Damon自锁托槽对安氏I类错（牙合）畸形矫治前后牙弓宽度的变化研究

目的：通过测量牙弓宽度变化探讨Damon自锁托槽矫治安氏I类错(牙合)畸形的作用机制及疗效。方法：21例处于生长发育期的青少年安氏I类患者,采用Damon自锁托槽进行非拔牙矫治,治疗前后进行头影测量和牙弓宽度测量,分析牙弓宽度的变化特征。结果：矫治后患者牙列拥挤均解除,上、下颌牙弓宽度WU4、WU5、WU6、WL3、WL4、WL5、WL6在治疗后均明显增加(P<0.05)。上、下颌前牙治疗后唇倾度增加,UI-NA、LI-MP、LI-NB治疗前后差异均有统计学意义(P<0.05)。结论：Damon自锁托槽对于治疗安氏I类非拔牙矫治有特殊的疗效,可通过增加患者的牙弓宽度解除牙列拥挤,从而达到非拔牙矫治的效果。     

Task Group for Orthodontics Report.

Abstract

The UK Specialist Review Group of the General Dental Council's Education Committee has been charged with taking forward the recommendations in the Chief Dental Officer's report 'UK Specialist Dental Training'. The Specialist Review Group has, in turn, established a number of specialty task groups. This report is from the Task Group for Orthodontics. It was submitted in May 1996.     

An assessment of conventional and self-ligating brackets in Class I maxillary constriction patients

Objective:To evaluate two different treatment systems with regard to incisor position, transverse dimension changes in maxillary arch, changes in maxillary molar inclinations, clinical periodontal parameters, and pain intensity in patients with a Class I malocclusion.Materials and Methods:Seventeen patients (with a mean age of 14.5 years) underwent orthodontic treatment with the Roth prescribed edgewise bracket systems after expanding the maxillary arch with a quad-helix appliance, and 16 patients (with a mean age of 14.8 years) underwent orthodontic treatment with the Damon 3MX bracket system. Each subject''s lateral cephalometric and posteroanterior radiographs and dental casts were obtained at the beginning of the treatment and after debonding. In addition to these, the periodontal index and pain scores were taken.Results:Cephalometric data showed that in both treatment systems, overjet value decreased and maxillary and mandibular incisors proclined. Posteroanterior measurements demonstrated a greater increase in the maxillary molar inclination in the Damon group. Significant increase of maxillary intercanine, interpremolar, and intermolar widths was shown in both systems. Periodontal index and pain score changes between different observation periods were the same.Conclusions:The conventional and Damon systems were found similar with regard to the incisor position, transverse dimension changes in maxillary arch, clinical periodontal parameters, and pain intensity. The only significant difference was that the Damon system inclined the maxillary molars more buccally than the conventional group.     

Damon拔牙与非拔牙矫治前后牙弓宽度变化的研究

目的：比较分析采用Damon矫治技术对牙列拥挤病例进行拔牙与非拔牙矫治的牙弓形态变化。方法：15例中度牙列拥挤病例,使用Damon3矫治器进行非拔牙矫治;15例重度牙列拥挤病例,使用Damon3矫治器进行拔牙矫治。对治疗前后的记存模型进行测量分析,讨论牙弓宽度改变特点。结果：采用Damon矫治技术矫治牙列拥挤的拔牙与非拔牙病例均可取得较好的效果,拔牙组上、下颌尖牙间宽度增大,有统计学意义;非拔牙组上、下颌前磨牙宽度以及上颌第一磨牙间宽度增大,有统计学意义。结论：拔牙组牙弓宽度改变主要与牙齿移动方向有关,非拔牙组牙弓宽度改变与拥挤存在部位以及拥挤程度有关。     

Self‐ligating brackets and treatment efficiency

A number of laboratory studies have shown very low levels of archwire friction for self‐ligating brackets when compared to conventional ligation methods. However, justifiable reservations have been expressed as to the in vivo relevance of these findings. This study was designed to compare treatment efficiency with conventional fully programmed brackets and Damon SL self‐ligating brackets. Thirty consecutively finished cases treated by the author with Damon SL brackets were compared with 30 matched cases treated by the author with conventional brackets. Parallel studies quantified the incidence of technical problems with Damon SL brackets and with conventional ligatures and also the chairside time required for ligation/slide closure and ligature removal/slide opening with these two bracket types. The Damon SL cases required an average of four fewer months and four fewer visits to be treated to an equivalent level of occlusal regularity as measured by the PAR scores.     

Damon技术非拔牙矫治牙列拥挤患者的牙弓形态变化

目的探讨采用Damon技术对牙列拥挤患者进行非拔牙矫治的牙弓形态变化。方法 15例中度牙列拥挤患者,使用DamonⅢ矫治器进行非拔牙矫治。对治疗前后的记存模型进行测量分析,探讨牙弓形态的变化特点。结果矫治后的牙弓长度和宽度均有显著增加,具体的变化特点与牙列拥挤的程度和部位有关。牙弓宽度增加主要发生在上颌第一前磨牙和下颌第二前磨牙区。结论采用Damon技术非拔牙矫治牙列拥挤患者,牙弓形态改变主要是前磨牙区宽度及牙弓长度增加。     

A mechanism of resistance to methotrexate NADPH but not NADH stimulation of methotrexate binding to dihydrofolate reductase

Characteristics of methotrexate (MTX) inhibition of dihydrofolic acid reductase (DHFR) enzyme activity and the effects of NADPH and NADH on enzyme-drug interaction were studied. Two highly sensitive assay procedures were used. The first utilized tritium-labeled MTX to measure direct binding properties of the enzyme and the second utilized tritium-labeled dihydrofolate (H₂PteGlu) and folate (PteGlu) to analyze kinetics of reduction of these substrates. NADPH was found to enhance DHFR binding of MTX (K_d = 2.6 × 1O^?11 M), whereas NADH was found to have no effect (K_d = 3.7 × 10^?9 M). However, NADH proved to be a good substrate for folate reduction compared to NADPH, especially in low salt buffer. The observation that NADH supports the reduction of folate and dihydrofolate but not MTX binding suggests that natural resistance to MTX could exist if NADH replaces NADPH as the main cofactor for DHFR.     

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目的比较自锁矫治器与传统结扎式矫治器用于拔牙矫治病例的矫治效率。方法从2006—2010年青岛大学医学院附属医院口腔正畸科就诊并完成治疗的错畸形病例中选择使用Damon 3MX自锁矫治器(自锁组)与传统结扎式矫治器(结扎组)拔除4颗第一前磨牙病例各15例,分别记录其整平排齐时间、关闭拔牙间隙时间、总体治疗时间及有效复诊次数,并将数据进行统计学分析。结果整平排齐时间:自锁组为(5.8±2.10)个月,结扎组为(4.5±0.71)个月;关闭拔牙间隙时间:自锁组为(8.3±3.65)个月,结扎组为(6.6±2.99)个月;总体治疗时间:自锁组为(20.4±5.04)个月,结扎组为(16.8±2.66)个月;有效复诊次数:自锁组为(19.0±4.83)次,结扎组为(16.4±3.41)次。自锁组的整平排齐时间、关闭拔牙间隙时间、总体治疗时间及有效复诊次数均较结扎组多,但两组间差异均无统计学意义(P>0.05)。结论在拔牙矫治中,Damon 3MX自锁矫治器并未表现出比传统结扎式矫治器更高的矫治效率。     

Damon Q自锁托槽矫治安氏Ⅰ类错畸形牙弓宽度的疗效分析

目的探讨DamonQ自锁托槽矫治安氏Ⅰ类错畸形的疗效。方法 14例处于生长发育期的青少年安氏Ⅰ类患者,采用DamonQ自锁托槽进行非拔牙矫治,治疗前后进行模型分析、头影测量分析、牙弓宽度分析,分析牙、颌骨、牙槽骨尤其是牙弓宽度的变化。结果矫治后患者牙列拥挤均解除,上下颌牙弓宽度均有增加,上下前牙有一定程度的唇倾,均有统计学意义。结论 DamonQ自锁托槽对于治疗安氏I类非拔牙矫治有特殊的疗效,可通过增加患者的牙弓宽度,排齐牙列解除拥挤,从而达到非拔牙矫治的效果。     

高转矩自锁托槽拔牙矫治上颌前突的效果评价

目的 评价和分析DamonQ高转矩自锁托槽矫治器拔牙治疗上颌前突的临床效果。方法 将40例上颌前突需拔除4颗第一前磨牙进行矫治的患者随机分为2组,Damon组上、下颌均使用DamonQ高转矩自锁托槽矫治器,MBT组上、下颌均使用传统MBT直丝弓矫治器,2组均使用滑动法整体内收上前牙。在治疗前（T0）和上前牙内收完成后（T1）测量2组患者的头颅侧位X线片。采用SPSS 11.5软件包比较2组患者的治疗效果。结果 2组患者在T1时上前牙位置均有明显后移,2组间变化量无显著差异,但上唇位置的后移量Damon组为2.31 mm,显著小于MBT组的2.81 mm（P＜0.05）。第一磨牙前移量Damon组为2.33 mm,MBT组为2.36 mm,无显著差异（P＞0.05）。T1时,鼻唇角MBT组和Damon组分别为107.44°和106.33°,而鼻唇角增加量MBT组为9.17°,显著大于Damon组的7.22°（P＜0.05）。上切牙与腭平面的夹角在T1时MBT组和Damon组分别为110.61°和114.11°,而其减少量MBT组为12.06°,显著大于Damon组的7.61°（P＜0.05）。结论 在保证前牙内收效果的基础上,应用DamonQ高转矩托槽拔牙治疗上颌前突患者,在内收前牙阶段与MBT相比,更好地控制了前牙冠唇向转矩,避免了上前牙过度舌倾。