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.

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.

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.

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.

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.

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.

Overjet at the anterior and posterior segments: three-dimensional analysis of arch coordination.

OBJECTIVES: To compare the amounts of anatomical overjet measured from facial axis (FA) points with the amounts of bracket overjet measured from bracket slot center (BSC) points. MATERIALS AND METHODS: The samples consisted of 27 subjects with normal occlusion whose models were fabricated with a three-dimensional (3D) scanner and the 3Txer program (Orapix Co Ltd, Seoul, Korea). 3D virtual brackets (0.022'' Slot, MBT setup, 3M Unitek, Monrovia, Calif) constructed with a 3D-CAD program were placed on an FA point with the 3Txer program. The arch dimension and the amounts of overjet from FA and BSC points were measured. Paired t-tests and analysis of variance (ANOVA) tests were used for statistical analysis. RESULTS: No significant difference in arch width and depth was observed between FA and BSC points. Although the amounts of overjet measured from FA points showed homogenous distribution, a tendency to decrease from the anterior segment (2.3 mm) to the posterior one (2.0 mm) was noted. However, the amounts of overjet measured from BSC points were variable, especially in the premolar and molar areas. Significant discrepancies in the amounts of overjet in most of the areas between FA and BSC points (more than P < .05), except the lower second premolar and second molar areas, were reported, even though insets and offsets are part of the prescription for the base of straight-wire appliance (SWA) brackets. CONCLUSIONS: The hypotheses that the amount of overjet measured from BSC points was 3 mm through the whole segments and that distribution of the amounts of overjet from BSC points was the same as that from FA points were rejected.

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.

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.

Application of the foramina of the trigeminal nerve as landmarks for analysis of craniofacial morphology.

OBJECTIVE: The objective of this study was to develop new parameters based on the foramina of the trigeminal nerve and to compare them with the conventional cephalometric parameters in different facial skeletal types. METHODS: Cone-beam computed tomography (CBCT) scans and cephalograms from 147 adult patients (57 males and 90 females; mean age, 26.1 years) were categorized as Class I (1° < ANB < 3°), Class II (ANB > 5°), and Class III (ANB < -1°). Seven foramina in the craniofacial area-foramen rotundum (Rot), foramen ovale (Ov), infraorbital foramen, greater palatine foramen, incisive foramen (IF), mandibular foramen (MDF), and mental foramen (MTF)-were identified in the CBCT images. Various linear, angular, and ratio parameters were compared between the groups by using the foramina, and the relationship between the new parameters and the conventional cephalometric parameters was assessed. RESULTS: The distances between the foramina in the cranial base did not differ among the three groups. However, the Rot-IF length was shorter in female Class III patients, while the Ov-MTF length, MDF-MTF length, and Ov-MDF length were shorter in Class II patients than in Class III patients of both sexes. The MDF-MTF/FH plane angle was larger in Class II patients than in Class III patients of both sexes. Most parameters showed moderate to high correlations, but the Ov-MDF-MTF angle showed a relatively low correlation with the gonial angle. CONCLUSIONS: The foramina of the trigeminal nerve can be used to supplement assessments based on the conventional skeletal landmarks on CBCT images.

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.

Time and pattern of the fusion of the spheno-occipital synchondrosis in patients with skeletal Class I and Class III malocclusion.

OBJECTIVES: To investigate the time and pattern of fusion of the spheno-occipital synchondrosis in patients with skeletal Class I and Class III malocclusion using cone-beam computed tomography (CBCT). MATERIALS AND METHODS: A total of 262 CBCT images were collected: 140 skeletal Class I (0° < ANB < 4°; 71 males, 69 females) and 122 skeletal Class III (ANB ≤ 0°; 61 males and 61 females). The fusion stages were identified using CBCT images of a six-stage system defined by the appearance of osseous cores and ossifying vestige in the synchondrosis. The age distributions of each stage and the pattern of fusion were evaluated. RESULTS: The stages of fusion progressed with increasing age (P < .05, r = .824), and the age distributions in the female groups were generally 1 to 3 years younger than those in the male groups. However, no significant differences were observed between the skeletal Class I and Class III groups regarding the time of ossification of the synchondrosis. The osseous cores appeared most frequently in the supero-center part, followed by the mid-center part of the synchondrosis. CONCLUSIONS: The time and pattern of fusion of the spheno-occipital synchondrosis are not apparently different between patients with Class I malocclusion and those with Class III malocclusion. The osseous cores appear frequently in the supero-center and mid-center of the synchondrosis with various patterns before the end of the pubertal growth spurt period.

Botulinum toxin-A injection into the anterior belly of the digastric muscle for the prevention of post-operative open bite in class II malocclusions: a case report and literature review.

BACKGROUND: Class II malocclusion patients with hyperdivergent facial types are characterized by short mandibular body lengths and anterior open bite. Accordingly, the treatment for hyperdivergent skeletal class II malocclusion is a lengthening of the mandibular body length and a counterclockwise rotation of the mandible. To prevent post-operative relapse, botulinum toxin-A (BTX-A) injection can be a retention modality. CASE PRESENTATION: A class II open-bite patient received BTX-A injection to the anterior belly of her digastric muscle for the prevention of post-operative relapse. The relapse was evaluated via a clinical examination and a lateral cephalometric radiograph after the completion of post-surgical orthodontic treatment. The patient showed stable occlusion without any signs of relapse at 15 months post-operatively. CONCLUSION: In this case presentation, a single injection into the anterior belly of the digastric muscle was sufficient for the prevention of post-operative open bite.

Application of Enamel Matrix Derivative and Intrusive Orthodontic Movement in the Treatment of Vertical Bony Defects: A Case Report.

This case report presents treatment of a severe localized horizontal bone loss combined with infrabony defects adjacent to pathologically migrated teeth by orthodontic intrusion following a graft of enamel matrix derivative (EMD) without root surface conditioning. The patient was diagnosed with Angle Class II malocclusion, anterior spacing, and pathologically migrated incisors. Graft of EMD mixed with bone materials was applied for periodontal regeneration before orthodontic treatment, and periapical radiographs were taken every 3 months for radiographic evaluation. After closure of anterior spaces by orthodontic treatment, infrabony defects improved dramatically, with a favorable alveolar bone level and periodontal pocket depth.

Soft tissue thickness for placement of an orthodontic miniscrew using an ultrasonic device.

OBJECTIVES: To evaluate area- and gender-related differences in the soft tissue thickness of potential areas for installing miniscrews in the buccal-attached gingiva and the palatal masticatory mucosa. MATERIALS AND METHODS: The sample consisted of 61 Korean young adults. An ultrasonic gingival-thickness meter was used to measure the soft-tissue thickness in the buccal-attached gingiva just adjacent to the mucogingival junction of the upper and lower arches and 4 mm and 8 mm below the gingival crest in the palatal masticatory mucosa. Independent t-test, paired t-test, and one-way analysis of variance were used for statistical analysis. RESULTS: Buccal-attached gingiva thickness in the upper arch was significantly greater in men than in women, but buccal-attached gingiva thickness in the lower arch and palatal masticatory mucosa thickness 4 and 8 mm below the gingival crest did not show gender differences. Significantly thicker soft tissue occurred in the anterior areas in the upper arch and in the posterior areas in the lower arch. In the palatal masticatory mucosa, significantly thicker soft tissue was found 4 mm below the gingival crest in the anterior areas and 8 mm below the gingival crest in the posterior areas. The areas between the canines and the premolars showed higher values than other areas 4 mm below the gingival crest. However, the soft-tissue thickness 8 mm below the gingival crest showed a progressive increase from the anterior to the posterior areas. CONCLUSION: Measurements of the soft-tissue thickness using an ultrasonic device could help practitioners select the proper orthodontic miniscrew in daily clinical practice.