右下第一恒磨牙异位萌出伴含牙囊肿一例

患者,女,8岁,主因右下六龄齿未萌出来北京大学口腔医院儿科就诊。其余象限六龄齿均已萌出。口内检查可见右下第二乳磨牙牙冠完整,叩痛（-）,不松,远中粘膜色正常,无膨隆（图1）。根尖片示：右下第二乳磨牙远中根大部分吸收,右下第一恒磨牙牙根发育至Nolla第8期,近中边缘嵴阻生在右下第二乳磨牙远中根下方。     

下颌第一磨牙五根管1例

患者,男,28岁,主诉右下后牙冷热刺激痛,夜间隐隐作痛1周余。检查：右下第三磨牙前倾位阻生,冠周无红肿,右下第二磨牙远中颌面呈黄褐色,探诊质硬,冷测（-）,右下第一磨牙颌面深龋,探敏感冷热刺激痛（＋）,叩诊（-）,无松动,     

下颌第一磨牙五根管1例

患者,女,26岁,2006年10月19日下午,来我院口腔牙体牙髓科就诊。主诉:右下后牙固定桥脱落,牙龈肿痛,要求冲洗消炎;查:右下5缺失,右下4、5、6烤瓷桥固定修复,修复体松脱数日,右下6残冠,旧充填体脱落,继发龋( ),叩( -),颊侧牙龈可见瘘管。X线片显示:右下6根分歧病变,根尖阴影,曾做     

土家族下颌第四磨牙1例报道

患者,女,37岁,土家族。因右下后牙肿痛反复发作一年余来我科就诊。口腔检查：右下第二磨牙远中邻殆面深龋,耠面见少许残留充填物,探（-）,叩（＋＋）,松（Ⅲ°）。右下第三磨牙垂直中位阻生,冠周无红肿及异常分泌物,牙冠远中见约2mm×2mm牙体组织,略高于右下第三磨牙耠面。     

下颌第二前磨牙异位阻生至第三磨牙远中1例

正患者,男,29岁,要求拔除右下后牙来我院外科就诊。患者数月来右下后牙牙龈反复胀痛,大张口时疼痛加重,影响进食,自服消炎药可以缓解,现症状明显减轻,于2011年7月5日来我院外科要求拔除右下后牙。自述替牙期间右下一颗乳牙脱落后无恒牙萌出。口腔专科检查:颌面部左右对     

先天性面斜裂(四例报告)

我院自1980年以来收治面斜裂患者四例,双侧,单侧各二例,经手术治疗外形恢复较满意。病例报告例1 孙某,男,7个月,汉族。因双侧面斜裂于1986年9月13日入院。右侧为不完全裂,裂隙自右上唇经鼻翼外侧向上至右下睑缘下方1cm。右鼻翼部分缺损,右鼻孔先天闭锁。左侧为完全裂,唇裂位置     

下颌骨含牙软骨母细胞型骨肉瘤1例

1病例报告 患者女,16岁,因右下颌骨无痛渐增性肿物2个月余于2006年7月17日入我科。3个月前因右下后牙牙龈有一肿物伴右下第一前磨牙松动就诊于当地诊所,行根尖x片示：右颏孔下方-“埋伏牙”影。行肿物穿刺,抽出少量淡黄色液体,即在局麻下行“右下第一前磨牙拔除术”及“导萌术”,术后牙龈肿物消失,但“埋伏牙”未萌。     

牙周植骨术在临床中的应用一例

牙周病是指发生在牙齿支持组织的疾病,是口腔最常见的疾病之一,在世界范围内均有较高的患病率.我国也有80-97%的成年人群有牙周的问题.近年来,诊所在牙周治疗及预防中做了大量的工作,让患者明白牙周病预防的重要性,做到早预防,早发现,早治疗.随着牙周病预防的普及,还开展了牙周手术的工作,尤其是牙周植骨术取得了令人满意的效果.牙周植骨术是采用骨或骨的替代品等移植材料来修复因牙周病造成的牙槽骨缺失的方法.属于再生性牙周手术,目的在于通过移植材料促进新骨形成,修复骨缺失,恢复牙槽骨的解剖形态,以达到理想的骨再生或新附着性愈合.适用于二壁及三壁骨下袋.病例:患者邓某,男,1955年出生,2003年11月因牙龈出血肿痛而就诊.口腔检查:牙石+++,牙龈红肿探之易出血,龈下牙石.双侧后牙均有松动(+),全景X光片显示:全口牙槽骨呈水平吸收达根长1/3左右,左下4和6近中根角形吸收达根尖1/3,右下5近中右下6远中角形吸收.治疗计划:1龈上洁治,龈下刮治.2左下第一前磨牙、第一磨牙;右下第二前磨牙、第一磨牙牙周翻瓣术.经过龈上龈下洁治后患者感觉良好,2006年实施左下第一前磨牙、第一磨牙和右下第二前磨牙、第一磨牙牙周翻瓣植骨术,手术顺利.两年跟踪复诊临床效果理想,患者满意.2008年全景X光片显示:左下46右下56的角形吸收区新骨形成,口腔检查牙龈色形正常.     

牙痛并胸肩部疼痛一例报告

患者:贺×,女,汉族,24岁,因右下后牙疼痛时,右胸、肩区出现剧痛于1988年5月19日来我科就诊。 病史:十日前因右下后牙突然疼痛,引起胸、肩区剧痛。牙痛缓解后,症状缓解,做过针灸治疗无效。     

下颌骨神经纤维瘤1例

神经纤维瘤多见于软组织,发生于颌骨罕见,现将我科收治的1例报告如下. 患者,女,46岁,因"右下后牙区疼痛1年"就诊.一年前,患者右下后牙区不明原因出现持续性疼痛,就诊于当地医院,诊断为71急性牙髓炎,接受牙髓治疗后无明显好转,将其拔除,但疼痛仍无缓解.     

一例罕见的眶部——颌下联合电击伤

颌面部电击伤会对患者造成严重的功能障碍。我院1例涉及右侧眼眶部、颧面部及左侧颌下区的电击伤,患者右眼失明,在清创术中被摘除眼球。右侧眼眶部创面用左侧上臂内侧游离皮瓣修复,之后取左侧大腿内侧中厚皮片覆盖左侧上臂内侧皮瓣供区及左侧颌下区创面。1个月后随访,患者右侧眶部外形恢复良好,左侧颌下区创面亦无继续感染迹象。     

Evaluation of an articulated measuring apparatus for use in the oral cavity

The aim of this study was to evaluate the trial Teaching Robot for the development of a contact-type measuring apparatus for using directly in the oral cavity. A standard model was used to mimic the dentition by placing an arrangement of three bearing balls. The diameters of the balls were measured. A practical dentition model was used. The coordinates were measured on the top of the buccal cusp of the right and left first premolars and the distal contact points of the right and left first molars and the mesial contact point of the right incisor. The arch width and length were calculated. The diameters of the bearing balls and the widths and lengths of the dental arches were not significantly different from the results of the XYZAX G-800D. Therefore, we suggest that the trial Teaching Robot has superior efficiency for measurements in oral cavity.     

Mathematical definition of the curve of Spee in permanent healthy dentitions in man.

The intrinsic morphology of the mandibular curve of Spee (i.e. independent from reference planes) was studied in 50 men and 45 women with sound dentitions. Left and right curves were reconstructed by a second-order quadratic interpolation of buccal cusp tips. Gender differences were found in both sides, while side differences were found only in the male sample. Male and female curves had similar concavities, but the position of the interpolating second-order quadratic curve relative to the dental arch was significantly different. The right and left male sides showed different concavities, the right-hand side being flatter than the left. Male curves appeared larger than female ones, and the left-hand side was significantly larger than the right regardless of gender. The reported second-order quadratic curves could be used as reference for prosthetic and orthodontic reconstructions.     

Comparative Measurement of Mesiodistal Width of Six Anterior Maxillary and Mandibular Teeth in Rajasthan Population

The purpose of the study was to determine the mesiodistal width of six anterior teeth for better esthetics and good tooth arrangement in a cross section of Rajasthan population. The mesiodistal dimension of central, lateral incisor and canine on right and left sides was measured in 250 males and 250 females, these readings were used to determine the mean, minimum and maximum maxillary/mandibular teeth ‘anterior ratio’, difference in mesiodistal width, combined mean mesiodistal width, the number and percent of similar teeth of maxilla and mandible. It was observed from the present study that there is variation in mesiodistal width in right and left sides signifying that the anterior teeth are not mirror images of one another. Male subjects have greater mesiodistal width than female subjects and right side dominates in most of the readings indicating that mesiodistal width is greater on right side than on left side. Percentage variability and sexual dimorphism are also important findings of this study. This study can prove helpful in replacement of artificial teeth of prosthesis in this cross section of population.     

Changes in cortical bone mineralization in the mouse mandible with regenerated condyle

The objective of this study was to evaluate the effects of condylectomy and of a functional appliance on the mineral content, density, and area of the mandibular cortical bone in a growing mouse model. In the condylectomy group, a unilateral condylectomy was performed on the right side of the mouse mandible. In the condylectomy + appliance group, a functional appliance was used to reposition the mandible after the unilateral condylectomy. All mice were killed 4 wk after surgery. Each mandible was then subjected to analyses of cortical bone mineral content (CRT_CNT), cortical bone density (CRT_DEN), and cortical bone area (CRT_A) by peripheral quantitative computed tomography (pQCT). The CRT_CNT, CRT_DEN, and CRT_A values were significantly lower in the condylectomized mandible (right side) than in the non-condylectomized mandible (left side). However, in the condylectomized animals in which a functional appliance was used, the CRT_CNT, CRT_DEN, and CRT_A values became higher than those in the mice treated with condylectomy alone. No significant differences were found in the CRT_CNT, CRT_DEN, and CRT_A between non-condylectomized (left side) mandibles, mandibles treated with condylectomy + functional appliance (right side), and control mandibles. It was thus shown that a functional appliance used to reposition the condylectomized mandible forward in a symmetric position induced improvement of the cortical bone in a mouse model in terms of cortical bone mineral content, density, and area.     

黏弹性补充疗法治疗颞下颌关节骨关节病的实验研究

目的　通过动物模型观察黏弹性补充疗法治疗颞下颌骨关节病的效果。方法　用基质金属蛋白酶 - 1腔内注射制备兔的双侧颞下颌关节骨关节病的动物模型 ,2 4只兔随机分为 3组。A组行冲洗治疗 ,B组行黏弹性补充治疗 ,C组二者联合应用。分别于建模后 2、3、4周对左侧关节治疗 3次 ,右侧为对照。第 8周末处死动物 ,切取双侧关节 ,苏木精 伊红染色 ,光镜观察。结果　A组左侧关节病变与右侧差异无显著性。B组和C组左侧关节病变明显轻于右侧。C组的病变比B组轻。结论　黏弹性补充疗法能抑制骨关节病的发展 ,与关节冲洗术联合应用有协同作用。     

Effects of experimental leg length discrepancies on body posture and dental occlusion

The purpose of this study was to quantitatively evaluate the effects of experimental leg length discrepancies on body posture and dental occlusion. Thirty asymptomatic subjects (15 males and 15 females, ages 19-33, mean age 25.6 years) were included in this study and randomly assigned to one of two groups based on a table of random numbers. The only difference between group A and group B was the sequence of testing. Experimental leg length discrepancies were provided by using ten types of insoles with heights ranging from one to ten mm at one mm intervals, placed under both feet. The MatScan (Nitta Corp., Osaka, Japan) system was used to measure changes in body posture (center of foot pressure: COP) while subjects maintained the following three postural positions: 1. natural standing posture (control); 2. control with a heel lift under the right foot; or 3. control with a heel lift under the left foot. The T-Scan II system (Nitta Corp., Osaka, Japan) was used to analyze the results of changes in dental occlusion (center of occlusal force: COF) in the above-mentioned three postural positions. When subjects used a heel lift of six mm or more under the right foot, lateral weight distribution (LWD) shifted to the right side compared to the control (p<0.05). When a heel lift of four mm or more was used under the left foot, LWD shifted to the left side compared to the control (p<0.05). When subjects used a heel lift of eight mm or more under the right foot, occlusal force shifted to the right side compared to the control (p<0.05). When subjects used a heel lift of seven mm or more under the left foot, occlusal force shifted to the left side compared to the control (p<0.05). Based on these findings, it was concluded that leg length discrepancy affected body posture and dental occlusion.     

Examination of the relationship between mandibular position and body posture

The purpose of this study was to evaluate the effect of changing mandibular position on body posture and reciprocally, body posture on mandibular position. Forty-five (45) asymptomatic subjects (24 males and 21 females, ages 21-53 years, mean age 30.7 years) were included in this study and randomly assigned to one of two groups, based on the table of random numbers. The only difference between group I and group II was the sequence of the testing. The MatScan (Tekscan, Inc., South Boston, MA) system was used to measure the result of changes in body posture (center of foot pressure: COP) while subjects maintained the following 5 mandibular positions: (1) rest position, (2) centric occlusion, (3) clinically midlined jaw position with the labial frena aligned, (4) a placebo wax appliance, worn around the labial surfaces of the teeth and (5) right eccentric mandibular position. The T-Scan II (Tekscan, Inc., South Boston, MA) system was used to analyze occlusal force distribution in two postural positions, with and without a heel lift under the right foot. Total trajectory length of COP in centric occlusion was shorter than in the rest position (p < 0.05). COP area in right eccentric mandibular position was larger than in centric occlusion (p < 0.05). When subjects used a heel lift under the right foot, occlusal forces shifted to the right side compared to no heel lift (p < 0.01). Based on these findings, it was concluded that changing mandibular position affected body posture. Conversely, changing body posture affected mandibular position.     

Distance alterations of dies in sagittal direction in dependence of the die material

The distance alterations between the first premolar and second molar in the sagittal direction were measured on complete arch models in two planes. Two dental stones, three resins, and silver-plating were used to make reproductions of a master cast under standardized conditions. Special emphasis was directed to the distinction between the right half of the model with teeth between the dies and the left side edentulous between the dies. The stones Die Keen and Fuji Rock showed the least distortion, identical bilaterally. The epoxy resins Blue Star E and Metapox exhibited a significant distinction between the right and the left sides. In addition to the pronounced distance reduction caused by polymerization shrinkage, a divergence between the dies and the model base on the side with teeth was measured. This phenomenon was also observed with polyurethane Blue Star P resin, but was less substantial. Silver-plating recorded a slightly greater reduction in distance between the dies than Fuji Rock. However, no significant differences were found between both sides.     

Three-dimensional changes in the condyle during development of an asymmetrical mandible in a rat: a microcomputed tomography study.

A rapidly growing postnatal animal model was used to study changes in the calcified tissue of the mandibular condyle during altered muscle function. A maxillary occlusal splint was designed to shift the mandible laterally (left) during closure. Groups of 5 Wistar rats were killed at 5, 9, 15, 21, 30, and 40 weeks (n = 30), with an equal number of controls. The experimental animals developed shorter, asymmetrical mandibles compared with the control animals. The left condyle became larger and thicker than the right condyle. Microcomputed tomography assessment of the left and right condylar trabecular bone indicated that both had less bone volume than the control condyle. The right masseter muscle significantly lost fiber size and type IIA oxidative fibers, suggesting that the right masseter muscle was used with less tension development. In contrast, the left masseter maintained its fiber size and was similar to the control masseter fiber diameters. Comparison in the sequence of changes indicated that the morphologic changes occurred first in the ramus (age, 5 weeks), before the corpus (age, 15 weeks), and before changes in masseter fiber size and composition (age, 9 weeks). This study showed that both the mandible and the condyle modified their shape and size, as well as the trabecular bone of the condyle, during shifting of the mandible to one side as it closed.