上颌窦无症状性巨型结石

上颌窦结石的大多数患者均有疼痛、鼻塞、鼻衄、鼻溢、鼻后滴涕,上颌窦压痛和/或上颌窦口腔痿等临床症征。本文报道1例上颌窦巨型结石,无上述任何症状,为常规X线检查时意外发现的病例。患者,女,32岁。曲面体层X线照片显示左上颌窦有一清晰的卵圆形团块。追问病史,否认任何自觉症状。体检:患者面部对称,左上颌骨无肿胀,上颌窦前壁无压痛,口内也未见上颌骨及颊侧牙槽骨肿胀,牙无叩痛,电测活力正常。华氏位片和口内片显示左上颌窦     

CBCT和曲面体层片在上颌后牙区种植治疗中的诊断价值比较

目的:比较牙颌面专用锥形束CT(CBCT)与普通X线曲面体层片在上颌后牙区种植治疗中的诊断价值.方法:对75例(89侧)上颌后牙区种植牙治疗患者采用CBCT进行种植前后的影像学检查,得到上颌骨多层面冠状及矢状位影像.将其与曲面体层片进行比较,判断其与CBCT检查结果的一致性.采用SPSS11.5软件包对数据进行X2检验.结果:牙槽骨量不足的阳性检出率,CBCT和曲面体层分别为30.34%和16.85%,P=0.034,差异有统计学意义;种植体未发生骨结合的检出率,CBCT和曲面体层片分别为4.95%和11.88%,P=0.413,差异无统汁学意义.结论:CBCT与曲面体层片相比,可以更准确评估术前上颌后牙区的牙槽骨骨量,并可在术后检查中更清晰地反应种植体周围骨质.     

曲面体层片与锥形束CT比较分析上颌后牙牙根与上颌窦的关系

目的 研究曲面体层片与锥形束CT(cone beam computer tomography,CBCT)判断上颌后牙牙根与上颌窦关系的准确性,为临床医师根据曲面体层片信息治疗上颌后牙区相关疾病提供参考.方法 纳入80例符合标准的患者(牙根数671个),以锥形束CT为标准,在曲面体层片及锥形束CT片上测量上颌后牙根尖到上...     

口腔曲面体层片判断上颌牙根突入上颌窦的敏感度与特异度分析

目的:评价口腔曲面体层片判断上颌牙根突入上颌窦的敏感度与特异度.方法:纳入110例患者,男42例,女68例;年龄15～36岁,上颌第二磨牙已完全萌出,拍摄全牙列锥形束CT(CBCT)及口腔曲面体层片.分别根据2种影像数据观察上颌尖牙、上颌第一前磨牙、上颌第二前磨牙、上颌第一磨牙及上颌第二磨牙牙根是否突入上颌窦.以CBCT观察结果为金标准,收集四格表资料,计算口腔曲面体层片进行判断的敏感度、特异度、准确度、阳性似然比、阴性似然比及牙根进入上颌窦的发生率.结果:口腔曲面体层片判断牙根是否突入上颌窦的敏感度分别为上颌尖牙100％,上颌第一前磨牙100％,上颌第二前磨牙96％,上颌第一磨牙99％,上颌第二磨牙96％.特异度分别为上颌尖牙94％,上颌第一前磨牙92％,上颌第二前磨牙84％,上颌第一磨牙55％,上颌第二磨牙67％.结论:口腔曲面体层片判断上颌牙根是否进入上颌窦的敏感度高,但是对于第二前磨牙、第一磨牙及第二磨牙判断的特异度较低.正畸临床不能以之作为上颌后牙支抗设计的依据.     

移位牙致上颌窦含牙囊肿1例

移位牙指牙齿的形成与萌出过程中 ,受到全身或局部因素的干扰而不能萌出到正常位置的牙齿。而由上颌第三磨牙移位于上颌窦与后组筛窦交界处致上颌窦含牙囊肿临床上较罕见 ,现报告如下。患者 ,男 ,2 0岁 ,因左侧颌面部膨隆 10个月而入院。既往面部无外伤异物史。查体 :左侧颌面部肿胀明显。左眼球未见突出、活动自如、无复视。双眼视力 1.0。左鼻腔狭窄、外侧壁内移、无异常分泌物。口内见 |8未萌 ,|5 6 7龈颊沟隆起 ,扪之有“乒乓球样”感 ,穿刺获棕褐色半透明状液。左上颌牙无松动 ,咬合关系正常。全口牙位曲面体层摄影及上颌华氏位X线片…     

埋伏阻生牙曲面断层片诊断方案的探讨

目的 :探讨对于颌骨不同部位的埋伏阻生牙应用不同平片透照技术以达到精确直观的X线影像 ,提高诊断的准确率。方法 :对32例埋伏阻生牙及多生牙患者使用牙片、咬合片、全景片、全景断层片、头颅侧位片、埋伏牙切线位片、全景上颌窦侧方片对埋伏阻生牙定位。结果 :通过单全景、双曲面断层及多断层三种曲面断层片诊断方案埋伏阻生牙及多生牙在颌骨中的位置 ,牙轴的方向 ,牙体形态、与周围解剖组织的关系得以准确显示。结论 :本研究平片诊断方案能比较准确地对颌骨内埋伏阻生牙及多生牙定位 ,为正畸及口外治疗方案的确定提供可靠依据。     

面中部骨折后上颌窦腔密度变化的影像学评价

目的:分析面中部骨折术前、术后及复诊时X线平片上颌窦密度的变化情况,结合病历记录,揭示创伤后上颌窦积血的变化特点.方法:搜集1995～2006年北京大学口腔医院颌面外科收治的面中部骨折病例中术前、术后或复诊时X线片显示有上颌窦密度变化的病例.分析伤后、术后及复诊时华特位片上颌窦密度变化的情况.结果:符合条件的病例219例,男性165例(75.3%),女性54例(24.7%).年龄:3～78岁,中位年龄29岁.78例复诊患者中,复诊时51例(65.38%)上颌窦恢复清亮;19例(24.36%)上颌窦密度较术后减低;8例(10.26%)上颌窦密度无改善甚至较术后增高.其中4例病历记载有明确的上颌窦炎症病史,另外4例可疑存在上颌安炎症,但病历无相关诊治记载.结论:大部分上颌窦骨折继发的上颌窦积血在伤后或术后一段时间内可以自行吸收,部分病例可能出现上颌窦炎症性改变.     

下颌阻生第三磨牙与下颌管位置的曲面体层X线片和锥形束CT观察

目的 观察分析在曲面体层x线片上人群中下颌阻生第三磨牙(impacted mandibular third molar,IMTM)与下颌管位置关系的类型,并对二者关系密切的病例行锥形柬CT(conc beam computed tomography,CBCT)检查,了解二者实际位置关系.为临床制定IMTM拔除手术方案提供参考.方法 观察390例(645侧)曲面体层X线片,将IMTM与下颌管的位置关系的影像分为3种类型:①无接触类,二者影像无任何重叠或接触;②点状接触类,二者之间影像仅为点状接触;③部分重叠类,二者影像部分重叠或有较大范围接触.统计3种类型的构成比.曲面体层X线片显示IMTM与下颌管影像呈部分重叠或较大范围接触的部分病例行CBCT检查,观察曲面体层X线片IMTM与下颌管关系密切者中,IMTM实际突破下颌管壁所占的比例.结果 390例(645侧)IMTM的曲面体层X线片影像中,无接触类441侧(68.4%);点状接触类149侧(23.1%);部分重叠类55侧(8.5%).对31例(50侧)曲面体层X线片上显示IMTM与下颌管呈部分重叠或较大范围接触的CBCT检查发现,25侧(50%)IMTM突破下颌管壁.结论 ①曲面体层X线片可以排除90%以上IMTM与下颌管关系不密切的病例;②曲面体层X线片IMTM与下颌管影像呈部分重叠或较大范围接触表现的病例有必要行CBCT进一步检查.     

锥形束CT辅助诊断慢性牙周炎牙槽骨缺损的准确性研究

目的 评价锥形束CT在辅助诊断慢性牙周炎牙槽骨缺损中的准确性及其与根尖X线片、曲面体层X线片和临床检查结果的一致性,以期为锥形束CT在辅助诊断慢性牙周炎骨缺损中的应用提供依据.方法 采用单纯随机抽样法纳入2012年12月至2013年12月就诊于西安交通大学医学院附属口腔医院牙周黏膜科并确诊为慢性牙周炎的患者75例,分别进行锥形束CT、根尖X线片及曲面体层X线片检查,用华海MedViewer及EzlmPlant软件测量牙槽骨缺损的高度,同时行全口牙周探诊检查,确定附着丧失水平及釉质牙骨质界至牙槽嵴顶的距离,作为影像学检查结果的临床评判指标.对临床测量值及锥形束CT测量牙槽骨的缺损值行配对t检验,采用单因素方差分析评价4种方法检测近远中牙槽骨缺损的结果,以P＜0.05为差异有统计学意义.结果 共纳入1 494颗牙,8 964个位点,3种影像学方法中仅锥形束CT可以检测出唇(颊)或舌(腭)侧牙槽骨破坏;对近远中向牙槽骨缺损的测量结果显示,锥形束CT[近中:(5.5±0.4)mm,远中:(5.6±0.8)mm]与根尖X线片[近中:(5.1±0.6)mm,远中:(5.1±0.8)mm]、锥形束CT与全口曲面体层X线片[近中:(4.9±0.4)mm,远中:(4.9±0.8)mm]的测量结果相比差异均有统计学意义(P值均＜0.01),临床探诊[近中:(5.5±0.6)mm,远中:(5.5±0.6)mm]与根尖X线片及全口曲面体层X线片相比差异亦有统计学意义(P值均＜0.01),但临床探诊与锥形束CT的测量结果相比差异无统计学意义;锥形束CT与临床探诊对不同区域1 494颗牙齿牙槽骨缺损差异的检出情况一致,两种方法检测不同区域牙齿及1 494颗牙不同位点的牙槽骨缺损差异均无统计学意义(P值均＞0.05),两种方法不存在牙位及位点差异性.结论 锥形束CT与临床探诊在评价不同牙位及不同位点的牙槽骨缺损中一致性最高;锥形束CT在判断慢性牙周炎骨缺损方面与临床检查结果具有较高的一致性,优于根尖X线片和曲面体层X线片.     

全颌曲面体层片和根尖片测量线距准确性的对比研究

目的：探讨全颌曲面体层片和根尖片在测量颌骨牙根区域线距时准确性的差异。方法：选取20例12～16岁的恒牙列正畸患者的记存模,在模型中嵌入5.00 mm钢珠作为标准参照物,分别拍摄全颌曲面体层片和根尖片,测量磨牙区、前磨牙区、尖牙区和切牙区影像中钢珠的水平径和垂直径,比较两种拍摄方法的测量值在各区域的变化,并与钢珠的真实值进行比较。结果：全颌曲面体层片测量值的失真率在后牙区较小,前牙区较大;根尖片的所有测量值中,失真率除少数前牙区较大外,其余区域的测量值接近;全颌曲面断层片水平测量值失真率较垂直测量值失真率大,根尖片则两者相近;全颌曲面断层片测量值较根尖片更接近实际值,但影像的放大率变化较大,而根尖片影像的放大率较大,但其失真率更恒定。结论：如使用标准参照物校正测量值,根尖片对颌骨内牙根区域线距的测量结果更可靠。     

Midfacial fractures in dental panoramic radiography

The purpose of the present study was to evaluate the ability of panoramic radiographs to demonstrate facial fractures. Radiographs of eighty-two patients were analyzed retrospectively in cases in which both panoramic and conventional skull radiographs were available. One hundred thirty fractures within the middle third of the facial skeleton were identified, excluding nasal and mandibular fractures. In 64 per cent of the cases structural alterations suggesting fracture were detectable on panoramic radiographs; however, the interpretation of fractures on panoramic radiographs was much less certain than on conventional skull radiographs. The use of panoramic radiographs alone was often inadequate for diagnosis of many fractures outside the mandible.     

The application of panoramic zonography to the diagnosis of maxillofacial fractures

Traditionally, multiple radiographic views and techniques were required to elucidate the nature and extent of fractures of the maxillofacial complex. As a result, patient cost in terms of time, expense, manipulation, and radiation exposure scaled upward. Synthesis and interpretation of the fragmented bits of information from multiple films also constituted a labor-intensive process. A new imaging modality, panoramic zonography, provides precise anatomic imaging of preselected areas of interest with minimal radiation exposure. The usefulness of this technique in the diagnosis, treatment, and follow-up of traumatic events in the mandibular and maxillofacial regions is illustrated by a series of cases.     

Diagnosis of jaw and dentoalveolar fractures in a traumatized patient with cone beam computed tomography

Abstract –  The purpose of this case report is to discuss and illustrate the clinical usage of Cone Beam Computed Tomography (CBCT) for the diagnosis of maxillofacial fractures in a traumatized patient. In this presentation, a 30‐year‐old male patient who was referred to Oral Diagnosis and Radiology Department with a limitation of mouth opening was reported. The history of the patient revealed a traumatic injury on his face because of a fall. The patient was initially examined by a medical practitioner in the emergency department of a public hospital. According to 2D cephalometric analysis, no fracture existed. Panoramic radiograph and postero‐anterior reverse‐town showed bilateral condyle fractures. In addition, a fracture in the left mandibular incisor region could clearly be detected on the panoramic radiograph. For further diagnosis, digital images were taken with CBCT. Cross‐sectional views showed two vertical fracture lines on the alveolar bone between teeth numbers 17, 18 and 14, 15. A palatal root fracture was observed associated with tooth number 18. A fracture line in the left mandibular incisor region as well as bilateral condyle fractures could be seen clearly on CBCT views. CBCT is becoming a popular tool in modern dental practise. In the diagnosis of dentoalveolar fractures, CBCT has made it possible for the practitioner to get more detailed information.     

Efficacy of panoramic radiographs in the preoperative planning of posterior mandibular implants: a prospective clinical study of 1527 consecutively treated patients

OBJECTIVES: Various imaging techniques, including conventional radiography and computed tomography, are proposed to localize the mandibular canal prior to implant surgery. The aim of this study is to determine the incidence of altered mental nerve sensation after implant placement in the posterior segment of the mandible when a panoramic radiograph is the only preoperative imaging technique used. MATERIAL AND METHODS: The study included 1527 partially and totally edentulous patients who had consecutively received 2584 implants in the posterior segment of the mandible. Preoperative bone height was evaluated from the top of the alveolar crest to the superior border of the mandibular canal on a standard panoramic radiograph. A graduated implant scale from the implant manufacturer was used and 2 mm were subtracted as a safety margin to determine the length of the implant to be inserted. RESULTS: No permanent sensory disturbances of the inferior alveolar nerve were observed. There were two cases of postoperative paresthesia, representing 2/2584 (0.08%) of implants inserted in the posterior segment of the mandible or 2/1527 (0.13%) of patients. These sensory disturbances were minor, lasted for 3 and 6 weeks and resolved spontaneously. CONCLUSIONS: Panoramic examination can be considered a safe preoperative evaluation procedure for routine posterior mandibular implant placement. Panoramic radiography is a quick, simple, low-cost and low-dose presurgical diagnostic tool. When a safety margin of at least 2 mm above the mandibular canal is respected, panoramic radiography appears to be sufficient to evaluate available bone height prior to insertion of posterior mandibular implants; cross-sectional imaging techniques may not be necessary.     

Use of panoramic radiographs in general dental practice in England

The rapid growth in the use of panoramic radiographs provoked this survey of the reasons why general dental practitioners in Avon take such views. Of the 193 dentists who responded, 42 (22%) took one or more panoramic radiographs during a specified week. A total of 195 patients, 8% of those x-rayed, had a panoramic radiograph taken either alone or in combination with other views. Panoramic radiographs were stated to have been taken primarily for the diagnosis of caries (48%) and surgical (24%), periodontal (20%), orthodontic (20%) and endodontic/apical assessment. These findings are discussed with respect to published guidelines on the use of panoramic radiographs and the teaching of radiology in dental schools.     

锥形束CT与曲面断层在诊断下颌骨骨折中的比较研究

目的对比研究锥形束CT与曲面断层对下颌骨骨折的诊断特点及差异。方法收集2010年4月至2010年10月共27例因颌面部外伤行锥形束CT和曲面断层检查的患者的临床资料,比较两种方法对下颌骨不同部位骨折的诊断率。结果锥形束CT在下颌骨各部位的骨折诊断中均能明确观察骨折线及断端移位情况,而曲面断层存在漏诊现象,漏诊率为27.5%（11/40）,特别是髁突及颏部骨折,漏诊率分别为35.3%和27.3%。结论曲面断层检查存在漏诊的可能,特别是髁突或颏部骨折时,漏诊率更高。建议对下颌骨骨折应结合锥形束CT检查,以避免漏诊。同时,锥形束CT三维重建在帮助医生制定手术计划方面有很大优势和广泛应用前景。     

Radiological assessment of periapical status using the periapical index: comparison of periapical radiography and digital panoramic radiography

AIM: To compare the use of periapical radiographs and digital panoramic images displayed on monitor and glossy paper in the assessment of the periapical status of the teeth using the periapical index (PAI). METHODOLOGY: A total of 86 subjects were examined. All participants underwent a full-mouth radiographic survey (14 periapical radiographs) and a panoramic radiography. The periapical status, using the PAI score, of all appraised teeth was assessed. RESULTS: Periapical radiographs allowed the assessment of the periapical status of 87% of teeth using the PAI. On the contrary, digital radiography had a significantly reduced potential to allow assessment of the periapical status (P<0.01). Only 57.6% and 34.1% of teeth could be appraised using digital panoramic images displayed on monitor and glossy paper respectively (P<0.01). The total percentage of teeth with periapical pathosis was five fold higher when assessed with digital panoramic images displayed on glossy paper compared with periapical radiographs (P<0.01). CONCLUSIONS: Teeth were best viewed on periapical radiographs except maxillary second and third molars, which were better viewed in orthopantomograms. Orthopantomograms on screen were scorable more often than when on printed images. Apical periodontitis was scored more often on paper than on screen, and more often on screen than in periapical radiographs.     

Comparison of panoramic and standard radiographs for the diagnosis of mandibular fractures

This study was undertaken to compare the panoramic radiograph with the standard hospital mandibular series for the diagnosis of mandibular fractures. Of the 88 fractures present in the patient population, 92% were recognized in the panoramic radiograph, while only 66% were detected in the hospital series. All fractures seen in the hospital series were also seen in the panoramic view. It was therefore concluded that the panoramic view is superior to the standard hospital series for the diagnosis of mandibular fractures.     

Image-based diagnosis of condylar head fractures of the mandible: four case studies

This paper reports the four cases of the condylar head fractures of the mandible. The diagnostic images with panoramic radiograph and CT are presented. From 4 cases of condylar head fractures, the incidence, causes, and mechanisms are also discussed together with previous report.     

全颌曲面断层片预测下颌第三磨牙拔除致下颌角骨折风险的研究

目的：利用全颌曲面断层片预测下颌第三磨牙拔除致下颌角骨折的风险。方法：筛选2009年6月，2010年6月期间我科186张（共347颗下颌第三磨牙）全颌曲面断层片，计算下颌第三磨牙区剩余骨高度（b）与下颌骨高度（a）的比值（b／a值），分析该比值在人群中的分布情况。结合6例智齿拔除致下颌角骨折病例的b／a值，分析该比值用于预测下颌第三磨牙拔除术致下颌角骨折风险的临床意义。结果：347颗第三磨牙区b／a值符合正态分布，比值低于0．3的病例2例，占0．58％；分析文献中6例智齿拔除术致下颌角骨折病例b／a值均小于0．3，符合第三磨牙区b／a值的人群分布特征，属于小概率事件。结论：下颌第三磨牙拔除术后剩余骨高度与该区下颌骨高度的比值低于0．3者有较高下颌角骨折风险，全颌曲面断层片可以作为提示此风险的一种有效手段。