The necessity of pterygomaxillary disjunction in surgically assisted rapid maxillary expansion: A short-term, double-blind, historical controlled clinical trial

Three-dimensional assessment of the maxilla after modified surgically assisted rapid expansion: a retrospective study

OBJECTIVE

This retrospective study aims to assess the three-dimensional dentoskeletal effects and median palatal suture opening pattern in patients undergoing modified surgically assisted maxillary rapid expansion (SARME) without pterygoid plate detachment.

METHODS

Twenty-eight patients submitted to modified SARME between 2009 and 2016 were retrospectively evaluated through cone-beam computed tomography (CBCT). Dental and skeletal measurements were taken at three different operative periods (before the expansion - T0; at the end of the activation of the Hyrax device - T1; and six months after the immobilization of the device - T2). Statistical analyses, including ANOVA and Pearson's correlation coefficient, were performed using SPSS software.

RESULTS

SARME demonstrated significant transverse maxillary expansion (with an average of 6.05 mm) with a greater impact in the anterior region. Dental measurements, including canine and molar distances, exhibited significant changes over the operative periods. Bone measurements (ANS and PNS) presented small but significant alterations, including a slight inferior displacement of ANS during device activation. The nasal floor width increased, followed by a width reduction after immobilization. The median palatal suture predominantly exhibited a Type II (V-shaped) opening.

CONCLUSION

The modified SARME presented a transversal direction increase and a super-lower skeletal displacement, with the anterior region being more affected than the posterior region. There was no change in the anteroposterior direction of the maxilla. Additionally, there was an increase in the linear dental measurements and a decrease in the angular measurement, with a positive correlation between the amount of posterior bone expansion and molar expansion as a result of the treatment in the analyzed period.

Effects of different expansion appliances and surgical incisions on maxillary expansion: A finite element analysis

PURPOSE

This study aims to assess the impact of different surgical techniques and three expansion appliances on maxillary expansion in adults using finite element analysis (FEA), with a focus on maxillary displacement and stress on surrounding structures.

METHODS

Seven different FEA models were created to compare different surgical techniques and three different expansion appliances. Model I represented a bone-supported appliance without surgical assistance. Model II, Model III, and Model IV were surgically assisted rapid palatal expansion (SARPE) models without pterygomaxillary suture disjunction (PMD). Model V, Model VI, and Model VII were SARPE models with PMD.

RESULTS

The largest displacement at the anterior nasal spine (ANS) was recorded for Model II (2.95 mm). For the posterior nasal spine (PNS), the highest displacement was observed in Models V, VI, VII (2.50 mm), with the lowest in Model III (0.79 mm). Stress analysis revealed the highest stress in Model I, with models featuring PMD displaying nearly zero stress at all anatomical points, highlighting distinct expansion patterns and stress distributions between models with and without PMD.

CONCLUSION

SARPE models with PMD demonstrated a parallel expansion of the maxilla with minimal stress, while the miniscrew assisted rapid maxillary expansion (MARPE) model displayed transverse rotation. SARPE models without PMD exhibited a V-shaped expansion pattern. SARPE models with PMD represent an optimal approach for achieving uniform expansion and minimizing stress, with stress levels nearly negligible at all anatomical points in models with PMD.

Evaluation of Treatment Protocols in Surgically Assisted Rapid Maxillary Expansion by Finite Element Analysis

Background and Objectives: Transverse maxillary deficiency is an important maxillary anomaly that is very common in society and remains current in orthodontics. The maxillary expansion has been used in treatment for a long time. While maxillary expansion can be performed with rapid maxillary expansion in young adults, it is performed with surgically assisted rapid maxillary expansion (SARME) in individuals who have reached skeletal maturity. No consensus has been reached on the most successful surgical technique or the ideal appliance for treating transverse maxillary deficiency. Accordingly, we aimed to evaluate various surgical techniques and orthodontic appliances for treating transverse maxillary deficiency using the finite element method (FEM) to identify the treatment protocol that minimizes stress on the maxillary bone and teeth. Materials and Methods: On the virtual models obtained from the cone beam computed tomography of a patient, two different incisions (the pterygomaxillary junction is separated and not separated) were made and combined using three different orthodontic appliances (tooth, bone, and hybrid assisted). Then, stresses over the maxillary bone and maxillary teeth were calculated by FEM. Results: Our results showed that when the pterygomaxillary plates were separated, fewer stresses were observed on the bone and teeth. Although hybrid-supported appliances created less stress on the teeth than tooth-supported appliances and no difference was found between bone-supported appliances, it was found that hybrid-supported appliances created less stress on the bone than the other appliances. Conclusions: The separation of the pterygomaxillary junction in the SARME operation and the use of a bone-supported or hybrid-supported appliance would place less stress on the bone and teeth.

The effects of pterygomaxillary disjunction in surgically assisted rapid maxillary expansion: A systematic review and meta-analysis

OBJECTIVE

This study aims to assess the expansive effects of pterygomaxillary disjunction (PMD) in surgically assisted rapid maxillary expansion (SARME) surgery using a meta-analysis approach.

MATERIALS AND METHODS

The study conducted a comprehensive literature search across five databases: PubMed, Scopus, Medline, Embase, and Cochrane, adhering to the PRISMA 2020 guidelines. Dental alterations were assessed using either cone-beam computed tomography (CBCT) or dental casts, while skeletal changes were exclusively measured from CBCT scans. We analysed the dentoskeletal changes between PMD +/- groups and conducted a within-group comparison. The primary focus of the results was on the mean differences observed in pre- and post-operative measurements.

RESULTS

Dental expansion was larger in the PMD+ group but not statistically significant. Skeletal expansion showed a significantly larger expansion in the posterior region in the PMD+ group (P = .033). Without PMD, anterior palatal expansion was significantly larger (P = .03), and the buccal tipping of posterior teeth was also significantly larger (P = .011) to achieve acceptable dental expansion outcomes.

CONCLUSIONS

Both PMD +/- groups of SARME surgery can achieve satisfactory dental expansion outcomes. However, bone expansion and tooth inclination are also important factors that influence orthodontic treatment and post-expansion stability. By reducing the bony resistance with PMD, larger posterior palatal expansion and more parallel bony expansion are observed. In contrast, without PMD, there is smaller palatal expansion and greater tooth inclination in the posterior region. This could potentially lead to compromised periodontal conditions following expansion.

Can different osteotomies have an influence on surgically assisted rapid maxillary expansion? A systematic review

The purpose of this study was to systematically review the randomized and non-randomized clinical trials (RCT; nRCT) concerning the different available osteotomies for surgically assisted rapid maxillary expansion (SARME): pterygomaxillary disjunction (SARME + PD vs SARME-PD) and segmental Le Fort I osteotomy (2-piece vs 3-piece). Outcomes focused on skeletal, dental, upper airway changes, complications, and relapse. Two authors investigated five databases (PubMed, Cochrane Library, Google Scholar, Scopus, Web of Science) until August 2023. The Cochrane Collaboration Tool and the Newcastle-Ottawa scale were used for the quality assessment of the included RCTs and nRCTs, respectively. A total of 554 articles were retrieved and after duplicates removing and full-text reading, 40 studies were included. Two RCTs showed a low risk of bias, one an unclear risk and one a high risk. Among the non-RCTs, 15 studies showed a good quality, while 21 exhibited a fair quality score. SARME + PD resulted in more homogeneous posterior bone expansion, with minimal dental effects. No difference between 2-piece and 3-piece in asymmetric expansion was observed, although 3SO showed 1-2 mm of more transverse increase. The oropharynx minimum cross-sectional area, the nasopharynx and the oropharynx volume were greater in SARME + PD. Both dental and bone relapse can occur but no differences between the groups were observed. All osteotomies guaranteed a correction of transverse maxillary deficiency. Lower side effects were described in SARME + PD. Two-piece and 3-piece segmental Le Fort I osteotomies did not show any differences in the symmetry and amount of expansion.

Effects of different distractor positions on the formation of expansion, stress and displacement patterns in surgically assisted rapid maxillary expansion without pterygomaxillary disjunction: a finite element analysis study

Skeletal orthopedic expansion of maxilla is accepted as a reliable method for the treatment of transverse maxillar deficiency in growing patients. The aim of the study was to evaluate the effects of different palatal distractor positions on the expansion, stress and displacement patterns of the structures of craniofacial complex in surgical assisted rapid maxillary expansion without pterygomaxillary disjunction (PTMD) with the help of finite element analysis(FEA). Four facial skeleton models with different distractor positions (first premolar, second premolar, first molar, second molar regions) were created. In all finite element models median and lateral osteotomies were performed, without PTMD. Stress distribution was evaluated after 5 mm activation of the transpalatal distraction in all models using the nonlinear solution method in FEA. Unilateral displacement(mm) and stress distribution(MPa) were measured in three directions (x, y, and z axes) of craniofacial and maxillofacial structures in the symmetrical finite element models. In all models, the unilateral transverse displacements of the anterior teeth were greater than those of the posterior teeth, and the greatest displacement was at the central incisor level. The greatest displacement values at the central incisor level, at the anterior nasal spine(ANS) and at the posterior nasal spine(PNS) levels was measured in Model-IV, III, II and I, respectively. Mean elemental stress(von Mises stress) in the medial pterygoid plate, screw and lateral pterygoid plate regions from highest to lowest was measured in Model-IV, III, II and I, respectively. The maxilla performed outward rotation and tipping movement in all models during the expansion period. Among the distractor positions, the second molar region was found to be the most advantageous one in terms of expansion pattern. Considering the patient's anatomy and clinical conditions, placing the palatal distractor as posteriorly as possible will result in more effective maxillary expansion.

Dental, Skeletal, and Soft Tissue Changes after Bone-Borne Surgically Assisted Rapid Maxillary Expansion: A Systematic Review and Meta-Analysis

(1) Background: For non-growing patients with marked transverse maxillary deficiency, bone-borne surgically assisted rapid maxillary expansion (SARME) has been proposed as an effective treatment option. Objective: To evaluate the dental, skeletal, and soft tissue changes following bone-borne SARME. (2) Methods: An unrestricted systematic electronic search of six databases, supplemented by manual searches, was performed up to April 2023. The eligibility criteria included prospective/retrospective clinical studies with outcomes pertaining to objective measurements of dental/skeletal/soft tissue effects of bone-borne SARME in healthy patients. (3) Results: Overall, 27 studies satisfied the inclusion criteria. The risk of bias of the non-randomized trials ranged between moderate (20) and serious (4). For the two RCTs, there were some concerns of bias. Trials with outcomes measured at the same landmarks within the scope of the prespecified timeframe were deemed eligible for quantitative synthesis. Eventually, five trials were included in the meta-analysis. SARME was associated with a statistically significant lengthening of the dental arch perimeter immediately after expansion, along with a marginally significant decrease in palatal depth during the post-SARME retention period. Post-treatment SNA values exhibited no statistically significant change. (4) Conclusion: Current evidence indicates that bone-borne SARME constitutes an effective treatment option for adult patients with maxillary transverse deficiency. Further long-term randomized clinical trials with robust methodology, large sample sizes, and 3D evaluation of the outcomes are needed.

Alveolar bone changes after tooth-borne surgically assisted rapid maxillary expansion: A three-dimensional study

INTRODUCTION

Surgically assisted rapid maxillary expansion (SARME) with a dental-anchorage appliance can induce dental and skeletal complications adjacent to the teeth supporting the device. The purpose of this study was to quantify the dentoskeletal changes observed after SARME using a tooth-borne device.

MATERIALS AND METHODS

Cone beam CT images from 39 patients were compared between the preoperative (T1) and the postoperative period (T2). The mean time to complete the second imaging was 13.8 ± 6.9 months after the SARME. Dental and bone parameters were assessed: the vestibular bone height (BH), the bone thickness (BT), the existence of fenestrations, and the root resorption at the level of first upper premolar (P1) and the first upper molar (M1). The maxillary expansion parameters were also collected.

RESULTS

Both vertical and horizontal vestibular bone loss were observed mainly in the first upper molar sectors: The BT decreased from 0.93 ± 0.50 mm to 0.53 ± 0.51 mm (p < 0.0001) and the BH decreased from 1.84 ± 1.05 mm to 0.93 ± 1.02 mm (p < 0.0001) for tooth #16. The bone loss also affected the first upper premolars but in a more limited manner. Significant fenestrations were observed at the apex of the mesio-vestibular root of teeth #16 and #26. We noted significant root resorption affecting the mesio-, disto-vestibular and palatal roots of tooth #16 (mean reductions of 0.32, 0.35, and 0.55 mm, respectively; p < 0.05), and the palatal root of tooth # 26 (loss of 0.58 mm; p = 0.004). The mean bone expansion was 3.76 mm and 1.41 mm at the premolar and molar levels, respectively (p < 0.0001), while a mean 6.24 mm and 4.23 mm inter-cuspid expansion was noted at the P1 and M1 levels (p < 0.0001).

CONCLUSION

Our results document the vestibular bone changes and low root resorption, mostly in the molar sectors, associated with SARME using dental-anchorage devices.

Asymmetric Maxillary Expansion Introduced by Surgically Assisted Rapid Palatal Expansion: A Systematic Review

PURPOSE

A commonly reported complication of surgically assisted rapid palatal expansion (SARPE) that has not been explored extensively is uneven expansion between left and right sides, which requires secondary surgery for correction. This systematic review aims to analyze the prevalence and potential causes of asymmetric expansion in the transverse dimension after SARPE to guide the clinical practice.

METHODS

Electronic databases and manual search were used to search for original articles published on SARPE on March 11, 2022. Original human studies that recorded the number and percentage of asymmetric expansion after two-piece SARPE were included. The 2020 Preferred Reporting Items for Systemic Reviews and Meta-Analyses guideline was implemented for the quality assessment and data analysis of the included articles. The study was registered at the International Prospective Register of Systematic Reviews under the number CRD42022300782.

RESULTS

After applying inclusion and exclusion criteria, 13 articles were included in the final review. The risk of bias was high in 8 studies and medium in the other 5 studies. Overall, the prevalence of asymmetric expansion in the transverse dimension (different amount of expansion between left and right sides) was 7.52%, with 12.90% of patients involved receiving a second surgery for correction. Expander design did not significantly affect the rate of asymmetry expansion. Pterygomaxillary fissure release significantly increased the rate of asymmetry expansion (11.02% vs 5.08%, P < .001). In comparison, lateral nasal wall osteotomy (4.26% vs 14.77%, P < .001) and release of the nasal septum (5.22% vs 17.15%, P < .001) significantly lowered the rate of asymmetry expansion, respectively.

CONCLUSIONS

Asymmetric dentoskeletal expansion between left and right sides is a common complication of SARPE procedures, mostly caused by variations in surgical cuts. However, the risk of bias in currently available publications is high. Further studies are warranted to fully understand the causes of asymmetric expansion.

Surgically assisted maxillary expansion with or without pterygoid disjunction alters maxillomandibular positioning

PURPOSE

This study aimed to analyze alterations in mandibular positioning after surgically assisted maxillary expansion (SARME) with and without pterygoid disjunction (PD).

METHODS

Cone-beam computed tomography scans of 24 healthy individuals (18-45 years old) with transverse deficiency, superior to 5 mm, underwent SARME with or without PD. The aspects prospectively assessed were (1) alignment and position of the head (ITK-Snap and 3D Slicer software); (2) McNamara's and Steiner-Tweed-Wits' cephalometric analysis (Dolphin Imaging®); and (3) colorimetric evaluation based on 3D correspondence analysis (3D Slicer software).

RESULTS

A decrease in 1-NA and 1-SN angles as well as an increased occlusal plane in both groups was observed. Superior-inferior and anteroposterior spatial displacements of the chin were statistically significant in the PD group. Altered colorimetric patterns were also observed in the PD group.

CONCLUSIONS

This study found more evident tooth inclination in the group without PD; mandibular alterations were more evident in the PD group. Further studies with 3D analysis are strongly recommended for more comprehensive results.

Effects of the different administration frequencies of teriparatide (PTH [1-34]) on new bone formation of expanded midpalatal sutures in rats: A histomorphometric and micro-computed tomography analysis

OBJECTIVE

The aim of the study was to evaluate the effect of 4 μg/kg teriparatide administered at intermittent and continuous frequencies on bone formation in the expanded midpalatal suture region using histomorphometric and micro-computed tomography (micro-Ct) analysis. Settings and sample population: In this study, 24 Sprague Dawley male rats were used.

METHODS

The experimental animals were divided into 3 groups as follows: Group 1: only maxillary expansion, Group 2: maxillary expansion with continuous teriparatide administration (2 μg in the morning and 2 μg in the evening) and Group 3: maxillary expansion with intermittent teriparatide administration (daily 4 μg/kg). The expansion appliance was fixed to maxillary incisors of all animals within the 5-day expansion period, followed by a 12-day retention phase. Animals were sacrificed at the end of the retention period, and specimens were evaluated by micro-Ct and histomorphometric analysis respectively.

RESULTS

The results of the histomorphometric analysis showed that Group 3 had the highest number of osteoblasts (1042 ± 90.76) (P < .01). In addition, the results of micro-Ct analysis revealed that Group 3 had the highest bone volume/total volume (16% ± 0), bone mineral density (173.82 ± 2.6 mgHA/cm³ ) and least midpalatal suture width (0.13 ± 0.001 mm) (P < .01). Osteoblasts number and micro-Ct analysis values of Group 2 were higher than those of Group 1 but no significant differences between them (P > .01).

CONCLUSION

Intermittently administered TP (4 μg/kg once a day) was seen to enhance bone formation and mineralization. In the future, it can be used in drug studies that will increase or stimulate bone formation as well as in the midpalatal suture area.

Three-segment versus 2-segment surgically assisted rapid maxillary expansion

OBJECTIVE

To compare the 2 surgically assisted rapid maxillary expansion (SARME) techniques, the conventional 2-segment osteotomy between maxillary central incisors and the 3-segment osteotomy between maxillary lateral incisors and canines bilaterally. Authors hypothesized that the 3-piece would provide better bone expansion.

STUDY DESIGN

A pilot study was conducted; 19 patients were divided into 2 groups: conventional 2-segment osteotomy (10 patients) and 3-segment osteotomy (9 patients). Dental and skeletal measurements of the preoperative and postoperative cone beam computed tomography images were analyzed. Pre- and postoperative periodontal probing was performed, patients' cosmetic perception was evaluated in a colored visual analog scale (VAS), and surgical time was measured with a regular chronometer.

RESULTS

Three-segment SARME resulted in greater bone expansion (5.12 vs 6.20 mm; P = .016), less molar inclination (7.16 vs 3.57 degrees; P = .028), better patient cosmetic perception (3.13 vs 7.68 in a VAS; P = .000), and longer surgical time (43 vs 52 minutes; P = .026). Furthermore, the 2-segment group presented necrosis of 1 central incisor.

CONCLUSIONS

Results suggest that 3-piece SARME is more effective for bone expansion of the maxilla.

Role of Navigation in Oral and Maxillofacial Surgery: A Surgeon's Perspectives

Surgeries related to the maxillofacial area deal with an intricate network of anatomical structures. With the complexity of the vital structures, it necessitates a surgical team to respect each anatomical boundary. In the past, there was an exceptionally high number of cases with surgical errors. These errors were not because of flaws in the surgeon’s skills or techniques but owing to lack of resources. Visualisation is one of the key factors that determines the precision of any surgical outcome. Advances in surgical planning have led to the introduction of a “Navigation” system that helps surgeons to see more, know more and ultimately do more for their patients. The usefulness of the navigation system in oral surgeries has been indicated by its surgical applications in craniomaxillofacial trauma, orthognathic surgeries, head and neck pathological resections, complex skull base surgeries and surgery involving temporomandibular joint. A vast majority of research literature has suggested remarkable improvement in surgical outcomes under the guidance of 3d planning and navigation. However, with such an inordinate advancement, financial expenses and a gradual learning curve are always a constraining factor in surgical navigation. This article overviews indication of navigation in craniofacial surgeries with a focus on applied aspect, planning and solution to the future problem.

Immediate dental and skeletal influence of distractor position on surgically assisted rapid palatal expansion with or without pterygomaxillary disjunction

The outcome of surgically assisted rapid palatal expansion (SARPE) can be affected by pterygomaxillary disjunction (PMD) and the distractor position. In this study, SARPE was performed, with or without PMD, in 20 fresh cadaver heads. Transverse expansion was conducted twice using a bone-borne distractor in the anterior and posterior positions, resulting in four groups (n=10). Cone beam computed tomography scans were completed before and after SARPE to evaluate maxillary changes. A comparative anterior decrease and posterior increase in midpalatal opening resulted from SARPE with PMD combined with a posteriorly placed distractor. Significant differences in the internal transverse changes were found between the two SARPE techniques combined with an anterior distractor at the level of the premolars and molars for alveolar ridge width (P=0.040, P=0.024), and at the level of the molars for the dental crown width (P=0.017) and corresponding tooth cusp width (P=0.018). In contrast, using a posteriorly placed distractor led to a significant difference for tooth cusp width only (P=0.050). No statistically significant differences were found between external transverse changes or between distractor positions. PMD is more important in achieving a more uniform and parallel transverse expansion pattern than the distractor position. However, a posterior distractor seems to intensify the effects of PMD.

Stability and surgical complications of tooth-borne and bone-borne appliances in surgical assisted rapid maxillary expansion: a systematic review

The objective of this systematic review was to evaluate the stability and complications of tooth-borne (TB), bone-borne (BB) and hybrid (TB-BB) appliances in surgically assisted rapid maxillary expansion (SARME). Database searches were conducted (PubMed, Embase, Cochrane Library and SciELO), as well as a grey literature search (Google Scholar) and hand searches of reference lists. Forty-six articles were included after study selection (κ=0.854). After eligibility assessment, 16 articles and one article from the grey literature were processed (κ=0.866) and six articles were selected by hand searching, for a total of 23 articles included. Regarding stability, TB appliances showed width relapse rates ranging from 4 to 35% in canines, from 1 to 37% in premolars and from 0.2 to 49.5% in molars. In BB appliances, width relapse rates were 1.7-21% in canines, 1.5% in premolars and 4.6-11.5% in molars. In hybrid appliances, the width relapse rate was 14% in premolars, with a 1.8% overexpansion reported in the molar region. In TB and BB appliances, skeletal relapse rates were similar on the nasal floor (11-53% and 41.6%, respectively) and at the level of the maxilla (18% and 16%, respectively). The most common complications were bone resorption in TB appliances (18.14%) and appliance-related complications in BB appliances (17.9%). The risk of bias was high in 19 studies, medium in three studies and low in one study. The TB and BB appliances used in SARME were considered to have a high long-term stability. BB appliances appeared to have fewer relapses than TB appliances due to a more parallel distribution of forces exerted. However, relapse appears to be highly influenced by postorthodontic treatments, where arch-form coordination is achieved in the consolidation period with the purpose of overexpansion correction, alignment and final vertical adjustments. Further randomised controlled trials with long-term data and large sample sizes are needed to support evidence-based clinical decision-making and to allow meta-analytic studies of stability outcomes regarding the type of anchorage in SARME.

Effect of the pterygomaxillary disjunction on surgically assisted rapid palatal expansion in context of orthodontic treatment

OBJECTIVE

This retrospective study analyzed the dentoalveolar effects of pterygomaxillary disjunction (PMD) in surgically assisted rapid palatal expansion (SARPE) after orthodontic treatment.

STUDY DESIGN

Virtual study casts before and after orthodontic treatment involving SARPE were analyzed in 12 patients without (-) PMD and 15 patients with (+) PMD. Linear and angular measurements and maximum deviations on the alveolar ridge and hard palate were determined.

RESULTS

Dental arch widths in the first molars of the (-) and (+) PMD groups increased to 6.07 ± 2.11 mm and 6.61 ± 2.33 mm (P = .96) and the corresponding axial angles increased to 0.34 ± 9.45 degrees and 2.39 ± 9.59 degrees (P = .58), respectively. The palatal angles changed by about 0.10 ± 11.50 degrees and 1.74 ± 14.56 degrees (P = .75) in the (-) and (+) PMD groups and the maximum labial deviations at the alveolar ridge were 3.04 ± 0.76 mm and 3.22 ± 1.16 mm (P = .65) for the (-) and (+) PMD groups, respectively. Statistically significant differences were found before and after surgery (P < .04), but no significant differences were observed in PMD after orthodontic treatment.

CONCLUSIONS

SARPE led to a significant transverse expansion, and the dental effects were more than the skeletal effects. We did not find a significant difference between both surgical techniques with regard to the anterior and posterior parts of the maxilla or the corresponding dentition.

A comparison of tooth-borne and bone-anchored expansion devices in SARME

PURPOSE

Major adult maxillary transverse discrepancies are usually treated with surgically assisted rapid maxillary expansion (SARME), utilizing a combination of surgical and orthodontic techniques. Unfortunately, a consensus has not been reached on topics ranging from the best surgical technique that should be performed to the ideal expander type that should be installed. The present study sought to evaluate the efficiency and stability of the maxillary expansion achieved with two types of expanders following the same SARME procedure without pterygomaxillary disjunction (PMD).

METHODS

Twenty-four patients with a maxillary transverse deficiency were enrolled in the study. All patients underwent the same SARME, and 12 received a bone-anchored (KLS Martin®) and 12 were installed with a tooth-borne (Hyrax®) expander. Dental impressions were collected both preoperatively and 1 year postoperatively. These casts were scanned and the distances between specific interdental and intergingival points were measured and analyzed. Statistical analyses were performed to assess the effects expander type had on the efficiency of the maxillary expansion and long-term stability.

RESULTS

Expansion in the anterior maxillary and premolar regions was found to be similar in both groups. In contrast, the tooth-borne device resulted in a significantly greater expansion in the molar region.

CONCLUSION

The SARME technique without PMD is highly effective at treating adults with maxillary transverse deficiencies, and the type of expander selected depends on the location of the larger maxillary constriction region of each patient.

Evaluation of photobiomodulation effects on pain, edema, paresthesia, and bone regeneration after surgically assisted rapid maxillary expansion: Study protocol for a randomized, controlled, and double blind clinical trial

BACKGROUND

Surgically assisted rapid maxillary expansion (SARME) generates an uncomfortable postoperative period accompanied by pain, edema, and paresthesia. There are few studies on the effect of photobiomodulation (PBM) after SARME and it was not possible to find studies on the efficacy of light emitted by diode (LED) after this type of intervention. The main objective of the study will be to evaluate the efficacy of PBM with LED in the control of pain, facial edema, paresthesia, and bone repair after SARME.

METHODS

A randomized, double-blind, placebo-controlled clinical trial involving 72 participants aged from 18 to 45 years, who search the Department of Buccomaxillofacial Surgery and Traumatology of Mandaqui Hospital Complex, will be conducted. Immediately after surgeries, the participant will be inserted into the placebo or LED group. In the LED group, the participants will receive PBM with an extraoral device (660 and 850 nm with 6 J per point) and an intraoral device (660 nm with 2 J per point) and in the control group the person in charge of the application will simulate the irradiation with the devices kept off. The applications will be in the immediate postoperative period, 1, 2, 7, 14, 30, 60, 90, and 120 days after the end of the surgeries, when the evaluations will also be performed. Facial measurements, extra and intraoral sensitivity, pain and bone repair will be evaluated. Secondarily, data regarding the occurrence of headache; otalgia; nausea; bruising; nasolacrimation; epistaxis; dysphagia; systemic and superficial temperature in the operated region; use of analgesics and anti-inflammatories; anxiety and impact of oral health on the participants' quality of life will be computed.

DISCUSSION

Since PBM has shown positive effects on postoperative complications of other types of oral surgery and also has a positive effect on bone repair after maxillary disjunction, surgically assisted or not, it seems clear the need to evaluate its performance regarding pain, edema, and paresthesia after these surgeries.

TRIAL REGISTRATION

This protocol was registered in Clinical Trials platform (https://clinicaltrials.gov/) with the number NCT03814525, first published and last updated on January 24, 2019.

Surgically assisted rapid maxillary expansion: a systematic review of complications

A systematic review of the literature on the complications of surgically assisted maxillary expansion (SARME) was performed. The search strategy was based on the PRISMA guidelines. The PubMed, SCOPUS, and Cochrane Library databases were searched. Data were extracted from the full texts after screening of the abstracts and titles. Human clinical studies encompassing 'maxillary expansion', 'palatal expansion', 'SARME', or 'SARPE' and that reported sufficient data for 'complication' were included. In vitro studies, case reports, meta-analyses, reviews, book chapters, animal studies, and studies with missing or insufficient data were excluded. The final selection included 12 articles for data extraction. A total of 851 patients underwent SARME, with 187 reported complications (21.97%). Epistaxis (2.47%) and postoperative pain (2.00%) were the most often reported minor complications, and asymmetric or inadequate expansion presented an occurrence rate of 4.47%. Minor complications were equally distributed between surgical (49.30%) and orthodontic complications (50.70%). The technique without pterygomaxillary disjunction increased the occurrence of minor complications (29.95% vs. 16.87%), and the expansion pattern with less than 0.5 mm/day increased the occurrence of orthodontic complications (30.93% vs. 1.83%), i.e. asymmetric expansion. In conclusion, SARME procedures mostly present minor complications. Although several types of complication are described in the literature, occurrence rates are low, and technical issues such as pterygomaxillary disjunction and the pattern of distraction can be predictors of the complication risk.

Massive Middle Cerebral Artery Infarction After Surgically Assisted Rapid Palatal Expansion: A Case Report

Dentofacial deformities have a marked impact on a patient's quality of life. Fortunately, these deformities often can be corrected through orthodontic and surgical treatment. In adults, transverse maxillary discrepancies are often corrected by performing a surgically assisted rapid palatal expansion (SARPE) procedure. This procedure is accompanied by many of the same complications involved in performing a Le Fort I osteotomy. Although major complications from maxillary surgery are uncommon, severe hemorrhage and cerebrovascular accidents are real risks accompanied by serious sequelae. The purpose of this case report is to describe a case in which a patient developed a massive middle cerebral artery infarct after a SARPE procedure. The authors discuss the possible etiology and pathogenesis of the complication. They also aim to remind surgeons of this rare complication to ensure prompt recognition and management to prevent delays in care.