Volumetric Analysis of Fat Injection by Computerized Tomography in Orthognathic Surgery: Preliminary Report on a Novel Volumetric Analysis Process for the Quantification of Aesthetic Results

Impact of orthognathic surgery on the cheek area using the Barcelona line

A facial appearance of premature aging due to poor bone support of the soft tissues is frequently found in patients with midface hypoplasia. This study was performed to evaluate the changes in the soft tissues of the cheek area in patients subjected to bimaxillary orthognathic surgery. The cheek line angle and length of 27 consecutive patients who underwent bimaxillary surgery, were measured on cone beam computed tomography scans obtained before surgery and at 1 and 12 months after surgery using 3D software. Changes between time-points were analyzed. Bimaxillary surgery was virtually planned in all patients using the Barcelona line protocol. The results showed a mean decrease in cheek angle of 5 ± 5° (P < 0.001). This decrease was reflected in a more anterior-projected cheek and was related to forward movement of the upper and lower incisors (x-axis) (r = -0.469, P = 0.014 and r = -0.440, P = 0.021, respectively). There was 3D stability of the hard and soft tissue changes at the 1-year postoperative follow-up. The results indicate that bimaxillary surgery performed following the Barcelona line as a planning reference could improve midfacial soft tissue support by means of a more anterior-projected cheek.

Modified Le Fort I Arc Osteotomy Combined With Autologous Bone Grafts to Improve Midface Hypoplasia Combined With Skeletal Class III Malocclusion: A Technical Note

Midface hypoplasia sometimes appears in patients with skeletal class III malocclusion in the Asian population, often requires additional surgical treatments. The technical note is intended to introduce a modified Le Fort I arc osteotomy combined with autologous bone grafts harvested from proximal segments after bilateral sagittal split ramus osteotomy to improve the profile for skeletal class III malocclusion patients with midface hypoplasia. The benefit of the modified technology is that the size and position of the arc can be adjusted according to the severity of the deformity to suit different patients. In addition, the application of autologous bone grafts increased the extra height of osteotomy line and enhanced the surgical effect, and maintained bone consolidation. More importantly, the osteotomy line of the modified Le Fort I arc osteotomy can be easily designed and this modification will not cause additional injuries. Therefore, we believe that for skeletal class III malocclusion patients with midface hypoplasia in Asia modified Le Fort I arc osteotomy combined with autologous bone grafts will be an efficient surgical method to improve midface hypoplasia.

Three-dimensional Quantitative Standards for Assessing Outcomes of Facial Lipotransfer: A Review

BACKGROUND

Reliable quantitative data are required to address the unpredictability of facial autologous fat grafting (AFG). Facial evaluation by 3D scanning technology is getting popular. However, this process lacks unified standards and the reliability assessments. This study aimed to summarize a set of standards to improve the 3D quantified reliability of AFG outcomes.

METHODS

A systematic review was used to collect the differences in and limitations of 3D assessments and analyze the effect of the quantification process on the AFG outcomes. Healthy subjects undergoing only one facial structural AFG and 3D assessments were included. The revealed specific issues guided the subsequent narrative review that involves 3D measurement and fat volume retention rate (FVRR) analysis. Criteria were formulated based on the narrative review.

RESULTS

The systematic review revealed the quantitative process to be operator-dependent. The intra-group FVRR in the postoperative 11+ month group varied significantly (P=.03). The review identified a set of 3D measurement standards, including two optimal software products, two necessary steps for preprocessing, and four testing criteria. We proposed a new calculation formula and parameter and recommended a segmental area analysis for assessing the outcomes of full-face fat grafting.

CONCLUSIONS

As far as the 3D evaluation of AFG outcomes is concerned, this is the first study to comprehensively analyze the process and set quantitative criteria. These standards would not only guide future research more reliably, but also provide fresh insight into the review of the past research. 3D measurement standards also apply to all face-related studies requiring 3D registration.

LEVEL OF EVIDENCE III

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Computer guided maxillo-malar piezoelectric osteotomies for midface augmentation

PURPOSE

Despite maxillo-malar osteotomies having been discarded in the most recent literature, in the setting of orthognathic surgery they provide several advantages for middle third augmentation. This paper reintroduces maxillo-malar osteotomies as an effective method to increase volume of midfacial region in combination with contemporary technology, including piezosurgery, virtual surgical planning, and navigation.

MATERIAL AND METHODS

Eighteen patients with midface hypoplasia were included in this study and underwent orthognathic surgery with maxillo-malar osteotomies. All patients underwent the same workflow: virtual design of maxillo-malar osteotomies, surgery with navigation-assisted piezoelectric osteotomies, and computerized morphometric analysis.

RESULTS

Simulated maxillo-malar osteotomies were successfully replicated in the operating room, as shown by accuracy evaluation performed using three-dimensional analysis. In long-term follow-up period, no permanent complications were assessed. Superimposition between postoperative and preoperative CBCTs revealed that the soft tissue area influenced by the underlying skeletal movement was comparable for all cases.

CONCLUSIONS

Virtual surgical planning, navigation, and piezosurgery are today indispensable tools to perform maxillo-malar osteotomies safely and accurately. We suggest incorporating such osteotomies in the surgeon's armamentarium for patients with severe midfacial hypoplasia as they offer an integrated solution to restore functionality and aesthetics.

Orthodontics Surgical Assistance (Piezosurgery®): Experimental Evidence According to Clinical Results

Orthodontic tooth movement (OTM) is based on intermitted or continuous forces applied to teeth, changing the mechanical loading of the system and arousing a cellular response that leads to bone adaptation. The traditional orthodontic movement causes a remodeling of the alveolar bone and changes in the periodontal structures that lead to tooth movement. The use of a piezoelectric instrument in orthodontic surgery has already shown great advantages. The purpose of this study is to rank the behavior of inflammatory mediators in accelerating orthodontic tooth movement. Ten patients with malocclusion underwent orthodontic surgical treatment, which included a first stage of surgically guided orthodontic movement (monocortical tooth dislocation and ligament distraction, MTDLD) to accelerate orthodontic movements. In all cases, corticotomy was performed by Piezosurgery. Bone and dental biopsy was executed to evaluate changes in the cytokines IL-1beta, TNF-alpha and IL-2 in different time intervals (1, 2, 7, 14 and 28 days). The molecular mediators are IL-1 beta, TNF-alpha and IL-2. Immediately after the surgical procedure there was a mild expression of the three molecular markers, while the assertion of IL-1 beta and TNF-alpha reached the maximum value after 24 h and 48 h, indicating a strong activation of the treated tissues. The Piezosurgery® surgical technique induces an evident stress in short times, within 24–48 h from the treatment, but it decreases significantly during the follow-up.

Clinical and radiographic features of facial cosmetic materials: A systematic review

Purpose

The aim of this study was to systematically screen the literature for studies reporting cosmetic material in the oral and maxillofacial complex to shed light on the types of cosmetic materials, their radiographic appearance, and possible complications.

Materials and Methods

Five electronic databases were reviewed for eligible studies. The general search terms were “cosmetic,” “filler,” “face,” and “radiograph.” Demographics, material types, clinical and radiographic presentation, and complications were recorded.

Results

Thirty-one studies with 53 cases met the inclusion criteria. The mean age was 52.6±15.4 years with a 4 : 3 female-to-male ratio. The most common material was calcium hydroxyapatite (CaHa) (n=14, 26.4%), found incidentally. The materials were generally located within the upper cheek and zygoma (n=35, 66.0%), radiographically well-defined (n=44, 83%), and had no effects on the surrounding structures (n=27, 50.9%). The internal structure was radiopaque (calcification, hyperdensity) for gold wires, CaHa, bone implants, and secondary calcification or ossification. Outdated cosmetic materials or non-conservative techniques were infiltrative, had effects on the surrounding structures, and presented with clinical signs, symptoms, or complications.

Conclusion

Conventional radiography, cone-beam computed tomography, and multi-detector computed tomography are useful to differentiate several cosmetic materials. Their magnetic resonance imaging appearance was highly variable. The infrequent inclusion of cosmetic materials in the differential diagnosis implies that medical and dental specialists may be unfamiliar with the radiographic appearance of these materials in the face.

Refining Orthognathic Surgery Results by Synchronous Cheek Fat Compartment Augmentation with Fat Grafting in Adult Females with Class III Skeletal Profiles

SUMMARY

Patients with maxillomandibular disharmony may present with a flat to concave midface. The effects of orthognathic surgery concomitant with midface fat grafting on facial appearance and midface volumetric and positional change have not formally been assessed to date. The authors' approach for synchronous orthognathic surgery and fat grafting is described and evaluated. Adult female patients (n = 20) who underwent synchronous two-jaw orthognathic surgery and cheek-specific fat grafting (1.9 ± 0.6 cm3 per side) for correction of skeletal class III deformity and anteromedial cheek deficiency were prospectively included. Preoperative and postoperative photographs were appraised by 42 blinded raters using facial appearance scales for beauty, attractiveness, and pleasantness parameters. The three-dimensional midface soft-tissue volume change and postoperative cheek mass position were computed. Facial imaging data from gender-, ethnic-, and facial pattern-matched adult patients (n = 20) who underwent isolated two-jaw orthognathic surgery (n = 20) were included for comparison. The three-dimensional facial norms database-derived cheek mass position information (2.19 ± 1.31mm) was also adopted for analysis. Patients treated with the synchronous procedure had significantly (p < 0.001) increased facial appearance-related perception change for beauty (2.9 ± 1.6), attractiveness (2.8 ± 1.8), and pleasantness (3.0 ± 1.5) parameters, three-dimensional midface volume change (1.8 ± 0.5 cm3), and postoperative cheek mass position (2.16 ± 0.47 mm) in comparison with those treated with the isolated procedure (2.0 ± 1.5, 1.9 ± 1.6, 2.3 ± 1.6, 0.6 ± 0.2 cm3, and 1.84 ± 0.43 mm, respectively). Healthy female individuals had similar and larger cheek mass position than patients treated with synchronous (p > 0.05) and isolated (p < 0.001) procedures, respectively. Synchronous orthognathic surgery and check-specific fat grafting resulted in superior enhancement of facial appearance and midface volume and position compared with isolated orthognathic surgery.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, III.

Volume Retention After Facial Fat Grafting and Relevant Factors: A Systematic Review and Meta-analysis

BACKGROUND

Autologous fat grafting is common in facial reconstructive and cosmetic surgeries; the most important drawbacks are the high absorption rate and unpredictable volume retention rate. Surgeons usually make clinical judgements based on their own experience. Therefore, this study aimed to systematically and quantitatively review the volume retention rate of facial autologous fat grafting and analyse the relevant influencing factors.

METHODS

A systematic literature review was performed using the Medline, EMBASE, Cochrane Library, and Web of Science databases in October 2019 for articles that reported objectively measured volume retention rates of facial fat grafting. Patient characteristics, fat graft volumetric data, and complications were collected. A meta-analysis using a random-effects model was conducted to pool the estimated fat retention rate. Relevant factors were analysed and reviewed on the basis of subgroups.

RESULTS

We included 27 studies involving 1011 patients with facial fat grafting. The volume retention rate varied from 26 to 83%, with a mean follow-up of 3-24 months. The overall pooled retention rate was 47% (95% CI 41-53%). The volume measurement method significantly influenced the reported retention rate. A trend towards better retention was found for secondary fat grafting procedures and patients with congenital deformities. Only 2.8% of all patients had complications.

CONCLUSION

The exact percentage of facial fat grafts retained is currently unpredictable; the reported rate varies with different estimation methods. This review analysed studies that provided objectively measured volume retention rates, the pooled average percentage of facial fat graft retention (47%, 95% CI 41-53%), and relevant factors.

LEVEL OF EVIDENCE III

This journal requires that authors assign a level of evidence to each article. For a full description of these evidence-based medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Aesthetic Dentistry, How You Say and How You See: A 500-People Survey on Digital Preview and Color Perception

Purpose

Digital technologies have improved ways to perform aesthetic dentistry in the last few years. The aims of this survey were to investigate the most preferred way to preview the result of an aesthetic dental rehabilitation among a population of dental professionals and laypeople and to compare aesthetic standards of the general population and dentists in terms of the color of teeth for aesthetic dental rehabilitations.

Patients and Methods

A questionnaire was sent to the subjects (dentists and laypeople) during a 1-year period and, together with their demographic data, different ways to preview the result of an aesthetic rehabilitation were submitted, such as digital smile design, dental wax-up and oral explanation. Furthermore, an additional section of the questionnaire investigated the most suitable color for an aesthetic rehabilitation based on the colors of the VITA Scale. Results were statistically analyzed (with Chi-square of independence and Mann–Whitney U-test) highlighting differences of answers based on age groups, educational attainment, gender, and belonging or not to the dental field.

Results

Findings showed that digital smile design (digital preview) is a high-appreciated method for previewing and communicating with patients both by dental professionals and laypeople. Furthermore, lighter colors were found to be more valued by laypeople and significant differences were highlighted between the two populations assessed.

Conclusion

It seems to be viable to use digital preview for dentists and laypeople to improve previewing and communicating ways. It might be advisable to better motivate patients in recognizing aesthetical features and to raise their awareness in preferring more mimetic aesthetic results. Great opportunities are opened up by digital smile design in teaching, learning, and routine practice.