Effect of Wearing a Maxillofacial Prosthesis on Masticatory Rhythm Improvement in Mandibulectomy Patients

Background: Recording jaw movement rhythms in patients with jaw defects is challenging using conventional tracking devices. However, masticatory rhythm is crucial for masticatory performance and nutritional intake. This study aimed to explore the impact of using a maxillofacial prosthesis to restore masticatory rhythm in mandibulectomy patients with a novel wearable device. Methods: Twelve patients who underwent mandibulectomy and were rehabilitated with maxillofacial prosthesis were recruited. Chewing rate, cycle durations, coefficient of variation of cycle durations (CV), changing times of skin morphology on the back of the ear pinna area (SM), and masticatory performance were measured during gum chewing without and with a denture using a wearable jaw movement rhythm tracking device. A paired t-test and the Pearson correlation coefficient were used for statistical analysis. Results: The chewing rate increased by 8.6 cycles/min with dentures (P P = 0.01). The CV and SM decreased with dentures (P = 0.004 and P = 0.01, respectively). Significant correlations were found between the CV and SM without dentures (P = 0.004). Conclusion: 1. Wearing maxillofacial prostheses can improve masticatory rhythm in patients who undergo mandibulectomy with Eichner B2 occlusal supports. 2. The wearable device is available for measuring masticatory rhythm in patients with jaw defects in clinics. 3. Changing times of the skin morphology on the back of the ear pinna indicate jaw movement stability through a simpler process than the coefficient of variation of cycle durations.

Transfer film effects induced by 3D-printed polyether-ether-ketone with excellent tribological properties for joint prosthesis

Based on the building principle of additive manufacturing,printing orientation mainly determines the tribological properties of joint prostheses.In this study,we created a polyether-ether-ketone(PEEK)joint prosthesis using fused filament fabrication and investigated the effects of printing orientation on its tribological properties using a pin-on-plate tribometer in 25% newborn calf serum.An ultrahigh molecular weight polyethylene transfer film is formed on the surface of PEEK due to the mechanical capture of wear debris by the 3D-printed groove morphology,which is significantly impacted by the printing orientation of PEEK.When the printing orientation was parallel to the sliding direction of friction,the number and size of the transfer film increased due to higher steady stress.This transfer film protected the matrix and reduced the friction coefficient and wear rate of friction pairs by 39.13%and 74.33%,respectively.Furthermore,our findings provide a novel perspective regarding the role of printing orientation in designing knee prostheses,facilitating its practical applications.

Indication and surgical approach for reconstruction with endoprosthesis in bone-associated soft tissue sarcomas:Appropriate case management is vital

It is important for surgeons performing sarcoma surgery to know that bone resection and tumor prosthesis applications in soft tissue sarcomas(STS)have unique features in terms of indication,surgical approach and follow-up,in terms of the management of these cases.Some STS are associated with bone and major neurovascular structures.Bone-associated STS are generally relatively large and relatively deep-seated.Additionally,the tendency for metastasis is high.In some cases,the decision about which structures to resect is difficult.These cases are often accompanied by poor oncological and surgical outcomes.Management of cases should be done by a multidisciplinary team in advanced centers specialized in this field.The surgical team must have sufficient knowledge and experience in the field of limb-sparing surgery.Preoperative evaluation and especially good planning of bone and soft tissue reconstruction are vital.

Gait Analysis of a Subject with Tarsometatarsal Prosthesis

Introduction: Gait analysis of an adult man after trans-metatarsal unilateral amputation is described. Objective: Instrumental gait analysis of a subject 15 years after trans-metatarsal unilateral amputation in two footwear conditions: while walking barefoot and with prosthesis. Materials and Methods: In a movement analysis laboratory, locomotion studies were carried out at freely chosen walking speed by a 65-year-old subject, obtaining kinematic, kinetic and surface electromyographic data in time and space. Gait analysis was performed using instrumental technologies from a digital eco-system applying walking protocols. Results: When the patient wore the prosthesis, several positive improvements were observed in various aspects of gait. These included enhancements in the base of support, gait speed, and joint range of movements. Additionally, there was a slight improvement in the vertical ground reaction forces pattern, indicating a positive effect of the assistive technology. Furthermore, the use of the prosthesis led to a more organized pattern of muscle activity, which further supports its beneficial impact. However, it is worth noting that some challenges still persisted, particularly regarding stabilizing the body during the double support phase. Despite this difficulty, the overall findings suggest that the use of the prosthesis offers valuable improvements to the patient’s gait dynamics. Conclusions: After conducting a thorough analysis of the parameters related to the gait of a subject who underwent a trans-metatarsal unilateral amputation fifteen years ago, it was found that the use of prosthesis had a positive impact. This study demonstrated important improvements in some kinematic and kinetic parameters, including muscle activation patterns, indicating an increase in comfort and confidence while utilizing the prosthetic device.

Electrophysiological evaluation of alterations in penile sensation due to penile prosthesis implantation in patients with erectile dysfunction

Objective The present study was aimed to determine the effect of penile prosthesis implantation(PPI)surgery on penile sensation by evaluating the penile electromyography(EMG)variables.Methods The research was designed as a prospective study.Thirty patients who were diagnosed with organic erectile dysfunction and had underwent PPI surgery between January 2017 and January 2018 in the Urology Clinic of Antalya Training and Research Hospital were included in this study.Penile sensory EMG was performed on each patient 1 day prior to the surgery by the Physical Therapy and Rehabilitation clinic.Additionally,the control EMG study was also performed in the 3rd and 6th postoperative months.Results We included 27 patients in this study who attended regular follow-ups and had complete EMG results.Out of the 27 patients,23(85.2%)patients had received malleable(ProMedon)penile prosthesis,one(3.7%)patient had received a two-piece inflatable(Ambicor)penile prosthesis,and three(11.1%)patients had received a three-piece inflatable(AMS 700 CXR)penile prosthesis.The mean nerve conduction value(NCV)of the patients was 29.85(standard derivation:22.54;range:0-78.4)m/s during the preoperative period,whereas it was 27.64(standard derivation:24.72;range:0-83.3)m/s in the 3rd postoperative month and 24.80(standard derivation:22.31;range:0-88.4)m/s in the 6th postoperative month.There was no significant difference between preoperative NCV and 3rd postoperative month NCV(p=0.607).Similarly,no significant difference was observed between preoperative NCV and 6th postoperative month NCV(p=0.276).Additionally,the change between NCV values at postoperative 3rd and 6th months was not statistically significant(p=0.553).Conclusion Significant loss of penile sensation does not occur in patients who undergo PPI surgery.

A new passive transfemoral prosthesis mechanism based on 3R36 knee and ESAR foot providing walking and squatting

Researchers have proposed various linkage mechanisms to connect knee and ankle joints for above-knee prosthe-ses,but most of them only offer natural walking.However,studies have shown that people assume a squatting posture during daily activities.This paper introduces a novel mechanism that connects the knee joint with the foot-ankle joint to enable both squatting and walking.The prosthetic knee used is the well-known 3R36,while the energy storing and return(ESAR)prosthetic foot is used for the ankle-foot joint.To coordinate knee and ankle joint movements,a six-bar linkage mechanism structure is proposed.Simulation results demonstrate that the proposed modular transfemoral prosthesis accurately mimics the motion patterns of a natural human leg during walking and squatting.For instance,the prosthesis allows a total knee flexion of more than 140°during squatting.The new prosthesis design also incorporates energy-storing mechanisms to reduce energy expenditure during walking for amputees.

Current situation and development of facial prosthesis

Facial prostheses have developed significantly in the last 10 years,especially between 2016 and 2021.This development is mainly due to the great progress made in the fields of biocompatible materials,digital technology,and three-dimensional printing technology,which provides guarantee for low allergy,high biosimulation,comfort,and satisfactory usability.Treatment teams typically consist of plastic surgeons,material experts,engineers,and computer scientists who have extensive clinical experience.These teams successfully implement an integrated,multidisciplinary model by prioritizing the reasonable expectations of both the physician and patient,leading to improved patient satisfaction and compliance with prosthetic constraints.This study aimed to review the concept,development status,existing problems,and future of facial prosthesis.

An Optoelectronic Pulse Frequency Modulation Circuit for Retinal Prosthesis

A pulse frequency modulation（PFM） circuit for retinal prosthesis,which generates electrical pulses with frequency proportional to the intensity of incident light, is presented. The fundamental characteristic of the circuit is described and analyzed. The circuit is realized in 0.6μm CMOS process,and the simulation results testify to the possibility of sub-retinal implantation.

REALIZATION OF ALGORITHM OF TOOL PATH GENERATION FOR NC MACHINING OF MOLAR PROSTHESIS

The CAD model of molar prosthesis is usually stored in standard templete library （STIr） format. A new topological structure is given based on STL format and the vertex-based entity offset algorithm is presented to realize the rapid generation of roughing/finishing tool path for molar prosthesis. Simulation results show that the proposed algorithm prossesses characteristics of excellent stabilization, fast calculation speed and high machining accuracy.

Development and clinical application of a new testicular prosthesis

A new type of testicular prosthesis made of silastic with an elliptical shape to mimic a normal testis was developed by our team and submitted for patenting in China. The prosthesis was produced in different sizes to imitate the normal testis of the patient. To investigate the effects and safety of the testicular prosthesis, 20 patients receiving testicular prosthesis implantation were recruited for this study. Follow-up after 6 months revealed no complications in the patients. All the patients answered that they were satisfied with their body image and the position of the implants, 19 patients were satisfied with the size and 16 patients were satisfied with the weight. These results show that the testicular prosthesis used in this study can meet patient＇s expectations. Patients undergoing orchiectomy should be offered the option to receive a testicular prosthesis implantation. The dimensions and weight of the available prosthetic implants should be further addressed to improve patient satisfaction.

Treatment of acute periprosthetic infections with prosthesis retention: Review of current concepts

Periprosthetic joint infection(PJI) is a devastating complication after total joint arthroplasty, occurring in approximately 1%-2% of all cases. With growing populations and increasing age, PJI will have a growing effect on health care costs. Many risk factors have been identified that increase the risk of developing PJI, including obesity, immune system deficiencies, malignancy, previous surgery of the same joint and longer operating time. Acute PJI occurs either postoperatively(4 wk to 3 mo after initial arthroplasty, depending on the classification system), or via hematogenous spreading after a period in which the prosthesis had functioned properly. Diagnosis and the choice of treatment are the cornerstones to success. Although different definitions for PJI have been used in the past, most are more or less similar and include the presence of a sinus tract, blood infection values, synovial white blood cell count, signs of infection on histopathological analysis and one ormore positive culture results. Debridement, antibiotics and implant retention(DAIR) is the primary treatment for acute PJI, and should be performed as soon as possible after the development of symptoms. Success rates differ, but most studies report success rates of around 60%-80%. Whether single or multiple debridement procedures are more successful remains unclear. The use of local antibiotics in addition to the administration of systemic antibiotic agents is also subject to debate, and its pro's and con's should be carefully considered. Systemic treatment, based on culture results, is of importance for all PJI treatments. Additionally, rifampin should be given in Staphylococcal PJIs, unless all foreign material is removed. The most important factors contributing to treatment failure are longer duration of symptoms, a longer time after initial arthroplasty, the need for more debridement procedures, the retention of exchangeable components, and PJI caused by Staphylococcus(aureus or coagulase negative). If DAIR treatment is unsuccessful, the following treatment option should be based on the patient health status and his or her expectations. For the best functional outcome, one- or two-stage revision should be performed after DAIR failure. In conclusion, DAIR is the obvious choice for treatment of acute PJI, with good success rates in selected patients.

Prospective and long-term evaluation of erect penile length obtained with inflatable penile prosthesis to that induced by intracavernosal injection

We compared erect penile length after inflatable penile prosthesis （IPP） implantation with that induced by intracavemosal injection （ICI） before surgery. A total of 11 patients with full erections induced by ICI of 0.25 mL of Trimix （papaverine, phentolamine and prostaglandin E 1） at the time of penile color duplex Doppler ultrasonograpby were enrolled in this study. The patients subsequently underwent IPP implantation as the ultimate treatment for their erectile dysfunction （ED）. Erect penile length consequent to IPP implantation was measured at 6 weeks, 6 months and at I year after surgery. The Sexual Health Inventory for Men （SHIM） was administered before, and at 6 months and 1 year after IPP implantation. Erect penile length （mean ± s.c.） as induced by ICI was 13.2 ± 0.4 cm, whereas the lengths attained with IPP were 12.4 ± 0.3, 12.5 ± 0.3 and 12.5 ± 0.4 cm at the sixth week, sixth month and 1-year follow-ups, respectively. There were 0.83 ± 0.25, 0.75 ± 0.20 and 0.74 ± 0.15 cm decreases in erect penile length at 6 weeks, 6 months and 1 year, respectively, after IPP implantation when compared with that after ICI （P 〈 0.05）. The SHIM scores for patients reporting shorter penises were the same as those for patients without complaints at the 6-month and 1-year follow-ups （P 〉 0.05）. To our knowledge, this is the first study to objectively show a significant decrease in erect penile length after IPP implantation when compared with that after ICI. However, this decrease did not affect the effectiveness of IPP in treating ED.

Penile prosthesis implantation and tunica albuginea incision without grafting in the treatment of Peyronie＇s disease with erectile dysfunction

We evaluated penile prosthesis implantation with tunica albuginea-relaxing incisions without grafting in the treatment of Peyronie＇s disease associated with erectile dysfunction. Between April 2005 and June 2011, 62 patients underwent surgery due to severe Peyronie＇s disease associated with erectile dysfunction. Malleable and inflatable penile prostheses were inserted in 49 and 13 cases, respectively. Penile prostheses were inserted into the corpora cavernosa using the standard ventral approach. After lifting the neurovascular bundle, the tunica albuginea was incised and opened at the plaque region to correct the deformities and to lengthen the penis. Subsequently, the wide neurovascular bundle was replaced, and all incisions of the tunica albuginea were covered to prevent corporal grafting. In the median follow-up of 35 months （range 14-82 months）, the penis was completely straightened in 59 （95%） patients. Numbness of the glans, which the patients found initially upsetting, decreased or disappeared spontaneously 3-6 months later. Penile prosthesis implantation with tunica albuginea incisions is a viable alternative in the treatment of Peyronie＇s disease because the extensive dissection of the neurovascular bundle allows a good approach to the plaque and provides excellent covering of the incised tunica albuginea without additional grafting.

Infection associated with hydroxyapatite prosthesis and related factors

Background The purpose of otomicrosurgery in modern times is to achieve complete removal of disease, which is the basis for hearing rehabilitation. Artificial ossicles are important for hearing rehabilitation. One of the materials is hydroxyapatite that acts as ossicular replacement prosthesis (HA prosthesis, PORP & TORP) and is commonly used as substitute bone in clinics. Although HA prostheses feature good biocompatibility, stability and certain resistance to infection, the structure of the material can be decomposed and absorbed. Based upon animal experiments and clinical application, this article explores the infectivity of HA prostheses and influencing factors. Materials and Methods HA prostheses were implanted in the bulla in guinea pigs. Infected HA prostheses were examined under a scanning electron microscope. Ninety patients implanted with HA prostheses were followed for more than 3 months. Five cases that had undergone revision operations were reported. Results Scanning electronic microscopy showed that the normal compact structures had disappeared and become loose in infected HA prostheses, with their micropores infiltrated with effusion, fibrous tissue and inflammatory cells. As a result, the normal ceramic structure was decomposed and the micropores structure disappeared. The infected mesotympanum in the reported cases also led to HA infection. The shape and structure of bone were destroyed, which was visible by visual examination and light microscopy. The process of cholesteatoma recurrence was always associated with infection, although the HA prosthesis was sometimes spared. Conclusion While HA prosthesis is anti-infective to some extent, long-term infection and cholesteatoma recurrence can lead to destruction and decomposition of HA prostheses. Long-term infected middle ear cavity, dysfunctional Eustachian tube, residual and recurrent cholesteatoma and other factors can cause decomposition of HA prosthesis and result in hearing loss.

Penile prosthesis implantation in Chinese patients wit severe erectile dysfunction： 10-year experience

We retrospectively evaluated the clinical outcome of penile prosthesis implantation （PPI） in Chinese patients with severe erectile dysfunction （SED）. From July 2000 to December 2011, 224 patients （mean age： 35.9±11.8 years, range： 20-75 years） with SED underwent PPI by experienced surgeon according to standard PPI procedure at our centre. A malleable prosthesis （AMS 650） was implanted in 45 cases （20.1%）, and a three-piece inflatable prosthesis （AMS 700 CXM or AMS 700 CXR） was implanted in 179 cases （79.9%）. Surgical outcomes, including postoperative complications, clinical efficacy and couple satisfaction, were evaluated over than 6 months postoperatively using medical record abstraction, IIEF-5, quality of life （QoL） scores, and the patient/partner sexual satisfaction score proposed by Bhojwani etaL Of the 224 patients eligible for the study, 201 subjects （89.7%） completed follow-up. All of patients could perform sexual intercourse post PPI with the mean postoperative IIEF-5 and QoL scores were 20.02±2.32 and 5.28±0.76, respectively, which were significantly improved compared with the preoperative scores （6.29±1.5 and 2.13±0.84, P〈0.01）. Of the 201 men, mechanical malfunction occurred in four cases （2.0%） and three cases were re-implanted new device, and two cases （1.0%） developed a mild curvature of the penis. Scrotal erosion with infection occurred in one case with diabetes mellitus （0.5%） and required complete removal of the implanted AMS 700 CXM. Satisfactory sexual intercourse at least twice per month was reported by 178 men （88.6%）, and overall satisfaction with the PPI surgery was reported by 89.0% of men and 82.5% of partners. Patient satisfaction in the three-piece inflatable prosthesis group was higher than in the malleable prosthesis group （P〈0.05）. Satisfaction, however, between the types of prostheses, did not differ in the partner survey. PPI is a safe and effective treatment option for Chinese patients with SED and experienced surgeon perform PPI according to standard PPI procedure could reduce the postoperative complications of PPI and could improve patient satisfaction ratio and QoL.

Can periprosthetic hip joint infections be successfully managed by debridement and prosthesis retention?

To evaluate the current literature about how successfully periprosthetic hip joint infections can be managed by debridement and prosthesis retention.A literature search was performed through Pub Med until September 2013.Search terms were"DAIR(debridement,antibiotics,irrigation,and retention)"alone and in combination with"hip"as well as"hip infection+prosthesis retention".A total of 11 studies reporting on 292 cases could be identified.Five different treatment modalities have been described with varying success rates(debridement-21%infection eradication rate;debridement+lavage-75%infection eradication rate;debridement,lavage,with change of modular prosthesis components-70.4%infection eradication rate;debridement,lavage,change of modular prosthesis components+vacuum-assisted closure-92.8%infection eradication rate;acetabular cup removal+spacer head onto retained stem-89.6%infection eradication rate).With regard to the postoperative antibiotic therapy,no general consensus could be drawn from the available data.Debridement,antibiotic therapy,irrigation,and prosthesis retention is an acceptable solution in the management of early and acute hematogenous periprosthetic hip joint infections.The current literature does not allow for generalization of conclusions with regard to thebest treatment modality.A large,multi-center study is required for identification of the optimal treatment of these infections.

Factors influencing utilization and satisfaction with external breast prosthesis in patients with mastectomy:A systematic review

Purpose:The aim of this study is to describe and analyse the factors which influence utilization of EBPs among breast cancer patients worldwide and particularly in China.Methods:Literature searches were conducted in Wanfang,CNKI,and PubMed databses in order to identify relevant articles published in both Chinese and English up to October 2014.The phrase“external breast prosthesis”in Chinese was used to search titles,abstracts,and key words to find articles in Wanfang and CNKI electronic databases.Synonyms and related terms for external breast prosthesis were combined and used for searches performed in PubMed.Additional references were subsequently extracted from the bibliographies of all included articles and reviews.Qualitative analysis was applied in this study rather than meta-analysis.Results:The number of relevant studies published in other countries is five times greater than the literature published in China,with most articles written by Australian scientists.Based on the existing references,reconstruction,comfort,appearance,cost,mental status,and supportive information were the main factors influencing choice of treatment options by patients.Conclusion:Six main factors influencing EBP use worldwide were identified.Although the number of breast cancer cases per year is increasing at a much higher rate in China relative to the average number globally,relevant studies on Chinese patients are lacking.Thus,further studies should be undertaken in China in order to develop effective service modalities in order to improve quality of life of patients.

Ocular prosthesis incorporating IPS e-max press scleral veneer and a literature review on non-integrated ocular prosthesis

The article highlights a new method for the fabrication of an ocular prosthesis by the incorporation of a ceramic scleral veneer. The steps of fabrication include impression making, wax try-in, performing a “cut-back” on a selected stock eye, insertion of the IPS e-max press scleral veneer, finishing and insertion. It also includes a detailed review on non-integrated ocular prostheses.

Penile prosthesis implantation in a transsexual neophallus

Reconstruction surgery for a female to male transsexual usually involves mastectomy, hysterectomy and creating anaesthetically appealing neophallus. We have successfiflly inserted an inflatable prosthesis using the AMS CX prosthesisin a 45 year old transsexual, who had a large bulky neophallus constructed from the anterior abdominal subcutaneousfat, about 9 years ago. The single cylinder CX prosthesis was well anchored to the symphysis pubis using a dacronwindsock tubing, the activation pump was placed in the dependent pouch of the right labium and the reservior in theusual perivesical space. The patient subsequently had debulking procedure using liposuction to create a more aestheticand functional phallus. To date, the inflatable neophallus prosthesis is functioning well. (Asian J Androl 2000 Dec;2: 304-306)

Customized reconstructive prosthesis design based on topological optimization to treat severe proximal tibia defect

A novel reconstructive prosthesis was designed with topological optimization(TO)and a lattice structure to enhance biomechanical and biological properties in the proximal tibia.The biomechanical performance was validated through finite element analysis(FEA)and biomechanical tests.The tibia with inhomogeneous material properties was reconstructed according to computed tomography images,and different components were designed to simulate the operation.Minimum compliance TO subject to a volume fraction constraint combined with a graded lattice structure was utilized to redesign the prosthesis.FEA was performed to evaluate the mechanical performances of the tibia and implants after optimization,including stress,micromotion,and strain energy.The results were analyzed by paired-samples t tests,and p<0.05 was considered significant.Biomechanical testing was used to verify the tibial stresses.Compared to the original group(OG),the TO group(TOG)exhibited lower stress on the stem,and the maximum von Mises stresses were 87.2 and 53.1 MPa,respectively,a 39.1%reduction(p<0.05).Conversely,the stress and strain energy on the tibia increased in the TOG.The maximum von Mises stress values were 16.4 MPa in the OG and 22.9 MPa in the TOG with a 39.6%increase(p<0.05),and the maximum SED value was 0.026 MPa in the OG and 0.042 MPa in the TOG,corresponding to an increase of 61.5%(p<0.05).The maximum micromotions in the distal end of the stem were 135μm in the OG and 68μm in the TOG,almost a 50%reduction.The stress curves of the biomechanical test coincided well with the FEA results.The TO approach can effectively reduce the whole weight of the prosthesis and improve the biomechanical environment of the tibia.It could also pave the way for next-generation applications in orthopedics surgery.