单侧完全性唇腭裂术后患者牙弓间宽度不调的矫治

目的　通过对单侧完全性唇腭裂术后患者上下颌间牙弓宽度不调的研究及对患者正畸治疗的临床观察 ,总结该类患者正畸治疗的特点。方法　对 4 8例单侧完全性唇腭裂术后患者进行临床检查 ,记录其上下牙弓间的宽度关系 ;根据患者错情况制定不同的治疗方案进行临床治疗。结果　 (1)单侧完全性唇腭裂术后患者中出现上下颌牙弓宽度不调的比率为 6 0 .4 % ,双侧后牙反为 33.3% ,单侧后牙反为 16 .7%。男女之间差异无显著性。 (2 )宽度不调以双尖牙区为重 ,上尖牙区是扩弓治疗的重点。 (3)磨牙区牙弓宽度的不协调常较轻微 ,一些患者甚至上颌最后磨牙区略宽 ,对 5例患者 (占 10 4 % )进行了上颌磨牙的腭向移动。结论　单侧完全性唇腭裂患者正畸治疗中上颌多需扩弓 ,且扩弓潜力较大。对于严重拥挤的患者 ,拔牙决定应在扩弓后作出。扩弓治疗应在牙槽突植骨前进行 ,扩弓后需延长保持时间     

Bone anchor systems for orthodontic application: a systematic review

This systematic review was performed to investigate the usefulness and clinical effectiveness of skeletal anchorage devices to determine the most effective bone anchor system for orthodontic tooth movement. Literature on bone anchorage devices was selected from PubMed and the Cochrane Library from January 1966 to June 2010. 55 publications regarding miniplates, miniscrews, palatal implants and dental implants as orthodontic anchorage were identified for further analysis. All bone anchorage devices were found to have relatively high success rates and demonstrated their ability to provide absolute anchorage for orthodontic tooth movement. Significant tooth movement could be achieved with low morbidities and good patient acceptance. The reported success rates for the four groups of anchorage systems were generally high with slight variability (miniplates 91.4–100%; palatal implants 74–93.3%; miniscrews 61–100%; dental implants 100%). It was concluded that bone anchorage systems can achieve effective orthodontic movement with low morbidities. The success rate is generally high with slight variability between miniplates, palatal implants, miniscrews and dental implants. Owing to the lack of randomized controlled trials, there is no strong evidence to confirm which bone anchor system is the most effective for orthodontic tooth movement.     

种植钉辅助上颌快速扩弓治疗年轻成人上颌牙弓狭窄的CBCT分析

目的 探讨种植钉辅助上颌快速扩弓治疗年轻成人上颌狭窄的效果.方法 样本包括15.5～28.0岁上颌骨性狭窄病例10例(男3例,女7例),平均年龄(20.1±5.4)岁.使用种植钉辅助上颌快速扩弓技术,分别于治疗前、扩弓后和保持3个月后拍摄CBCT,并对资料进行统计分析.结果 扩弓后腭中缝前部和后部分别增加3.49 mm和2.94 mm,后部腭中缝增量占扩弓器扩大量的47.9％,后部腭中缝增量占第一磨牙间宽度增量的52.3％.鼻腔宽度、上颌基骨和牙槽宽度扩弓后增加(P＜0.05),且保持三个月后增加量无明显改变.牙槽骨高度变化无统计学意义(P＞0.05).结论 种植钉辅助上颌快速扩弓能有效开展年轻成人腭中缝,矫正骨性牙弓狭窄,并减少牙支抗扩弓引起的副作用.     

Skeletal and dentoalveolar changes in the transverse dimension using microimplant-assisted rapid palatal expansion (MARPE) appliances

Conventional rapid palatal expansion (RPE) has been proven to be a reliable treatment for correcting transverse maxillary deficiency in young patients. However, side effects including dental tipping and risk of periodontal problem limited its application to young patients after the pubertal growth spurt. Surgically assisted rapid palatal expansion (SARPE), a supplement to RPE, could be applied in skeletally mature patients. However, SARPE was an invasive method, and the morbidity, risks and cost related to surgical treatment might discourage many adult patients. The use of Microimplant-Assisted Rapid Palatal Expansion (MARPE) appliance, which can potentially avoid surgical intervention, is gaining popularity in treatment of maxillary transverse deficiency (MTD) in young adolescent patients. However, the literature on the skeletal and dentoalveolar changes with this appliance is scarce. To evaluate the immediate skeletal and dentoalveolar changes in the transverse dimension with the maxillary skeletal expander (MSE), a MARPE appliance with hybrid anchorage, using cone-beam computed tomography (CBCT). Twenty-two patients (11 males and 11 females, mean age 14.97 ± 6.16 years) with transverse maxillary deficiency were treated using the MSE (Biomaterials Korea, Inc., Seoul, Korea). The appliance consisted of a central expansion screw that were welded to four tubes that served as guides for microimplant placement. The microimplants were 1.8 mm in diameter and 11 mm in length. The longer length of microimplants permitted bicortical engagement of the palatal and nasal floor, reducing the force transmitted to the anchored teeth during expansion. The appliance activation varied with age and skeletal maturity of the patient. The expansion was terminated when 2–3 mm of overexpansion was achieved. CBCT scans were taken before treatment (T1) and immediately after expansion (T2). Measurements were taken to evaluate the amount of total expansion, skeletal expansion, and angular dental tipping at the first molar region. A total expansion of 5.41 ± 2.18 mm was achieved, 59.23 ± 17.75% of which was attributed to skeletal expansion (3.15 ± 1.64 mm) with the first molars exhibiting buccal tipping of 2.56 ± 2.64°. The use of MARPE appliances such as MSE can be used to correct transverse maxillary deficiency in adolescent patients with minimal dentoalveolar side effects.     

Comparison of skeletal maxillary transverse deficiency treated by microimplant-assisted rapid palatal expansion and tooth-borne expansion during the post-pubertal growth spurt stage:: A prospective cone beam computed tomography study

ObjectiveTo investigate the efficacy of microimplant-assisted rapid palatal expansion (MARPE) to treat skeletal maxillary discrepancies during the post-pubertal growth spurt stage.Materials and MethodsSixty patients with skeletal maxillary transverse deficiency during the post-pubertal growth spurt stage were randomly divided into MARPE and Hyrax groups. Thirty patients (mean age: 15.1 ± 1.6 years) were treated using the four-point MARPE appliance; 30 patients (mean age, 14.8 ± 1.5 years) were treated using the Hyrax expander. Cone beam computed tomography scans and dental casts were obtained before and after expansion. The data were analyzed using paired t-tests and independent t-tests.ResultsThe success rates of midpalatal suture separation were 100% and 86.7% for MARPE and Hyrax groups, respectively. Palatal expansion and skeletal to dental ratio at the first molar level were greater in the MARPE group (3.82 mm and 61.4%, respectively) than in the Hyrax group (2.20 mm and 32.3%, respectively) (P < .01). Reductions in buccal alveolar bone height and buccal tipping of the first molars were less in the MARPE group than in the Hyrax group (P < .01).ConclusionsMARPE enabled more predictable and greater skeletal expansion, as well as less buccal tipping and alveolar height loss on anchorage teeth. Thus, MARPE is a better alternative for patients with skeletal maxillary deficiency during the post-pubertal growth spurt stage.     

Comparison of traditional RPE with two types of micro-implant assisted RPE: CBCT study

Recently, various types of the Micro-implant Assisted RPE (MARPE) were introduced to obtain greater skeletal expansion and to minimize dental effects. In the present study, we evaluated skeletal and dental effects immediately after the completion of expansion using three different types of expanders— a traditional tooth-anchored maxillary expander (TAME) and two different types of MARPE, bone-anchored maxillary expander (BAME) and tooth-bone-anchored expander (MSE) using CBCT in adolescents. Overall, the MSE group showed much greater skeletal changes than the TAME and BAME groups, especially, at the nasal floor, maxillary base, and palatal suture. About 72–78% of suture opening was at PNS, which indicates slightly more opening anteriorly than posteriorly; however, it was relatively parallel in nature than anticipated. In all three groups, the greatest transverse changes with expansion occurred at the molar crowns and the 2nd greatest changes at the palatal suture opening at ANS. It is suggested that MSE can be a great alternative method in correcting maxillary skeletal transverse deficiency.     

牙周膜牵张成骨正畸牙快速移动的研究

牙周膜牵张成骨正畸牙快速移动与腭中缝快速打开的过程类似.拔牙后,可立即去除移动牙远中的牙槽间隔以减小骨阻力并黏结口内牵张器以快速移动正畸牙.通过此方法,正畸牙可在2～3周内移动到位.牙周膜牵张成骨术节省了支抗并大大缩短了正畸治疗时间.     

Development and Biomechanical Investigation of a New Compound Palatal Arch

BACKGROUND AND AIM: There are many advantages in using a transpalatal arch in orthodontic treatment. In addition to the active movement of individual teeth, such an arch can be used to provide additional anchorage. The aim of this study was to further develop and improve both the clinical and the biomechanical properties of the conventional transpalatal arch. MATERIAL AND METHODS: Currently available compound material components form an established part of orthodontic therapy. The Compound palatal arch broadens the scope of this treatment system. The biomechanical effects of the newly developed Compound palatal arch were verified by comparing them with those of commercially available conventional transpalatal arches. The recently developed Compound palatal arch is made of one compound element: nickel-titanium/stainless steel. The specific dimensions and design of the nickel-titanium element are aimed at exploiting its superelasticity, even during active molar movement. The biomechanical investigation was carried out using six-component measuring sensors to register the forces and moments in the three spatial dimensions (x, y and z) at 37 degrees C. The following appliances were investigated: Goshgarian transpalatal arch, quad-helix appliance, Arndt memory expander, and Compound palatal arch. RESULTS: Transpalatal arches could not be inserted without the arch being under tension. This is particularly important when the arch is being used for anchorage purposes. The Goshgarian arch had to be classified as problematic for the movement of single teeth as the load/deflection rate was high. However, this can be utilized for anchorage purposes. The clinical advantage of a quad-helix appliance is the option for asymmetric tooth movement. CONCLUSIONS: This study showed that the quad-helix was effective for both unilateral and bilateral derotation as well as for transversal tooth movement. However, expansions should be confined to < or = 4 mm, and derotations to < 10 degrees, as forces and moments are otherwise not within the physiologic range. The Arndt memory expander displayed no advantages over either the quad-helix appliance or the Goshgarian transpalatal arch. Nor did it display any superelastic properties. The linear relationship, the relatively high forces and moments, and the lack of clinical adjustability cast doubts on the benefits of this appliance. The newly developed Compound palatal arch showed substantial advantages in molar derotation compared with conventional transpalatal arches. Superelastic properties were achieved through the design and positioning of the nickel-titanium element. Expansion with the Compound palatal arch was comparable with that with conventional transpalatal arches. The clinical advantage is in the fact that this appliance can be reactivated and that dental asymmetries can be treated.     

The study of rapid maxillary expansion in the laboratory animals

Forty rabbits were used to study the rapid maxillary expansion. The widths of the dental arch and the base arch were measured. The histologic changes of the palatal medius suture tissue and periodontal tissue of the anchorage teeth after various degree of rapid maxillary expansion were observed. The result indicated that the width of dental arch and base arch were increased by expansion force. The increasing width of the dental arch almost were caused by the expansion of the medius suture chiefly. The stronger the force, the more the expansion of the palatal medius sutures, but this kind of force might cause the damage of the anchorage tooth periodontal tissue and delay the repairing and remodeling response of the tissue. The medius suture tissue has stronger endurance to the heavy expansion force.     

Evaluation of factors related to the success of miniscrew-assisted rapid palatal expansion

ObjectivesTo evaluate whether the success of miniscrew-assisted rapid palatal expansion (MARPE), performed in patients with advanced bone maturation is related to factors such as midpalatal suture (MPS) maturation, age, sex, or bicortical mini-implant anchorage.Materials and MethodsTwenty-eight cone beam computed tomography (CBCT) scans of adults and post-pubertal adolescents treated by MARPE were included in the sample. CBCT images before (T0) and after expansion (T1) were used to evaluate the skeletal changes and the success or failure of MARPE. Axial images of MPS were extracted from T0 and classified into one of the five maturation stages. The correlation between MARPE success and the factors of age, sex, MPS maturation, and bicortical mini-implant anchorage was investigated.ResultsOnly the age showed a statistically significant negative correlation with MARPE success and all the skeletal measures. There was an 83.3% success rate among individuals aged 15 to 19 years, 81.8% from 20 to 29 years, and 20% from 30 to 37 years. MPS maturation showed a negative correlation with the expansion effect. Subjects with stages B or C of MPS maturation showed a 100% success rate, followed by stage D (62.5%) and stage E (58.3%).ConclusionsAs age increased, there was a decrease in MARPE success and the skeletal effects of maxillary expansion. Sex and bicortical mini-implant anchorage were not shown to be relevant factors. There was no correlation between MPS maturation and MARPE success; however, it was observed that all cases of MARPE failure were classified as stage D or E of MPS maturation.     

Palatal implant anchorage for orthodontic movement: preliminary results with standard Brånemark implants

The aim of this report was to illustrate the preliminary results using standard dental implants as palatal anchorage for orthodontic movement in children and adults. Three teenagers and one adult received six conventional Br?nemark dental implants (6 to 7 mm long) in their palates. The planned therapeutic goals were achieved in every case; however, around two implants, mucosal hyperplasia developed. In one case the hyperplasia was noticed in conjunction with a loosened abutment. The use of conventional dental implants in palatal locations may provide good results, but the efficacy and potential advantages of this treatment must be evaluated in properly designed clinical trials.     

Camouflage treatment of skeletal Class III malocclusion with asymmetry using a bone-borne rapid maxillary expander

This case report presents the successful use of palatal mini-implants for rapid maxillary expansion and mandibular distalization in a skeletal Class III malocclusion. The patient was a 13-year-old girl with the chief complaint of facial asymmetry and a protruded chin. Camouflage orthodontic treatment was chosen, acknowledging the possibility of need for orthognathic surgery after completion of her growth. A bone-borne rapid expander (BBRME) was used to correct the transverse discrepancy and was then used as indirect anchorage for distalization of the lower dentition with Class III elastics. As a result, a Class I occlusion with favorable inclination of the upper teeth was achieved without any adverse effects. The total treatment period was 25 months. Therefore, BBRME can be considered an alternative treatment in skeletal Class III malocclusion.     

锁道式可摘腭弓的制作及其在正畸临床的应用

目的：介绍一种新型的锁道式可摘式腭弓的适应证、制作方法、临床设计以及在临床的应用。方法：应用日本三金公司生产的ST Hook在临床应用设计制作可摘式腭弓，用于牙弓宽度的扩大、加强支抗的设计、个别牙的移动等，并对临床应用21例病例进行了总结和分析。结果：以ST Hook制作的可摘式腭弓具有可调节性、可控性和设计多样性等优点，但应保证制作的准确性以及防止脱落。结论：可摘式腭弓可克服固定腭弓在设计和临床应用中的缺点，在口腔正畸临床矫治中有着较好的应用前景。     

Long-term outcome of skeletal Class II Division 1 malocclusion treated with rapid palatal expansion and Kloehn cervical headgear.

The treatment of a patient with a skeletal Class II Division 1 malocclusion, with excessive overjet, complete overbite, airway obstruction, and severe arch length deficiency in the mandibular dental arch, is presented. The maxilla was narrow compared with the mandible, and the posterior teeth were compensated, with the maxillary teeth inclined buccally and the mandibular teeth inclined lingually. The palatal vault was extremely high. Treatment included rapid palatal expansion to correct the transverse maxillary deficiency and Kloehn cervical headgear to correct the anteroposterior skeletal discrepancy. Long-term stability (12-year follow-up) is reported.     

Orthodontic objectives in orthognathic surgery: state of the art today

In treating jaw discrepancies, camouflage and surgery have different treatment modalities, often involving opposite orthodontic mechanics and different extraction decisions. Pretreatment identification of surgical patients is therefore essential. Esthetics, function, stability, and treatment time have to be considered and patients provided the information they need to be part of the decision-making process. The goal of presurgical orthodontics is to position the teeth, allowing an optimal skeletal correction at surgery. While intra-arch alignment is similar to conventional orthodontics, leveling is not carried out automatically in surgical patients. In open-bite cases, steps within the arches are an indication for segmental surgery. Orthodontic leveling will be limited to the segments, and segments will be leveled with differential intrusion at surgery. In deep-bite/short-face cases, leveling a severe curve of Spee should be done after the occlusion is unlocked by surgery. Anteroposteriorly, dental compensations are removed by ideally positioning the teeth relative to their apical bases. This will make the malocclusion look worse presurgically, but it will unravel the true magnitude of the skeletal problem, thus allowing an optimal correction at surgery. It is important to recognize if a transverse problem is skeletal or dental in nature and if the correction should be done orthodontically, by segmental surgery, or by surgically assisted palatal expansion. No orthodontic expansion should be done presurgically in a patient who will have surgical expansion. Any tooth movement with relapse potential should be avoided presurgically. Postsurgical orthodontics will bring teeth into position and proper intercuspation within a reasonable time period.     

Intrusion of overerupted upper first molar using two orthodontic miniscrews. A case report

Loss of the mandibular first molar often leads to the overeruption of the opposing maxillary first molar, resulting in occlusal interference, loss of periodontal bony support, and inadequate room to restore the mandibular edentulous space. Without orthodontic molar intrusion or segmental surgical impaction, restoring the posterior occlusion often entails the need for significant reduction of maxillary molar crown height, with the potential need for costly iatrogenic root canal therapy and restoration. The literature has cited successful maxillary molar intrusion with minor prosthodontic reduction using palatal orthodontic miniscrews and buccal zygomatic miniplates. In this report, the authors present successful maxillary molar intrusion with two orthodontic miniscrews in a patient with extreme dental anxiety and significant dental erosion due to gastric reflux. Using two orthodontic miniscrews for skeletal anchorage to intrude the maxillary molar simplified the orthodontic treatment by eliminating the need for extensive surgery, headgear, and intraoral multiunit anchorage and preserved indispensable tooth enamel. The clinical results showed significant intrusion through the maxillary sinus cortical floor while maintaining periodontal health, tooth vitality, and root length.     

单侧完全性唇腭裂术后牙弓问横向关系的不调及正畸矫治后变化的探讨

目的 探讨单侧完全性唇腭裂术后患者上下颌牙弓间横向关系以及正畸治疗对上颌牙弓的影响。方法 对84名单侧完全性唇腭裂术后患者的错(牙合)畸形和上下颌颌间关系进行研究;并对36名唇腭裂术后患者进行正畸治疗前后的牙(牙合)模型进行测量分析上颌牙弓宽度的变化。结果 (1)单侧完全性唇腭裂术后60.7％的患者出现牙弓间横向关系的不协调,双尖牙区较易受累。(2)在出现牙弓间横向关系不调的患者中,双侧后牙反(牙合)者为60％。(3)正畸治疗后上颌牙弓的尖牙、第一、第二双尖牙间各自的宽度均有显著增加,第一磨牙间宽度变化不显著。上颌第一、第二双尖牙间各自宽度较尖牙间、第一磨牙间宽度增加显著。结论 单侧完全性唇腭裂术后患者上颌宽度的发育受到明显的限制,牙弓间横向关系不协调的比率较高,以双尖牙区为主;正畸矫治扩弓的重点应在双尖牙区。     

The effects of micro-implant assisted rapid palatal expansion (MARPE) on the nasomaxillary complex—a finite element method (FEM) analysis

Background

Orthodontic palatal expansion appliances have been widely used with satisfactory and, most often, predictable clinical results. Recently, clinicians have successfully utilized micro-implants with palatal expander designs to work as anchors to the palate to achieve more efficient skeletal expansion and to decrease undesired dental effects. The purpose of the study was to use finite element method (FEM) to determine the stress distribution and displacement within the craniofacial complex when simulated conventional and micro-implant-assisted rapid palatal expansion (MARPE) expansion forces are applied to the maxilla. The simulated stress distribution produced within the palate and maxillary buttresses in addition to the displacement and rotation of the maxilla could then be analyzed to determine if micro-implants aid in skeletal expansion.

Methods

A three-dimensional (3D) mesh model of the cranium with associated maxillary sutures was developed using computed tomography (CT) images and Mimics modeling software. To compare transverse expansion stresses in rapid palatal expansion (RPE) and MARPE, expansion forces were distributed to differing points on the maxilla and evaluated with ANSYS simulation software.

Results

The stresses distributed from forces applied to the maxillary teeth are distributed mainly along the trajectories of the three maxillary buttresses. In comparison, the MARPE showed tension and compression directed to the palate, while showing less rotation, and tipping of the maxillary complex. In addition, the conventional hyrax displayed a rotation of the maxilla around the teeth as opposed to the midpalatal suture of the MARPE. This data suggests that the MARPE causes the maxilla to bend laterally, while preventing unwanted rotation of the complex.

Conclusions

In conclusion, the MARPE may be beneficial for hyperdivergent patients, or those that have already experienced closure of the midpalatal suture, who require palatal expansion and would worsen from buccal tipping of the teeth or maxillary complex.     

慢速腭扩展临床研究进展

腭扩展是正畸常用的矫治上颌横向发育不足及上颌牙弓狭窄的固定矫治技术。腭扩展分为快速腭扩展和慢速腭扩展,由于快速腭扩展矫治力较大,存在副作用,而慢速腭扩展可提供更接近生理性的力,严格掌握适应证,可取得较好的临床效果。本文就慢速腭扩展的矫治器类型、骨性和牙性改变以及与快速腭扩展的比较作一综述。     

Combination anchorage technique: an update of current mechanics

Experience and advances in design and technique have greatly enhanced combination orthodontic techniques during the past 5 years. Improvements have made the delivery of treatment more effective and reduced the problems with appliance adjustment and esthetics. Some of these improvements are in the bracket itself, which has been modified for efficiency and esthetics. A modification of treatment technique by the addition of tandem wires, stabilizing arch wires, Dual Flex arch wires, and sectional wires have increased the movement capabilities and anchorage control. A technique of orthodontic mechanics has evolved that is called combination anchorage technique (CAT). The technique is designed to broaden the treatment effectiveness of the orthodontist by providing a combination of orthodontic technical capabilities. Use of the two different bracket slots provides a simple and efficient means to vary (1) anchorage (dynamic or static), (2) movement (tipping or bodily), (3) technique (light wire or straight wire), (4) resistance (one tooth or multiple teeth), and (5) treatment compensation (skeletal or dental).