|Year : 2020 | Volume
| Issue : 2 | Page : 78-86
Rapid maxillary expansion facemask therapy in growing patients: A 2 case report and review of literature
Tanzin Palkit1, Isha Aggarwal1, Mandeep Kaur Bhullar1, Merry Goyal1, Neetika Singh1, Vinit Kumar Singh2
1 Department of Orthodontics and Dentofacial Orthopedics, Bhojia Dental College and Hospital, Baddi, Himachal Pradesh, India
2 Department of Orthodontics and Dentofacial Orthopedics, Vananchal Dental College and Hospital, Garhwa, Jharkhand, India
|Date of Submission||30-Jul-2020|
|Date of Acceptance||04-Sep-2020|
|Date of Web Publication||31-Oct-2020|
Dr. Tanzin Palkit
Department of Orthodontics and Dentofacial Orthopedics, Bhojia Dental College and Hospital, Baddi, Himachal Pradesh
Source of Support: None, Conflict of Interest: None
Class III malocclusion is progressive in nature and it worsens with age. Class III malocclusion is associated with any deviation in the sagittal relationship of the maxilla and the mandible; it is characterized by a deficient maxilla, retrognathic mandible, or a combination of both. It is very difficult to diagnose and treat Class III malocclusion. Many treatment approaches can be found in the literature regarding orthopedic and orthodontic treatment of Class III malocclusion, including intra- and extra-oral appliances. The early treatment of Class III malocclusions requires orthopedic intervention at the end of primary dentition or the beginning of mixed dentition, prior to growth spurt, which provides successful results, with good facial balance, modifying the maxillofacial growth and development, and prevents future surgical treatment by increasing the stability. Approximately 30%–40% of Class III patients exhibit some degree of maxillary deficiency; therefore, devices can be used for maxillary protraction for orthodontic treatment in early mixed dentition. In cases in which dental components are primarily responsible for Class III malocclusion, early therapeutic intervention is recommended. In this article, we described the treatment options for Class III malocclusion in growing patient with an emphasis on maxillary protraction.
Keywords: Class III malocclusion, face mask, rapid maxillary expansion
|How to cite this article:|
Palkit T, Aggarwal I, Bhullar MK, Goyal M, Singh N, Singh VK. Rapid maxillary expansion facemask therapy in growing patients: A 2 case report and review of literature. Indian J Oral Health Res 2020;6:78-86
|How to cite this URL:|
Palkit T, Aggarwal I, Bhullar MK, Goyal M, Singh N, Singh VK. Rapid maxillary expansion facemask therapy in growing patients: A 2 case report and review of literature. Indian J Oral Health Res [serial online] 2020 [cited 2021 Apr 16];6:78-86. Available from: https://www.ijohr.org/text.asp?2020/6/2/78/299703
| Introduction|| |
Class III malocclusions have attracted more attention than other problems in orthodontics for centuries. Even in Renaissance portraits and paintings, Class III malocclusions appear to be a significant feature. Today, patients are even more aware of the apparent effects on the external appearance, and therefore, even less frequent than other malocclusions, due to their adverse effects on the psychosocial status of the patients. Etiologic factors for Class III malocclusions include a wide spectrum of skeletal and dental compensation components. The condition might be characterized by mandibular prognathism, maxillary retrognathism, retrusive mandibular dentition, protrusive maxillary dentition, and a combination of the above. Ellis and McNamara found that 65%–67% of all Class III malocclusions were characterized by maxillary retrognathism. The worsening of Class III malocclusion increases with age. A good facial balance can be obtained by modifying the maxillofacial growth and development with an early orthodontic intervention. Many treatment approaches can be found regarding orthopedic and orthodontic treatment of Class III malocclusion. These include intra- and extra-oral appliances such as a facemask, functional regulator, removable mandibular retractors, splints, Class III elastics, chin cup, and mandibular cervical headgear. The decision-making process for treating these malocclusions is characterized by the choice between orthopedic treatment of the malocclusion in growing patients or delayed intervention in terms of corrective jaw surgery at the end of the active growth period Baccetti et al., 2002. The early orthopedic treatment of Class III malocclusions, at the beginning of mixed dentition, prior to growth spurt, provides facial balance, modifies the maxillofacial growth and development, and prevents a future surgical treatment by increasing the stability. The early Class III treatment has advantages such as it allows the eruption of canines and premolars in normal relation, eliminates the traumatic occlusion of incisors, which might lead to gingival recession, provides maxillary growth and improves the self-esteem of the child. In recent years, maxillary protraction treatment with and without rapid maxillary expansion (RME) has become a common technique for correcting maxillary retrusion. The popularity of facemask therapy has increased due to an awareness of maxillary deficiency as a component of the Class III structural etiology.,, Furthermore, maxillary expansion has been advocated as an important part of facemask protraction because it reportedly disrupts the circum maxillary sutural system and therefore facilitates the orthopedic effect attempted by face mask therapy.,,, Additional benefits have been reported using RME in conjunction with maxillary protraction in treating hypoplastic maxillary Class III patients. These include transverse expansion to correct posterior crossbites, splinting of the maxillary dentition against forward movement and anterior constriction during protraction therapy, in addition to backward and downward rotation of the mandible which softens the Class III. Disarticulation of the circummaxillary sutures is postulated to assist in the production of the orthopedic effects.,,, Although maxillary expander-facemask appliances achieve excellent orthopedic effects, they demand special patient compliance and are not as esthetic or comfortable due to their physical appearance and discomfort from the anchorage pads. The major problem with extraoral anchorage is of patient compliance, due to the appearance of the extraoral appliance. Considering this problem, Chun et al. in 1999, introduced the tandem traction bow appliance for the treatment of growing Class III patients. Klempner did some modifications in the appliance later on. Treatment results with RME/facemask therapy actually comprise a combination of forward movement of the maxilla, clockwise, and backward rotation of the mandible and forward movement of the upper incisors with retrusion of the lower ones. Kapust et al.,(1998) and Saadia and Torres(2000) reported that facemask/expansion therapy may be most effective in early treatment at a very young age. Other authors underlined that the outcome of orthodontic treatment of skeletal Class III has favorable effects when it is started before the puberal growth spurt (Baccetti et al., 2004; Ngan et al., 1997). The majority of patients who receive an orthopedic treatment has positive overjet after treatment and maintain this result also after postpubertal skeletal maturation. Overcorrecting Class III with functional appliances is advisable (Baccetti et al., 2004; Farronato et al., 2007).
Aim and objectives
These two case reports present RME with facemask therapy used for maxillary protraction to achieve clinically desirable results without relying much on patient co-operation in young growing patients.
| Case Report 1|| |
A 10-year-old boy reported to the Department of Orthodontics and Dentofacial Orthopedics with a chief complaint of forwardly placed lower jaw. On extraoral examination, he had a concave facial profile with retrognathic maxilla, obtuse nasolabial angle, protrusive mandible, and incompetent lips. Intraorally, he had Angle's Class I malocclusion, Class III canine relation on both sides, anterior crossbite, and a reverse overjet [Figure 1]. The panoramic radiograph showed no missing teeth or pathologies. Cephalometric analysis indicated a skeletal Class III jaw bases due to posteriorly positioned maxilla along with a horizontal growth pattern with proclined lower incisors and upper incisor inclination [Figure 2].
- Correction of skeletal Class III
- Correction of reverse overjet
- Obtaining Class I canine relationship
- Correction of anterior crossbite
- Achieving a pleasant soft tissue profile.
Early phase (phase I) of orthopedic treatment was planned to induce harmonious skeletal growth and improve facial esthetics. It was started with RME followed by facemask therapy for sagittal maxillary advancement, correct skeletal Class III malocclusion. Fixed orthodontic mechanotherapy (phase II) was done later by extracting upper 1st premolars and lower 2nd premolars for the final detailing of occlusion.
In the phase I of the treatment was RME till the circummaxillary sutures, sagittal correction was not needed because there is no posterior crossbite. The upper assembly comprised of an acrylic plate with a HYRAX embedded in it [Figure 3]. The HYRAX was activated for 14 days with two turns in a day, i.e., 180° in morning and one in evening. After 14 days, the screw was locked and the facemask therapy was started for maxillary protraction [Figure 4]. The facemask was used for another 6 months, for first 2 weeks 8 Oz elastics were used and after that for next 2 and a half months 14 Oz elastics were used. Facemask was used as retainer for the next 3 months. Six months after completion of phase 1 of the treatment, the RME and the facemask were removed and a retention plate with jackscrew was placed to prevent the relapse. In phase 2 of treatment fixed mechanotherapy was done with extraction of 1st premolars in upper arch to relieve crowding and 2nd premolars in lower arch to maintain the molar relation.
The patient was assessed after phase 1 of treatment with hyrax and facemask therapy. Progress showed favorable growth between the maxilla and the mandible and anterior crossbite correction [Figure 5]. Post protraction cephalometric tracings [Figure 6] revealed forward movement of maxilla and counterclockwise tipping of the palatal plane. The ANB angle changed from–8° to 1°. FMA opened from 26° to 27°. Slight labial tipping of the maxillary incisors was also observed. The point A also shifted anteriorly by 6 mm approximately. In Phase 2 of the treatment initial leveling and alignment was done with 0.012” Niti, 0.014” Niti, 0.016” Niti, 0.017 0.025” SS, 0.019” *0.025” SS wire. Space closure was done [Figure 7]. Extraorally, a well-defined facial profile was obtained at the end of the treatment [Figure 8].
| Case Report 2|| |
An 11-year-old female reported to the Department of orthodontics and Dentofacial Orthopedics with a chief complaint of irregularly placed upper and lower teeth in front region of the jaws. On extraoral examination, she had a concave facial profile with retrognathic maxilla, obtuse nasolabial angle, protrusive mandible, and incompetent lips. Intraorally, he had Angle's Class III malocclusion, Class III canine relation on both sides, anterior crossbite and reverse overjet [Figure 9]. The panoramic radiograph showed with impacted canine on upper left side, no missing teeth or pathologies. Cephalometric analysis indicated a skeletal Class III due to posteriorly positioned maxilla along with a horizontal growth pattern with proclined lower incisors and upper incisor inclination [Figure 10].
- Correction of skeletal Class III
- Correction of reverse overjet
- Obtaining Class I molar and canine relationship
- Correction of anterior crossbite
- Achieving a pleasant soft-tissue profile.
Early phase (phase I) of orthopedic treatment was planned to induce harmonious skeletal growth and improve facial aesthetics. It was started with RME followed by face mask therapy for sagittal maxillary advancement, correct skeletal Class III malocclusion. Fixed orthodontic mechanotherapy (Phase II) was done with extraction of all first premolars in upper and lower arch for the final detailing of occlusion.
In the phase I of the treatment was RME till the circummaxillary sutures, sagittal correction was not needed because there is no posterior crossbite. The upper assembly comprised of an acrylic plate with a HYRAX embedded in it. The HYRAX was activated for 14 days with two turns in a day, i.e., 180° in morning and one in evening. After 14 days, the screw was locked and the facemask therapy was started for maxillary protraction [Figure 11]. The facemask was used for another 6 months, for first 2 weeks 8 Oz elastics were used and after that for the next 2½ months 14 Oz elastics were used. Facemask was used as retainer for the next 3 months. Six months after completion of phase I of the treatment, the RME and the facemask were removed and a retention plate with jackscrew was placed to prevent the relapse. In phase II of treatment fixed mechanotherapy was done with extraction of all 1st premolars in upper and lower arch to maintain the molar and canine relation.
The patient was assessed after phase I of treatment with HYRAX and facemask therapy. Progress showed favorable growth of the maxilla, i.e., forward growth of maxilla and the mandibular growth is restricted which leads to correction of anterior and posterior crossbite [Figure 12]. Postprotraction cephalometric tracings [Figure 13] revealed forward movement of maxilla and counterclockwise rotation of the palatal plane. The ANB angle changed from −8° to 1°. FMA opened from 26° to 27°. Slight labial tipping of the maxillary incisors was also observed. The point A also shifted anteriorly by 6 mm approximately which shows the forward growth of maxilla. In phase II of the treatment extraction of all first premolars was done initial leveling and alignment was done with wire sequence of 0.012” Niti, 0.014” Niti, 0.016” Niti, 0.017 * 0.025” SS, 0.019” *0.025” SS wire. A minor surgery was done to expose the impacted canine and the canine was align with piggy begg wire with dimensions 0.012Niti followed by closure of the remaining space. Extraorally, a well-defined facial profile was obtained at the end of the treatment.
| Discussion|| |
The incidence of Class III malocclusion was found to be 5% in whites and as high as 48% in Japanese. The prevalence in North and South India was approximately 3.4% and 0.3%, respectively. The success of orthodontic treatment with a developing Class III malocclusion depends on the growth of individual and timing of orthodontic or orthopedic intervention. For patients with moderate to severe Class III malocclusions, the decision of whether to treat early or to wait is difficult until the end of growth. Orthopedic treatments might prove effective in children with Class III malocclusion in the short term. Several appliances are used for early treatment of skeletal Class III, including Bionator, Frankel (FR-III), chin cup, double-plate appliance, Eschler appliance “progenic appliance,” and protraction face mask. Takada et al. reported that the forward maxillary displacement with protraction was more favorable before or during the acceleration of a child's pubertal growth spurt. In recent years, face mask therapy with and without palatal expansion has become a common technique used to correct a developing hypoplastic maxillary Class III malocclusion. Maxillary expansion has been advocated as a routine part of Class III treatment caused by maxillary deficiency,,, however, a critical evaluation of expansion in conjunction with maxillary protraction has been limited. Some authors reported that Class III treatment with maxillary expansion and protraction was effective in themaxilla only when it was performed before the peak (cervical Stage 1 or cervical Stage 2). Orthopedic protraction of the maxilla has some limitations, including problems with patient compliance, limited protraction of the maxilla (2–3 mm in 9–12 months), unwanted dentoalveolar effects, and the possibility of relapse as a result of late mandibular growth.,, A combination of maxillary protraction and RME has been used to treat young Class III patients with the maxillary deficiency. The goal of combining RME with maxillary protraction was to disarticulate the maxilla from the surrounding bones connected by circummaxillary sutures and to facilitate the forward movement of the maxilla. Maxillary protraction along the occlusal plane is accompanied by counterclockwise rotation of the palatal plane and downward and backward rotation of the mandible plane, which results in tentative improvement of the skeletal relationship. In these case reports, postprotraction cephalometric radiographs showed a counter clockwise tipping of the palatal plane and an increase in the mandibular plane angle and lower facial height, thus leading to an overall improvement of the facial profile. A significant increase in ANB angle after facemask and RME treatment was due to the forward movement of the maxilla and the backward movement of the mandible. The downward and forward movement of the maxilla and the downward and backward rotation of the mandible improved the maxillomandibular skeletal relationship and the convexity of the profile. Various clinical studies focusing on maxillary protraction described forward and downward movement of the maxilla and a clockwise rotation of the mandible.,,,,,, Mandibular rotation may be due to vertical maxillary movement or a retractive force on the chin. The mandibular rotation resulted in an increase in lower anterior facial height. Age 11 years of Intervention (Face Mask Therapy). An important factor determining the success of treatment for Class III patients is treatment timing. It has been recommended that facemask therapy should be initiated at 6–8 years of age after eruption of maxillary permanent first molar and incisors, that is, early mixed dentition.,,, However, maxillary protraction with bone anchors and Class III elastics has been reported to be successful in the late mixed or permanent dentition phases. Maxillary protraction with or without maxillary expansion? In addition, RME has been recommended as a routine component of the treatment for correction of Class III malocclusion, even in the absence of maxillary constriction because it disarticulates the maxilla and gives rise to cellular responses in the circummaxillary sutures, bringing about a more positive reaction to protraction forces.,, Nevertheless, when used to enhance anterior movement of the maxilla during facemask therapy, preliminary RME does not appear to exert any effect on the efficacy of orthopedic treatment. There are reports that use of RME alone might not properly disarticulate circummaxillary sutures and it might be better dealt with by Alt-RAMEC.,, A meta-analysis showed similar results for protraction with or without expansion.
| Conclusion|| |
An important factor for treatment of Class III malocclusion in growing patient is the origin of malocclusion. The skeletal or dental origin of the malocclusion and in skeletal Class III malocclusions mandibular Prognathism or maxillary deficiency are important for choosing early intervention and selection of the appliance for treatment. The appliances described in this paper can be useful when the clinicians use them in correct manner.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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