A comparison of maxillary posterior changes following facemask therapy: Skeletal anchorage versus tooth-borne anchorage.

OBJECTIVE: To compare changes in the maxillary posterior structure as seen in cone-beam computed tomography (CBCT) images resulting from facemask therapy using skeletal (miniplate/FM) anchorage versus tooth-borne anchorage (RME/FM). MATERIALS AND METHODS: A retrospective study was conducted on 20 patients divided into the miniplate/FM group (nine patients aged 9.5 ± 1.4 years) and the RME/FM group (11 patients aged 9.2 ± 1.4 years). CBCT images before and after facemask therapy were evaluated to assess changes in the maxillary posterior structure. RESULTS: The miniplate/FM group had greater advancement of the maxilla and midface compared to the RME/FM group (p < .05). Specifically, there was about three times more advancement of the pterygomaxillary suture in the miniplate/FM group than in the RME/FM group (p < .05). Moreover, the advancement of the pterygomaxillary suture was about half the advancement of A point in the miniplate/FM group, while only about 25% in the RME/FM group. Finally, the miniplate/FM group showed an increase in the transverse dimension of the posterior and superior parts of the maxilla (p < .05). CONCLUSION: There was greater forward movement of the pterygomaxillary suture with facemask therapy using the skeletal anchorage compared to tooth-borne anchorage, leading to a more significant advancement of the maxilla and midface.

Facemask therapy with skeletal anchorage: A possible alternative to orthognathic surgery.

Treatment of skeletal Class III malocclusion in young patients is very challenging. Facemask therapy has been proven to be effective in early correction of Class III malocclusion. With the aid of skeletal anchorage, the orthopaedic effects are expected to be greater than the effects with conventional facemask with tooth-borne anchorage. However, only a few studies have reported on the long-term stability of facemask therapy combined with skeletal anchorage. This report examines two patients with skeletal Class III malocclusion who were treated with facemask and skeletal anchorage followed by orthodontic treatment using fixed orthodontic appliances. The long-term effects of facemask therapy with skeletal anchorage are discussed and compared with the conventional facemask therapy.

Porous TiO2 Nanotube Arrays for Drug Loading and Their Elution Sensing.

Porous TiO2 nanotube arrays have been attracting much attention as optical sensing layers and surface layers of dental implants because they are stable in acid and biocompatible. To use them as the optical sensing layers, TiO2 nanotube arrays with various structures were fabricated and obtained an optimized microstructure at 50 V, 50 min and 0.5 wt% of NH4F, 7.4 vol% deionized water in ethylene glycol. TiO2 nanotube arrays which had diameters of ~73.54 nm and lengths of ~3.39 µm showed the best sensing performance. A Ti implant was also anodized at 60 V for 4 hr in an ethylene glycol electrolyte and TiO2 nanotube arrays showed the pore diameter of 156.01 nm and the thickness of 6.87 µm. Recombinant human bone morphogenetic protein-2 (rhBMP-2), isobutylphenyl propionic acid, and sodium alendronate were loaded into the TiO2 nanotube arrays on the surface of the Ti implant. For elution of these drugs, optical thickness changes of 2.4 nm, 3.5 nm and 3.1 nm were respectively observed for about 2.2 hr, 3.6 hr and 3.1 hr. The TiO2 nanotube arrays were useful for drug loading and their elution interferometric sensing.

Botulinum Toxin Injection to Treat Masticatory Movement Disorder Corrected Mandibular Asymmetry in a Growing Patient.

An 8-year-old girl with masticatory movement disorder received botulinum toxin-A (BTX-A) injection and orthodontic treatment. She showed facial asymmetry with right masseter muscle hyperplasia. After BTX-A injection combined with orthodontic treatment, the transverse discrepancy between right and left maxillary dentition completely corrected. Cone-beam computed tomography images revealed that the height of the left mandibular ramus had increased by 2.3 mm, considerably more than on the right side, the discrepancy in mandibular ramus height between the left and the right decreased dramatically. In a short period, BTX-A injection combined with orthodontic treatment corrected a mandibular movement disorder with asymmetric mandibular growth in a growing patient.

Effect of drug-loaded TiO2 nanotube arrays on osseointegration in an orthodontic miniscrew: an in-vivo pilot study.

Osseointegration was evaluated for the surface of miniscrews with TiO2 nanotube arrays containing drugs in this in-vivo study. The diameter and length of the TiO2 nanotube arrays were about 70 nm and 5 µm, respectively. Recombinant human bone morphogenetic protein-2 (rhBMP-2) or ibuprofen was loaded in the TiO2 nanotube arrays with 12 miniscrews. The 12 drug-loaded miniscrews, 6 miniscrews with no drug-loaded TiO2 nanotube arrays and 6 conventional miniscrews, were placed on the tibias of New Zealand white rabbits. Histological osseointegration was assessed 8 weeks after implantation by measuring the bone-to-implant contact (BIC) ratio. Ibuprofen-loaded miniscrews showed a significantly higher BIC of 71.6% over conventional miniscrews of 44.3% on average. The mean BIC ratios of rhBMP-2-loaded miniscrews and no drug-loaded miniscrews was 24.6% and 60.1%, respectively. Our results suggest that TiO2 nanotube arrays on the surface of miniscrews could be used as carriers of drugs, and loading ibuprofen in TiO2 nanotube arrays may improve osseointegration of miniscrews. However, the effect of rhBMP-2 loaded in TiO2 nanotube arrays on osseointegration of miniscrews was questionable in this pilot study.

Effect of TiO2 nanotubes arrays on osseointegration of orthodontic miniscrew.

To increase the stability of orthodontic miniscrews, TiO2 nanotube arrays were fabricated on the surface of Ti miniscrews and the effect of those arrays on the osseointegration of miniscrews was evaluated. Highly ordered TiO2 nanotube arrays were grown on the surface of orthodontic miniscrews. Ethylene glycol based electrolyte was used in the anodic oxidation process. Two-step anodic oxidation was conducted to obtain clean and open windows in TiO2 nanotube arrays. The diameter and length of the TiO2 nanotube arrays were ~ 70 nm and ~ 5 µm, respectively. The miniscrews with TiO2 nanotube arrays were implanted in the legs of New Zealand white rabbits for 8 weeks. Histological osseointegration was assessed by bone-to-implant contact ratio, and three-dimensional bone volume ratio was measured by micro-computed tomography analysis. The miniscrews with TiO2 nanotube arrays had a greater mean bone-to-implant contact ratio of 52.8 % than the control, 29.3 %. Mean bone volume ratio (BV/TV) was also higher in the miniscrews with TiO2 nanotube arrays, at 81.2 % than those in the control via micro-CT analysis. Our findings support that TiO2 nanotube arrays on the surface of miniscrews enhance osseointegration and improve the stability of the miniscrew.

Changes in natural head position after orthognathic surgery in skeletal Class III patients.

INTRODUCTION: The purpose of this study was to evaluate the change in natural head position (NHP) after orthognathic surgery in skeletal Class III patients. METHODS: We used pretreatment (T1) and posttreatment (T2) cephalometric radiographs and T1 and T2 lateral facial photographs of 20 skeletal Class III patients (mean age, 21.6 years), with 20 skeletal Class I patients (mean age, 22.2 years) as the controls. The Class III patients had undergone mandibular setback surgery, and the patients in the control group had received conventional orthodontic treatment. All lateral facial photographs were recorded in NHP. The true vertical line (TVL) was transferred from the photograph to the cephalometric radiograph, and then the angle between the TVL and the Frankfort horizontal plane (TVL/FH) was measured. A t test and a paired t test were used to verify the differences between the 2 groups, and between the T1 and T2 measurements in each group. RESULTS: The mean TVL/FH at T1 was significantly greater in the Class III group than in the Class I group; this indicated that the Class III group showed head flexion. However, the mean TVL/FH of the Class III group decreased by -3.1° at T2; this indicated head extension, and it did not significantly differ from that of the Class I group. Nineteen of the 20 Class I patients showed minimal or no change in their TVL/FH (-1.5° to 1.5°) at T2. On the other hand, 6 of the 20 Class III patients showed more than a 4.5° decrease in their TVL/FH at T2. CONCLUSIONS: Most of the Class I patients showed minimal or no change in their NHP at T2, but some Class III patients had changes in their NHP that tended toward head extension after mandibular setback surgery. Thus, soft tissue analysis using the TVL in NHP may not be reliable for some skeletal Class III patients who undergo mandibular setback surgery.

Effects of 4-hexylresorcinol on facial skeletal development in growing rats: Considerations for diabetes.

Objective: : To investigate the long-term effects of 4-hexylresorcinol (4HR) on facial skeletal growth in growing male rats, with a focus on diabetic animal models. Methods: : Forty male rats were used. Of them, type 1 diabetes mellitus was induced in 20 animals by administering 40 mg/kg streptozotocin (STZ), and they were assigned to either the STZ or 4HR-injected group (STZ/4HR group). The remaining 20 healthy rats were divided into control and 4HR groups. We administered 4HR subcutaneously at a weekly dose of 10 mg/kg until the rats were euthanized. At 16 weeks of age, whole blood was collected, and micro-computed tomography of the skull and femur was performed. Results: : All craniofacial linear measurements were smaller in the STZ group than in the control group. The mandibular molar width was significantly smaller in the 4HR group than in the control group (P = 0.031) but larger in the STZ/4HR group than in the STZ group (P = 0.011). Among the diabetic animals, the STZ/4HR group exhibited significantly greater cortical bone thickness, bone mineral density, and bone volume than the STZ group. Serum testosterone levels were also significantly higher in the STZ/4HR group than in the STZ group. Conclusions: : 4HR administration may have divergent effects on mandibular growth and bone mass in healthy and diabetic rats. In the context of diabetes, 4HR appears to have beneficial effects, potentially through the modulation of mitochondrial respiration.

Crown-root angulations of the maxillary anterior teeth according to malocclusions: A cone-beam computed tomography study in Korean population.

Objective: To compare crown-root angulations of the permanent maxillary anterior teeth in skeletal Class I, Class II, and Class III Korean malocclusion patients using cone-bean computed tomography (CBCT) images. Methods: Sixty CBCT images were collected from orthodontic patients archive based on skeletal Class I (0˚< A point-nasion-B point angle [ANB] < 4˚), Class II (ANB ≥ 4˚), and Class III (ANB ≤ 0˚) to have 20 samples in each group. Mesiodistal crown-root angulation (MDCRA) and labiolingual crown-root angulation (LLCRA) were evaluated after orientation of images. Crown-root angulations were compared among Class I, Class II, and Class III groups and among the maxillary anterior teeth in each group. Results: LLCRAs of the maxillary central incisor and the lateral incisor were significantly lower in Class III group than those in Class I group. However, those of the canine showed no significant differences among groups. MDCRAs of the maxillary anterior teeth did not significantly differ among groups either. Conclusions: Our results suggest that skeletal Class III malocclusion might affect LLCRA of the maxillary incisors, especially the central incisor.

Camouflage treatment by backward rotation of the mandible for a severe skeletal Class III malocclusion with aplastic anemia: A case report.

Orthognathic surgery is the primary treatment option for severe skeletal discrepancy. However, orthodontic camouflage should be considered as an alternative treatment option, considering the risks of surgery. A 19.5-year-old man presented with a severe prognathic mandible with a Class III molar relationship and an anterior crossbite. Orthognathic surgery could be considered because of his severe skeletal discrepancy and mandibular prognathism. However, the anesthetist for orthognathic surgery did not recommend surgery under general anesthesia because of risk factors associated with the patient's aplastic anemia, including bleeding and infections. Thus, a camouflage treatment to promote backward rotation of the mandible via orthodontic extrusion of the posterior teeth was planned. An anterior bite plate, intermaxillary elastics, and fixed orthodontic appliances were used to extrude the posterior teeth and to align the dentition. After 17 months of nonsurgical orthodontic treatment, normal occlusion was achieved, and the facial profile was dramatically improved. This case report describes the dentoskeletal and soft-tissue effects of mandibular rotation and its long-term stability.

Comparison of facemask therapy effects using skeletal and tooth-borne anchorage.

OBJECTIVES: To investigate long-term outcomes of dentoskeletal changes induced by facemask therapy using skeletal anchorage in Class III patients and compare them to those of conventional tooth-borne anchorage. MATERIALS AND METHODS: This retrospective study included 20 patients who received facemask (FM) therapy with miniplates as anchorage for maxillary protraction (Miniplate/FM group, 10.6 ± 1.1 years old [mean ± SD]) and 23 patients who were treated with facemask with rapid maxillary expander (RME/FM group, 10.0 ± 1.5 years old [mean ± SD]). Dentoskeletal changes were evaluated using lateral cephalograms at pretreatment (T1), after facemask therapy (T2), and at the post-pubertal stage (T3). Cephalometric changes were compared between groups and clinical success rates at T3 were evaluated. RESULTS: SNA and A to N perpendicular to FH increased significantly more in the Miniplate/FM group than in the RME/FM group when comparing short-term effects of facemask therapy (T1-T2). ANB, Wits appraisal, Angle of convexity, mandibular plane angle, and overjet decreased significantly more in the RME/FM group than in the Miniplate/FM group after facemask therapy (T2-T3). A more favorable intermaxillary relationship was observed in the Miniplate/FM group than in the RME/FM group in long-term observations (T1-T3). Clinical success rate at T3 was 95% in the Miniplate/FM group and 85% in the RME/FM group. CONCLUSIONS: Facemask therapy with skeletal anchorage showed a greater advancement of the maxilla and more favorable stability for correction of Class III malocclusion in the long-term than conventional facemask therapy with tooth-borne anchorage.

Maxillary protraction with miniplates providing skeletal anchorage in a growing Class III patient.

Maxillary protraction headgear has been used in the treatment of Class III malocclusion with maxillary deficiency. However, loss of dental anchorage has been reported with tooth-borne anchorage such as lingual arches and expansion devices. This side effect can be minimized with skeletal anchorage devices such as implants, onplants, mini-implants, and miniplates. The use of miniplates for maxillary protraction in the mixed dentition has not been reported in the literature. This case report describes the treatment of an 8-year-old girl with a Class III malocclusion and maxillary deficiency. Miniplates were used as skeletal anchorage for maxillary protraction followed by phase 2 orthodontic treatment with fixed appliances. Skeletal, dental, and facial changes in response to orthopedic and orthodontic treatment are reported to illustrate the esthetics, function, and stability of treatment with this new technique.

Relationship between the lingual frenulum and craniofacial morphology in adults.

INTRODUCTION: The purpose of this study was to determine the relationship between the length of the lingual frenulum and craniofacial morphology and test the hypothesis that skeletal Class III malocclusion is related to tongue-tie, in which the lingual frenulum is short and restricts the mobility of the tongue. METHODS: The sample consisted of 50 skeletal Class I patients (0° < ANB angle < 4°), 50 skeletal Class II patients (ANB angle > 4°), and 50 skeletal Class III patients (ANB angle <0°). Direct and indirect measuring methods were used to quantify the length of the lingual frenulum. The median lingual frenulum length was measured directly with a lingual frenulum ruler. It was evaluated indirectly by measuring the differences between the maximum mouth opening with and without the tip of the tongue touching the incisive papilla. A lateral cephalogram was taken for each subject and a computerized cephalometric analysis was used to assess the cranial morphology. Analysis of variance (ANOVA) was used to compare the differences among the 3 groups. The Pearson correlation analysis was used to detect any relationship between the lingual frenulum length and cephalometric variables. RESULTS: The median lingual frenulum length was significantly longer in the skeletal Class III subjects compared with the skeletal Class I and Class II subjects. The maximum opening of the mouth was significantly reduced in the skeletal Class III subjects compared with Class I and Class II subjects. Significant correlations were also found among the median lingual frenulum length, maximum mouth opening reduction, and the cephalometric variables such as the SNB and ANB angles, Wits appraisal, mandibular length, and the interincisal angle. CONCLUSIONS: The present study supports the hypothesis that skeletal Class III malocclusion is related to long median lingual frenulum or a tongue-tie tendency. Patients diagnosed with tongue-tie might have a tendency toward skeletal Class III malocclusion.

Surgery-first approach reduces the overall treatment time without damaging long-term stability in the skeletal class III correction: a preliminary study.

BACKGROUND: Compared to the conventional approach, including preoperative orthodontic preparation, the so-called surgery-first approach (SFA) seems to reduce the overall treatment time in the correction of skeletal class III dentofacial deformity. However, there have been controversies about postoperative skeletal stability with SFA. Therefore, we investigated the long-term stability and the overall treatment time after maxillomandibular surgery for skeletal class III correction with or without preoperative orthodontic preparation. METHODS: This retrospective study included eight patients who underwent maxillomandibular surgery for class III correction with the SFA (SFA group) and 20 patients who underwent the conventional approach (CA group). A comparative study of the change in the maxillary and mandibular position on preoperative (T1), 1-day (T2), 6-month (T3), and 2-year (T4) postoperative lateral cephalograms. We calculated the overall treatment time for each group. RESULTS: At the presurgical stage (T1), there was no bias in the skeletal features between the two groups. In the surgical change from T1 to T2, the mandible (point B) of the CA group was significantly moved superiorly. Short-term changes from T2 to T3 revealed that the mandible moved forward in both groups, whereas the maxillary position showed no significant changes. Long-term changes from T3 to T4 demonstrated that none of the measured parameters showed any significant differences. Finally, the average of overall treatment time was 15.1 months in the SFA group and 26.0 months in the CA group. CONCLUSIONS: These findings suggest that SFA in bimaxillary orthognathic surgery for skeletal class III correction leads to predictable long-term skeletal stability, similar to surgery with CA. Furthermore, SFA reduced the overall treatment time compared to CA.

An in vivo 3D micro-CT evaluation of tooth movement after the application of different force magnitudes in rat molar.

OBJECTIVE: To investigate the precise longitudinal change in the periodontal ligament (PDL) space width and three-dimensional tooth movement with continuous-force magnitudes in living rats. MATERIALS AND METHODS: Using nickel-titanium closed-coil springs for 28 days, 10-, 25-, 50-, and 100-g mesial force was applied to the maxillary left first molars. Micro-CT was taken in the same rat at 0, 1, 2, 3, 10, 14, and 28 days. The width of the PDL was measured in the pressure and tension sides from 0 to 3 days. Angular and linear measurements were used to evaluate molar position at day 0, 10, 14, and 28. The finite element model (FEM) was constructed to evaluate the initial stress distribution, molar displacement, and center of rotation of the molar. RESULTS: The initial evaluation of PDL width showed no statistical differences among different force magnitudes. Tooth movement was registered 1 hour after force application and gradually increased with time. From day 10, greater tooth movement was observed when 10 g of force was applied. The FEM showed that the center of rotation in the molar is located in the center of five roots at the apical third of the molar roots. CONCLUSION: The rat's molar movement mainly consists of mesial tipping, extrusion of distal roots, intrusion of mesial root, palatal inclination, and mesial rotation. Although the initial tooth movement after the application of different force magnitudes until day 3 was not remarkably different, 10 g of force produced more tooth movement compared with heavier forces at day 28.

A novel method for the assessment of three-dimensional tooth movement during orthodontic treatment.

OBJECTIVE: To (1) evaluate the stability of palatal rugae as landmarks for superimposition of dental casts and (2) establish a three-dimensional superimposition method of maxillary dental casts for analyzing orthodontic tooth movement. MATERIALS AND METHODS: The sample consisted of dental casts obtained from 10 patients treated with extraction of bilateral maxillary first premolars and placement of three palatal miniscrews as anchorage for retraction of the anterior teeth. Dental casts were measured by means of laser surface scanning system, and three-dimensional images were reconstructed. Serial dental casts were superimposed on the three miniscrews as registration landmarks (miniscrew-superimposition method), and the displacement of each palatal ruga point during the closure of extraction spaces was measured. Displacement of the central incisors was measured by the miniscrew-superimposition method and the proposed superimposition technique (ruga-palate-superimposition method). Correlation analysis and paired t-tests were performed to determine whether a significant difference existed between the measurements of the two superimposition methods. RESULTS: The medial points of the third palatal rugae and the shape of the palatal vault were stable throughout the treatment. The displacement of the central incisors measured using the ruga-palate-superimposition method showed no significant difference with that measured using the miniscrew-superimposition method. CONCLUSION: The maxillary dental casts can be reliably superimposed on the medial points of the third palatal rugae and the palatal vault as reference landmarks.

An M-CSF receptor c-Fms antibody inhibits mechanical stress-induced root resorption during orthodontic tooth movement in mice.

OBJECTIVE: To examine the effect of anti-c-Fms antibody on odontoclastogenesis and root resorption in an orthodontic tooth movement mouse model. MATERIALS AND METHODS: We used orthodontic tooth movement in which an Ni-Ti coil spring was inserted between the upper incisors and the upper first molar. Root resorption occurred in this model. Anti-c-Fms antibody was injected daily into a local site for 12 days during mechanical loading. Odontoclastogenesis and root resorption were assessed by histology and scanning electron microscopy. RESULTS: The anti-c-Fms antibody significantly inhibited odontoclastogenesis and root resorption during orthodontic tooth movement. CONCLUSION: M-CSF and/or its receptor is a potential therapeutic target in mechanical stress- induced odontoclastogenesis, and injection of an anti-c-Fms antibody might be useful for inhibition of mechanical stress-induced root resorption during orthodontic tooth movement.

Microbiologic changes in subgingival plaque after removal of fixed orthodontic appliances.

OBJECTIVE: To evaluate changes that occur in the subgingival microbiota after removal of fixed orthodontic appliances using polymerase chain reaction (PCR). MATERIALS AND METHODS: Thirty orthodontic patients (11 males and 19 females; aged 20 +/- 7.3 yr) were included in this study. Subgingival plaque samplings were gathered from the disto-buccal gingival crevice of the left upper central incisors and the left lower central incisors, and from the mesio-buccal gingival crevice of the left upper first molars and the left lower first molars, at two different times: 2 weeks before appliance removal (T1), and 3 months after appliance removal (T2). DNA was extracted from the samples and the 16S rRNA-based PCR detection method was used to determine the prevalence of Actinobacillus actinomycetemcomitans , Tannerella forsythia , Campylobacter rectus , Eikenella corrodens , Porphyromonas gingivalis , Prevotella intermedia , Prevotella nigrescens , and Treponema denticola , which are considered as putative periodontopathogens. RESULTS: The frequency of positive sites at T1 and T2 was 65% and 43.3% for C. rectus , and 53.3% and 30.8% for E. corrodens , respectively. For the other bacteria, the frequency tended to be reduced between times. CONCLUSION: Periodontopathogens during orthodontic treatment were significantly reduced within 3 months of appliance removal. However, how long it takes to return to the preorthodontic composition of the subgingival microbiota and whether it happens at all remain to be seen.

Botulinum toxin A injection into the anterior belly of the digastric muscle increased the posterior width of the maxillary arch in developing rats.

BACKGROUND: The purpose of this study was to evaluate the effects of botulinum toxin A (BTX) injection into the anterior belly of the digastric muscle on a growing rat. METHODS: Ten Sprague Dawley rats were used in this study. When the rats were 13 days old, 0.5 units of BTX was injected into the anterior belly of the digastric muscle for the experimental group (n = 5). For the control, the same volume of normal saline was injected (n = 5). The rats were sacrificed at 60 days old, and the skulls were harvested for micro-computed tomography (µCT) analysis. RESULTS: In anthropometric analysis, the zygomatic arch and mandibular bi-condylar width were significantly lower in the experimental group than those in the control group (P = 0.025 and 0.027, respectively). The maxillary point width was significantly higher in the experimental group than that in the control group (P = 0.020). CONCLUSION: BTX injection into the anterior belly of the digastric muscle had effects on the maxillofacial bony width in growing rats.

Pierre Robin sequence with severe scoliosis in an adult: A case report of clinical and radiological features.

Pierre Robin sequence (PRS) is characterized by the triad of micrognathia, glossoptosis, and airway obstruction. PRS does not have a single pathogenesis, but rather is associated with multiple syndromes. This report presents the case of a 35-year-old woman with PRS and scoliosis. Among the syndromes related to PRS, cerebro-costo-mandibular syndrome (CCMS), which is characterized by posterior rib gap defects and vertebral anomalies, was suspected in this patient. However, no posterior rib gap defect was detected on radiological examinations. Although over 80 cases of CCMS have been reported to date, few cases of PRS with scoliosis alone have been reported. Therefore, this report demonstrated the clinical, radiological, and cephalometric characteristics of an adult patient with PRS and scoliosis, but without rib anomalies.