Impacted Lower Third Molar Fused with a Supernumerary Tooth—Diagnosis and Treatment Planning Using Cone-Beam Computed Tomography

This paper reported a case of fusion between an impacted third molar and a supernumerary tooth, in which a surgical intervention was carried out, with the objective of removing the dental elements. The panoramic radiography was complemented by the Donovan＇s radiographic technique; but because of the proximity of the dental element to the mandibular ramus, it was not possible to have a final fusion diagnosis. Hence, the Cone-Beam Computed Tomography--which provides precise three- dimensional information--was used to determinate the fusion diagnosis and also to help in the surgical planning. In this case report we observed that the periapical, occlusal and panoramic were not able to show details which could only be examined through the cone-beam computed tomo- graphy.

Parental Knowledge of Pre-Hospital Management of Avulsed Permanent Tooth in Children at Kath

BACKGROUND: Permanent tooth avulsion is one of the severe forms of dental traumatic injuries. The immediate action taken at the site of the accident is crucial to the prognosis of the tooth. Replantation is considered as the treatment of choice. OBJECTIVE: The study was undertaken to assess the knowledge of parents who accompany their children to the pediatric dental clinic, KATH on the pre-hospital management of avulsed permanent tooth in children. METHODS: A researcher administered structured questionnaire was used to collect data on the knowledge of pre-hospital management of avulsed permanent tooth from 83 parents who accompanied their wards to the pediatric dental clinic at KATH. RESULTS: A total of 83 parents were involved in the study. 30 (36%) were males while 53 (64%) were females. The majority of the parents (57%) were either university trained or had attended college of education. Only 32 parents (39%) were aware of the possibility of replantation. Majority of the parents chose non-physiologic media as the transport media of choice and only 10% would attempt self-replantation before seeking professional help. 76 parents (92%) had no previous education on pre-hospital management of avulsed tooth. CONCLUSION: The results obtained from this study indicate that parental knowledge on pre-hospital management of avulsed permanent tooth is low hence the need for massive public educational campaigns.

Breast Cancer in a Supernumerary Breast at the Yaoundé Gynaeco-Obstetric and Paediatric Hospital: About a Case

Accessory or ectopic breast tissue is an anomaly in the development of the breast. It is a rare condition that occurs along the embryological mammary line. In less than 1% of all breast cancers, supernumerary breast cancer is reported, with the axillary location being the most common in 60% to 90% of cases. Cancerous degeneration of this supernumerary breast tissue can pose a dual diagnostic and therapeutic problem. We report the case of locally advanced adenocarcinoma in a right supernumerary breast. This is a 75-year-old, grand-multiparous, postmenopausal, and known hypertensive patient on treatment. Family history was remarkable for brain cancer in her sister and oesophageal cancer in her mother. She consulted for a mass in the right axillary cavity on supernumerary breast evolving for a year. Clinical examination revealed a large, fixed, budding and haemorrhagic-ulcerated mass of the right axilla, with long axis measuring about 15 cm. There was as wella supernumerary breast on the left, but without particularity. A soft tissue ultrasound showed a large hypoechoicmass in the right axillary region of 116 mm with areas of central necrobiosis. Morphologically, the breasts were normal. A breast MRI revealed a subcutaneous mass in the right axillary cavity with skin ulceration and satellite lymphadenopathy. The extension assessment revealed liver metastases, and a biopsy of the mass revealed a breast adenocarcinoma. The case was the subject of a multidisciplinary consultation meeting following which a wide excision of the mass was indicated. The histo-pathology analysis results of the surgical specimen were in favour of a triple negative papillary adenocarcinoma. After a post-operative multidisciplinary consultation meeting, adjuvant chemotherapy was indicated. The development of supernumerary breasts depends on hormones, just like normal breasts. Breast cancer in accessory breast tissue is quite rare with the incidence being 6%. The most common pathology is invasive carcinoma (50% - 75%). It is usually located in the armpit (60% - 70%) although it can be present in other less common locations such as the inframammary region (5% - 10%) and rarely the thighs, perineum, groin and the vulva. Since accessory axillary breast tissue is not considered during breast screening examination, it is necessary for clinicians to be aware of this entity and associated pathologies. Their preventive excision in women at high risk can also be considered.

A Case of Vasovagal Syncope Induced by Tooth Extraction

Background: Vasovagal syncope (VVS) is a neurogenic reflex-mediated fainting episode characterized by sudden, transient, and self-limiting symptoms. While VVS accounts for a significant portion (around 60%) of emergent medical events in dental practice, it remains an underrecognized condition among dental professionals, often misdiagnosed as hypoglycemia, conversion disorder, or epilepsy. This case report describes a VVS episode induced by tooth extraction, aiming to improve dental clinicians’ awareness and diagnostic approach to VVS. Case Presentation: A 35-year-old female visited the dental department in April 2022 with a two-year history of food impaction in the upper right molar. Examination revealed an elongated, discolored, and tender tooth 18, lacking proper occlusion with the opposing tooth. After confirming no contraindications, the tooth was extracted using a minimally invasive technique. Following the procedure, the patient experienced dizziness upon standing;her blood pressure was 69/47 mmHg, and her heart rate was 65 bpm. The nursing staff assisted her to sit as she showed limb weakness, closed eyes, and briefly lost consciousness. Oxygen was administered, and her blood glucose was 6.5. Blood pressure later improved to 124/78 mmHg, with a pulse of 62 bpm. Oral glucose was given, which she vomited, and emergency services were called. Upon arrival, the patient was alert and cooperative. Neurology consultation and imaging (MRI, MRA, and DWI) ruled out cerebral infarction, initially diagnosing a conversion disorder. A subsequent tilt-table test, including sublingual nitroglycerin, induced a marked blood pressure drop and symptoms confirming a diagnosis of vasovagal syncope (VVS). Conclusions: This case shows that preoperative anxiety, fear, and prolonged waiting can trigger vasovagal reflex during tooth extraction, especially in patients with anxiety or cardiac arrhythmias. For such patients, preoperative precautions and intraoperative cardiac monitoring are advised. In cases of VVS, quick actions like monitoring blood pressure, placing the patient in a supine position, providing oxygen, and administering IV fluids or medications like atropine, if necessary, can help stabilize the patient.

High-resolution CT-scan data reveals the tooth replacement pattern of the Late Jurassic tyrannosauroid Guanlong wucaii (Dinosauria, Theropoda)

The Tyrannosauridae,which is characterized by specialized pachydont dentition and putative bone-cracking predatory strategies,is one of the most extensively studied theropod lineages.Although tooth replacement patterns,crucial for understanding feeding behaviors,have been thoroughly studied in this group,studies on non-tyrannosaurid tyrannosauroids are relatively scarce.This study utilizes high-resolution CT data to investigate the tooth replacement pattern in two specimens of Guanlong wucaii,a Late Jurassic tyrannosauroid,and provides insights into the evolution of tooth replacement across Tyrannosauroidea.Second-generation replacement teeth,a rarity observed mainly in giant predatory theropods(e.g.some tyrannosaurids),were detected in the dentary dentition of the juvenile Guanlong.Zahnreihen reconstructions display a consistent cephalad alternating tooth replacement pattern in the maxilla and the dentary of both of the examined individuals,with Z-spacing values exceeding 2.0.As Guanlong grows,the Z-spacing value in the maxillary dentition increases,resembling the ontogenetic changes documented in the Tyrannosauridae.Additionally,like Tarbosaurus,Guanlong also displays a discontinuity between the tooth replacement waves at the premaxilla-maxilla boundary.This study thus demonstrates that some tyrannosaurid-like tooth replacement patterns were acquired before the origin of the Tyrannosauridae.

Association between Tooth Loss and Hypertension: A Systematic Review

Background: An independent relationship between tooth loss and hypertension appears to exist. Objectives: The aim of this study was to systematically review the relationship between tooth loss/number of teeth and hypertension. Materials and Methods: This review was conducted based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Guidelines. We searched all the relevant studies in international databases of PubMed and Google Scholar search engines from January 2000 to December 2023. Results: Fourteen studies (11 cross sectionals, 2 descriptives and 1 Cohort) met the inclusion criteria for this review. Most cross-sectional studies showed that participants with more tooth loss exhibited a greater proportion of hypertension and higher systolic blood pressure than those with less tooth loss. Cohort study showed that the loss of 8 or more teeth was associated with a higher risk of developing hypertension. Descriptive studies reported that missing teeth were marginally significantly associated with hypertension. Conclusion: This study has revealed a significantly higher SBP in patients with fewer remaining teeth or more tooth loss. In addition, those with more tooth loss showed a higher risk of hypertension than those with less tooth loss.

Single Tooth Segmentation on Panoramic X-Rays Using End-to-End Deep Neural Networks

In dentistry, panoramic X-ray images are extensively used by dentists for tooth structure analysis and disease diagnosis. However, the manual analysis of these images is time-consuming and prone to misdiagnosis or overlooked. While deep learning techniques have been employed to segment teeth in panoramic X-ray images, accurate segmentation of individual teeth remains an underexplored area. In this study, we propose an end-to-end deep learning method that effectively addresses this challenge by employing an improved combinatorial loss function to separate the boundaries of adjacent teeth, enabling precise segmentation of individual teeth in panoramic X-ray images. We validate the feasibility of our approach using a challenging dataset. By training our segmentation network on 115 panoramic X-ray images, we achieve an intersection over union (IoU) of 86.56% for tooth segmentation and an accuracy of 65.52% in tooth counting on 87 test set images. Experimental results demonstrate the significant improvement of our proposed method in single tooth segmentation compared to existing methods.

Effect of different interventions on orthodontic tooth movement acceleration:A network meta-analysis

Objective: To explore the effectiveness of various interventions in accelerating tooth movement, a systematic review and net-work meta analysis were used to draw a conclusion. Methods: MEDLINE, EMBASE, Willey Library, EBSCO, Web of Science Databases, and Cochrane Central Register of Controlled Trials databases to identify relevant studies. ADDIS 1.16.6 and Stata 16.0 software were used for NMA. Results: Five thousand five hundred and forty-two articles were searched out. After screening by two independent investigators, forty-seven randomized controlled trials, 1 390 participants, were included in this network meta-analysis. A total of 11 interventions involving Piezocision (Piezo), Photobiomodulation therapy (PBMT), Plate- let-rich plasma(PRP), Electromagnetic field(EF), Low intensity laser therapy(LLLT), Low intensity pulsed ultrasound(LI-PUS), Low-frequency vibrations(LFV), Distraction osteogenesis(DAD), Corticotomy(Corti), Microosteoperforations (MOPS), Traditional orthodontic(OT)were identified and classified into 3 classes including surgical treatment, non-surgical treatment and traditional orthodontic treatment. According to SUCRA probability ranking of the best intervention effect, when orthodontic treatment lasted for 1 month, PBMT (90.6%), Piezo(87.4%) and MOPs(73.6%)were the top three interventions to improve the efficiency of canine tooth movement. When orthodontic treatment lasted for 2 months, Corti (75.7%), Piezo (69.6%) and LFV(58.9%)were the top three interventions for improving the mobility efficiency of canine tooth movement. When orthodontic treatment lasted for 3 months, Cort (73.3%), LLLT(68.4%)and LFV(60.8%)were the top three interventions for improving the mobility efficiency of canine tooth movement. Conclusion: PBMT and Piezo can improve the efficiency of canine tooth movement significantly after 1 month, while Corti and LFV can improve the efficiency of canine tooth movement better after 2 and 3 months.

Charcot-Marie-Tooth病的遗传、临床和电生理观察(附20例临床分析)

本文报道 ２０例 Ｃｈａｒｃｏｔ－Ｍａｒｉｅ－Ｔｏｏｔｈ病的遗传、临床和电生理资料。其中男 １６例，女 ４例，平均发病年龄为２６．７５岁。发现４例显性遗传，３例隐性遗传，１０例散发，３例遗传情况不详。主要症状有高弓足、垂足、鹤腿和腱反射消失；上肢前臂有肌萎缩者占１／４。所有病人电生理检查均有失神经现象，特别是ＭＣＶ有明显减慢。且发现ＭＣＶ的减慢和临床严重程度无相关联系。

Effect of transcranial direct current stimulation on supernumerary phantom limb pain in spinal cord injured patient:A case report

BACKGROUND Supernumerary phantom limb(SPL)sensation is the experience of additional limbs,either single or a pair of limbs.Unique to traumatic spinal cord injuries,we report effect of transcranial direct current stimulation(tDCS)on SPL pain in a patient with cervical cord injury.CASE SUMMARY The subject was a 57-year-old man who was diagnosed with complete spinal cord injury(C6/C5,motor level;C5/C5,sensory level;AIS-A)approximately three months ago.After a period of 2 wk,we administered anodal tDCS over the motor cortex for 15 minutes at an intensity of 1.5 mA.Following that treatment,the patient experienced a decrease of SPL pain intensity and frequency,which lasted for 1 week after the end of treatment.CONCLUSION Targeting the motor cortex through neuromodulation appears to be a promising option for the management of SPL pain.

Pinion Tooth Surface Generation Strategy of Spiral Bevel Gears

Aviation spiral bevel gears are often generated by spiral generated modified（SGM） roll method.In this style,pinion tooth surface modified generation strategy has an important influence on the meshing and contact performances.For the optimal contact pattern and transmission error function,local synthesis is applied to obtain the machine-tool settings of pinion.For digitized machine,four tooth surface generation styles of pinion are proposed.For every style,tooth contact analysis（TCA） is applied to obtain contact pattern and transmission error function.For the difference between TCA transmission error function and design objective curve,the degree of symmetry and agreement are defined and the corresponding sub-objective functions are established.Linear weighted combination method is applied to get an equivalent objective function to evaluate the shape of transmission error function.The computer programs for the process above are developed to analyze the meshing performances of the four pinion tooth surface generation styles for a pair of aviation spiral bevel gears with 38/43 teeth numbers.The four analytical results are compared with each other and show that the incomplete modified roll is optimal for this gear pair.This study is an expansion to generation strategy of spiral bevel gears,and offers new alternatives to computer numerical control（CNC） manufacture of spiral bevel gears.

人体词“牙/齿”和“tooth”语义转移的认知研究

人体词"牙/齿",对应的英文词"tooth",基本义指称人体重要的部位之一。在漫长的语言演变过程中,主要借助隐喻和转喻的作用下,构成了一个连续统一的语义转移系统——基于突显和邻近原则的转喻所指:"年龄、口味、言语、情感";基于形貌相似的隐喻所指:"齿状物";基于隐喻转喻互动的隐转喻所指:"战争"。这说明了英汉民族某些共同的身体体验决定了认知的相通性。同时,在英汉民族思维中牙齿的言语交际功能都占有很突显的地位,汉民族还注重牙齿的外貌特征。

A Clinical Analysis of Tooth Size Discrepancy (Bolton Index) among Orthodontic Patients in Wuhan of Central China

The purpose of this study was to determine the total Bolton index （TBI） and anterior Bolton index （ABI）, evaluate the clinical significance of tooth size discrepancies and the influence of gender variation of mesiodistal tooth width on Bolton Index and estimate which tooth has the greatest influence on Bolton Index. A total of 110 pairs of pretreatment dental study casts （41 male and 69 female） were selected from patients treated in Department of Orthodontics of Union Hospital in Wuhan, China. A sliding dental Vernier caliper was used for the measurement of the mesiodistal tooth width. Descriptive statistical mean values, standard deviation, standard error of the mean values, coefficient of variance and the t-test were used for the statistical analysis of the data. The study found that TBI, ABI and the total sum of teeth width had no significant difference between male and female. Male group indicated that Bolton Index （BI） was mostly influenced by the width of lower right second premolar, whereas female group showed that BI was mostly influenced by the width of both the right and left maxillary lateral incisor.

剔除小鼠神经微管运动蛋白Kif1b基因导致类似Charcot-Marie-Tooth病动物模型

目的研究杂合子小鼠Kiflb基因剔除后导致的表现型,探讨其作为类似Charcot-Marie-Tooth (CMT)病动物模型的可行性。方法用Southern blotting和PCR检测同源重组和基因型,Western blotting测定杂合子KIF1B蛋白表达量,行为学实验观察其表现型。结果杂合子Kif1b基因剔除小鼠的KIF1B蛋白表达量减少了一半以上,行为学实验结果表明,杂合子基因剔除小鼠在运动和感觉方面均有异常。Rota-rod实验,Rod walking实验和Wire hanging实验中,野生型小鼠的停留时间均明显长于Kif1b基因剔除小鼠。同时,杂合子Kif1b基因剔除小鼠在热板实验和福尔马林实验中,表现出对温度觉和痛觉反应的迟钝,其反应时间与野生型小鼠相比明显延长,反应强度降低。结论杂合子Kif1b基因剔除小鼠的表现型与人类腓骨肌萎缩症相似,作为疾病模型具备可行性。

Analysis of the Stress Distribution Pattern of Anatomic and Non-Anatomic Tooth Forms on Maxillary and Mandibular Edentulous Ridges—A Photoelastic Study

Aim: To compare the type of stress distribution pattern occurring with anatomic and non-anatomic tooth forms beneath a complete denture in both maxillary and mandibular arch. Methodology: A photoelastic model of the edentulous maxillary and mandibular ridge was prepared meticulously to simulate the human mandible and maxilla. Two sets of acrylic teeth with anatomic and non-anatomic occlusal forms were used to fabricate upper and lower dentures. A vertical static load of 100 N was applied through the mandibular model to the maxillary model. After load application on the dentures the photoelastic model as well as the upper and lower complete dentures were sectioned in the midline. The sectioned photoelastic model was viewed through a polariscope to observe the fringe pattern indicating varying amounts of stress distribution. In this study, a two-dimensional photoelastic stress analysis technique was utilized. Results: Force per unit area was observed more in anatomic teeth than the non-anatomic counterpart. Hence anatomic tooth forms may increase the possibility of bone resorption rate over a period of time. However, in non-anatomic lower teeth, a decrease in value was observed from posterior to anterior region. Conclusion: Stress of greater magnitude was observed with cuspal teeth whereas non-anatomic (0°) showed slightly less magnitude of stress. Depending upon the clinical situation the clinician needs to choose the type of occlusal tooth forms for edentulous patients.

Charcot-Marie-Tooth病的诊治

Charcot-Marie-Tooth病(CMT)是最常见的一种遗传性周围神经病,是一组具有显著临床异质性和遗传异质性的疾病,主要表现为肢体远端肌肉进行性无力和萎缩,伴有轻到中度感觉减退,腱反射减弱和足部畸形等.近20年CMT致病基因的不断被克隆,其疾病分型、临床表型和基因表型的关系发生了巨大变化.本文主要阐述CMT的疾病分型演变、基因诊断策略、临床治疗进展.

Fate of root shell after pontic/socket shield techniques,is it better to extract the whole tooth?

A series of changes occur in the remaining alveolar process after whole tooth extraction.The basic question is,why do the bony walls(especially the labial/buccal)get resorbed immediately after the tooth is removed?This could be because,with cementum of the concerned tooth and its periodontal ligament,the supporting bundle bone is dependent on the presence of the tooth.This loss can be compensated using numerous techniques,such as socket grafting using various biomaterials to preserve the alveolar bone and buccal grafting with guided tissue regeneration to increase the thickness of buccal bone or placement of implant immediately.However,none of these techniques prevent the modelling of the alveolar bone post-extraction.Few studies have demonstrated that preservation of the roots in the alveolar process maintains the bone volume and facilitates vertical bone growth.A histological study in animals and humans has shown that the retained root shell does not pose any interference in the osseointegration of the implant(if placed simultaneously).Although various names have been proposed to describe the concept of retaining full or part of the root to prevent the resorption of the ridge,socket-shield and pontic-shield are the two most commonly used terms worldwide.The extraction of the whole tooth might be the choice of therapy when socket-shield or pontic-shield is not possible due to anatomical variations,infections,or lack of clinical expertise.Irrespective of the size,when a whole root or a root fragment(is left in situ),it is the dentist’s ethical duty to advise/inform the patient and ensure repeated clinical and radiographic follow-up.The present study aimed to highlight the current status of these techniques,their benefits,and possible complications and address whether the paradigm of the teeth extraction methods should be altered.

无线系统中Bluetooth链路的有效性及可靠性研究

本文通过蓝牙通信链路信道模型的自适应性研究,采用层次式编码方案和Turbo码编码技术,在蓝牙协议固有的编码基础上增加另一编码层,构成跨层的双重自适应结构,自适应于时变的信道特征和不同媒体业务的服务质量(QoS),最大限度地提高蓝牙无线链路的有效性和可靠性。

TOOTH CROWN DEFORMABLE DESIGN BASED ON DIRECT MANIPULATION OF FFD

A flexible and adaptable design method for the tooth crown is presented based on the direct manipulation of free-form deformation （FFD）. The correct shape of the tooth crown can be obtained by adding, modifying, and deleting constraint points or load points based on stretching and compressing operation. Finally, an example is given to illustrate the method to be efficient.

Charcot-Marie-Tooth病的研究与诊断进展

Charcot-Marie-Tooth病,是一组最常见的在遗传和临床上都具有高度异质性的家族性周围神经病,约占全部遗传性神经病的90%。其基本临床表现相似,目前已知的亚型多达35种,为该病的确诊带来极大困难。因此,本文综述该病各亚型的临床、电生理、周围神经病理、致病基因及有效诊断方法。