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颌窦的距离。结果当曲面体层片显示上颌窦的皮质骨连续,牙根距上颌窦存在明显距离、与上颌窦相切时,曲面体层片判断上颌后牙牙根与上颌窦关系的准确率分别为82.0%、70.0%;当曲面体层片显示上颌窦皮质骨中断,牙根突入上颌窦内时,曲面体层片判断上颌后牙牙根与上颌窦关系的准确率为48.5%。曲面体层片、锥形束CT均显示牙根突入上颌窦时,曲面体层片测量上颌后牙牙根突入上颌窦距离为(2.19±1.82)mm,而锥形束CT测量距离为(1.47±1.01)mm,两者差异具有统计学意义(P<0.05)。结论曲面体层片判断上颌后牙牙根未进入上颌窦的准确率较高,但判断上颌后牙牙根突入上颌窦的准确率较低。     

Combined Regenerative and Vital Pulp Therapies in an Immature Mandibular Molar: A Case Report

IntroductionThis report describes the treatment of an immature mandibular molar by combining vital pulp therapy (VPT) and regenerative endodontic procedures (REPs). It details the use of REP to regain functionality and continued root development of an immature root with pulp necrosis and VPT for an immature root containing vital pulpal tissues.MethodsAn 8-year old male presented for evaluation of a mandibular first right molar with mild buccal swelling and a nontraceable sinus tract. He recently had received a restoration. After intraoral and radiographic examination, a diagnosis of pulp necrosis and chronic apical abscess was made. After access, pulp necrosis was confirmed in the distal root; however, vital pulp tissues were present in the mesial canals. It was decided on pulpotomy (VPT) in the mesial and REP in the distal root. At the initial visit, pulpotomy was completed in the mesial root, and REP was initiated in the distal root. Three weeks later, the patient was asymptomatic and the sinus tract absent. REP was completed in the distal root, and the tooth was restored.ResultsAt the 6-, 12-, and 18-month follow-up, the patient presented without symptoms, and the tooth responded positively to pulp sensibility tests. Radiographic examinations showed resolution of the apical radiolucency and completed root development.ConclusionsCombined treatment using both VPT and REP for immature molars with different pulpal status in individual roots may be a preferable treatment option because preservation of vital pulp tissues and regeneration of new vital tissues allow for continued root development and functionality.     

Bone regeneration at the distal aspect of the adjacent second molar after lower third molar coronectomy: a long-term analysis

A residual bone defect at the distal aspect of the adjacent second molar may occur after total removal of the lower third molar. Lower third molar coronectomy has been proved to be a safe alternative to total removal, but the extent of bone regeneration at the adjacent tooth after coronectomy is not well reported. The aim of this prospective study was to investigate the long-term bone regeneration at the distal aspect of the adjacent second molar after lower third molar coronectomy. Preoperative and postoperative cone beam computed tomography scans were measured to assess bone regeneration at the distobuccal (DB), mid-distal (MD), and distolingual (DL) aspects of the lower second molar. Forty-eight coronectomies in 37 patients (23 female) with a mean ± standard deviation age of 29.1 ± 7.2 years were assessed. The mean follow-up was 93.2 ± 8.7 months. The mean bone level increase at DB, MD, and DL aspects was 3.2 ± 1.6 mm, 3.5 ± 1.5 mm, and 3.2 ± 1.6 mm, respectively; the bone levels were significantly higher than the preoperative measurements (P < 0.001). Age and impaction patterns were not factors affecting bone regeneration. Based on this study, it appears that coronectomy of the lower third molar brings favourable bone regeneration at the distal aspect of the adjacent second molar.     

Patient,radiological, and operative factors associated with surgical difficulty in the extraction of third molars: a systematic review

The aim of this systematic review was to determine the patient, radiological, and operative variables associated with surgical difficulty in the extraction of third molars, according to a visual analogue scale completed by the surgeon, operative time, or surgical technique. Searches of the PubMed (MEDLINE), Scopus, and Cochrane Library databases were conducted by two independent reviewers. Randomized and non-randomized clinical trials and prospective cohort studies evaluating surgical difficulty in the extraction of impacted mandibular or maxillary third molars according to patient, radiological, and operative variables were included. The full texts of 21 of the 859 articles initially retrieved were analysed, and 15 articles were included in the final systematic review. All 15 reported prospective cohort studies. The following variables were found to be on the spectrum of highly difficult or complex cases: older patient age and being overweight (patient variables), surgeons with little experience and the use of complex surgical techniques requiring tooth sectioning linked to hard tissue impaction (operative variables), and adverse radiological factors such as deep impaction, unfavourable angulation and root morphology, and a close relationship with the second molar, maxillary sinus, or the inferior alveolar nerve canal (radiological variables).     

基于CBCT的下颌第一磨牙区即刻种植相关的影像学研究

目的利用CBCT研究下颌第一磨牙区即刻种植适宜的植入位点、植入角度与植入深度,为术前数字化设计和临床操作提供参考依据。方法选取100例符合纳入标准的患者CBCT影像学资料,测量下颌第一磨牙区的牙槽骨厚度、颊侧及舌侧骨板厚度、牙根间隔宽度,同时测量下颌第一磨牙与下颌神经管及舌侧骨倒凹的关系,并进行统计学分析。结果由近中至远中,下颌第一磨牙的牙槽骨厚度及颊侧骨板厚度逐渐增大,舌侧骨板厚度逐渐减小;由牙槽嵴顶至根尖,牙根间隔宽度逐渐增大,最大为(5.00±1.42)mm;近中根、远中根、远舌根、牙根间隔顶至下颌神经管的距离分别为(7.47±2.38)mm、(7.19±2.49)mm、(9.59±1.94)mm、(15.90±2.39)mm;由近中至远中,下颌神经管颊侧及舌侧骨板最大厚度分别为(6.54±1.25)mm、(2.53±0.84)mm;下颌舌侧骨倒凹角度为(149.67±8.30)°,倒凹深度为(1.51±0.43)mm。结论在下颌第一磨牙区即刻种植前可通过CBCT规划合适的种植路径,注意避开下颌神经管和舌侧骨倒凹。若根尖至下颌神经管的安全距离足够,可从牙根间隔处植入,若安全距离不足,植入位点可偏近中舌侧,植入角度可适当舌倾。     

罹患重度牙周病变磨牙采取微创拔牙和微翻瓣位点保存术后种植修复效果观察（附1例3年随访报告）

种植治疗因其临床长期效果稳定,逐渐成为牙列缺损或缺失后的常规修复方法,而充足的骨量和良好的软组织条件对种植治疗方案的实施至关重要。罹患重度牙周病变的磨牙不但在拔牙之前已经存在牙槽骨吸收,而且在拔牙窝愈合过程中所发生的不同程度牙槽骨吸收均会增加种植治疗的难度。文章完整展示了1例磨牙牙周-牙髓联合病变病例从病情分析、采取微创拔牙和微翻瓣技术在拔牙窝实施位点保存创造良好硬组织条件、按照标准化流程完成种植修复到追踪观察3年的具体实施过程,为评价此类病例微创拔牙和微翻瓣位点保存术后种植修复的长期效果提供了依据。     

黏膜下注射曲马多对下颌智齿术后疼痛的疗效

目的：评估黏膜下注射曲马多缓解下颌智齿术后疼痛的有效性。方法：选取拔除智齿的患者40例,采用随机数字表法分成实验组（A组：曲马多注射组）和对照组（B组：生理盐水注射组）。采集患者在术后1、2、6、24、48 h由视觉模拟疼痛量表（VAPS）评定的分值。采用具有一个重复测量两因素一元定量资料方差分析统计。结果：A组术后疼痛评分显著降低,在2、6、24 h差异有统计学意义（P=0.006,P<0.001,P<0.001）。术后48 h无统计学意义（P=0.061）。结论：曲马多黏膜下注射对下颌第三磨牙术后早期疼痛控制有明显疗效。     

下颌第三磨牙萌出状态与第二磨牙远中邻面龋坏的相关性研究

目的:研究下颌第三磨牙萌出状态与第二磨牙远中邻面龋坏的相关性。方法 :临床收集因下颌第三磨牙不适而就诊的患者204例,运用锥形束CT分析下颌第二磨牙远中邻面龋坏与第三磨牙阻生类型(高位、中位、低位)、阻生角度以及两磨牙的釉牙骨质界距离(cementoenamel junction,CEJ)等因素是否存在相关性。结果:在下颌第三磨牙存在的情况下,第二磨牙远中邻面龋坏发生率高达78.4%;性别差异无统计学意义(P=0.165);高位、中位和低位阻生的龋坏发生率差异无统计学意义(P=0.646);而当第三磨近中阻生角度为40~80°时,第二磨牙远中邻面最易发生龋坏,与其他阻生角度组的差异有统计学意义(P<0.001);当第二磨牙与第三磨CEJ距离在6~9 mm时,第二磨牙远中邻面龋坏高于其他组,差异有统计学意义(P<0.001)。结论:下颌第三磨牙近中阻生角度、第三磨牙与第二磨牙的CEJ距离与第二磨牙远中邻面龋坏的发生密切相关。当第三磨近中阻生角度在40~80°间,且两磨牙间的CEJ距离在6~9 mm时,第二磨牙远中邻面更容易发生龋坏,此类阻生齿建议尽早拔除。