Systematic Review

By Dr. Gabriella Padalino , Dr. Emanuele Fantasia , Dr. Martina Maria D'Emidio , Dr. Elisa Lombardelli , Dr. Giuseppe Rodi
Corresponding Author Dr. Gabriella Padalino
Department of Oral and Maxillofacial Sciences, Sapienza University of Rome, viale ippocrate 146 - Italy 00161
Submitting Author Dr. Gabriella Padalino
Other Authors Dr. Emanuele Fantasia
Department of Oral and Maxillofacial Sciences, Sapienza University of Rome, - Italy

Dr. Martina Maria D'Emidio
Department of Oral and Maxillofacial Sciences, Sapienza University of Rome, - Italy

Dr. Elisa Lombardelli
Department of Oral and Maxillofacial Sciences, Sapienza University of Rome, - Italy

Dr. Giuseppe Rodi
Department of Oral and Maxillofacial Sciences, Sapienza University of Rome, - Italy


Class III malocclusion; Orthodontics; Functional appliances; Skeletal discrepancy

Padalino G, Fantasia E, D'Emidio M, Lombardelli E, Rodi G. Treatment options for Class III Malocclusions in growing patients: A Systematic Review. WebmedCentral ORTHODONTICS 2016;7(11):WMC005212

This is an open-access article distributed under the terms of the Creative Commons Attribution License(CC-BY), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Submitted on: 02 Nov 2016 07:46:35 PM GMT
Published on: 07 Nov 2016 01:25:43 PM GMT


The class III malocclusion is defined when the lower first molar is more mesial than the upper first molar and it can be determinated by maxillary retrusion, mandibular protrusion, or both.

The etiology is multifactorial, and it seems to be involved environmental and genetic factors. Indeed, class III malocclusion is the one most affected by genetic influences. Among these environmental factors considered responsible for its etiology there are: wrong postures, endocrine disturbances, congenital defects, trauma and nasoairway obstruction. An early treatment is required to reduce the need of treatment in the permanent dentition because if the malocclusion is diagnosed early, a lot of treatment modalities will be available. In contrast, in adulthood, the only treatment options are orthodontic or surgery camouflage.

The aim of this study is to analyze the current therapeutic strategies for the treatment of Class III malocclusion in growing patients. Facemask therapy, Frankel III and Bionator III are recommended for patients with maxillary deficiency. Facemask can be combined with palatal expansion because it would seem to facilitate the orthopedic effect of the facemask. The Frankel III stimulates mandibular growth through the muscle-blocking effects and stretching of the periosteum.

The chincup is used in growing patients with mandibular protrusion; the use determines clockwise rotation of the mandible and the retroinclination of mandibular incisors.

An important factor for treatment of Class III malocclusion is the origin of malocclusion. It’s very important to make an early diagnosis for choosing the most appropriate device.


In 1900,Angle described three types of dental malocclusions1. The dental class III malocclusion is defined when the first lower molar is more mesial than the upper first one. Therefore, the class III is defined as mesiocclusion situation.  Indeed, the skeletal class III malocclusion is a deviation in the sagittal plane of the relationship between maxilla and mandible, due to a deficiency and/or a backward position of the maxilla, or a prognathism and/or forward position of the mandible2,3,4. However, the classification of Angle is not able to explain the mechanisms underlying this phenomenon. In fact, the condition might be characterized by mandibular prognathism, maxillary retrognathism, retrusive mandibular dentition, protrusive maxillary dentition, and a combination of the above5.The actual classification is the following: prognathic mandible with a normally positioned maxilla; retrognathic maxilla with a normally positioned mandible; both maxilla and mandible normally positioned; retrognathic maxilla, prognathic mandible.

Until 1970 it was commonly believed that the classes III were caused solely by a jaw in the forward position82. However, it has been shown, that 30-40% of Class III are due to a development deficiency of the maxilla 6-12.

Different races show a different rate of prevalence of class III malocclusion. The prevalence rate was reported to be around 1–3% in the Caucasians; in the Latin populations is approximately 5%; a higher prevalence rate (15-23%) has been observed in Asian populations of Taiwanese, Japanese,

Korean and Chinese 13-30. The etiology of Class III malocclusion is multifactoral because it is due to the association of hereditary and environmental factors.

- hereditary factors: the class III malocclusion seems to be the one most affected by genetic influences. Numerous studies have shown a significantly higher incidence of this malocclusion between members of many generations31-34. An example of this inheritance is given by the European family of Habsburg; indeed, for 23 generations, some family members had a prominent jaw, to the point that the term “Habsburg jaw” has been coined to describe the prognathic mandible 35,36. However, the pattern of transmission is controversial; according to some authors, the transmission is autosomal recessive37; according to others, it is autosomal dominant with complete 38,39 or incomplete penetrance 15,40,41; yet, according to others follows a polygenic transmission mode 42.

- environmental factors: many environmental factors are held responsible for this malocclusion. The literature confirms the following:

  • wrong postures which cause the sliding forward of the mandible (e.i. nail biking)43,44;
  • endocrine disturbances such as gigantism or pituitary adenomas37,45-48;
  • congenital anatomic defects (e.i cleft lip, cleft palate)46,49;
  • trauma50,51;
  • nasoairway obstruction45,52.

The skeletal Class III malocclusion in growing patients is a complex problem of orthodontic practice. Early treatment is required to reduce the need of treatment in the permanent dentition, when the only available options are camouflage orthodontic treatment or surgery. Furthemore, early interventions can solve the little patient's facial looks, without upsetting the psychological aspects53. If the malocclusion is diagnosed in deciduous or mixed dentition, a lot of treatment modalities are available, including functional orthopedic appliances.  Furthermore, it is also important to identify whether the etiology is dental, functional, or skeletal. If the problem is skeletal, the cause might be an underdeveloped maxilla, an overdeveloped mandible, or a combination of both. If the cause is an underdeveloped maxilla, its growth can be stimulated through orthopedic force or a functional appliance. Instead, if the cause is an overdeveloped mandibole, the only alternative is surgery after growth. Various therapeutic modalities can be found in the literature regarding orthopedic treatment in Class III malocclusion 54-57. The aim of this study is to analyze the current therapeutic strategies in the treatment of Class III malocclusion in growing patients.

Materials and Methods

The prevalence of Class III malocclusion is a so important orthodontic topic that many articles have been published on international literature till now. The treatment of this type of malocclusion has represented a great challenge for all clinicians, for avoiding a final surgical treatment. So the systematic review of literature has been performed on the principal medical databases: PubMed (Medline), Embase and Scopus. The keywords used were: class III malocclusion, skeletal discrepancy, vitious Habits and functional appliances to identify all articles reporting on the topic of diagnosis and treatment of patients with single or multiple tooth agenesis till October 2016. No restrictions of time and languages have been fixed. The results have been filtered and valued following our eligibility criteria and then organized following the PRISMA method. The search identified 9,754 abstracts, which were reviewed manually and each article of interest was marked for further review. The full text of the marked studies was retrieved and studies that satisfied our eligibility criteria were included in this review. At the end only 43 full articles have been selected.


Treatment options

1) Facemask therapy: the use of facemask therapy is recommended for patients with maxillary deficiency. Maxillary protraction can be combined with palatal expansion because palatal expansion may destroy circummaxillary suture system, and presumably facilitates the orthopedic effects of the facemask4,44,58. Some authors reported the correction of class III malocclusions in only six months with early maxillary expansion and protraction59. When the maxilla moves forward and downward, the final effect is a posterior rotation of the the mandible60.

The most favorable period for initiation of therapy would appear to be the deciduous dentition. The earlier treatment produces a more effective result; however, the older children still have positive effects, so the orthopedic changes can be obtained until fourteen age.

Treatment in the deciduous dentition is able to produce a more significant anterior morphogenetic rotation of the mandible due to an upward-forward direction of condylar growth, leading to reduced mandibular protrusion and total lenght. Maxillary dento-alveolar protrusion induced by treatment is greater in subjects treated in later ages, whereas skeletal changes are more evident in children treated in the deciduous dentition.

The expansion of the palate advantages includes expansion of the maxilla with a posterior crossbite correction, increase arch length, the activation of circummaxillary sutures and a movement in forward and downward of the maxillary complex. Based on several studies, through the use of the face mask, there is an increases in SNA of about 2° and a reduction in SNB of about 1.7° 61,62,63.

Some authors59 reported correcting class III occlusione in six months with the use of facial mask and early maxillary expansion. At the end of treatment, the overcorrection is always recommended to stabilize the new position between two arches and to avoid recurrences. At the end of therapy, to maintain the posture of the orofacial muscles, it can be helpful to use a functional device such as Bionator or Frankel. Facemasks have various clinical applications. The orthodontist can choose between Petit or Delaire face mask as an extraoral part of the device with or without palatal expansion. The Delaire is the facial mask most used in clinical practice.

2) Frankel III: the treatment of Class III malocclusion for patients in the growth and development period usually is based on growth modification with a lot of functional appliances. In children with an underdeveloped maxilla, the FR III seems to redirect and stimulate mandibular growth through the muscle-blocking effects and stretching of the periosteum 54. The FR-3 appliance is based on the principle that resolution of maxillary retrusion may occur by using muscle forces 64.

The appliance is composed of four acrylic parts. There are two upper labial pads, that are positioned in the labial vestibule, with the aim of eliminate the pressure of the lip and stimulate the maxillary growth; them two vestibolar shields, positionated in the mandibular vestibule, remove the forces generated by masticatory muscles, determine the apposition of alveolar bone.

The device determines skeletal changes and dental changes.

àskeletal changes: the FR-3 stimulates the growth of the maxilla and restricts mandibular development by counteracting the forces of the surrounding muscles. Frankel declared the bone apposition at point A with the use of the FR III appliance, instead McNamara and Huge found that the device caused forward and downward movement of the maxilla.

Correction of Class III malocclusion through the use of the device, therefore, seems to take place by means the downward and backward rotation of the mandible caused by the appliance65,66.

àdental changes: the resolution of class III malocclusion also it occurs for linguoversion of the mandibular incisors, with a significant increase in overjet66-69. According to several studies, it is also a slight decrease in overbite, which seems to be due to the backward and downward rotation of the jaw66. The resolution of the skeletal class III malocclusion is also due, in part, to the downward and forward movement of the upper molars.

3) Chincup: the chincup can be used in growing patients with mandibular protrusion and with a normal maxilla70. The appliance can be used in deciduous or in mixed dentitions. If chincup has been used for a long time, several cases successfully treated have been described. The variables that can influence the success of the therapy are the duration of treatment, the age of the patient and the entity of applied forces.

Several studies have confirmed that patients treated with chincup show an improvement of the class III thanks to the clockwise rotation of the mandible, the increase in their anterior facial height and the retroinclination of mandibular incisors6,71-74. Also it occurs a signifivative reduction of the angle SNB, that can be caused by a brake on mandibular growth or an intense clockwise rotational effect6,73,75,76. In addition, several studies show an increase in the Wits index in patients treated with chincup, compared to those not treated.

The literature also supports the closure of the gonial angle70,72,73,75,77-81. This occurs because of the direction of force passing in the occipital region and in the glenoid fossa through and under the condyle, working as a fulcrum and causing the rotation of the ramus of the mandible.

Therefore, the orthopaedic results of chin-cup therapy may not only influence mandibular growth but they seem to induce posterior displacement of craniofacial structures. It was shown that the force directed backwards generated by the chincup, is transmitted to the condyle, with the risk of development of temporomandibular disorders (TMD) 82,83. In fact, the therapy would seem to determine the displacement of the condyle in the glenoid fossa with anterior dislocation of the articular disc, with the appearance of articular clicks.

4)Bionator III: This appliance is a modified device of the traditional Bionator. It can be used in the tratment of class III malocclusion in growing patients., The modified Bionator differs in various characteristics from the original Bionator. The labial arch is placed in the middle of the lower teeth; upper labial buttons and vestibular shields that deepen into upper fornix, in order to allow expansion of the maxillary arch; the lingual wire is in a different position to control the position of the tongue up to the upper first molar; the presence of an upper incisor inclined plane. The device should be worn for the whole day, about twenty-two hours.

The goal of the treatment of patients with skeletal class III is not just about the correction in the sagittal plane of the relation between the jaw, and the resolution of a decreased overjet. It must stabilize the occlusal relations at the end of the orthopedic or functional therapy with a long follow-up during the patient's adolescence and even in the early years of his adult life.


An important factor for treatment of Class III malocclusion in growing patient is the origin of malocclusion. Need to identify if the clinician is in the presence of a skeletal or dental class III and, in the cases of class III skeletal, if it is due to the mandibular prognathism or to the maxillary deficiency. So, it is very important to make an early diagnosis for choosing the most appropriate device.


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