上海地区189名正常乳牙(牙合)数字化模型测量与分析

目的：研究正常乳牙(牙合)的性别差异以及生长发育规律。方法：在上海市徐汇区多所幼儿园内，获取3～6岁正常乳牙(牙合)儿童189名，通过口内光学扫描获取乳牙列的三维数字化模型。利用三维逆向工程软件Geomagic Studio12.0提取数据，测量乳牙(牙合)数字化模型的前牙牙弓弧长(APC)、全牙弓弧长(APE)、前牙牙弓长度(LC)、全牙弓长度（LE）、前牙牙弓宽度(C-C)、后牙牙弓宽度（E-E）、乳牙冠近远中径、上下颌间隙。采用SPSS 22.0软件包对测量数据进行统计学分析。结果：上下颌乳牙弓各参数的测量值均为男性显著大于女性（P<0.05）。按照年龄分组，3岁组中男性的上颌APC、C-C、E-E显著大于女性（P<0.05）。4岁组中，除上颌LC外，所有其他参数均具有显著差异（P<0.05）。5岁组中，除上颌APE，下颌APC、LC、LE、C-C外，其余上下颌各项参数均为男性显著大于女性（P<0.05）。6岁组中，除下颌APE外，其余参数均无显著差异。除上颌乳侧切牙和下颌乳中切牙外，其他乳牙的近远中径均为男性大于女性（P<0.05）。3～6岁不同年...     

Angle Ⅲ类错(牙合)畸形牙弓、基骨形态及牙量的测量分析

目的 通过比较AngleⅢ类及个别正常殆青少年牙弓及基骨形态、牙量,为正畸临床诊断和治疗提供理论依据.方法 以上海地区个别正常(牙合)青少年60例为对照组(男女各30例);以Angle Ⅲ类60例为实验组(男女各30例).分别测量牙弓宽度及长度、基骨宽度及长度、牙量.用SPSS.13.0统计软件对测量结果进行统计分析.结果 (1)实验组上颌牙弓长度显著减小、下颌牙弓长度显著增加,牙弓宽度与对照组无显著差异.(2)实验组上颌基骨长度减小,下颌基骨长度显著增加;(3)实验组下颌牙量增加.结论 (1)AngleⅢ类患者存在上颌牙弓、基骨长度发育不足,下颌牙弓和基骨长度发育过度.在治疗中,可考虑使用相应治疗手段改善上颌牙弓和颌骨发育不足,同时还需注意抑制下颌过度生长.(2)Angle Ⅲ类患者下颌牙量增加,制订矫治计划时可考虑下颌牙齿减径.     

上颌尖牙埋伏阻生患者牙弓形态及拥挤度的研究

目的 上颌尖牙唇侧和腭侧埋伏阻生患者的牙弓宽度、长度、拥挤度与正常(牙合)个体之间是否存在差异.方法 经CT检查上颌尖牙埋伏阻生患者104名,年龄11-28岁.尖牙唇侧阻生患者57名,腭侧阻生患者47名,对其牙弓宽度、长度、拥挤度进行测量,并和正常(牙合)个体进行对照研究.结果 上颌尖牙唇侧埋伏阻生患者82.5%伴有牙弓中重度拥挤,上颌尖牙腭侧埋伏阻生患者57.4%的牙弓基本无拥挤.上颌尖牙埋伏阻生患者中,无论是唇侧埋伏还是腭侧埋伏,其牙弓长度与正常(牙合)无差异.双尖牙区牙弓宽度减小.结论 国人上颌尖牙埋伏阻生患者的牙弓宽度、长度、拥挤度的特点与白种人不同.     

江苏地区正常的牙及牙弓测量研究

目的 测量125名江苏地区正常人群的模型,建立江苏地区正常牙及牙列指数的平均值。方法 选取正常模型125副(男61副,女64副),用电子游标卡尺测量牙冠宽度、牙弓宽度及长度、腭盖高度,对测量结果进行统计分析。结果 江苏地区正常人群的牙冠宽度、牙弓宽度及长度、腭盖高度均为男性大于女性,Bolton指数及Pont指数无性别差异。上下颌6个前牙牙冠宽度总和、全部牙冠宽度总和具有相关性,上颌中切牙与上颌前段牙弓宽度之间亦存在相关性,且建立了直线回归方程。结论 牙冠形态、牙列指数存在种族、地区和性别的差异,临床上应参照本民族、本地区的标准。     

固定支架式扩弓器扩大上下颌牙弓初探

目的 探讨替牙(牙合)早期采用固定支架式扩弓器扩大上下颌牙弓矫治牙列拥挤的方法.方法 在1例9岁男童的上下颌同时黏结固定支架式螺旋扩弓器,上颌扩弓1个月,下颌扩弓2.5个月后,用"2×4"技术排齐拥挤的上下颌前牙,并用Hawley保持器保持.结果 上颌尖牙间宽度扩大5.4 mm,磨牙间宽度扩大9.0 mm;下颌尖牙间宽度扩大3.4 mm,磨牙间宽度扩大6.6 mm;上下牙列排列整齐,咬合关系良好.结论 对于基骨丰满、牙弓狭窄的轻度或边缘性中度牙列拥挤拟不拔牙患者,可在替牙(牙合)早期或中期试行上下颌同时扩弓治疗.     

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。     

成人腭裂患者牙弓形态的比较研究

目的 探讨腭裂畸形本身及修复术对牙弓形态发育的影响.方法 应用牙颌模型CT扫描测量系统,对比分析正常(牙合)成人、单侧完全性唇腭裂(UCLP)均已修复组以及腭裂未修复组成人患者牙弓形态特征.结果 腭裂术后组上颌牙弓各段宽度、牙弓前段长度均显著小于未手术组(P ＜ 0.01);未手术组上颌牙弓前段宽度、上下颌牙弓长度均显著小于正常组(P ＜ 0.01),而上下颌牙弓后段宽度大于正常组(P ＜ 0.001).结论 腭部裂隙对上颌牙弓发育的影响仅仅局限于牙弓前部裂隙邻近的区域,腭裂手术是造成上颌牙弓宽度缩窄的主要原因,同时也抑制了上颌牙弓前段长度发育.     

慢性牙周病患者牙弓宽度的测量和分析

目的:探讨牙周病患者与正常对照组牙弓宽度的差异及其意义。方法:选取48名慢性牙周病患者以及228名牙周正常的大学生,所有受试者均取研究模,选择双侧上颌第一前磨牙的近颊牙合角、下颌第一前磨牙的舌尖、上颌第一磨牙颊面沟的颊牙合面交点以及下颌第一磨牙舌面沟的舌牙合面交点为标志点,分别测量上述同名标志点之间的距离,依次记作上、下颌第一前磨牙牙弓宽度和上、下颌第一磨牙牙弓宽度。结果:牙周病患者的上、下颌第一前磨牙牙弓宽度以及下颌第一磨牙牙弓宽度明显小于大学生对照组(P<0.01),上颌第一磨牙牙弓宽度两组间未见明显差异(P>0.05)。结论:上、下牙弓宽度不调与牙周病有密切关系。     

唇挡对儿童牙弓及下颌骨生长发育的影响

目的研究下颌唇挡对替牙期及恒牙初期儿童下颌牙弓及下颌骨生长发育的影响,探索用下颌唇挡早期矫治下颌牙列拥挤的作用机理.方法选择替牙及恒牙初期下牙列拥挤患者30名(男14例、女16例),戴用下颌唇挡治疗6-10个月,进行治疗前后模型测量及X线头影测量分析.结果治疗后牙弓周长平均增加3.22mm,牙弓长度增加1.37mm,尖牙间宽度、第二双尖牙间宽度与第一磨牙间宽度分别增加1.63mm,2.35mm和1.83mm,切牙不齐指数减小1.66mm.表明切牙的唇移,牙弓宽度增大及第一磨牙远中直立对牙弓周长的影响较大.唇挡治疗后下颌平面角有所增加,但下颌骨位置与突度无明显改变.结论在儿童颌面部生长发育期间,下颌唇挡有助于增加下颌牙弓的长度与宽度,对治疗替牙期及恒牙初期下颌牙弓轻度或中度拥挤产生积极作用.     

Angle-Ⅲ类错骀畸形牙弓、基骨形态及牙量的测量分析

目的通过比较AngleⅢ类及个别正常验青少年牙弓及基骨形态、牙量，为正畸临床诊断和治疗提供理论依据。方法以上海地区个别正常骀青少年60例为对照组（男女各30例）；以AngleⅢ类60例为实验组（男女各30例）。分别测量牙弓宽度及长度、基骨宽度及长度、牙量。用SPSS．13．0统计软件对测量结果进行统计分析。结果（1）实验组上颌牙弓长度显著减小、下颌牙弓长度显著增加，牙弓宽度与对照组无显著差异。（2）实验组上颌基骨长度减小，下颌基骨长度显著增加；（3）实验组下颌牙量增加。结论（1）AngleⅢ类患者存在上颌牙弓、基骨长度发育不足，下颌牙弓和基骨长度发育过度。在治疗中，可考虑使用相应治疗手段改善上颌牙弓和颌骨发育不足，同时还需注意抑制下颌过度生长。（2）AngleⅢ类患者下颌牙量增加，制订矫治计划时可考虑下颌牙齿减径。     

Tooth size-arch length relationships in the deciduous dentition: a comparison between contemporary and historical samples

In a recent study, it was reported that maxillary and mandibular arch lengths were significantly shorter in a sample of contemporary children in the deciduous dentition compared with a historical sample from about 50 years earlier. The purpose of this study was to describe secular changes that might have occurred in tooth sizes and tooth size-arch length relationships in the same cohorts of contemporary and historical North American white children in the deciduous dentition. The 2 samples were similar in terms of geographic location, racial and ethnic backgrounds, and socioeconomic status. Both samples were restricted to white children with a normal overjet (<4 mm) and a normal anteroposterior molar relationship, no anterior open bite, and no crossbite. In addition, subjects were excluded if any permanent teeth were erupted. Measurements of mesiodistal tooth sizes and arch lengths of maxillary and mandibular arches were made, and tooth size-arch length discrepancies (TSALD) were determined. The results indicated that tooth sizes were generally similar in the 2 cohorts but slightly larger in contemporary children. Crowding, as measured by TSALD, was found to be common in the mandibular arch for contemporary children in the deciduous dentition of both boys and girls. Moreover, crowding was much more common and severe in contemporary children compared with children in the historical cohort. Further research is needed to determine whether the increase in mandibular crowding in the deciduous dentition will continue to be observed in the mixed and permanent dentitions and to further establish these possible secular trends.     

Comparison of dental arch measurements in the primary dentition between contemporary and historic samples.

The purpose of this study was to investigate secular changes that may have occurred in dental arch dimensions by comparing a sample of contemporary North American white children (born between 1992 and 1995) in the primary dentition to those children found in an earlier study of North American white children (born between 1946 and 1948). The sample of contemporary children has been followed prospectively since birth and was assessed at 4(1/2) to 5 years of age. Data for the historic sample were obtained from 5-year-old children who were enrolled in the Iowa Growth Study. The 2 samples were similar in terms of geographic location, racial and ethnic backgrounds, and socioeconomic status. To further enhance the comparison and to match the 2 groups, the 2 samples were restricted to white children with a normal overjet (<4 mm) and normal anteroposterior molar relationship, no anterior open bite, and no crossbite. In addition, individuals were excluded if any permanent teeth were erupted. Measurements of maxillary and mandibular arch lengths and intercanine and intermolar arch widths were made, with measurements of overjet and overbite. The results indicated that maxillary and mandibular arch lengths in both sexes were significantly shorter in the contemporary sample; all arch widths were significantly smaller in contemporary boys, but not in girls. These findings suggest that average arch dimensions may be smaller in contemporary children than in past generations. Further research is needed to determine whether smaller arch dimensions are associated with more crowding in the primary, mixed, and permanent dentitions.     

Dental arch dimensions in patients with unilateral cleft lip and palate

In this investigation, dental arch dimensions during different ages were studied in 72 children with unilateral cleft of the lip, alveolar process, and palate and were compared with those of normal children. All the children with clefts were treated surgically by surgeons of the Lancaster Cleft Palate Clinic. The dental arch dimensions were studied with the use of dental casts during the time of full deciduous dentition (3 to 4 years of age), mixed dentition (8 to 9 years of age), and permanent dentition (12 years of age). The major findings were: (1) all maxillary interdental widths and lengths were significantly smaller than the normal dimensions at all ages, except for intermolar width at age 12 years; and (2) the mandibular arch dimensions seemed to be related to changes in the maxillary arch; however, the influence of surgical procedures in the maxillary arch is not reflected severely in mandibular arch dental position.     

Relation between combined widths of incisors and dimensions of the dental arches

abstract – The correlation between the total widths of the incisors and the widths and lengths of the dental arches was studied in 149 boys and 175 girls, aged 8 years 10 months to 11 years 10 months. Eighty-two of the children were judged as having normal occlusion. The widths and lengths of the dental arches were positively correlated with the total widths of the incisors. The correlation coefficients were higher for the arch lengths than for the arch widths. The correlation was, however, only weak or moderate. Calculation of the width of the maxillary dental arch from the total widths of the incisors according to Pont's Index is of little diagnostic value because of the weak correlation between the variables. The determination coefficient between the total widths of the maxillary incisors and the anterior maxillary dental arch length was found to be 0.62, so that the total widths of the maxillary incisors is of some value for predicting the anterior dental arch length.     

替牙期骨性Ⅲ类单侧完全性唇腭裂患者修复术后口周力的分布特征

目的:通过与同龄非唇腭裂正常 儿童比较,研究替牙期骨性Ⅲ类单侧完全性唇腭裂(unilateral cleft lip and palate,UCLP)患者上下颌不同位点口周力的特征。 方法:选取替牙期6～12岁UCLP患者20例(男14例,女6例)为UCLP组;同龄正常 儿童21例(男14例,女7例)为对照组。采用口周肌压力采集系统测量每个研究对象息止 位时双侧上下颌中切牙、尖牙或乳尖牙、第一前磨牙或乳磨牙、第一恒磨牙的唇颊、舌腭侧龈缘的口周力。使用SPSS 25.0统计软件对数据进行统计分析。 结果:1．UCLP组上颌口周力裂侧大于非裂侧( P<0.05),下颌口周力两侧无差异( P>0.05)。2. UCLP组上颌口周力大于对照组( P<0.05),两组上颌唇颊侧的口周力均在第一前磨牙/乳磨牙区最大,在中切牙区最小。3. UCLP组下颌唇颊侧口周力小于对照组( P<0.01),下颌中切牙舌侧区UCLP组大于对照组( P<0.05)。4. UCLP组上颌牙弓内外口周力差值大于对照组( P<0.05),下颌差值小于对照组( P<0.01)。 结论:替牙期骨性Ⅲ类UCLP患者口周力较同龄非唇腭裂正常 儿童存在异常。     

Anomalies of deciduous teeth and findings in permanent dentition]

Prevalence of anomalies of deciduous teeth has been analyzed in the general population of Zagreb preschool children. The sample comprised 2,987 children from 3 to 6 years of age (1,582 boys and 1,405 girls). Hypodontia was found in 0.47%, hyperdontia in 0.10%, and double teeth in 0.43% of total sample. Total prevalence of all anomalies in the sample was 1.0%. The sample for the analysis of permanent dentition has been enlarged with the clinical sample of children having the same anomalies and comprised 48 children. In all children with anomalies of primary teeth the orthopantomograms were taken and the status of permanent dentition was analyzed. In children with hypodontia in primary dentition hypodontia of permanent teeth was found in 100% of cases. Patients with hyperdontia of primary teeth displayed anomalies in permanent dentition in 85.7%, while in children with primary double teeth, anomalies of permanent teeth were present in 61.1% of cases. Missing deciduous teeth were found in both jaws in only 8.7% of cases, and in 34.8% in permanent dentition. Symmetrical occurrence of hypodontia of primary teeth (i.e. in both sides of jaws) was significantly higher in boys (56.3%) than in girls (28.6%). In permanent dentition symmetrical occurrence of hypodontia was significantly higher than in primary dentition (81.3% in boys and 57.1% in girls). The most frequently missing primary teeth were maxillary lateral incisors (48.8%) followed by mandibular central incisors (34.9%). Hyperdontia of primary teeth has been found only in boys, and it related only to the maxillary lateral incisors. Anomalies of deciduous teeth show a high degree of association with the finding in the permanent dentition.(ABSTRACT TRUNCATED AT 250 WORDS)     

正常[牙合]乳牙期腭生长变化的分析研究

目的：研究正常[牙合]乳牙期儿童腭生长特点。方法：采用3D测量分析方法,用数学多项式拟合126例西安地区汉族正常儿童腭的生长图象,对其形态和大小分别按年龄和性别分组进行分析研究。结果：1）腭部大小的改变主要体现在3~5岁之间,3~4岁、4~5岁间差异并不明显;2）随年龄增长,尖牙间腭高度下降,但腭长度增加;3）尖牙间距随年龄增长并不明显;4）牙弓宽度和腭宽度存在性别差异,男性测量值普遍大于女性;5）腭形态的改变：随年龄增长变得更高;男性的腭部形态要宽于女性。结论：乳牙期腭的形态和大小受年龄和性别的影响,在三维方向上均会出现变化。     

扩弓辅弓与改良横腭杆扩大上颌牙弓的临床效果比较

目的比较扩弓辅弓和改良横腭杆扩大上颌牙弓的效果。方法分别应用扩弓辅弓与改良横腭杆对35例患者上颌牙弓进行扩弓,比较2组矫治前后的牙弓宽度改变。结果使用扩弓辅弓的病例第一前磨牙扩弓宽度变化不明显,增加2 mm左右,第二前磨牙和第一磨牙的磨牙宽度均有明显扩大,增加4 mm左右;使用改良横腭杆的病例第一、二前磨牙及第一磨牙间宽度均增加4 mm左右。结论上颌牙弓轻中度狭窄的病例采用扩弓辅弓和改良横腭杆扩弓均有较好的扩弓效果,可以根据各自的特点选择合适的病例。     

A longitudinal study on growth and development of dental arches of primary, mixed and permanent dentitions

In dental clinic for children, criteria for growth and developmental changes related to increases in the width and length of the dental arch at the primary, mixed, and permanent dentition stages are essential. This study was carried out to measure the width and the length of normal dental arch and to make detailed observations of growth and developmental processes in the dental arch at each dentition stage. Materials were serial study casts of the maxilla and the mandible taken every 2 month from 127 children (74 boys and 54 girls). The casts were made from 6 months after birth until the age of 15. Measurements of the width of the dental arch were made between bilateral teeth of the same tooth type, both deciduous and permanent. The length of the dental arch was measured on the basis of the perpendicular distance from the contact point of mesial surfaces of central incisors to a line between bilateral teeth of the same tooth type. Measured values were categorized according to either chronological age or tooth age on the basis of the eruption of the central permanent incisors. The indices of the dental arch with relation to the width and the length at each dentition stage were calculated for the sake of partial and total observations of alterations in dental arch form. The results were as follows: 1) In terms of chronological age, until 1 year before the eruption of permanent replacements, the width of the dental arch gradually decreased in both the maxilla and the mandible in the regions of the deciduous central and lateral incisors. Increasing slightly from about the age of 6 years and the period of mixed dentition, the width of the dental arch remained stable until the permanent dentition stage. From the primary dentition stage, the width of the dental arch in the region of the maxillary and mandibular canines and first and second molars gradually increased. Therefore it remained stable until the eruption of permanent dentition. The width in the region of the permanent maxillary and mandibular first molars gradually increased and attained a stable condition at about 12 years of age. In males, the width in the area of the maxillary secondary molars decreased slightly and tended to decrease in the mandible. In females, on the other hand, the width showed a tendency to increase with advancing ages. With the exception of the second permanent molars, the width between the distance of bilateral teeth were consistently larger in males than in females.(ABSTRACT TRUNCATED AT 400 WORDS)