A comparative study of three different approaches to the comfortable zone

By means of a screw jack device, applied to thirteen edentulous subjects, the comfortable zone was approached in three different ways, by the central, the internal and the external approaches. Correspondingly, the zonal borders behaved differently. Applying the central approach it was found that the initial height of the screw jack had a lingering effect upon subsequent adjustments of the screw. Moreover, lower border data collected by the external approach distinguished themselves from other zonal border data by showing a significantly lower susceptibility to successive adjustments. The study suggests that muscle activity is a factor on which the perceptual mechanism relies, when a zonal border is assessed subjectively by a patient.     

Reliability of orbital volume measurements based on computed tomography segmentation: Validation of different algorithms in orbital trauma patients

PurposeTo compare the most common methods of segmentation for evaluation of the bony orbit in orbital trauma patients.Materials and methodsComputed tomography scans (before and after treatment) from 15 patients with unilateral blowout fractures and who underwent orbital reconstructions were randomly selected for this study. Orbital volume measurements, volume difference measurements, prolapsed soft tissue volumes, and bony defect areas were made using manual, semi-automated, and automated segmentation methods.ResultsVolume difference values between intact and damaged orbits after surgery using the manual mode were 0.5 ± 0.3 cm³, 0.5 ± 0.4 cm³ applying semi-automated method, and 0.76 ± 0.5 cm³, determined by automated segmentation (р = 0.216); the mean volumes (MVs) for prolapsed tissues were 3.0 ± 1.9 cm³, 3.0 ± 2.3 cm³, and 2.8 ± 3.9 cm³ (p = 0.152); and orbital wall defect areas were 4.7 ± 2.8 cm², 4.75 ± 3.1 cm², and 4.9 ± 3.3 cm² (p = 0.674), respectively.ConclusionsThe analyzed segmentation methods had the same accuracy in evaluation of volume differences between two orbits of the same patient, defect areas, and prolapsed soft tissue volumes but not in absolute values of the orbital volume due to the existing diversity in determination of anterior closing. The automated method is recommended for common clinical cases, as it is less time-consuming with high precision and reproducibility.     

Surgical timing in orbital fracture treatment: experience with 108 consecutive cases

Orbital fractures can lead to esthetic deformities and functional impairments, and adequate surgical timing is considered important in obtaining good results from surgery. By means of chart review, a retrospective analysis was carried out in 108 consecutive cases of pure orbital fractures to investigate the differences in surgical timing and the correlations with patient age and clinical and radiographic findings. In this analysis, surgical timing of pure orbital fractures was strongly related to the combination of parameters such as anatomical location of the fracture, eventual exposure of the fracture, cerebrospinal fluid (CSF) leakage or penetrating wounds, age of patients, eventual functional impairments or muscle entrapment, and serious conditions of compression or ischemia. As the data confirmed, an urgent approach was considered indispensable in severe orbital apex fractures and in orbital fractures with CSF leakage, penetrating objects, or exposure. Early surgery was necessary within 3 days in children with diplopia (type IIIb) and mainly within 7 days in adults with double vision (type IIIa). Delayed surgery, within 12 days in all cases, was performed orbital wall fractures with no impairments (type II) or in orbital rim fractures (type I). Data from this retrospective analysis confirm the need for an aggressive approach to all orbital fractures. In our experience, surgery was performed within 12 days and most orbital fractures were treated during the first week after trauma, which is earlier than previously reported.     

A comparative study between transbuccal and extra-oral approaches in treatment of mandibular fractures

Background and objectives  

Mandibular angle fractures continue to be a common type of facial injury. The objectives in treatment are to effect rapid healing by anatomic reduction and fixation and to restore function and appearance with minimal disability and complications.     

Technical considerations of computer-aided planning in severe orbital trauma: A retrospective study

The aim of this study was to evaluate the clinical outcomes of linear and orbital volume measurements in severe orbital trauma. Patients with severe orbital trauma that involved more than two walls and entailed a marked degree of comminution were included in this retrospective analysis. However, patients with incomplete clinical records and a simple blowout or zygmatico-orbital fractures were excluded. All the cases underwent surgical correction guided by virtual surgical planning and 3D-printed templates. The measurement protocol depended on assessing orbital dimensions, orbital volumetry, and the zygomatic bone's position in the three-dimensional planes. All patients' preoperative 3D CT scans were obtained, and DICOM files were imported into a three-dimensional image processing software. Data were then converted for 3D reconstruction in the axial, coronal, and sagittal views. A total of 18 patients with a mean age was 39.28 ± 6.28 were included in this study. The results revealed a significant difference between the pre and postoperative differences in distances in relation to the FHP (Frankfurt Horizontal Plane) (P = 0.0014) and sagittal planes (P < 0.0001). The orbital width and height of the traumatized orbit were significantly decreased from 45.26 ± 6.72 mm and 45.30 ± 2.89 mm to 39.74 ± 3.91 mm (P = 0.0022), and 40.34 ± 0.86 mm (P < 0.0001), respectively. Clinically, there was a satisfactory degree of symmetry regarding the zygomatic bones' position and orbital dimensions postoperatively. Moreover, the mean orbital volume on the traumatized side decreased significantly from 23.16 ± 1.91 cm³ preoperatively to 20.7 ± 1.96 cm³ postoperatively (P < 0.0001). These findings were associated with a low incidence of complications. Within the limitations of the study it seems that the described methodology is a relevant addition to clinical treatment options. It incorporates all the latest technology to plan virtual reconstruction surgery in the treatment of complex orbital trauma and should be adapted accordingly in cases of severe displacement and comminution.     

Diagnosis and treatment of retrobulbar haematomas following blunt orbital trauma: a description of eight cases

Retrobulbar haematoma following blunt orbital trauma is a rare, but potentially serious, complication, since it can evolve rapidly from visual impairment to permanent loss of vision. This sight-threatening situation most commonly arises from orbital bleeding accompanying undisplaced fractures of the orbital walls, an event that increases the pressure inside the orbit and results in vascular damage to the optic nerve. The clinical presentation includes pain, exophthalmos with proptosis, and internal ophthalmoplegia, with impairment or loss of the pupillary reflex. A thin-layer orbital CT scan is an essential diagnostic aid. Any delay between the onset of symptoms and treatment can have a significant effect on functional recovery. Therapy is based on orbital decompression, via different surgical approaches, with the intention of reducing the pressure on the nerve and vascular structures inside the orbit. This paper presents eight cases of retrobulbar haematoma and their follow-up, in detail.     

四种治疗牙本质过敏方法的临床效果研究

目的 通过使用极固宁(A组)、75%氟化钠甘油 (B组)、50%麝香草酚溶液(C组)和自酸蚀粘接剂(D组)治疗牙本质过敏症,观察脱敏疗效.方法 将128例患者中诊断牙本质过敏的240颗牙随机分为 A、B、C、D 4组, 分别用4种脱敏方法治疗1疗程, 即刻及3个月后观察比较疗效.结果 A组即刻及3个月后脱敏有效率均显著优于 B、C、D组 (P＜0.01). 结论 极固宁为相对快速,有效的牙本质脱敏剂.     

A comparative evaluation of different treatment modalities for parasymphysis fractures: a pilot study

Maxime Champy advised the use of two miniplates for parasymphysis fractures because of the high torsional forces in the anterior region of the mandible. According to him there is no need for intraoperative or postoperative intermaxillary fixation, but most surgeons use arch bars for intraoperative or postoperative intermaxillary fixation. This study evaluated the role of the lower arch bar as a tension band eliminating the need for an upper miniplate (tension band plate) in cases of parasymphysis fractures. 3 groups underwent treatment. In the first group, two titanium miniplates were placed across the fracture site along with Erich's arch bar for 6 weeks. In the second group, two titanium miniplates were used for osteosynthesis without Erich's arch bar. In the third group, one titanium miniplate was placed along with Erich's arch bar for 6 weeks. The results of third group were statistically non-significant compared with those of the first and second groups.     

A comparison of imaging techniques with surgical experience in orbital injuries: A prospective study

The aim of the study is to compare the effectiveness of computerised tomography (CT) and magnetic resonance (MR) imaging in diagnosing herniation and entrapment of orbital soft tissues in orbital fractures. 15 consecutive patients with clinical signs and symptoms of medial orbital wall injury were examined with CT and MR. The data were subsequently compared with the findings of the surgical exploration with regard to the extent of the wall fractures, the presence of soft tissue herniation and its entrapment. CT and MR were equally accurate in demonstrating or excluding orbital wall fractures but both modalities slightly underestimated their incidence. CT and MR underestimated the actual incidence of soft tissue herniation and entrapment when compared with the surgical findings but the extent of soft tissue herniation and entrapment were demonstrated more clearly by MR than by CT scanning. MR imaging when available should therefore be used as the initial imaging modality and CT held in reserve for confirmation as positioning in the MR unit is easier and more comfortable for recently injured patients who may well have other injuries.     

A comparative study of maxillo-facial trauma in Bristol and Bordeaux

Consecutive patients with maxillofacial fractures who attended departments of maxillofacial surgery in Bristol and Bordeaux during 1985-1986 were surveyed prospectively to determine differences in demography and aetiology and patterns of injury. 1,652 patients were included: 1,146 in Bordeaux and 506 in Bristol. Significantly more patients with nasal complex fractures were treated in Bordeaux reflecting management of these injuries by oto-rhino-laryngologists in Bristol. Maxillary fractures were comparatively more frequent in Bordeaux, reflecting a higher incidence of road accidents. Significantly more assault victims were treated by maxillofacial surgeons in Bristol, though per capita alcohol consumption by age and sex matched individuals was greater in France than in the U.K. Incidence of fracture was 18/100,000 hospital catchment population/year in Bordeaux, compared to 32/100,000 population/year in Bristol; reflecting that in contrast to Bristol, specialists in private practice outside the regional centre treated patients with fractures in S. W. France. Differences in aetiology of injury could be explained by cultural factors. Formal twinning arrangements and EEC membership provide excellent opportunities for postgraduate education, training and collaborative clinical research.     

20例颅颌面部为主的多发伤救治体会

目的 探讨颅颌面部为主多发伤的救治策略。方法 回顾分析2013年3月—2018年3月间收治的20例颅颌面部为主多发伤患者（男16例,女4例;年龄9~83岁,平均40.8岁）的救治情况,包括早期急救、组织器官损伤、损伤控制性手术开展、功能恢复或重建、创面愈合以及预后情况。结果 20例患者中,初级生命支持情况分别为急诊清创止血19例,单纯液体复苏13例,大量液体复苏+输血4例,气管插管或切开5例,外固定（石膏或骨牵引）4例。损伤情况分别为2处损伤3例,3处损伤4例,4处损伤7例,损伤5处及以上6例。损害控制性手术开展情况分别为损伤控制性手术10例,其中,眼球探查修补1例,颅内血肿清除及去骨瓣减压1例,剖胸探查止血+肺裂伤缝合+胸腔闭式引流1例,介入止血1例,骨牵引外固定2例,创面修复（清创后负压封闭创面）4例。EICU继续高级生命支持情况分别为6例患者在抢救室经初级生命支持后,生命体征稳定而直接转入专科,做确定性手术治疗;14例患者由抢救室转入EICU继续高级生命支持,其中10例病情稳定后联合专科行早期确定性手术,4例病情严重无法早期确定性手术患者伤情稳定后直接出院,后续行整形或功能重建。20例患者全部存活,无死亡。结论 实现急诊急救一体化,早期器官功能支持,是颅颌面部严重创伤成功救治的重要策略之一。     

创伤性颞下颌关节强直不同手术方法的比较研究

目的 探讨创伤性颞下颌关节强直伴内侧髁突残存的不同手术方法及疗效.方法 遵义医学院附属口腔医院2008年～2013年收治的创伤性颞下颌关节强直伴内侧髁突残存的患者18例,其中10例行关节间隙成形+喙突游离移植+颞肌筋膜瓣治疗,8例行外侧成形+颞肌筋膜瓣治疗.通过临床及CBCT随访比较两种方法的临床治疗效果,对术后复发率、咬合、面型的影响以及最大开口度变化进行统计学分析.结果 术后随访12～24月,关节间隙成形+喙突游离移植+颞肌筋膜瓣组术后复发患者2例(2/10),外侧成形术+颞肌筋膜瓣组术后无复发病例.外侧成形术+颞肌筋膜瓣组术后患者咬合、面型及最大开口度与关节间隙成形+喙突游离移植+颞肌筋膜瓣组比较有显著性差异(P＜0.05).结论 在内侧残存的髁突及关节盘可保留的情况下,采用外侧成形术+颞肌筋膜瓣是治疗创伤性颞下颌关节强直的理想术式.     

Influence of different treatment approaches on non-submerged and submerged healing of ligature induced peri-implantitis lesions: an experimental study in dogs

OBJECTIVE: [corrected] The aim of the present study was to evaluate non-submerged and submerged healing of ligature induced peri-implantitis in dogs. MATERIAL AND METHODS: Peri-implantitis was induced by ligature placement in five beagle dogs (n = 30 implants). The defects were randomly and equally allocated in a split-mouth design to either closed treatment + non-submerged healing (CNS), or open treatment + submerged healing (OS) using an Er:YAG laser (ERL), an ultrasonic device (VUS), or plastic curettes + local application of metronidazole gel (PCM), respectively. The animals were sacrificed after 3 months. Clinical, radiological and histological (e.g. new bone-to-implant contact (BIC)) parameters were assessed. RESULTS: All treatment procedures resulted in statistically significant improvements of all clinical parameters at both CNS and OS implants. Radiological improvements were merely observed at OS implants. Histomorphometrical analysis revealed that all CNS implants exhibited comparable low amounts of new BIC (1.0-1.2%), while mean BIC was statistically significant higher in the respective OS groups [ERL (44.8%), PCM (14.8%), VUS (8.7%)]. CONCLUSION: Within the limits of the present study, it was concluded that (i) OS improved the outcome of treatment in comparison with CNS and (ii) ERL seemed to be more suitable to promote re-osseointegration than PCM and VUS.     

Clinical application of automated virtual orbital reconstruction for orbital fracture management with patient-specific implants: A prospective comparative study

The aim of the study was to compare automated and manually conducted (slice-by-slice) virtual orbital wall reconstruction in terms of PSI design, manufacture, and clinical application for orbital fracture management.Patients with orbital wall fractures were evaluated for the potential for treatment with PSI, based on automated virtual wall reconstruction; these formed the main group. The surgical outcomes of these main-group patients' treatments were compared with those of the control group, which comprised patients randomly selected for this study, each of whom had the same orbital trauma patterns and were also managed with PSI. However, the control group patients were treated using ‘slice-by-slice’ virtual orbital reconstruction.Mean volume differences between the intact and reconstructed orbit were 0.65 ± 0.26 cm³ in the main group (n = 23) and 0.57 ± 0.23 cm³ in the control (n = 27; p = 0.837). In both groups, no cases of implant malposition or enophthalmos were detected after surgery. Orbital shape difference was similar for the main group and the control, at ?3.3 ± 3.5% and 3.25 ± 2.5%, respectively (p = 0.929). Diplopia was diagnosed at the 3-month follow-up in 13.0% of the main group and in 11.1% of the control (p = 0.651). The average times spent on computer-aided design (CAD) procedures, including segmentation, virtual orbital reconstruction, and PSI design, were 36.7 ± 6.9 min in the main group and 72.9 ± 7.7 min in the control group (p < 0.001).Within the limitations of the study it seems that PSI based on automated virtual reconstruction is a relevant alternative treatment option for orbital fractures because of its clinical efficacy that is similar to PSI based on a ‘slice-by-slice’ CAD protocol.     

A comparative scalability study of different retrofitting materials

The purpose of this study was to compare the sealing ability of high-copper amalgam, glass ionomer cement, and silver glass ionomer cement as retrofitting materials when used with and without varnish. Seventy extracted human single-rooted anterior teeth were instrumented and the root canals obturated with laterally condensed gutta-percha and sealer. The apical 3 mm of each root was resected and a 2 mm-deep apical Class I preparation cut. The roots were then randomly allocated to six groups of 10 teeth and retrofitled with one of die experiment materials. Group I comprised high-copper amalgam; group 2, high-copper amalgam with cavity varnish; group 3, glass ionomer cement without varnish: group 4, glass ionomer cement with varnish; group 5, silver glass ionomer cement without varnish; and group 6, silver glass ionomer cement with varnish. Two groups of five roots each were used as positive and negative controls. The root surfaces were coated with nail polish and specimens immersed in 2% methylene blue solution for 14 days. After vertical sectioning, dye penetration was examined under a stereomicroscope. The results of the study were analysed statistically. The sealing ability of the conventional glass ionomer cement with varnish was significantly better while dye penetration was higher in silver glass ionomer cement without varnish group than the other groups (P > 0.01).     

不同材料诱导犬根尖形成的比较研究

目的 比较羟磷灰石（HA）、氢氧化钙（CH）、Vitapex诱导犬年轻恒牙根尖形成的效果。方法 选用2只5~6月龄犬的16颗恒切牙,去髓后随机分为4组。A、B、C组为实验组,依次用HA、CH及Vitapex糊剂充填根管;D组为对照组,用AH plus糊剂充填。采用锥形束CT（CBCT）测量牙根长度及根尖面积的变化;制作石蜡切片行苏木精-伊红（HE）染色,观察根尖组织形态;制作冰冻切片行碱性磷酸酶（ALP）染色,观察细胞的成骨活性。结果 1）CBCT结果显示：术后4周,各组牙根均较术前延长（P<0.05）,3个实验组的根尖面积较术前缩小（P<0.05）;术后8周,各组根尖均显示高密度闭合影像。2）组织切片显示：各组根尖均无炎症反应;术后4周,根尖均未闭合,但有牙骨质及牙周膜伸入根管;术后8周,A组根尖被完整的牙骨质屏障封闭,ALP阳性细胞分布集中,B、C组牙骨质屏障内有间隙,牙周膜伸入其中,ALP阳性细胞散在分布,D组根尖仍有稀疏牙骨质和类牙骨质沉积,并有纤维及血管组织增生,ALP阳性细胞不明显。结论 经去髓后的年轻恒牙在无感染时牙根能继续发育,牙周膜可能是其发育的组织来源;HA诱导根尖形成的速度较快,是一种理想的根尖诱导材料。     

不同龋敏感儿童口腔不同基因型变异链球菌临床分离株在不同pH条件下产生GTF能力的比较研究

目的:探讨不同龋敏感儿童口腔变异链球菌不同基因型菌株在不同pH条件下产生GTF的能力.方法:从不同龋敏感儿童口腔变异链球菌中选取66株临床分离株,常规复苏、增菌并配制相同密度的菌悬液后,接种于不同pH值(以0.5为间隔,pH 5.0～7.0)的含2.5 g/L葡萄糖和0.05％ Tween 80的TYC培养基中厌氧培养18h;采用Somogyi法测定还原糖含量,计算酶活性.结果:在同一pH条件下,不同龋敏感儿童口腔变链菌GTF活性的差异具有统计学意义(P＜0.05),龋敏感性越高,GTF活性越大;同一龋敏感儿童口腔变链菌不同基因型菌株GTF活性的差异也具有统计学意义(P＜0.05),GTF活性随基因型的增加而增加;当pH5.5时,高龋、中龋儿童携带一种基因型菌株GTF活性显著下降(P＜0.05).结论:不同龋敏感儿童口腔变异链球菌不同基因型菌株在不同pH条件下GTF活性不同,携带基因型越多的菌株GTF活性越高.