Dental occlusion and postural control in adults

We studied the influence of a dental occlusion perturbation on postural control. The tests were performed in three dental occlusion conditions: (Rest Position: no dental contact, Maximal Intercuspal Occlusion: maximal dental contact, and Thwarted Laterality Occlusion: simulation of a dental malocclusion) and four postural conditions: static (stable platform) and dynamic (unstable platform), with eyes open and eyes closed. A decay of postural control was noted between the Rest Position and Thwarted Laterality Occlusion conditions with regard to average speed and power indexes in dynamic conditions and with eyes closed. However, the head position and stabilization were not different from those in the other experimental conditions, which means that the same functional goal was reached with an increase in the total energetic cost. This work shows that dental occlusion differently affects postural control, depending on the static or dynamic conditions. Indeed, dental occlusion impaired postural control only in dynamic postural conditions and in absence of visual cues. The sensory information linked to the dental occlusion comes into effect only during difficult postural tasks and its importance grows as the other sensory cues become scarce.     

功能性矫治器治疗替牙期反的头影测量前后变化

目的:观察用FRⅢ型功能矫治器矫治替牙期反的临床效果。方法:在正畸临床中选择替牙期的安氏Ⅲ类错畸形患者15名,采用FRⅢ型功能矫治器进行Ⅰ期矫治,并进行X线头影测量,比较矫治前后的硬组织变化。结果:所有病例在该期治疗结束时SNA、U1-SN、U1-NA、ANB、Y轴角增大;SNB、L1-NB、L1-MP减小。结论:FRⅢ型功能矫治器是治疗替牙期前牙反的一种理想矫治器。     

Ⅲ类颌间牵引治疗无生长潜力唇腭裂术后患者前牙反（牙合）的机制研究

目的：比较单侧完全性唇腭裂术后患者前牙反（牙合）解除前后颅面结构变化,探讨Ⅲ类颌间牵引治疗单侧完全性唇腭裂术后患者前牙反（牙合）的机制。方法：选择单侧完全性唇腭裂术后前牙反（牙合）患者20名,其中男15名,女5名,平均年龄（14.36±1.06）岁。所有患者在牙列排齐和整平的基础上行Ⅲ类颌间牵引,测量前牙反（牙合）解除前后头颅定位侧位片上反映颅面结构的各项指标,用配对t检验比较治疗前后的变化。结果：前牙反（牙合）解除后,SNB、L1-MP、OP-SN、NLA、ULP减小,ANB、MP-SN、NA-PA、U1-SN、U6-FH、L1-MP、L6-MP、ULL、LLL、LLP、UL-EP增大,差异有统计学意义。前牙反（牙合）解除前后SNA、U1-FH、LL-EP、ISD差异无统计学意义。结论：对于恒牙期唇腭裂术后反（牙合）的患者,Ⅲ类颌间牵引在纠正上下颌牙齿及牙槽关系不调的同时,能掩饰颌骨矢状向Ⅲ类关系,使软组织侧貌得到显著改善。     

前方牵引矫治替牙期骨性Ⅲ类错秴的临床研究

目的探讨前方牵引对于替牙期骨性Ⅲ类错秴的应用及临床疗效。方法选择替牙期骨性Ⅲ类错秴患者16例,年龄范围6～10岁,应用前方牵引器矫治前牙反,对矫治X线头影测量结果进行分析。结果秴对于替牙期骨性Ⅲ类错秴的前方牵引治疗能够促进上颌骨生长,下颌骨轻度向下向后旋转,软组织面型改善,SNA显著增大,平均增大1.95°,ANB角度增大3.0°。结论替牙期前方牵引治疗骨性Ⅲ类错秴有效,软组织侧貌明显改善,有利于Ⅲ类骨骼畸形的调整。     

单侧后牙反患者髁状突及下颌升支对称性的螺旋CT研究

目的:探讨单侧后牙反成年患者髁状突及下颌升支的对称性。方法:对22例单侧后牙反患者进行螺旋CT扫描、多层面重建和相关参数测量,并进行统计分析。结果:双侧髁突内、外突点的距离,髁突内倾角及下颌角点的距离有显著差异,但髁突左右径、髁状突最大横截面积、下颌支高度及下颌支冠状位最大面积的差异无统计学意义。结论:单侧后牙反患者左右侧髁状突及下颌支的位置不对称,但髁突及下颌升支大小无显著差异。     

Three-dimensional assessment of palatal area changes after posterior crossbite correction with tooth-borne and tooth bone–borne rapid maxillary expansion: A randomized controlled trial with 5-year follow-up

ObjectivesTo assess and compare the three-dimensional treatment changes in palatal surface area and volume using either tooth-borne (TB) or tooth bone–borne (TBB) rapid maxillary expanders and to evaluate the long-term effects of the two devices and the incidence of the relapse between the groups.Materials and MethodsA total of 52 consecutive patients who met the eligibility criteria were recruited and allocated to either the TB group, mean age 9.3 years (standard deviation [SD], 1.3), or the TBB group, mean age 9.5 years (SD, 1.2). Study casts were taken before, directly after, 1 year after, and 5 years after expansion. Study casts were digitized, superimposed, and evaluated. Participants were randomly allocated in blocks of different sizes using the concealed allocation principle in a 1:1 ratio.ResultsChanges in palatal volume, palatal surface area, and palatal projection area within and between the groups up to 5 years after expansion followed the same pattern and did not show any statistically significant differences between the groups. Relapse was seen in 15% of the patients. It seemed that open-bite and a Class III growth pattern could be assumed as prognosis-deteriorating factors in regard to stability of the treatment.ConclusionsThere were no significant differences between the TB and TBB groups in palatal volume, palatal shell area, or palatal projection area directly after expansion or at 1 year and 5 years after expansion, which implies that the two devices gave rise to the same immediate and long-term outcomes.     

Surgical treatment of maxillary transverse deficiency: retrospective study of 14 patients

Introduction  

The diversity of the proposed techniques in the treatment of maxillary transverse deficiency in adults reflects the conflicting opinions about the primary area of resistance to maxillary expansion in the craniofacial skeleton. In order to evaluate the efficiency of the surgical expansion in which no osteotomies of the pterygomaxillary junction were made, we have carried out a retrospective study with 14 patients with maxillary transverse deficiency, who were treated from 2003 to 2006.     

Early risk factors for posterior crossbite and anterior open bite in the primary dentition

Objective:To investigate risk factors specific to posterior crossbite and anterior open bite at the age of 3 years.Materials and Methods:The study included 422 children of the French EDEN mother-child cohort. The main outcomes were the presence of posterior crossbite and anterior open bite assessed by dentists at 3 years. Social characteristics (collected during pregnancy), neonatal characteristics (collected at birth), duration of breast-feeding (collected prospectively), sucking habits at 3 years, and open lips (as a proxy for mouth breathing) were studied and two logistic regressions conducted.Results: Preterm birth appears to be a risk factor specific for posterior crossbite (OR: 3.13; 95% CI: 1.13–8.68), whereas small for gestational age seems to be associated with a lower risk of posterior crossbite (OR: 0.32; 95% CI: 0.12–0.87). Ongoing pacifier or thumb sucking at 3 years is a risk factor for both posterior crossbite and anterior open bite.Conclusions: Children born preterm seem to be more at risk for posterior crossbite than those born at term. Different mechanisms may be involved in posterior crossbite and anterior open bite.     

长箭头卡的临床应用

Admas氏卡环(改良式箭头卡)是活动式矫正器常用的固位装置.临床实践证明对于缺乏倒凹的乳磨牙,其固位力常显不足.长箭头卡是Admas氏卡环的改进,它能有效地克服此种缺陷.     

正畸矫治第二磨牙正锁

上颌第二磨牙正锁(牙合)时常发生,正畸临床矫治有一定的难度.依据错(牙合)的不同情况,作者提出4种临床矫治方法:一是上下颌牙齿交互牵引;二是利用上下颌的正畸弓丝移动上下牙齿向颊、舌方向;三是拔除锁(牙合)牙,让第三磨牙自动近移替代第二磨牙;四是利用种植钉作支抗,用皮链牵引其达到正常牙位;评估了4 种矫治方法的优、缺点.在讨论中叙述了矫治的临床应用、如何选择矫治方法以及在矫治过程中的注意事项.