Summary
Long-term dental stability is one of the main objectives following combined orthodontic and orthognathic surgical treatment. It is influenced by multiple factors such as surgical, patient-related, and orthodontic aspects. While recent reviews mainly focus on short-term dental changes (0.5–2 years), longer follow-up dental stability remains hardly reviewed.
The aim of this study was to evaluate long-term stability of dental and dentolabial changes following combined orthodontic and orthognathic surgical treatment with a minimum follow-up period of 5 years.
A systematic search was conducted up to December 2019 using Pubmed, Embase, Web of Science, and Cochrane Central.
Randomized controlled trials (RCTs), prospective and retrospective cohort studies, and case series with a minimum of 10 patients, which reported long-term dental stability following combined orthodontic and orthognathic treatment, were included.
Long-term changes were assessed for overjet, overbite, maxillary, and mandibular incisors’ position and relationship of lip position to maxillary and mandibular incisors. Risk of bias was assessed according to the Cochrane Handbook.
Following the screening of 3178 articles, 11 studies were included (2 RCT, 9 retrospective) with a postoperative follow-up period ranging from 5 to 15 years. A decrease in overjet was observed for patients with skeletal class III malocclusion, whereas overjet increased in class II patients at long-term follow-up. Overbite increased in class II patients, whereas class III showed variable results. The lower incisor position was more stable vertically than horizontally; the latter showing more outcome variability. Dentolabial changes corresponded to the normal ageing process and results were not clinically significant after long-term follow-up.
Current evidence suggests variability of dental and dentolabial stability in both skeletal class II and III patients. Further prospective studies are required to develop guidelines for long-term follow-up assessment using computer tomography or cone-beam computed tomography imaging, before final conclusions can be drawn.
The protocol for this systematic review (CRD42020133844) was registered in the International Prospective Register of Systematic Reviews (PROSPERO).
Introduction
In patients with severe dental and skeletal deformities, combined orthodontic treatment and orthognathic surgery is necessary to achieve facial balance and normal occlusion. The most commonly performed surgical procedures are mandibular bilateral sagittal split osteotomy\ (BSSO) and maxillary Le Fort I osteotomy (1, 2). One of the main objectives after combined orthodontic and orthognathic surgical treatment is dental stability, which can be categorized into short- and long-term stability. Short-term stability is seen as a physiological adaptation, directly related to the post-surgical healing and orthodontic treatment. On the other hand, long-term stability is influenced by multiple factors that can be grouped into surgical, patient-related, and orthodontic factors (3, 4). The surgical factors involve condylar repositioning in the glenoid fossa, type and material of fixation, and surgeon experience. Patient-related factors include masticatory function, interdigitation, neuromuscular adaptation, patient age, type of skeletal pattern or a response to global growth, aberrant behaviour of the orofacial musculature, and pressure from adaptive posturing of the tongue. Finally, the pre- and post-operative orthodontic treatment phase is also crucial for providing a stable occlusion over a long-term period. Preoperative orthodontic treatment involves dental alignment and levelling, dental decompensation, and arch coordination to maximize optimal surgical repositioning of the jaw. Postoperative orthodontic treatment ensures refinement of occlusion and retention. A dental relapse of ≥2 mm at postoperative follow-up is considered to be clinically significant (4).
Recent studies investigating postoperative dental stability mainly focussed on dental changes between 6 months and 2 years (5). Studies with a longer follow-up time still remains hardly reviewed. Therefore, the aim of the present systematic review was to analyse literature related to long-term dental and dentolabial changes following combined orthodontic treatment and orthognathic surgery with a minimum follow-up period of at least 5 years.
Materials and methods
Protocol and registration
The PRISMA (Preferred Reporting Items for Systematic Reviews) guidelines were followed to ensure transparency and comprehensiveness of this systematic review (6). A search protocol was specified in advance and registered at PROSPERO (International prospective register of systematic reviews, reference number: CRD42020133844). Following completion of the review, the protocol was slightly altered and updated at PROSPERO to report previously missing and/or incorrect information. The alterations included addition of 5 years follow-up and case series involving at least 10 patients in the inclusion criteria. Additionally, the risk of bias tool was updated from MINORS to the ROBINS-I tool for non-randomized studies and the Revised Cochrane risk of bias assessment tool for randomized studies (7, 8).
Eligibility criteria
Inclusion and exclusion criteria of the selected studies are summarized in Supplementary Table 1. Studies before the year 2000 were excluded as before that time most evidence concentrated mostly on wire fixation during orthognathic surgery.
PICOS model
Type of participants (P)
Patients with skeletal malocclusion who underwent combined orthodontic and orthognathic surgical treatment.
Type of interventions (I)
Intervention included combined orthodontic and orthognathic surgery (BSSO, one or multiple-piece Le Fort I osteotomy or bimaxillary surgery) treatment for the correction of skeletal malocclusion with a follow-up of at least 5 years.
Type of comparisons (C)
The effects on dental tissue were compared (C) over time considering different skeletal classes, type of osteotomy and surgical procedure.
Type of outcome measures (O)
- Occlusal parameters (overjet, overbite, canine and molar class, canine and molar transversal width, dental midline) measured by clinical examination, dental casts, lateral cephalometry, cone-beam computed tomography (CBCT) or computer tomography (CT).
- Dental changes: maxillary and mandibular incisors’ position.
- Dentolabial changes: relationship of maxillary/mandibular incisors to upper and lower lip related measurements.
- Aesthetic outcome: patient satisfaction, psychosocial benefits.
Type of studies (S)
Randomized controlled trials (RCTs), prospective and retrospective cohort studies, and case series with a minimum of 10 patients, which evaluated the long-term dental and dentolabial changes after combined orthodontic and orthognathic surgical treatment with a follow-up of at least 5 years.
Aims
The aim of this study was to evaluate the long-term dental and dentolabial changes for patients with skeletal malocclusion who underwent combined orthodontic and orthognathic surgical treatment with a minimum follow-up period of 5 years.
Search Strategy, data collection and data extraction
The search strategy was developed for Pubmed, Embase, Web of Science, and Cochrane. The electronic databases were searched up until December 2019. The search strategy included a combination of controlled vocabulary and free-text terms and was run with the recommended EMBASE and Medline filters to identify RCTs, prospective studies, retrospective studies, and case series with a minimum of 10 patients. The full search strategy for the different databases is described in Supplementary Table 2. The search was restricted to articles written in English. Additionally, all references in earlier systematic reviews and selected full-text articles were manually screened for potentially useful articles. Three observers screened all titles and abstracts identified through the electronic searches independently. Full-text articles of studies fulfilling inclusion criteria were obtained. Articles were then independently assessed by all observers to determine whether they met all inclusion criteria. Disagreements were resolved by discussion. After selection, data extraction and risk of bias assessment were performed by two observers. Later, the information was confirmed by the third observer. Two authors were contacted by mail concerning relevant data in the original article; however, both authors failed to respond (4, 9). The unit of measurement for the different outcomes were millimetres and/or degrees.
Quality assessment
Three observers independently performed the risk of bias assessment, any disagreement was resolved by consensus (Supplementary Tables 3 and 4). For non-randomized studies, the ROBINS-I tool was used (7), where seven different domains received a judgement of low, moderate, and serious or critical risk of bias. The two randomized studies were evaluated with the revised Cochrane risk of bias assessment tool (8). Furthermore, the quality of evidence related to the included articles was determined using the GRADE approach (10). A meta-analysis was not possible due to the presence of substantial heterogeneity among included studies, related to the follow-up intervals and assessment methodologies with variable outcome measurements.
Results
Study selection
A total of 4266 articles were identified through database searching. After removal of duplicates and screening titles and abstracts, 214 potentially eligible articles were selected (Figure 1). Out of these, 197 were excluded for the following reasons: literature reviews, no dental outcome, case series with fewer than 10 patients, and follow-up of less than 5 years. Additional records were identified through references. After that, 18 full-text articles were assessed for eligibility; of which, seven articles were excluded: 4 articles did not report long-term dental outcomes (11–14), 2 articles used wire fixation (15, 16), and 1 article had fewer than 10 patients (17). Finally, a total of 11 articles were identified for inclusion in this review: two RCTs (18, 19) and nine retrospective cohort studies (4, 18–25).
Prisma 2009 flow diagram.
Characteristics of the participants and interventions
Supplementary Table 5 provides detailed overview of patient demographics and study characteristics of the included studies. A total of 917 patients in all included studies were followed for 5 years or more. The estimated mean age weighted by study size was 27 years; however, two studies failed to provide this information (4, 20). In addition, seven studies provided sex distribution: 147 females (59%) and 102 males (41%) (9, 20–25). None of the articles reported sample size calculations. Ten articles (4, 18–26) reported the use of rigid internal fixation (RIF); however, one study did not specify which fixation method was used (9). Nevertheless, the latter was included in this review due to the high probability of RIF considering their previous publication in 2007, where 60% of the cases had rigid fixation. Lateral cephalograms were obtained to assess dental changes at different follow-up times based on a reference coordinate system (4, 9, 26, 18–25).
Characteristics of outcome measures
The reported outcome measures were divided into four categories: (1) skeletal, (2) dental, (3) dentolabial, and (4) soft tissue. This systematic review focussed specifically on dental and dentolabial outcomes. Dental outcomes included overjet (OJ), overbite (OB), upper incisor position (U1), and lower incisor position (L1). In addition, dentolabial outcomes considered upper and lower incisor position in relation to lip landmarks and lip position. No article described patient satisfaction and clinical examination-related outcomes; however, Proffit et al. reported changes in psychosocial indices from a period of immediate to 5 years post-operatively (23).
Results of individual studies
Tables 1–5 summarize results reported from the included studies divided by author, skeletal class, mean outcome measurement or change in time, clinical relevance, and impact of the outcome. Each study outcome was assessed based on different timelines and classified into baseline or before surgery, post-surgery, and long-term follow-up (5 years or more).
Overjet changes after combined orthodontic and orthognathic surgical treatment in class II and III patients during long-term follow-up.
| Reference | Skeletal class | Mean OJ (mm ± SD) | OJ relapse (between post-treatment and longest follow-up) | Clinically significanta | |||||
|---|---|---|---|---|---|---|---|---|---|
| Baseline | Post-treatment | 5 y | > 5 y | Change (Δ mm ± SD) | Estimated mean change (%) | Patients with 2- to 4-mm changes (%) | |||
| Bailey et al. (26) | III | — | — | — | — | −0.3 (1.0) to 0.00 (1.2) | — | — | No |
| Bailey et al. (9) | III | — | — | — | — | −1.6 (0.9) to −0.6 (1.4) | — | 25%↓ and 2%↓ > 4 mm | Yes |
| Brandtner et al. (20) | II | 5.7 (3.2) | 2.0 (0.9) | — | 2.5 (1.3) | — | 25% | — | No |
| Dolce et al. (18) | II | 7.5 (0.5) | 2.7 (0.1) | 3.7 (0.1) | — | — | 37% | — | No |
| Joss and Thüer (25) | III | −3.2 (4.0) | — | — | 2.2 (1.7) | −0.1 (1.0) | — | — | No |
| Proffit et al. (4) | II | — | — | — | — | — | — | 4%↓ and 8%↑ | Yes |
| Proffit et al. (23) | II | — | — | — | — | 1.0 (1.1) | — | 20% ↑ | Yes |
| Reference | Skeletal class | Mean OJ (mm ± SD) | OJ relapse (between post-treatment and longest follow-up) | Clinically significanta | |||||
|---|---|---|---|---|---|---|---|---|---|
| Baseline | Post-treatment | 5 y | > 5 y | Change (Δ mm ± SD) | Estimated mean change (%) | Patients with 2- to 4-mm changes (%) | |||
| Bailey et al. (26) | III | — | — | — | — | −0.3 (1.0) to 0.00 (1.2) | — | — | No |
| Bailey et al. (9) | III | — | — | — | — | −1.6 (0.9) to −0.6 (1.4) | — | 25%↓ and 2%↓ > 4 mm | Yes |
| Brandtner et al. (20) | II | 5.7 (3.2) | 2.0 (0.9) | — | 2.5 (1.3) | — | 25% | — | No |
| Dolce et al. (18) | II | 7.5 (0.5) | 2.7 (0.1) | 3.7 (0.1) | — | — | 37% | — | No |
| Joss and Thüer (25) | III | −3.2 (4.0) | — | — | 2.2 (1.7) | −0.1 (1.0) | — | — | No |
| Proffit et al. (4) | II | — | — | — | — | — | — | 4%↓ and 8%↑ | Yes |
| Proffit et al. (23) | II | — | — | — | — | 1.0 (1.1) | — | 20% ↑ | Yes |
OJ, overjet; Δ, change; ↓, decrease; ↑, increase.
aClinically significant: changes > 2 mm during follow-up are considered clinically relevant, changes < 2 mm are not clinically relevant.
Overjet changes after combined orthodontic and orthognathic surgical treatment in class II and III patients during long-term follow-up.
| Reference | Skeletal class | Mean OJ (mm ± SD) | OJ relapse (between post-treatment and longest follow-up) | Clinically significanta | |||||
|---|---|---|---|---|---|---|---|---|---|
| Baseline | Post-treatment | 5 y | > 5 y | Change (Δ mm ± SD) | Estimated mean change (%) | Patients with 2- to 4-mm changes (%) | |||
| Bailey et al. (26) | III | — | — | — | — | −0.3 (1.0) to 0.00 (1.2) | — | — | No |
| Bailey et al. (9) | III | — | — | — | — | −1.6 (0.9) to −0.6 (1.4) | — | 25%↓ and 2%↓ > 4 mm | Yes |
| Brandtner et al. (20) | II | 5.7 (3.2) | 2.0 (0.9) | — | 2.5 (1.3) | — | 25% | — | No |
| Dolce et al. (18) | II | 7.5 (0.5) | 2.7 (0.1) | 3.7 (0.1) | — | — | 37% | — | No |
| Joss and Thüer (25) | III | −3.2 (4.0) | — | — | 2.2 (1.7) | −0.1 (1.0) | — | — | No |
| Proffit et al. (4) | II | — | — | — | — | — | — | 4%↓ and 8%↑ | Yes |
| Proffit et al. (23) | II | — | — | — | — | 1.0 (1.1) | — | 20% ↑ | Yes |
| Reference | Skeletal class | Mean OJ (mm ± SD) | OJ relapse (between post-treatment and longest follow-up) | Clinically significanta | |||||
|---|---|---|---|---|---|---|---|---|---|
| Baseline | Post-treatment | 5 y | > 5 y | Change (Δ mm ± SD) | Estimated mean change (%) | Patients with 2- to 4-mm changes (%) | |||
| Bailey et al. (26) | III | — | — | — | — | −0.3 (1.0) to 0.00 (1.2) | — | — | No |
| Bailey et al. (9) | III | — | — | — | — | −1.6 (0.9) to −0.6 (1.4) | — | 25%↓ and 2%↓ > 4 mm | Yes |
| Brandtner et al. (20) | II | 5.7 (3.2) | 2.0 (0.9) | — | 2.5 (1.3) | — | 25% | — | No |
| Dolce et al. (18) | II | 7.5 (0.5) | 2.7 (0.1) | 3.7 (0.1) | — | — | 37% | — | No |
| Joss and Thüer (25) | III | −3.2 (4.0) | — | — | 2.2 (1.7) | −0.1 (1.0) | — | — | No |
| Proffit et al. (4) | II | — | — | — | — | — | — | 4%↓ and 8%↑ | Yes |
| Proffit et al. (23) | II | — | — | — | — | 1.0 (1.1) | — | 20% ↑ | Yes |
OJ, overjet; Δ, change; ↓, decrease; ↑, increase.
aClinically significant: changes > 2 mm during follow-up are considered clinically relevant, changes < 2 mm are not clinically relevant.
Occlusal parameters: OJ and OB
Table 1 reports the evolution of OJ after orthodontic and orthognathic treatment. For skeletal class II patients, an increase in OJ was seen in the studies of Proffit et al., Brandtner et al., and Dolce et al. at long-term follow-up (4, 18, 20, 23). However, only the two studies of Proffit et al. reported clinically significant increased OJ values between 2 and 4 mm, respectively, for 8% of skeletal class II patients treated by bimaxillary surgery and 20% of the young skeletal class II patients (<16-year-old females, <18-year-old males) who underwent mandibular advancement (4, 23). For skeletal class III patients, only Bailey et al. reported a clinically significant OJ relapse after bimaxillary surgery, with 2% of the patients showing a relapse of more than 4 mm (9).
The long-term changes in OB for skeletal class II and III patients were reported in eight studies (Table 2). Two studies showed a clinically significant increase in OB for skeletal class II patients at long-term follow-up (4, 18). Furthermore, Ding et al. reported OB changes in anterior open-bite patients who underwent bimaxillary surgery, with only 1 of the 10 patients showing a negative OB at mean follow-up of 15 years (21).
Overbite changes after combined orthodontics and orthognathic surgical treatment in class II and III patients during long-term follow-up.
| Reference | Skeletal class | Mean OB (mm ± SD) | OB relapse (between post-treatment and longest follow-up) | Clinically significanta | |||||
|---|---|---|---|---|---|---|---|---|---|
| Baseline | Post-treatment | 5 years | >5 years | Change (Δ mm ± SD) | Estimated mean change (%) | Patients with 2- to 4-mm changes (%) | |||
| Bailey et al. (26) | III | — | — | — | — | −0.2 (1.3) to 1.0 (0.6) | — | — | No |
| Bailey et al. (9) | III | — | — | — | — | 1.0 (1.7) to 2.1 (1.5) | — | — | Yes |
| Brandtner et al. (20) | II | 3.1 (3.2) | 2.2 (1.1) | — | 2.4 (1.2) | — | 9% | — | No |
| Ding et al. (21) | I, II, and III (open bite) | −3.2 (4.5) | 0.6 (3.5) | — | 1.5 (2.0) | — | 150% | — | No |
| Dolce et al. (18) | II | 4.2 (0.4) | 0.4 (0.2) | 2.4 (0.2) | — | — | 500% | — | Yes |
| Joss and Thüer (25) | III | 1.4 (2.7) | 2.7 (0.8) | — | — | −0.2 (1.2) | — | — | No |
| Proffit et al. (4) | II | — | — | — | — | — | — | 12% ↑ 4% ↓ | Yes |
| 4%↓ > 4 mm | |||||||||
| Proffit et al. (23) | II | — | — | — | — | 0.0 (1.4) | — | — | No |
| Reference | Skeletal class | Mean OB (mm ± SD) | OB relapse (between post-treatment and longest follow-up) | Clinically significanta | |||||
|---|---|---|---|---|---|---|---|---|---|
| Baseline | Post-treatment | 5 years | >5 years | Change (Δ mm ± SD) | Estimated mean change (%) | Patients with 2- to 4-mm changes (%) | |||
| Bailey et al. (26) | III | — | — | — | — | −0.2 (1.3) to 1.0 (0.6) | — | — | No |
| Bailey et al. (9) | III | — | — | — | — | 1.0 (1.7) to 2.1 (1.5) | — | — | Yes |
| Brandtner et al. (20) | II | 3.1 (3.2) | 2.2 (1.1) | — | 2.4 (1.2) | — | 9% | — | No |
| Ding et al. (21) | I, II, and III (open bite) | −3.2 (4.5) | 0.6 (3.5) | — | 1.5 (2.0) | — | 150% | — | No |
| Dolce et al. (18) | II | 4.2 (0.4) | 0.4 (0.2) | 2.4 (0.2) | — | — | 500% | — | Yes |
| Joss and Thüer (25) | III | 1.4 (2.7) | 2.7 (0.8) | — | — | −0.2 (1.2) | — | — | No |
| Proffit et al. (4) | II | — | — | — | — | — | — | 12% ↑ 4% ↓ | Yes |
| 4%↓ > 4 mm | |||||||||
| Proffit et al. (23) | II | — | — | — | — | 0.0 (1.4) | — | — | No |
OB, overbite; Δ, change; ↓, decrease; ↑, increase.
aClinically significant: changes > 2 mm during follow-up are considered clinically relevant, changes < 2 mm are not clinically relevant.
Overbite changes after combined orthodontics and orthognathic surgical treatment in class II and III patients during long-term follow-up.
| Reference | Skeletal class | Mean OB (mm ± SD) | OB relapse (between post-treatment and longest follow-up) | Clinically significanta | |||||
|---|---|---|---|---|---|---|---|---|---|
| Baseline | Post-treatment | 5 years | >5 years | Change (Δ mm ± SD) | Estimated mean change (%) | Patients with 2- to 4-mm changes (%) | |||
| Bailey et al. (26) | III | — | — | — | — | −0.2 (1.3) to 1.0 (0.6) | — | — | No |
| Bailey et al. (9) | III | — | — | — | — | 1.0 (1.7) to 2.1 (1.5) | — | — | Yes |
| Brandtner et al. (20) | II | 3.1 (3.2) | 2.2 (1.1) | — | 2.4 (1.2) | — | 9% | — | No |
| Ding et al. (21) | I, II, and III (open bite) | −3.2 (4.5) | 0.6 (3.5) | — | 1.5 (2.0) | — | 150% | — | No |
| Dolce et al. (18) | II | 4.2 (0.4) | 0.4 (0.2) | 2.4 (0.2) | — | — | 500% | — | Yes |
| Joss and Thüer (25) | III | 1.4 (2.7) | 2.7 (0.8) | — | — | −0.2 (1.2) | — | — | No |
| Proffit et al. (4) | II | — | — | — | — | — | — | 12% ↑ 4% ↓ | Yes |
| 4%↓ > 4 mm | |||||||||
| Proffit et al. (23) | II | — | — | — | — | 0.0 (1.4) | — | — | No |
| Reference | Skeletal class | Mean OB (mm ± SD) | OB relapse (between post-treatment and longest follow-up) | Clinically significanta | |||||
|---|---|---|---|---|---|---|---|---|---|
| Baseline | Post-treatment | 5 years | >5 years | Change (Δ mm ± SD) | Estimated mean change (%) | Patients with 2- to 4-mm changes (%) | |||
| Bailey et al. (26) | III | — | — | — | — | −0.2 (1.3) to 1.0 (0.6) | — | — | No |
| Bailey et al. (9) | III | — | — | — | — | 1.0 (1.7) to 2.1 (1.5) | — | — | Yes |
| Brandtner et al. (20) | II | 3.1 (3.2) | 2.2 (1.1) | — | 2.4 (1.2) | — | 9% | — | No |
| Ding et al. (21) | I, II, and III (open bite) | −3.2 (4.5) | 0.6 (3.5) | — | 1.5 (2.0) | — | 150% | — | No |
| Dolce et al. (18) | II | 4.2 (0.4) | 0.4 (0.2) | 2.4 (0.2) | — | — | 500% | — | Yes |
| Joss and Thüer (25) | III | 1.4 (2.7) | 2.7 (0.8) | — | — | −0.2 (1.2) | — | — | No |
| Proffit et al. (4) | II | — | — | — | — | — | — | 12% ↑ 4% ↓ | Yes |
| 4%↓ > 4 mm | |||||||||
| Proffit et al. (23) | II | — | — | — | — | 0.0 (1.4) | — | — | No |
OB, overbite; Δ, change; ↓, decrease; ↑, increase.
aClinically significant: changes > 2 mm during follow-up are considered clinically relevant, changes < 2 mm are not clinically relevant.
Dental changes: upper and lower incisor position (U1, L1)
The vertical and horizontal positional changes of the maxillary and mandibular incisors are shown in Tables 3 and 4. Following BSSO advancement, Dolce et al. found a transient anterior movement with vertical eruption for U1, whereas L1 showed an anterior movement followed by a posterior movement in the horizontal plane and superior movement in the vertical plane (18). The study of Proffit et al. reported a proclination of the lower incisors in skeletal class II patients who underwent bimaxillary surgery, resulting in a smaller increase in OJ than the decrease in mandibular length (4). Finally, for skeletal class II patients undergoing bimaxillary surgery with two-piece maxillary treatment, Brandtner et al. found a clinically significant decrease in the maxillary (40%) and mandibular incisor (26%) inclination at long-term follow-up (20).
Upper incisor (U1) changes after combined orthodontics and orthognathic surgical treatment in class II and III patients during long-term follow-up.
| Reference | Skeletal class | Axis | Mean U1 values (mm ± SD) | U1 relapse (between post-treatment and longest follow-up) | Clinically significanta | |||||
|---|---|---|---|---|---|---|---|---|---|---|
| Baseline | Post-treatment | 5 years | >5 years | Change(Δ mm ± SD) | Mean change(%) | Patients with 2- to 4-mm changes (%) | ||||
| Brandtner et al. (20) | II | Sagittal | –7.9 (6.25) | 9.5 (5.7) | — | −9.3 (5.7) | — | 12% | — | No |
| Vertical | −77.2 (5.1) | 77.1 (4.1) | — | −77.7 (3.8) | — | 1% | — | No | ||
| Dolce et al. (19) | II | Sagittal | — | — | — | — | 0 | — | — | N/A |
| Vertical | — | — | — | — | −0.6 (0.3) | — | — | N/A | ||
| Eggensperger et al. (24) | II | Sagittal | — | — | — | — | 1.1 (3.6) | — | — | No |
| Vertical | — | — | — | — | 0.9 (2.3) | — | — | No | ||
| Eggensperger et al. (24) | III | Sagittal | — | — | — | — | −0.2 (1.8) | — | — | No |
| Vertical | — | — | — | — | 0.8 (1.7) | — | — | No | ||
| Joss and Thüer (25) | III | Sagittal | — | — | — | — | 0.6 (2.8) | — | — | Yes |
| Vertical | — | — | — | — | 0.3 (1.5) | — | — | No | ||
| Proffit et al. (4) | II | Sagittal | — | — | — | — | — | — | 16% ←5%↑ | Yes |
| Vertical | — | — | — | — | — | — | 9%↓ | Yes | ||
| Reference | Skeletal class | Axis | Mean U1 values (mm ± SD) | U1 relapse (between post-treatment and longest follow-up) | Clinically significanta | |||||
|---|---|---|---|---|---|---|---|---|---|---|
| Baseline | Post-treatment | 5 years | >5 years | Change(Δ mm ± SD) | Mean change(%) | Patients with 2- to 4-mm changes (%) | ||||
| Brandtner et al. (20) | II | Sagittal | –7.9 (6.25) | 9.5 (5.7) | — | −9.3 (5.7) | — | 12% | — | No |
| Vertical | −77.2 (5.1) | 77.1 (4.1) | — | −77.7 (3.8) | — | 1% | — | No | ||
| Dolce et al. (19) | II | Sagittal | — | — | — | — | 0 | — | — | N/A |
| Vertical | — | — | — | — | −0.6 (0.3) | — | — | N/A | ||
| Eggensperger et al. (24) | II | Sagittal | — | — | — | — | 1.1 (3.6) | — | — | No |
| Vertical | — | — | — | — | 0.9 (2.3) | — | — | No | ||
| Eggensperger et al. (24) | III | Sagittal | — | — | — | — | −0.2 (1.8) | — | — | No |
| Vertical | — | — | — | — | 0.8 (1.7) | — | — | No | ||
| Joss and Thüer (25) | III | Sagittal | — | — | — | — | 0.6 (2.8) | — | — | Yes |
| Vertical | — | — | — | — | 0.3 (1.5) | — | — | No | ||
| Proffit et al. (4) | II | Sagittal | — | — | — | — | — | — | 16% ←5%↑ | Yes |
| Vertical | — | — | — | — | — | — | 9%↓ | Yes | ||
U1, upper incisor; N/A, not applicable; Δ, change; ↓, decrease; ←, posterior movement; →, anterior movement.
aClinically significant: changes > 2mm during follow-up are considered clinically relevant, changes < 2mm are not clinically relevant.
Upper incisor (U1) changes after combined orthodontics and orthognathic surgical treatment in class II and III patients during long-term follow-up.
| Reference | Skeletal class | Axis | Mean U1 values (mm ± SD) | U1 relapse (between post-treatment and longest follow-up) | Clinically significanta | |||||
|---|---|---|---|---|---|---|---|---|---|---|
| Baseline | Post-treatment | 5 years | >5 years | Change(Δ mm ± SD) | Mean change(%) | Patients with 2- to 4-mm changes (%) | ||||
| Brandtner et al. (20) | II | Sagittal | –7.9 (6.25) | 9.5 (5.7) | — | −9.3 (5.7) | — | 12% | — | No |
| Vertical | −77.2 (5.1) | 77.1 (4.1) | — | −77.7 (3.8) | — | 1% | — | No | ||
| Dolce et al. (19) | II | Sagittal | — | — | — | — | 0 | — | — | N/A |
| Vertical | — | — | — | — | −0.6 (0.3) | — | — | N/A | ||
| Eggensperger et al. (24) | II | Sagittal | — | — | — | — | 1.1 (3.6) | — | — | No |
| Vertical | — | — | — | — | 0.9 (2.3) | — | — | No | ||
| Eggensperger et al. (24) | III | Sagittal | — | — | — | — | −0.2 (1.8) | — | — | No |
| Vertical | — | — | — | — | 0.8 (1.7) | — | — | No | ||
| Joss and Thüer (25) | III | Sagittal | — | — | — | — | 0.6 (2.8) | — | — | Yes |
| Vertical | — | — | — | — | 0.3 (1.5) | — | — | No | ||
| Proffit et al. (4) | II | Sagittal | — | — | — | — | — | — | 16% ←5%↑ | Yes |
| Vertical | — | — | — | — | — | — | 9%↓ | Yes | ||
| Reference | Skeletal class | Axis | Mean U1 values (mm ± SD) | U1 relapse (between post-treatment and longest follow-up) | Clinically significanta | |||||
|---|---|---|---|---|---|---|---|---|---|---|
| Baseline | Post-treatment | 5 years | >5 years | Change(Δ mm ± SD) | Mean change(%) | Patients with 2- to 4-mm changes (%) | ||||
| Brandtner et al. (20) | II | Sagittal | –7.9 (6.25) | 9.5 (5.7) | — | −9.3 (5.7) | — | 12% | — | No |
| Vertical | −77.2 (5.1) | 77.1 (4.1) | — | −77.7 (3.8) | — | 1% | — | No | ||
| Dolce et al. (19) | II | Sagittal | — | — | — | — | 0 | — | — | N/A |
| Vertical | — | — | — | — | −0.6 (0.3) | — | — | N/A | ||
| Eggensperger et al. (24) | II | Sagittal | — | — | — | — | 1.1 (3.6) | — | — | No |
| Vertical | — | — | — | — | 0.9 (2.3) | — | — | No | ||
| Eggensperger et al. (24) | III | Sagittal | — | — | — | — | −0.2 (1.8) | — | — | No |
| Vertical | — | — | — | — | 0.8 (1.7) | — | — | No | ||
| Joss and Thüer (25) | III | Sagittal | — | — | — | — | 0.6 (2.8) | — | — | Yes |
| Vertical | — | — | — | — | 0.3 (1.5) | — | — | No | ||
| Proffit et al. (4) | II | Sagittal | — | — | — | — | — | — | 16% ←5%↑ | Yes |
| Vertical | — | — | — | — | — | — | 9%↓ | Yes | ||
U1, upper incisor; N/A, not applicable; Δ, change; ↓, decrease; ←, posterior movement; →, anterior movement.
aClinically significant: changes > 2mm during follow-up are considered clinically relevant, changes < 2mm are not clinically relevant.
Lower incisor (L1) changes after combined orthodontics and orthognathic surgical treatment in class II and III patients during long-term follow-up.
| Reference | Skeletal class | Axis | Mean L1 values (mm ± SD) | L1 relapse (between post-treatment and longest follow-up) | Clinically significanta | |||||
|---|---|---|---|---|---|---|---|---|---|---|
| Baseline | Post-treatment | 5 years | >5 years | Change (Δ mm ± SD) | Mean change (%) | Patients with 2- to 4-mm changes (%) | ||||
| Brandtner et al. (20) | II | Sagittal | −15.2 (10.4) | −12.3 (5.7) | — | −12.2 (5.7) | — | 1% | — | No |
| Vertical | −73.3 (5.4) | −74.7 (3.8) | — | −75.0 (4.2) | — | 0% | — | No | ||
| Dolce et al. (18) | II | Sagittal | — | — | — | — | 3.9 (3.3) | — | — | N/A |
| Vertical | — | — | — | — | −2.3 (3.1) | — | — | N/A | ||
| Dolce et al. (19) | II | Sagittal | 4.5 (2.5) to 5.0 (3.5) | 5.0 (2.5) to 5.5 (4.0) | 3.1 (3.3) to 4.6 (3.5) | — | — | 16 to 38% | — | N/A |
| Eggensperger et al. (24) | III | Sagittal | — | — | — | — | −0.3 (1.3) | — | — | No |
| Vertical | — | — | — | — | 1.8 (2.2) | — | — | Yes | ||
| Eggensperger et al. (22) | II | Sagittal | — | — | — | — | 0.5 (2.2) | — | — | Yes |
| Vertical | — | — | — | — | 0.2 (1.8) | — | — | No | ||
| Eggensperger et al. (22) | III | Sagittal | — | — | — | — | −0.3 (1.3) | — | — | No |
| Vertical | — | — | — | — | 1.8 (2.2) | — | — | Yes | ||
| Joss and Thüer (25) | III | Sagittal | — | — | — | — | 0.7 (2.9) | — | — | Yes |
| Vertical | — | — | — | — | 0.5 (1.5) | — | — | No | ||
| Proffit et al. (4) | II | Sagittal | — | — | — | — | — | — | 16% ← | Yes |
| 2.5% → | ||||||||||
| Vertical | — | — | — | — | — | — | 6%↓ 5%↑ | Yes | ||
| Reference | Skeletal class | Axis | Mean L1 values (mm ± SD) | L1 relapse (between post-treatment and longest follow-up) | Clinically significanta | |||||
|---|---|---|---|---|---|---|---|---|---|---|
| Baseline | Post-treatment | 5 years | >5 years | Change (Δ mm ± SD) | Mean change (%) | Patients with 2- to 4-mm changes (%) | ||||
| Brandtner et al. (20) | II | Sagittal | −15.2 (10.4) | −12.3 (5.7) | — | −12.2 (5.7) | — | 1% | — | No |
| Vertical | −73.3 (5.4) | −74.7 (3.8) | — | −75.0 (4.2) | — | 0% | — | No | ||
| Dolce et al. (18) | II | Sagittal | — | — | — | — | 3.9 (3.3) | — | — | N/A |
| Vertical | — | — | — | — | −2.3 (3.1) | — | — | N/A | ||
| Dolce et al. (19) | II | Sagittal | 4.5 (2.5) to 5.0 (3.5) | 5.0 (2.5) to 5.5 (4.0) | 3.1 (3.3) to 4.6 (3.5) | — | — | 16 to 38% | — | N/A |
| Eggensperger et al. (24) | III | Sagittal | — | — | — | — | −0.3 (1.3) | — | — | No |
| Vertical | — | — | — | — | 1.8 (2.2) | — | — | Yes | ||
| Eggensperger et al. (22) | II | Sagittal | — | — | — | — | 0.5 (2.2) | — | — | Yes |
| Vertical | — | — | — | — | 0.2 (1.8) | — | — | No | ||
| Eggensperger et al. (22) | III | Sagittal | — | — | — | — | −0.3 (1.3) | — | — | No |
| Vertical | — | — | — | — | 1.8 (2.2) | — | — | Yes | ||
| Joss and Thüer (25) | III | Sagittal | — | — | — | — | 0.7 (2.9) | — | — | Yes |
| Vertical | — | — | — | — | 0.5 (1.5) | — | — | No | ||
| Proffit et al. (4) | II | Sagittal | — | — | — | — | — | — | 16% ← | Yes |
| 2.5% → | ||||||||||
| Vertical | — | — | — | — | — | — | 6%↓ 5%↑ | Yes | ||
L1, lower incisor; Mnl: mandibular length; N/A, not applicable; Δ, change; ↓, decrease; ↑, increase; ←, posterior movement; →, anterior movement.
aClinically significant: changes > 2mm during follow-up are considered clinically relevant, changes < 2mm are not clinically relevant.
Lower incisor (L1) changes after combined orthodontics and orthognathic surgical treatment in class II and III patients during long-term follow-up.
| Reference | Skeletal class | Axis | Mean L1 values (mm ± SD) | L1 relapse (between post-treatment and longest follow-up) | Clinically significanta | |||||
|---|---|---|---|---|---|---|---|---|---|---|
| Baseline | Post-treatment | 5 years | >5 years | Change (Δ mm ± SD) | Mean change (%) | Patients with 2- to 4-mm changes (%) | ||||
| Brandtner et al. (20) | II | Sagittal | −15.2 (10.4) | −12.3 (5.7) | — | −12.2 (5.7) | — | 1% | — | No |
| Vertical | −73.3 (5.4) | −74.7 (3.8) | — | −75.0 (4.2) | — | 0% | — | No | ||
| Dolce et al. (18) | II | Sagittal | — | — | — | — | 3.9 (3.3) | — | — | N/A |
| Vertical | — | — | — | — | −2.3 (3.1) | — | — | N/A | ||
| Dolce et al. (19) | II | Sagittal | 4.5 (2.5) to 5.0 (3.5) | 5.0 (2.5) to 5.5 (4.0) | 3.1 (3.3) to 4.6 (3.5) | — | — | 16 to 38% | — | N/A |
| Eggensperger et al. (24) | III | Sagittal | — | — | — | — | −0.3 (1.3) | — | — | No |
| Vertical | — | — | — | — | 1.8 (2.2) | — | — | Yes | ||
| Eggensperger et al. (22) | II | Sagittal | — | — | — | — | 0.5 (2.2) | — | — | Yes |
| Vertical | — | — | — | — | 0.2 (1.8) | — | — | No | ||
| Eggensperger et al. (22) | III | Sagittal | — | — | — | — | −0.3 (1.3) | — | — | No |
| Vertical | — | — | — | — | 1.8 (2.2) | — | — | Yes | ||
| Joss and Thüer (25) | III | Sagittal | — | — | — | — | 0.7 (2.9) | — | — | Yes |
| Vertical | — | — | — | — | 0.5 (1.5) | — | — | No | ||
| Proffit et al. (4) | II | Sagittal | — | — | — | — | — | — | 16% ← | Yes |
| 2.5% → | ||||||||||
| Vertical | — | — | — | — | — | — | 6%↓ 5%↑ | Yes | ||
| Reference | Skeletal class | Axis | Mean L1 values (mm ± SD) | L1 relapse (between post-treatment and longest follow-up) | Clinically significanta | |||||
|---|---|---|---|---|---|---|---|---|---|---|
| Baseline | Post-treatment | 5 years | >5 years | Change (Δ mm ± SD) | Mean change (%) | Patients with 2- to 4-mm changes (%) | ||||
| Brandtner et al. (20) | II | Sagittal | −15.2 (10.4) | −12.3 (5.7) | — | −12.2 (5.7) | — | 1% | — | No |
| Vertical | −73.3 (5.4) | −74.7 (3.8) | — | −75.0 (4.2) | — | 0% | — | No | ||
| Dolce et al. (18) | II | Sagittal | — | — | — | — | 3.9 (3.3) | — | — | N/A |
| Vertical | — | — | — | — | −2.3 (3.1) | — | — | N/A | ||
| Dolce et al. (19) | II | Sagittal | 4.5 (2.5) to 5.0 (3.5) | 5.0 (2.5) to 5.5 (4.0) | 3.1 (3.3) to 4.6 (3.5) | — | — | 16 to 38% | — | N/A |
| Eggensperger et al. (24) | III | Sagittal | — | — | — | — | −0.3 (1.3) | — | — | No |
| Vertical | — | — | — | — | 1.8 (2.2) | — | — | Yes | ||
| Eggensperger et al. (22) | II | Sagittal | — | — | — | — | 0.5 (2.2) | — | — | Yes |
| Vertical | — | — | — | — | 0.2 (1.8) | — | — | No | ||
| Eggensperger et al. (22) | III | Sagittal | — | — | — | — | −0.3 (1.3) | — | — | No |
| Vertical | — | — | — | — | 1.8 (2.2) | — | — | Yes | ||
| Joss and Thüer (25) | III | Sagittal | — | — | — | — | 0.7 (2.9) | — | — | Yes |
| Vertical | — | — | — | — | 0.5 (1.5) | — | — | No | ||
| Proffit et al. (4) | II | Sagittal | — | — | — | — | — | — | 16% ← | Yes |
| 2.5% → | ||||||||||
| Vertical | — | — | — | — | — | — | 6%↓ 5%↑ | Yes | ||
L1, lower incisor; Mnl: mandibular length; N/A, not applicable; Δ, change; ↓, decrease; ↑, increase; ←, posterior movement; →, anterior movement.
aClinically significant: changes > 2mm during follow-up are considered clinically relevant, changes < 2mm are not clinically relevant.
Dentolabial outcome
Three studies reported long-term changes related to dentolabial outcomes (19, 22, 26) (Table 5). Bailey et al. reported the soft tissue changes for class III patients after maxillary advancement, mandibular setback, and bimaxillary surgery (26). All groups showed a decrease in maxillary and mandibular lip thickness at long-term follow-up. The maxillary advancement and bimaxillary surgery group showed a mean decrease in maxillary incisor display, whereas an increase in mandibular tooth display was seen after mandibular setback. Furthermore, Eggensperger et al. reported dentolabial changes for both skeletal class II and III patients, having, respectively, BSSO advancement and BSSO setback (22). After an initial forward movement at superior labial sulcus and labrale superius, all landmarks showed a posterior and inferior movement at long-term follow-up resulting in a thinner and longer upper lip. For the class II patients undergoing BSSO advancement, a posterior movement of labrale inferius and a reduction in thickness of the lower lip were found at long-term follow-up.
Dentolabial changes after combined orthodontics and orthognathic surgical treatment in class II and III patients during long-term follow-up.
| Reference | Skeletal class | Axis | Dentolabial outcome | Mean dentolabial values (mm ± SD) | Dentolabial relapse (between post-treatment and longest follow-up) | Clinically significanta | ||||
|---|---|---|---|---|---|---|---|---|---|---|
| Baseline | Post-treatment | 5 years | >5 years | Change (Δ mm ± SD) | Mean change (%) | |||||
| Bailey et al. (26) | III | Sagittal | U1-Ls | — | — | — | — | −0.8 (1.1) to −0.5 (1.3)a | — | No |
| L1-Li | — | — | — | — | −0.4 (1.2) | — | No | |||
| Vertical | U1-Ls | — | — | — | — | −0.8 (1.5) to −0.1(0.9) | — | No | ||
| L1-Li | — | — | — | — | 0.2 (2.0) to 1.3(1.7) | — | Yes | |||
| Dolce et al. (19) | II | Sagittal | Li | 6.5 (3.5) to 7.8 (3.7) | 3.5 (4.4) to 3.8 (3.5) | 1.5 (4.5) to 2.0 (5.5) | — | — | 47 to 57% | N/A |
| Eggensperger et al. (22) | II | Sagittal | Stmi | — | — | — | — | −1.2 (1.7) | — | Yes |
| Li | — | — | — | — | 0.7 (2.0) | — | Yes | |||
| Stms | — | — | — | — | −0.5 (2.5) | — | Yes | |||
| Ls | — | — | — | — | 0.4 (1.6) | — | No | |||
| Vertical | Stmi | — | — | — | — | 1.5 (1.9) | — | Yes | ||
| Li | — | — | — | — | −0.1 (2.4) | — | No | |||
| Stms | — | — | — | — | 0.7 (1.9) | — | No | |||
| Ls | — | — | — | — | −1.6 (2.6) | — | Yes | |||
| Eggensperger et al. (22) | III | Sagittal | Stmi | — | — | — | — | −0.1 (1.4) | — | No |
| Li | — | — | — | — | −1.1 (2.0) | — | Yes | |||
| Stms | — | — | — | — | −0.6 (1.5) | — | No | |||
| Ls | — | — | — | — | −0.3 (1.2) | — | No | |||
| Vertical | Stmi | — | — | — | — | 0.1 (1.6) | — | No | ||
| Li | — | — | — | — | 1.1 (2.6) | — | Yes | |||
| Stms | — | — | — | — | 1.1 (1.9) | — | Yes | |||
| Ls | — | — | — | — | 0.9 (0.9) | — | No | |||
| Reference | Skeletal class | Axis | Dentolabial outcome | Mean dentolabial values (mm ± SD) | Dentolabial relapse (between post-treatment and longest follow-up) | Clinically significanta | ||||
|---|---|---|---|---|---|---|---|---|---|---|
| Baseline | Post-treatment | 5 years | >5 years | Change (Δ mm ± SD) | Mean change (%) | |||||
| Bailey et al. (26) | III | Sagittal | U1-Ls | — | — | — | — | −0.8 (1.1) to −0.5 (1.3)a | — | No |
| L1-Li | — | — | — | — | −0.4 (1.2) | — | No | |||
| Vertical | U1-Ls | — | — | — | — | −0.8 (1.5) to −0.1(0.9) | — | No | ||
| L1-Li | — | — | — | — | 0.2 (2.0) to 1.3(1.7) | — | Yes | |||
| Dolce et al. (19) | II | Sagittal | Li | 6.5 (3.5) to 7.8 (3.7) | 3.5 (4.4) to 3.8 (3.5) | 1.5 (4.5) to 2.0 (5.5) | — | — | 47 to 57% | N/A |
| Eggensperger et al. (22) | II | Sagittal | Stmi | — | — | — | — | −1.2 (1.7) | — | Yes |
| Li | — | — | — | — | 0.7 (2.0) | — | Yes | |||
| Stms | — | — | — | — | −0.5 (2.5) | — | Yes | |||
| Ls | — | — | — | — | 0.4 (1.6) | — | No | |||
| Vertical | Stmi | — | — | — | — | 1.5 (1.9) | — | Yes | ||
| Li | — | — | — | — | −0.1 (2.4) | — | No | |||
| Stms | — | — | — | — | 0.7 (1.9) | — | No | |||
| Ls | — | — | — | — | −1.6 (2.6) | — | Yes | |||
| Eggensperger et al. (22) | III | Sagittal | Stmi | — | — | — | — | −0.1 (1.4) | — | No |
| Li | — | — | — | — | −1.1 (2.0) | — | Yes | |||
| Stms | — | — | — | — | −0.6 (1.5) | — | No | |||
| Ls | — | — | — | — | −0.3 (1.2) | — | No | |||
| Vertical | Stmi | — | — | — | — | 0.1 (1.6) | — | No | ||
| Li | — | — | — | — | 1.1 (2.6) | — | Yes | |||
| Stms | — | — | — | — | 1.1 (1.9) | — | Yes | |||
| Ls | — | — | — | — | 0.9 (0.9) | — | No | |||
Li, labrale inferius; Ls, labrale superius; U1, upper incisor; Li, lower incisor; Stmi, stomion inferius; Stms, stomion superius; N/A, not applicable; Δ, change.
aClinically significant: changes > 2 mm during follow-up are considered clinically relevant, changes < 2 mm are not clinically relevant.
Dentolabial changes after combined orthodontics and orthognathic surgical treatment in class II and III patients during long-term follow-up.
| Reference | Skeletal class | Axis | Dentolabial outcome | Mean dentolabial values (mm ± SD) | Dentolabial relapse (between post-treatment and longest follow-up) | Clinically significanta | ||||
|---|---|---|---|---|---|---|---|---|---|---|
| Baseline | Post-treatment | 5 years | >5 years | Change (Δ mm ± SD) | Mean change (%) | |||||
| Bailey et al. (26) | III | Sagittal | U1-Ls | — | — | — | — | −0.8 (1.1) to −0.5 (1.3)a | — | No |
| L1-Li | — | — | — | — | −0.4 (1.2) | — | No | |||
| Vertical | U1-Ls | — | — | — | — | −0.8 (1.5) to −0.1(0.9) | — | No | ||
| L1-Li | — | — | — | — | 0.2 (2.0) to 1.3(1.7) | — | Yes | |||
| Dolce et al. (19) | II | Sagittal | Li | 6.5 (3.5) to 7.8 (3.7) | 3.5 (4.4) to 3.8 (3.5) | 1.5 (4.5) to 2.0 (5.5) | — | — | 47 to 57% | N/A |
| Eggensperger et al. (22) | II | Sagittal | Stmi | — | — | — | — | −1.2 (1.7) | — | Yes |
| Li | — | — | — | — | 0.7 (2.0) | — | Yes | |||
| Stms | — | — | — | — | −0.5 (2.5) | — | Yes | |||
| Ls | — | — | — | — | 0.4 (1.6) | — | No | |||
| Vertical | Stmi | — | — | — | — | 1.5 (1.9) | — | Yes | ||
| Li | — | — | — | — | −0.1 (2.4) | — | No | |||
| Stms | — | — | — | — | 0.7 (1.9) | — | No | |||
| Ls | — | — | — | — | −1.6 (2.6) | — | Yes | |||
| Eggensperger et al. (22) | III | Sagittal | Stmi | — | — | — | — | −0.1 (1.4) | — | No |
| Li | — | — | — | — | −1.1 (2.0) | — | Yes | |||
| Stms | — | — | — | — | −0.6 (1.5) | — | No | |||
| Ls | — | — | — | — | −0.3 (1.2) | — | No | |||
| Vertical | Stmi | — | — | — | — | 0.1 (1.6) | — | No | ||
| Li | — | — | — | — | 1.1 (2.6) | — | Yes | |||
| Stms | — | — | — | — | 1.1 (1.9) | — | Yes | |||
| Ls | — | — | — | — | 0.9 (0.9) | — | No | |||
| Reference | Skeletal class | Axis | Dentolabial outcome | Mean dentolabial values (mm ± SD) | Dentolabial relapse (between post-treatment and longest follow-up) | Clinically significanta | ||||
|---|---|---|---|---|---|---|---|---|---|---|
| Baseline | Post-treatment | 5 years | >5 years | Change (Δ mm ± SD) | Mean change (%) | |||||
| Bailey et al. (26) | III | Sagittal | U1-Ls | — | — | — | — | −0.8 (1.1) to −0.5 (1.3)a | — | No |
| L1-Li | — | — | — | — | −0.4 (1.2) | — | No | |||
| Vertical | U1-Ls | — | — | — | — | −0.8 (1.5) to −0.1(0.9) | — | No | ||
| L1-Li | — | — | — | — | 0.2 (2.0) to 1.3(1.7) | — | Yes | |||
| Dolce et al. (19) | II | Sagittal | Li | 6.5 (3.5) to 7.8 (3.7) | 3.5 (4.4) to 3.8 (3.5) | 1.5 (4.5) to 2.0 (5.5) | — | — | 47 to 57% | N/A |
| Eggensperger et al. (22) | II | Sagittal | Stmi | — | — | — | — | −1.2 (1.7) | — | Yes |
| Li | — | — | — | — | 0.7 (2.0) | — | Yes | |||
| Stms | — | — | — | — | −0.5 (2.5) | — | Yes | |||
| Ls | — | — | — | — | 0.4 (1.6) | — | No | |||
| Vertical | Stmi | — | — | — | — | 1.5 (1.9) | — | Yes | ||
| Li | — | — | — | — | −0.1 (2.4) | — | No | |||
| Stms | — | — | — | — | 0.7 (1.9) | — | No | |||
| Ls | — | — | — | — | −1.6 (2.6) | — | Yes | |||
| Eggensperger et al. (22) | III | Sagittal | Stmi | — | — | — | — | −0.1 (1.4) | — | No |
| Li | — | — | — | — | −1.1 (2.0) | — | Yes | |||
| Stms | — | — | — | — | −0.6 (1.5) | — | No | |||
| Ls | — | — | — | — | −0.3 (1.2) | — | No | |||
| Vertical | Stmi | — | — | — | — | 0.1 (1.6) | — | No | ||
| Li | — | — | — | — | 1.1 (2.6) | — | Yes | |||
| Stms | — | — | — | — | 1.1 (1.9) | — | Yes | |||
| Ls | — | — | — | — | 0.9 (0.9) | — | No | |||
Li, labrale inferius; Ls, labrale superius; U1, upper incisor; Li, lower incisor; Stmi, stomion inferius; Stms, stomion superius; N/A, not applicable; Δ, change.
aClinically significant: changes > 2 mm during follow-up are considered clinically relevant, changes < 2 mm are not clinically relevant.
Quality assessment
Supplementary Tables 3 and 4 present the risk of bias assessment for the included studies. For most studies, a serious (4, 20, 21, 23, 24) or moderate (9, 22, 25, 26) overall risk of bias was observed, as they were judged to be at serious or moderate risk in at least one domain. The risk was considered low for bias in measurement of interventions, bias due to departures from intended interventions, and bias due to missing data. Randomization was only performed in two studies; these studies showed some concerns for the overall risk of bias (18, 19). According to GRADE, the quality of evidence was found to be moderate to low, as most of the studies were observational retrospective studies and there was a lack of blinding in the two RCTs.
Discussion
This systematic review aimed to evaluate dental and dentolabial changes after combined orthodontic and orthognathic surgical treatment during long-term follow-up. An attempt was made to include high-quality evidence studies, nevertheless only two RCTs and nine retrospective studies were finally selected with a postoperative follow-up period ranging from 5 to 15 years. A dental or skeletal relapse of ≥2 mm at postoperative follow-up is considered clinically significant (4). An understanding of stability following combined orthodontic-orthognathic treatment is important in order to achieve successful long-term correction of dentoskeletal discrepancies.
A wide variation in post-treatment relapse was found after combined orthodontic and orthognathic treatment. In general, OJ tended to increase in skeletal class II and decrease in skeletal class III patients over time, independent of the type of osteotomy or direction of movement performed. Following skeletal relapse, adaptive changes in the dentition were often seen, resulting in dental compensation. The study of Proffit et al. suggested a decrease in mandibular length related to condylar remodelling for skeletal class II patients following bimaxillary surgery (4). However, fewer than half of the patients demonstrated an increase in OJ at long-term follow-up because of lower incisor proclination (4). Brandtner et al. evaluated dental outcomes based on dental cast assessment in class II patients undergoing two-piece Le Fort and BSSO advancement (20). In patients with low registered maxillary expansion values, better sagittal stability was reported based on correct transverse width and teeth angulation.
The treatment of anterior open bite is often considered difficult and less predictable. Vertical relapse may occur because of various factors such as tongue size or posture, an unfavourable growth pattern, orofacial musculature, and condylar resorption (27). In the study of Ding et al., the sagittal and vertical discrepancies in skeletal anterior open-bite patients were corrected by bimaxillary surgery, resulting in a good occlusion with a relatively good tongue position (21). Despite moderate skeletal relapse at 15-year follow-up, the OB remained stable because of further compensatory eruption of maxillary and mandibular incisors. Results were comparable with those of Proffit et al., reporting a compensatory eruption of the anterior teeth in long-face patients with open bite, who experienced a downward movement of the maxilla following superior maxillary repositioning (4).
Dentolabial outcomes were only reported by three articles, and they represented measurements directly related to anterior teeth and lip position (19, 22, 26). Following surgery, maxillary and mandibular incisor display variations depend on their descending movement and thinning of the lips. These changes correspond to the normal ageing process and results were not clinically significant after long-term follow-up (26).
Most of the included studies were characterized by a high risk of bias with the quality of evidence limited due to retrospective design and small sample size. Furthermore, none of the included studies evaluated dental changes comparing immediate- and long-term postoperative outcomes utilizing 3D imaging (28, 29). Meta-analysis was not possible due to considerable variation among the included studies in relation to study design and assessment methodology. A further limitation of this review was that only English articles were included. On the other hand, the length of follow-up and detailed review of the dental changes were considered as strengths of this article as there is a lack of reviews focussing on long-term follow-up.
It is highly desirable that future prospective research on this topic should be carried out with a larger sample size utilizing 3D imaging modalities (CBCT or CT) to better assess relapse and stability in the long run. Furthermore, results should be presented in a standardized manner in order to enable comparison and draw accurate conclusions related to dental stability. Finally, it is suggested that other outcomes should also be considered such as periodontal measurements, root resorption, aesthetics, and patient satisfaction in order to evaluate benefit and stability of orthognathic surgery.
Conclusion
Current evidence suggests variability of dental and dentolabial changes in both skeletal class II and III patients at long-term follow-up. A high level of bias in the retrospective studies demonstrates the need to develop well-designed studies with CBCT or CT imaging and to strive for clinical guidance notes in relation to long-term follow-up, before final conclusions can be drawn.
Funding
No funding was available.
Conflicts of interest
None declared.
References
