeutic phase is made to coincide with the peak of pre-pubertal growth, which we have identified by evaluating skeletal age by X-raying the wrist and hand, following the method according to Gianní (5). This is performed for the purpose of obtaining the greatest possible growth period, coupled to an acceptable duration of therapy.
mondoortodontico_2002_web.pdf 872.29 KB

Published By: Germàn O. Ramirez-Yañez

Early Treatment of a Class II,Division 2 Malocclusion with the TRAINER for Kids (T4K™): A Case Report
This paper reports a Class II, division 2 malocclusion case successfully treated at an early age and in a relatively short period of time using the Trainer for Kids (T4K), a prefabricated functional appliance. Skeletal changes observed in the before and after treatment cephalic radiographs were compared with the expected changes produced by the patient’s natural growth. The functional appliance’s effects resulting in the outcomes observed in this clinical case, as well as the importance of identifying the etiological factors when treating a malocclusion will be discussed.
Ramirez-Yañez_2008_JCPD_32_325-30.pdf 231.98 KB
Combining Functional and Fixed Appliances to Improve Results in Open Bite Treatment
Open bite is one of the most challenging malocclusions and its treatment must aim to improve occlusion and muscular function in the masticatory system, producing a satisfactory and stable result. This clinical report presents a patient with an open bite in mixed dentition associated with a Class II, division 1 malocclusion and a posterior unilateral crossbite. By combining functional and fixed appliances, the open bite was closed, a good occlusion was reinstated and muscular activity was improved in a simpler way. Therefore, this case report supports the idea of including myofunctional treatment when an open bite is treated at an early age.
Ramirez-Yanez_2007_Funct_Orthod.pdf 551.97 KB
Dimensional Changes in Dental Arches After Treatment with a Prefabricated Functional Appliance
The purpose of this study was to determine the effect of the T4K, a prefabricated functional appliance, on the transverse and anterior-height dimensions of the maxillary and mandibular dental arches. Dimensions before and after treatment were measured on the sample, then, natural growth was subtracted from the treatment effects and compared with twice the error of the method. A clinically significant increase of both dimensions was observed in the maxilla and mandible when Class II malocclusion patients were treated with the T4K. Therefore, this retrospective study demonstrates that T4K is a valid treatment choice at an early age when transverse expansion is part of the treatment goal.
Ramirez-Yanez_2007_JCPD_31_279-83.pdf 202.82 KB
Insights into Orthodontic Treatment
Almost a century was necessary to find some new alternatives for orthodontic treatment. Since the introduction of brackets, the most significant change in orthodontic industry has been moving from weld brackets to resin bonded brackets and some improvements in wires features. However, the philosophy of treatment did not change as the only purpose of treatment was to move teeth and to expect that the whole oral system might adapt to the performed changes.
Ramirez-Yanez_2006_Dental_Asia_July_August_15-16.pdf 58.40 KB
Dental Arches Expansion with Ortho-System
Maxillary and mandibular expansion has been proposed to increase the arch perimeter and to avoid extractions during orthodontic treatment. This paper describes a novel method to produce expansion of the dental arches, and at the same time, to treat muscular dysfunctions which may be the etiological factor of the malocclusion. Two cases treated with the Ortho-System are described and the advantage of this method of treatment is discussed.
Ramirez-Yanez_2006_Dental_Asia_36-40.pdf 223.14 KB
Soft Tissue Dysfunction: a Missing Clue when Treating Malocclusions
Contemporaneous treatment of malocclusions concerns about the effect of the muscular activity in the occlusion. Treatment of malocclusion involves dental alignment, jaw repositioning, stabilization of the activity of the masticatory muscles, the muscles of the tongue and the muscles of the cheeks and lips in order to achieve a balance between the forces delivered on the arches and teeth by all the muscles involved in oral functions.
Ramirez-Yanez_2005_RevIntOrtopFunc_1_483-94.pdf 755.96 KB
Influence of growth hormone on the craniofacial complex of transgenic mice.
Growth hormone (GH) secretion affects bone and cartilage physiology. This study investigated the effect of GH on the size of the craniofacial structures and their angular relationship.
Ramirez_2005_EurJOrthod.pdf 197.54 KB
Periodontal treatment needs in a native island community in Colombia determined with CPITN.
Aims: To identify the prevalence and different degrees of periodontal disease in an isolated community (Isla Grande, Colombia) with no dental services and low educational level with the use of CPITN, and to establish periodontal treatment needs in different age groups.
Orozco_2004_IDJ_54.pdf 77.83 KB
Incisor disocclusion in rats affects mandibular condylar cartilage at the cellular level.
The effect of altered occlusion on the mandibular condylar cartilage remains unclear.
Ramirez_2004_ArchOralBiol_49_393-400.pdf 287.38 KB
Influence of growth hormone on the mandibular condylar cartilage of rats.
Growth hormone (GH) stimulates mandibular growth but its effect on the mandibular condylar cartilage is not well understood.
Ramirez_2004_ArchOralBiol_49_585-90.pdf 163.45 KB
The Mandibular Condylar Cartilage: a Review.
The condylar cartilage is the most important growing site in the mandible1,2,3. This does not deny that other areas play an important role in mandibular growth, and influence the amount and direction of that growth. However, the condylar cartilage is responsible for the final length of the mandible2. The purpose of this paper is to review the actual knowledge about the physiology of the mandibular condylar cartilage and how this cartilage responds to extrinsic and intrinsic stimulus.
Ramirez_2004_RevIntOrtopFunc_1_85-94.pdf 145.83 KB
Growth Hormone and Epidermal Growth Factor in Salivary Glands of Giant and Dwarf Transgenic Mice.
Epidermal growth factor (EGF) in rat salivary glands is regulated by testosterone, thyroxin, and growth hormone (GH).
Young_2004_JHistochemCytochem_52_1191-7.pdf 351.86 KB
Planas Direct Tracks for Early Crossbite Correction.
This article describes the use of composite inclined planes called Planas Direct Tracks (PDTs) to correct more complex cases of crossbite in the deciduous dentition.
Ramirez_2003_JCO_37_294-298.pdf 298.26 KB
Condylar Fracture: Nontreatment Case Followed Over 23 Years
This article describes a case of early mandibular condylar fracture in a female patient. Follow-up visits over about 23 years without treatment showed completely re-stabilized anatomy and function after the pubertal growth spurt. Temporary ankylosis and lack of growth with severe deviation and facial asymmetry had been initially observed. The management philosophy of pediatric condylar fractures is discussed and a conservative approach is suggested for such cases. World J Orthod 2002;3:349–352.
Ramirez-Yanez_2002_WJO_3_349-52.pdf 90.76 KB
To view other studies in Spanish CLICK HERE
To view other studies in Portuguese CLICK HERE

Research References - This link provides research references on articles related to tongue position and function, mode of breathing and the effects they have on poor facial growth and malocclusion.