Davi Reis Calderoni

Cranial reconstruction: 3D biomodel and custom-built implant created using additive manufacturing.

Additive manufacturing (AM) technology from engineering has helped to achieve several advances in the medical field, particularly as far as fabrication of implants is concerned. The use of AM has made it possible to carry out surgical planning and simulation using a three-dimensional physical model which accurately represents the patients anatomy. AM technology enables the production of models and implants directly from a 3D virtual model, facilitating surgical procedures and reducing risks. Furthermore, AM has been used to produce implants designed for individual patients in areas of medicine such as craniomaxillofacial surgery, with optimal size, shape and mechanical properties. This work presents AM technologies which were applied to design and fabricate a biomodel and customized implant for the surgical reconstruction of a large cranial defect. A series of computed tomography data was obtained and software was used to extract the cranial geometry. The protocol presented was used to create an anatomic biomodel of the bone defect for surgical planning and, finally, the design and manufacture of the patient-specific implant.

Microstructural and Mechanical Characterization of a Custom-Built Implant Manufactured in Titanium Alloy by Direct Metal Laser Sintering

Custom-built implants manufacture has always presented difficulties which result in high cost and complex fabrication, mainly due to patients’ anatomical differences. The solution has been to produce prostheses with different sizes and use the one that best suits each patient. Additive manufacturing technology, incorporated into the medical field in the late 80s, has made it possible to obtain solid biomodels facilitating surgical procedures and reducing risks. Furthermore, this technology has been used to produce implants especially designed for a particular patient, with sizes, shapes, and mechanical properties optimized, for different areas of medicine such as craniomaxillofacial surgery. In this work, the microstructural and mechanical properties of Ti6Al4V samples produced by direct metal laser sintering (DMLS) are studied. The microstructural and mechanical characterizations have been made by optical and scanning electron microscopy, X-ray diffraction, and microhardness and tensile tests. Samples produced by DMLS have a microstructure constituted by hexagonal α′ martensite with acicular morphology. An average microhardness of 370 HV was obtained and the tensile tests showed ultimate strength of 1172 MPa, yield strength of 957 MPa, and elongation at rupture of 11%.

Paired evaluation of calvarial reconstruction with prototyped titanium implants with and without ceramic coating

PURPOSE To investigate the osseointegration properties of prototyped implants with tridimensionally interconnected pores made of the Ti6Al4V alloy and the influence of a thin calcium phosphate coating. METHODS Bilateral critical size calvarial defects were created in thirty Wistar rats and filled with coated and uncoated implants in a randomized fashion. The animals were kept for 15, 45 and 90 days. Implant mechanical integration was evaluated with a push-out test. Bone-implant interface was analyzed using scanning electron microscopy. RESULTS The maximum force to produce initial displacement of the implants increased during the study period, reaching values around 100N for both types of implants. Intimate contact between bone and implant was present, with progressive bone growth into the pores. No significant differences were seen between coated and uncoated implants. CONCLUSION Adequate osseointegration can be achieved in calvarial reconstructions using prototyped Ti6Al4V Implants with the described characteristics of surface and porosity.

Thoraco-omphalopagus asymmetric conjoined twins: Report of a case and complete review of the literature

Thoraco-omphalopagus asymmetric conjoined twinning is a rare condition in which a grossly defective foetus (the parasite) is attached to the thorax and upper abdomen of the main foetus (the autosite). We describe a case of thoraco-omphalopagus asymmetric conjoined twins in which the autosite had an associated large-diameter omphalocoele that was successfully separated at our institution. Reconstruction of the resulting abdominal-wall defect was performed using a flap from the gluteal region and the proximal portion of the inferior limb of the parasite, which is demonstrated. In addition, a review of all previously published cases is presented, showing that overall positive results can be obtained in treating this condition and that the presence and degree of cardiac involvement have a major influence on the prognosis.

Lower energy and pulse stacking. A safer alternative for skin tightening using fractional CO2 laser.

PURPOSE To evaluate the effect of different energies and stacking in skin shrinkage. METHODS Three decreasing settings of a fractional CO2 laser were applied to the abdomen of Twenty five Wistar rats divided into three groups. Group I (n=5) was histologically evaluated for microthermal zones dimensions. Groups II and III (n=10 each) were macroscopic evaluated with freeware ImageJ for area contraction immediately and after 30 and 60 days. RESULTS No statistical significance was found within microthermal zone histological dimensions (Group I) in all settings studied. (Ablation depth: 76.90 to 97.18µm; Coagulation depth: 186.01 to 219.84 µm). In Group II, macroscopic evaluation showed that all settings cause significant immediate skin contraction. The highest setting cause significant more intense tightening effect initially, contracting skin area from 258.65 to 179.09 mm2. The same pattern was observed in Group III. At 30 and 60 days, the lowest setting significantly sustained contraction. CONCLUSION Lower fractional CO2 laser energies associated to pulse stacking could cause consistent and long lasting tissue contraction in rats.

Biomateriais para reconstrução da órbita: revisão da literatura

O tratamento de lesoes traumaticas da orbita permanece um desafio para o cirurgiao maxilofacial. Quando a correcao cirurgica nao e realizada ou e feita de maneira inadequada, pode ocorrer enoftalmia, diplopia, distopia ocular, restricao da movimentacao ocular e disfuncao do nervo infraorbital. A importância da cirurgia consiste em liberar o tecido orbitario herniado pelo foco de fratura, restaurar a arquitetura normal da orbita, objetivando um resultado estetico e funcional adequado. Nas ultimas decadas, varios avancos ocorreram no tratamento cirurgico destas fraturas, bem como nos metodos diagnosticos. Com o desenvolvimento de tomografias computadorizadas de multiplos detectores, tornou-se possivel a analise tridimensional da orbita, assim como sua avaliacao volumetrica, o que revolucionou o manejo cirurgico destas fraturas. Outro fator com impacto direto nas reconstrucoes das orbitas e a disponibilidade de diversos biomateriais, para restauracao das paredes orbitarias. Assim, o objetivo desse artigo e revisar os materiais disponiveis para reconstrucao nos casos de fraturas do assoalho da orbita, comparar suas aplicabilidades praticas e destacar aqueles mais utilizados no Servico de Cirurgia Plastica do Hospital de Clinicas da Unicamp, nos ultimos anos. Dentre os materiais de escolha, em nosso Servico, destacamos o osso autogeno de calota craniana, a cartilagem de concha auricular, a tela de titânio e o polietileno poroso de alta densidade. Cada biomaterial apresenta indicacoes especificas, de acordo com as caracteristicas da fratura orbitaria, sendo considerados, para a escolha do material, os resultados a longo prazo e a experiencia do cirurgiao.

Does bronchopulmonary dysplasia change the postoperative outcome of herniorrhaphy in premature babies

Background:  Inguinal hernia is a common surgical condition in premature neonates. Because of physiological immaturity, they can present with lung‐related diseases, such as bronchopulmonary dysplasia (BPD), which may influence the time for operation and the postoperative outcome after hernia repair. The aim of this study was to analyze the role of BPD in the outcome of premature infants who underwent herniorrhaphy.

Retrospective analysis of 70 patients who underwent post-bariatric abdominoplasty with neo-omphaloplasty

Introduction: With the increasing surgical treatment of obesity, a new group of patients is being attended by plastic surgeons: those with large flaccid skin following weight loss. For patients treated with conventional or open bariatric surgery, vertical, anchor-line, or inverted “T” abdominoplasty has been widely used to improve the abdominal contour. In this study, abdominoplasty was associated with umbilical amputation followed by neo-omphaloplasty. Methods: Seventy patients with stable weight for at least 18 months underwent surgery at the UNICAMP Plastic Surgery Outpatient Clinic, from March 2011 to April 2013. In all patients, anchor-line abdominoplasty with excision of the original navel was executed, together with the surgical specimen and preparation of neo-umbilicus, through bilateral dermal-fat flaps. A retrospective analysis of medical records and photographic archives was performed. Results: The 70 patients were predominantly female (91%) and white (83%) with a mean age of 40 years. After a wait time of approximately 16 months, they were subjected to anchor-line abdominoplasty associated with neo-omphaloplasty, which lasted an average of 2 hours. There were post-operative complications in 29.85% of the patients, including small dehiscence, unsightly, enlarged, or hypertrophic scars, keloid, seroma, relevant dermo-fatty excesses, and wound infection. The neo-umbilicus obtained from the surgery is very similar to the original umbilicus. We did not observe necrosis, stenosis, morphological distortions, or bad positioning. Conclusion: This technique has made it possible to obtain an umbilicus with a natural look, is easy to perform, and shortens operating time.

Successful calvarial bone salvage using multiple outer table perforation technique on total scalp avulsion injury

For centuries, cranial outer table perforations were used to treat scalp avulsions that compromised the underlying periosteum. However, its use declined with the development of newer alternatives such as free-flap transpositions and scalp replantation. We report a case of extensive scalp avulsion with a large area of bone devoid of its periosteum. Outer calvarial plate perforations were drilled to promote granulation tissue growth. Skin grafts were used as a temporary coverage. The remaining scalp was then expanded, and the flaps obtained allowed a satisfactory coverage of the area of alopecia. The objective of this report is to bring this treatment method again into the set of possibilities to be considered when planning scalp reconstruction, as it is a feasible alternative and enables good results.

Estudo retrospectivo da abordagem das fraturas nasais no Hospital de Clínicas da Unicamp

Introduction: Nasal fractures are common injuries, frequently considered to be minor. Nevertheless, they may cause significant damage, from both a functional and aesthetic perspective. Methods: Medical records of 144 patients admitted for nasal fracture treatment between February 2002 and October 2008 to the Plastic Surgery Area of the Unicamp Clinical Hospital were analyzed. Results: Patients were predominantly male (75.7%), with a male to female ratio of 3.1:1. The most number of cases was observed in 21 to 30 year olds, and the majority of fractures (31.8%) were caused by physical aggression. Closed reductions were performed on all patients under local and topical anesthesia after an average of 8 days. Among the studied patients, 31 experienced residual deformity. Conclusions: Patients typically affected by nasal fractures are young male adults. Closed reduction surgical treatment yields acceptable results, with correct injury evaluation and treatment timing.