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Mandible
Kinds of Mandible Terms modified by Mandible Selected AbstractsHN09P ASSESSMENT OF FREE FIBULAR BONE IN THE RECONSTRUCTED MANDIBLE USING THREE-DIMENSIONAL COMPUTER GENERATED IMAGESANZ JOURNAL OF SURGERY, Issue 2007H. Nabi We report the preliminary results of the Royal Adelaide Hospital experience with multidimensional simulated views of the fibula-flap reconstructed mandible. The free fibular flap is a well recognised option for mandibular reconstruction. What is not well understood however is how the fibula behaves in comparison to the dentate mandible. To date, skeletal remodelling and bone atrophy has only been assessed using standard orthopantogram films. For many years three-dimensional (3D) computer generated models using data from CT scans have been utilised for craniofacial reconstruction. We proposed that these images will enable us to more accurately visualise the integration of the transplanted graft within the mandible. We recalled and CT scanned patients from 2004 to 2006 that underwent free fibular flaps for reconstruction of mandibular malignancy and performed 3D reconstruction of these images. This is the first reported series of multidimensional computer generated images to assess bone in the reconstructed mandible. [source] Disparate osteogenic response of mandible and iliac crest bone marrow stromal cells to pamidronateORAL DISEASES, Issue 5 2008D Stefanik Objective:, Long-term administration of intravenous bisphosphonates like pamidronate is associated with jaw osteonecrosis but axial and appendicular bones remain unaffected. Pathogenesis of bisphosphonate-associated jaw osteonecrosis may relate to skeletal site-specific effects of bisphosphonates on osteogenic differentiation of bone marrow stromal cells (BMSCs) of orofacial and axial,/,appendicular bones. This study evaluated and compared skeletal site-specific osteogenic response of mandible (orofacial bone) and iliac crest (axial bone) human BMSCs to pamidronate. Materials and methods:, Mandible and iliac crest BMSCs from six normal healthy volunteers were established in culture and tested with pamidronate to evaluate and compare cell survival, osteogenic marker alkaline phosphatase, osteoclast differentiation in co-cultures with CD34+ hematopoietic stem cells, gene expression of receptor activator of NF,B ligand (RANKL) and osteoprotegerin, and in vivo bone regeneration. Results:, Mandible BMSCs were more susceptible to pamidronate than iliac crest BMSCs based on decreased cell survival, lower alkaline phosphatase production, and structurally less organized in vivo bone regeneration. Pamidronate promoted higher RANKL gene expression and osteoclast recruitment by mandible BMSCs. Conclusion:, Mandible and iliac crest BMSC survival and osteogenic differentiation are disparately affected by pamidronate to favor dysregulated mandible bone homeostasis. [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] Osteonecrosis of the Mandible or Maxilla Associated with the use of New Generation BisphosphonatesTHE LARYNGOSCOPE, Issue 1 2006Matthew C. Farrugia DO Objective: The use of bisphosphonates is well established for the treatment of patients with metastatic bone disease, osteoporosis, and Paget's disease. Osteonecrosis of the mandible or maxilla associated with the use of bisphosphonates is a newly described entity never before discussed in the otolaryngology literature. In this paper, we review a series of patients diagnosed with osteonecrosis, all treated with new generation bisphosphonates. Our objective is to inform and educate others, particularly otolaryngologists/head and neck surgeons, about this drug induced entity, a condition that should be recognized early to avoid potential devastating consequences. Study Design: Retrospective chart review of a series of patients from a tertiary referral center. Methods: Pathology reports of specimens submitted from either the mandible or maxilla were reviewed from the previous 12 months. Any patient diagnosed with osteonecrosis without evidence of metastatic disease at that site was included; those with a previous history of radiation therapy were excluded. Each patient's medical history and profile were reviewed. Results: Twenty-three patients were identified with osteonecrosis of the mandible or maxilla. All of these were associated with the use of new generation bisphosphonates: zolendronate (Zometa, Novartis), pamidronate (Aredia, Novartis), and alendronate (Fosamax, Merck). Eighteen patients with known bone metastases had been treated with the intravenous form, whereas five patients with either osteoporosis or Paget's disease were using oral therapy. Patients typically presented with a nonhealing lesion, often times the result of previous dental intervention. Although the majority of these patients were treated with conservative surgical debridement, we present a case requiring a near total maxillectomy. Conclusions: Drug induced osteonecrosis of the mandible or maxilla has been recently recognized as a sequelae of treatment with the new generation of bisphosphonates. Most patients can be treated with conservative surgical debridement and cessation of bisphosphonate therapy, whereas a few may require radical surgical intervention. Other recommendations include regimented prophylactic care with an assessment of dental status before the administration of bisphosphonates, avoidance of dental procedures, and close monitoring of oral hygiene. [source] Laser-Welded Titanium Frameworks Supported by Implants in the Partially Edentulous Mandible: A 10-Year Comparative Follow-Up StudyCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 3 2008Anders Örtorp DDS, PhD/Odont Dr ABSTRACT Background: Comparative long-term knowledge of different framework materials in the partially edentulous implant patient is not available. Purpose: To report and compare 10-year data on free-standing implant-supported partial prostheses with laser-welded titanium (test) and conventional gold alloy (control) frameworks. Materials and Methods: Altogether, 52 partially edentulous patients were consecutively provided with laser-welded prostheses (n = 60) in the partially edentulous lower jaw (test group). A control group of 52 randomly selected patients with gold alloy castings (n = 60) was used for comparison. Clinical and radiographic 10-year data were retrospectively collected and evaluated for both groups. Results: The overall 10-year implant cumulative survival rate (CSR) was 93.0% (loaded implants, 96.4%), with a 10-year implant CSR of 91.5 and 94.7% for test and control implants, respectively (p > .05). Out of a total of 22 lost implants, 17 implants (77.3%) were shorter than 10 mm. The overall 10-year prosthesis CSR was 93.7%, with a corresponding 10-year CSR of 88.4 and 100% for test and control groups, respectively (p < .05). Average 10-year bone loss was 0.46 mm (SD 0.47) and 0.69 mm (SD 0.53) for the test and control groups (p < .001), respectively. Only 1% of the implants had >3 mm accumulated bone loss after 10 years. Altogether, 10 of the prostheses in both groups had implant component mechanical problems (8.3%). None of the frameworks or implants fractured, but more fractures of porcelain veneers were observed in the test group (p < .05). Conclusion: The protocol of implant treatment in the partially edentulous jaw functioned well during 10 years, although prosthodontic maintenance was required. However, laser-welded titanium frameworks presented more problems as compared with gold alloy frameworks. More loaded implants were lost (p < .05), and higher incidence of porcelain chipping was noted in the test group (p < .05). However, bone loss was on an average lower for the test group during the 10 years of follow-up (p < .001). [source] Immediate Loading of Brånemark System Implants®: A Comparison Between TiUniteTM and Turned Implants Placed in the Anterior MandibleCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 4 2006Kjell-Krister Fröberg DDS ABSTRACT Purpose:, The aim of the present study was to compare the treatment outcome of TiUniteTM - and turned-surfaced Brånemark System® (Nobel Biocare AB, Göteborg, Sweden) implants when applying immediate loading of cross-arch designed fixed partial dentures in the anterior mandible. Materials and Methods:, Fifteen patients with edentulous mandibles participated in the study. In one half of the jaw, between the exit of the nerve-vessel bundle and the midline, one type of implant was placed and in the remaining half the other type. The implants were loaded the day of surgery via a fixed, temporary supra-construction. Ten days later, the permanent one was screw retained to the implant pillars. Results:, The present 18-month clinical trial failed to demonstrate any differences regarding healing and cumulative success rate of an an-oxidized implant surface (TiUnite) and a turned (turned) one when implants in the anterior mandible were exposed to functional load within 24 hours after installation. Conclusion:, A high predictability regarding the treatment outcome for immediately loaded Brånemark implants in the anterior mandible was observed. Furthermore, no difference between the traditional turned and the an-oxidized implant surface (TiUnite) could be observed. However, it has to be stressed that all implants (irrespective of surface) were placed in the anterior mandible and also that all the patients demonstrated a high level of oral hygiene. [source] Functional Restoration of Implants on the Day of Surgical Placement in the Fully Edentulous Mandible: A Case SeriesCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 1 2005Alexandre-Amir Aalam DDS ABSTRACT Purpose: The purpose of this article is to report the clinical experience and outcome of a study of the functional rehabilitation of 16 completely edentulous mandibles with immediately loaded cross-arch screw-retained hybrid prostheses at the University of Southern California. Materials and Methods: After signing informed consent forms 16 patients (9 male, 7 female) aged 47 to 84 years (mean age, 62.6 ± 11.6 years) received 90 Brånemark System® Mk III dental implants (Nobel Biocare USA, Yorba Linda, CA, USA). Stability and radiographs of the dental implants were evaluated at the time of surgery, at 3 months, at 1 year, and at 3 years post loading. Results: Three implants failed to meet the criteria of success, bringing the cumulative success rate to 96.6%, with a 100% prosthetic success rate at 3 years. Thirty-nine (43.3%) of the dental implants placed were 15 mm in length. Seventy-seven (85.5%) of the dental implants were placed in high-density bone. At 3 years post loading, the average bone loss was ,1.2 ± 0.1 mm. Conclusion: Within the limitations of this study, restoration of implants by unreinforced hybrid prostheses at the time of placement provided satisfactory results. The outcome was stable at 3 years post restoration. Mandibular rehabilitation by functional loading of the implants on the day of the insertion requires the comprehension and proper application of surgical and restorative principles. [source] Clinical Assessment and Surgical Implications of Anatomic Challenges in the Anterior MandibleCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 4 2003Nuri Mraiwa BDS ABSTRACT Background: The anterior mandible is generally considered a rather safe surgical area, involving few risks of damage to vital anatomic structures. Nevertheless, both neurosensory disturbances and hemorrhages have been reported after implant surgery in that particular area. Purpose: With the increasing demand for oral implant placement, the anatomy of the anterior mandible should receive more attention. This review will focus on the anatomic peculiarities of the anterior mandible and the related clinical implications. Methods: The scientific evidence on the anatomic, histologic, physiologic, and clinical aspects of the neurovascularization of the anterior mandible will be reviewed. Results: Surgical complications may be attributed to the existence of a mandibular incisive canal with a true neurovascular supply. Potential risks may also be related to the presence of the lingual foramen and anatomic variations, such as an anterior looping of the mental nerve. Conclusions: Preoperative radiographic planning for oral implant placement in the anterior mandible should therefore not only consider all esthetic and functional demands but should also pay particular attention to the anatomic peculiarities of this region to avoid any neurovascular complications. [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] Early Loading of Four or Five Astra Tech Fixtures with a Fixed Cross-Arch Restoration in the MandibleCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 3 2002Bruno Collaert DDS ABSTRACT Background: A change in implant placement has emerged recently from two-stage to one-stage surgery and to earlier and even immediate loading of the fixtures. Purpose: The aim of this study was to verify whether four or five fixtures installed in the edentulous mandible were suitable for early loading with a cross-arch fixed restoration. Materials and Methods: In 25 consecutively treated patients (28,88 yr), four or five Astra Tech fixtures (Mölndal, Sweden) were installed in edentulous mandibles. During the same surgical procedure, the abutments were connected. An impression was taken immediately after surgery. All patients received a fixed prosthetic rehabilitation of 10 to 12 teeth made of a cast metal framework and acrylic teeth/gingiva within a month. The fixtures were followed up clinically and radiographically for 7 to 24 months. Bone level was measured from the most coronal point of the vertical part of the fixture to the most apical bone level mesially or distally. Results: No fixtures were lost during follow-up. No postoperative complications occurred. Radiographic analysis showed a mean bone level of 0.6 mm after 7 to 12 months. Fixtures followed up from 13 to 18 and 19 to 24 months showed a mean bone level of 0.7 mm. Around two fixtures, the bone level was found at the first implant thread. All other fixtures showed the bone level somewhere along the vertical unthreaded part of the fixture. Conclusions: Early loading within 1 month of four or five Astra Tech fixtures in the edentulous mandible is a predictable procedure for a follow-up period of 6 to 24 months. [source] One-Stage Operative Procedure Using Two Different Implant Systems: A Prospective Study on Implant Overdentures in the Edentulous MandibleCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 4 2001Andrew Tawse-Smith DDS, Cert Perio (Göteborg) ABSTRACT Background: Evidence-based reports are needed to support the application of a one-stage surgical protocol for unsplinted implants supporting mandibular overdentures. Purpose: To examine the feasibility and success of using two different dental implant systems (originally designed for two-stage operative technique) using a one-stage operative procedure in patients being rehabilitated with implant mandibular overdentures. Materials and Methods: The study sample involved 24 edentulous subjects (aged 55,80 yr) randomly allocated to two different implant systems, one with a machined titanium implant surface (Steri-Oss, Nobel Biocare, Göteborg, Sweden) and the other with a roughened titanium surface (Southern Implants, Ltd., Irene, South Africa). Two unsplinted implants to support implant overdentures were placed in the anterior mandible of all patients, using a standardized one-stage surgical and prosthodontic procedure. Primary stability and bicortical anchorage of the implants was mandatory before healing abutments were connected at the time of implant placement. Implant overdentures and their respective matrices were inserted following a standard 12-week healing period. Data relating to mobility tests, radiographs, and peri-implant parameters were documented at 12, 16, and 52 weeks after surgery. Results: A success rate of 95.8% for the Steri-Oss and 100% for the Southern Implants was found, without any statistically significant differences in the marginal bone loss. Significant changes in Periotest values were observed for both types between 12 and 52 weeks (p <.001). Minor changes were observed in the peri-implant parameters evaluated. Conclusions: These preliminary findings show a successful application of this one-stage approach for unsplinted implants supporting mandibular overdentures with Steri-Oss and Southern Implant Systems. [source] Effects of Implant Design and Surface on Bone Regeneration and Implant Stability: An Experimental Study in the Dog MandibleCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 1 2001Lars Rasmusson DMD ABSTRACT Background: Previous experimental studies have shown a higher degree of bone-implant contact for surface-enlarged implants compared with machined implants. Yet, there is insufficient evidence that such implants show higher stability and an increased survival rate. Purpose: The purpose of this investigation was to study the integration and stability of grit-blasted implants with retention elements on the implant neck, with and without marginal bone defects, compared with machined implants without retention elements. Materials and Methods: After tooth extraction of the mandibular premolars in six dogs, two grit-blasted, partly microthreaded Astra Tech implants and one standard Branemark implant were bilaterally placed in each dog. On one side, 3 ± 3 mm large buccal defects were created, to expose three to four implant threads. The contralateral side served as control, and no defects were made. The animals were sacrificed after 4 months of healing. Implant stability was measured using resonance frequency analysis at implant installation and after 4 months of healing. Histologic and histomorpho-metric evaluation was made after 4 months of healing. Results: Resonance frequency analysis indicated that all implants in the test and control groups were osseointegrated after 4 months, with a tendency toward higher implant stability for the Astra Tech implants. There was a statistically significant higher increase in resonance frequency for the Astra test implants compared with their corresponding controls. Histology and histomorphometry showed well-integrated implants with varying degrees of bone repair at the defect sites. The greater bone-implant contact for the Astra implants was statistically significant. No significant difference between the implants in amount of bone filling the threads was recorded. Conclusions: The Astra Tech implants tested showed a higher degree of bone,implant contact and higher level of bone regenerated at defect sites compared with the Brånemark implants. Resonance frequency analysis demonstrated a significantly higher increase in the Astra test implants compared with their control groups than did the Brånemark test implants versus their controls. [source] Mandibles and molars of the wood mouse, Apodemus sylvaticus (L.): integrated latitudinal pattern and mosaic insular evolutionJOURNAL OF BIOGEOGRAPHY, Issue 2 2007Sabrina Renaud Abstract Aim, The distinct nature of island populations has traditionally been attributed either to adaptation to particular insular conditions or to random genetic effects. In order to assess the relative importance of these two disparate processes, insular effects were addressed in the European wood mouse, Apodemus sylvaticus (Linnaeus, 1758). Location, Wood mice from 33 localities on both mainland and various Atlantic and western Mediterranean islands were considered. This sampling covers only part of the latitudinal range of A. sylvaticus but included the two main genetic clades identified by previous studies. Islands encompass a range of geographical conditions (e.g. small islands fringing the continent through large and isolated ones). Methods, The insular syndrome primarily invokes variations in body size, but ecological factors such as release from competition, niche widening and food availability should also influence other characters related to diet. In the present study, the morphology of the wood mice was quantified based on two characters involved in feeding: the size and shape of the mandibles and first upper molars. The size of the mandible is also a proxy for the body size of the animal. Patterns of morphological differentiation of both features were estimated using two-dimensional outline analysis based on Fourier methods. Results, Significant differences between mainland and island populations were observed in most cases for both the mandibles and molars. However, molars and mandibles displayed divergent patterns. Mandible shape diverged mostly on islands of intermediate remoteness and competition levels, whereas molars exhibited the greatest shape differentiation on small islands, such as Port-Cros and Porquerolles. A mosaic pattern was also displayed for size. Body and mandible size increased on Ibiza, but molar size remained similar to mainland populations. Mosaic patterns were, however, not apparent in the mainland populations. Congruent latitudinal variations were evident for the size and shape of both mandibles and molars. Main conclusions, Mosaic evolution appears to characterize insular divergence. The molar seems to be more prone to change with reduced population size on small islands, whereas the mandible could be more sensitive to peculiar environmental conditions on large and remote islands. [source] The temporal expression and localization of extracellular matrix metalloproteinase inducer (EMMPRIN) during the development of perio-dontitis in an animal modelJOURNAL OF PERIODONTAL RESEARCH, Issue 4 2010L. Liu Liu L, Li C, Cai X, Xiang J, Cao Z, Dong W. The temporal expression and localization of extracellular matrix metalloproteinase inducer (EMMPRIN) during the development of periodontitis in an animal model. J Periodont Res 2010; 45: 541,549. © 2010 John Wiley & Sons A/S Background and Objective:, We previously demonstrated extracellular matrix metalloproteinase inducer (EMMPRIN) was associated with the matrix metalloproteinases production of human periodontitis. The aim of this study was to investigate the temporal expression and localization of EMMPRIN during ligature-induced periodontitis in rats. Material and Methods:, Periodontitis was inducd in rats by placing a thread around the cervix of the first mandibular molar. Animals were killed 3, 7, 11, 15 or 21 d after ligation. Mandibles were processed for paraffin sections and stained with hematoxylin and eosin or picrosirius red. The distance from the amelocemental junction to the alveolar crest (ACJ,AC) and the area fraction (Area%) of collagen fibers were measured. EMMPRIN was examined by immunohistochemistry and quantified by positive cell counting. Correlation analyses were then performed. Results:, Histologically, alveolar bone was gradually destroyed from day 3 to 11 and then stabilized. Collagen fibers were slightly dissociated on day 3 and extensively broken on day 7. They were reconstructed from day 11 to 21. EMMPRIN was localized predominantly in infiltrating cells and adjacent fibroblasts in interdental gingiva. The number of EMMPRIN-positive cells increased on day 3, peaked on day 7 and then gradually subsided from day 11 to 21. Statistically, there was a moderate positive correlation regarding the ACJ,AC distance (r = 0.552, p < 0.01) and a strong negative correlation with the Area% of collagen fibers (r = ,0.808, p < 0.01). In gingival epithelium, the immunoreactivity was extremely strong in basal layer cells and sulcular epithelial cells in health. It was greatly enhanced in the inflamed conditions on days 3 and 7. In the interradicular bone, EMMPRIN was localized in the osteoclasts on days 3 and 7, as well as in the osteoblasts from day 11 onwards. Conclusion:, The expression and localization of EMMPRIN are temporally varied during the development of periodontitis. In addition, the inflammation-dependent expression of EMMPRIN might be involved in alveolar bone resorption and collagen breakdown. [source] The Effect of a Constant Electrical Field on Osseointegration after Immediate Implantation in Dog Mandibles: A Preliminary StudyJOURNAL OF PROSTHODONTICS, Issue 5 2007Yadollah Soleymani Shayesteh DDS Purpose: The long time span between insertion of implants and functional rehabilitation often inconveniences patients. Accelerating bone growth around dental implants can shorten this time span. This in vivo study evaluated the effect of a constant electrical field on bone growth around dental implants. Materials and Methods: Four mongrel dogs were used in this study. Sixteen dental implants were placed immediately after extraction of the first premolar and molar teeth. A constant electrical field (CEF) generator was placed in the mucoperiostal pouch created from the subperiostral dissection under the inferior border of the dog's mandible and connected to the experiment side fixtures. CEF provided 3 V of electrical potential during osseointegration. Histologic sections were stained with hematoxylin,eosin and observed under light microscopy. The sections were analyzed histomorphometrically to calculate the amount of newly formed bone. Statistical analysis was performed with SPSS 11.0 computer software (,= 0.05). Results: At the end of the first stage of the osseointegration (90 days) CEF group sections showed enhanced growth of the trabeculae compared with the control group. Statistical analysis revealed significant differences between experimental and control groups. Bone contact ratio was statistically significant in the experimental group (p= 0.001). An increase in the local bone formation and bone contact ratio was observed with direct electrical stimulation of the implant and the bone area around the implant. Conclusion: Minimal direct electrical current, which can produce an electrical field around the implant, can increase the amount of bone formation and decrease the time of osseointegration. [source] Short Implants Placed One-Stage in Maxillae and Mandibles: A Retrospective Clinical Study with 1 to 9 Years of Follow-UpCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 1 2007Paulo Maló DDS ABSTRACT Background:, The use of short implants (7,8.5 mm) has historically been associated with lower survival rates than for longer implants. However, recent clinical studies indicate that short implants may support most prosthetic restorations quite adequately, but still clinical documentation is sparse. Purpose:, The purpose of this study was to report on the placement of short Brånemark implants, testing the hypothesis that short implants in atrophied jaws might give similar long-term implant survival rates as longer implants used in larger bone volumes. Materials and Methods:, This retrospective clinical study included 237 consecutively treated patients with 408 short Brånemark implants supporting 151 fixed prostheses. One hundred thirty-one of the implants were 7-mm long, and 277 were 8.5-mm long. Final abutments were delivered at the time of surgery, and final prostheses were delivered 4 to 6 months later. Results:, One hundred and twenty six of the 7-mm implants (96%) have passed the 1-year follow-up; 110 (84%), the 2-year follow-up; and 88 (67%), the 5-year follow-up. Five implants failed in four patients before the 6-month follow-up, giving a cumulative survival rate of 96.2% at 5 years. The average bone resorption was 1 mm (SD=0.6 mm) after the first year and 1.8 mm (SD=0.8 mm) after the fifth year of function. Two hundred sixty nine of the 8.5-mm implants (97%) have passed the 1-year follow-up; 220 (79%), the 2-year follow-up; and 142 (51%), the 5-year follow-up. Eight implants failed in seven patients before the 6-month follow-up, giving a cumulative survival rate of 97.1% at 5 years. The average bone resorption was 1.3 mm (SD=0.8 mm) after the first year and 2.2 mm (SD=0.9 mm) after the fifth year of function. Conclusions:, The cumulative survival rates of 96.2 and 97.1% at 5 years for implants of 7.0- and 8.5-mm length, respectively, indicate that one-stage short Brånemark implants used in both jaws is a viable concept. [source] Prospective Follow-Up Study of 95 Patients with Edentulous Mandibles Treated According to the Branemark Novum ConceptCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 1 2003Per Engstrand DDS ABSTRACT Background: The long-term predictability reported with the traditional two-staged Brånemark method has led to developments aimed at simplifying the technique and reducing healing time. Results from a pilot study using the Brånemark Novum concept are promising, and it has been shown possible to fabricate and deliver an implant-supported fixed prosthesis to the patient on the day of surgery. Purpose: The objective of this study is to report clinical and radiographic outcomes in a group of patients treated according to the Brånemark Novum concept. Materials and Methods: Ninety-five patients with edentulous mandibles were consecutively included in the study. Three specially designed fixtures were placed in each patient (285 fixtures in total) using drilling templates. The fixtures were immediately splinted with a prefabricated substructure, and fixed prostheses were delivered the same day in 67% of the patients. For the rest, prosthesis delivery ranged from 1 to 40 days (mean 5.6 d). Clinical and radiographic examinations were performed after 3 months, 6 months, 1 year, and then annually. The follow-up time was 1 to 5 years (mean 2.5 yr). Results: The cumulative prosthesis survival rate was 99%. Eighteen fixtures (6.3%) failed in 13 patients. Kaplan-Meier survival estimates demonstrated a probability implant survival at 1 year of 95.0% (94 patients), at 3 years of 93.3% (47 patients), and at 5 years of 93.3% (9 patients). The mean bone loss was 0.73 mm between the examinations at 3 months and 1 year, 0.16 mm during the second year, and 0.13 mm annually during years 3 to 5. Conclusions: Comparable results, related to continuous prosthesis stability, were shown for the Novum approach compared with the traditional two-staged procedure. Survival of individual fixtures is lower when immediate loading is applied. [source] Long-term Follow-up of Severely Atrophic Edentulous Mandibles Reconstructed with Short Branemark ImplantsCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 4 2000Bertil Friberg DDS ABSTRACT Background: Oral implant treatment (Brånemark System) of edentulous mandibles has been presented in numerous studies. However, with regard to the severely atrophic lower jaw, no long-term follow-up studies with solely short implants are available. Purpose: The purpose of the present investigation was to retrospectively follow the long-term treatment outcome of patients with severely resorbed edentulous mandibles being subjected to oral implant placement with short (6,7 mm) Brånemark implants. Materials and Methods: A total of 247 standard (7 mm long, 3.75 mm) and 13 wide (6 mm long, 5 mm) implants were inserted in 49 patients, all of whom exhibited severe resorption of edentate mandibles. Fixed implant-supported prostheses were manufactured for 45 patients, whereas 4 patients received overdentures. The patients were followed for a mean period of 8 years (range, 1,14 yr). Results: Seventeen implants failed during the study period (cumulative implant survival rate 95.5% at 5-yr and 92.3% at 10-yr follow-up). Implant-supported constructions were worn continuously throughout the investigation by all study subjects. Marginal bone loss, measured after 1, 5, and 10 years of function, concurred with studies of Brånemark implants placed in more voluminous mandibles. No major clinical or construction complications occurred in the followed patients. Conclusions: The outcome of the present study showed that placement of short Brånemark implants without the use of bone grafting procedures for reconstruction of severely atrophic edentulous mandibles is a highly predictable treatment procedure. [source] Applications of cone-beam computed tomography in fractures of the maxillofacial complexDENTAL TRAUMATOLOGY, Issue 4 2009Werner H. Shintaku Several studies support the use of conventional two-dimensional imaging for traumas involving mainly the mandible, but for more complex situations advanced imaging modalities such as computed tomography (CT) and magnetic resonance imaging have higher indication. Nowadays, besides CT, cone-beam computed tomography (CBCT) has appeared as a reasonable and reliable alternative considering radiation dosage, image quality and comfort for the patient. The purpose of this study was to review the fracture patterns involving the maxillofacial complex, provide a technical and practical comparison between CT and CBCT, and finally present the potential applications of CBCT illustrated with clinical examples. [source] Studies on dentin grafts to bone defects in rabbit tibia and mandible; development of an experimental modelDENTAL TRAUMATOLOGY, Issue 1 2009Lars Andersson This property may possibly be used as an alternative or supplement to bone grafting to defective areas after trauma prior to treatment with osseointegrated implants. Hence, the objective of this study was to investigate if dentin can be used as a graft in bone defects in an experimental rabbit model. Materials and Methods:, Eight New Zealand White Rabbits were used to prepare bone cavities either in the angle of the mandible or tibia. Six of the eight tibial and six of the eight mandibular bone defects were filled with dentin blocks from human premolars which were extracted for orthodontic treatment. Two mandibular and two tibial bone cavities were used as controls and all the rabbits were sacrificed after 3 months. Radiographic and histological examinations were performed. Results:, There was a difference in healing pattern between the mandibular and tibial defects. In the mandible, the dentin blocks were resorbed to a larger extent and more often surrounded by fibrous tissue, probably due to the fact that the dentin blocks were mobile because of the thin mandibles and muscular activity in that area. Only some dentin blocks were ankylosed with the mandibular bone. In the tibia however, all dentin blocks were fused to bone over a large area. Osseous replacement resorption was seen. In control cavities, bone formation was seen but was never complete. No signs of inflammatory changes were seen in any fused grafts. Conclusions:, Dentin grafts have a potential to be incorporated in bone without inflammation and can be used as bone inducer and later replaced by bone. Thus, rabbit tibia served as a better model for further studies of this phenomenon when compared to the mandible. [source] The conservative treatment of pediatric mandibular fracture with prefabricated surgical splint: a case reportDENTAL TRAUMATOLOGY, Issue 4 2007Ceyda Kocabay Abstract,,, The use of rigid fixation in children is controversial and may cause growth retardation along cranial suture lines. Intermaxillary fixation for mandibular fractures should be used cautiously as bony ankylosis in the temporomandibular joint (TMJ) and trismus may develop. The high osteogenic potential of the pediatric mandible allows non-surgical management to be successful in younger patients with conservative approaches. In this case, successful conservative treatment of mandibular fracture of a 3-year-old patient is presented. [source] Conservative treatment of paediatric mandibular fracture by the use of orthodontic appliance and rubber elastics: report of a caseDENTAL TRAUMATOLOGY, Issue 1 2005Petter J. E. Gawelin Abstract,,, Treatment principles of paediatric mandibular fractures may differ from the treatment of the adult population in that a conservative approach is in most cases advocated before the use of internal rigid fixation with plates and screws. This is because of a relative high risk of disturbed facial skeletal growth and risk of damaging unerupted teeth. Knowledge of conservative treatment options is essential in order to minimize these risks and one option is presented in this paper. This case report describes a 5-year-old girl that sustained an open fracture of the mandible and who was successfully treated by the means of applying orthodontic brackets and an arch bar combined with ligatures and rubber elastics. [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] Insulin-like growth factors, hepatocyte growth factor and transforming growth factor-, in mouse tongue myogenesisDEVELOPMENT GROWTH & DIFFERENTIATION, Issue 1 2003Akira Yamane Many reports have shown that tongue striated muscles have several unique characteristics not found in other skeletal muscles such as limb and trunk. Several peptide growth factors are reported to play important roles in skeletal myogenesis. In this article, the roles of insulin-like growth factors (IGF), hepatocyte growth factor (HGF) and transforming growth factor (TGF)-, in mouse tongue myogenesis were studied using an organ culture system of the mandible or tongue obtained from mouse embryos. It was found that IGF-I promotes the differentiation of tongue myoblasts. HGF plays an essential role in the migration and proliferation of tongue myogenic cells, and inhibits the differentiation of tongue myoblasts. TGF-, does not play an essential role in the proliferation of tongue myogenic cells, but does promote the early differentiation of tongue myoblasts. The role of IGF-I in the differentiation of tongue myoblasts, and that of HGF in the migration, proliferation and differentiation of tongue myogenic cells appear to be almost identical to their roles in the myogenesis of limb and cultured myogenic cell lines. However, the role of TGF-, in the proliferation and differentiation of tongue myogenic cells appears to be different from its role in the myogenesis of limb and cultured myogenic cell lines such as C2 and L6. [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] Recent advances in craniofacial morphogenesisDEVELOPMENTAL DYNAMICS, Issue 9 2006Yang Chai Abstract Craniofacial malformations are involved in three fourths of all congenital birth defects in humans, affecting the development of head, face, or neck. Tremendous progress in the study of craniofacial development has been made that places this field at the forefront of biomedical research. A concerted effort among evolutionary and developmental biologists, human geneticists, and tissue engineers has revealed important information on the molecular mechanisms that are crucial for the patterning and formation of craniofacial structures. Here, we highlight recent advances in our understanding of evo,devo as it relates to craniofacial morphogenesis, fate determination of cranial neural crest cells, and specific signaling pathways in regulating tissue,tissue interactions during patterning of craniofacial apparatus and the morphogenesis of tooth, mandible, and palate. Together, these findings will be beneficial for the understanding, treatment, and prevention of human congenital malformations and establish the foundation for craniofacial tissue regeneration. Developmental Dynamics 235:2353,2375, 2006. © 2006 Wiley-Liss, Inc. [source] Interpopulation differences in the mandible size of the coastal tiger beetle Lophyridia angulata associated with different sympatric speciesENTOMOLOGICAL SCIENCE, Issue 3 2004Aya SATOH Abstract The coastal tiger beetle Lophyridia angulata (Fabricius) co-occurs with one or two tiger beetle species at any one locality (in a sandy beach habitat) along the Japan Sea coast of Honshu, from eastern to southern Kyushu, and on Tanega-shima, an island south of Kyushu, in Japan. Lophyridia angulata displays sexual dimorphism in mandible length (the mandible is longer in females), and shows large interpopulation differences in mandible size. We analyzed variation in mandible length between L. angulata populations associated with three different sympatric species, and examined morphological differences that may have resulted from interaction with these other species. Lophyridia angulata showed a significant size shift towards larger mandibles in a population that co-occurred with Cicindela lewisii, which has a similar mandible length to that of L. angulata, as compared to a neighboring population of L. angulata that co-occurred with another species. This pattern may be interpreted as a type of character displacement associated with food resource competition. Males in L. angulata populations co-occurring with Chaetodera laetescripta showed little variation in mandible length, as compared to other populations. These males may experience some pressure from C. laetescripta and from conspecific females. We found no significant changes in mandible length or in size variation of L. angulata before and 20 years after the extinction of Abroscelis anchoralis at one site historically co-inhabited by both species; that is, we did not detect a character release over the 20 years. [source] Caries outcomes after orthodontic treatment with fixed appliances: do lingual brackets make a difference?EUROPEAN JOURNAL OF ORAL SCIENCES, Issue 3 2010M. H. Van Der Veen van der Veen MH, Attin R, Schwestka-Polly R, Wiechmann D. Caries outcomes after orthodontic treatment with fixed appliances: do lingual brackets make a difference? Eur J Oral Sci 2010; 118: 298,303.©2010 The Authors. Journal compilation © 2010 Eur J Oral Sci Orthodontic treatment with fixed appliances is considered a risk factor for the development of white spot caries lesions (WSL). Traditionally, brackets are bonded to the buccal surfaces. Lingual brackets are developing rapidly and have become more readily available. Buccal surfaces are considered to be more caries prone than lingual surfaces. Furthermore, lingual brackets are shaped to fit the morphology of the teeth and seal almost the entire surface. In the present study we tested the hypothesis that lingual brackets result in a lower caries incidence than buccal brackets. We tested this hypothesis using a split-mouth design where subjects were allocated randomly to a group receiving either buccal or lingual brackets on the maxillary teeth and the alternative bracket type in the mandible. The results indicate that buccal surfaces are more prone to WSL development, especially when WSL existed before treatment. The number of WSL that developed or progressed on buccal surfaces was 4.8 times higher than the number of WSL that developed or progressed on lingual surfaces. When measured using quantitative light-induced fluorescence (QLF), the increase in integrated fluorescence loss was 10.6 times higher buccally than lingually. We conclude that lingual brackets make a difference when caries lesion incidence is concerned. [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] | ||||||||||||||||||||||||||||||||||||||||