Dental Arch and Cephalometric Changes Following Treatment for Class III Malocclusion by Means of the Function Regulator (FR-3) Appliance

Aim:   

The aim of this retrospective clinical study was to evaluate dental arch, skeletal, dentoalveolar, and soft tissue profile changes following treatment of Class III malocclusion by means of the Function Regulator (FR-3) appliance.     

FR-Ⅲ型矫治器治疗上颌骨发育不足型Ⅲ类错(牙合)的临床分析

目的探讨替牙中期FR-Ⅲ型矫治器矫治上颌骨发育不足型Ⅲ类错(牙合)患者骨骼、牙齿参数变化.方法选择15例安氏Ⅲ类错(牙合)患者,在替牙中期使用FR-Ⅲ型矫治器,治疗前、结束后均拍摄头颅侧位片,并对其进行测量分析.结果通过上切牙唇倾、下切牙舌倾、下颌向后向下旋转,前牙可建立正常覆盖覆(牙合)关系.结论替牙中晚期,FR-Ⅲ型矫治器是治疗上颌骨发育不足型Ⅲ类错(牙合)的一种有效方法.     

Lip Morphology Changes Following Orthognathic Surgery for Class III Malocclusion

Objectives:To test the hypothesis that there is no difference in the morphology of the lips and to determine the degree of improvement in the smile after orthognathic surgery for Class III malocclusion.Materials and Methods:The sample subjects included 30 adult female patients with dento-skeletal Class III malocclusion and 28 adult female volunteers with normal occlusion. Frontal facial photographs were taken before and after treatment, and 35 landmarks were placed on each tracing made from the frontal facial photograph. Thereafter, the landmarks were digitized into an x and y coordinate system with the subnasal point as the origin. The pretreatment rest and smile conditions were compared with the posttreatment conditions, respectively, using paired t-tests. In addition, two sample t-tests were used to test for differences between groups.Results:Both the upper and lower lips in the smiles of the Class III pretreatment group were positioned downward, and the upward movement of the upper lip and commissure points were smaller compared with the control group. When smiling, the horizontal direction of the mouth corners was statistically significantly different between the pretreatment and posttreatment conditions, whereas these were wider in the posttreatment than in the pretreatment conditions. These characteristics of the Class III smile improved after orthognathic treatment, but the differences with the control group remained unchanged immediately after treatment.Conclusion:The hypothesis is rejected. The soft tissue morphology of patients with dento-skeletal Class III malocclusion shows a significant improvement after orthognathic surgery.     

Cephalometric Changes in the Treatment of Class III Using the Fränkel Appliance*

AIM: In this retrospective clinical study, we aimed to evaluate skeletal changes following treatment of Class III malocclusion by means of the Function Regulator (FR-3) appliance. MATERIAL AND METHODS: The group of patients we treated with the FR-3 exclusively consisted of 56 subjects (20 boys and 36 girls). Fifteen subjects (7 boys and 8 girls) of approximately the same age and presenting almost identical characteristics of a Class III malocclusion of skeletal etiology served as a control group (between the ages of 7 and 15 years). Lateral cephalograms were compared using the occipital reference structures as proposed by Fr?nkel. RESULTS: Cephalometric analysis showed that maxillary landmarks (point A, nasospinale), and the upper incisor (root included) did move significantly farther forward in the treated group than in the control group (p < 0.01). We also found that the gonial angle decreased by 7.17 degrees in the FR-3 group, as opposed to 2.07 degrees in the untreated group (p < 0.001). No significant differences were noted in mandibular-length growth (Ar-Pog, Ar-Go, Go-Pog). CONCLUSION: According to these study results, FR-3 treatment has an obvious effect on maxillary development, and affects the shape and, to a certain degree, the position of the mandible.     

改良Herbst矫治器矫治青春期Ⅱ类1分类错患者头影测量分析

目的分析改良Herbst矫治器对青春期安氏Ⅱ类1分类错患者的治疗效果。方法应用改良Herbst矫治器对20例生长发育高峰期Ⅱ类1分类错患者进行治疗,平均治疗时间8.5个月,治疗前后拍摄X线头颅定位侧位片,比较治疗前后颌骨、牙齿及软组织变化,应用配对t检验对测量结果进行分析。结果 SNA角、U6-PP距的治疗前后差异无统计学意义（P〉0.05）;SNB角、L1-MP、Co-Go距、Go-Gn距、Co-Gn距、Sn-A’-UL、LL-B’-Pos的增大有统计学意义（P〈0.05）;ANB角、Wits值、OJ值、U1-SN角、UL-E线距、LL-E线距、Co-S值的减小有统计学意义（P〈0.05）。结论应用改良Herbst矫治器对生长发育高峰期Ⅱ类1分类错患者进行功能矫形治疗可以取得较好的治疗效果。     

Cephalometric Characteristics of Korean Children with Class III Malocclusion in the Deciduous Dentition

Objective:To compare the cephalometric characteristics of children with Class III malocclusion to those of children with normal occlusion during the deciduous dentition phase.Materials and Methods:Cephalometric measurements of 27 children (mean age: 5.03 years) diagnosed with Class III malocclusion were compared with 32 children (mean age: 4.85 years) diagnosed with normal occlusion in the following four categories: sagittal skeletal analysis, vertical skeletal analysis, dentoalveolar analysis, and soft tissue analysis.Results:Significant differences were seen in all categories except vertical skeletal analysis. Sagittal skeletal measurements included ANB (Class III group: −0.91 ± 1.60; normal group: 5.28 ± 1.29), facial convexity (Class III group: 0.47 ± 4.32; normal group: 13.65 ± 3.44), Wits appraisal (Class III group: −5.54 ± 2.36; normal group: −0.84 ± 1.91), and A to N-perpendicular (Class III group: −2.94 ± 3.05; normal group: 0.78 ± 2.53). Dentoalveolar measurements included U1 to NA (Class III group: 11.98 ± 5.25; normal group: 8.12 ± 5.43), IMPA (Class III group: 81.34 ± 7.40; normal group: 86.57 ± 5.67), and interincisal angle (Class III group: 152.65 ± 8.82; normal group: 145.03 ± 7.34). Soft tissue measurements included soft tissue convexity (Class III group: 2.47 ± 4.20; normal group: 12.71 ± 3.95), nasofacial angle (Class III group: 22.68 ± 4.22; normal group: 26.24 ± 3.84), and upper lip to esthetic plane (Class III group: −0.65 ± 2.74; normal group: 3.07 ± 1.90).Conclusions: There are significant differences between the craniofacial patterns of normal children and those of children with Class III malocclusion that can be identified with cephalometric analysis as early as the deciduous dentition phase.     

Fr(a)nkel矫治器对安氏Ⅱ类错(牙合)患者髁突和下颌位置的影响

目的了解Frankel矫治器治疗安氏Ⅱ类错(牙合)过程中,髁突和下颌位置的变化情况.方法选择经Frankel矫治器治疗成功的安氏Ⅱ类错(牙合)患者30例,男女各15例,对其治疗前后的头颅侧位定位片进行X线头影测量重叠分析.结果①前颅底结构重叠显示治疗后患者的髁突点、下颌角点和颏前点发生明显的下移,同时男性患者颏前点发生明显的前移.②下颌结构重叠显示治疗后患者的髁突点发生明显的上移和后移(移位比约为2:1),下颌角点相对颏部发生后移.结论Frankel矫治器能刺激安氏Ⅱ类错(牙合)患者髁突的生长,有利于下颌水平向的改建.     

片断弓技术纠正成人安氏二类错(牙合)伴深覆(牙合)时牙颌位置的变化

目的:通过研究矫正前后牙颌位置的变化,证实片断弓技术纠正成人安氏二类错伴深覆的有效性。方法:选择16例(平均年龄25.8岁)安氏Ⅱ类伴Ⅲ度深覆病例,利用片断弓压低辅弓技术打开咬至正常约2mm。计算T1期和T2期各测量指标的平均值和标准差。采用t检验检测各测量指标之间是否具有组间显著性差异。结果:深覆纠正至2mm,平均覆减少2.9mm,P<0.01具有显著性差异。上下前牙分别被压低1.4mm,1.5mm(P<0.001)且处于相对稳定的近远中位置(L1~NPg=-0.3mm,NS)。下颌后牙未见显著性升高。平面顺时针倾斜增加2°(P<0.01)。下颌平面未见明显的改变。结论:片断压低辅弓技术很有效地实现了压低前牙,而后牙没有出现显著性的升高,深覆纠正后基本维持原有的下颌平面倾斜角度。     

Development of a New Fixed Functional Appliance for Treatment of Skeletal Class II Malocclusion First Report

Developed under interdisciplinary cooperation, the Functional Mandibular Advancer (FMA) is a new, rigid and fixed appliance for sagittal correction of the intermaxillary jaw relationship in adolescents and young adults. The appliance is non-dependent on patient compliance and is aimed at providing an alternative to the Herbst and MARA appliances. A number of designs, all based on the mechanical principle of the inclined plane combined with guide pins and allowing reactivation, were developed. The version of the appliance providing the best technical advantages was developed to the stage of practical application in patients.     

Ⅲ类患者与Ⅰ类患者牙槽骨及牙弓宽度的比较

目的：本文的主要目的是将Ⅲ类错畸形患者的牙弓、牙槽骨宽度与与Ⅰ类患者的值进行比较。方法：本研究共收集47例成人Ⅲ类患者,50例成人Ⅰ类患者。在术前研究模上测量牙弓与牙槽骨宽度,并对两组测量值进行独立样本T检验的统计比较。结果：Ⅲ类患者上颌除上尖牙间宽度外,其余测量值均小于Ⅰ类患者。而下颌所有测量值,Ⅲ类患的测量值均大于Ⅰ类患者。结论：Ⅲ类患者,上颌牙弓及牙槽骨宽度窄于I类患者;下颌牙弓及牙槽骨宽于Ⅰ类患者。     

头帽-肌激动器一下唇挡矫治器治疗安氏Ⅱ错（牙合）的临床研究

目的：研究头帽一肌激动器一下唇挡矫治器治疗生长发育期安氏Ⅱ类1分类错（牙合）对骨骼、牙齿和软组织的影响。方法：选择20例安氏Ⅱ类1分类患者,随机分两组分别采用头帽一肌激动器一下唇挡矫治器和头帽一肌激动器～进行治疗,常规拍摄治疗前后的头颅侧位片进行分析,对结果进行T检验。结果：Pg／OLP显著增加,Si--LiPg明显减少。结论：头帽一肌激动器一下唇挡矫治器组能更好的刺激下颌的发育,明显改善患者侧貌。     

Skeletal and Dental Effects of Maxillary Protraction in Patients with Angle Class III Malocclusion A Meta-Analysis

The aim of this study was a quantitative review of the published results concerning the treatment effects of maxillary protraction in patients with Angle Class III using the meta-analysis method. 85 articles published between 1966 and 1998 were reviewed under strict, pre-defined criteria. Of these, 12 studies presenting results of cephalometric measurements were selected for further analysis. The results of different cephalometric measurements were reviewed with Dstat 1.10 software in order to calculate a standardized treatment effect variable. The homogeneity of the variances of the different effect variables as well as a composite effect were calculated. For the latter, each individual effect variable was weighted by the reciprocal of its variance, with predefined study characteristics being used for categorical model calculations. Our results showed a significant composite effect of the therapy on the skeletal components (SNA: 1.4 degrees, composite effect = 1.11; SNB: -1.3 degrees, composite effect = -0.94; ANB: 2.6 degrees, composite effect = 1.73; lower anterior face height: 1.6 mm, composite effect = 0.85) as well as on the dental components of the face (inclination of upper incisors: 1.6 degrees, composite effect = 0.37; inclination of lower incisors: -3.7 degrees, composite effect = -0.87). However, several of the individual effect variables demonstrated a significant lack of homogeneity. Study characteristics which might possibly account for this variability were the patients' ages at the start of treatment and the combination of maxillary protraction with rapid maxillary expansion. In summary, maxillary protraction was shown to have a significant treatment effect. The meta-analysis method proved to be a valuable tool in judging the current status of a given clinical therapeutic concept.     

Size Discrepancy of Apical Bases and Treatment Success in Angle Class III Malocclusion

The aim of this retrospective clinical study was to measure the apical bases and determine their size relationship in Class III malocclusion cases before and after orthodontic treatment, in order to evaluate their significance for the treatment success. Maxillary and mandibular apical bases were measured on study models of 104 Class III cases treated by conventional orthodontics, using a specifically constructed conveyance apparatus, and related to each other as an index. Treatment success was quantitatively assessed as the percentage change of PAR scores obtained from the pretreatment and posttreatment study models. Statistically significant relationships were disclosed between the measurements of the apical bases and several other evaluated parameters. The results obtained indicate a high prognostic value of the size relationship of the apical bases for the treatment success of Class III malocclusion.     

肌激动器和FRⅡ型功能矫治器治疗安氏Ⅱ类1分类错（牙合）的对比研究

目的:比较肌激动器和FrnkelⅡ(FRⅡ)型功能矫治器治疗安氏Ⅱ类1分类错（牙合）的效果.方法:选择处于生长发育高峰期或高峰前期的患儿34例,其中12例用肌激动器矫治,22例用FRⅡ型矫治器矫治.所有患儿均为凸面型,上颌前突和(或)下颌后缩;ANB角≥5°;磨牙及尖牙为远中关系.对比每个患儿矫治前后的模型和头侧位片并作统计学分析.结果:矫治结束后所有患儿磨牙和尖牙均达到或接近中性关系,ANB角减小至正常范围.使用FRⅡ型矫治器组的患儿牙弓宽度比肌激动器组明显增加,而两组的基骨弓宽度无显著性差异.FRⅡ型矫治器使上切牙内收更显著,而肌激动器更能有效地控制下切牙的倾斜度.结论:两种功能矫治器都能有效地改善上下颌骨及牙弓的Ⅱ类关系.     

功能矫治器矫治安氏Ⅱ类Ⅰ分类错(牙合)的软组织侧貌变化

目的用5项软组织美学指标,评价功能矫治器矫治安氏类Ⅰ分类错牙合的软组织变化。方法对21例安氏类Ⅰ分类错牙合患者用功能矫治器(FR-2)矫治前后的X线头影测量片进行分析,对比治疗前后软组织5项美学指标的变化。结果通过早期的功能矫形治疗,患者大多数美学指标接近正常值范围,但也有部分指标改善不明显。结论功能矫治能使大多数患者软组织侧貌得到明显改善,但存在个体差异,部分病例仍需要二期治疗。     

功能矫治器矫治安氏Ⅱ类Ⅰ分类错He的软组织侧貌变化

目的 用5项软组织美学指标，评价功能矫治器矫治安氏类Ⅰ分类错殆的软组织变化。方法 对21例安氏类Ⅰ分类错He患者用功能矫治器(FR-2)矫治前后的X线头影测量片进行分析，对比治疗前后软组织5项美学指标的变化。结果 通过早期的功能矫形治疗，患者大多数美学指标接近正常值范围，但也有部分指标改善不明显。结论 功能矫治能使大多数患者软组织侧貌得到明显改善，但存在个体差异，部分病例仍需要二期治疗。