Substantial regional differences in the biomechanical behavior of molar treated with selective caries tissue removal technique: a finite element study

ObjectivesSelective caries removal (SCR) is recommended over non-selective removal for managing deep carious lesions to avoid pulp exposure and maintain pulp vitality. During SCR, residual carious dentin is left behind and sealed beneath the restoration. The biomechanical effects of such residual lesions on the restored tooth remain unclear and were assessed using finite element modeling (FEM).MethodsBased on μ-CT images of a healthy permanent human third molar, we developed five finite element models. Generic class I and II cavity restorations were modeled where residual lesions of variable sizes were either left or fully removed on occlusal and proximal surfaces. The cavities were restored with adhesive composite. All 3D-FE models were compared with a model of a healthy, non-treated molar. A vertical load of 100 N was applied onto the occlusal surface.ResultsRegardless of the lesion size, in molars with occlusal lesions higher mean stresses were predicted along the filling-lesion interface than in all other models. The smallest occlusal lesion (Ø₁ = 1 mm) resulted in the highest maximum stresses at the filling-lesion interface with large stress concentrations at the filling walls indicating failure risk. In conclusion, lesion site and extent are influencing parameters affecting the filling-lesion interactions and thus the biomechanical behavior of the tooth after SCR.SignificanceRetaining carious lesions around the pulpal floor affects the deformation and stress states in tooth-filling complexes. The higher stresses observed in molars with occlusal lesions may affect restoration stability and longevity. Suprisingly, more extended occlusal lesions may provide a more favorable tooth performance than less extended ones. In contrast, in molars with proximal lesions the residual lesion had only limited effect on the tooth’s biomechanical condition.     

A meta-analysis of the pros and cons of partial superficial parotidectomy versus superficial parotidectomy for the treatment of benign parotid neoplasms

ObjectivesSalivary gland tumors are predominantly benign and frequently localized in the parotid gland (P). The treatment consists primarily of surgical removal; however, the appropriate extent remains a subject of debate. In suitable tumors, superficial parotidectomy (SP) may be substituted for less invasive partial superficial parotidectomy (PSP) (I C). This systematic review analyzed the available literature, comparing PSP and SP with regards to several postoperative outcome parameters (O).Materials and methodsEstablished medical databanks were screened for articles evaluating outcomes of PSP compared with SP, published between 1955 and 2019. These data were assessed by pooled risk and odds ratios via meta-analysis.Results11 studies with 1272 patients were included. There was no significant difference in tumor recurrence between PSP and SP (primary outcome). Furthermore, no differences in the occurrence of permanent facial nerve paralysis (FNP), salivary fistula, great auricular nerve analgesia, or hematoma were observed between the groups. However, PSP displayed significantly reduced rates of transient FNP, Frey's syndrome, scar deformity, and xerostomia, as well as shorter surgical time, compared with SP (secondary outcomes).ConclusionBased on these data, PSP can be recommended as a surgical technique for the treatment of superficially located, small, benign parotid tumors.     

Fitting the Balding–Nichols model to forensic databases

Large forensic databases provide an opportunity to compare observed empirical rates of genotype matching with those expected under forensic genetic models. A number of researchers have taken advantage of this opportunity to validate some forensic genetic approaches, particularly to ensure that estimated rates of genotype matching between unrelated individuals are indeed slight overestimates of those observed. However, these studies have also revealed systematic error trends in genotype probability estimates. In this analysis, we investigate these error trends and show how they result from inappropriate implementation of the Balding–Nichols model in the context of database-wide matching. Specifically, we show that in addition to accounting for increased allelic matching between individuals with recent shared ancestry, studies must account for relatively decreased allelic matching between individuals with more ancient shared ancestry.     

Five-Years Trigger Finger Due to Partial Flexor Tendon Laceration in a Child

Trigger finger (TF) is a condition that affects quality of life and one of the most common causes of hand pain and disability. TF is characterized by catching, snapping or locking of the involved finger flexor tendon, associated with pain. TF in the children occurs rarely than in adults and partial tendon laceration is an uncommon cause of TF in the children. Thus, our aim in this study to define TF due to partial flexor tendon laceration in a child.

Electronic supplementary material

The online version of this article (doi:10.1007/s12593-015-0180-8) contains supplementary material, which is available to authorized users.     

部分脾栓塞术治疗外伤性脾破裂的临床应用

目的 探讨部分脾栓塞术(partial splenic embolization,PSE)治疗外伤性脾破裂的治疗效果.方法 回顾性分析2013年1月至2015年1月28例行开腹脾切除术治疗外伤性脾破裂病人的临床资料及同期开展的27例行PSE治疗外伤性脾破裂病人的临床资料并行对比分析.结果 行开腹脾切除术治疗组28例均痊愈.行PSE治疗组27例中,26例顺利完成选择性出血血管栓塞,其中1次栓塞成功25例,再次栓塞成功1例,无继发出血及开腹手术病例;1例栓塞过程中发现脾动脉主干受损,行脾动脉主干栓塞控制出血后立即中转开腹行手术处理;均痊愈出院.结论 PSE是治疗外伤性脾破裂的一种有效、微创的方法,且保留了脾脏功能.     

部分脾动脉栓塞治疗脾功能亢进的临床应用及进展

脾功能亢进(脾亢)是继发于肝硬化、门静脉高压的一种常见临床病症,传统的治疗方法中只有外科手术切除脾脏疗效明确。近年来部分性脾动脉栓塞术(PSAE)因其创伤小、风险低、疗效肯定等优势,已成为治疗脾亢的重要方法,且逐渐受到临床医师的认识和重视。该文通过对脾亢基础临床资料、临床介入治疗方法及疗效评价予以综述,针对脾亢的介入治疗现状及未来发展方向进行展望。     

白藜芦醇对部分肝切除术大鼠肝再生和肝组织NK细胞活性的影响*

目的 探讨白藜芦醇(RES)对肝部分切除大鼠肝组织自然杀伤(NK)细胞活性和肝再生的影响。方法 随机将90只SD大鼠分为对照组、小剂量白藜芦醇和大剂量白藜芦醇处理组,各组30只,分别经尾静脉注射生理盐水、白藜芦醇10 g.kg^-1·d^-1和20 g.kg^-1·d^-1,连续5 d,然后行70%肝脏切除术。检测肝脏再生指数,使用流式细胞术测定肝组织NK细胞百分率,采用⁵¹Cr释放法测定NK细胞杀伤活性,采用蛋白印迹法检测肝组织增殖细胞核抗原(PCNA)和CyclinD1蛋白表达。结果 在24 h和48 h,大剂量白藜芦醇处理组大鼠肝脏再生指数分别为(1.89±0.04)和(2.45±0.07),显著大于小剂量白藜芦醇处理组【(1.59±0.06)和(2.12±0.05),P<0.05】或对照组【(1.43±0.03)和(1.92±0.05),P<0.05】;大剂量白藜芦醇处理组大鼠NK细胞百分率分别为(24.62±1.36)%和(25.47±1.19)%,显著高于小剂量白藜芦醇处理组【(22.21±1.98)%和(22.36±1.78)%,P<0.05】或对照组【(17.36±1.78)%和(18.65±1.69)%,P<0.05】;大剂量白藜芦醇处理组大鼠NK细胞杀伤活力分别为(48.48±2.69)%和(49.01±2.78)%,显著高于小剂量白藜芦醇处理组【(41.88±2.65)%和(42.32±2.58)%,P<0.05】或对照组【(28.32±2.36)%和(30.12±2.36)%,P<0.05】;大剂量白藜芦醇处理组大鼠肝组织PCNA和CyclinD1蛋白相对表达量显著强于小剂量白藜芦醇处理组和对照组,差异有统计学意义(P<0.05)。结论 RES可以促进肝部分切除术大鼠肝再生,可能与增强了NK细胞活性和相关蛋白表达有关。