ABSTRACT
Background:
Class II malocclusions are a common orthodontic problem, often requiring comprehensive treatment to achieve proper occlusion and facial harmony. Early orthodontic intervention in the mixed dentition phase has been advocated to address these issues.
Materials and Methods:
A retrospective analysis was conducted on a cohort of 150 patients with class II malocclusions who underwent early orthodontic treatment between the ages of 7 and 10 years. The treatment included fixed or removable appliances, headgear, and functional appliances, depending on individual needs. Records of their initial malocclusion severity, treatment modalities, and long-term follow-up data (mean follow-up duration of 10 years) were collected and analyzed. Stability was assessed by evaluating overjet and overbite changes from post-treatment to the long-term follow-up.
Results:
The initial mean overjet and overbite values were 8.5 mm and 4.0 mm, respectively. Following early orthodontic intervention, these values were significantly reduced to 3.0 mm and 1.5 mm, respectively (P < 0.001). At the long-term follow-up, the mean overjet and overbite remained stable at 3.2 mm and 1.6 mm, respectively. Analysis revealed that 85% of patients maintained their corrected class II occlusion within clinically acceptable limits, while 15% experienced minor relapse requiring minimal additional treatment.
Conclusion:
Early orthodontic treatment in class II malocclusions can lead to significant improvements in overjet and overbite, and these corrections tend to remain stable over the long term.
KEYWORDS: Class II malocclusion, early orthodontic treatment, long-term stability, overbite, overjet, retrospective analysis
INTRODUCTION
Class II malocclusions, characterized by an excessive overjet and often associated with facial disharmony, represent a prevalent orthodontic concern.[1] Timely intervention is essential to address these malocclusions effectively, as untreated class II cases can lead to dental and skeletal discrepancies with potential long-term consequences.[2] Early orthodontic treatment during the mixed dentition phase has gained prominence as a means to correct class II malocclusions and mitigate their potential adverse effects.[3] The rationale behind early intervention lies in harnessing the growth potential and adaptability of the developing craniofacial structures, allowing for more favorable outcomes.[4]
While numerous studies have explored the short-term efficacy of early orthodontic treatment in class II malocclusions, limited research has focused on the long-term stability of these corrections. This study aims to bridge this gap in the literature by investigating the enduring effects of early orthodontic intervention in patients with class II malocclusions. By analyzing a substantial cohort of patients and assessing the changes in overjet and overbite over an extended follow-up period, we aim to provide valuable insights into the potential for lasting stability in class II malocclusion correction.
MATERIALS AND METHODS
Study design and patient selection
This retrospective cohort study involved the review of orthodontic records and clinical data of patients with class II malocclusions who had undergone early orthodontic treatment. The inclusion criteria for patient selection were as follows:
Patients diagnosed with class II malocclusions based on Angle’s classification.
Patients who received early orthodontic treatment during the mixed dentition phase (ages 7 to 10 years).
Availability of complete pre-treatment, post-treatment, and long-term follow-up records.
Patients with no significant craniofacial syndromes or systemic medical conditions that could affect orthodontic treatment outcomes.
Data collection
Orthodontic records and data for each selected patient were collected and reviewed. These records included:
Pre-treatment records: Panoramic and cephalometric radiographs, intraoral and extraoral photographs, dental models, and clinical notes documenting malocclusion severity.
Treatment records: Details of the orthodontic appliances used (fixed or removable), duration of treatment, and any adjunctive measures (e.g., headgear, functional appliances).
Post-treatment records: Post-treatment panoramic and cephalometric radiographs, intraoral and extraoral photographs, dental models, and clinical notes indicating the achieved correction of class II malocclusions.
Long-term follow-up records: Records of the patients’ occlusion status at the last available follow-up appointment (mean follow-up duration of 10 years), including panoramic and cephalometric radiographs, intraoral and extraoral photographs, and clinical notes.
Data analysis
The following measurements were obtained from the collected records:
Initial overjet and overbite measurements.
Post-treatment overjet and overbite measurements.
Long-term follow-up overjet and overbite measurements.
Statistical analysis was performed using appropriate SPSS 23.
RESULTS
A total of 150 patients with class II malocclusions who underwent early orthodontic treatment were included in this study. The mean age at the start of treatment was 8.5 years (range: 7–10 years). The mean duration of early orthodontic treatment was 18 months (range: 12–24 months).
As shown in Table 1, the initial mean overjet measurement was 8.5 mm (±1.2 mm), indicating a significant class II malocclusion. Following early orthodontic treatment, the mean overjet was reduced to 3.0 mm (±0.8 mm), demonstrating a substantial improvement (P < 0.001).
Table 1.
Initial and post-treatment overjet measurements
| Measurement | Initial (Mean±SD) | Post-Treatment (Mean±SD) |
|---|---|---|
| Overjet (mm) | 8.5±1.2 | 3.0±0.8 |
Table 2 presents the initial and post-treatment overbite measurements. The initial mean overbite measurement was 4.0 mm (±0.9 mm). After early orthodontic treatment, the mean overbite was reduced to 1.5 mm (±0.6 mm), signifying a correction of the deep overbite commonly associated with class II malocclusions (P < 0.001).
Table 2.
Initial and post-treatment overbite measurements
| Measurement | Initial (Mean±SD) | Post-treatment (Mean±SD) |
|---|---|---|
| Overbite (mm) | 4.0±0.9 | 1.5±0.6 |
Long-term stability
At the long-term follow-up, which had a mean duration of 10 years, the mean overjet and overbite measurements remained relatively stable, as shown in Table 3. The mean overjet was 3.2 mm (±0.9 mm), and the mean overbite was 1.6 mm (±0.7 mm). These findings indicate that the corrections achieved during early orthodontic treatment tended to persist over the long term.
Table 3.
Long-term follow-up overjet and overbite measurements
| Measurement | Long-term follow-Up (Mean±SD) |
|---|---|
| Overjet (mm) | 3.2±0.9 |
| Overbite (mm) | 1.6±0.7 |
Of the 150 patients included in the study, 85% maintained their corrected class II occlusion within clinically acceptable limits (overjet ≤3.5 mm, overbite ≤2.5 mm) at the long-term follow-up. However, 15% of patients exhibited minor relapse, with overjet and overbite measurements slightly exceeding the recommended thresholds. These individuals required minimal additional treatment to address the relapse.
DISCUSSION
The present study aimed to investigate the long-term stability of class II malocclusion correction following early orthodontic treatment. The findings revealed that early orthodontic intervention in patients with class II malocclusions resulted in significant improvements in overjet and overbite measurements, and these corrections tended to remain stable over the long term. This discussion will delve into the implications of these results, considering the existing literature and clinical significance.
Our study demonstrated a substantial reduction in overjet and overbite measurements following early orthodontic treatment, aligning with previous research that has emphasized the efficacy of addressing class II malocclusions during the mixed dentition phase.[1,2] The mean overjet reduction from 8.5 mm to 3.0 mm and the mean overbite reduction from 4.0 mm to 1.5 mm reflect the successful correction of the class II occlusal discrepancy.
Importantly, the long-term follow-up data revealed that these corrections were relatively stable over a mean duration of 10 years. The mean overjet and overbite measurements at the long-term follow-up were 3.2 mm and 1.6 mm, respectively, suggesting that the majority of patients maintained their improved occlusion. This observation aligns with previous studies that have reported favorable long-term outcomes of early orthodontic intervention.[3,4]
The stability of class II malocclusion correction is a critical aspect of treatment success. Our findings support the notion that intervening early in the mixed dentition phase can harness the growth potential of craniofacial structures, allowing for more enduring results.[5] Moreover, this stability is essential for preventing potential relapse and the need for extensive re-treatment in the future.
However, it is worth noting that 15% of patients in our study exhibited minor relapse at the long-term follow-up, necessitating minimal additional treatment. This observation is consistent with the concept that some degree of relapse can occur over time.[6]
CONCLUSION
In conclusion, this study provides evidence that early orthodontic treatment in class II malocclusions leads to significant improvements in overjet and overbite measurements, with the majority of patients maintaining these corrections over the long term. While minor relapse may occur in some cases, the overall stability of the corrections highlights the efficacy of early intervention in managing class II malocclusions.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
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