刷牙方法和时间对菌斑清除效果的影响

目的检查刷牙方法和时间对菌斑清除效果的影响。方法3种刷牙方法刷牙3min后检查菌斑附着牙面数，与刷牙前菌斑附着牙面数进行比较；检查并比较巴斯刷牙法刷牙3、4、5、6min后菌斑附着牙面数。结果刷牙3min后巴斯刷牙法使菌斑牙面数减少53．95％，旋转刷牙法使菌斑牙面数减少49．57％，生理刷牙法使菌斑牙面数减少44．48％，三者比较差异有统计学意义（P〈0．01）；巴斯刷牙法刷牙5min后菌斑百分率为15．88％，与刷牙4min以下比较差异有统计学意义（P〈0．01），与刷牙6min比较差异无统计学意义（P〉0．05）。结论巴斯刷牙法清除菌斑的效果优于旋转刷牙法和生理刷牙法；用巴斯刷牙法刷牙3min能达到清除菌斑的目的，但需刷牙5min以上才能达到较好的菌斑控制效果。     

乳牙菌斑附着部位的分析

目的观察分析全口乳牙的菌斑附着状况。方法应用菌斑染色片对120名5岁幼儿进行乳牙菌斑检查。结果120名儿童PI均值为1.69±0.01，男、女间无显著性差异；上后牙颊面PI最高；乳磨牙菌斑总量高于乳前牙；上颌牙唇颊侧菌斑附着多于腭侧、下颌牙舌侧多于唇颊侧。结论上述菌斑附着多的牙及牙面需强化刷牙。     

Hellman IIA期的菌斑附着

作者以Ｐｌａｑｕｅ Ｉｎｄｅｘ（ＰＩ）检查和剖析了１０５名（男５４名，女５１名）ＨｅｌｌｍａｎⅡＡ期幼儿的菌斑附着，结果显示男女间无显著差异。统计表明全口ＰＩ中，下颌多于上颌，乳磨牙多于乳前牙；上颌之ＰＩ以颊面最多，下颌则以舌面为多；ＰＩ在牙面间有显著差异；同名牙相比，下颌之ＰＩ多于上颌。分析结果可供指导幼儿刷牙时作了参考。     

正畸矫治器对牙面细菌组成变化的影响

目的:探讨戴用固定矫治器对牙面细菌组成的影响。方法:选择50例正畸患者按照不同口腔卫生措施要求分为两组。10例未经正畸治疗者作为对照组。分别于戴矫治器前,戴入后2、4、8周采集左下第一磨牙及右下第二双尖牙的菌斑,测定菌斑的细菌组成。结果:下颌第一磨牙带环戴入前后不同时期、不同刷牙频率和时间,检出的牙面菌斑细菌组成无明显差异。下颌第二双尖牙粘托槽后,牙面菌斑细菌组成发生显著变化,杆菌比例升高,球菌比例下降,而口腔卫生措施的不同也对菌斑细菌的组成有明显影响。结论:戴用托槽后,下颌第二双尖牙远中区菌斑细菌杆菌比例增高,易成为诱发牙龋坏和牙龈炎的潜在因素。但通过加强刷牙漱口的频率和时间,有助于减少牙龋坏和牙龈炎的发生。     

HellmanⅡA期的菌斑附着

作者以ＰｌａｑｕｅＩｎｄｅｘ（ＰＩ）检查和剖析了１０５名（男５４名，女５１名）ＨｅｌｌｍａｎⅡＡ期幼儿的菌斑附着，结果显示男女间无显著差异。统计表明全口ＰＩ中，下领多于上领，乳磨牙多于乳前牙；上领之ＰＩ以颊面最多，下颌则以舌面为多；Ｐｌ在牙面间有显著差异；同名牙相比，下颌之ＰＩ多于上颌。分析结果可供指导幼儿刷牙时作一参考。     

刷牙后菌斑再生长的临床评价

目的　比较观察刷牙后残留菌斑的再生长或牙面重新形成新菌斑的动态变化。方法　 6 0位志愿者刷牙前和刷牙后 0、4、8、12和 2 4h ,以Rustogi等改良Navy菌斑指数记录 6个指数牙的菌斑分布情况。结果　刷牙后 4h ,所有区的菌斑指数与刷牙后 0h比较均有显著差异 (P <0 .0 1)。刷牙后 2 4h所有区的菌斑指数与刷牙前己差异不显著 ,即菌斑指数己恢复到刷牙前水平 ,仅光滑区菌斑指数与刷牙前仍有显著差异 (P <0 .0 1)。结论　现有的习惯刷牙方法刷牙 4h后牙面菌斑与刷牙后即刻比较己有显著差异 ,龈缘区、邻间隙区是菌斑快速再生长或重新形成的区域。     

伴有附着丧失的乳磨牙无菌斑区宽度研究

对拔除的已有附着丧失的乳磨牙牙根无菌斑区面积进行测量,结果表明:无菌斑区面积在乳磨牙的近中面宽于颊侧和舌侧之和,其差异有显著性(P<0.001).无菌斑区在下颌乳磨牙面积大于上颌乳磨牙,第二乳磨牙范围大于第一乳磨牙,平均宽度1.75±0.49mm,其     

儿童使用声波震动牙刷清除牙菌斑的效果观察

目的:观察儿童使用声波震动牙刷清洁牙及控制菌斑的效果。方法:选择年龄6～7岁的儿童50例,实验组使用声波震动牙刷,对照组使用儿童保健牙刷。采用菌斑染色法记录刷牙前后的菌斑牙面数及菌斑指数(PLI),采用SPSS10.0统计软件包对相关组间数据进行t检验与χ2检验。结果:实验组菌斑清除率为70.22%,对照组为39.08%,声波震动牙刷去除舌面、近中颊面菌斑的能力是手动刷牙的2倍。刷牙前后菌斑指数和菌斑清除率在2组间有高度显著性差异(P<0.001)。结论:声波震动牙刷能有效帮助儿童清除牙面菌斑,是儿童口腔护理的有效工具。     

新型压低下颌磨牙矫治器的临床应用

目的 评估新型压低下颌磨牙矫治器压低下颌磨牙的疗效及应用价值.方法 选择7例需要压低下颌磨牙治疗的前牙开患者,治疗前、后通过临床检查、牙颌模型分析及采用Winceph7.0数字化X线片分析软件测量头颅侧位片,评价临床压入效果,使用SPSS 17.0统计软件包对数据进行分析.结果 7例患者经过平均4个月的治疗,均取得比较明显的治疗效果.治疗前、后头影测量分析表明:下颌第一磨牙的平均压入量为(1.92±0.44)mm,矫治前、后相对于基准平面(MP平面)的垂直距离差异有统计学意义(P<0.05).上颌第一磨牙平均压入量为(0.36±0.25)mm,矫治前、后相对于基准平面(PP平面)的垂直距离差异没有统计学意义(P>0.05).X片显示被压低的下颌磨牙未出现明显的牙根吸收.结论 新型下颌磨牙压低矫治器用于压入下颌磨牙治疗前牙开畸形效果明显,压入治疗未引起明显的牙周及牙根损害.     

滑动杆与口外弓联合治疗安氏ⅡS错(牙合)畸形的X线头影测量分析

目的 研究口外弓结合滑动杆推上颌第一磨牙远移矫治安氏Ⅱ类亚类错(牙合)畸形磨牙远移的变化。方法 10例患者进行推上颌第一磨牙远移治疗前、后的X线头影对比研究。平均治疗101天,其测量值作统计学t检验。结果 磨牙均被纠正为安氏Ⅰ类关系。上颌磨牙平均远移3.78±2.02mm(P<0.01),同时伴有上颌磨牙的远中倾斜,平均3.2°±1.4°;下颌磨牙平均近移0.99±0.63mm(P<0.01)。给论 纠正磨牙关系为Ⅰ类关系有赖于一定比率的下颌磨牙近移。SNA角、SNB角、Y轴和PP/MP角的相对稳定,对颌骨无影响。     

A clinical assessment of the effectiveness of mouthwashes in comparison to toothbrushing in children

The study compared the efficacy of unsupervised tooth-brushing done once a day before breakfast (phase 1), with twice daily mouthrinsing with the three different commercially available mouthwashes containing 0.2% sodium fluoride (phase 2), a combination of 0.03% triclosan and 0.05% sodium fluoride (phase 3), and 0.2% chlorhexidine (phase 4) in 20 children aged 13-14 year, in reducing dental plaque formation. The results showed that there was a statistically significant difference in plaque reduction between phases 1 & 2; 1 & 3; 2 & 4 and 3 & 4. The mandibular arch harboured more plaque than the maxillary arch in phase 1 (p<0.05). Irrespective of the mouthwash used, the lingual/palatal surfaces had less plaque than the facial surfaces (p<0.05). The mean cumulative plaque scores of the mandibular lingual surfaces was more in comparison to the maxillary palatal surfaces in phases 1, 2 and 3 (p<0.05). It was therefore, concluded that 0.2% chlorhexidine was comparable to tooth brushing done once a day, before breakfast.     

正常(牙合)青少年替牙期至恒牙初期切牙和磨牙转矩度的纵向观察

目的：研究正常胎青少年从替牙期到恒牙初期切牙和第一恒磨牙转矩度的生长变化，为正畸诊断、治疗方案设计提供依据。方法：对北京大学口腔医学院·口腔医院颅面生长发育中心收集的20名正常胎青少年样本（男性6名，女性14名）替牙期和恒牙初期的牙颌模型进行分析：替牙期：第一恒磨牙及4颗恒切牙萌出至胎平面，研究对象平均（9.5±0.9）岁；恒牙初期：除第三磨牙外其他恒牙均萌出至眙平面，研究对象平均（13．7±1．3）岁。使用BiagginiRayset系统测量切牙和第一恒磨牙的转矩度，分析替牙过程中牙冠倾斜度的变化。结果：替牙期与恒牙初期相比，男、女切牙和磨牙的转矩度差异均无统计学意义（P〉0．05）。替牙期至恒牙初期，上颌中切牙转矩度由14。减小为10.9°（P〈0．001）；下颌中切牙转矩度由1．8°增加为5.2°（P〈0.01）；上颌侧切牙转距度的变化无统计学意义（P〉0．05）；下颌侧切牙转矩度由1．2°增加为3．0°（P〈0．05）。上颌第一恒磨牙转矩度由-6．6°减小为-10．3°（P〈0．001）。下颌第一恒磨牙转矩度由一38．6°增加为-33.2°（P〈0，001）。结论：从替牙期到恒牙初期，上颌第一恒磨牙逐渐舌向直立，下颌第一恒磨牙逐渐颊向直立。     

Comparison of normal permanent and primary dentition sagittal tooth-crown inclinations of Japanese females

The purpose of this study was to clarify the characteristics of permanent and primary tooth-crown inclinations. Landmark points from cephalograms and dental casts of two groups; 23 women (mean 20.3 +/- 3.3 years) and 11 girls (mean 5.2 +/- 0.1 years) were digitized, and the coordinates were integrated and transformed to a standardized plane. The 3-dimensional crown inclinations were projected on the sagittal plane, and the angles between the tooth vectors and the FH plane were calculated. An independent-group t-test was used to test for group differences of each tooth inclination, and correlation coefficients were generated for the inclination angles among the permanent and primary teeth. Most maxillary tooth-crown inclinations showed significant age-related differences, while only the second premolar and primary second molar differed significantly in the mandible. The maxillary molars were parallel to the corresponding mandibular molars and correlated with each other, but the primary molars were not. Significant correlations were found between inclinations of most permanent teeth, but not the primary teeth. Maxillary tooth-crown inclinations change during growth, but tooth-crown inclinations of the mandibular teeth do not.     

Long‐term evaluation of sealants applied with an invasive technique

Purpose : To study the retention of sealants applied to the permanent molars using an invasive technique. Methods : Sealants containing fillers were applied to 739 first permanent molars using an invasive technique. After a minimum period of 6 months (mean time lapse after treatment, 63.5 months; range 6 ? 121 months), the overall retention, marginal integrity, and marginal discolouration were evaluated according to the period after treatment, the operator's experience, and the location of the tooth (maxillary or mandibular). Results : The overall retention was 93.78%. The sealants and marginal integrity deteriorated with time and with less clinical experience. However, there was no significant difference between the maxillary and the mandibular teeth. Marginal discolouration occurred more frequently in the maxilla with time but there was no significant difference with the operator's experience. Conclusions : The retention rate and marginal integrity of sealants decreased with time and with less clinical experience of the operator, and more marginal discolouration developed in the maxillary teeth with time in comparison to the mandibular teeth.     

正畸治疗中磨牙的拔除和保留（五十三）——利用骨钉矫治生长发育期上颌后缩下颌前突型反

目的：评价骨钉前方牵引治疗对生长发育期上颌后缩下颌前突型反[牙合]病例的矫治效果。方法：选择替牙晚期和恒牙早期骨性Ⅲ类错病例8例,男2例,女6例,年龄11～14岁,平均12.2岁。均为上颌发育不足并伴有下颌、下牙弓轻度前突的凹面型,在双侧上颌颧牙槽嵴区植入骨钉,骨钉与牵引面罩的牵引钩相连,与[牙合]平面成向前下30°夹角,力值维持在350g左右,每日戴用时间为10～12h。有3例恒牙早期病例因牙列拥挤或下牙弓前突,设计对称拔除了上、下颌第二或第三磨牙,植入下颌磨牙骨钉以牵引排齐内收下牙弓。结果：8例患者前方牵引5～10个月,平均7个月,均有效解除前牙反[牙合]。结论：应用骨钉做前方牵引,牵引力通过上颌骨阻力中心,不会致颌骨出现异常旋转。牵引力完全作用在颌骨上,避免了对牙齿产生副作用。骨钉还可用于牵引上下颌牙列远中移动,减少上前牙唇倾并增强前方牵引对下牙弓的矫治作用。     

Plaque removal using a battery-powered toothbrush compared to a manual toothbrush

OBJECTIVE: To evaluate the effectiveness of battery-powered tooth brushing in removing plaque in Kuwaiti children. METHODOLOGY: The subjects were 30 boys, aged 9-11 years. Prior to the start of the study, the children had never used a battery-powered toothbrush. At baseline, plaque accumulation was assessed for manual tooth brushing and battery-powered tooth brushing (Oral-B Kids battery-powered). All subjects then used the battery-powered toothbrush for two weeks at home. Plaque accumulation was again assessed for both manual and battery-powered tooth brushing. Plaque accumulation was assessed using the Soparkar modification of the Quigley-Hein Plaque Index. Differences in pre- and post-tooth brushing plaque, and change from baseline, were the outcome measures evaluated. RESULTS: At baseline, there was no difference in plaque removal between battery-powered tooth brushing and manual tooth brushing, either in difference between pre- and post-tooth brushing plaque measures (p = 0.44) or in percentage change (p = 0.51). After two weeks of use, there was a statistically significant difference in plaque removal between battery-powered tooth brushing and manual tooth brushing, both in the difference between pre- and post-tooth brushing plaque measures (p = 0.01) and in percentage change (p = 0.006). Mean plaque removal by manual tooth brushing was 0.97 +/- 0.45, and mean plaque removal by battery-powered toothbrush was 1.23 +/- 0.56. Mean percentage change in plaque removal by manual tooth brushing was 33.5 +/- 16.05, and mean plaque removal by battery-powered tooth brushing was 43.0 +/- 18.82, which represented a 9.5% improvement for battery-powered tooth brushing compared to manual tooth brushing. CONCLUSION: After two weeks use of a battery-powered toothbrush, the plaque removal was enhanced compared to baseline and to manual tooth brushing. Battery-powered tooth brushing also enhanced manual tooth brushing ability.     

Maxillary and mandibular mesiodistal tooth sizes among different malocclusions in a sample of the Turkish population

The purpose of this study was to establish normative data for mesiodistal tooth crown dimensions with respect to malocclusions and gender differences in Turkish sample. The subjects were randomly selected and assigned to three malocclusion groups according to Angle's classification. Each group consisted of 100 individuals between the ages of 13 and 18 years with the following distribution: Class I, 42 males and 58 females; Class II, 52 males and 48 females; and Class III, 51 males and 49 females. An electronic digital calliper was used to measure the mesiodistal tooth width from the right second permanent molar to the left second permanent molar on both upper and lower study casts. For statistical evaluation, one- and two-way analyses of variance and post hoc Tukey's honestly significant difference (HSD) tests were performed. There were statistically significant differences for the maxillary canine (P < 0.001), first premolar (P < 0.05), second molar (P < 0.05), and mandibular canine (P < 0.01) for males, and for all maxillary teeth and the mandibular central (P < 0.05), canine (P < 0.001), and first premolar (P < 0.05) teeth in females among the malocclusion groups. When Angle's classification was evaluated, significant differences were determined, except for the first and second mandibular molars. All mesiodistal widths were also found to be statistically different according to gender dimorphism. A significant relationship was found between mesiodistal tooth size, Angle's classification, and gender. Therefore, tooth dimensions may play a crucial role in treatment planning and in achieving satisfactory interdigitation of the upper and lower dentition following the completion of orthodontic treatment.     

Fluctuating asymmetry of the permanent mandibular molars in a Japanese population

The purpose of the present study is to investigate the pattern of fluctuating odontometric asymmetry of permanent mandibular first and second molars in a Japanese population. Dental plaster casts of 112 (57 males and 55 females) Japanese undergraduate dental students were used. The mesiodistal and buccolingual diameters of the whole crown and trigonid and talonid crown components were taken on the left and right sides of the mandibular permanent first and second molars. Crown areas were also calculated. The fluctuating asymmetry (FA) value was obtained by dividing the absolute side difference by the absolute mean size of the left and right teeth: FA = abs (R?L)/((R + L)/2). Fluctuating asymmetry between mandibular first and second molars was significantly different with the mandibular second molar showing higher asymmetry in both males and females. Meanwhile, fluctuating asymmetry between males and females in the first and second molars was not significantly different in all measured dimensions. With regard to trigonid and talonid components, fluctuating asymmetry of the distal talonid area was significantly larger than the mesial trigonid area in the mandibular permanent first molar of males (P < 0.01), and asymmetry of buccolingual diameter of the talonid was also larger than that of the trigonid in the mandibular permanent second molar of males (P < 0.05). In conclusion, these findings suggest that the crown dimensions of later developing teeth in the mandibular molar tooth class and crown component in the same molar tooth show more asymmetry and, therefore, are more affected by external factors.     

Mesio-marginal findings at tilted molars. A histological-histomorphometric study

The aim of this study was to investigate the mesio-marginal findings at tilted molars (TM) by means of histological-histomorphometric evaluation. Eight lateral tooth bone segments with TM (six mandibular, two maxillary) from males aged 20-32 years were compared with those of eight samples with non-tilted molars (NTM) in males aged 18-35 years. In comparison with the NTM samples, the TM revealed a higher amount of supra- and subgingival plaque, a significantly higher total number of inflammatory cells (P < 0.05) and blood vessels (P < 0.05) in the connective tissue adjacent to the junctional epithelium, and a lower density and corono-apical width of gingival fibres. No significant differences (P > 0.05) were found between the mesio-marginal bone level of the TM (mean: 978 microns) and that of the NTM (mean: 1222 microns). In contrast, indications were found that TM may affect the disto-marginal bone level of the mesial tooth.     

The prevalence of pre-eruptive dentin radiolucencies in the permanent dentition

PURPOSE: Although intracoronal radiolucencies in radiographs of unerupted teeth have been reported for several decades, the prevalence of this condition remains unknown. This study determined the prevalence and associated dental conditions of permanent teeth showing pre-eruptive dentin radiolucencies in bite-wing radiographs of school children attending two school dental therapy training centers. METHODS: There were 1959 subjects (934 males and 1025 females), each providing a set of bite-wing radiographs which showed the crowns of unerupted permanent teeth. The mean age of the children at radiographic exposure was 7.8 +/- 1.79 years of age. RESULTS: 126 (6%) of subjects had radiolucencies in the crowns of pre-eruptive permanent teeth. Of the 9919 teeth viewed on the radiographs, 163 (2%) were affected. There were no significant racial and gender differences in the prevalence of the defects. Of the 126 subjects with dentin radiolucencies, 93 (74%) had only 1 affected tooth compared with 31 (25%) who had two teeth affected, and 2 (2%) who had 3 affected teeth. CONCLUSIONS: Within each tooth type, the highest tooth prevalence was found in the mandibular first molar (4%), followed by the mandibular first premolar (2%), the mandibular second molar (1%), mandibular second premolar (1%), maxillary first molar (1%), maxillary first premolar (1%), and maxillary second premolar (0.2%). In addition, the group with dentin radiolucencies had a high prevalence of ectopically-positioned teeth of 14% compared with only 2% in the group without the defect, suggesting that ectopic position may predispose a tooth to pre-eruptive radiolucent defects. Other common developmental and acquired dental conditions were also examined, but no significant differences were noted between groups with and without the pre-eruptive dentin radiolucencies.