Sagittal and Vertical Maxillary Effects After Surgically Assisted Rapid Maxillary Expansion (SARME) Using Haas and Hyrax Expanders

Dentoperiodontal and skeletal changes induced by miniscrew-assisted rapid maxillary expansion (C-expander) treatment in adults: A retrospective clinical trial

INTRODUCTION

The objective of this study was to evaluate the dental periodontal and skeletal response to ≥5 mm of expansion width achieved by C-expander treatment with posterior miniscrews placed between the first and second molars in adults.

METHODS

A total of 28 patients aged 21.91 ± 3.20 years with maxillary transverse deficiency underwent C-expander treatment. Anterior miniscrews were positioned between the first and second premolars, whereas posterior miniscrews were positioned between the first and second molars. Cone-beam computed tomography records were obtained before expansion and 3 months after expansion. The dental periodontal and skeletal changes for all patients were recorded.

RESULTS

The C-expander treatment expanded the palatal suture with slight buccal alveolar bone inclination. An increase in the nasal cavity width and a greater increase in the maxillary base bone width were observed after maxillary expansion. The expansion at the posterior nasal spine (3.78 mm) was approximately 85.7% of that at the anterior nasal spine (4.41 mm). No significant buccal dehiscence occurred after expansion, whereas the mesiobuccal alveolar bone thickness of the first molars was decreased at the 8 mm level with respect to the cementoenamel junction. The first molar showed decreased inclination (right, -0.45°; left, -0.38°, P >0.05), whereas the expansion at the apical level was less than that at the crown level. Age and the skeletal/dental expansion ratio had no discernible relationship.

CONCLUSIONS

Miniscrew-assisted C-expander treatment can be effective for adults with maxillary transverse deficiency. Rearward placement of the miniscrews may create an approximately parallel expansion. Most maxillary expansion was derived from skeletal expansion with slight alveolar bone buccal inclination.

Sagittal and Vertical Changes of the Maxilla after Surgically Assisted Rapid Palatal Expansion: A Systematic Review and Meta-Analysis

Surgically assisted rapid palatal expansion (SARPE) is often performed to correct the transverse deficiency in the maxilla for skeletally mature patients. However, there is little consensus on the sagittal and vertical displacement of the maxilla after SARPE. This systematic review aims to analyze the position changes of the maxilla in the sagittal and vertical dimensions after the completion of SARPE. Registered with PROSPERO (registration number: CRD42022312103), this study complied with the 2020 PRISMA guideline and was conducted on 21 January 2023. Original studies were screened from MEDLINE (PubMed), Elsevier (SCOPUS), and Cochrane, and supplemented by hand-searching. Cephalometric changes of skeletal vertical and sagittal measurements were the focus. A fixed-effects model was applied in R for meta-analysis. After applying inclusion and exclusion criteria, seven articles were included in the final review. Four studies had a high risk of bias, and the other three had a medium risk of bias. Meta-analysis revealed that the SNA angle increased by 0.50° ± 0.08° (95% confidence interval, 0.33° to 0.66°), and the SN-PP angle increased by 0.60° ± 0.09° (95% confidence interval, 0.41° to 0.79°) after SARPE. In summary, the maxilla displayed statistically significant forward and clockwise downward movement after SARPE. However, the amounts were small and might not be clinically significant. Due to the high risk of bias of included studies, our results must be taken cautiously. Future studies are needed to discern the effects of direction and angulation of the osteotomies of SARPE on the displacement of the maxilla.

The effect of subspinal Le Fort 1 corticotomy on nasal morphology in surgically assisted rapid palatal expansion

The purpose of this retrospective study was to evaluate the influence of subspinal Le Fort 1 corticotomy (SLF1C) on nasal morphology in patients treated with surgically assisted rapid palatal expansion (SARPE) using three-dimensional (3D) stereophotogrammetry images. A total of 64 patients were enrolled in the study and divided into two groups according to the surgical approach that was used: in group 1 (n = 32) SARPE was performed using a conventional Le Fort 1 corticotomy (CLF1C), and in group 2 (n = 32) SARPE was performed using a subspinal Le Fort 1 corticotomy (SLF1C). Measurements of alar and columellar width, and nasolabial angle were taken on 3D stereophotogrammetry images before and after SARPE using Vectra 3D camera system. Both surgical groups showed a statistically significant increase in alar and columellar width, and nasolabial angle postoperatively (p<0.05). SLF1C resulted in significantly smaller changes of the columellar base postoperatively (p=0.0456). The datasuggests that SARPE with an osteotomy of the anterior nasal spine as an additional step to the conventional Le Fort 1 corticotomy results in a smaller increase of the columellar base.

Cephalometric measures correlate with polysomnography parameters in individuals with midface deficiency

To determine the association between cephalometric measurements and polysomnographic parameters in Brazilian patients with midface deficiency. This was a primary, clinical, observational, longitudinal, retrospective, analytical, and single-center study. Forty-eight patients with midface deficiency were divided into two groups as follows: those who underwent surgically assisted rapid palatal expansion (SARME) and those who received maxillary advancement (MA). Pre- and post-operative cephalometric and polysomnography measurements were obtained. Pearson's correlation was used to verify the presence of any significant associations between PSG scores and cephalometric measurements. Associations between BMI (Body Mass Index) and AHI (Apnea Hypopnea Index) as well as arousals were observed. In the SARME group, associations between AHI and SNA, UAS and MP-H, arousals and SNA, and Co-A and MP-H were noted. Associations between AHI and Co-A, PoOr-A and MP-H, arousals and UAS, and between minimum saturation of O2 and SNA, SNB, and Co-A were observed in the MA group. This study demonstrates the alterations in the middle third of the face that were related to sleep disturbance. In addition, it shows the associations between the polysomnographic parameters and the cephalometric representations corresponding to the analyzed deformities and transverse or anteroposterior maxillary deficiencies.

Bone changes on lateral cephalograms and CBCT during treatment of maxillary narrowing using palatal osteodistraction with bone-anchored appliances

The most common problem in surgical and orthodontic treatment involves abnormal transverse dimension of the maxilla. Behaviour of the facial skeleton in its anterior-posterior dimension during treatment of maxillary narrowing using surgical assist is interesting to observe. Assessment of bone changes of the maxillary location assessed on lateral cephalograms and CBCT during surgically assisted maxillary expansion with bone-anchored appliances. The analysed material included documentation of 78 patients, the mean age of 16.86±2.65, treated with transverse maxillary distraction using a bone-anchored appliance. The software (Dolphin Imaging) was used to measure parameters on lateral cephalograms. Results obtained analysis of correlation between planes, angles and diameters between teeth before and after treatment. Simple Regression - SNA vs. SN-OCCL change of the anterior height with regard to changes in the occlusal angle refer to the opening and dropping of the maxilla in the anterior section. Simple Regression - SNA vs. S-PNS-ANS describe changes in the anterior section such as opening of the S-PNS-ANS angle, and in a correlation with the SNA angle opening it indicates maxillary dropping and protrusion. Dropping and protrusion of the maxilla can be observed during surgically assisted maxillary expansion with bone-anchored appliances. Maxillary anterior movement may depend on a surgical procedure.

Effects of surgically assisted rapid maxillary expansion on mandibular position: a three-dimensional study

Background

This study aimed to evaluate three-dimensional changes in mandibular position after surgically assisted rapid maxillary expansion (SARME).

Methods

A retrospective study was carried out with tomographic records of 30 adult patients with maxillary transverse deficiency who underwent SARME. Cone beam computed tomography scans were obtained preoperatively (T1), after expansion (T2) and 6 months after expansion (T3). Mandibular landmarks were measured with respect to axial, sagittal, and coronal planes. Repeated measures ANOVA was used for statistical analysis.

Results

Clockwise rotation and lateral displacement of the mandible were observed immediately after SARME. However, mandibular displacements tended to return close to their initial values at T3.

Conclusions

Clockwise rotation and lateral shift of the mandible are transient effects of SARME.

Evaluations of sagittal and vertical changes induced by surgically assisted rapid palatal expansion

INTRODUCTION

Class II, anterior open bite and/or a steep mandibular plane angle are frequently considered a contraindication to the use of surgically assisted rapid palatal expansion (SARPE). Nevertheless, few studies have investigated the maxillary and mandibular effects after SARPE on the sagittal and vertical planes, with dissimilar results and small samples of patients.The aim of the current study was to evaluate the sagittal and vertical effects after SARPE.

METHODS

Twenty-one consecutive adult patients (7 males, 14 females; mean age, 25.6 ± 6.3 years) who required SARPE were included in this study. All patients were subjected to subtotal LeFort I osteotomy with pterygomaxillary disjunction. Lateral cephalometric radiographs were taken during the preoperative assessment (T0) and 6 months after the end of the expansion (T1). Cephalometric measurements were realized at T0 and T1 for all the patients. Independent-sample t test and analysis of variance were used.

RESULTS

Statistically significant changes were observed only in upper incisor^NA (P = 0.04). No skeletal sagittal or vertical variation was found after SARPE.

CONCLUSIONS

Class II, anterior open bite and/or a steep mandibular plane angle cannot be considered an outright contraindication to its use. Upper incisor palatal inclination could result after SARPE.

Three-dimensional computed tomographic analysis of changes to the external features of the nose after surgically assisted rapid maxillary expansion and orthodontic treatment: a prospective longitudinal study

INTRODUCTION

The aim of this prospective, longitudinal study was to evaluate changes to the external shape and form of the nose after surgically assisted rapid maxillary expansion and orthodontic treatment. The changes were registered using a 3-dimensional computer tomography technique, based on superimposition on the anterior base of the skull.

METHODS

The subjects comprised 35 patients (mean age, 19.7 years; range, 16.1-43.9 years). Low-dose, helical computerized tomography images were taken at treatment start and after orthodontic treatment, about 18 months postsurgery. The 3-dimensional models were registered and superimposed on the anterior cranial base.

RESULTS

There were in general significant widening and overall anterior and inferior displacement of the nasal soft tissues. The changes varied in size and direction. No correlation was found between the initial and final widths of the nose, or between the initial and final widths of the nostrils.

CONCLUSIONS

After surgically assisted rapid maxillary expansion, the most obvious changes to the external features of the nose were at the most lateral alar bases. The difference in lateral displacement profoundly influenced the perception of a more rounded nose. Patients with narrow and constrained nostrils can benefit from these changes. The 3-dimensional superimposition applied in this study is a reliable method, circumventing projection and measurement errors.

Effect of low-level laser therapy (GaAlAs) on bone regeneration in midpalatal anterior suture after surgically assisted rapid maxillary expansion

OBJECTIVE

The aim of this study was to evaluate the effects of laser therapy on bone regeneration in the midpalatal anterior suture (MPAS) after surgically assisted rapid maxillary expansion (SARME).

METHODS

Thirteen patients aged between 18 and 33 years old with maxillary transverse deficiency (> or =7.0 mm) were evaluated. All patients underwent subtotal Le Fort I osteotomy with separation of the pterygomaxillary suture with the use of Hyrax expander, and were divided into 2 groups: control group (n = 6) and laser group (n = 7). A GaAlAs laser (P = 100 mW, lambda = 830 nm, Ø = 0.06 cm(2)) was used. The laser was applied in 8 treatment sessions with intervals of 48 hours. Each treatment session consisted of laser applications, per point (E = 8.4J, ED = 140J/cm(2)), at 3 points on the MPAS, and total dose of E = 25.2 J, ED = 420 J/cm(2). Digital radiographs were taken before the surgical procedure and at 1-, 2-, 3-, 4-, and 7-month follow-up visits. Optical density analysis of the regenerated bone was performed using Adobe Photoshop 8.0 software.

RESULTS

Bone regeneration associated with the use of laser after SARME showed a statistically significant difference. A higher mineralization rate was found in the laser group (26.3%, P < .001) than the control group.

CONCLUSION

Low-level laser irradiation (GaAlAs) accelerates bone regeneration in MPAS after SARME. However, the optical density measurements after 7 months of follow-up were lower in comparison with the preoperative measurements.

Transverse effects after surgically assisted rapid maxillary expansion in the midpalatal suture using computed tomography

Surgically assisted rapid maxillary expansion is the treatment of choice for correcting maxillary transverse deficiency in adults. Traditionally, the appliance for expansion is tooth-borne and tissue-tooth-borne devices (Hyrax and Haas). Although a number clinical and radiographic studies have evaluated the surgically assisted rapid maxillary expansion, only limited information is available to study the transverse movement of the midpalatal suture with computed tomography. Forty adult patients of both sexes, ranging in age from 18 to 38 years, with bilateral transverse maxillary deficiency were operated on. Twenty patients had Hyrax expander, and 20 had Haas expander. Under general anesthesia, subtotal Le Fort I osteotomy was performed including pterygomaxillary dysjunction. The width of the midpalatal suture opening was measured at the anterior edge of the midpalatal suture and at the junction of the midpalatal suture and palatal bones, using computed tomography in axial acquisition, obtained in the preoperative period and immediately after the end of expansion. A digital caliper was used to measure Haas and Hyrax distance on the central jackscrew preoperatively and postoperatively. The proportion between the midpalatal suture expansion and the amount of expansion on the jackscrew was evaluated. The mean of midpalatal suture opening and screw opening for Haas group was 5.19 and 8.78 mm, and for the Hyrax group, 5.85 and 8.51 mm, respectively. Both groups showed parallel-shaped separation of the midpalatal opening with no significant difference in the anterior and posterior portion. Midpalatal/jackscrews opening proportion was greater in the Hyrax group (69,2%) than in the Haas group (60%).