Nd:YAG口腔激光联合康复新液治疗青少年正畸后慢性牙龈炎的疗效及对口腔健康状况的影响

目的探讨Nd:YAG口腔激光联合康复新液治疗青少年正畸后慢性牙龈炎的疗效及对口腔健康状况的影响。方法将90例正畸后慢性牙龈炎青少年按随机数字表法分为研究组、对照A组、对照B组,每组30例。3组均予以牙龈清洁术,于此基础上,对照A组予以Nd:YAG口腔激光治疗,对照B组予以康复新液治疗,研究组予以Nd:YAG口腔激光联合康复新液治疗。比较3组疗效、治疗前后牙龈疼痛程度、牙龈肿胀程度、口腔健康状况指标(探诊深度、龈沟出血指数、菌斑指数、牙龈指数)、龈沟液炎症因子指标(前列腺素E2、可溶性黏附分子-1、白细胞介素-1β)水平。结果研究组治疗总有效率显著高于对照A组、对照B组(P<0.05)。研究组治疗后牙龈疼痛程度及肿胀程度均显著低于对照A组、对照B组(P<0.05),探诊深度、龈沟出血指数、菌斑指数、牙龈指数水平显著低于对照A组、对照B组(P<0.05),龈沟液前列腺素E2、可溶性黏附分子-1、白细胞介素-1β水平显著低于对照A组、对照B组(P<0.05)。结论Nd:YAG口腔激光联合康复新液治疗青少年正畸后慢性牙龈炎疗效显著,能显著减轻牙龈炎症反应,降低牙龈肿胀、疼痛程度,改善口腔健康状况。     

Damon Q自锁托槽在数字化牙颌模型上的模拟定位研究

目的 探讨数字化托槽模拟定位的准确性。方法 对15例数字化牙颌模型上的牙齿（每例28颗）进行托槽模拟定位,定位方法分别采用托槽高度定位法和含牙根信息托槽定位法。采用OrthoRx软件形成矫治后的最终状态;采用美国正畸目标评分系统（ABO-OGS）评估矫治结果,测量指标包括牙齿排齐、后牙边缘嵴高度及牙根平行度3项。结果 1）虚拟矫治后两种托槽定位方法的边缘嵴高度扣分均小于治疗前（P<0.05）,但两种方法虚拟矫治后边缘嵴高度扣分没有统计学差异（P>0.05）。2）含牙根信息托槽定位法虚拟矫治后牙根平行度扣分小于托槽高度定位法,但两种方法虚拟矫治前后牙根平行度未发生明显改善。3）在牙齿排齐及3项总扣分方面,两种托槽定位方法在虚拟矫治前后扣分的差异有统计学意义,矫治后扣分均小于治疗前,含牙根信息托槽定位法矫治后的扣分小于托槽高度定位法（P<0.05）。结论 在重建的包含牙根的三维数字化模型上,采用OrthoRx软件,通过托槽高度定位法及含牙根信息定位法进行托槽定位,模拟矫治均有效果;通过含牙根信息托槽定位法的模拟矫治效果更好。     

第三磨牙与错牙合畸形的相关性研究

第三磨牙先天缺失和阻生是现代人肌肉、颌骨和牙齿不平衡退化的重要体现,出现在口腔各类错牙合畸形中。第三磨牙的存在和缺失是否会影响错牙合畸形的形成和矫治后的复发,正畸治疗是否会影响第三磨牙的萌出,临床上正畸医生如何对第三磨牙进行合理取舍,这些问题为正畸医生所关注。     

口腔正畸中三维有限元法的发展

正畸过程就是作用力的体现过程,所以正畸的研究离不开生物力学分析。随着计算机技术的普及和发展,三维有限元分析这种力学分析方法日趋成熟。因其模型具有良好的几何相似性,以及可以进行复杂几何形态的分析被广泛的应用于生物力学领域。本文主要讲述了三维有限元法的定义、运算步骤和在口腔正畸领域的牙体、牙周、种植体等多个方 面的应用和进展以及今后三维有限元分析法在正畸生物力学中的发展方向。     

The wisdom behind third molar extractions

The literature pertaining to the extraction of third molars is extensive. There is a large individual variation and a multitude of practitioners’ beliefs and biases relating to the extraction of especially asymptomatic and pathology free third molars. With the current emphasis in dentistry being placed on clinicians to make evidence‐based decisions, the routine removal of third molars has been re‐assessed and questioned. The purpose of this paper was to evaluate past and present knowledge of third molar extractions and relate it to logical considerations relevant to science and the evidence‐based decision‐making process. This paper endeavours to encourage and stimulate clinicians to re‐evaluate their views on third molar extractions based on suggested guidelines and current evidence.     

牙周病致前牙间隙患者的无托槽隐形矫治初探

目的 应用无托槽隐形矫治技术治疗因牙周病导致前牙间隙的患者,评价矫治过程中患者牙周状况的变化,以期为临床提供参考.方法 选取7例因轻、中度牙周炎导致前牙间隙的患者,矫治前患者前牙间隙为3.0～4.5 nnn,平均3.4 mm.应用无托槽隐形矫治技术进行正畸治疗,关闭前牙散在间隙.观察矫治前和矫治1、3、6个月患者牙龈探诊出血(bleeding on probing,BOP)阳性位点百分比和平均探诊深度;评价矫治前和矫治1、6个月上前牙釉质牙骨质界至牙槽嵴顶的距离(CEJ-ABC距)的变化.结果 疗程4～6个月,矫治后所有患者牙间隙完全关闭,矫治3、6个月BOP阳性位点百分比分别为1.2%,1.8%,与矫治前(0%)相比,差异均无统计学意义(P>0.05);矫治1、3、6个月患者平均探诊深度分别为(1.49±0.13)、(1.58±0.11)、(1.57±0.15)mm,与矫治前[(1.50±0.12)mm]相比,差异均无统计学意义(P>0.05).矫治1、6个月上前牙间CEJ-ABC距与矫治前相比,差异均无统计学意义(P>0.05).结论 无托槽隐形矫治技术可用于轻、中度牙周病致前牙间隙的患者,短期观察未见牙周组织损伤.     

Osteoclast differentiation and recruitment during early stages of experimental tooth movement in rats

Osteoclasts are derived from macrophage-lineage precursors. ED1 is an antibody that can recognize this lineage of cells. Matrix metalloproteinase 9 (MMP9) is essential for the migration of osteoclasts and their precursors during osteoclastogenesis. The aim of this research was to investigate differentiation and recruitment of osteoclasts during the early phase of experimental tooth movement in rats. The upper three molars of Wistar rats at one side were moved mesially, using Ni–Ti coil springs of 10 cN, for 6, 12, 24, 36, 48, 72, 96, and 120 h. The contralateral sides served as controls. Immunohistochemical staining using ED1 and MMP9 antibodies was performed. ED1⁺ and MMP9⁺ mononuclear and multinuclear cells were counted and statistically analysed. After force application, the number of ED1⁺/MMP9⁺ multinuclear cells first increased in the bone marrow. At compressed areas, the number of ED1⁺ mononuclear cells decreased; this was followed by an increase in the number of ED1^+/MMP9⁺ mononuclear and multinuclear cells. At tension areas, the number of ED1⁺/MMP9⁺ multinuclear cells decreased while the number of ED1⁺ mononuclear cells remained stable. It was concluded that force application induces osteoclast differentiation within the bone marrow. These osteoclasts probably migrate subsequently into the compressed PDL. Pre-existing osteoclasts disappear at the tension areas while the number of mononuclear macrophage-lineage cells remains stable.     

正畸治疗中磨牙的拔除和保留（四十四）——骨性Ⅲ类错[牙合]畸形拔除下颌磨牙矫治后追踪观察

目的：观察恒牙期骨性Ⅲ类错[牙合]拔除下颌磨牙矫治及矫治后4年牙、[牙合]、面形态的变化。方法：恒牙期骨性Ⅲ类错[牙合]病例22例（男6例、女16例）。年龄12．1～16．9岁,平均14．2±1．6岁。均拔除下颌第一或第二磨牙后采用直丝弓矫治器进行掩饰性治疗,并在矫治结束后追踪观察2．8—7．5年,平均4．3±2．2年。治疗前（TD）、治疗后（t1）及追踪期末（T2）头颅侧位片以Pancherz头影测量方法进行分析。结果：治疗结束后上下颌前牙覆盖增加5．37mm（P〈0．001）,i—i／Olp减少4．67mm（P〈0．001）,ii／Olp—Pg／Olp减少3．15mm（P〈0．01）;LL／Olp减少2．18mm（P〈0．01）,UL／Olp—LL／OIp减少2．47mm／1（P〈0．001）。在追踪期内前牙覆盖减少1．73mm（P〈0．001）,ii／Olp增加2．85mm（P〈O．01）;A／Olp增加1．07mm（P〈0．05）,Pg／Olp增加1．97mm（P〈0．05）。将追踪期末的数据与治疗期间比较,虽有复发但与治疗前比较仍有显著改善。结论：恒牙期骨性Ⅲ类错胎畸形患者在拔除下颌第一或第二磨牙矫治后下颌切牙的内收使前牙反覆盖得以纠正。在追踪期内随着内收切牙的复发及下颌矢状向生长,前牙覆盖显著减小,与治疗前相比有显著增加。在软组织方面,下唇凸点在治疗期间的后退导致上下唇凸点间的距离显著减小,从而患者的软组织侧貌得以改善,在追踪期末患者仍然维持良好的软组织侧貌。在治疗期及追踪期内患者前下面高增加并在观察期末出现下颌平面角的增大。     

The interdental gingiva,a visible guide for placement of mini‐implants

Authors – Chun YS, Lee SK, Wikesjö UME, Lim WH Objectives – To determine whether the tip of the interdental gingiva can serve as a visible guide for placement of mini‐implants. Setting and Sample population – Computer tomography (CT) images from 15 males and 15 females (mean age 27 years, range: 23–35 years) were used to evaluate the distance from the tip of the interdental gingiva to the alveolar crest from the central incisor to the 1st molar. The distance from a reference point to the tip of interdental gingiva was recorded from study models using a caliper. The distance between the reference point and the alveolar crest was recorded using CT and added to the model recordings thus providing the distance from the tip of interdental gingiva to the alveolar crest for the various interdental sites. Two‐way anova and Student–Newman–Keuls test for multiple comparisons were used for the statistical analysis. Results – There was no significant difference in the distance from the tip of interdental gingiva to the alveolar crest between maxilla and mandible. The distance between the tip of interdental gingiva and the alveolar crest at the central/lateral incisors was the shortest compared with that of other sites. There was also a statistically significant difference between the male and female groups except for the maxillary 2nd premolar/1st molar interradicular site. Conclusion – The tip of interdental gingiva appears a reasonable visual guide for the placement of mini‐implants for orthodontic anchorage.