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Objective To quantitatively analyze the effect of nicotine on orthodontic tooth movement (OTM) and bone remodeling in rats using micro-computed tomography and tartrate-resistant acid phosphatase immunostaining. Methods Thirty-nine adult male Sprague-Dawley rats were randomized into three groups: group A, 0.5 mL normal saline (n = 9, 3 per 3, 7, and 14 days); group B, 0.83 mg/kg nicotine (n = 15, 5 per 3, 7, and 14 days); and group C, 1.67 mg/kg nicotine (n = 15, 5 per 3, 7, and 14 days). Each animal received daily intraperitoneal injections of nicotine/saline from the day of insertion of identical 30-g orthodontic force delivery systems. A 5-mm nickel-titanium closed-coil spring was applied between the left maxillary first molar (M1) and the two splinted incisors. The rate of OTM and volumetric bone changes were measured using micro-computed tomography. Osteoclasts were counted on the mesial alveolar bone surface of the distobuccal root of M1. Six dependent outcome variables, including the intermolar distance, bone volume fraction, bone mineral density, trabecular thickness, trabecular volume, and osteoclast number, were summarized using simple descriptive statistics. Nonparametric Kruskal-Wallis tests were used to evaluate differences among groups at 3, 7, and 14 days of OTM. Results All six dependent outcome variables showed no statistically significant among group-differences at 3, 7, and 14 days. Conclusions The findings of this study suggest that nicotine does not affect OTM and bone remodeling, although fluctuations during the different stages of OTM in the nicotine groups should be elucidated in further prospective studies.

The computer-aided design/computer-aided manufacturing (CAD/CAM) virtual orthodontic system produces customized brackets, indirect bonding jigs, and archwires based on a three-dimensional virtual setup. In surgical cases, this system helps to visualize the final occlusion during diagnosis and to efficiently plan individualized presurgical orthodontic treatments. A 20-year-old female patient with a skeletal Class III malocclusion, maxillary protrusion, and lip protrusion was successfully treated with orthognathic surgery and orthodontic treatment with maxillary first premolar extractions. The CAD/CAM system was applied for efficient treatment, with a total active treatment time of 16 months. In this case report, the applicability of the CAD/CAM virtual orthodontic system for orthognathic surgery cases is demonstrated. Suggestions are also made to overcome the limitations and to maximize the advantages of this system during orthodontic treatment of patients undergoing orthognathic surgery.

Objective Increased gingival elasticity has been implicated as the cause of relapse following orthodontic rotational tooth movement and approaches to reduce relapse are limited. This study aimed to investigate the effects of sulforaphane (SFN), an inhibitor of osteoclastogenesis, on gene expression in gingival fibroblasts and relapse after rotational tooth movement in beagle dogs. Methods The lower lateral incisors of five beagle dogs were rotated. SFN or dimethylsulfoxide (DMSO) were injected into the supra-alveolar gingiva of the experimental and control group, respectively, and the effect of SFN on relapse tendency was evaluated. Changes in mRNA expression of extracellular matrix components associated with gingival elasticity in beagles were investigated by real-time polymerase chain reaction. Morphology and arrangement of collagen fibers were observed on Masson’s trichrome staining of buccal gingival tissues of experimental and control teeth. Results SFN reduced the amount and percentage of relapse of orthodontic rotation. It also decreased the gene expression of lysyl oxidase and increased the gene expression of matrix metalloproteinase (MMP) 1 and MMP 12, compared with DMSO control subjects. Histologically, collagen fiber bundles were arranged irregularly and were not well connected in the SFN-treated group, whereas the fibers extended in parallel and perpendicular directions toward the gingiva and alveolar bone in a more regular and well-ordered arrangement in the DMSO-treated group. Conclusions Our findings demonstrated that SFN treatment may be a promising pharmacologic approach to prevent orthodontic rotational relapse caused by increased gingival elasticity of rotated teeth in beagle dogs.

Background The traditional method of distraction required a long period until the new bone was fully fused. This study aimed to evaluate the effect of cyclic and repetitive compressive force on new bone formation by applying a newly designed microactuator-generated distractor compared with the traditional distraction protocol. Methods The distraction devices were applied to the right and left mandibles of eight mature beagles, four of which were allocated to the experimental group and the other four to the control group. After a 5-day latency period, in the experimental group, 1.5-mm distraction and 0.5-mm compression were alternately applied every 12 hours; and in the control group, 0.5-mm distraction was repeated every 12 hours to perform a total of 7-mm mandibular lengthening. After an 8-week consolidation period, microstructure analysis using micro-computed tomography and histologic evaluations were performed. Results Bone volume fraction and trabecular number were significantly higher in the experimental group. Trabecular thickness did not show a significant difference, and trabecular separation was significantly higher in the control group. The measurement of new bone was significantly higher in the experimental group, but the difference in mineral apposition rate between the experimental and control groups was not statistically significant. Conclusions This study has revealed that applying cyclic compressive and tensile forces during the distraction period induces better new bone formation than repetitive distraction alone. In addition, the new distraction device produced reliable distraction results during the experiment.

Introduction The registration of cone-beam computed tomography (CBCT) images and digital dental models is required for the design and manufacturing of dental devices such as implant guides and surgical wafers. This study aims to register intraoral scan (IS) models and cast scan (CS) models onto CBCT images using 3-dimensional (3D) planning software and evaluate the registration accuracy according to scanning methods and 3D planning software. Methods The CBCT image of an artificial skull model with reference markers was taken. The CS model and the IS model were obtained from the same skull model, registered onto the CBCT image using 3D planning software packages providing manual registration (MR) function and point-based registration (PR) functions, and set as the experimental groups. After registration, shell to shell deviations and positional differences between the reference model and the experimental models were evaluated. Results The shell to shell deviations ranged from 0.03 to 0.18 mm. Deviations in both the maxilla and mandible were significantly different according to scanning methods and software packages. In the anteroposterior direction, the IS-MR and CS-MR groups showed significantly different positions. In the superoinferior direction, the MR and PR groups showed significantly different positions. Conclusions The registration using the PR function of the 3D planning software packages was significantly more accurate than the registration using the MR function. There was no significant difference between the registrations using the IS model and the CS model when using the PR functions.

Compliance with a mandibular advancement device is important for the optimal treatment of obstructive sleep apnea. Recent advances in information and communication technology-based monitoring and intervention for chronic diseases have enabled continuous monitoring and personalized management. Self-evaluation and self-regulation through objective monitoring and feedback may improve compliance. The aim of this study was to evaluate the effects of information and communication technology-based remote monitoring and feedback services, using a smartphone application, on the objective compliance with a mandibular advancement device in patients with obstructive sleep apnea. Forty individuals who were diagnosed with obstructive sleep apnea by polysomnography were randomly assigned to groups A and B. During an initial 6-week evaluation period, the mandibular advancement device-wearing time was monitored with the smartphone application in group B, but not in group A. The two groups then switched the monitoring procedures during the second 6-week period (the smartphone application was then used by group B, but not by group A). If no input data were indicated on the cloud server of the smartphone application during the monitored period, push notifications were provided twice daily. Objective compliance, monitored by a micro-recorder within the mandibular advancement device, was noted and compared based on whether the monitoring service was provided. The number of mandibular advancement device-wearing days was significantly higher in the monitored period than in the unmonitored period. The mandibular advancement device-wearing time did not differ significantly between the two groups. In conclusion, information and communication technology-based remote monitoring and feedback services demonstrated a potential to increase the objective measures of compliance with mandibular advancement devices.

To elucidate genetic factors affecting orthodontic treatment duration, we employed targeted next-generation sequencing on DNA from the saliva of 117 patients undergoing orthodontic treatment after premolar extraction. The clinical characteristics of patients were summarized, and the association of clinical variables with treatment duration was assessed. Patients whose treatment duration deviated from the average were classified into an extreme long group or an extreme short group. We identified single nucleotide polymorphisms (SNPs) significantly enriched in the two groups via targeted sequencing. Nine SNPs (six genes) were significantly enriched in both groups. In the extreme long group, the frequency of the CC genotypes of WNT3A, SPP1 (rs4754, rs9138), and TNFSF11, the TT genotype of SPP1 (rs1126616), as well as the GG genotype of SFRP2 was significantly higher than in the short group. In the extreme short group, the TC genotype of SPP1, the AA genotype of P2RX7, the CT genotype of TNFSF11, and the AG genotype of TNFRSF11A tended to exhibit higher frequency than in the long group. Taken together, we identified genetic polymorphisms related to treatment duration in Korean orthodontic patients undergoing premolar extraction. Accurate prediction of the treatment period through further research will be of great aid to patients as well as orthodontists.

Objectives To date, the clinical stability of dual-thread orthodontic miniscrews has not been studied. This study aimed to compare the primary stability and long-term clinical success rate of dual-thread and cylindrical orthodontic miniscrews and to examine the association between various clinical factors and the success rate of miniscrews. Materials and Methods A total of 145 cylindrical and 135 dual-thread miniscrews were inserted in the maxillary and mandibular buccal alveolar areas of 142 patients. The torque and Periotest (Siemens, Bensheim, Germany) values were recorded during insertion and removal. The effect of clinical variables such as sex, age, screw design, jaw, side of placement, root proximity, and site of placement on the success rate was examined using logistic regression analysis. Results There was no statistically significant difference (P = .595) in the overall clinical success rate between the two designs, with an overall success rate of 82.1% and 84.4% for the cylindrical and dual-thread miniscrews, respectively. Age and screw-root proximity were significantly associated with failure (P < .05). Conclusions The dual-thread miniscrews did not show superior long-term stability and clinical success rate as compared with the cylindrical miniscrews. The results of this study suggest that patient age and screw-root proximity influence the clinical success rate of miniscrews.

The plane formed by the intersection of bilateral porions (PoR and PoL) and left orbitale (OrL) is conventionally defined as the Frankfort horizontal (FH) plane. We aim to test the influence of the FH plane definition on a 3D cephalometric assessment. We selected 38 adult patients (20 males, 18 females, average age: 22.87 &plusmn, 5.17 years) without any gross asymmetry from retrospective records and traced and analyzed their cone-beam computed tomographic images. The findings were categorized into the following four groups: FH1: conventional, FH2: PoR, PoL, right orbitale (OrR), FH3: OrR, OrL, PoL, FH4: OrR, OrL, PoR. The average menton (Me) deviation from the MSP was statistically significant for the FH1 group (0.56 &plusmn, 0.27 mm, p &lt, 0.001), compared to the FH3 (1.37 &plusmn, 1.23 mm) and FH4 (1.33 &plusmn, 1.16 mm) groups. The spatial orientation level (SOL) of the FH plane showed a marked difference (p &lt, 0.05) between the FH2 (0.602&deg, &plusmn, 0.503&deg, ) and FH4 (0.944&deg, 0.778&deg, ) groups. The SOL of the MSP was comparatively small (p &lt, 0.001) for FH2 (0.015&deg, 0.023&deg, ) in comparison to both FH 3 (0.644&deg, 0.546&deg, ) and FH 4 (0.627&deg, 0.516&deg, ). Therefore, the FH plane definition can significantly influence the interpretation of cephalometric findings. Future studies should focus on standardization to improve the reliability and reproducibility of 3D cephalometry.

Objective Maxillary anterior segmental distraction osteogenesis (MASDO) for cleft and palate patients is the alternative treatment option to correct malocclusion with maxillary arch deficiency and severe crowding. After MASDO, prosthetic considerations are crucial for patients with cleft lip and palate because it is related to facial esthetics and occlusal function. The objectives of this study were to investigate the final restoration type for created alveolar space by MASDO. Methods Thirteen patients with cleft lip and palate who underwent MASDO and orthodontic treatment from the years 2000 to 2010 in Yonsei University were examined. Final restorations are classified as dental implants, conventional prosthesis, and orthodontic space closure. The relationship between the distracted areas and final restoration type was investigated. The authors evaluated lateral cephalograms obtained at predistraction osteogenesis (pre-DO; T1), postdistraction osteogenesis (post-DO; T2), and debond (T3), and measured changes from T1 to T2 and from T2 to T3. Results There was no significant difference of final restoration percentage of dental implants, conventional prosthesis, and space closure with orthodontic treatment. However, dental implants and conventional prostheses were applied more frequently in the posterior area and in the anterior area, respectively. The relapse rate was observed as 36.7% and 22.4% in the values of N-A distance and ANB angulation in T2-T3 stage. Conclusion The MASDO site should be decided, based on final restoration goal. Among the created alveolar spaces, implants were applied mainly to the posterior site and the conventional prostheses were mostly restored to the anterior site. For space closure by orthodontic approach, the area could be both anterior or posterior.

This study was performed to investigate the changes in gene expression in periodontal ligament (PDL) cells following mechanical stimulus through RNA sequencing. In this study, premolars extracted for orthodontic treatment were used. To stimulate the PDL cells, an orthodontic force of 100&times, g was applied to the premolar (experimental group, n = 11), whereas the tooth on the other side was left untreated (control group, n = 11). After the PDL cells were isolated from the extracted teeth, gene set enrichment analysis (GSEA), differentially expressed gene (DEG) analysis, and real-time PCR were performed to compare the two groups. GSEA demonstrated that gene sets related to the cell cycle pathway were upregulated in PDL. Thirteen upregulated and twenty downregulated genes were found through DEG analysis. Real-time PCR results confirmed that five upregulated genes (CC2D1B, CPNE3, OPHN1, TANGO2, and UAP-1) and six downregulated genes (MYOM2, PPM1F, PCDP1, ATP2A1, GPR171, and RP1-34H18.1-1) were consistent with RNA sequencing results. We suggest that, from among these eleven genes, two upregulated genes, CPNE3 and OPHN1, and one downregulated gene, PPM1F, play an important role in PDL regeneration in humans when orthodontic force is applied.

The aim of this study was to investigate the level of satisfaction for orthodontic treatment among adult patients. In addition, the influencing host factors were monitored for their associations with satisfaction.A questionnaire was designed to measure the level of satisfaction in 10 items; overall satisfaction, tooth alignment, facial appearance, eating and chewing, confident smile and self-image, retention state, treatment duration, treatment costs, intention to recommend, and relief of previous concerns, using a 5-point Likert scale. Total satisfaction was calculated by averaging the Likert scores from the 10 items. The survey was conducted, and the results from 298 adults were evaluated.For the overall satisfaction item, 45.0% were very satisfied, and 39.9% were satisfied, resulting in a satisfaction ratio of 84.9%. Total satisfaction score was 3.9. The level of satisfaction for tooth alignment and confident smile and self-image were significantly higher than facial appearance and eating and chewing (P 0.001). Patients aged 50 and above were more satisfied than the younger ones, and men were more satisfied than women (P 0.05).Overall, adult patients were highly satisfied with orthodontic treatment. Age, sex, motivation, expected concern, and discomfort influenced the level of satisfaction.

In this study, we assessed the precision and trueness of dental models printed with 3-dimensional (3D) printers via different printing techniques.Digital reference models were printed 5 times using stereolithography apparatus (SLA), digital light processing (DLP), fused filament fabrication (FFF), and the PolyJet technique. The 3D printed models were scanned and evaluated for tooth, arch, and occlusion measurements. Precision and trueness were analyzed with root mean squares (RMS) for the differences in each measurement. Differences in measurement variables among the 3D printing techniques were analyzed by 1-way analysis of variance (α = 0.05).Except in trueness of occlusion measurements, there were significant differences in all measurements among the 4 techniques (P 0.001). For overall tooth measurements, the DLP (76 ± 14 μm) and PolyJet (68 ± 9 μm) techniques exhibited significantly different mean RMS values of precision than the SLA (88 ± 14 μm) and FFF (99 ± 14 μm) techniques (P 0.05). For overall arch measurements, the SLA (176 ± 73 μm) had significantly different RMS values than the DLP (74 ± 34 μm), FFF (89 ± 34 μm), and PolyJet (69 ± 18 μm) techniques (P 0.05). For overall occlusion measurements, the FFF (170 ± 55 μm) exhibited significantly different RMS values than the SLA (94 ± 33 μm), DLP (120 ± 28 μm), and PolyJet (96 ± 33 μm) techniques (P 0.05). There were significant differences in mean RMS values of trueness of overall tooth measurements among all 4 techniques: SLA (107 ± 11 μm), DLP (143 ± 8 μm), FFF (188 ± 14 μm), and PolyJet (78 ± 9 μm) (P 0.05). For overall arch measurements, the SLA (141 ± 35 μm) and PolyJet (86 ± 17 μm) techniques exhibited significantly different mean RMS values of trueness than DLP (469 ± 49 μm) and FFF (409 ± 36 μm) (P 0.05).The 3D printing techniques showed significant differences in precision of all measurements and in trueness of tooth and arch measurements. The PolyJet and DLP techniques were more precise than the FFF and SLA techniques, with the PolyJet technique having the highest accuracy.

Objective: To investigate the effect of flapless osteoperforation on the tissue response of the atrophic alveolar ridge affected by orthodontic tooth movement (OTM). Materials and Methods: An atrophic alveolar ridge model was established in the mandibular quadrants of eight beagle dogs. As a split-mouth design, the quadrants were randomly divided into group C (OTM only) and group OP (OTM with flapless osteoperforation). The rate of OTM for 10 weeks was compared between groups, and micro-CT-based histomorphometric analysis and RNA-sequencing-based gene-enrichment analysis were performed targeting the atrophic ridge. Results: Group OP displayed more rapid tooth movement with lower bone mineral density and higher trabecular fraction in the atrophic ridge than did group C, showing no intergroup difference of total ridge volume. As contributing biological functional pathways in group OP, the genes related to osteoclast differentiation and TNF signaling pathway were up-regulated and those associated with Wnt signaling pathway and AMPK signaling pathway were down-regulated. Conclusions: Flapless osteoperforation facilitated the rate of OTM toward the atrophic ridge, maintaining low bone density, whereas it did not increase the volume of the atrophic ridge.

Purpose Few studies have evaluated the relapse pattern of intraoral vertical ramus osteotomy (IVRO) for the correction of mandibular prognathism with a high angle. The aim of this study was to measure the association between vertical facial types (high and normal mandibular plane angle) and relapse after IVRO for the management of mandibular prognathism. Materials and Methods The retrospective cohort study sample (skeletal Class III patients) was divided into 2 groups according to the angle of the sella-nasion plane relative to the mandibular plane (SN-MP) at the initial examination. Lateral cephalograms were analyzed for the predictor (facial type) and outcome (cephalometric changes over time) variables before surgery, 7 days after surgery, and 12 months after surgery. The 2 groups were matched for sample size (n = 20 in each). Data were analyzed using repeated-measures analysis of variance with Bonferroni correction. Results The normal-angle group (group N, SN-MP from 27° to 37°) and high-angle group (group H, SN-MP >37°) were not significantly different in terms of gender and age at the initial examination. Seven days after surgery, the mandibles in group H moved 2.5 mm more superiorly than those in group N (P = .013); consequently, the amount of overbite correction in group H was approximately 2 mm greater than that in group N (P = .002). Nevertheless, 12 months after surgery, there was no statistically significant difference in relapse of the maxilla and mandible between the 2 groups. In the 2 groups, the mandible moved approximately 0.7 mm superiorly during retention. Conclusions These findings suggest that IVRO is a clinically acceptable and stable treatment modality for mandibular prognathism with a high angle.

The aim of this study was to evaluate differences in the maxillary sinus floor levels between adults with an anterior open bite and those without.This retrospective study included 30 subjects: 15 adults with an anterior open bite (mean age, 21.5 ± 4.3 years) and 15 control subjects with normal occlusion (mean age, 21.7 ± 3.1 years). Cone-beam computed tomography and lateral cephalograms were analyzed before treatment.The open-bite group exhibited a significantly greater maxillary posterior alveolar height (P 0.05). The craniocaudal heights of the maxillary sinus in the region between the first and second molars and between the second premolar and first molar were significantly greater in the open bite group (40.5 and 39.0 mm, respectively) than in the control group (36.7 and 34.7 mm, respectively; P 0.05 for both). The basal bone heights in the regions between the first and second molars, the second premolar and first molar, and the first and second premolars were significantly smaller in the open-bite group than in the control group (P 0.001 for all).Vertical pneumatization of the maxillary sinus floor in the region between the first and second molars and between the second premolar and first molar is greater in adults with an anterior open bite than in those without, whereas basal bone height in the maxillary posterior region is lower in the open-bite patients.

The aim of this research was to verify that ultraviolet light (UV)-photofunctionalization improves the success rate and biomechanical stability of miniscrews regardless of length, and to evaluate the comparability of biomechanical stability between UV-photofunctionalized miniscrews with short lengths and untreated miniscrews with conventional lengths.Eight male beagles (age, 12-15 months; weight, 10-13 kg) received a total of 64 miniscrews, including 7-mm and 4-mm untreated and UV-photofunctionalized, acid-etched miniscrews with the use of a random block design. The cumulative success rates were examined in all studied groups. The insertion and removal torques and screw mobility were measured. Microcomputed tomographic scans and histomorphometric analyses were performed at 8 weeks postoperatively.The success rates of 7-mm UV-untreated and UV-photofunctionalized miniscrews were 87.5% and 100%, respectively, vs 43.8% for the 4-mm UV-untreated and 4-mm UV-photofunctionalized miniscrews. The rates were significantly different in accordance with the length (P 0.001). There were no differences in the insertion and removal torque and screw mobility between groups according to the length or UV treatment. However, the 4-mm UV-untreated miniscrews yielded a mean bone area ratio of 6.35 ± 7.43%, whereas the 7-mm UV-photofunctionalized miniscrew yielded a mean ratio of 32.17 ± 8.34% (P = 0.037).The UV-photofunctionalization significantly increased the biomechanical stability and led to increased bone and miniscrew contact area in dogs with miniscrews of the same length. However, the most important factor that affected the success rate of the miniscrew was the length.

When considering camouflage orthodontic treatment for Class III malocclusion with skeletal facial asymmetry, it is crucial to preserve the favorable compensated posterior occlusion. Once the inclination of the compensated occlusion is changed during orthodontic treatment, unstable occlusion, such as crossbite or scissor bite may occur. A 23-year-old female patient had anterior spacing with Class III malocclusion and a mandibular asymmetry. A nonsurgical approach was adopted. The treatment objectives were to establish a Class I molar relationship with compensated inclination of the posterior dentition and to correct the midline deviation. To achieve these goals, the computer-aided design/computer-aided manufacturing (CAD/CAM) orthodontic system plus customized brackets was applied, and miniscrews were used to distalize the left mandibular dentition for midline correction. The results suggested that the CAD/CAM-based customized brackets can be efficiently used in camouflage treatment to achieve a correct final occlusion.

Introduction We evaluated soft-tissue thickness changes after bimaxillary surgery according to vertical facial patterns in patients with skeletal Class III malocclusion with mandibular prognathism. Methods Forty-three Korean patients (16 men and 27 women; mean age, 22.6 ± 4.1 years) with skeletal Class III malocclusion who underwent bimaxillary surgery were divided into 2 groups: normal-angle group (N group) and high-angle group (H group), on the basis of the presurgical angle of the mandibular plane relative to the sella-nasion plane (SN-MP). Changes in hard-tissue landmarks and soft-tissue thickness before and after surgery were analyzed from reconstructed 3-dimensional cone-beam computed tomography images. Postoperative soft-tissue thickness in both groups was compared with that in 40 patients with normal skeletal Class I malocclusion in the reference group. Results Group N (27°-37°) and group H (>37°) did not differ significantly in terms of sex and age before surgery. Preoperative pogonion (Pog) thickness was significantly less in group H (9.7 ± 1.6 mm) than in group N (10.8 ± 1.9 mm) (P = 0.042). Adjusted multiple linear regression analysis showed a weak positive linear relationship between the SN-MP before surgery and soft-tissue Pog thickness change (R2 of 0.361; P = 0.001) after surgery, but the area below the lower lips was not completely normalized despite surgery. Conclusions The thickness of the soft-tissue Pog may increase slightly after surgery in patients with skeletal Class III malocclusion with a higher preoperative mandibular plane angle, but normalization in the area cannot be completely achieved despite surgery.

Decompression followed by enucleation, which is one of the treatments used for odontogenic keratocysts (OKCs), is frequently used in OKC lesions of large sizes. This method offers the advantage of minimizing the possibility of sensory impairment without creating a wide-range bone defect, moreover, the recurrence rate can be significantly lower than following simple enucleation. This study aimed to assess the changes in histology and expression of proliferation markers in OKCs before and after decompression treatment. A total of 38 OKC tissue samples from 19 patients who had undergone decompression therapy were examined morphologically and immunohistochemically to observe changes in proliferative activity before and after decompression. The markers used for immunohistochemistry (IHC) staining were Bcl-2, epidermal growth factor receptor (EGFR), Ki-67, P53, PCNA, and SMO. The immunohistochemistry positivity of the 6 markers was scored by using software ImageJ, version 1.49, by quantifying the intensity and internal density of IHC-stained epithelium. The values of Bcl-2, Ki-67, P53, proliferating cell nuclear antigen (PCNA), and SMO in OKCs before and after decompression showed no significant change. No correlation between clinical shrinkage and morphologic changes or expression of proliferation and growth markers could be found. There was no statistical evidence that decompression treatment reduces potentially aggressive behavior of OKC within the epithelial cyst lining itself. This might indicate that decompression does not change the biological behavior of the epithelial cyst lining or the recurrence rate.

The few studies on craniofacial complex changes in adults have reported contradictory findings. The aim of this study was to radiographically evaluate changes in the craniofacial complex and alveolar bone height of young adults over a 4-year period. This prospective study included 82 young adults (62 men; mean age, 19.0 ± 0.8 years; 20 women; mean age, 18.8 ± 0.9 years). Three radiographic examinations were performed longitudinally: the first (T0) was conducted at the start of the study, the second (T1) was conducted 2 years later, and the third (T2) was conducted at the end of the study period. As part of these examinations, lateral cephalograms, maxillary and mandibular anterior periapical radiographs, and bilateral posterior bitewing radiographs were obtained. During the 4-year follow-up period, all linear cephalometric measurements were significantly greater in men than in women. The amount of increase in the anterior facial height between T1 and T2 was lower in women than in men (P = 0.029). The rate of uprighting of the upper incisors was lower in men than in women over time (P = 0.020). The apex of the nose moved inferiorly between T0 and T2 (P = 0.006). The average overall change in the alveolar bone height was 0.27 mm and the yearly change was 0.07 mm over the 4-year period (P< 0.001). Significant changes in the skeletal, dental, and soft tissue, as well as, natural changes in alveolar bone, occur in young adults over time. Clin. Anat. 29:1011-1017, 2016. © 2016 Wiley Periodicals, Inc.

Objective: To evaluate the stability of nonsurgical miniscrew-assisted rapid maxillary expansion (MARME) in young adults with a transverse maxillary deficiency. Materials and Methods: From a total of 69 adult patients who underwent MARME followed by orthodontic treatment with a straight-wire appliance, 20 patients (mean age, 20.9 ± 2.9 years) with follow-up records (mean, 30.2 ± 13.2 months) after debonding were selected. Posteroanterior cephalometric records and dental casts were obtained at the initial examination (T0), immediately after MARME removal (T1), immediately after debonding (T2), and at posttreatment follow-up (T3). Results: Suture separation was observed in 86.96% of subjects (60/69). An increase in the maxillary width (J-J; 1.92 mm) accounted for 43.34% of the total expansion with regard to the intermolar width (IMW) increase (4.43 mm; P < .001) at T2. The amounts of J-J and IMW posttreatment changes were −0.07 mm (P > .05) and −0.42 mm (P = .01), respectively, during retention. The postexpansion change in middle alveolus width increased with age (P < .05). The postexpansion change of interpremolar width (IPMW) was positively correlated with the amount of IPMW expansion (P < .05) but not with IMW. The changes of the clinical crown heights in the maxillary canines, first premolars, and first molars were not significant at each time point. Conclusions: Nonsurgical MARME can be a clinically acceptable and stable treatment modality for young adults with a transverse maxillary deficiency.

In this study, we aimed to assess the surface characteristics and the biomechanical stability of miniscrews with an anodic oxidized surface compared with machined surface miniscrews in beagle dogs.Self-drilled, titanium-aluminum-vanadium alloy miniscrews with an anodic oxidized surface (n = 48) or a machined surface (n = 48) were placed into the mandibles of 12 beagle dogs. The surface characteristics of both types of miniscrews were analyzed before implantation with scanning electron microscopy and atomic force microscopy. Insertion torque was measured during placement of all 96 miniscrews. Half of the implants in each group (24 specimens per subgroup) received 200 to 250 g of tensile force for 3-week or 12-week loading periods. Removal torque was measured in 12 specimens of each subgroup, and bone-implant contact and bone volume were quantified in the other 12 specimens of each subgroup.Atomic force microscopy measurements demonstrated that the anodic oxidized surface miniscrews had significantly higher roughness parameters than did the machined surface miniscrews (P 0.001). The 2 types of miniscrews were not significantly different in insertion and removal torque values or in bone-implant contacts and bone volumes, regardless of the loading period.Anodic oxidized miniscrews have different surface roughness profiles but no clinically significant superiority in biomechanical stability compared with machined surface miniscrews.

The authors hypothesized that an audiovisual slide presentation that provided treatment information regarding the removal of an impacted mandibular third molar could improve patient knowledge of postoperative complications and decrease anxiety in young adults before and after surgery. A group that received an audiovisual description was compared with a group that received the conventional written description of the procedure.This randomized clinical trial included young adult patients who required surgical removal of an impacted mandibular third molar and fulfilled the predetermined criteria. The predictor variable was the presentation of an audiovisual slideshow. The audiovisual informed group provided informed consent after viewing an audiovisual slideshow. The control group provided informed consent after reading a written description of the procedure. The outcome variables were the State-Trait Anxiety Inventory, the Dental Anxiety Scale, a self-reported anxiety questionnaire, completed immediately before and 1 week after surgery, and a postoperative questionnaire about the level of understanding of potential postoperative complications. The data were analyzed with χ(2) tests, independent t tests, Mann-Whitney U tests, and Spearman rank correlation coefficients.Fifty-one patients fulfilled the inclusion criteria. The audiovisual informed group was comprised of 20 men and 5 women; the written informed group was comprised of 21 men and 5 women. The audiovisual informed group remembered significantly more information than the control group about a potential allergic reaction to local anesthesia or medication and potential trismus (P.05). The audiovisual informed group had lower self-reported anxiety scores than the control group 1 week after surgery (P .05).These results suggested that informing patients of the treatment with an audiovisual slide presentation could improve patient knowledge about postoperative complications and aid in alleviating anxiety after the surgical removal of an impacted mandibular third molar.

The aim of this work was to analyse the stability of vertical height reduction genioplasty using biodegradable material, as well as to determine vertical changes of hard and soft tissues during this procedure. Forty patients underwent vertical height reduction genioplasty using two types of biodegradable fixation (Biosorb FX® or OSTEOTRANS-MX®), combined with mandibular setback surgery. We assessed lateral cephalographs over time (pre-operation; immediately post-operation; 3 months, 6 months and 12 months post-operation). We found a mean vertical difference of 0.22mm (standard deviation (SD)=0.49mm) at the menton point immediately post-operation, compared with 12 months post-operation. And there was no statistical significance(P>0.05). The chin hard tissue remained stable from the immediate post-operation period to 1 year post-operation, and the chin soft tissue remained stable from 3 months to 1 year post-operation. The regression equation describing the replacement of hard tissue with soft tissue change, between pre-operation and 12 months post-operation is y=0.590x+0.885 (R2=0.300, P

Introduction The aim of this work was to compare the skeletal and dental outcomes of 1- versus 2-phase treatment in Class II subjects with difficult-to-treat high-angle severe Class II malocclusions. Methods The sample of 120 cases was collected from the private offices of 3 experienced clinicians. The following selection criteria were used: (1) ANB ≥6°, (2) SN-GoGn ≥37° or mandibular plane to Frankfort horizontal plane ≥30°; and (3) overjet ≥6 mm. Patients were classified into either the early or the late treatment group according to dental age (early Tx: ≥5 primary teeth; late Tx: otherwise). Thirty-four angular, linear, and proportional measurements were determined for each patient. Statistical significance was assessed with the use of a 2-tailed t test, analysis of covariance test, and chi-square test. Results The results showed that early 2-phase treatment for severe Class II high-angle patients offered no skeletal anteroposterior advantages over late 1-phase treatment. Severe high-angle Class II patients also showed similar dental anteroposterior outcomes with the use of both approaches. Vertically there was a higher frequency of increased mandibular plane angles and extrusion of upper incisors and lower molars in the late treatment group. Conclusions Early 2-phase treatment for severe Class II high-angle patients offered no skeletal or dental advantage over late 1-phase treatment.

Objective. The aim of this study was to evaluate the morphological characteristics of the palatal rugae in Korean subjects to determine whether the palatal rugae can be used as an appropriate reference area for three-dimensional digital model superimpositions. Materials and Methods. In total, 343 patients (110 men, 233 women; mean age, 25.6±8.2 years) who had a digital model taken at their initial visit were included, and the numbers and types of right and left palatal rugae were investigated according to the primary, secondary, and fragmentary rugae. Finally, the differences in the positions of the third primary ruga were investigated according to the presence of additional rugae posterior to the third primary ruga. Results. The number of primary palatal rugae ranged from one to six, with 43.5% of the subjects having three primary rugae and 36.1% having four primary rugae; there were no significant differences between sexes. Except for the fragment rugae, the numbers of primary and secondary rugae were not significantly different between the left and right sides. The third primary ruga was located more significantly anteriorly when there was an additional ruga posterior to the third primary ruga (P < 0.001). Conclusions. The numbers of the palatal rugae vary greatly among individuals, and this affects the anteroposterior position of the third primary ruga. When the third primary ruga is located anteriorly, care should be taken when using it as a reference area for superimposition with a digital model before and after orthodontic treatment.

To obtain the balance and harmony of the soft tissue facial profile in orthodontic treatment, it is necessary to identify the characteristics of overlying soft tissues according to the horizontal and vertical skeletal patterns. The aim of this study was to evaluate the perioral soft tissue characteristics of skeletal Class II Division 1 subjects (group II) with various vertical patterns compared with skeletal Class I subjects (group I).Lateral cephalograms of 99 Korean adults (44 women, 45 men; mean age, 23.4 years) were divided into 4 groups based on horizontal and vertical skeletal pattern (SN-MP angle): group I, 22 subjects; group II-low angle (27°), 14 subjects; group II-normal angle (27°-36°), 33 subjects; and group II-high angle (37°), 30 subjects. The correlations and multiple linear regression tests were used to determine the skeletal and dental variables influencing soft tissue characteristics.Group II-high angle showed significantly greater values than did group II-low angle for basic lower lip thickness and lower lip length. The perioral soft tissue measurements of group II were correlated with the inclination and anteroposterior position of the maxillary and mandibular incisors along with facial depth (N-Go) and facial length (S-Gn). Upper lip strain of group II was not influenced by any skeletal variables but only by the inclination and anteroposterior position of the maxillary incisors.Clinicians need to evaluate lip strain and lip thickness based on the skeletal pattern as well as dental inclination to obtain balance in the perioral muscle activity.

This study evaluates the effect of recombinant human bone morphogenetic protein-2 (rhBMP-2) on the quality and quantity of regenerated bone when injected into distracted alveolar bone.Sixteen adult beagle dogs were assigned to either the control or rhBMP-2 group. After distraction was completed, an rhBMP-2 dose of 330 μg in 0.33 mL was injected slowly into the distracted alveolar crest of the mesial, middle, and distal parts of the alveolar bone in the experimental group. Histologic and microcomputed tomography analyses of regenerated bone were done after 2 and 6 weeks of consolidation.After 6 weeks of consolidation, the vertical defect height in the middle of the regenerated bone was significantly lower in the rhBMP-2 group (2.2 mm) than in the control group (3.4 mm) (P0.05). Additionally, the width of the regenerated bone was significantly greater in the rhBMP-2 group (4.3 mm) than in the control group (2.8 mm) (P0.05). The bone density and volume of regenerated bone in the rhBMP-2 group were greater than in the control group after 6 weeks of consolidation (P0.001).Injection of rhBMP-2 into regenerated bone after a distraction osteogenesis procedure significantly increased bone volume in the dentoalveolar distraction site and improved both the width and height of the alveolar ridge and increased the bone density.

Objective Premaxillary distraction osteogenesis was introduced using intraoral devices to correct maxillary hypoplasia and lengthen the alveolar bone horizontally in a patient with unilateral cleft lip and palate. Methods For premaxillary distraction osteogenesis, Le Fort I osteotomy was performed. Vertical osteotomy lines were located distally of the upper right canine and left first premolar to separate the anterior segment of the maxilla. After a 7-day latency period, distraction was allowed to continue for 20 days at a rate of 0.5 mm/d, followed by a 3-month consolidation period. After consolidation, orthodontic treatment and bilateral intraoral vertical ramus osteotomy were performed for the mandibular setback. The implant and prosthodontic treatments were applied to the alveolar ridge area created by the distraction osteogenesis. Results The A-point moved 8.0 mm forward during the distraction osteogenesis period, and the recurrence rate was 25% after the retention period. The transverse dimension of the upper arch was expanded during orthodontic treatment. The quality of the alveolar bone created by distraction osteogenesis was acceptable for the prosthodontic implant. Conclusions Premaxillary distraction osteogenesis and arch expansion is an effective treatment strategy, improving function, aesthetics, and stability for cleft patients with multiple missing teeth.

Purpose: Due to the presence of various muscles around lips, variety of facial expression can be made and changes from aging process such as wrinkles can develop on the facial skin by the action of multiple muscles. In animals, skin and muscles are developed in the entire body. On contrast, they are well developed only in the face and just one is present in the neck and the palm. Alar band was defined as outer wrinkle formed by zygomaticus minor muscle, which is common in Koreans. This study aimed to investigate clinical prevalence of alar band. Materials & Methods: Subjects were chosen from 780 new patients who visited private clinic in Gyeonggi province for orthodontic treatment. Presence of alar band was examined from the smile extraoral photos. Correlation among skeletal form, lip protrusion, gender, and age were evaluated. Results: Prevalence of alar band was higher in women (27.9%) than in men (18.5%) with statistical significance (p

The aim of this study was to assess the association between malocclusion and oral health-related quality of life in young adults without orthodontic treatment, controlling for sociodemographic factors and common oral diseases.The sample consisted of 429 Korean patients (328 men, 101 women) 18 to 32 years of age. They completed the Korean version of the oral health impact profile-14 questionnaire and had a clinical examination, including an assessment with the index of orthodontic treatment need-dental health component. We collected sociodemographic information (age, sex, and education level) and evaluated other common oral diseases (decayed, missing, and filled teeth; periodontal health status; temporomandibular disorder; and oral soft tissue diseases).Multiple logistic regression analysis showed that patients requiring extensive orthodontic treatment were more than 2.7 times as likely to have poor oral health-related quality of life as the corresponding "no treatment needed" reference group (odds ratio, 2.74; 95% confidence interval, 1.60-4.59; P0.001). Severe malocclusion is significantly associated with functional limitations, physical pain, and social disability in young adults.Malocclusion is a key factor associated with poor quality of life caused by limited oral function, pain, and social disability in young adults.

The aim of this study was to compare the virtual and manual tooth setups with digital and plaster models in extraction cases by measuring various occlusal parameters and applying the American Board of Orthodontics objective grading system.Linear intra-arch and interarch dimensions (arch width and length, perimeter, overjet, and overbite), angular variables (tip, torque, and rotation), and American Board of Orthodontics objective grading system scores obtained from a digital virtual setup model were compared with those from a plaster model setup.The digital virtual setup model resulted in smaller arch perimeters than did the plaster setup model by 2.20 mm in the maxillary arch (P 0.01) and 1.30 mm in the mandibular arch (P 0.05). The digital virtual setup also exhibited significantly lower values for overbite and overjet (P 0.01). The digital virtual setup had tendencies toward mesial angulation of the anterior teeth, labial inclination of the maxillary anterior teeth (P 0.05), and distal in-rotation of the mandibular teeth (P 0.05). The resulting American Board of Orthodontics objective grading system evaluation showed that larger deductions for overjet, occlusal contact, and total score (P 0.01) were required for the digital than for the manual setup model.Digital and manual setups lead to similar measurements for intra-arch and interarch occlusal variables. However, because of the possibility of collision on proximal and occlusal contact, delicate adjustments in proximal and occlusal contacts are required.

Objective: To compare soft and hard tissue responses based on the degree of maxillary incisor retraction using maximum anchorage in patients with Class II division 1 malocclusion. Materials and Methods: This retrospective study sample was divided into moderate retraction ( Results: There were 2.3 mm and 3.0 mm of upper and lower lip retraction, respectively, in the moderate group; and 4.0 mm and 5.3 mm, respectively, in the maximum group. In the moderate group, the upper lip was most influenced by posterior movement of the cervical point of the maxillary incisor (β = 0.94). The lower lip was most influenced by posterior movement of B-point (β = 0.84) and the cervical point of the mandibular incisor (β = 0.83). Prediction was difficult in the maximum group; no variable showed a significant influence on upper lip changes. The lower lip was highly influenced by posterior movement of the cervical point of the maxillary incisor (β = 0.50), but this correlation was weak in the maximum group. Conclusions: Posterior movement of the cervical point of the anterior teeth is necessary for increased lip retraction. However, periodic evaluation of the lip profile is needed during maximum retraction of the anterior teeth because of limitations in predicting soft tissue responses.

Introduction Several methods are available to enhance the precision of miniscrew placement. The use of surgical guides based on cone-beam computed tomography is indicated especially in patients with risky or difficult anatomic situations. The purpose of this study was to evaluate the accuracy of miniscrew placement by using surgical guides developed with computer-aided design and manufacturing techniques. Methods Miniscrews were placed in cadaver maxillae using stereolithographic computer-aided design and manufacturing techniques with assistance from surgical guides (surgical guide group, n = 25) or periapical x-rays (control group, n = 20). Insertion sites were selected using a 3-dimensional surgical planning program by fusing maxillary digital model images and cone-beam computed tomography images. Deviations between actual and planned placements were measured as 3-dimensional angular deviations and distance (coronal and apical) deviations. Results In the surgical guide group, the angular deviation was a median of 3.14° (range, 1.02°-10.9°), and the mesiodistal deviations in the coronal and apical areas were medians of 0.29 mm (range, 0.03-0.73 mm) and 0.21 mm (range, 0.03-0.97 mm), respectively. The deviations differed significantly between operators in the control group, but not in the surgical guide group. In the surgical guide group, there was no root damage from miniscrew placement, and 84% of the miniscrews were placed without contacting adjacent anatomic structures. In the control group, 50% of the miniscrews were placed between the roots ( P Conclusions Surgical guide accuracy was improved when digital model imaging was used. Miniscrews were placed more accurately when using surgical guides than when using a direct method.

Nongrowing adult patients with skeletal open bite have been considered among the most difficult to treat. This case report describes the surgical-orthodontic treatment of a blind 20-year-old woman who presented with skeletal class II malocclusion with vertical maxillary excess, anterior open bite, and transverse maxillary deficiency.After the transverse maxillary deficiency was corrected with miniscrew-assisted rapid palatal expansion, Le Fort I osteotomy with anterior segmental osteotomy and bilateral sagittal split ramus osteotomy with advancement genioplasty were used to correct the vertical maxillary excess and the anterior open bite. The patient's facial appearance was markedly improved, and she achieved a functional and stable occlusion after these treatments.This case report demonstrates the efficiency of miniscrew-assisted rapid palatal expansion for a patient with transverse maxillary deficiency and the benefit of a team approach using effective orthodontic mechanics in orthognathic surgery to correct a severe dentofacial deformity.

Objective To evaluate transverse skeletal and dental changes, including those in the buccolingual dental axis, between patients with skeletal Class III malocclusion and facial asymmetry after bilateral intraoral vertical ramus osteotomy with and without presurgical orthodontic treatment. Methods This retrospective study included 29 patients with skeletal Class III malocclusion and facial asymmetry including menton deviation > 4 mm from the midsagittal plane. To evaluate changes in transverse skeletal and dental variables (i.e., buccolingual inclination of the upper and lower canines and first molars), the data for 16 patients who underwent conventional orthognathic surgery (CS) were compared with those for 13 patients who underwent preorthodontic orthognathic surgery (POGS), using three-dimensional computed tomography at initial examination, 1 month before surgery, and at 7 days and 1 year after surgery. Results The 1-year postsurgical examination revealed no significant changes in the postoperative transverse dental axis in the CS group. In the POGS group, the upper first molar inclined lingually on both sides (deviated side, -1.8° ± 2.8°, p = 0.044; nondeviated side, -3.7° ± 3.3°, p = 0.001) and the lower canine inclined lingually on the nondeviated side (4.0° ± 5.4°, p = 0.022) during postsurgical orthodontic treatment. There were no significant differences in the skeletal and dental variables between the two groups at 1 year after surgery. Conclusions POGS may be a clinically acceptable alternative to CS as a treatment to achieve stable transverse axes of the dentition in both arches in patients with skeletal Class III malocclusion and facial asymmetry.

OBJECTIVE The aim of this study was to evaluate the skeletal and dentoalveolar changes after miniscrew-assisted rapid palatal expansion (MARPE) in young adults by cone-beam computed tomography (CBCT). METHODS This retrospective study included 14 patients (mean age, 20.1 years; range, 16-26 years) with maxillary transverse deficiency treated with MARPE. Skeletal and dentoalveolar changes were evaluated using CBCT images acquired before and after expansion. Statistical analyses were performed using paired t-test or Wilcoxon signed-rank test according to normality of the data. RESULTS The midpalatal suture was separated, and the maxilla exhibited statistically significant lateral movement (p < 0.05) after MARPE. Some of the landmarks had shifted forwards or upwards by a clinically irrelevant distance of less than 1 mm. The amount of expansion decreased in the superior direction, with values of 5.5, 3.2, 2.0, and 0.8 mm at the crown, cementoenamel junction, maxillary basal bone, and zygomatic arch levels, respectively (p < 0.05). The buccal bone thickness and height of the alveolar crest had decreased by 0.6-1.1 mm and 1.7-2.2 mm, respectively, with the premolars and molars exhibiting buccal tipping of 1.1°-2.9°. CONCLUSIONS Our results indicate that MARPE is an effective method for the correction of maxillary transverse deficiency without surgery in young adults.

The periodontal ligament (PDL) functions as an enthesis, a connective tissue attachment that dissipates strains created by mechanical loading. Entheses are mechanoresponsive structures that rapidly adapt to changes in their mechanical loading; here we asked which features of the PDL are sensitive to such in vivo loading. We evaluated the PDL in 4 physiologically relevant mechanical environments, focusing on mitotic activity, cell density, collagen content, osteogenic protein expression, and organization of the tissue. In addition to examining PDLs that supported teeth under masticatory loading and eruptive forces, 2 additional mechanical conditions were created and analyzed: hypoloading and experimental tooth movement. Collectively, these data revealed that the adult PDL is a remarkably quiescent tissue and that only when it is subjected to increased loads—such as those associated with mastication, eruption, and orthodontic tooth movement—does the tissue increase its rate of cell proliferation and collagen production. These data have relevance in clinical scenarios where PDL acclimatization can be exploited to optimize tooth movement.

The aim of this retrospective cohort study was to investigate the factors contributing to mandibular relapse after intraoral vertical ramus osteotomy (IVRO) while controlling for possible confounders. Forty-seven patients who underwent bimaxillary surgery were divided into three groups according to the direction of horizontal mandibular relapse: a stable group (group S), a posterior relapse group (group P), and an anterior relapse group (group A). Lateral cephalograms were analysed 1 month before and at 7 days and 12 months after surgery. One month before surgery, the pogonion in group A was positioned about 13 mm more anteriorly than in group P (P

In nongrowing patients with skeletal Class II malocclusion, premolar extraction or maxillary molar distalization can be used as camouflage treatment. Orthodontic miniscrew implants are widely used for this purpose because they do not produce undesirable reciprocal effects and do not depend on the patient's cooperation. This article reports on maxillary molar distalization by using miniscrew implants to correct a Class II problem. The main considerations of molar distalization treatment with miniscrew implants are discussed.

In this study, we aimed to determine the effect of bone mineral density (BMD), cortical bone thickness (CBT), screw position, and screw design on the stability of miniscrews.Ninety-six miniscrews of both cylindrical and tapered types were placed in 6 beagle dogs. The BMD and CBT were measured by computerized tomography and correlated with the placement and removal torque and mobility. A regression equation to predict the placement torque was calculated based on BMD, CBT, screw type, and screw position.The placement torque showed a positive correlation in the order of removal torque (0.66), BMD of the cortical bone (0.58), and CBT (0.48). Placement and removal torque values were significantly higher in the mandible compared with the maxilla. Tapered miniscrews had higher placement torque than did the cylindrical type (P0.001). However, the removal torque was similar in both groups. Placement torque was affected by screw position, screw type, and BMD of cortical bone, in that order.BMD of cortical bone, screw type, and screw position significantly influence the primary stability of miniscrews.

Introduction: The purposes of this study were to evaluate the location, nature, and occurrence of incidental findings in maxillofacial structures on 3-dimensional cone-beam volumetric scans done for dental diagnostic purposes and to look for associations between these findings and symptoms in orthodontic patients. Methods: Images from 500 consecutive maxillofacial 3-dimensional scans were examined. The patient sample consisted of 252 orthodontic patients, 172 implant patients, 33 endodontic patients, 34 temporomandibular joint (TMJ) disorder patients, and 10 others. Results: The overall rate of incidental findings was 24.6% (123 patients of 500). The highest rate of incidental findings was in the airway area (18.2%), followed by TMJ findings (3.4%), endodontic findings (1.8%), and others (1.2%). In the orthodontic group, the incidences were airway findings, 21.4%; TMJ findings, 5.6%; and endodontic lesions, 2.3%. Only 22% of the airway findings, such as mucosal thickness, polyps, and retention cysts, were correlated with clinical signs and symptoms. Conclusions: For clinical diagnosis, the data should be interpreted with a full history of clinical signs and symptoms, and with detailed communications with radiological colleagues and other specialists to comprehensively evaluate possible underlying diseases.

Purpose Few studies have evaluated the outcomes of intraoral vertical ramus osteotomy (IVRO) for the correction of skeletal Class III malocclusion with an anterior open bite and the potential for postoperative relapse. Therefore, this study evaluated the stability of outcomes of IVRO for mandibular prognathism with and without an anterior open bite. Material and Methods This retrospective cohort study included consecutive patients with skeletal Class III malocclusion with (AOB group) and without (NAOB group) an anterior open bite who underwent IVRO at Yonsei Dental Hospital (Seoul, Korea). Lateral cephalograms were analyzed for predictor (open bite, yes or no) and outcome (horizontal and vertical relapse in the mandible) variables before and 7 days, 1 year, and 2 years after surgery. Other variables included the patients' demographic characteristics. Data were analyzed using independent t tests, repeated measures analysis of variance, Pearson correlation coefficients, and multiple linear regression analysis. Results The 2 groups (n = 15 each) were matched for baseline demographic characteristics. During the 2-year postoperative period, anterior and superior mandibular movements were observed in the NAOB group, whereas posterior and superior movements were observed in the AOB group. However, there were no meaningful intergroup differences in horizontal and vertical relapses of the mandible at all time points, although the amount of postoperative inferior relapse increased with a decrease in the amount of initial overbite. Conclusions IVRO for the correction of skeletal Class III malocclusion resulted in good postoperative stability over time, regardless of the presence of a preoperative open bite, although the amount of postoperative inferior relapse showed a weak negative correlation with the initial overbite. Thus, IVRO can be a clinically acceptable treatment for skeletal Class III malocclusion with an anterior open bite.

The aim of this study was to evaluate the effect of malocclusion severity on oral health-related quality of life and food intake ability in adult patients, controlling for sex, age, and the type of dental clinic visited.The sample consisted of 472 Korean patients (156 male, 316 female) with a mean age of 21.1 (SD, 8.6) years in a dental hospital and a private clinic. The correlations between the Korean version of the Oral Health Impact Profile-14 (OHIP-14K), subjective food intake ability (FIA) for 5 key foods, and Index of Orthodontic Treatment Need-Dental Health Component (IOTN-DHC) were investigated.The mean IOTN-DHC and OHIP-14K scores were significantly higher for the dental hospital patients than for the private clinic patients (IOTN-DHC, P 0.001; OHIP-14K, P 0.05). Malocclusion severity was significantly higher in male than in female subjects (P 0.001). Older patients perceived their oral health-related quality of life more negatively than did the teens (P 0.001). As the severity of the malocclusion increased, oral health-related quality of life and masticatory function worsened (OHIP-14K, P 0.001; FIA, P 0.05).As the severity of the malocclusion and the age of the patients increased, oral health-related quality of life and masticatory function relatively deteriorated. This finding provides evidence that severe malocclusions are associated with lower quality of life and less masticatory efficiency in older patients.

Implants placed with high insertion torque (IT) typically exhibit primary stability, which enables early loading. Whether high IT has a negative impact on peri-implant bone health, however, remains to be determined. The purpose of this study was to ascertain how peri-implant bone responds to strains and stresses created when implants are placed with low and high IT. Titanium micro-implants were inserted into murine femurs with low and high IT using torque values that were scaled to approximate those used to place clinically sized implants. Torque created in peri-implant tissues a distribution and magnitude of strains, which were calculated through finite element modeling. Stiffness tests quantified primary and secondary implant stability. At multiple time points, molecular, cellular, and histomorphometric analyses were performed to quantitatively determine the effect of high and low strains on apoptosis, mineralization, resorption, and collagen matrix deposition in peri-implant bone. Preparation of an osteotomy results in a narrow zone of dead and dying osteocytes in peri-implant bone that is not significantly enlarged in response to implants placed with low IT. Placing implants with high IT more than doubles this zone of dead and dying osteocytes. As a result, peri-implant bone develops micro-fractures, bone resorption is increased, and bone formation is decreased. Using high IT to place an implant creates high interfacial stress and strain that are associated with damage to peri-implant bone and therefore should be avoided to best preserve the viability of this tissue.

Objectives: To evaluate the initial stability of dual-thread miniscrews by analyzing the strain at the bone-implant interface and insertion torque during implantation in artificial bone models with different cortical bone thicknesses. Materials and methods: Insertion torque, and strain, measured with a five-element strain gauge in 1.0, 1.5, and 2.0-mm artificial cortical bone, during insertion of single- (OAS-T1507) and dual-thread (MPlant-U3) type self-drilling miniscrews were assessed. Results: Both dual- and single-thread miniscrews showed greater than 7790 μstrain for all cortical bone thicknesses, and dual-thread miniscrews reached up to 19580 μstrain in 2.00mm cortical bone. The strain of dual-thread miniscrews increased with increasing cortical bone thicknesses of 1.0–2.0mm. For single-thread miniscrews, the maximum insertion torque was relatively constant, but maximum insertion torque increased significantly in dual-thread groups with increasing cortical bone thicknesses ( P < 0.0001). The maximum insertion torque with all cortical bone thicknesses was significantly lower with single- than dual-thread types ( P < 0.0001). Conclusions: Self-drilling dual-thread miniscrews provide better initial mechanical stability, but may cause strain over the physiological bone remodelling limit at the bone-implant interface in thick cortical bone layers.