Comparison of the skeletodental effects of miniscrew-anchored and tooth-anchored facemask treatment in growing patients with skeletal class III malocclusions.

INTRODUCTION: This retrospective study aimed to evaluate the skeletal and dental effects of the miniscrew-anchored facemask in skeletal Class III growing patients and compare them with those of conventional tooth-anchored facemasks. METHODS: Retrospectively a total of 50 patients with skeletal Class III (mean ANB: -1.12°) were investigated and divided into two groups according to the treatment modality. Twenty-five patients were treated using the conventional tooth-anchored facemask (T group: mean age 9.3 ± 1.1 years, mean ANB: -0.93°) whereas the other 25 were treated using a miniscrew-anchored facemask (M group: mean age 9.7 ± 1.3 years. mean ANB: -1.61°). Two miniscrews were placed on the palate for bone anchorage. In both T and M groups, facemasks applied a force of 20-30° down on the occlusal plane, and the force increased from 200 g to 300-350 g per side throughout the treatments. The patients were instructed to wear facemasks for at least 14 h per day. A total of 16 angular and 11 linear cephalometric measurements were analysed to determine the skeletal and dental changes before and after facemask treatment. A paired t-test was used to verify the effects before and after treatment in each group. RESULTS: All miniscrews were well maintained during treatment. The values of SNA, SN-ANS, ANB and A to N-Perp, which indicate anterior protraction of the maxilla, were significantly higher in the M group compared with the T group (P < .05). Proclination of the maxillary incisors, extrusion and mesialization of the maxillary molars were significantly greater in the T group (P < .05). CONCLUSIONS: Miniscrew-anchored facemask treatment increased the amount of maxillary protraction and reduced the dental side effects compared with conventional tooth-anchored facemask treatment in growing patients with skeletal Class III malocclusion.

Specialised ribosomes as versatile regulators of gene expression.

The ribosome has long been thought to be a homogeneous cellular machine that constitutively and globally synthesises proteins from mRNA. However, recent studies have revealed that ribosomes are highly heterogeneous, dynamic macromolecular complexes with specialised roles in translational regulation in many organisms across the kingdoms. In this review, we summarise the current understanding of ribosome heterogeneity and the specialised functions of heterogeneous ribosomes. We also discuss specialised translation systems that utilise orthogonal ribosomes.

Effect of Observer's Sex and Chin Prominences on the Perception of the Lower Lip-Chin Prominence Angle.

ABSTRACT: This study aimed to identify the preferred range of lower lip-chin prominence angles in the Korean population and evaluate the effect of the individual lower lip-chin prominence angle on perceptions of esthetic chin profile.Chin prominence silhouettes were used to assess the lower lip-chin prominence preference. The observers randomly categorized each image as (1) normal, (2) slightly abnormal but not requiring surgical correction, and (3) abnormal and requiring surgery. Individual lower-chin prominence angles of all observers were analyzed using standardized clinical photographs.The normal range of lower lip-chin prominence angle is 0° to 25°; socially acceptable range is 0° to -10°, 25° to 40°; range needing surgery is -10° to -30° and 40° to 45°. Women are more tolerant to chin protrusion. A protrusive chin is more acceptable in observers with retrusive chin profile.Skeletal Class II profile is more acceptable than skeletal Class III in the Korean population. The individual lower-chin prominence angle could affect perception of desired surgery. These findings indicate that patient-specific treatment planning is important in achieving satisfaction in chin surgery.

Cone-Beam Computed Tomography Evaluation of Pharyngeal Airway Space Changes After Bimaxillary Orthognathic Surgery in Patients With Class III Skeletal Deformities: A 6-Year Follow-Up Study.

PURPOSE: The aim of the present study was to investigate the volumetric and 2-dimensional (2D) changes in the pharyngeal airway space (PAS) after bimaxillary orthognathic surgery (maxillary advancement and mandibular set back) in patients with skeletal Class III deformities. PATIENTS AND METHODS: In the present retrospective study, patients with skeletal Class III deformities were treated at Pusan National University Hospital (Busan, South Korea) and had undergone cone-beam computed tomography examination preoperatively, immediately postoperatively, 6.0 ± 0.6 months postoperatively, and 6.2 ± 1.3 years postoperatively. The anteroposterior length (APL), largest transverse width (LTW), and cross-sectional area (CSA) at 4 reference planes and the PAS volume were measured. Spearman's correlation analysis was used to assess the correlation between the PAS changes and skeletal movements. RESULTS: The subjects included 11 men and 12 women. Their mean age was 22.7 ± 4.7 years (range, 18 to 33 years). The APL and CSA on the PNS-Vp, CV1, and CV2 planes, the LTW on the CV1 plane, and the oropharyngeal and total volume had decreased at 6 months postoperatively. However, thereafter, no significant 2D or volumetric changes were observed until 6.2 years postoperatively. The long-term change of the LTW on the CV3 plane correlated negatively with mandibular relapse. CONCLUSIONS: The volume and morphology of the 6-month postoperative changes in PAS were stable at 6 years for patients who had undergone maxillary advancement and mandibular setback.

Functional conservation of specialized ribosomes bearing genome-encoded variant rRNAs in Vibrio species.

Heterogeneity of ribosomal RNA (rRNA) sequences has recently emerged as a mechanism that can lead to subpopulations of specialized ribosomes. Our previous study showed that ribosomes containing highly divergent rRNAs expressed from the rrnI operon (I-ribosomes) can preferentially translate a subset of mRNAs such as hspA and tpiA in the Vibrio vulnificus CMCP6 strain. Here, we explored the functional conservation of I-ribosomes across Vibrio species. Exogenous expression of the rrnI operon in another V. vulnificus strain, MO6-24/O, and in another Vibrio species, V. fischeri (strain MJ11), decreased heat shock susceptibility by upregulating HspA expression. In addition, we provide direct evidence for the preferential synthesis of HspA by I-ribosomes in the V. vulnificus MO6-24/O strain. Furthermore, exogenous expression of rrnI in V. vulnificus MO6-24/O cells led to higher mortality of infected mice when compared to the wild-type (WT) strain and a strain expressing exogenous rrnG, a redundant rRNA gene in the V. vulnificus CMCP6 strain. Our findings suggest that specialized ribosomes bearing heterogeneous rRNAs play a conserved role in translational regulation among Vibrio species. This study shows the functional importance of rRNA heterogeneity in gene expression control by preferential translation of specific mRNAs, providing another layer of specialized ribosome system.

The Effect of Biomimetic Remineralization of Calcium Phosphate Ion Clusters-Treated Enamel Surfaces on Bracket Shear Bond Strength.

Purpose: To evaluate the remineralization effect of calcium phosphate ion clusters (CPICs) on demineralized enamel surfaces and their effects on bracket shear bond strength. Patients and Methods: Extracted premolars were prepared in resin blocks. The samples in the form of resin blocks were divided into five experimental groups: control group, demineralized group, and groups of CPIC solution treatment for 30, 60, and 90s. The specimens were examined using scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDX), microhardness testing, micro-computed tomography (micro-CT) assessment, shear bond strength (SBS) test, and adhesive remnant index (ARI) score. Results: The SEM images revealed epitaxial growth of enamel and a decrease in the thickness of the demineralized enamel layer when treated with CPIC solution. The EDX analysis revealed an increase in the Ca/P ratio in the CPIC-treated groups. The microhardness value significantly increased when treated with CPICs; however, it showed a lower value than that of the sound enamel groups. As a result of the micro-CT test, radiolucency decreased gradually as the CPIC treatment time increased. The SBS test and ARI score results showed an improvement in bonding stability after treatment with CPICs. Conclusion: We demonstrated an enamel biomodification approach using CPIC solution treatment, which is a promising strategy for enamel remineralization. Specifically, remineralization of demineralized enamel improves the orthodontic bracket SBS.

Effects of different distalization directions and methods on maxillary total distalization with clear aligners: a finite element study.

OBJECTIVES: To analyze the effects of maxillary tooth distalization by clear aligner (CA) treatment with variations in the angular direction of the distalization force, presence of attachments, and force-application method used. MATERIALS AND METHODS: A finite element model containing alveolar bone, dentition, and periodontal ligament was constructed. Analytical model groups were as follows: (1) distalization with buttons (without attachments), (2) buttons on canines (with attachments), (3) precision cuts on the canines (without attachments), and (4) precision cuts on the canines (with attachments). A distalization force of 1.5 N was applied to the button or precision cut at -30°, -20°, -10°, 0°, 10°, 20°, and 30° to the occlusal plane. RESULTS: As the direction of force approached +30°, the dentition inclined posteriorly. The posterior movement pattern was significantly influenced by the presence of an attachment and the direction of force, rather than the area where the force was applied. Distal inclination was dramatically reduced with attachments. A disengagement or deformation of the CA may reduce the distalization efficiency of the dentition or move the dentition in an inappropriate direction. CONCLUSIONS: Attachments for efficient distalization by the CA are necessary. The use of miniscrews in the direction of force parallel to the occlusal plane is more advantageous than the use of Class II elastics. Due to CA deformation, distalization with the button on the canines can be more effective for distal movement of the maxillary dentition.

Biomechanical analysis for different mandibular total distalization methods with clear aligners: A finite element study.

Objective: : The purpose of this finite element method (FEM) study was to analyze the biomechanical differences and tooth displacement patterns according to the traction direction, methods, and sites for total distalization of the mandibular dentition using clear aligner treatment (CAT). Methods: : A finite element analysis was performed on four FEM models using different traction methods (via a precision cut hook or button) and traction sites (mandibular canine or first premolar). A distalization force of 1.5 N was applied to the traction site by changing the direction from -30 to +30° to the occlusal plane. The initial tooth displacement and von Mises stress on the clear aligners were analyzed. Results: : All CAT-based total distalization groups showed an overall trend of clockwise or counterclockwise rotation of the occlusal plane as the force direction varied. Mesiodistal tipping of individual teeth was more prominent than that of bodily movements. The initial displacement pattern of the mandibular teeth was more predominant based on the traction site than on the traction method. The elastic deformation of clear aligners is attributed to unintentional lingual tipping or extrusion of the mandibular anterior teeth. Conclusions: : The initial tooth displacement can vary according to different distalization strategies for CAT-based total distalization. Discreet application and biomechanical understanding of traction sites and directions are necessary for appropriate mandibular total distalization.

Is it worth applying self-irrigation after third molar extraction? A randomised controlled trial.

In this study, we aimed to examine the effectiveness of self-irrigation following the extraction of mandibular third molars. A randomised controlled clinical trial was conducted with 155 patients who had undergone extraction of a mandibular third molar. The irrigation group was instructed to self-irrigate the extraction socket with tap water using a syringe three times a day, starting seven days after the tooth extraction. The incidence of complications and mouth opening, halitosis, plaque/gingival index, and oral health-related quality of life (OHRQoL) were measured. The irrigation group showed a lower incidence of complications than the non-irrigation group. The halitosis, plaque, and gingival scores were lower by mean (SD) 19.66 (5.19), 0.58 (0.06), and 0.62 (0.08), respectively, in the irrigation group than in the non-irrigation group (p = 0.0001). A greater amount of food packing was associated with higher halitosis, plaque, and gingival scores and poorer OHRQoL (p < 0.05). Further, more frequent irrigation was associated with lower halitosis, plaque, and gingival scores and better OHRQoL (p ≤ 0.016). Self-irrigation of the extraction socket using a syringe containing tap water is a very effective method for keeping the extraction socket clean. This technique reduced halitosis, improved plaque and gingival indices, and increased OHRQoL.

A remineralizing orthodontic etchant that utilizes calcium phosphate ion clusters.

This study aimed to investigate whether a phosphoric acid (H3PO4) solution containing calcium phosphate ion clusters (CPICs) could minimize enamel damage during long-term bracket bonding by dissolving the enamel surface and promoting enamel remineralization. The experimental design is as follows: first, three experimental etchants (H3PO4, CPICs-incorporated H3PO4 solution-I, and CPICs-incorporated H3PO4 solution-II) and two bonding resins (conventional orthodontic resin and self-adhesive orthodontic resin) were used in combination to create six groups, respectively. Each of these six groups was then divided into two sub-groups based on the presence or absence of thermocycling (TC). Twenty samples were assigned to each of the 12 groups (independent variables), and thus a total of 240 metal bracket-attached human premolars were used in this experiment. Bracket debonding was performed on each of 20 premolars in 12 groups, and shear bond strength (SBS) and adhesive remnant index (ARI) values were measured as dependent variables. Next, the three experimental etchants were applied (independent variables) to each of the three enamel samples, and the remineralization of the enamel surface was investigated as a dependent variable. The enamel surface was observed using electron scanning and atomic force microscopy. Furthermore, X-ray diffraction, energy dispersive spectroscopy (EDX) spectrum X-ray spectroscopy, and elemental mapping were performed, and the Knoop microhardness scale was measured. Therefore, the experiment was performed in two steps: SBS and ARI measurements for 12 groups, followed by observation of the enamel surface and microhardness measurements, according to the three types of etchants. As a result of the experiment, first, when the bracket was debonded, SBS did not decrease, and residual adhesive was hardly observed in the C2A group (before TC), C2A, and C1C groups (after TC) (p < 0.001). Second, the experimental etchant containing CPICs achieved remineralization while demineralizing the enamel. This was verified through SEM/EDX, element mapping, XRD, and AFM. Also, the roughness and microhardness of the enamel surface were better in the remineralized surface by the experimental etchant containing CPICs (p < 0.017). The CPICs-incorporated H3PO4 solution reduced ARI while maintaining SBS during bracket debonding, regardless of whether TC was performed or the type of resin. The etchant containing CPICs was also shown to remineralize the enamel and increase its microhardness.

Enhanced antimicrobial and remineralizing properties of self-adhesive orthodontic resin containing mesoporous bioactive glass and zwitterionic material.

Abstract Background/purpose: Self-adhesive resins (SARs) do not require additional restorative adhesives and provide adequate adhesion to mineralized dental structures by shortening the bonding time in clinics where moisture control and isolation are difficult. The aim of this study was to evaluate the mechanical and biological properties of SARs containing mesoporous bioactive glass nanoparticles (MBNs) and 2-methacryloyloxyethyl phosphorylcholine (MPC) and to determine their antibacterial and remineralization effects. Materials and methods: MBNs and MPC were added to SARs to improve their physical properties and remineralization ability. The experimental resins assessed in this study were SARs mixed with 3%MPC, 5%MPC, 1%MBN+3%MPC, or 3%MBN+3%MPC. The shear bond strength, microhardness, adhesive remnant index, ion dissolution, degree of conversion, and antibacterial properties of the SARs were evaluated. To assess the remineralization properties, micro-computed tomography analysis was performed after pH cycling. Results: Increasing the MBN content in SAR resulted in higher microhardness compared to the control SAR. The shear bond strength decreased in the SAR+5%MPC group and increased in the SAR+1%MBN+3%MPC and SAR+3%MBN+5%MPC groups. Conclusion: Our findings suggest that SARs containing MBNs and MPC have antibacterial and remineralization effects on the enamel.

Gold nanoparticle-DNA aptamer-assisted delivery of antimicrobial peptide effectively inhibits Acinetobacter baumannii infection in mice.

Acinetobacter baumannii causes multidrug resistance, leading to fatal infections in humans. In this study, we showed that Lys AB2 P3-His-a hexahistidine-tagged form of an antimicrobial peptide (AMP) loaded onto DNA aptamer-functionalized gold nanoparticles (AuNP-Apt)-can effectively inhibit A. baumannii infection in mice. When A. baumannii-infected mice were intraperitoneally injected with AuNP-Apt loaded with Lys AB2 P3-His, a marked reduction in A. baumannii colonization was observed in the mouse organs, leading to prominently increased survival time and rate of the mice compared to those of the control mice treated with AuNP-Apt or Lys AB2 P3-His only. This study shows that AMPs loaded onto AuNP-Apt could be an effective therapeutic tool against infections caused by multidrug-resistant pathogenic bacteria in humans.

Long-term condylar remodelling after bimaxillary orthognathic surgery in skeletal Class III patients.

In this study, we aimed to evaluate long-term condylar remodelling in skeletal Class III patients who underwent bimaxillary orthognathic surgery using cone-beam computed tomography (CBCT). Twenty-three patients were studied retrospectively, and a total of 4 CBCT scans were obtained for each subject: 1 month before surgery (T0), immediately after the surgery (T1), 6 months after the surgery (T2), and 6.1 (±2.1 years after the surgery) (T3). Condylar remodelling was measured using the condylar volume, height, width, and depth. To examine a significant change, a one-way repeated measures analysis of variance was performed. The correlation between postoperative skeletal movement and condylar volume was assessed using Spearman's correlation analysis. Condylar volume and height showed a significant decrease from T1 to T2 but a significant increase from T2 to T3. Furthermore, a significant decrease was observed between T1 and T3. The condylar width and depth showed no significant changes. Postoperative skeletal movement showed no correlation with the change in condylar volume. The change in condylar volume mostly occurred as the condylar height changed. However, it did not contribute much to the postoperative skeletal movement.

Transcript-specific selective translation by specialized ribosomes bearing genome-encoded heterogeneous rRNAs in V. vulnificus CMCP6.

Ribosomes composed of genome-encoded heterogeneous rRNAs are implicated in the rapid adaptation of bacterial cells to environmental changes. A previous study showed that ribosomes bearing the most heterogeneous rRNAs expressed from the rrnI operon (I-ribosomes) are implicated in the preferential translation of a subset of mRNAs, including hspA and tpiA, in Vibrio vulnificus CMCP6. In this study, we show that HspA nascent peptides were predominantly bound to I-ribosomes. Specifically, I-ribosomes were enriched more than two-fold in ribosomes that were pulled down by immunoprecipitation of HspA peptides compared with the proportion of I-ribosomes in crude ribosomes and ribosomes pulled down by immunoprecipitation of RNA polymerase subunit ß peptides in the wild-type (WT) and rrnI-completed strains. Other methods that utilized the incorporation of an affinity tag in 23S rRNA or chimeric rRNA tethering 16S and 23S rRNAs, which generated specialized functional ribosomes in Escherichia coli, did not result in functional I-ribosomes in V. vulnificus CMCP6. This study provides direct evidence of the preferential translation of hspA mRNA by I-ribosomes.

Current trends in orthognathic surgery.

Orthognathic surgery has steadily evolved, gradually expanding its scope of application beyond its original purpose of simply correcting malocclusion and the facial profile. For instance, it is now used to treat obstructive sleep apnea and to achieve purely cosmetic outcomes. Recent developments in three-dimensional digital technology are being utilized throughout the entire process of orthognathic surgery, from establishing a surgical plan to printing the surgical splint. These processes have made it possible to perform more sophisticated surgery. The goal of this review article is to introduce current trends in the field of orthognathic surgery and controversies that are under active discussion. The role of a plastic surgeon is not limited to performing orthognathic surgery itself, but also encompasses deep involvement throughout the entire process, including the set-up of surgical occlusion and overall surgical planning. The authors summarize various aspects in the field of orthognathic surgery with the hope of providing helpful information both for plastic surgeons and orthodontists who are interested in orthognathic surgery.

Effects of Poly(Amidoamine) Dendrimer-Coated Mesoporous Bioactive Glass Nanoparticles on Dentin Remineralization.

Dentin hypersensitivity (DH) is one of the most common clinical conditions usually associated with exposed dentinal surfaces. In this study, we identified the effectiveness of poly(amidoamine) (PAMAM) dendrimer-coated mesoporous bioactive glass nanoparticles (MBN) (PAMAM@MBN) on DH treatment, examining the ion-releasing effect, dentin remineralization, and the occluding effect of dentinal tubules. We synthesized MBN and PAMAM@MBN. After soaking each sample in simulated body fluid (SBF), we observed ion-releasing effects and dentin remineralization effects for 30 days. Also, we prepared 30 premolars to find the ratio of occluded dentinal tubules after applying MBN and PAMAM@MBN, respectively. The results showed that PAMAM did not disrupt the calcium ion-releasing ability or the dentin remineralization of MBN. The PAMAM@MBN showed a better occluding effect for dentinal tubules than that of MBN (p < 0.05). In terms of dentinal tubule occlusion, the gap between MBN was well occluded due to PAMAM. This implies that PAMAM@MBN could be effectively used in dentinal tubule sealing and remineralization.

The estimation of skeletal maturity of patients with cleft lip and palate using statistical shape analysis: a preliminary study.

OBJECTIVES: To propose a skeletal maturity assessment method by developing a statistical regression analysis model through the integration of lateral and axial images of the cervical vertebrae of patients with cleft lip and palate obtained through CBCT. METHODS: 49 patients with cleft lip and palate (28 females, 21 males; age range, 4-16 years) underwent CBCT examination, and the hand-wrist radiographic data were selected. With coordinates of landmarks from lateral and axial images of the cervical vertebrae, Procrustes analysis and principal component (PC) analysis yielded PC scores of each cervical vertebra, with the centroid size as the size factor. The meaningful PC scores from these were used for multiple regression models. RESULTS: When both axial and lateral cervical vertebrae were used together, there was a 6.7% increase in the Sempé maturation level explanatory power for skeletal maturation estimation in females and an 11.4% increase in males compared with that when only the chronological age was used. CONCLUSIONS: This study improved the estimating regression models using statistical shape analysis with lateral and axial cervical vertebral shapes. The obtained models had improved explanatory power for skeletal maturity estimation than previous studies with healthy people.

Qualitative correlation between postoperatively increased vertical dimension and mandibular position in skeletal class III using partial-least-square path modeling.

BACKGROUND: This study constructed a partial-least-square path-modeling (PLS-PM) model and found the pathway by which the postsurgical vertical dimension (VD) affects the extent of the final mandibular setback on the B point at the posttreatment stage for the skeletal class III surgery-first approach (SFA). METHODS: This study re-analyzed the data from the retrospective study by Lee et al. on 40 patients with skeletal class III bimaxillary SFA. Variables were obtained from cone beam computed tomography (CBCT)-generated cephalograms. Authors investigated all variables at each time point to build a PLS-PM model to verify the effect of the VD on the final setback of the mandible. RESULTS: From PLS-PM, an increase in VD10 was found to decrease the absolute value of the final setback amount of the mandible, which reflects the postsurgical physiological responses to both surgery and orthodontic treatment, which, in turn, can be interpreted as an increase in postoperative mandibular changes. CONCLUSIONS: To resolve the issue of collinear cephalometric data, the present study adopted PLS-PM to assess the orthodontic treatment. From PLS-PM, it was able to summarize the effect of increased postsurgery occlusal vertical dimension on the increased changeability of the B point position at the posttreatment stage.

Cervical Vertebral Body's Volume as a New Parameter for Predicting the Skeletal Maturation Stages.

This study aimed to determine the correlation between the volumetric parameters derived from the images of the second, third, and fourth cervical vertebrae by using cone beam computed tomography with skeletal maturation stages and to propose a new formula for predicting skeletal maturation by using regression analysis. We obtained the estimation of skeletal maturation levels from hand-wrist radiographs and volume parameters derived from the second, third, and fourth cervical vertebrae bodies from 102 Japanese patients (54 women and 48 men, 5-18 years of age). We performed Pearson's correlation coefficient analysis and simple regression analysis. All volume parameters derived from the second, third, and fourth cervical vertebrae exhibited statistically significant correlations (P < 0.05). The simple regression model with the greatest R-square indicated the fourth-cervical-vertebra volume as an independent variable with a variance inflation factor less than ten. The explanation power was 81.76%. Volumetric parameters of cervical vertebrae using cone beam computed tomography are useful in regression models. The derived regression model has the potential for clinical application as it enables a simple and quantitative analysis to evaluate skeletal maturation level.

Optimal application of compressive palatal stents following mesiodens removal in pediatric patients: A Randomized Controlled Trial / Aplicación óptima de stents palatinos de compresión después de la extracción del mesiodens en pacientes pediátricos: un ensayo controlado aleatorio

Background: There is no scientific evidence supporting the choice of a palatal stent in patients who underwentremoval of an impacted supernumerary tooth. We aimed to investigate the effects of palatal stents in patients whounderwent supernumerary tooth removal through a palatal approach and to suggest the optimal stent thicknessand material.Material and Methods: We recruited 144 patients who underwent extraction of a supernumerary tooth between themaxillary anterior teeth. Subjects were assigned to a control group (CG) or one of four compressive palatal stentgroups (CPSGs) classified by the thickness and material of the thermoplastic acrylic stent used. Palatal gingivalswelling and objective indices (healing, oral hygiene, gingival, and plaque) were evaluated before surgery and onpostoperative days (PODs) 3, 7, and 14; pain/discomfort and the Child Oral Health Impact Profile (COHIP) wereassessed as subjective indices of the effects of the stent.Results: The CPSGs showed faster healing than did the CG on PODs 7 (P<0.001) and 14 (P=0.043); swelling wasmeasured by 1.64±0.88 mm and 4.52±0.39 mm, respectively. Although swelling was least in the 4-mm hard group(0.92±0.33 mm), the difference compared with that in the 2-mm hard group (1.01±0.18 mm) was not significant(P=0.077). The CPSGs showed better COHIP (P<0.001-0.036) and pain scores (P<0.001) than did the CG onPODs 1-3. Conclusions: Compressive palatal stents reduce discomfort by decreasing pain and alleviating swelling. Althougha stent is effective regardless of its thickness and material, 2-mm hard stents maximized such positive effects withminimal discomfort.(AU)