不同厚度异体皮制备的微粒皮混合自体微粒皮移植对创面愈合的影响

目的　观察不同厚度异体皮制备的微粒皮混合自体微粒皮移植于大鼠背部全层皮肤缺损后对创面愈合的影响。　方法　制作大鼠全层皮肤缺损创面模型。以移植面积扩张比为 5∶1的自体微粒皮为对照组 ( 10只 ) ,两种不同厚度异体皮制备的微粒皮与同样扩张比的自体微粒皮混合移植为实验组 ,其中实验 1组异体微粒皮厚度为 0 .3mm(10只 ) ,实验 2组 0 .6mm(6只 )。比较移植后 2、3、4周 3组大鼠创面愈合率、收缩率及组织学差异。　结果　创面愈合率 :移植后 2周实验 1组大鼠( 94 .5 8± 3.99) %和实验 2组 ( 95 .2 8± 1.93) %均高于对照组 ( 88.2 8± 6 .85 ) % (P <0.0 5 ),移植后 3周实验 2组 ( 94 .5 5± 3.4 7) %高于实验 1组 ( 89.5 1± 4 70 ) %及对照组 ( 88.5 1± 5 .5 9) % (P <0.0 5),移植后 4周 3组比较 ,差异无显著性意义 (P >0 0 5 )。创面收缩率 :实验 1组大鼠与对照组比较 ,差异无显著性意义 (P >0.0 5),实验 2组各时相点均低于实验 1组及对照组 (P <0.0 5)。组织学检查 :移植后 2周实验组大鼠有明显的淋巴细胞灶性浸润 ,移植后 4周 3组之间比较 ,差异无显著性意义 ( P>0.0 5 )。结论　适量的异体微粒皮混合自体微粒皮移植 ,可以促进创面愈合 ;混合移植等量异体微粒皮时增加其真皮厚度 ,能够减     

透明质酸钠预防面颈部外伤及手术后瘢痕50例

目的:观察外源性透明质酸钠抑制创口瘢痕形成的临床效果.方法:外伤及手术后的患者100例,随机分成两组,实验组用1.7%的透明质酸钠创口局部定期注射,对照组作空白对照.观察创口术后的缝线反应,计算创口愈合后不同时期同等长度瘢痕的面积.结果:术后1周两组缝线反应有显著性差异(P＜0.05).两组瘢痕面积在术后1、3、6个月时比较有显著性差异(P＜0.05).结论:创口局部注射外源性透明质酸钠能有效抑制创面瘢痕形成.     

人工合成成骨生长肽促进兔胫骨骨折愈合的实验研究

目的观察人工合成的成骨生长肽(sOGP)经静脉应用对兔胫骨骨折愈合的影响。方法52只新西兰大白兔制成胫骨中段截骨、髓内钉固定骨折模型后,随机分为两组。实验组从术后第1d开始每天注射sOGP0.5μg·kg-1至取材前1d,对照组注射同样剂量的生理盐水。分别于术后第1、2、3、4、6周每组宰杀3～5只,测定血清ALP、BGP;同时取材测定骨折端骨密度、摄X线片后,再行组织学检查和形态分析,观察骨痂的大小及其组成成分的变化;其中术后6周的标本还进行了生物力学测定。结果实验组血清ALP、BGP水平高于对照组。X线片显示两组骨折均愈合,第3、4周实验组外骨痂平均面积比对照组大,3周时为265.44mm2、209.95mm2,4周时为233.10mm2、209.21mm2。第3、4、6周的骨密度实验组均大于对照组,其中第4周的骨密度经F检验两组的差异具有显著性(P<0.05)。组织学形态分析显示第2、3、4周的外骨痂平均面积实验组比对照组大;所有实验组外骨痂中小梁骨占骨痂总面积的百分比均高于对照组,其中第2、4周经F检验两组的差异具有显著性(P<0.05)。第6周骨折端平均最大破坏载荷及最大位移实验组比对照组高,但差异没有显著性(P>0.05)。结论全身应用sOGP对不稳定固定的兔胫骨横断骨折的愈合具有一定的促进作用。     

植入型复方丹参缓释剂对骨折愈合影响的实验研究

目的:观察丹参缓释剂植入骨折局部对骨折愈合的影响.方法:42只新西兰健康白兔随机分为两组,均于右前肢桡骨中段制成3mm骨缺损的骨折模型,同时实验组放置丹参缓释剂60mg,对照组放置等量赋形剂.分别于术后第2、4、5、6周取右桡骨行X线片及组织学检查;第2、4、6周行电镜及骨密度检查;第5、6周进行生物力学测试.结果:X线片显示实验组较对照组骨折愈合提前.组织学观察实验组纤维性骨痂、软骨性骨痂、骨小梁之间过渡加快,毛细血管增生明显.电镜检查实验组示骨折修复细胞形态学变化均有利于修复骨折.术后第2、4、6周时骨密度值实验组均较对照组高,其中第4周时两者差异具有显著性(P＜0.05).术后第5、6周实验组抗折力均较对照组高(P＜0.05).结论:在骨折局部使用丹参缓释剂对骨折愈合具有一定的促进作用.     

眶周软组织扩张术对眶距增宽矫正后骨愈合的影响

目的　建立兔眶距增宽矫正手术的动物模型 ,探讨使用眶周软组织扩张技术对眶内移后骨愈合的影响。方法　 4～ 6个月龄新西兰兔 1 6只 ,随机分为两组 ,一组为实验组 ,眶周软组织扩张后 ,行颅内外联合径路眶周截骨眶内移 ;另一组为对照组 ,眶周软组织不扩张 ,直接眶周截骨眶内移。 1 6只兔均在眶内移术后 1 2周处死 ,取下眶间骨胳进行内眶距测量 ,X线摄片和组织学检查。结果　术后 1 2周 ,实验组平均内眶距为 (5 .7± 0 .4 )mm ,对照组平均内眶距为 (6 .8± 0 .7)mm ,两组有显著性差异 (P <0 .0 1 )。X线结果可见 ,术后 1 2周实验组较对照组骨密度增高 ,截骨间隙缩小。组织学检查证实 ,对照组眶间新生骨组织较多。结论　使用眶周软组织扩张技术 ,可有效地防止眶内移后眶距增宽的复发 ,证明眶周软组织不足 ,是眶距增宽矫正术后复发的原因之一     

口腔综合防治措施对固定矫治患者菌斑指数的影响

目的:初步探讨口腔综合防治措施对患者菌斑指数的影响。方法:将固定矫治后牙釉质脱矿需接受护牙素治疗的20例青少年患者,随机原则分实验组和对照组各10例患者。实验组用Toot h Mousse护牙素全口局部涂抹并按事先制订的口腔综合防治计划,采用语言、示范、文字相结合的教育方式,对患者进行口腔卫生宣教。对照组仅用Toot h Mousse护牙素局部涂抹治疗,不做口腔卫生宣教。比较两组基线、基线后1周,基线后4周菌斑指数的变化。结果:实验组基线后1周、基线后4周菌斑指数较基线减少并好于对照组,组间比较有统计学差异,但实验组基线后4周菌斑指数较基线后1周有所反弹。结论:口腔综合防治措施有助于控制固定矫治后牙釉质脱矿患者的菌斑指数,有利于牙釉质的再矿化。     

电动牙刷对正畸治疗中防龋效果的影响

目的观察口腔固定正畸治疗中患者使用电动牙刷2年控制菌斑和预防龋病的效果。方法选择年龄在12～14岁的戴用固定矫治器的正畸患者60例,实验组使用电动牙刷,对照组使用保健牙刷。采用菌斑染色法记录实验前和经过2年实验后,两组患者菌斑牙面数、菌斑指数和患龋情况,并进行统计分析。结果实验组菌斑清除率为67.11%,对照组为41.58%,菌斑指数和新患龋在两组间差异有统计学意义（P〈0.01）。结论使用电动牙刷比普通牙刷更能帮助固定正畸患者有效消除牙面菌斑,预防龋齿,在固定正畸中预防龋病值得推广应用。     

眶周软组织扩张术对眶距增宽矫正后骨愈合的影响

目的建立兔眶距增宽矫正手术的动物模型,探讨使用眶周软组织扩张技术对眶内移后骨愈合的影响.方法 4～6个月龄新西兰兔16只,随机分为两组,一组为实验组,眶周软组织扩张后,行颅内外联合径路眶周截骨眶内移;另一组为对照组,眶周软组织不扩张,直接眶周截骨眶内移.16只兔均在眶内移术后12周处死,取下眶间骨胳进行内眶距测量,X线摄片和组织学检查.结果术后12周,实验组平均内眶距为(5.7±0.4)mm,对照组平均内眶距为(6.8±0.7)mm,两组有显著性差异(P<0.01).X线结果可见,术后12周实验组较对照组骨密度增高,截骨间隙缩小.组织学检查证实,对照组眶间新生骨组织较多.结论使用眶周软组织扩张技术,可有效地防止眶内移后眶距增宽的复发,证明眶周软组织不足,是眶距增宽矫正术后复发的原因之一.     

磷酸三钙结合富血小板血浆修复股骨头坏死的研究

目的　研究磷酸三钙 (tricalcium phosphate,TCP)和富血小板血浆 (platelet- rich plasma,PRP)混合物(TCP/PRP)修复兔股骨头无菌性坏死的作用机制。　方法　成年新西兰大白兔 4 8只 ,采用液氮冷冻兔股骨头制成股骨头坏死模型 ,再随机分成 2组 ,每组 2 4只 ,实验组植入 TCP/PRP,对照组植入 TCP。分别于术后 2、4、8和 12周取材 ,行X线片、组织学检查、电镜观察和计算机图像处理。　结果　 X线片示术后 2周 ,两组股骨头密度无明显差异 ;4周 ,两组骨密度均降低 ,对照组下降更明显 ;8和 12周时骨密度均升高 ,实验组升高更明显。组织学检查 :术后 2周光镜显示 ,实验组肉芽增生多于对照组 ;4周时股骨头变平 ,凹陷缺损 ,实验组少于对照组 ;8和 12周股骨头纤维增生 ,骨小梁增粗 ,实验组修复较对照组多。电镜 :术后 2周实验组成骨细胞内线粒体和粗面内质网较多 ;4周实验组成骨细胞和胶原纤维明显比对照组多 ,细胞器比对照组成熟 ;8周时实验组的成骨细胞向骨细胞转化较多 ,雏形板层骨较多。计算机图像处理 :术后 4、8和 12周实验组骨小梁体积分别为 36 .6 5 %± 7.2 2 %、38.2 9%± 4 .2 8%和 39.2 4 %± 3.4 2 % ,明显多于对照组(P<0 .0 5 )。　结论　 TCP/PRP不仅为成骨细胞爬行提供支架 ,并能促进新骨形成和股     

线粒体在脓毒症淋巴细胞凋亡中的作用

目的 研究线粒体在脓毒症淋巴细胞凋亡中的作用机制.方法 用雌性、6～8周、C57BL/6小鼠建立盲肠结扎穿孔(CLP)的脓毒症动物模型.将实验动物随机分为两组:对照组、CLP组.分离脾淋巴细胞,采用Annexin V-FITC/PI标记,流式细胞仪检测脾淋巴细胞的凋亡变化;罗丹明123标记,流式细胞仪检测线粒体膜电位的变化;分离脾淋巴细胞线粒体和胞质组分,Western blot法检测细胞色素C在线粒体、胞质中的含量变化.结果 CLP组脾淋巴细胞的凋亡率为(17.3±2.2)%,较对照组的(3.5±0.5)%明显增高(P＜0.05);CLP组线粒体膜电位无降低的细胞占(76.2±1.6)%,较对照组的(99.6±0.4)%明显减少(P＜0.05);CLP组脾淋巴细胞线粒体和胞质内的细胞色素C含量与对照组相比,差异均有统计学意义(P＜0.05).结论 在脓毒症时,线粒体及其信号传导通路在淋巴细胞凋亡中发挥了重要作用.     

Study of potassium phytate effects on decreasing urinary calcium in rats

BACKGROUND: Phytate as sodium salt has been used at high doses to treat stone-former patients with idiopathic hypercalciuria. The experimental and clinical hypocalciuric effects of dietary fiber have also been assigned to the presence of phytate as calcium-magnesium salt (phytin). As a consequence of the additional interest in phytate due to its capacity as crystallization inhibitor, now a study of the effects of potassium phytate on urinary calcium excretion is presented and compared with the effects caused by other phytate salts. METHODS: To study the effect of calcium-magnesium phytate, 36 Wistar rats (6 groups) were fed with a purified diet in which phytate was practically absent (4068.02 Reference Diet). Three groups were fed with increasing calcium amounts and with the same amount of phytin, each one corresponding to one control group. To study the effects of magnesium-potassium, sodium and potassium phytate salts, 48 Wistar rats (8 groups) were fed with UAR-A04 diet (a standard diet which contains 0.8% of phytin). Two control groups fed with low and high calcium amounts and 6 treated groups were formed. The effect of the dose of potassium phytate on urinary calcium was carried out using 2 additional groups of 6 Wistar rats each one fed with UAR-A04 diet and increasing amounts of potassium phytate. RESULTS: No significant changes in urinary calcium were observed when phytin (calcium-magnesium phytate) was supplied. The urinary calcium was clearly reduced by the three phytate salts assayed (magnesium-potassium, sodium, potassium), but the most significant decrease was noticed when the potassium phytate salt was administered. Phytate administration, independently of the salt or dose used, did not significantly affect the urinary oxalate. CONCLUSION: It can be clearly deduced that the effects of phytate on the urinary parameters, mainly calcium, fundamentally depend on the type of salt used. Thus, the most remarkable effects on urinary calcium reduction were caused by the potassium salt. Obviously, these findings must be confirmed in human studies.     

Low-frequency electromagnetic field exposure accelerates chondrocytic phenotype expression on chitosan substrate

To find whether low-frequency pulsed electromagnetic fields help repair larger cartilage defects with the assistance of tissue-engineered scaffolds, we tested their effect on the behavior of chondrocyte cells cultured on chitosan films. Primary porcine chondrocytes growing on chitosan films were exposed to low-frequency pulsed electromagnetic fields (frequency=75 Hz; impulse width=1.3 ms; strength=1.8-3 mT) 2 hours a day for 3 weeks. The cells that were not exposed to low-frequency pulsed electromagnetic fields served as controls. For 3 weeks, cell proliferation, viability, and expressions of type II collagen and glycosaminoglycan were measured weekly. Cell morphology and histological stains of glycosaminoglycan and type II collagen were performed at the end of the test. The cell proliferation and viability of the low-frequency pulsed electromagnetic fields group and the control were similar each week. By the end of the third week, cells in the low-frequency pulsed electromagnetic fields group deposited 28% more glycosaminoglycan than the control cells. The amounts of type II collagen deposited in the low-frequency pulsed electromagnetic fields group were 24% and 27% higher than those of the control group by week 2 and 3, respectively. Histological and immunohistochemical analyses confirmed the releases of glycosaminoglycan and type II collagen. Cells from both groups grew in aggregates and possessed a spherical shape after 3 weeks. These results suggest that low-frequency pulsed electromagnetic fields can enhance extracellular matrix production on chitosan substrate. Combining tissue engineering and low-frequency pulsed electromagnetic fields could further accelerate cartilage repair.     

左甲状腺素钠治疗重症肺结核伴正常甲状腺病态综合征临床分析

目的 探讨对重症肺结核伴正常甲状腺病态综合征（euthyroid sick syndrome,ESS）的患者应用小剂量左甲状腺素钠治疗的有效性.方法 将120例重症肺结核伴ESS住院患者按性别、年龄、病程、疾病严重程度随机分为治疗组和对照组.治疗组在常规抗结核及控制感染、营养对症支持治疗的基础上加服小剂量左甲状腺素钠（12.5μg/d）,对照组按常规治疗,治疗时间均为2周.比较两组甲状腺功能、临床症状改善、白蛋白升高、痰涂片抗酸杆菌减少、影像学改善情况及病死率.结果 治疗2周后,两组患者发热、咳嗽、盗汗等症状有不同程度好转,其中治疗组中显效者19例（31.7%）,对照组中显效者8例（13.3%）,两组比较差异有统计学意义（χ2=5.73,P＜0.05）.治疗组痰菌转阴15例（25.0%）,对照组4例（6.7%）,两组比较差异有统计学意义（χ2=7.50,P＜0.01）.治疗组患者治疗后血清白蛋白升高至（34.2±0.4）g/L,明显高于对照组的（29.1±0.6）g/L,经比较两组的差异具有统计学意义（t=2.42,P＜0.05）.两组患者的T3、FT3在治疗后均明显上升,但治疗组升高尤为显著,两组治疗前后差值比较差异有统计学意义（t值分别为59.42和50.66,P值均＜0.01）.治疗组与对照组均未见空洞闭合,但有部分患者的结核病灶出现吸收好转,其中治疗组治疗有效56例（93.3%）,对照组治疗有效46例（76.7%）,两组比较差异有统计学意义（χ2=6.54,P＜0.05）.治疗组未出现死亡病例,对照组病死率为3.3%（2/60）.结论 对重症肺结核伴ESS的患者在常规治疗的前提下,再辅以小剂量左甲状腺素钠治疗安全有效,低T3的改善是整个病情好转的重要指标.     

两种漂白方法对牙本质与树脂粘结强度影响的实验研究

目的：比较牙本质经两种漂白方法漂白后,在不同时间粘结树脂其抗剪强度变化。方法：25颗恒前磨牙随机分为5组。A组为对照组：人工唾液内3周后制备牙本质粘结面,粘结树脂;B组：牙齿外漂白每天6h,共3周后制备牙本质粘结面,粘结树脂;C组：牙齿外漂白3周,人工唾液内储存2周后制备牙本质粘结面,粘结树脂;D组：牙齿内漂白3周后制备牙本质粘结面,粘结树脂;E组：牙齿内漂白3周,人工唾液内储存2周后制备牙本质粘结面,粘结树脂。电子万能实验机测试剪切粘结强度。结果：①抗剪强度测试结果：A组（18.61±3.56）MPa,B组（10.74±3.03）MPa,C组（17.21±3.15）MPa,D组（12.10±2.64）MPa,E组（16.78±2.84）MPa;②统计学分析：A-E组试件的剪切强度值单因素方差分析（one-wayANOVA）表明5组样本均数之间存在统计学差异（P〈0.05）。各组均数两两比较（Student-Newman-Keuls,SNK-q法）显示A与B组,A与D组,B与C组,D与E组的剪切强度值差别有统计学意义（P〈0.05）,而A与C组,A与E组,B与D组,C与E组的剪切强度值之间无统计学差异（P〉0.05）。结论：①两种漂白方法对牙本质与树脂粘结强度的影响无明显差别;②牙齿漂白后即刻粘结树脂,两种漂白方法均会降低牙本质与树脂的粘结强度;③牙齿漂白后延迟2周再粘结树脂,两种漂白方法均能够恢复牙本质与树脂的粘结强度接近未漂白组的水平。     

A Drug Holiday Reduces the Frequency and Severity of Medication-Related Osteonecrosis of the Jaw in a Minipig Model

Treatment of medication-related osteonecrosis of the jaw (MRONJ) is challenging and no clear consensus has been achieved. This study investigated preventive measures recommended for tooth extractions under antiresorptive (AR) treatment and the role of discontinuation of AR therapy to avoid the onset of MRONJ in a minipig model. Thirty-six Göttingen minipigs were divided into four groups. Group 1 (negative control): tooth extractions but no zoledronate (ZOL). Group 2 (positive control): weekly ZOL infusions for 12 weeks followed by tooth extractions without wound management followed by 8 weeks of ZOL treatment. Group 3: weekly ZOL infusions for 12 weeks followed by tooth extractions; surgical wound management (resection of sharp bone edges, mucoperiosteal coverage); and continuation of ZOL infusions for 8 weeks plus antibiotic treatment. Group 4: 12 weeks of ZOL infusions followed by a drug holiday for 6 weeks. Tooth extractions with preventive wound management followed by antibiotic treatment for 8 weeks but no ZOL infusions. Jawbones were subjected to macroscopic, radiological (CT and micro-CT) and histopathological investigations. No clinical cases of MRONJ were observed in the negative group, in the positive control all animals developed MRONJ. Group 3 developed MRONJ in 83% of cases. With a drug holiday, 40% developed MRONJ in areas of tooth extraction. This is the first large animal model that reduces the occurrence of MRONJ following tooth extraction by the implementation of a drug holiday combined with antibiotic prophylaxis and smoothening of sharp bony edges. © 2020 The Authors. Journal of Bone and Mineral Research published by American Society for Bone and Mineral Research..     

再矿化疗法对新型漂白术后釉质显微硬度影响及牙齿增白的效果

目的探讨低浓度漂白剂配合使用含氟牙膏与否,对漂白后的牙釉质显微硬度和增白效果的影响。方法将20颗无缺损的离体磨牙随机分成A、B、C3组,A、B两组各8颗,C组4颗作为对照组,A、B两组的颊面采用6％过氧化脲（carbamideperoxide,CP）漂白,舌面采用30％CP漂白,每天漂白30min,持续2周,在此期间对B组牙用含氟牙膏刷牙,每天15min,随后将所有牙齿浸泡于37℃的人工唾液中,测定漂白前、后的牙齿的亮度值及釉质显微硬度,并进行统计学分析。结果两种漂白剂使用2周后对牙釉质的脱矿作用不明显（P〉0．05）,含氟牙膏刷牙可增加漂白后牙釉质显微硬度（P〈0．05）,但对漂白后的亮度无影响。结论漂白间歇期使用含氟牙膏刷牙,使过CP漂白术更为安全,且不影响漂白的效果。     

Enalapril and low protein reverse chronic puromycin aminonucleoside nephropathy

The effects of dietary protein and converting enzyme inhibition (CEI) on chronic puromycin aminonucleoside nephropathy (PAN) were studied. PAN was induced with seven SQ injections of puromycin aminonucleoside 20 mg/kg over 10 weeks in male Sprague-Dawley rats. The rats were divided into a 22.5% protein diet group (Gr 1), a 6% protein diet group (Gr 2), and an enalapril-treated group on 22.5% protein diet (Gr 3). Group 4 animals served as age-matched controls. Both diets were isocaloric and had the same phosphorus content. Rats from groups 1, 2, and 4 were sacrificed at 12, 18 and 24 weeks. Five rats of group 3 were sacrificed at 12 weeks, and the others were divided in subgroups 3A (diet changed to 6% protein) and 3B (no changes); half of each subgroup was sacrificed at 18 and 24 weeks, respectively. Group 2 had significantly less proteinuria than group 1 at all times. Group 3 had the same proteinuria as group 1 until 12 weeks and then began to decrease. In group 3A proteinuria decreased to group 2 levels, while in group 3B the decrease was slower but still prominent. Early lesions of focal and segmental glomerular sclerosis/hyalinosis (FSH) were present in groups 1, 2, 3 at 12 weeks (16 +/- 1.2%, 15 +/- 1.3%, 7 +/- 1.3%, respectively, versus 1.3 +/- 0.4% in controls), but by 18 weeks a reversal in FSH was seen in groups 2 and 3A/B (3 +/- 1.6%, 2 +/- 0.4%, and 3 +/- 0.9%, respectively, vs. 14 +/- 1.5% in group 1).(ABSTRACT TRUNCATED AT 250 WORDS)     

过氧化脲漂白剂的临床效果评价

目的：研究不同增稠载体的10％过氧化脲（carbamide peroxide,CV）漂白剂的临床漂白效果。方法：以卡波姆（carbopol）、聚乙烯吡咯烷酮（PVP）为增稠载体,配制1O％CP漂白凝胶,以Opalescencc（OP）10％CP漂白凝胶作为对照。选择18名轻度四环素牙患者,漂白前1周常规洁牙,清除牙齿表面的任何外源性着色,浮石粉浆抛光。将患者随机分为3组：1组用以Carbopol为增稠载体的10％CP漂白;2组用以PVP为增稠载体的10％CP漂白;3组用OP10％CP漂白凝胶漂白,疗程为2周。分别在漂白1、2周,漂白后1、3、6个月通过DIC和GIANT重复测色,计算色差（△E）,漂白前后自身对照,并对牙齿、牙龈的敏感度进行评价。结果：漂白1周和2周牙齿明度和色差变化明显,组内差异非常显著（P〈0．01）,各组间无明显差异（P〉0．05）;漂白后1、3、6个月,牙齿明度和色差逐渐下降,组内差异非常显著（P〈0．01）,组问无明显变化（P〉0．05）。3组之间的牙齿敏感度和牙龈敏感度均无显著差别（P〉0．05）。漂白后1周以内,所有患者的敏感症状均缓解。结论：以Carbopol或PVP为增稠载体的10％CP漂白剂和OP10％CP漂白凝胶短期（2周）临床漂白效果显著,漂白后随着时间的延长,牙齿颜色有不同程度的反弹,它们与OP10％CP漂白凝胶的漂白效果、反弹趋势以及对牙齿、牙龈敏感度的影响没有显著差异。     

Color differences of canines and incisors in a comparative long-term clinical trial of three bleaching systems

This study was a long-term clinical trial of home and in-office LED and laser bleaching systems comparing for the first time interdental color differences (differences between the central labial surfaces of the canine and the central incisor). A total of 90 patients were divided into three groups of 30 each. One group received day guard vital bleaching, and the other two groups received one bleaching session for 20 min accelerated by a diode laser for 30 s per tooth or a blue LED for 3 min per tooth, and both groups received additionally day guard for 7 days. A total of four color measurements were carried out during the study period of 3 months and 3 weeks. The group treated with the LED tended to show the highest degree of equalization of lightness, chroma and hue. A significantly stronger overall increase in lightness was observed for canines after treatment when compared with incisors resulting in more homogeneous lightness values.     

舌侧正畸治疗中牙釉质脱矿的临床观察及预防措施

目的：了解舌侧正畸治疗后牙釉质脱矿情况及氟保护漆预防和减少牙釉质脱矿的疗效,探讨预防脱矿的简便易行方法。方法：将20例舌侧正畸患者随机分为两组进行观察。实验组10例,在舌侧正畸托槽周围牙面涂布氟保护漆;对照组10例,患者仅进行日常的口腔卫生护理。结果：舌侧正畸治疗患者牙釉质脱矿发生率为17．35％,上颌侧切牙脱矿率最高,好发部位部位为托槽龈方和牙齿邻面;实验组牙釉质脱矿程度较对照组明显降低,具有统计学意义。结论：舌侧正畸治疗中使用氟保护漆是预防和降低牙釉质脱矿的有效途径。