Early Treatment of Class II Division 1 Malocclusions with Prefabricated Myofunctional Appliances: A Case Report

: Removable functional appliances (RFA) have long been employed to address Class II mal-occlusion, particularly in cases involving a signi ﬁ cant overjet, a deep bite, and molar class 2 issues. Notably divergent from RFA, myofunctional appliances (PMA) o ﬀ er several distinct advantages, including applicability in noncompliant patients, adaptability in cases of dental element scarcity, suitability for allergic patients, impression-free utilization, and reduced costs. Within the array of clinical cases treated with PMA, we chose to present an intricate case involving an 8-year-old girl. Our aim was to showcase the immediate e ﬀ ects of PMA and to track the progress over a two-year span. Following one year of PMA treatment, substantial improvements were observed in a large overjet, a deep bite, and lip incompetence—factors often associated with elevated risks of dental trauma. These improvements not only positively impacted dental aesthetics but also engendered normalized nasal respiration and diminished palatal impingement, thereby enhancing the overall quality of life. Upon reaching the two-year mark, the clinical status pertaining to Class II malocclusion remained stable. Further treatment was advised in a subsequent phase to re ﬁ ne imperfections in the dental arch form. Nonetheless, comprehensive data from the prolonged follow-up of patients treated with these appliances are essential to establish robust scienti ﬁ c evidence concerning their long-term e ﬃ cacy.


Introduction
Research indicates that the optimal timing for addressing Class II Division 1 malocclusions is during the early permanent dentition phase.Treating these malocclusions during either the early or late mixed dentition stages did not result in greater efficiency in terms of both treatment duration and outcomes [1].Some studies have suggested that the advantages gained from the early treatment phase diminish when patients undergo comprehensive fixed appliance treatment during adolescence [2,3].Others view the effects of ani 1 , Aida Meto 2,3,4 , Etleva Droboniku 5 , Almiro Gurakuqi 1 , Olja Tanellari 2 , Dorjan Hysi 5 and Luca Fiorillo 2,6,7,8, *

Introduction
Research indicates that the optimal timing for addressing Class II Division 1 malocclusions is during the early permanent dentition phase.Treating these malocclusions during either the early or late mixed dentition stages did not result in greater efficiency in terms of both treatment duration and outcomes [1].Some studies have suggested that the advantages gained from the early treatment phase diminish when patients undergo comprehensive fixed appliance treatment during adolescence [2,3].Others view the effects of early treatment as a form of "growth mortgage", where the growth borrowed prematurely is repaid later on [4].Nonetheless, experiential insights propose that under specific circumstances such as psychosocial distress, susceptibility to accidents, or overall family convenience, initiating treatment in the early stages might offer benefits to the patient [3,5].In this context, early intervention for a significant overjet finds justification, especially as it is considered a risk factor for dental trauma [6].
For numerous years, removable functional appliances (RFA) have been employed to rectify Class II malocclusion.Short-term evidence underscores the efficacy of RFA in ameliorating Class II malocclusion, primarily exerting effects on the dentoalveolar aspect rather than the skeletal component [7].Prefabricated functional appliances (PFA), typically crafted from soft elastomeric materials, emerged in the 1980s [8].These appliances are utilized to correct Class II Division 1 malocclusions through a fusion of functional appliance traits, such as mandibular advancement, with eruption guidance facilitated by soft tissue shields.The appliance is outfitted with guiding slots for the anterior teeth, facilitating their adjustment into conventional intermaxillary relationships [9].
While PFA have been accessible for several decades, it is only in recent years that clinical trials comparing their effects with more traditional functional appliances have emerged.Some researchers have concluded that there is no discernible distinction in effectiveness between PFA and Andresen Appliances in rectifying overjet, overbite, sagittal molar relation, and lip seal [10].Controlled clinical studies have demonstrated that PFA can ameliorate Class II Division 1 malocclusions in compliant patients, potentially offering a more cost-effective alternative compared to conventional functional appliances [11].
In another systematic review that juxtaposed the efficacy of prefabricated myofunctional appliances (PMAs) with activators for treating Class II Division 1 malocclusion, researchers concluded that in the short term, activators outperformed PMAs in correcting overjet.However, over the long term, no significant disparities were observed between the two appliances.Beyond their impact on dental relationships, unlike activators, PMAs have the capacity to address issues like mouth breathing and atypical swallowing by enhancing intra and extra oral muscular equilibrium.Authors assert that the main advantage of PMAs appears to lie in their cost-effectiveness [12].
The primary goal of this study was to evaluate the efficacy of a one-year active treatment involving the utilization of a PMA in children aged 8 to 9, with a specific focus on improving occlusal relationships.This was followed by a comprehensive two-year follow-up period.From a diverse pool of clinical cases treated with PMAs, we specifically chose a complex case involving an 8-year-old girl.Our intention was to underscore the immediate impact of PMAs and meticulously monitor her progress over the ensuing two-year duration.

Case Selection
In this instance, we enrolled an 8-year-old girl whose parents expressed concerns about her anterior maxillary appearance and persistent gingiva irritation.They reported that she had encountered dental trauma twice as a result of a crash.Additionally, they noted her tendency toward mouth breathing and snoring during sleep.Recently, an otorhinolaryngologist recommended and performed an adenoidectomy to address confirmed adenoid hypertrophy.Informed about the functioning of the PMA at the outset of treatment, the parents granted their consent for the procedure.

Patient Examination
During extraoral examination were observed lip incompetence, a reduced lower facial height, and an accentuated convex profile (Figure 1A).In the intraoral examination, evident features were a significant overjet, a deep bite, a Class II molar sagittal relationship according to Angle's classification, inflamed gingiva, and palatal impingement due to the deep bite.Additionally, there was a crown fracture on the upper right central incisor, tooth #11, with no pulp involvement (classified as Class 2 dental trauma following McDonald's classification) [13] (Figure 1B).The patient presented a narrow maxillary dental arch and a deep palate; also, she demonstrated ease in mandibular movements and displayed no indications of TMJ issues.While she was capable of nasal breathing when her lips were sealed, the proclined maxillary incisors caused discomfort.Additionally, the panoramic X-ray corroborated the proper positioning of all permanent teeth, including wisdom teeth, at various stages of development (Figure 1C).

Cephalometric Analysis
Figure 2 illustrates the lines utilized for angular and linear measurements in the cephalometric tracing.Pre-treatment cephalometric measurements confirmed a skeletal Class II Division 1, characterized by an ANB angle of 8°, a reduced facial angle (N-Pg ^ PF° 78°), a hypo-divergent facial pattern (FMA angle 23°), a 6 mm overjet, a 4.5 mm deep bite, proclined maxillary incisors (Is long axis to PF 113°), and an IMPA of 107° (Table 1).Cephalometric measurements demonstrated a ratio of 1.2 between one-third of the middle face and one-third of the lower face.The patient presented a narrow maxillary dental arch and a deep palate; also, she demonstrated ease in mandibular movements and displayed no indications of TMJ issues.While she was capable of nasal breathing when her lips were sealed, the proclined maxillary incisors caused discomfort.Additionally, the panoramic X-ray corroborated the proper positioning of all permanent teeth, including wisdom teeth, at various stages of development (Figure 1C).

Cephalometric Analysis
Figure 2 illustrates the lines utilized for angular and linear measurements in the cephalometric tracing.Pre-treatment cephalometric measurements confirmed a skeletal Class II Division 1, characterized by an ANB angle of 8 • , a reduced facial angle (N-Pg ˆPF • 78 • ), a hypo-divergent facial pattern (FMA angle 23 • ), a 6 mm overjet, a 4.5 mm deep bite, proclined maxillary incisors (Is long axis to PF 113 • ), and an IMPA of 107 • (Table 1).Cephalometric measurements demonstrated a ratio of 1.2 between onethird of the middle face and one-third of the lower face.

Treatment Approach and Protocol
We decided to treat her using a prefabricated appliance (PMA), guided by measurements of the upper incisors.Initially, we applied a fixed retainer to all mandibular incisors, followed by the application of the appliance.The patient was advised to wear the device at night.Since all of her permanent incisors were fully erupted and considering the significant overjet, she was also asked to use the appliance for 2-3 h during the day, occasionally clenching her jaws to ensure a proper fit.

Treatment Approach and Protocol
We decided to treat her using a prefabricated appliance (PMA), guided by measurements of the upper incisors.Initially, we applied a fixed retainer to all mandibular incisors, followed by the application of the appliance.The patient was advised to wear the device at night.Since all of her permanent incisors were fully erupted and considering the significant overjet, she was also asked to use the appliance for 2-3 h during the day, occasionally clenching her jaws to ensure a proper fit.
We emphasized that any observation of gingival damage should prompt her to contact us immediately.Otherwise, the first follow-up appointment was set for 4 weeks later.During this first visit, we evaluated the stability of the appliance, which was found to be satisfactory, eliminating the need for any tooth or appliance adjustments to improve retention.The patient demonstrated excellent collaboration, allowing us to maintain the same appliance according to the maintenance protocol.
Subsequent appointments occurred every 8 weeks over a year.After the first year, the follow-up plan was to use a PMA as a retainer, with follow-up visits scheduled every six months.Figure 3 displays images of the patient wearing the appliance.Table 1.Cephalometric measurements before and after orthodontic treatment.

Before
After Normal We emphasized that any observation of gingival damage should prompt her to contact us immediately.Otherwise, the first follow-up appointment was set for 4 weeks later.During this first visit, we evaluated the stability of the appliance, which was found to be satisfactory, eliminating the need for any tooth or appliance adjustments to improve retention.The patient demonstrated excellent collaboration, allowing us to maintain the same appliance according to the maintenance protocol.
Subsequent appointments occurred every 8 weeks over a year.After the first year, the follow-up plan was to use a PMA as a retainer, with follow-up visits scheduled every six months.Figure 3 displays images of the patient wearing the appliance.

Treatment Approach and Protocol
We decided to treat her using a prefabricated appliance (PMA), guided by measurements of the upper incisors.Initially, we applied a fixed retainer to all mandibular incisors, followed by the application of the appliance.The patient was advised to wear the device at night.Since all of her permanent incisors were fully erupted and considering the significant overjet, she was also asked to use the appliance for 2-3 h during the day, occasionally clenching her jaws to ensure a proper fit.
We emphasized that any observation of gingival damage should prompt her to contact us immediately.Otherwise, the first follow-up appointment was set for 4 weeks later.During this first visit, we evaluated the stability of the appliance, which was found to be satisfactory, eliminating the need for any tooth or appliance adjustments to improve retention.The patient demonstrated excellent collaboration, allowing us to maintain the same appliance according to the maintenance protocol.
Subsequent appointments occurred every 8 weeks over a year.After the first year, the follow-up plan was to use a PMA as a retainer, with follow-up visits scheduled every six months.Figure 3 displays images of the patient wearing the appliance.

Outcomes of the Treatment at the One-Year Follow-Up
During the initial appointment, after 4 weeks of treatment with the PMA, the parents reported that the patient had ceased snoring at night.Notably, the patient's profile exhibited improvement toward a normal convexity (Figure 4A).Subsequent appointments revealed progressive enhancements in the significant overjet and overbite.These improvements led to a reduction in palatal impingement and a gradual establishment of natural lip competence.The patient achieved normal nasal breathing, and her gingiva displayed a healthy natural color.Following a year of the PMA treatment, the Class II molar relationship transitioned toward a Class I molar relationship (Figure 4B).

Outcomes of the Treatment at the One-Year Follow-up
During the initial appointment, after 4 weeks of treatment with the PMA, the parents reported that patient had ceased snoring at night.Notably, patient s profile exhibited improvement toward a normal convexity (Figure 4A).Subsequent appointments revealed progressive enhancements in the significant overjet and overbite.These improvements led to a reduction in palatal impingement and a gradual establishment of natural lip competence.The patient achieved normal nasal breathing, and her gingiva displayed a healthy natural color.Following a year of the PMA treatment, the Class II molar relationship transitioned toward a Class I molar relationship (Figure 4B).Both dental arches exhibited improvements, with particular enhancement seen in the maxillary arch form.Additionally, the palate was notably less deep than it was prior to treatment (Figure 5).Both dental arches exhibited improvements, with particular enhancement seen in the maxillary arch form.Additionally, the palate was notably less deep than it was prior to treatment (Figure 5).

Outcomes of the Treatment at the One-Year Follow-up
During the initial appointment, after 4 weeks of treatment with the PMA, the parents reported that the patient had ceased snoring at night.Notably, the patient s profile exhibited improvement toward a normal convexity (Figure 4A).Subsequent appointments revealed progressive enhancements in the significant overjet and overbite.These improvements led to a reduction in palatal impingement and a gradual establishment of natural lip competence.The patient achieved normal nasal breathing, and her gingiva displayed a healthy natural color.Following a year of the PMA treatment, the Class II molar relationship transitioned toward a Class I molar relationship (Figure 4B).Both dental arches exhibited improvements, with particular enhancement seen in the maxillary arch form.Additionally, the palate was notably less deep than it was prior to treatment (Figure 5).

Cephalometric Values after One Year of Treatment
We conducted identical measurements on a lateral cephalometric X-ray after one year of treatment (Figure 6).The results displayed a diminished ANB angle (from 7 • to 4 • ), indicating an improvement in skeletal Class II Division 1.There was minimal alteration in the facial angle (from 78 • to 79 • ) and the FMA angle (from 23 • to 25 • ).Additionally, improvements were observed in the overjet (from 6 mm to 3 mm), deep bite (from 4 mm to 2.5 mm), and inclination of the maxillary incisor (from 114 • to 109 • ).

Cephalometric Values after One Year of Treatment
We conducted identical measurements on a lateral cephalometric X-ray after one year of treatment (Figure 6).The results displayed a diminished ANB angle (from 7° to 4°), indicating an improvement in skeletal Class II Division 1.There was minimal alteration in the facial angle (from 78° to 79°) and the FMA angle (from 23° to 25°).Additionally, improvements were observed in the overjet (from 6 mm to 3 mm), deep bite (from 4 mm to 2.5 mm), and inclination of the maxillary incisor (from 114° to 109°).A notable increase in the IMPA angle was observed, despite the fact that all mandibular incisors were bonded with a fixed retainer (Table 1).Cephalometric measurements revealed a ratio of 1.02 between one-third of the middle face and one-third of the lower face.

Situation of the Treatment after Two Years
Two years after initiating the treatment, our patient returned for a follow-up.However, over the last six months, she displayed a lack of cooperation in wearing the appliance during the night.Nonetheless, her situation remained stable in terms of profile convexity, lip competence, mouth breathing, molar class, overjet, and overbite (Figure 7).A second treatment phase involving a rapid maxillary expander was recommended to address the transverse discrepancy.A notable increase in the IMPA angle was observed, despite the fact that all mandibular incisors were bonded with a fixed retainer (Table 1).Cephalometric measurements revealed a ratio of 1.02 between one-third of the middle face and one-third of the lower face.

Situation of the Treatment after Two Years
Two years after initiating the treatment, our patient returned for a follow-up.However, over the last six months, she displayed a lack of cooperation in wearing the appliance during the night.Nonetheless, her situation remained stable in terms of profile convexity, lip competence, mouth breathing, molar class, overjet, and overbite (Figure 7).A second treatment phase involving a rapid maxillary expander was recommended to address the transverse discrepancy.

Cephalometric Values after One Year of Treatment
We conducted identical measurements on a lateral cephalometric X-ray after one year of treatment (Figure 6).The results displayed a diminished ANB angle (from 7° to 4°), indicating an improvement in skeletal Class II Division 1.There was minimal alteration in the facial angle (from 78° to 79°) and the FMA angle (from 23° to 25°).Additionally, improvements were observed in the overjet (from 6 mm to 3 mm), deep bite (from 4 mm to 2.5 mm), and inclination of the maxillary incisor (from 114° to 109°).A notable increase in the IMPA angle was observed, despite the fact that all mandibular incisors were bonded with a fixed retainer (Table 1).Cephalometric measurements revealed a ratio of 1.02 between one-third of the middle face and one-third of the lower face.

Situation of the Treatment after Two Years
Two years after initiating the treatment, our patient returned for a follow-up.However, over the last six months, she displayed a lack of cooperation in wearing the appliance during the night.Nonetheless, her situation remained stable in terms of profile convexity, lip competence, mouth breathing, molar class, overjet, and overbite (Figure 7).A second treatment phase involving a rapid maxillary expander was recommended to address the transverse discrepancy.The patient returned for a follow-up after 6 months.During this interval, she disclosed that she had consistently used the same appliance every night, contrary to our advice.While the results from the initial year of treatment remained stable, an unexpected outcome emerged-an improvement in the transverse relationship (Figure 8).The patient was highly satisfied with her smile, and the parents eventually consented to an aesthetic restoration for tooth #11 (Figure 9).No further treatment was deemed necessary; however, regular follow-up appointments every six months were recommended.The patient returned for a follow-up after 6 months.During this interval, she disclosed that she had consistently used the same appliance every night, contrary to our advice.While the results from the initial year of treatment remained stable, an unexpected outcome emerged-an improvement in the transverse relationship (Figure 8).The patient was highly satisfied with her smile, and the parents eventually consented to an aesthetic restoration for tooth #11 (Figure 9).No further treatment was deemed necessary; however, regular follow-up appointments every six months were recommended.

Discussion
The Cochrane review s findings indicated that there is no significant advantage to early overjet treatment when compared to treatment during adolescence [14].However, under specific circumstances where a high risk of trauma is evident, early orthodontic intervention might be deemed necessary and beneficial for patients [15].Our study illustrated substantial enhancements in significant aspects such as a large overjet, overbite, and sagittal molar relationship, all of which remained consistent two years post-treatment.These outcomes align with prior investigations exploring various early-growth and developmental-appliance therapies, which have documented a decrease in overjet and overbite among children aged 5-10 years who underwent similar treatments over a comparable timespan.In contrast, the control group displayed a gradual yet consistent rise in overjet and overbite [16][17][18].
Notably, our study achieved simultaneous enhancements in both a large overjet and overbite.This concurrent improvement in overjet can result in improved dental support and greater bite stability.The alignment of teeth at a young age can lead to enhanced The patient returned for a follow-up after 6 months.During this interval, she disclosed that she had consistently used the same appliance every night, contrary to our advice.While the results from the initial year of treatment remained stable, an unexpected outcome emerged-an improvement in the transverse relationship (Figure 8).The patient was highly satisfied with her smile, and the parents eventually consented to an aesthetic restoration for tooth #11 (Figure 9).No further treatment was deemed necessary; however, regular follow-up appointments every six months were recommended.

Discussion
The Cochrane review s findings indicated that there is no significant advantage to early overjet treatment when compared to treatment during adolescence [14].However, under specific circumstances where a high risk of trauma is evident, early orthodontic intervention might be deemed necessary and beneficial for patients [15].Our study illustrated substantial enhancements in significant aspects such as a large overjet, overbite, and sagittal molar relationship, all of which remained consistent two years post-treatment.These outcomes align with prior investigations exploring various early-growth and developmental-appliance therapies, which have documented a decrease in overjet and overbite among children aged 5-10 years who underwent similar treatments over a comparable timespan.In contrast, the control group displayed a gradual yet consistent rise in overjet and overbite [16][17][18].
Notably, our study achieved simultaneous enhancements in both a large overjet and overbite.This concurrent improvement in overjet can result in improved dental support and greater bite stability.The alignment of teeth at a young age can lead to enhanced

Discussion
The Cochrane review's findings indicated that there is no significant advantage to early overjet treatment when compared to treatment during adolescence [14].However, under specific circumstances where a high risk of trauma is evident, early orthodontic intervention might be deemed necessary and beneficial for patients [15].Our study illustrated substantial enhancements in significant aspects such as a large overjet, overbite, and sagittal molar relationship, all of which remained consistent two years post-treatment.These outcomes align with prior investigations exploring various early-growth and developmentalappliance therapies, which have documented a decrease in overjet and overbite among children aged 5-10 years who underwent similar treatments over a comparable timespan.In contrast, the control group displayed a gradual yet consistent rise in overjet and overbite [16][17][18].
Notably, our study achieved simultaneous enhancements in both a large overjet and overbite.This concurrent improvement in overjet can result in improved dental support and greater bite stability.The alignment of teeth at a young age can lead to enhanced stability, as the collagen fibers supporting the teeth are not fully matured during this period [19][20][21].
After one year of treatment, a tendency toward a molar Class I relationship became evident.Furthermore, an enhanced sagittal molar relationship was observed two years following the initiation of treatment, although no significant change was noted in the transversal relationship.This treatment outcome aligns with findings from other studies as well.These studies reported that early intervention with PMAs led to improved occlusion, often eliminating the need for a second stage of treatment.They propose that the early correction of the incisal relationship toward normalcy subsequently results in a normalized sagittal occlusal relationship.The reverse might also be possible [17].However, this remains a hypothesis and requires further investigation to establish its validity.
At the commencement of orthodontic therapy following an adenoidectomy, the patient continued to experience mouth breathing and snoring during sleep.The parents disclosed that the snoring ceased a few weeks after the initiation of the PMA use.Throughout the treatment period, we observed lip competence and nasal breathing.Two years into the treatment, we noted a consistent state of lip competence and absence of mouth breathing.Interestingly, this stability persisted even during the last six months, despite the patient discontinuing the appliance use.
According to Angle's classification, the development of malocclusion is influenced by numerous factors, with respiratory issues being one of them [22].Chronic mouth breathing can be triggered by adenoid hypertrophy, allergies, or habitual behavior [23].The Equilibrium Theory posits that the impact of mouth breathing on facial development hinges not only on its duration but also on the patient's age [24].Nasal obstruction can significantly affect facial growth, although further in-depth research is essential to unravel this intricate relationship [25].
Previous studies have suggested that PMAs can alter the airway volume and address sleep-disordered breathing in children [12].In our case, we believe that employing a PMA contributed to the amelioration of a habitual mouth breathing behavior, particularly when no obstructive impediments remained following the adenoidectomy.Additionally, studies have highlighted the significance of treating deep bites with palatal impingement based on the Index of Orthodontic Treatment Need (IOTN) [26].Our case demonstrated a reduction in palatal impingement after one year of treatment, preventing soft tissue trauma owing to the enhanced sagittal and vertical alignment of anterior teeth.Consequently, the decrease in palatal impingement stands as another favorable outcome of the orthodontic intervention.
Prior to commencing orthodontic treatment, our patient had experienced two instances of anterior dental trauma.However, throughout the orthodontic intervention involving PMA and the subsequent two-year follow-up, no such incidents occurred.This improved outcome can likely be attributed to the enhancement of both a substantial overjet and lip competence, along with an increased awareness to exercise caution during daily activities.In the context of the literature, a significant overjet is recognized as a dental risk factor associated with trauma, thereby justifying early treatment if such a condition is present [15,27].
Patient compliance stands as a pivotal consideration throughout treatment and warrants further discussion.Thankfully, our patient displayed remarkable cooperation and consistently adhered to the prescribed treatment protocol during the initial year.Our provision of ongoing motivation and support proved indispensable in achieving the desired outcomes.Notably, our patient's maxillary central incisors were fully erupted at the outset of therapy.If the permanent incisors had not yet fully emerged, night-time appliance use might have sufficed [28].However, given the necessity to reposition them more favorably and considering the presence of a significant overjet, prolonging the appliance usage was imperative for achieving optimal results.Patient compliance, coupled with unwavering encouragement, bears significant weight, particularly as follow-up is generally recommended until all permanent teeth have erupted and the growth spurt has concluded.
The patient and her parents expressed great satisfaction with the outcomes of the treatment.The parents revealed that their daughter exhibited heightened motivation at school and improved self-esteem following the treatment.Numerous studies have under-scored how orthodontic interventions can substantially impact a patient's quality of life [13,29,30].
It is important to reiterate that throughout both the treatment phase and the subsequent observation period, our patient did not experience any dental trauma.This positive outcome could potentially be attributed to the amelioration of risk factors associated with dental trauma.However, a broader inquiry arises: are Traumatic Dental Injuries (TDI) solely linked to dental trauma?Existing research has highlighted that TDIs are interconnected with various other risk factors, including obesity [31,32], attention deficit hyperactivity disorder (ADHD) [33], epilepsy [34], cerebral palsy [35], impaired vision/hearing [36], oral piercing [37], and educational level/socio-economic status [38][39][40].The prevalence of dental trauma remains notably high among young individuals.The prevention of dental trauma should encompass an ongoing dissemination of information concerning risk factors and appropriate actions to take in case of such incidents [41].
We observed a consistent sagittal molar relationship two years after the initiation of therapy.However, the transversal relationship did not exhibit similar stability, possibly due to the patient discontinuing appliance use in the final six months of the observation period.Initially, we recommended the application of rapid maxillary expansion to address this issue, but the patient opted to use the PMA only during nighttime for the subsequent six months.Surprisingly, a normal transverse relationship emerged, defying our expectations.This unexpected outcome could potentially be attributed to the extended duration of the PMA use.
Another crucial aspect is to address is the patient's compliance.Our patient demonstrated exceptional cooperation and diligently adhered to the prescribed protocol throughout the initial year of treatment.We consistently made efforts to provide motivation, which played a pivotal role in achieving favorable outcomes.Given that our patient's maxillary central incisors were already fully erupted, daytime appliance wear was imperative for successful treatment.This is because the repositioning of teeth necessitates more time and effort compared to guiding erupting teeth into their proper positions.Compliance also remains a consideration during the retention phase.In this case, the same appliance serves as a nighttime retainer, with the frequency eventually transitioning to every other night.
In terms of follow-up, it is generally advisable to continue until all permanent teeth have emerged and the growth spurt has concluded.Considering cooperation, initiating treatment earlier-during the eruption of permanent incisors-would be preferable.At that stage, nocturnal appliance wear suffices for correction, obviating the need for daytime usage [28].
Patient compliance is crucial for achieving optimal results, as the appliance must be worn for an extended period of time, at least until the growth spurt is completed.In addition to potentially reduced costs, the use of a PMA may offer other advantages.However, further research is needed to assess their effectiveness both in the short term and long term.

Conclusions
PMA has demonstrated its effectiveness in addressing increased overjet, overbite, and Class II malocclusion during the early mixed dentition phase.This often leads to the achievement of improved or normal occlusion, frequently negating the necessity for additional orthodontic intervention.Furthermore, PMA usage has been associated with enhanced lip proficiency and the successful correction of habitual mouth breathing, facilitating the transition to normal nasal breathing.It is worth noting that these treatments have also yielded noticeable enhancements in facial profile and overall quality of life for patients.

Figure 1 .
Figure 1.Patient prior to commencing orthodontic treatment.Panel (A) depicts the extraoral examination, followed by Panel (B) showcasing the intraoral examination.Panel (C) presents the panoramic X-ray.

Figure 1 .
Figure 1.Patient prior to commencing orthodontic treatment.Panel (A) depicts the extraoral examination, followed by Panel (B) showcasing the intraoral examination.Panel (C) presents the panoramic X-ray.

Figure 2 .
Figure 2. Depiction of the pre-treatment cephalometric analysis.

Figure 2 .
Figure 2. Depiction of the pre-treatment cephalometric analysis.

Figure 2 .
Figure 2. Depiction of the pre-treatment cephalometric analysis.

Figure 3 .
Figure 3. Patient exhibiting the appliance inside the mouth, revealing lip incompetence.

Figure 4 .
Figure 4.The patient after one year of PMA treatment.Panel (A) highlights the enhancement in the extraoral presentation and profile.Panel (B) demonstrates the shift from a Class II molar relationship to a Class I molar relationship.

Figure 5 .BFigure 4 .
Figure 5. Alterations in dental arch forms (maxillary and mandibular) before treatment (Left panel) and after one year with PMA (Right panel).

Figure 3 .
Figure 3. Patient exhibiting the appliance inside the mouth, revealing lip incompetence.

Figure 4 .
Figure 4.The patient after one year of PMA treatment.Panel (A) highlights the enhancement in the extraoral presentation and profile.Panel (B) demonstrates the shift from a Class II molar relationship to a Class I molar relationship.

Figure 5 .BFigure 5 .
Figure 5. Alterations in dental arch forms (maxillary and mandibular) before treatment (Left panel) and after one year with PMA (Right panel).

Figure 6 .
Figure 6.Cephalometric status after one year of treatment.

Figure 6 .
Figure 6.Cephalometric status after one year of treatment.

Figure 6 .
Figure 6.Cephalometric status after one year of treatment.

Figure 7 .
Figure 7. Patient two years post-treatment with PMA.Panel (A) displays the extraoral examination, while Panel (B) presents the intraoral condition.

Figure 8 .
Figure 8. Patient s condition at two years and six months post-treatment with PMA.Panel (A) illustrates the extraoral examination, while Panel (B) provides an overview of the intraoral situation.

Figure 8 . 7 Figure 7 .
Figure 8. Patient's condition at two years and six months post-treatment with PMA.Panel (A) illustrates the extraoral examination, while Panel (B) provides an overview of the intraoral situation.

Figure 8 .
Figure 8. Patient s condition at two years and six months post-treatment with PMA.Panel (A) illustrates the extraoral examination, while Panel (B) provides an overview of the intraoral situation.

Table 1 .
Cephalometric measurements before and after orthodontic treatment.