Retraction: Bacterial adhesion and colonization differences between zirconia and titanium implant abutments: an in vivo human study.

[This retracts the article on p. 217 in vol. 42, PMID: 23346465.].

Comparative evaluation of different fixation techniques of the sagittal split ramus osteotomy in 10 mm advancements: Mechanical testing and screw insertion torque.

PURPOSE: To compare the mechanical characteristics of five techniques for the functionally stable fixation of simulated sagittal split ramus osteotomy with 10 mm of advancement and to evaluate the screw insertion torque. MATERIALS AND METHODS: Fifty polyurethane hemimandibles with sagittal split ramus osteotomy and containing an advancement of 10 mm fixed and distributed as follows: Customized 3D Plate Group: 1 customized 3D miniplate; 4-Hole Plate Group: 2 miniplates with 4 holes; 6-Hole Plate Group: 2 miniplates with 6 holes; Hybrid Group: 1 flat miniplate with 4 holes and 1 bicortical screw; and Bicortical Screw Group: 3 bicortical screws. We conducted a mechanical test using vertical linear loading with a displacement velocity of 1 mm/min on a universal testing machine and assessed the screw insertion torque using a digital torque wrench. RESULTS: The means of strength for the 1-, 3- and 5-mm displacements were determined by a one-way analysis of variance (ANOVA) followed by the post hoc Tukey test. Statistically significant differences were observed only for the 5-mm displacement (F = 3.36; p = 0.01). There was a difference between the 4-H2P and HG groups (p = 0.04). CONCLUSION: The customized miniplate, the fixation methods with three bicortical screws, or with two straight miniplates with either 4 or 6 holes, all offer a similar mechanical resistance suitable for fixation.

Retention and Mechanical Behavior of Attachment Systems for Implant-Retained Auricular Prostheses.

OBJECTIVE: Auricular prostheses are artificial substitutes for facial defects. The retention of these has often been a problem. This study aimed to evaluate the mechanical behavior of 3 retained auricular prosthetic connections when submitted to a mechanical cycling test. MATERIALS AND METHODS: Twelve samples with installed implants were obtained and divided into 3 groups according to their retention system with 4 samples in each group. I: bar-clip system; II: magnet system; and III: ball/o-ring system. Each of samples was submitted to the pull-out test during 3240 cycles (f = 0.5 Hz) to determine its tensile strength. The mechanical cycling test was performed using the servo-hydraulic machine MTS 810-Flex Test 40 (Eden Prairie, MN) that had a 2.5 mm shift at a 10 mm/s velocity. The retaining strength for each of the samples was obtained at 7 intervals. RESULTS: The tensile strength for the group retained by the bar-clip system (29.60 N) was higher with statistically significant difference (P < 0.05) when compared with the group retained by the ball/o-ring system (9.41 N) and magnets system (8.61 N) for all periods assessed. The ball/o-ring system showed loss of retention during the fatigue test (Kruskal-Wallis, chi-squared = 17.28; P < 0.01). CONCLUSIONS: The evaluated systems showed a tensile strength compatible with the clinical use and no fractures of the components were observed.

Stability of the prosthetic screws of three types of craniofacial prostheses retention systems.

OBJECTIVES: This study aimed to evaluate the stability of prosthetic screws from three types of craniofacial prostheses retention systems (bar-clip, ball/O-ring, and magnet) when submitted to mechanical cycling. MATERIALS AND METHODS: Twelve models of acrylic resin were used with implants placed 20 mm from each other and separated into three groups: (1) bar-clip (Sistema INP, São Paulo, Brazil), (2) ball/O-ring (Sistema INP), and (3) magnet (Metalmag, São Paulo, Brazil), with four samples in each group. Each sample underwent a mechanical cycling removal and insertion test (f=0.5 Hz) to determine the torque and the detorque values of the retention screws. A servo-hydraulic MTS machine (810-Flextest 40; MTS Systems, Eden Prairie, MN, USA) was used to perform the cycling with 2.5 mm and a displacement of 10 mm/s. The screws of the retention systems received an initial torque of 30 Ncm and the torque values required for loosening the screw values were obtained in three cycles (1,080, 2,160, and 3,240). The screws were retorqued to 30 Ncm before each new cycle. RESULTS: The sample was composed of 24 screws grouped as follows: bar-clip (n=8), ball/O-ring (n=8), and magnet (n=8). There were significant differences between the groups, with greater detorque values observed in the ball/O-ring group when compared to the bar-clip and magnet groups for the first cycle. However, the detorque value was greater in the bar-clip group for the second cycle. CONCLUSION: The results of this study indicate that all prosthetic screws will loosen slightly after an initial tightening torque, also the bar-clip retention system demonstrated greater loosening of the screws when compared with ball/O-ring and magnet retention systems.

Accuracy in the Diagnosis of the Mental Nerve Loop. A Comparative Study Between Panoramic Radiography and Cone Beam Computed Tomography.

Dental implant and chin osteotomy are executed on the mandible body and the mental nerve is an important anatomical limit. The aim of this research was to know the position of the mental nerve loop comparing result in panoramic radiography and cone beam computed tomography. We analyzed 94 hemimandibles and the patient sample comprised female and male subjects of ages ranging from 18 to 52 years (mean age, 35 years) selected randomly from the database of patients at the Division of Oral Radiology at Piracicaba Dental School State University of Campinas; the anterior loop (AL) of the mental nerve was evaluated regarding the presence or absence, which was classified as rectilinear or curvilinear and measurement of its length was obtained. The observations were made in the digital panoramic radiography (PR) and the cone beam computed tomography (CBCT) according to a routine technique. The frequencies of the AL identified through PR and CBCT were different: in PR the loop was identified in 42.6% of cases, and only 12.8% were bilateral. In contrast, the AL was detected in 29.8% of the samples using CBCT, with 6.4% being bilateral; Statistical comparison between PR and CBCT showed that the PR led to false-positive diagnosis of the AL in this sample. According to the results of this study, the frequency of AL is low. Thus, it can be assumed that it is not a common condition in this population.

8-10 year follow-up survival of dental implants in maxillae with or without autogenous bone graft reconstruction.

The aim of this research was to ascertain the survival of implants installed in the atrophic maxillae of patients treated with or without autogenous bone graft at 8 to 10 years of follow-up. A retrospective study was conducted using clinical and imaging analysis. 42 adult patients were selected, treated with osseointegrated implants in a fixed maxillary prosthesis model with suprastructure using 6 to 8 implants; of these, 22 underwent reconstruction with a bone graft taken from the anterior iliac crest and 20 were treated without any type of bone graft. The sequence of removal, installation and management of the grafts followed routine patterns, and the implant installation and prosthesis preparation also followed parameters established in previous publications. Variables of implant survival, stage of loss and bone stability of the implants were analyzed with the Wilcoxon signed-rank test, considering a value of P<0.05 to obtain statistical significance. After 8 to 10 years of follow-up the 306 implants installed in the 42 patients were evaluated. 162 implants were in the bone graft group, where 8.0% of implants were lost in the pre-loading stage, 3.7% in the post-loading stage and 88.7% had complete survival. In the group without bone graft, 6.17% were lost in the pre-loading stage, 1.85% in the post-loading stage and 90.97% had complete survival. There was no significant difference in the survival of the implants between the two groups (P=0.082). Cervical bone loss between the groups showed no significant differences either (P=0.241). The implants in grafted maxillae with cases of severe maxillary atrophy are just as efficient as implants installed in maxillae without bone graft.

Photoelastic analysis of fixed partial prosthesis crown height and implant length on distribution of stress in two dental implant systems.

The aim of this study was to evaluate by photoelastic analysis stress distribution on short and long implants of two dental implant systems with 2-unit implant-supported fixed partial prostheses of 8 mm and 13 mm heights. Sixteen photoelastic models were divided into 4 groups: I: long implant (5 × 11 mm) (Neodent), II: long implant (5 × 11 mm) (Bicon), III: short implant (5 × 6 mm) (Neodent), and IV: short implants (5 × 6 mm) (Bicon). The models were positioned in a circular polariscope associated with a cell load and static axial (0.5 Kgf) and nonaxial load (15°, 0.5 Kgf) were applied to each group for both prosthetic crown heights. Three-way ANOVA was used to compare the factors implant length, crown height, and implant system (α = 0.05). The results showed that implant length was a statistically significant factor for both axial and nonaxial loading. The 13 mm prosthetic crown did not result in statistically significant differences in stress distribution between the implant systems and implant lengths studied, regardless of load type (P > 0.05). It can be concluded that short implants showed higher stress levels than long implants. Implant system and length was not relevant factors when prosthetic crown height were increased.

Photoelastic evaluation of two different sagittal split ramus osteotomies in advancement surgery.

The aim of this study was to establish the influence of the design of the sagittal split ramus osteotomy (SSRO) on stress distribution on the osteosynthesis in a photoelastic resin model. Two polyurethane hemimandibles were used to perform the osteotomies, tilted in the lateral sector of the first/second molar (group I) and the other descending downwards and laterally from the first molar (group II), with no higher angle. Six replicas of each were made in photoelastic resin and stabilized with a plate and 5 mm monocortical screws in a standardized way. Stabilization was done in the SSRO without advancement, with 3 mm advancement and with 7 mm advancement. Compressive loads were applied at the level of the lower first molar in an Instron machine (model 4411) with a speed of 1 mm/min until reaching 3 mm of displacement, at which point the data was recorded with a camera to identify the stress distribution bands. The results showed stress distribution in different places: for group I it was observed mainly in the screws of the proximal segment, being more intense closer to the osteotomy; in group II I it was observed mainly in the screws of the proximal segment furthest from the osteotomy, also being distributed towards the upper area of the plate. It may be concluded that under standard osteosynthesis conditions, modifications to the SSRO produce changes in the location and distribution of stress.

Bisphosphonate-related osteonecrosis of the jaw: a review of the literature.

Bisphosphonates (BPs) are a class of drugs used to treat osteoporosis and malignant bone metastasis. BPs show high binding capacity to the bone matrix, especially in sites of active bone metabolism. The American Society for Bone and Mineral Research defines BRONJ as "an area of exposed bone in the maxillofacial region that has not healed within 8 weeks after identification by a healthcare provider in a patient who is receiving or has been exposed to a bisphosphonate and has not had radiation therapy to the craniofacial region." Bisphosphonate-related osteonecrosis of the jaw (BRONJ) can adversely affect quality of life, as it may produce significant morbidity. The American Association of Oral and Maxillofacial Surgeons (AAOMS) considers as vitally important that information on BRONJ be disseminated to other dental and medical specialties. The purpose of this work is to offer a perspective on how dentists should manage patients on BPs, to show the benefits of accurately diagnosing BRONJ, and to present diagnostic aids and treatments strategies for the condition.

Facial and cervical emphysema after oral surgery: a rare case.

The purpose is to report extensive emphysema resulting from a common procedure in oral surgery. Surgical emphysema developed in a 23-year-old female after removal of a mandible third molar using a high-speed dental hand-piece. The patient was maintained in hospital room and submitted to a medical protocol with antibiotic treatment. Surgical emphysema is an uncommon but potentially serious complication of oral and maxillofacial surgery procedures. The diagnosis and differential diagnosis of surgical emphysema are discussed and the management and prevention of this complication is presented. Adequately treatment with adequately instrument should be providing in oral surgery. Emphysema has complication in oral surgery is a rare condition with future clinical and legal problem to surgeon.

Maxillary sinus floor augmentation using blood without graft material. Preliminary results in 10 patients.

PURPOSE: The maxillary sinus lift is recognized and stable, and there have been different innovations to optimize the technique. The aim of this study was to investigate the maxillary sinus lift technique with the use of a blood clot and without the use of a bone graft. MATERIALS AND METHODS: Ten patients were recruited for a unilateral sinus lift; patients without sinus pathology or other contraindication were selected. The maxillary sinus was accessed conventionally under local anesthesia followed by an osteotomy and a 1-cm(2) bony window access. The sinus membrane was detached and the window was repositioned above and stabilized with a 12- or 14-mm osteosynthesis screw introduced through the alveolar ridge. Dental implants were installed in the second surgical stage. Standardized panoramic radiographic checks were performed at every stage. RESULTS: Seven completely edentulous patients and 3 partially dentate patients were treated surgically. From the first to the second surgery, a bone gain of 2.37 mm was obtained, although loss of bone height was observed in 1 completely edentulous patient. In 7 patients, it was not possible to install the implants owing to insufficient bone height or inadequate bone quality. CONCLUSION: The protocol used in this investigation failed in the bone increase required for implant installation.

Implantes extrabucales para la rehabilitación craneofacial / Extraoral fixation for craniofacial rehabilitation

Las prótesis maxilofaciales retenidas en implantes extrabucales o fijaciones cr neofaciales son herramientas claves en la rehabilitaci¢n de pacientes con alteraciones faciales debido a resecciones asociada con enfermedades, traumas graves, malformaciones y otros. El uso de implantes craneofaciales se caracteriza, principalmente, por ser procedimientos quir£rgicos r pidos, efectuados con anestesia general o local, con poca morbilidad y gran versatilidad para tratar diferentes  reas cr neofaciales como la regi¢n orbitaria, auricular y nasal, entre otras. Sin embargo, a£n existen dudas respecto a los protocolos e indicaciones de tratamientos asi como en otros t¢picos de relevancia. La siguiente revisi¢n bibliogr fica tiene como objetivo recolectar la informaci¢n cient¡fica disponible respecto de las fijaciones cr neofaciales abordando diferentes elementos de la evoluci¢n y procedimientos quir£rgicos para la instalaci¢n de estos dispositivos.

Maxillofacial prosthesis retained in extraoral implants or craneofacial attachments are key tools in the rehabilitation of patients withfacial abnormalities due to associated diseases, severe trauma, malformations and others. The use of craniofacial implants is mainlycharacterized by rapid surgical procedures performed under general or local anesthesia, with little morbidity and versatility to treatdifferent facial skull and the orbital region, auricular, nasal, among other areas. However, there are still doubts about protocols andtreatment indications as well as other relevant topics. The aim of this literature review was to collect the scientific information availablerelated to craniofacial fixations addressing different elements of evolution and surgical procedures for the installation of these devices.

Morphometric study of mandibular ramus related to sagittal ramus split osteotomy and osteosynthesis.

The objective of this study was to quantify the cortical bone thickness of the mandibular ramus to determine conditions related to sagittal split ramus osteotomy and placement of screws. The patient sample comprised 44 subjects of ages ranging from 46 to 52 years (mean age, 49 years). The cone-beam computed tomography was performed and realized 3 cuts in the third molar area (section A), 5 mm posterior (section B), and 5 mm posterior to the latter (section C). Measurement in the cortical areas of the superior and inferior levels related to mandibular canal and measurement related to the total width of the mandible was executed. Intraclass correlation coefficient with P < 0.05 was used. The result showed that the buccal and lingual cortical zone did not present statistical differences, and the minor value was 1.5 mm for each one. There were no differences in the superior and inferior cortical bone, and the total width of the mandible was between 15.9 and 8.5 mm in the anterior area, between 17.4 and 12.8 mm in the middle area, and between 18 and 8.8 mm in the posterior area. The distance superiorly to the mandibular canal presented a minimal SD with a mean of 8.5 mm in the anterior region, 10.6 mm for the middle region, and 12.5 mm in the posterior region. In conclusion, the cortical thickness of the mandibular ramus in the adult population is particularly strong and offers a good anchorage for screw insertion in sagittal split ramus osteotomy.

Bacterial adhesion and colonization differences between zirconia and titanium implant abutments: an in vivo human study.

PURPOSE: Several parameters have been described for determining the success or failure of dental implants. The surface properties of transgingival implant components have had a great impact on the long-term success of dental implants. The purpose of this study was to compare the tendency of two periodontal pathogens to adhere to and colonize zirconia abutments and titanium alloys both in hard surfaces and soft tissues. METHODS: Twelve patients participated in this study. Three months after implant placement, the abutments were connected. Five weeks following the abutment connections, the abutments were removed, probing depth measurements were recorded, and gingival biopsies were performed. The abutments and gingival biopsies taken from the buccal gingiva were analyzed using real-time polymerase chain reaction to compare the DNA copy numbers of Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, and total bacteria. The surface free energy of the abutments was calculated using the sessile water drop method before replacement. Data analyses used the Mann Whitney U-test, and P-values below 0.05 find statistical significance. RESULTS: The present study showed no statistically significant differences between the DNA copy numbers of A. actinomycetemcomitans, P. gingivalis, and total bacteria for both the titanium and zirconia abutments and the biopsies taken from their buccal gingiva. The differences between the free surface energy of the abutments had no influence on the microbiological findings. CONCLUSIONS: Zirconia surfaces have comparable properties to titanium alloy surfaces and may be suitable and safe materials for the long-term success of dental implants.

Pattern and treatment of facial trauma in pediatric and adolescent patients.

Pediatric maxillofacial trauma is a challenge for surgeons. There are no completely defined protocols, and sometimes, the initial management could be complex. The aim of this research was to perform a retrospective study to analyze the pattern and treatment of maxillofacial fractures in pediatric and adolescent patients. We reviewed the clinical records of 2986 patients treated at the Oral and Maxillofacial Surgery Division of Piracicaba Dental School between 1999 and 2008. Seven hundred fifty-seven patients were younger than 18 years and were divided into 3 groups according to age; the age and sex of the patients, etiology, fractures and associated injury, treatment, and complications were evaluated. Five hundred thirty boys (70.01%) and 227 girls (29.99%) were treated for injuries with major prevalence in adolescents. The most common injury causes were bicycle accidents (29.06%) and falls (28.40%). The mandible was the most fractured bone (44.8%); associated injuries were lacerations of the soft tissue and dental trauma. Surgical treatment was performed in 75 cases (30%) with minor complications (10% of surgical patients). We conclude that maxillofacial trauma in child is associated to fall and bicycle accidents; the mandible is more affected than other maxillofacial structures, and frequently, nonsurgical treatment is performed.

Mineralized tissue formation associated with 2 different dental implant designs: histomorphometric analyses performed in dogs.

The clinical success of dental implants might be associated with such factors as installation technique, implant shape, size, material, and screw threads. Therefore, the aim of this study is to analyze mineralized tissue formation on the screw threads of conical and cylindrical dental implants. This study includes 7 beagle dogs that had the lower premolars extracted. Three months after bone and soft tissue repair, 2 different designs of dental implants (1 conical and 1 cylindrical) were installed in each hemimandible using a nonsubmerged technique. Both implants when installed had different shape and thread, as revealed by scanning electron microscopy. Six weeks after implant installation, animals were killed and submitted to histomorphometric analysis. Cervical, middle, and apical areas were analyzed. Statistical analysis was carried out using Student t test at a significance level of P < .05. Statistically significant differences were not found between the conical and cylindrical implants. The conical implants presented fewer threads, a smaller area, and more bone formation when compared with the cylindrical ones, without significant differences (P  =  .1226). The highest values concerning bone formation were observed for the cervical area (P  =  .4005), and the lowest for the apical area (P  =  .1899); however, no statistically significant difference was observed. In conclusion, no statistically significant difference was observed in thread bone formation between the cylindrical and conical implant designs when placed using the nonsubmerged technique.

Tratamiento quirúrgico de Fracturas mandibulares en pacientes pediátricos: Revisión Bibliográfica / Surgical treatment of mandibular fractures in pediatric patients

Las fracturas faciales en niños muestran características importantes en lo que respecta a su prevalencia, diagnóstico y tratamiento, las cuales las diferencian de las fracturas en adultos. Por estas razones, el trauma infantil debe ser objeto de especial atención ya que presentan particulares características anatómicas, fisiológicas y psicológicas propias de la edad del paciente. Las fracturas mandibulares infantiles que presenten pequeños desplazamientos pueden ser tratadas conservadoramente, mientras que, aquellas que presenten desplazamientos mayores y que interfieran con la función deben ser tratadas de manera semejante a la de los adultos, esto es con reducción cruenta y estabilización, la misma que puede ser obtenida por medio de dispositivos como placas, alambres de acero, tornillos, tornillos y placas de titanio o mediante sistemas de osteosíntesis resorbibles. Estos diferentes sistemas presentan indicaciones, ventajas y desventajas, las cuales deben ser consideradas a fin de elegir la opción de tratamiento más adecuada.

The facial fractures in children show important characteristics about their prevalence, diagnosis and treatment, which differentiate them from fractures in adults. For these reasons, children trauma should be a subject of special attention to due the anatomical, physiological and psychological considerations of the patient´s age. The children jaw fractures that show little displacements can be treat in a conservative way, while those that show greater displacements and interfering with the function should be treated similarly to that in adults, this is with open reduction and stabilization, using some devices such as plaques, steel wires, screws and titanium plaques or through resorbable osteosynthesis systems. These different systems show indications, advantages and disadvantages, which must be considered in order to choose the most suitable treatment.

Inflammatory fibrous hyperplasia treated with a modified vestibuloplasty: a case report.

AIM: The purpose of this report is to present a case of surgical and prosthetic treatment of a woman with inflammatory fibrous hyperplasia (IFH) and her evaluation during a six month period. BACKGROUND: IFH is a benign pathology, prevalent in female patients, and principally associated with ill-fitting prosthetic devices in need of adjustment. It is common for patients to require surgical removal of the hyperplastic tissue and fabrication of a new prosthesis. CASE REPORT: A 55-year-old female with a history of smoking presented with a chief complaint of missing the scheduled adjustment of her maxillary complete denture and the presence of moveable tissue under the denture. Surgical excision of the hyperplastic tissue followed with fixation of the prosthesis for six months to guide the healing of the soft tissue and to reshape the contours of the maxillary supporting tissues. SUMMARY: Surgical removal of hyperplasic soft tissue is a routine procedure, and the fixation of the prosthesis for the support of tissue during healing improves intraoral conditions for the fabrication of a new prosthesis in the future.

Complicaciones en las prótesis sobre implantes / Complications in implant-supported dentures

El propósito de esta revisión fue verificar las tasas de éxito y fallas, y las causas más frecuentes de complicaciones, tanto en las prótesis soportadas por implantes como en los implantes propiamente dichos. Se puede notar un mayor número de complicaciones en las fijaciones de los maxilares superiores, comparados con los inferiores. Las fracturas de la superestructura metálica y/o dientes artificiales, fractura o inclinación de los pilares, fractura de la estructura metálica y fractura de los clips retentivos (sobredentaduras) fueron los problemas más comunmente encontrados. Se verificó que pacientes desdentados presentando rebordes severamente reabsorbidos pueden conseguir un buen pronóstico con prótesis implantosoportadas, eliminando la inestabilidad de las prótesis. El grado de satisfacción de los pacientes fue alto, y la tasa de pérdida de los implantes fue baja. Los problemas periodontales de mayor incidencia fueron presencia de placa, infecciones y pequeñas bolsas en torno de las fijaciones. Se verificó que las prótesis sobre implantes oseointegrados presentan ventajas y desventajas, como cualquier otro modelo restaurador; sin embargo, al ser comparadas con las prótesis totales y removibles convencionales, pueden ofrecer mayor seguridad a los pacientes debido a su mayor estabilidad.

Complicaciones en las prótesis sobre implantes / Complications in implant-supported dentures

El propósito de esta revisión fue verificar las tasas de éxito y fallas, y las causas más frecuentes de complicaciones, tanto en las prótesis soportadas por implantes como en los implantes propiamente dichos. Se puede notar un mayor número de complicaciones en las fijaciones de los maxilares superiores, comparados con los inferiores. Las fracturas de la superestructura metálica y/o dientes artificiales, fractura o inclinación de los pilares, fractura de la estructura metálica y fractura de los clips retentivos (sobredentaduras) fueron los problemas más comunmente encontrados. Se verificó que pacientes desdentados presentando rebordes severamente reabsorbidos pueden conseguir un buen pronóstico con prótesis implantosoportadas, eliminando la inestabilidad de las prótesis. El grado de satisfacción de los pacientes fue alto, y la tasa de pérdida de los implantes fue baja. Los problemas periodontales de mayor incidencia fueron presencia de placa, infecciones y pequeñas bolsas en torno de las fijaciones. Se verificó que las prótesis sobre implantes oseointegrados presentan ventajas y desventajas, como cualquier otro modelo restaurador; sin embargo, al ser comparadas con las prótesis totales y removibles convencionales, pueden ofrecer mayor seguridad a los pacientes debido a su mayor estabilidad. (AU)