An Analysis of the Biocompatibility, Cytotoxicity, and Bone Conductivity of Polycaprolactone: An In Vivo Study.

BACKGROUND: Tissue engineering represents a promising field in regenerative medicine, with bioresorbable polymers such as polycaprolactone (PCL) playing a crucial role as scaffolds. These scaffolds support the growth and repair of tissues by mimicking the extracellular matrix. OBJECTIVE: This study aimed to assess the in vivo performance of three-dimensional PCL scaffolds by evaluating their effects on bone repair in rat calvaria and the tissue reaction in subcutaneous implant sites, as well as their impact on major organs such as the kidneys, lungs, and liver. METHODS: Three-dimensional scaffolds made of PCL were implanted in the subcutaneous tissue of rats' backs and calvaria. Histological analyses were conducted to observe the bone repair process in calvaria and the tissue response in subcutaneous implant sites. Additionally, the kidneys, lungs, and livers of the animals were examined for any adverse tissue alterations. RESULTS: The histological analysis of the bone repair in calvaria revealed newly formed bone growing towards the center of the defects. In subcutaneous tissues, a thin fibrous capsule with collagenous fibers enveloping the implant was observed in all animals, indicating a positive tissue response. Importantly, no harmful alterations or signs of inflammation, hyperplasia, metaplasia, dysplasia, or hemorrhage were detected in the kidneys, lungs, and liver. CONCLUSIONS: The findings demonstrate that PCL scaffolds produced through additive manufacturing are biocompatible, non-cytotoxic, and bioresorbable, promoting osteoconduction without adverse effects on major organs. Hence, PCL is confirmed as a suitable biomaterial for further studies in tissue engineering and regenerative medicine.

The Hyrax appliance with tooth anchorage variations in surgically assisted rapid maxillary expansion: a finite element analysis.

PURPOSE: It is known that a correct transverse maxillary dimension is a key factor for a stable occlusion, which brings functional and esthetic benefits for the patient. In patients presenting maxillary atresia and the completion of bone growth, a highly recommended option for correction is the surgically assisted rapid maxillary expansion (SARME) associated with the Hyrax appliance. The objective of this study was to evaluate the influence of tooth anchorage variations of the Hyrax appliance in SARME through finite element analysis, evaluating which anchorage option might be associated with more effective orthopedic results with less undesired side effects. METHODS: Five different dental anchoring conditions for the Hyrax appliance were simulated through FE analysis applying premolars and molars as anchorage, having the same force applied by the activation of the Hyrax screw (0.5 mm) in all groups. The maxillary displacement results (axes X, Y, and Z) and generated stresses for both teeth and maxillary bone were calculated and represented using a color scale. RESULTS: All groups presented significant bone displacement and stress concentration on anchoring teeth, with the group presenting anchorage in the 1st and 2nd molars showing the greatest maxillary horizontal displacement (axis X) and suggesting the lowest tendency of dental vestibular inclination. CONCLUSIONS: Variations in dental anchorage might substantially affect the maxillary bone and teeth displacement outcome. The protocol for the Hyrax apparatus in SARME applying the 1st and 2nd molars as anchorage might generate less tilting and inclination of the anchoring teeth.

Oral health-related quality of life in women with temporomandibular joint disk anterior displacement before and after disk repositioning and anchoring surgery assessed with the Oral Health Impact Profile (OHIP-14).

OBJECTIVES: The aim of this study was to assess and compare oral health-related quality of life (OHRQOL) in women with temporomandibular joint (TMJ) disk displacement without reduction, before disk repositioning and anchoring surgery, in short-term follow-up, in different age groups, and with use of the Oral Health Impact Profile (OHIP-14). STUDY DESIGN: Fifty women ages between 17 and 60 years were divided into 4 age groups: 17-27, 28-38, 39-49, and 50-60 years. All the patients were asked to answer the OHIP-14 form before surgery and during their short-term follow-up. Seven domains of OHRQOL were rated on a 5-point Likert scale from 0 (never) to 4 (very often). Domains' scores and total OHIP-14 were compared between times by using Student's t test in the whole sample and in the 4 age groups. RESULTS: Both the whole sample and the age groups (17-27, 28-38, 39-49 years) showed a statistically significant decrease in all scores (P < .01). The age group 50-60 years showed a decrease in scores significant only in functional limitation (P = .05) CONCLUSIONS: TMJ disk anterior displacement had a negative impact on women's OHRQOL because of physical pain, physical disability, and psychological discomfort. TMJ disk repositioning and anchoring surgery improved overall OHRQOL in patients between 17 and 49 years of age; however, in patients between 50 and 60 years of age, there was improvement only in physical pain.

Solitary plasmacytoma of the jaws: therapeutical considerations and prognosis based on a case reports systematic survey / Solitary plasmacytoma of the jaws: therapeutical considerations and prognosis based on a case reports systematic survey

Abstract Introduction: Solitary plasmacytoma is a rare malignant tumor of plasma cells with no evidence of systemic proliferation. There are two known subtypes: extramedullary solitary plasmacytoma and solitary bone plasmacytoma. The etiology is still unknown. Both lesions present a risk of progression to multiple myeloma. A number of approaches have been used for treatment of solitary plasmacytoma. Objective: To carry out a systematic review of the case reports described in the literature, focusing on therapeutic and prognostic aspects. Methods: A search of clinical case reports was performed in the PubMed database using Mesh Terms related to "plasmacytoma" under the following criteria: type of study (case report), articles in English language, conducted in humans, with no publication date limits. Results: Of the 216 articles found, only 21 articles met the pre-established inclusion criteria. Conclusion: The occurrence of solitary bone plasmacytoma in the bones of the face is a rare condition prevalent between the 4th and 6th decades of life, located in the posterior region of the mandible in most cases. Histopathological examination and systemic investigation are mandatory for confirmation of diagnosis.

Resumo: Introdução: O plasmocitoma solitário é um tumor maligno raro de células plasmáticas sem evidência de proliferação sistêmica e engloba dois subtipos: plasmocitoma solitário extramedular e plasmocitoma solitário ósseo. A etiologia ainda é desconhecida. Ambas as lesões apresentam risco de progressão para mieloma múltiplo. Uma série de abordagens tem sido usada para seu tratamento. Objetivo: Realizar uma revisão sistemática da literatura com enfoque nos aspectos terapêuticos e prognósticos. Método: Realizou-se uma busca de relatos de caso clínico na base de dados PubMed com termos de busca relacionados com "plasmocitoma" sob os seguintes critérios: tipo de estudo (relato de caso), artigos na língua inglesa, estudos realizados apenas em humanos, sem limites de data de publicação. Resultados: Dos 216 artigos encontrados, apenas 21 preencheram os critérios de inclusão pré-estabelecidos. Conclusão: A ocorrência de plasmocitoma solitário ósseo nos ossos da face é uma condição rara prevalente entre a 4a e a 6a décadas de vida, localizada na região posterior de mandíbula na maioria dos casos. O exame histopatológico e a investigação sistêmica são mandatórios para confirmação do diagnóstico.

Solitary plasmacytoma of the jaws: therapeutical considerations and prognosis based on a case reports systematic survey.

INTRODUCTION: Solitary plasmacytoma is a rare malignant tumor of plasma cells with no evidence of systemic proliferation. There are two known subtypes: extramedullary solitary plasmacytoma and solitary bone plasmacytoma. The etiology is still unknown. Both lesions present a risk of progression to multiple myeloma. A number of approaches have been used for treatment of solitary plasmacytoma. OBJECTIVE: To carry out a systematic review of the case reports described in the literature, focusing on therapeutic and prognostic aspects. METHODS: A search of clinical case reports was performed in the PubMed database using Mesh Terms related to "plasmacytoma" under the following criteria: type of study (case report), articles in English language, conducted in humans, with no publication date limits. RESULTS: Of the 216 articles found, only 21 articles met the pre-established inclusion criteria. CONCLUSION: The occurrence of solitary bone plasmacytoma in the bones of the face is a rare condition prevalent between the 4th and 6th decades of life, located in the posterior region of the mandible in most cases. Histopathological examination and systemic investigation are mandatory for confirmation of diagnosis.

Primary Repair of a Complex Panfacial Fracture by Dog Bite.

Facial fractures due to dog attacks have an unknown incidence rate. To date, only 41 cases of canine bite trauma in a pediatric patient, associated with facial fracture, have been reported in the literature. As major species of involving dogs are the American pitbull terrier and rottweiler. Due to the intense kinematics of this trauma, the treatment becomes complex. Thus, attention to the primary repair of such complex lesions ensures satisfactory results, which is the focus of this discussion. The purpose of this review was to analyze how different ways to approach this type of trauma in children for clarification or correct management. In addition, we address the treatment plan of a complex case of panfacial fracture by a canine bite in a 4-year-old patient. According to a review addressed, the main involved are orbit, nasal, and zygomatic. Antibiotic therapy is indicated for infected bite wounds and wounded considerations at risk of infection, with high complexity and when involving important structures such as bones, vessels, and joints. The state of tetanus immunization and the risk of rabies infection should be routinely addressed in the management of the bite wound.

Assessment of the Postoperative Stability of Mandibular Orthognathic Surgery for Correction of Class III Skeletal Malocclusion.

To assess the stability of mandible position after orthognathic surgery for correction of class III skeletal malocclusion. Twenty adult males, aged 18 to 40 years, with Angle class III skeletal malocclusion underwent preoperative orthodontic treatment for elimination of dental compensations followed by combined maxillomandibular surgery with rigid internal fixation. Lateral cephalograms from each patient, obtained in the natural head position before surgery, immediately after surgery, and at 6-month follow-up, were retrieved from the files of the Pontifical Catholic University of Rio Grande do Sul outpatient Oral and Maxillofacial Surgery clinic and compared. Comparison of craniometric landmark measurements showed that the precision of mandibular setback was compromised in the horizontal plane, with a mean mandibular relapse of 37.75% at point B and 45.85% at point Pg. Improved intercuspation and adaptation of the musculature to the new position of the jaws after orthognathic surgery lead to counterclockwise rotation of the mandible, ultimately displacing the mandible more anteriorly than desired.

Modified submandibular access for open reduction and internal rigid fixation in condylar fractures.

PURPOSE: The purpose of the present study was to describe a surgical technique for treatment of condylar fractures through the modified submandibular access, by means of a small incision in the mandibular angle that promotes a dissection between the parotideomasseteric and the transmasseteric fascia in a quick way and with low morbidity. Fixation may be made with plates and screws according to the technique prescribed by the surgeon. METHODS: Owing to the high incidence and importance of condylar fractures, various therapeutic methods have been described and may be divided into conservative and surgical methods. Various open surgical techniques are recommended in the treatment of mandibular condylar fractures, and the methods of internal rigid fixation and surgical accesses vary. The techniques that offer an adequate treatment of these fractures with shorter surgical time very often remain matters of controversy among surgeons. The procedure must guarantee maximum safety for the facial nerve and must provide a good cosmetic outcome, besides providing a suitable surgical field. RESULTS: A modified submandibular access is a safe and reproducible procedure providing excellent functional results. This procedure has been routinely performed in our department.

Reduction and fixation of mandibular condylar fractures with neck screw.

PURPOSE: The purpose of the present study is to describe a surgical technique for the treatment of condylar fractures using an intramedullary screw. MATERIALS AND METHODS: The treatment of these fractures remains very controversial. At the time of the choice of the surgical treatment, a wide range of accesses and of techniques of reduction and fixation is used, depending on the type of the fracture, the experience of the surgeon, and aesthetical issues. Among the difficulties posed by this type of fracture is the correct repositioning of the fractured condylar portion for which we have developed a technique that uses a neck screw, with intramedullary insertion. Because this is a round-headed screw, it is necessary to install a plate, which may be straight or "L" shape, and is placed perpendicular and superjacent to the screw so that it does not allow the rotation of the condylar portion. RESULTS: Neck screw can be used, resulting in satisfactory stability, for the reduction and fixation of these fractures.

Uma nova técnica de fixação de fratura condilar / A new condylar fracture fixation technique

Fraturas de côndilo são comuns, e a melhor maneira de tratá-las tem sido extensivamente discutida na literatura. Há basicamente dois métodos distintos para tratar fraturas de côndilo, o método funcional e o método cirúrgico. No presente estudo, o paciente foi submetido à anestesia geral para realizar o método de redução aberta com fixação interna. Após ser realizada uma abordagem submandibular para acessar a região da fratura, uma perfuração, usando broca, foi realizada na base do segmento condilar e um parafuso longo (11 mm) foi inserido, deixando uma parte (6 mm) extra-ósseo. Um sulco foi feito na parte lateral do ramo mandibular para alocação da parte extra-óssea do parafuso. Após redução e estabilização do segmento condilar, uma miniplaca de 2.0 mm foi instalada por cima do parafuso deixando a cabeça do parafuso mais inferiormente para maximizar a retenção. O paciente teve uma recuperação pós-operatória rápida, e função a função mastigatória foi reestabelecida...

Mandibular condyle fractures are common and the best approach to treating them has been extensively discussed in the literature. There are basically two different approaches to treatment of condyle fractures: the functional method and the surgical method. In the case described here, the patient underwent general anesthesia for open reduction and internal fixation. After a submandibular approach to access the fracture site, a bur was used to make a perforation in the base of the condylar segment and a long screw (11 mm) was inserted in place leaving a portion protruding from the bone (6 mm). A groove was made in the lateral part of the mandibular ramus to accommodate the extra osseous portion of the screw. After reduction and stabilization of the condylar segment, a 2.0 mm miniplate was installed over the screw leaving the screw head in an inferior position to maximize retention. The patient enjoyed a rapid postoperative recovery and early jaw function was restored in a short period of time...

Fiber-enriched calcium phosphate cement implanted in the femur of rats: a histological evaluation / Cimento de fosfato de cálcio reforçado por fibras implantados nos fêmures de ratos: uma avaliação histológica

Objective: to perform a histological analysis of nylon, carbon, and polypropylene fiber-enriched calcium phosphate cement (CPC) for use as bone substitute in the femur or rats. Materials and method: Fiber-enriched CPC blocks (6-mm diameter, 2-mm thickness) were im-planted in the femur of 20 male Wistar rats. The ani-mals were euthanized at 30, 60, 90, and 120 days, with removal and histological assessment of specimens. Results: Biocompatibility, resorption, and osteoconduc-tion were assessed. At all times, histological assessment revealed the formation of dense connective tissue with low cellularity, little vascularization, and a few mono-nuclear cells. Surrounding the implant, slight resorption and hyalinization of peripheral collagen fibers were ob-served, with evidence of incorporation of implant mate-rial into connective tissue. Osteoid tissue was observed at 120 days. Bone resorption surrounding the implant was not significant. Conclusion: Based on the present criteria, CPC seems adequate for use as bone substitute.

Analysis of the repair of bone defects filled with ß-tricalcium phosphate associated to pure titanium implants / Análise do reparo de defeitos ósseos preenchidos com ß-Tricálcio Fosfato associado a implantes de titânio

Objective: The present study aims to develop a histolo-gical descriptive analysis on the repair of bone defects filled with ?-TCP, associated to pure titanium implants into cavities prepared in the calvarial bone of rats. Ma-terials and method: Eighteen male adult rats were ran-domly selected and divided into three groups of six rats each, according to their period of death: 15, 30, and 60 days. Four bone defects were made into each one of the calvarial bones of rats and filled with: (a) ?-TCP, (b) clot, (c) ?-TCP + pure titanium screw, and (d) pure titanium screw. The samples were cut and histologically assessed. Presence and volume of loose connective tis-sue and newly formed bone tissue were analyzed, as well as the presence or absence of remaining material (?-TCP) into the defect. Results: It was verified an acce-leration bone neoformation process in the presence of ?-TCP. Conclusion: The results suggest the biocompa-tibility and osteoconductivity of the biomaterial, even when associated to pure titanium implants.

Histologic and biomechanical evaluation of 2 resorbable-blasting media implant surfaces at early implantation times.

This study evaluated 3 implant surfaces in a dog model: (1) resorbable-blasting media + acid-etched (RBMa), alumina-blasting + acid-etching (AB/AE), and AB/AE + RBMa (hybrid). All of the surfaces were minimally rough, and Ca and P were present for the RBMa and hybrid surfaces. Following 2 weeks in vivo, no significant differences were observed for torque, bone-to-implant contact, and bone-area fraction occupied measurements. Newly formed woven bone was observed in proximity with all surfaces.

Maxillary osteoradionecrosis - review of published literature: incidence, classification, risk factors, physiopathology and prevention / Osteorradionecrose dos maxilares - revisão da bibliografia publicada: incidência, classificação, fatores de risco, fisiopatologia e prevenção

Introduction: osteoradionecrosis (ORN) of facial bones is a serious complication of radiotherapy. Objective: this literature review was performed to study maxillary osteoradionecrosis, its incidence, classification, risk factors, physiopathology, prevention, and current treatment. Literature review: literature search using Medline was performed for all relevant articles with specific keywords from January 2000 to November 2011 aiming to find current data available on ORN and the paradigm change in physiopathology and prevention of the disease. The literature reviewed showed lack of either controlled or randomized trials, a few prospective studies, and a great amount of retrospective studies. Final considerations: adjunctive hyperbaric oxygen (HBO) therapy may be applied for osteoradionecrosis prevention, before and after dental procedures, with satisfying results. Nonetheless, several studies indicated that HBO therapy is not beneficial.

Isotretinoin effect on the repair of bone defects - a study in rat calvaria.

BACKGROUND: Isotretinoin is a vitamin A derivative, indicated for the treatment of patients with severe acne, which shows several side effects on bone metabolism. OBJECTIVE: This study analyzed the process of bone repair in rats receiving 7.5 mg/kg/day of oral isotretinoin. METHODS: Thirty-three male albino Wistar rats, at approximately 60 days of age, were randomly assigned to control (n = 15) and experimental (n = 18) groups. Only the experimental group underwent oral isotretinoin therapy. In both groups, a 2-mm cavity was established in the calvarium of each animal. The animals were euthanize 21, 28 and 90 days postoperatively. The parietal bone was removed and the surgical specimens underwent histological examination. Computed histomorphometry allowed the measurement of the total area of bone defects and the proportion of newly formed bone at the different observation time points. RESULTS: In the experimental group, the results, expressed as mean percentage of newly formed bone, were: 25.37% (±9.14) at day 21; 41.78% (±7.00) at day 28; and 57.51% (±11.62) at day 90. In the control group, the results were: 17.10% (±9.23) at day 21; 34.42% (±7.70) at day 28; and 48.49% (±16.40) at day 90. CONCLUSION: These results enabled us to conclude that isotretinoin promoted acceleration in the process of new bone formation in rat calvaria, although this increase was not statistically significant.

Angina bullosa haemorrhagica (ABH): diagnosis and treatment / Angina bolhosa hemorrágica (ABH): diagnóstico e tratamento

Angina bullosa hemorrhagica is a disorder of unknown etiology characterized by the sudden onset of blood blisters in the oral and oropharyngeal mucosa. Objective: The present study describes six cases of patients diagnosed with ABH affecting the soft palate and tongue. Lesions appeared after meals, suggesting mastication trauma as the probable causative factor. From six, 04 occurred in the soft palate and 02 in the tongue, showing firstly a bubble blood, and subsequently to its rupture, the appearing of an ulcer. Final consideration: The authors discuss diagnostic criteria, essentially based on clinical data, as well as possible treatment approaches.

Protocolo de tratamento em fraturas orbitárias / Treatment protocol for orbital fractures

Objetivo: Definir um protocolo de tratamento em fraturas orbitárias, comparando-o com as diversas formas de tratamento existentes na literatura atual. Metodologia: O protocolo proposto foi elaborado com base na experiência clínica adquirida por um cirurgião bucomaxilofacial junto a três hospitais em Porto Alegre - RS. Foram selecionados artigos de maior relevância sobre o assunto, discutindo diferentes formas de tratamento das fraturas orbitárias. Resultados: Após avaliação clínica e radiográfica, quando constatados lesões oculares ou neurológicas, os pacientes devem ser encaminhados ao oftalmologista e neurologista, respectivamente. Após o diagnóstico do cirurgião bucomaxilofacial, o tratamento deve ser realizado de acordo com a região anatômica orbitária envolvida. Conclusão: O estabelecimento de um protocolo num serviço de trauma de qualidade é de fundamental importância, visto que as fraturas orbitárias devem ser diagnosticadas com precisão e rapidez, visando a um tratamento adequado que minimize suas sequelas.

Assessment for treatment of tripod fractures of the zygoma with microcompressive screws.

PURPOSE: The present prospective study sought to evaluate a new rigid internal fixation device called a "neck screw," which was applied to patients presenting with a tripod fracture of the zygomaticomaxillary complex. PATIENTS AND METHODS: Seventeen patients with tripod fractures received surgical treatment from 2007 to 2010, and had their zygomaticomaxillary complex monofragments fixed using the neck screw protocol. The adequacy of fracture reduction, stability of the zygomatic monofragment after fixation, cosmetic outcomes, and postoperative complications were used to determine the efficacy of this protocol. The stability provided by the neck screw was evaluated by computed tomography (CT) scans by comparing the immediate postoperative distances between the fractured bone segments (control group) with those distances measured on CT scans obtained 5 weeks later (late group). RESULTS: The average distance observed between the fractured ends on the immediate postoperative CT scan was less than 0.58 mm, demonstrating adequate fracture reduction. No significant changes were seen in these postoperative values after 5 weeks (Wilcoxon test, P = 1.0000), demonstrating no displacement of the zygomaticomaxillary complex monofragment after fixation using the neck screw. CONCLUSIONS: The proposed surgical treatment proved efficient in 17 patients. The fixation stability provided by the neck screw was confirmed by subsequent CT scan measurements, statistical analysis, and clinical follow-up during the postoperative period, in which patients showed no significant associated complications, facial asymmetry, enophthalmos, or diplopia.

Oral myiasis.

Human myiasis results from parasitic tissue infestation by maggots. It often develops in open or necrotic wounds and has its highest prevalence among poor populations in tropical regions. This study reports 2 cases of human myiasis in the oral cavity and describes its clinical aspect and treatment.