Home About us Contact
|
Home About us Contact | ||
|
|
||
Maxilla
Kinds of Maxilla Selected AbstractsEsthetic Restoration of the Traumatized and Surgically Reconstructed Anterior MaxillaJOURNAL OF ESTHETIC AND RESTORATIVE DENTISTRY, Issue 5 2002DGDP(UK), PAUL A. TIPTON BDS ABSTRACT: A car accident victim can lose not only anterior teeth but also the soft- and hard-tissue support for these teeth. This article describes a step-by-step approach to the treatment protocol for an accident victim in whom anterior teeth and the supporting tissues have been lost. The protocol is systematic and can be used for most accident cases, where the functional and esthetic demands are very high. CLINICAL SIGNIFICANCE: This article demonstrates how excellent teamwork among the dentist, implant surgeon, and laboratory technician can result in a well-conceived and successful restoration following traumatic injury of the dentition. [source] The Milled Bar-Retained Removable Bridge Implant-Supported Prosthesis: A Treatment Alternative for the Edentulous MaxillaJOURNAL OF ESTHETIC AND RESTORATIVE DENTISTRY, Issue 4 2002DGDP(UK), PAUL A. TIPTON BDS ABSTRACT Restoration of the edentulous jaw with dental implants can be achieved using either an implant-supported prosthesis, such as a fixed bridge, or an implant-retained prosthesis, such as a traditional overdenture. The implant-retained prostheses use edentulous ridges as primary stress-bearing regions, and through stress-breaking mechanisms, the implants are not loaded during function. However, the success rates of maxillary overdentures do not appear to be as good as for mandibular overdentures; this may be attributable to the adverse loading conditions, short implant length, poor quality of bone, number of implants used, flexible bar design, or poor treatment planning. Many articles have also described the numerous problems and multiple visits required in maintaining a traditional bar-retained overdenture restoration, often making it more expensive in the long term than a fixed restoration. The milled bar implant-supported prosthesis offers the benefits of both fixed and removable restorations. Its infrastructure provides the same rigidity as the fixed restoration, owing to the precise fit to the superstructure, which is removable, to promote adequate access for hygiene, yet it still provides lip support and maintains close contact with the soft tissues. These advantages enhance phonetics, esthetics, correct lip support, maintenance, and patient comfort. CLINICAL SIGNIFICANCE Restoring esthetics and function for the edentulous patient requires a multidiscipline approach for success. This article discusses the techniques for restoring function and esthetics for these patients, using a milled bar restoration supported and retained by dental implants. [source] Bone Remodeling in Maxilla, Mandible, and Femur of Young DogsTHE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 1 2008Sarandeep S. Huja Abstract Bone remodeling in the jaw is essential for metabolic needs, mechanical demands and for growth of the skeleton. Currently, there is no information on remodeling in the jaw of young dogs. Four ,5-month-old male dogs were given a pair of calcein bone labels. After killing, bone sections were obtained from the maxilla, mandible, and femur. The jaw specimens were obtained from regions associated with erupting permanent teeth. Undecalcified specimens were prepared for examination by histomorphometric methods to evaluate mineral apposition rate (,m/d), mineralizing surface/bone surface (%), and bone formation rate (BFR, %/yr) in the bone supporting erupting teeth and in the femurs. Only intracortical secondary osteonal remodeling units were measured. There were significant (P < 0.05) differences in the BFR for the three sites examined, with the highest BFR (72%/yr) being in the femur. The mandible had a BFR twofold greater than the maxilla (51%/yr vs. 25.5%/yr). The rate of turnover in the jaw and femur of young dogs is distinct from a similar comparison between the jaw and appendicular skeleton of adult (,1 yr old) dogs. Although BFR decreases with age in the femur, it remains elevated in the jaws. Anat Rec, 291:1,5, 2007. © 2007 Wiley-Liss, Inc. [source] Patterns of Innervation of the Anterior Maxilla: A Cadaver Study with Relevance to Canine Fossa Puncture of the Maxillary Sinus,THE LARYNGOSCOPE, Issue 10 2005Simon Robinson FRACS Abstract Objectives/Hypothesis: Complications from canine fossa puncture of the maxillary sinus are caused by damage to the anterior superior alveolar nerve (ASAN) and the middle superior alveolar nerve (MSAN). The aim of this study was to elucidate the pattern of ASAN and MSAN within the anterior maxilla and to secondly determine suitable surgical landmarks to aid in accurately localizing the area of the canine fossa least likely to produce complications when a trocar is passed into the maxillary sinus. Methods: Anatomic dissection of the anterior face of the maxilla from 20 cadaver heads was performed. The pattern and presence of the ASAN and MSAN was identified on each side and tabulated. Landmarks for the safest entry point for canine fossa puncture were determined, and each side had a puncture placed using these landmarks. Any disruption of nerves was noted. Results: Multiple differing patterns of ASAN were identified. The ASAN emerged from its foramen as a single trunk in 30 (75%) sides and in a double trunk in 10 (25%). In 24 (60%), single or multiple branches from the ASAN trunks were identified. A MSAN was identified in 9 (23%) maxillae. The safest entry point for a canine fossa puncture was where a vertical line drawn through the mid-pupillary line was bisected by a horizontal line drawn through the floor of the pyriform aperture. Conclusions: There is significant variation in the pattern of ASAN and MSAN within the anterior face of the maxilla. By using the newly described landmarks when performing a canine fossa puncture, there is reduced risk of damage to these nerves and provides a reliable point to enter the maxillary sinus. [source] Accuracy of Linear Measurement Provided by Cone Beam Computed Tomography to Assess Bone Quantity in the Posterior Maxilla: A Human Cadaver StudyCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 4 2008Sophie Veyre-Goulet DDS ABSTRACT Purpose: The aim of this study was to assess, for implant placement in the posterior maxilla, the accuracy of linear measurements provided by cone beam computed tomography (CBCT) using an image intensifier tube and television (TV) chain as an X-ray detector despite a loss of contrast resolution. The NewTom® 9000 (Quantitative Radiology, Verona, Italy) was used to explore the posterior maxilla. Materials and Methods: Fourteen measurements were taken in three dry maxillaries. On every anatomical site, three fiducial markers were placed on the bony crest to define a plane. Dry maxillaries were submitted to CBCT imaging examination. The maxillaries were then sawn according to the previously defined planes, and bone height and width were assessed using a caliper. The same measurements were taken on images. Results: Clinical analysis demonstrated no difference between real measurements and image measurements. Conclusions: Although cadaver bone density may not correspond to the density of vital bone, this in vitro study indicates that CBCT images provided by technique using image intensifier tube and TV chain as an X-ray detector are reliable to define the bone volume of the posterior maxilla for the purpose of planning the implant axis. [source] Malignant Tumors of the Maxilla: Virtual Planning and Real-Time Rehabilitation with Custom-Made R-zygoma Fixtures and Carbon,Graphite Fiber-Reinforced Polymer ProsthesisCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 1 2008Karl Ekstrand LDS ABSTRACT Background: Oral cancer is a mutilating disease. Because of the expanding application of computer technology in medicine, new methods are constantly evolving. This project leads into a new technology in maxillofacial reconstructive therapy using a redesigned zygoma fixture. Purpose: Previous development experiences showed that the procedure was time-consuming and painful for the patients. Frequent episodes of sedation or general anesthetics were required and the rehabilitation is costly. The aim of our new treatment goal was to allow the patients to wake up after tumor surgery with a functional rehabilitation in place. Materials and Methods: Stereolithographic models were introduced to produce a model from the three-dimensional computed tomography (CT). A guide with the proposed resection was fabricated, and the real-time maxillectomy was performed. From the postoperative CT, a second stereolithographic model was manufactured and in addition, a stent for the optimal position of the implants. Customized zygoma implants were installed (R-zygoma, Integration AB, Göteborg, Sweden). A fixed construction was fabricated by using a new material based on poly(methylacrylate) reinforced with carbon/graphite fibers and attached to the implants. On the same master cast, a separate obturator was fabricated in permanent soft silicon. Results: The result of this project showed that it was possible to create a virtual plan preoperatively to apply during surgery in order for the patient to wake up functionally rehabilitated. Conclusion: From a quality-of-life perspective, it is an advantage to be rehabilitated fast. By using new computer technology, pain and discomfort are less and the total rehabilitation is faster, which in turn reduces days in hospital and thereby total costs. [source] A Prospective Clinical Study on Titanium Implants in the Zygomatic Arch for Prosthetic Rehabilitation of the Atrophic Edentulous Maxilla with a Follow-Up of 6 Months to 5 YearsCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 3 2006Carlos Aparicio DDS ABSTRACT Background, Prosthetic rehabilitation with implant-supported prostheses in the atrophic edentulous maxilla often requires a bone augmentation procedure to enable implant placement and integration. However, a rigid anchorage can also be achieved by using so-called zygomatic implants placed in the zygomatic arch in combination with regular implants placed in residual bone. Purpose, The aim of the present study was to report on the clinical outcome of using zygomatic and regular implants for prosthetic rehabilitation of the severely atrophic edentulous maxilla. Materials and Methods, Sixty-nine consecutive patients with severe maxillary atrophy were, during a 5-year period, treated with a total of 69 fixed full-arch prostheses anchored on 435 implants. Of these, 131 were zygomatic implants and 304 were regular implants. Fifty-seven bridges were screw-retained and 12 were cemented. The screw-retained bridges were removed at the examination appointments and each implant was tested for mobility. In addition, the zygomatic implants were subjected to Periotest® (Siemens AG, Bensheim, Germany) measurements. The patients had at the time of this report been followed for at least 6 months up to 5 years in loading. Results, Two regular implants failed during the study period giving a cumulative survival rate of 99.0%. None of the zygomatic implants was removed. All patients received and maintained a fixed full-arch bridge during the study. Periotest measurements of zygomatic implants showed a decreased Periotest values value with time, indictating an increased stability. Three patients presented with sinusitis 14,27 months postoperatively, which could be resolved with antibiotics. Loosening of the zygomatic implant gold screws was recorded in nine patients. Fracture of one gold screw as well as the prosthesis occurred twice in one patient. Fracture of anterior prosthetic teeth was experienced in four patients. Conclusions, The results from the present study show that the use of zygomatic and regular implants represents a predictable alternative to bone grafting in the rehabilitation of the atrophic edentulous maxilla. [source] Early Complete Failures of Fixed Implant-Supported Prostheses in the Edentulous Maxilla: A 3-Year Analysis of 17 Consecutive Cluster Failure PatientsCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 2 2006Odont Dr/PhD, Torsten Jemt DDS ABSTRACT Background, Clusters of implant failures in the edentulous maxilla seem to occur in some patients. To create groups for analysis with higher numbers of these patients implies large original groups for inclusion. Purpose, The aim of this study was to retrospectively describe and compare a group of "cluster failure patients" with randomly selected patients treated in the edentulous maxilla. Materials and Methods, From a group of 1,267 consecutively treated patients in one clinic, all patients presenting failing fixed implant-supported prostheses within the first 3 years of follow-up were included. All patients were treated with turned titanium implants using two-stage surgery. A control group of equal number of patients were created for comparison. Data on patients were retrospectively retrieved from their records, and compared. Results, Seventeen patients (1.3%) met the inclusion criteria in the entire group. The bone resorption index revealed less bone quantity in the study group (p < .05) during implant placement, but there was no difference regarding primary implant stability at first-stage surgery. The distribution of short and long implants showed relatively higher number of short implants in the study group (p < .05), and more patients had a presurgical discussion on the risk of implant failure prior to treatment in this group (p < .05). Only 5 out of 102 implants (4.9%) were lost before prosthesis placement as compared to 38 and 25 lost implants during the following two years in the study group. Smoking habits and signs of bone loss related to periodontitis in the lower dentition were more frequent in the study group, but did not reach a significant level (p > .05). Conclusion, The results indicate that bone quantity, reflected in fixture length, has a significant impact on increased implant failure risk. Other factors of interest as predictors for implant failures could be smoking habits and also possibly signs of periodontitis in the opposing dentition. [source] Single Implants and Buccal Bone Grafts in the Anterior Maxilla: Measurements of Buccal Crestal Contours in a 6-Year Prospective Clinical StudyCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 3 2005Odont Dr/PhD, Torsten Jemt DDS ABSTRACT Background: Patients provided with buccal bone grafts seem to lose a substantial part of the graft in the short term. Purpose: To measure long-term changes in buccal and proximal tissue volumes after local bone grafting and single implant treatment. Materials and Methods: Eight of 10 originally treated male patients were followed up for 6 years after treatment with buccal bone grafts in the central incisor region. After a healing time of 6 months, a two-stage implant surgery procedure was performed followed by single crown placement. Clinical photographs and impressions were taken prior to the surgical interventions and after crown placement and at first and fifth annual checkups. The photographs were analyzed with regard to papilla regeneration by means of a clinical papilla index. The models were used to measure the clinical length of teeth and tooth movements adjacent to the implants. Changes in buccal crest volume during the study period were measured by means of optical scanning of obtained study models. Results: Papillae volume increased significantly (p < .05) during the first year, thereafter showing a slow further increase during the 4 following years. Three of the patients (38%) presented small movements of their adjacent central incisor in a vertical or palatal direction of less than 1 mm during the follow-up period. All patients showed resorption during the first year after grafting (p < .01), in which three patients (38%) had lost basically all of increased volume at second surgery. After abutment or crown placement, all patients showed an increased volume (p < .01), followed by an average reduction during the first year, reaching a significant level in the apical part of the crest (p < .05). Thereafter, a relatively stable average situation was observed during the following 4 years, with individual variations, however. Conclusion: Local bone grafting seems to create sufficient bone volume for implant placement after 6 months, but individual variations in resorption pattern make the grafting procedure unpredictable for long-term prognosis. Instead, the abutment and the crown seem to play a more important role for building up and maintaining the buccal contour in the coronal part of the crest long term. [source] Short Implants in the Severely Resorbed Maxilla: A 2-Year Retrospective Clinical StudyCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 2005Franck Renouard DDS ABSTRACT Background: Although the predictability of endosseous dental implants is well documented, the restoration of the posterior region of the maxilla remains a challenge. The placement of short implants is one therapeutic option that reduces the need for augmentation therapy. Purpose: The purpose of this retrospective study was to assess the survival rates of 6 to 8.5 mm-long implants in the severely resorbed maxilla following a surgical protocol for optimized initial implant stability. Materials and Methods: The study included 85 patients with 96 short (6,8.5 mm) implants (Brånemark System®, Nobel Biocare AB, Göteborg, Sweden) supporting single-tooth and partial reconstructions. The implants had a machined (54) or an oxidized (TiUniteÔ, Nobel Biocare AB) (42) surface. A one-stage surgical protocol with delayed loading was used. The patients were followed for at least 2 years after loading (average follow-up period 37.6 months). The marginal bone resorption was assessed by radiographic readings. Results: Five implants were lost during the first 9 months, and four implants were lost to follow-up. The cumulative survival rate was 94.6%. Four of the failed implants had a machined surface, and one had an oxidized surface. The mean marginal bone resorption after 2 years in function was 0.44 ± 0.52 mm. Conclusion: This study demonstrates that the use of short implants maybe considered for prosthetic rehabilitation of the severely resorbed maxilla as an alternative to more complicated surgical techniques. [source] A Three-Year Follow-Up Report of a Comparative Study of ITI Dental Implants® and Brånemark System® Implants in the Treatment of the Partially Edentulous MaxillaCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 3 2004Per Åstrand DDS ABSTRACT Background: Many longitudinal studies of different implant systems have been published but few controlled randomized investigations have been reported. A 1-year report of a comparative study of ITI Dental Implant System® implants (Straumann AG, Waldenburg, Switzerland) and Brånemark System® implants (Nobel Biocare AB, Gothenburg, Sweden) has been published by the present authors. This paper is a 3-year follow-up of that randomized study. Purpose: The aim of the study was to compare the outcome of fixed partial prostheses supported by ITI or Branemark implants. The outcome was evaluated primarily in terms of survival rates and changes in marginal bone level. Material and Methods: The study group comprised 28 patients with anterior residual dentition in the maxilla. The patients were provided with two to four implants on each side of the dentition and were randomly allocated to Brånemark implants or ITI implants; 77 ITI implants and 73 Brånemark implants were inserted. After 6 months abutment connections were made to both ITI and Brånemark implants. All patients were provided with fked partial prostheses of gold-ceramic. The patients were followed up annually with clinical and radiographic examinations for 3 years. Results: Two Brånemark implants and two ITI implants were lost. The Brånemark implants were lost before loading whereas the ITI implants were lost because of periimplantitis. The survival rate for both groups was 97.3%. The mean marginal bone level of the Brånemark implants was situated 1.8 mm from the reference point at both the baseline and the 3-year examinations. The corresponding values for the ITI implants were 1.4 mm at baseline and 1.3 mm after 3 years. There was no significant difference between the implant systems with regard to bone level or bone level change. A steady state of the marginal bone level was calculated to have been reached after 3 years for 95.5% of the Brånemark implants and 87.1% of the ITI implants. Periimplantitis (infection including pus and bone loss) was observed with seven ITI implants but with none of the Brånemark implants. This difference was statistically significant. Conclusions: No statistically significant differences were found between the implants studied, except for the frequency of periimplantitis, which was higher for the ITI implants. The survival rates were high, and the marginal bone loss was small for both systems. [source] Teeth in a Day® for the Maxilla and Mandible: Case ReportCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 1 2003Thomas J. Balshi DOS ABSTRACT Background: A growing body of evidence indicates that successful osseointegration of dental implants can take place in the wake of immediate loading, providing that bone quality and quantity are adequate, and patients follow postsurgical instructions carefully. Purpose: The goal of this report is to demonstrate the efficient treatment protocol based on immediate loading for both the maxilla and mandible, including extraction site locations. Materials and Methods: Following extraction of the remaining anterior mandibular teeth, 18 Brånemark implants (Nobel Biocare AB, Gothenburg, Sweden), including two zygoma and two pterygoid implants, were installed in both arches in accordance with the Teeth in a Day protocol developed by the authors 9 years ago. This protocol uses an acrylic screw-retained prosthesis, with steel prosthetic copings embedded, supported by full-size Brånemark implants to prevent micromotion at the bone-to-implant interface. Results: Only 1 of the 18 immediately loaded implants failed to osseointegrate. Three years after completion of treatment, the patient reported functioning well with no complications. Conclusions: When appropriate subjects are selected, the Teeth in a Day protocol offers patients a number of significant advantages, including condensed treatment time, reduced postsurgical discomfort, and almost instantaneous improvement in speech and masticatory function, esthetics, and patient self-image. [source] Influence of preimplant surgical intervention and implant placement on bone wound healingCLINICAL ORAL IMPLANTS RESEARCH, Issue 5 2003Christer Slotte Abstract: The aims of the present investigation were to study (1) the influence of preimplant (4 weeks) surgical intervention and (2) the influence of the implant placement per se on bone density and mineralized bone,implant contact (BIC) at implant sites in the rabbit jawbone. The experiment was performed in the edentulous area of the maxillas of 16 adult rabbits. In eight rabbits, the alveolar bone on the left side (test) was surgically exposed and a groove was prepared in the bone crest. Trabecular bone and marrow tissue were removed, and a bioabsorbable barrier membrane was placed to cover the groove. The right side underwent no treatment and served as the control. Four weeks later, a screw-shaped titanium implant was placed transversally through the maxilla, penetrating both the test and the control areas. After another 4 weeks of healing, the animals were killed to obtain ground sections for histomorphometry. Untreated jaws from eight rabbits served as reference specimens. In the rabbits subjected to surgery, the areas (mm2) of both mineralized bone and marrow tissue were similar for test and control (4.9 ± 1.7 vs. 5.1 ± 2.2 and 6.3 ± 5.7 vs. 6.8 ± 5.7 for bone and marrow, respectively). The BIC (%) for all threads was significantly lower on the test side than on the control side (32.1 ± 27.7 vs. 47.7 ± 20.3). The bone density (%) of the total experimental area was similar for test and control (48.5 ± 12.1 vs. 46.5 ± 9.3), as was the bone density in the area within the implant thread valleys and their mirror areas (43.0 ± 13.9 vs. 41.3 ± 13.5, and 40.2 ± 11.0 vs. 40.3 ± 7.2 for thread area and mirror area, respectively). The bone density of the total experimental area in the untreated rabbits was 35.9 ± 5.2%. This value was significantly lower than the values in the total experimental areas (test and control) of the surgically treated rabbits. Similarly, the density of the reference area in the untreated rabbits was 25.4 ± 5.3%, which was also significantly lower than the bone density of the periimplant area of the surgically treated rabbits. We conclude that the surgical trauma caused by the placement of implants in the maxilla of rabbits significantly enhanced the bone density of the implant sites. Surgical intervention in the implant sites 4 weeks prior to the implant placements, however, did not further enhance bone density or BIC. Résumé Les buts de cette étude ont été d'étudier 1) l'influence d'une intervention chirurgicale préimplantaire (4 semaines) et 2) l'influence du placement de l'implant per se sur la densité osseuse et le contact implant-os minéralisé (BIC). Cette expérience a été effectuée dans la région édentée du maxillaire de seize lapins adultes. Chez huit lapins, l'os alvéolaire du côté gauche (test) était chirurgicalement exposé et une marque a été faite dans la crête osseuse. L'os trabéculaire et le tissu spongieux ont été enlevés et une membrane biorésorbable a été placée pour couvrir ce trou. Le côté droit ne subissait aucun traitement et a servi de contrôle. Quatre semaines après, un implant en titane vis a été placé transversalement à travers le maxillaire pénétrant tant la zone test que contrôle. Après quatre semaines de guérison les animaux ont été tués pour obtenir des coupes pour l'histomorphométrie. Les mâchoires non-traitées de huit lapins ont servi de spécimens de référence. Chez les lapins soumis à la chirugie les zones d'os minéralisé et de tissu spongieux étaient semblables pour le test et le contrôle (respectivement 4,9±1,7 mm2 vs 5,1±2,2 mm2 et 6,3±5,7 mm2 vs 6,8±5,7mm2). Les BIC pour tous les filetages étaient significativement moins importants au niveau des tests que des contrôles (32,1±27,7% vs 47,7±20,3%). La densité osseuse du total de l'aire expérimentale était semblable pour les tests et les contrôles (48,5±12,1%vs 46,3±9,3%) comme l'était la densité osseuse dans la zone à l'intérieur du filetage de l'implant et de leurs aires mineures (43,0±13,9%vs 41,3±13,5% pour les filetages et 40,2±11,0% vs40,3±7,2% pour les aires mineures). La densité osseuse de l'aire expérimentale totale chez les lapins nont-traités était de 35,9 ±5,2%. Cette valeur était significativement inférieure à celles dans les aires expérimentales totales (tests et contrôles) des lapins traités chirurgicalement. Parallèlement, la densité de l'aire de référence des lapins non-traités était de 25,4±5,3% c.-à-d. inférieure à la densité osseuse de la zone paroïmplantaire des lapins traités chirurgicalement. Le trauma chirurgical causé par le placement d'implants dans le maxillaire de lapins augmente significativement la densité osseuse au niveau des sites implantaires. L'intervention chirurgicale des sites à implanter quatre semaines avant le placement des implants n'avait cependant augmenté ni la densité osseuse ni le BIC. Zussammenfassung Der Einfluss eines praeimplantären chirurgischen Eingriffes und der Implantation per se auf die Heilung der Knochenwunde. Eine Studie am Kieferknochen des Kaninchens. Ziel: Das Ziel dieser Studie war es 1) den Einfluss eines praeimplantären chirurgischen Eingriffes (4 Wochen vorher) und 2) den Einfluss der Implantation per se auf die Knochendichte und den mineralisierten Knochen-Implantatkontakt (BIC) an einer Implantationsstelle im Kieferknochen des Kaninchens zu untersuchen. Material und Methode: Die Testregion war der zahnlose Oberkieferabschnitt von 16 ausgewachsenen Kaninchen. Bei 8 Kaninchen wurde der Alveolarknochen der linken Seite (Test) chirurgisch freigelegt und eine Vertiefungen in den Knochenkortex präpariert. Dann entfernte man den trabekulären Knochen und das Knochenmark und deckte die Vertiefung mit einer bioresorbierbaren Membran ab. Die rechte Seite wurde unbehandelt belassen und diente als Kontrolle. Vier Wochen später implantierte man ein schraubenförmiges Titanimplantat transversal durch die Maxilla, so dass es Test- oder Kontrollregion durchdrang. Nach einer Heilphase von weiteren vier Wochen wurden die Tiere geopfert und von der zu untersuchenden Region Grundschnitte für die Histologie hergestellt. Als Referenz dienten unbehandelte (jungfräuliche) Kiefer von weiteren 8 Kaninchen. Resultate: Bei den Kaninchen, welche die oben beschriebenen chirurgischen Schritte durchlaufen haben, waren sowohl bei der Test- wie auch bei der Kontrollgruppe die Fläche von mineralisiertem Knochen und Knochenmark (in mm2) ähnlich gross (4.9+1.7 gegenüber 5.1+2.2 beim Knochen und 6.3+5.7 gegenüber 6.8+5.7 beim Knochenmark). Der BIC (%) war in allen Schraubenwindungen auf der Testseite signifikant tiefer als auf der Kontrollseite (32.1+27.7 gegenüber 47.7+20.3). Die Knochendichte (%) war in der untersuchten Region bei der Test- und Kontrollseite etwa gleich gross (48.5+12.1 gegenüber 46.5+9.3) wie die Knochendichte in den Vertiefungen der Schraubenwindungen und ihrer spiegelbildlichen Regionen (43.0+13.9 gegenüber 41.3+13.5 in den Schraubenwindungen und 40.2+11.0 gegenüber 40.3+7.2 in den spiegelbildlichen Regionen). Die Knochendichte in der gesamten Region der unbehandelten (jungfräulichen) Kaninchen betrug 35.9+5.2%. Dieser Wert war signifikant tiefer als die Werte der gesamten untersuchten Region der chirurgisch behandelten Kaninchen (Test- und Kontrollseite). Ganz ähnlich war die Dichte in der Referenzregion der unbehandelten Kaninchen 25.4+5.3%, ein Wert der auch signifikant tiefer war als die Knochendichte in der periimplantären Region von chirurgisch behandelten Kaninchen. Zusammenfassung: Das chirurgische Trauma, das beim Setzen eines Implantates im Oberkiefer von Kaninchen entsteht, begünstigt die Knochendichte an den Stellen der Implantate signifikant. Der chirurgischen Eingriff vier Wochen vor der Implantation jedoch, förderte an den zur Implantation vorgesehenen Stellen weder Knochendichte noch BIC. Resumen Objetivos: La intención de la presente investigación fue estudiar 1) la influencia de la intervención quirúrgica (4 semanas) periimplantaria y 2) la influencia de la colocación de implantes per se en la densidad ósea y el contacto del hueso mineralizado al implante (BIC) en los lugares de implante en el hueso mandibular del conejo. Material y métodos: El experimento se realizó en el área edéntula del maxilar de 16 conejos adultos. Se expuso quirúrgicamente el hueso alveolar en el lado izquierdo (test) de 8 conejos y se preparó un hueco en la cresta ósea. Se retiró el hueso trabecular y el tejido de médula ósea, colocándose una membrana de barrera biorreabsorbible para cubrir el hueco. El lado derecho no sufrió ningún tratamiento y sirvió de control. Cuatro semanas mas tarde, se colocó un implante de forma roscada transversalmente a través del maxilar, penetrando las áreas de prueba y de control. Tras otras 4 semanas de cicatrización, los animales se sacrificaron para obtener cortes histológicos para histomorfometría. Las mandíbulas sin tratar de los 8 conejos sirvieron como especímenes de referencia. Resultados: En los conejos sometidos a cirugía las áreas (mm2) del hueso mineralizado y del tejido medular fueron similares para la prueba y el control (4.9 ± 1.7 vs. 5.1 ± 2.2 y 6.3 ± 5.7 vs. 6.8 ± 5.7, hueso y médula respectivamente). El BIC (%) para todas las roscas fue significativamente mas bajo en el lado de prueba que en el de control (32.1 ± 27.7 vs. 47.7 ± 20.3). La densidad de ósea (%) de toda el área experimental fue similar para la prueba y el control (48.5 ± 12.1 vs. 46.5 ± 9.3) así como la densidad ósea en el área en los valles entre las roscas y en su área espejo (43.0 ± 13.9 vs. 41.3 ± 13.5, y 40.2 ± 11.0 vs. 40.3 ± 7.2, área de roscas y área espejo respectivamente). La densidad ósea en el área total experimental en los conejos no tratados (vírgenes) fue del 35.9 ± 5.2%. Este valor fue significativamente mas bajo que los valores en el total de las áreas experimentales (test y control) de los conejos tratados quirúrgicamente. Del mismo modo, la densidad del área de referencia de los conejos no tratados fue de 25.4 ± 5.3%, que también fue significativamente mas baja que la densidad ósea del área periimplantaria de los conejos tratados quirúrgicamente. Conclusión: El trauma quirúrgico causado por la colocación de implantes en el maxilar de conejos estimuló significativamente la densidad ósea de los lugares de implantes. Sin embargo, la intervención quirúrgica de los lugares de implantes 4 semanas antes de la colocación de los implantes no estimuló mas la densidad ósea o el BIC. [source] Cutting Torque Measurements in Conjunction with Implant Placement in Grafted and Nongrafted Maxillas as an Objective Evaluation of Bone Density: A Possible Method for Identifying Early Implant Failures?CLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 1 2004Björn Johansson DDS ABSTRACT Background: Bone grafts are frequently used to enable the placement of dental implants in atrophied jaws. The biomechanical properties of bone grafts used in one- or two-stage implant procedures (in comparison with the use of nongrafted bone) are not well known. Purpose: The purpose of this study was (1) to measure cutting torques during the placement of self-tapping dental implants in nongrafted bone and in bone grafts, either as blocks or in a milled particulate form, in patients undergoing implant treatment in an edentulous maxilla and (2) to identify implants with reduced initial stability and to correlate these findings with a clinical classification of jawbone quality. Materials and Methods: The study included 40 consecutive patients with edentulous maxillas, 27 of whom were subjected to bone grafting prior to or in conjunction with implant placement (grafting group) and 13 of whom received implants without grafting (nongrafted group). Grafted bone from the iliac crest bone was used (1) as onlay blocks, (2) as maxillary sinus inlay blocks, or (3) in particulate form in the maxillary sinus. Implants were placed after 6 to 7 months of healing, except in the maxillary sinus inlay blocks, where implants were placed simultaneously. Cutting torque values were obtained from 113 grafted implant sites and from 109 nongrafted implant sites. Results: Significantly lower cutting torque values were assessed in grafted regions than in nongrafted regions, irrespective of grafting technique. Lower values were also seen for implants placed in block grafts after 6 months when compared to other grafting techniques used. The cutting torque values revealed an inverse linear relation to the Lekholm and Zarb bone quality index. Conclusion: The cutting torque values correlated well with the Lekholm and Zarb index of bone quality. Significantly lower cutting torque values were seen in grafted bone than in nongrafted bone. [source] Measurements of Buccal Tissue Volumes at Single-Implant Restorations after Local Bone Grafting in Maxillas: A 3-Year Clinical Prospective Study Case SeriesCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 2 2003Odont PhD, Torsten Jemt LDS ABSTRACT Purpose: The purpose of this study was to measure changes in buccal and proximal tissue volumes after local bone grafting and single-implant treatment. Materials and Methods: Ten patients were provided with buccal bone grafts 6 months prior to implant treatment in central upper incisor regions. Following a healing time of 6 months, abutments and single-implant crowns were installed and followed up for 2 years. Clinical photographs and impressions were taken prior to the surgical intervention as well as after crown placement and at first and second annual checkups. The photographs and study models were analyzed with regard to papilla regeneration and changes in buccal crest volume during the study period by means of a clinical papilla index and optical scanning of study models. Results: All bone grafts healed without problems. A significant reduction of the buccal crest volume (-50%, p <.01) was observed in the grafted area before abutment connection. However, a significant increase of tissue volume (+100%, p <.05) was noticed at the subsequent crown placement, followed by a second but slow reduction of the volume during the following 2 years of function. The interdental papillae increased significantly (p <.05) in volume during the first year, almost completely filling up the embrasure areas after 2 years. Conclusions: It may be concluded that local bone grafting seems to be a valuable protocol to create sufficient bone volume for implant placement. However, significant resorption of the graft may be present, which reduces the impact of grafting on the esthetic outcome. Instead, placement of the abutment cylinder and the crown seems to play a more important role for reestablishing the tissue volume at the implant-supported single crowns. [source] Dental injuries resulting from tracheal intubation , a retrospective studyDENTAL TRAUMATOLOGY, Issue 1 2009Jobst Vogel Thus, this retrospective study was conducted including the data of 115,151 patients. All patients involved had been exposed to general anesthesia between 1995 and 2005. The resulting tooth injuries were assessed according to the following parameters: age, kind of hospital conducting treatment, intubation difficulties, pre-existing tooth damage, type and localization of tooth, type of tooth damage, and the number of teeth injured. At least 170 teeth were injured in 130 patients, while patients 50 years of age and older were especially affected. In contrast to older patients where in the majority of cases the periodontium (lateral dislocation) was injured, in younger patients dental hard tissue (crown fracture) was more likely to be affected. It was calculated that patients from the cardiothoracic surgery clinic were showing the highest risk of tooth damage. In more than three-fourth of all cases the anterior teeth of the maxilla, especially the maxillary central incisors, were affected. Pre-existing dental pathology like caries, marginal periodontitis and tooth restorations were often distinguishable prior to operation. Mouthguards in connection with tracheal intubation are not generally recommended as preventive device, due to the already limited amount of space available. Instead, pre-existing risk factors should be thoroughly explored before the induction of intubation narcosis. [source] An experimentally calibrated finite element study of maxillary traumaDENTAL TRAUMATOLOGY, Issue 5 2007Michael J Casas Abstract,,, A baseball injury to an instrumented human cadaver maxillae was simulated with a regulation (142 g) baseball traveling at 14 m s,1. Measurements of strain were obtained with three-axis strain gauge rosettes located at the medial palate and both canine fossae. A three-dimensional finite element (FE) model of a dentate human maxilla was constructed from computed tomography scans of the skull of an adolescent. This three-dimensional mathematical model of the maxilla was deemed geometrically accurate by convergence testing when the model's degrees of freedom approximated 74 000. The simulated load case involved a transient dynamic impact to the medial maxilla with boundary conditions imposed at skeletal buttresses of the model. The model was calibrated through direct comparison with the displacements and principal strains gathered from experimental and epidemiological data. The comparison of experimental and calculated principal strains as a result of the simulated impacts revealed a 1.7,11.4% difference. [source] Segmental osteotomy to reposition multiple osseointegrated dental implants in the anterior maxilla in a trauma patientDENTAL TRAUMATOLOGY, Issue 1 2007Shou-Yen Kao Abstract,,, A 16-year-old young man had severe loss of alveolar bone and lost four teeth in the anterior maxilla because of traumatic injury in a traffic accident. To overcome the surgically compromised condition for implant rehabilitation, the deficient ridge was augmented by autogenous bone graft from the mandibular symphysis. The augmented ridge had much improvement in width but less in vertical height. Four implants were placed to gain initial osseointegration. Segmental osteotomy was performed to occlusally reposition the implants and bone for 5-mm in the anterior maxilla. After 2 years of clinical follow-up, the rehabilitation outcome is satisfactory and stable. [source] Single-tooth implant treatment in the anterior region of the maxilla for treatment of tooth loss after trauma: a retrospective clinical and interview studyDENTAL TRAUMATOLOGY, Issue 3 2003Lars Andersson Abstract,,, The aim of this study was to evaluate the results of single-tooth implant treatment in patients where teeth have been lost as a result of trauma. Also, the patients' and professionals' opinions regarding the final outcome of treatment were assessed. Thirty-four patients with 42 lost teeth were evaluated by clinical and radiographic examinations and interviews 2,5 years after treatment. A professional who had not taken part in the treatment evaluated the implant crowns. Central maxillary incisors were the most frequently lost and replaced teeth after trauma (75%) followed by lateral incisors (21%). In patients with incomplete growth, implant treatment was generally postponed until completion of growth. Lack of space was treated by presurgical orthodontics (7%) or by selecting an implant with a reduced diameter (5%). Deficiency of bone was seen in 17% and was treated by bone grafting or local augmentation prior to implant surgery. Patients who had lost two or more teeth after trauma were all subjected to bone grafting. Preservation of roots in the alveolar process seemed to maintain the bone volume enabling better conditions for later implant placement. Forty-one implants (97.6%) were integrated successfully. Complications were few and of minor importance (9.5% before and 12% after cementation of crowns) and could all be managed. No or minimal bone loss was seen. In general, the patients felt that they received good care and that they were well informed about their treatment. Some patients reported that the local anesthesia procedure was not pain-free, but 71% of the patients experienced the treatment as pain-free. For each of the variables (color, shape, height, and size of the crowns), the highest degree of satisfaction was noted in 93,98% of the patients and 91,95% of the single evaluating professional. Given that the patients have finished growth and a careful treatment planning and timing are performed, the functional and esthetical outcome of single-tooth implant treatment today is excellent and can be recommended for replacing tooth losses after trauma in the anterior region of the maxilla. [source] Identification of Tgf,1i4 as a downstream target of Foxc1DEVELOPMENT GROWTH & DIFFERENTIATION, Issue 5 2006Paula Sommer Craniofacial development is severely affected by null mutations in Foxc1, indicating a multifunctional role for Foxc1 in ocular, maxilla and mandible, skull and facial gland development. To delineate signaling pathways in which Foxc1 is involved we compared the transcriptomes of whole heads of Foxc1+/+ and Foxc1,/, embryos using a candidate cDNA array comprising genes expressed in the head mesenchyme and ocular region, and a 7K oligo array. Absence of Foxc1 led to downregulation of Stat1 and Galnt4, and upregulation of Tgf,1i4 at embryonic day 13.5 in the developing head mesenchyme. Comparative analyses revealed differences in the expression pattern of Tgf,1i4 in the head mesenchyme of Foxc1,/, and Foxc1+/+ embryos. In the ocular regions of Foxc1,/, embryos, Tgf,1i4 was expressed in higher levels in the conjunctival epithelium and in the condensing mesenchyme on the nasal aspect of the developing eye while in wild-type embryos more intense expression was seen in the mesenchyme on the temporal aspect of the eye. Such data indicate that Foxc1 regulation of Tgf,1i4 is complex and may be cell-type dependent. Analysis of the regulation of Tgf,1i4 by Foxc1 in a more homogenous cell population, mesenchymal cells isolated from the periocular region revealed that, in these cells, Foxc1 negatively regulated Tgf,1i4 expression, presumably via secreted factors such as TGF-,1. Since Foxc1 expression is essential for normal craniofacial development, it is possible that its downstream targets play a role in the development of the phenotypes associated with null mutations in Foxc1. [source] Embryogenesis and ossification of Emydura subglobosa (Testudines, Pleurodira, Chelidae) and patterns of turtle developmentDEVELOPMENTAL DYNAMICS, Issue 11 2009Ingmar Werneburg Abstract Using the Standard Event System (SES) to study patterns of vertebrate development, we describe a series of 17 embryos of the pleurodire turtle Emydura subglobosa. Based on a sequence heterochrony analysis including 23 tetrapod taxa, we identified autapomorphic developmental shifts that characterise Testudines, Cryptodira, and Pleurodira. The main results are that Testudines are characterised by an autapomorphic late neck development, whereas pleurodires and cryptodires show a different developmental timing of the mandibular process. Additionally, we described the ossification pattern of E. subglobosa and compared the data to those of five other turtles. Pleurodires show the epiplastron to ossify before or simultaneously with maxilla and dentary. In contrast, cryptodires show a later ossification of this bone. Because evolutionary developmental studies on turtles have previously focused only on "model organisms" that all belong to Cryptodira, we underline the necessity to include a pleurodire taxon for a more comprehensive, phylogenetically more informative approach. Developmental Dynamics 238:2770,2786, 2009. © 2009 Wiley-Liss, Inc. [source] Genetic disruption of CYP26B1 severely affects development of neural crest derived head structures, but does not compromise hindbrain patterningDEVELOPMENTAL DYNAMICS, Issue 3 2009Glenn Maclean Abstract Cyp26b1 encodes a cytochrome-P450 enzyme that catabolizes retinoic acid (RA), a vitamin A derived signaling molecule. We have examined Cyp26b1,/, mice and report that mutants exhibit numerous abnormalities in cranial neural crest cell derived tissues. At embryonic day (E) 18.5 Cyp26b1,/, animals exhibit a truncated mandible, abnormal tooth buds, reduced ossification of calvaria, and are missing structures of the maxilla and nasal process. Some of these abnormalities may be due to defects in formation of Meckel's cartilage, which is truncated with an unfused distal region at E14.5 in mutant animals. Despite the severe malformations, we did not detect any abnormalities in rhombomere segmentation, or in patterning and migration of anterior hindbrain derived neural crest cells. Abnormal migration of neural crest cells toward the posterior branchial arches was observed, which may underlie defects in larynx and hyoid development. These data suggest different periods of sensitivity of anterior and posterior hindbrain neural crest derivatives to elevated levels of RA in the absence of CYP26B1. Developmental Dynamics 238:732,745, 2009. © 2009 Wiley-Liss, Inc. [source] Heddleichthys, a new tristichopterid genus from the Dura Den Formation, Midland Valley, Scotland (Famennian, Late Devonian)ACTA ZOOLOGICA, Issue 2009Daniel Snitting Abstract A new tristichopterid genus, Heddleichthys, from the Famennian of Scotland is described based on material previously assigned to a number of different genera, including Glyptopomus, Gyroptychius and Eusthenopteron. The validity of the new genus is established by a discussion of the reasons for the invalidity of the previous assignments. Heddleichthys is characterized by a combination of derived and primitive tristichopterid features. Derived features include the presence of symphyseal dentary fangs and premaxillary pseudofangs, a diamond-shaped symmetric caudal fin, a low posterodorsal expansion of the maxilla, and a posteriorly positioned kite-shaped pineal series. Primitive features include a postorbital and jugal contribution to the orbital margin and a parasphenoid with a ventral keel. External dermal bones are rather poorly preserved in the referred material, with few easily discernible sutures. The holotype specimen, a three-dimensionally preserved skull, was scanned by computed tomography to reveal well-preserved internal dermal bones, including entopterygoids, vomers and parasphenoid. There is no preserved endoskeletal material. As the first representative of derived tristichopterids described from Britain, Heddleichthys lends support to the idea that faunal dispersion between Gondwana and Laurussia in the Late Devonian was widespread. Derived tristichopterids have been described from all continents except South America. In contrast, the basal tristichopterids Eusthenopteron and Tristichopterus are still only described from Laurussia. [source] Non-invasive longitudinal assessment of facial growth in children and adolescents with hypohidrotic ectodermal dysplasiaEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 4 2008Claudia Dellavia Facial growth patterns in 12 subjects (six boys and six girls) with hypohidrotic ectodermal dysplasia (HED) were analyzed and compared with facial growth patterns obtained in healthy reference peers. All subjects with HED were aged 7 yr (mean age ± standard deviation: 7.08 ± 0.41 yr) at the first examination and 14 yr (mean age ± standard deviation: 14.56 ± 0.34 yr) at the last examination. In each subject, the three-dimensional coordinates of facial landmarks were collected non-invasively at eight subsequent years. The volumes of forehead, nose, maxilla and mandible, upper lips, and lower lips were estimated. For each facial volume, differential values between different time points were calculated individually, separately for the ,childhood' (7,10 yr) and the ,adolescence' (11,14 yr) growth period in both HED and reference subjects. Children and adolescents with HED had a slightly reduced global facial growth in comparison with normal reference peers. The peak mandibular and maxillary development was delayed by approximately 2 yr towards later adolescence. The present non-invasive system seems to be useful for studying longitudinal changes of facial growth in healthy and syndromic subjects. [source] Variability in permanent tooth emergence sequences in Flemish childrenEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 1 2008Roos Leroy The aim of the present study was to investigate the variability in permanent tooth emergence sequences in Flemish children. Data were obtained in the Signal-Tandmobiel project, a 6-yr prospective longitudinal oral health screening survey in Belgium. Bayesian statistical analyses, taking into account the interval-censored character of the data, were performed. The analyses indicated that no sequence was common in a quadrant to more than 19% of the sample. When only those emergence sequences are considered with a prevalence of 1% or more, 21 variations can be expected in the maxilla and 15,22 variations in the mandible. These variations ,cover' 84,88% of all sequences. The presentation of emergence sequences solely based on means or medians should thus be regarded as misleading. [source] Factors influencing proximal dental contact strengthsEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 5 2000Christof E. Dörfer The aim of this study was to systematically measure proximal contact strength in complete natural dentitions of 30 adults (25.3±3.0 years of age), and to analyze its relationship to tooth type, tooth location, chewing effort and time of day variation. The contact strengths were measured dynamically during removal of a calibrated 0.05-mm-thick metal strip between the proximal contacts of adjacent teeth. Proximal contact strengths were lower in the maxilla (2.51±1.36 N) compared to the mandible (4.26±1.88 N). Within the jaws, the lowest proximal contact strength was measured between canine and first premolar (2.91±1.79 N) and the highest between second premolar and first molar (3.73±1.95 N). Chewing increased the proximal contact strength within the maxilla (before: 2.51±1.36 N, after: 3.02±1.45 N) but it remained unchanged in the mandible (before: 4.26±1.88 N, after: 4.22±1.85 N). The proximal contact strength increased significantly from morning (3.39±1.86 N) to noon (3.61±1.77 N), and then decreased in the afternoon (3.43±1.60 N). It was concluded that proximal contact strength can be significantly influenced by location, tooth type, chewing and time of day variation. Based on the differences in distribution due to the effect of chewing and time of day, it is speculated that proximal contact strength is a physiological entity of multifactorial origin. [source] Reverse facial artery,submental artery mandibular osteomuscular flap for the reconstruction of maxillary defects following the removal of benign tumorsHEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 6 2009Wei-Liang Chen DDS Abstract Background. Functional and aesthetic restoration in maxillary reconstruction remains a challenge. Although many free flap procedures have become popular in maxillary reconstruction, these microsurgical methods have certain limitations and risks. This study assessed the reliability of the reverse facial artery,submental artery mandibular osteomuscular flap for reconstructing maxillary defects. Methods. Eight maxillary defects following benign tumor ablation were repaired with reverse facial artery,submental artery mandibular osteomuscular flaps. The patients ranged in age from 16 to 33 years; 5 were male and 3 were female. Maxillary odontogenic myxoma was present in 3 cases, maxillary fibrous dysplasia and ameloblastoma in 2 cases each, and chondromyxoid fibroma in 1 case. The defects were classified as class 2a. Results. Primary reconstruction of the maxilla was carried out using a pedicled mandibular osteomuscular flap. No flap failures occurred. Dental reconstruction was successful in all patients. Proper aesthetics and complete functionality were obtained, and there were no donor-site problems. The patients were followed for 12 to 24 months, with an average of 18.6 months, and no recurrence was encountered. Conclusion. The reverse facial artery,submental artery mandibular osteomuscular flap is safe, quick, and simple to elevate. The flap can be used reliably for reconstructing maxillary defects. © 2009 Wiley Periodicals, Inc. Head Neck, 2009 [source] Evolution of maxillofacial brown tumors after parathyroidectomy in primary hyperparathyroidismHEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 11 2008Jaime Alonso Reséndiz-Colosia MD Abstract Background. Brown tumor occasionally affects the facial bones. Clinically, these lesions can be mistaken for a neoplasm. Opinions are divided on the course of management of the bony lesions once parathyroidectomy has been carried out. Methods. We treated 22 patients with primary hyperparathyroidism and osteitis fibrosa cystica and observed their clinical and biochemical recovery. Results. Fifteen patients (68.2%) had brown tumors in mandible, and 7 (31.8%) in maxilla. After parathyroidectomy, 21 patients had normal total serum calcium values. All brown tumors presented a spontaneous progressive regression; in 18cases, regression was total, with a mean time period of 10months. Two patients had partial regression after nearly 2years. Another 2 patients were lost to follow-up. Conclusions. After successful parathyroid surgery, the bony lesions tended to regress spontaneously, either partially or completely. However, if the lesion is disfiguring or symptomatic, surgical excision may be indicated. © 2008 Wiley Periodicals, Inc. Head Neck, 2008 [source] Zygomaticomaxillary buttress reconstruction of midface defects with the osteocutaneous radial forearm free flapHEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 10 2008Patricio Andrades MD Abstract Background. The purpose of this study was to evaluate morbidity, functional, and aesthetic outcomes in midface zygomaticomaxillary buttress reconstruction using the osteocutaneous radial forearm free flap (OCRFFF). Methods. A retrospective review of 24 consecutive patients that underwent midface reconstruction using the OCRFFF was performed. All patients had variable extension of maxillectomy defects that requires restoration of the zygmatico-maxillary buttress. After harvest, the OCRFFF was fixed transversely with miniplates connecting the remaining zygoma to the anterior maxilla. The orbital support was given by titanium mesh when needed that was fixed to the radial forearm bone anteriorly and placed on the remaining orbital floor posteriorly. The skin paddle was used for intraoral lining, external skin coverage, or both. The main outcome measures were flap success, donor-site morbidity, orbital, and oral complications. Facial contour, speech understandability, swallowing, oronasal separation, and socialization were also analyzed. Results. There were 6 women and 18 men, with an average age of 66 years old (range, 34,87). The resulting defects after maxillectomy were (according to the Cordeiro classification; Disa et al, Ann Plast Surg 2001;47:612,619; Santamaria and Cordeiro, J Surg Oncol 2006;94:522,531): type I (8.3%), type II (33.3%), type III (45.8%), and type IV (12.5%). There were no flap losses. Donor-site complications included partial loss of the split thickness skin graft (25%) and 1 radial bone fracture. The most significant recipient-site complications were severe ectropion (24%), dystopia (8%), and oronasal fistula (12%). All the complications occurred in patients with defects that required orbital floor reconstruction and/or cheek skin coverage. The average follow-up was 11.5 months, and over 80% of the patients had adequate swallowing, speech, and reincorporation to normal daily activities. Conclusions. The OCRFFF is an excellent alternative for midface reconstruction of the zygomaticomaxillary buttress. Complications were more common in patients who underwent resection of the orbital rim and floor (type III and IV defects) or external cheek skin. © 2008 Wiley Periodicals, Inc. Head Neck, 2008 [source] Epithelioid osteosarcoma presenting as a rapidly expanding maxillary mass,HEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 7 2007Joseph Rinaggio DDS Abstract Background. Osteosarcomas of the jaws account for less than 10% of reported neoplasms of this type. Patients with osteosarcoma in this region tend to be in the late-third to mid-fourth decades of life. The osteoblastic, chondroblastic, and fibroblastic variants constitute the majority of lesions. Methods. A mass was observed in the maxilla of a 50-year-old male who presented for a complete odontectomy. Over the ensuing weeks, the mass substantially increased in size, despite multimodality treatment efforts. Results. Radiographic findings revealed a mixed density mass of the left maxilla. Histologic, immunohistochemical, and electron microscopy examination of the tumor showed a malignant mesenchymal neoplasm consisting of sheets of epithelioid and spindle cells exhibiting focal osteoid formation. Conclusions. We report a rare and aggressive case of epithelioid osteosarcoma arising in the maxillofacial complex. © 2007 Wiley Periodicals, Inc. Head Neck, 2007 [source] | ||||||||||||||||||||||||||||||||||