Missing Teeth and Prosthetic Treatment in Patients Treated at College of Dentistry, University of Dammam

Directory of Open Access Journals (Sweden)

Shaimaa M. Fouda

2017-01-01

Full Text Available The percentage of completely and partially edentulous patients and their prosthetic treatment at the Department of Substitutive Dental Sciences (SDS, College of Dentistry, University of Dammam, were investigated. Panoramic radiographs and medical records of adult patients (n=479, mean age 45.9 years, and range 25–96 years treated in 2011–2014 were examined. 6% of the patients were completely edentulous, 8% had single jaw edentulousness, and 74% were partially edentulous. Edentulousness was significantly correlated with age and the number of missing teeth was significantly higher among males (p<0.026. Diabetes was significantly associated with complete edentulousness, single edentulous jaw (p value 0.015, and partial edentulousness (p value 0.023. Kennedy class III was the most frequent class of partial edentulousness in single and/or both jaws (p=0.000. Patients having class I and/or class II were treated most often with removable partial dentures (RPD (p=0.000, while patients having class III were treated with fixed partial dentures (FPD. It was found that complete edentulousness increases in older age and the number of missing teeth was significantly higher among males. Kennedy class III was most common in both upper and lower jaw and was treated more often with FPD than with RPD.

A 15-year study of osseointegrated implants in the treatment of the edentulous jaw.

Science.gov (United States)

Adell, R; Lekholm, U; Rockler, B; Brånemark, P I

1981-12-01

Osseointegration implies a firm, direct and lasting connection between vital bone and screw-shaped titanium implants of defined finish and geometry-fixtures. Thus, there is no interposed tissue between fixture and bone. Osseointegration can only be achieved and maintained by a gentle surgical installation technique, a long healing time and a proper stress distribution when in function. During a 15-year period (1965-1980), 2768 fixtures were installed in 410 edentulous jaws of 371 consecutive patients. All patients were provided with facultatively removable bridges and were examined at continuous yearly controls. The surgical and prosthetic technique was developed and evaluated over a pilot period of 5 years. The results of standardized procedures applied on a consecutive clinical material with an observation time of 5-9 years were thought to properly reflect the potential of the method. In this group, 130 jaws were provided with 895 fixtures, and of these 81% of the maxillary and 91% of the mandibular fixtures remained stable, supporting bridges. In 89% of the maxillary and 100% of the mandibular cases, the bridges were continuously stable. During healing and the first year after connection of the bridge, the mean value for marginal bone loss was 1.5 mm. Thereafter only 0.1 mm was lost annually. The clinical results achieved with bridges on osseointegrated fixtures fulfill and exceed the demands set by the 1978 Harvard Conference on successful dental implantation procedures.

Cast Partial Denture versus Acrylic Partial Denture for Replacement of Missing Teeth in Partially Edentulous Patients

Directory of Open Access Journals (Sweden)

Pramita Suwal

2017-03-01

Full Text Available Aim: To compare the effects of cast partial denture with conventional all acrylic denture in respect to retention, stability, masticatory efficiency, comfort and periodontal health of abutments. Methods: 50 adult partially edentulous patient seeking for replacement of missing teeth having Kennedy class I and II arches with or without modification areas were selected for the study. Group-A was treated with cast partial denture and Group-B with acrylic partial denture. Data collected during follow-up visit of 3 months, 6 months, and 1 year by evaluating retention, stability, masticatory efficiency, comfort, periodontal health of abutment. Results: Chi-square test was applied to find out differences between the groups at 95% confidence interval where p = 0.05. One year comparison shows that cast partial denture maintained retention and stability better than acrylic partial denture (p< 0.05. The masticatory efficiency was significantly compromising from 3rd month to 1 year in all acrylic partial denture groups (p< 0.05. The comfort of patient with cast partial denture was maintained better during the observation period (p< 0.05. Periodontal health of abutment was gradually deteriorated in all acrylic denture group (p

The edentulous mandible opposing maxillary natural teeth: treatment considerations utilizing implant overdentures.

Science.gov (United States)

Winkler, S; Monasky, G E

1993-01-01

The restoration of the edentulous mandible opposing all or part of the maxillary natural dentition with implant overdentures is described. There are many situations in which the maxillary teeth opposing an edentulous mandible can and should be retained. Mandibular implant overdentures can be utilized as long as health considerations, morphologic features of the resorbed mandible, and maxillomandibular jaw relationships are satisfactory.

Restoration-Guided Implant Rehabilitation of the Complex Partial Edentulism: a Clinical Report

Directory of Open Access Journals (Sweden)

Nikitas Sykaras

2010-01-01

Full Text Available Background: The hard and soft tissue deficiency is a limiting factor for the prosthetic restoration and any surgical attempt to correct the anatomic foundation needs to be precisely executed for optimal results. The purpose of this paper is to describe the clinical steps that are needed to confirm the treatment plan and allow its proper execution.Methods: Team work and basic principles are emphasized in a step-by-step description of clinical methods and techniques. This clinical report describes the interdisciplinary approach in the rehabilitation of a partially edentulous patient. The importance of the transitional restoration which sets the guidelines for the proper execution of the treatment plan is especially emphasized along with all the steps that have to be followed.Results: The clinical report describes the diagnostic arrangement of teeth, the ridge augmentation based on the diagnostic evaluation of the removable prosthesis, the implant placement with a surgical guide in the form of the removable partial denture duplicate and finally the special 2-piece design of the final fixed prosthesis.Conclusions: Clinical approach and prosthesis design described above offers a predictable way to restore partial edentulism with a fixed yet retrievable prosthesis, restoring soft tissue and teeth and avoiding an implant supported overdenture.

Dual jaw treatment of edentulism using implant-supported monolithic zirconia fixed prostheses.

Science.gov (United States)

Altarawneh, Sandra; Limmer, Bryan; Reside, Glenn J; Cooper, Lyndon

2015-01-01

This case report describes restoration of the edentulous maxilla and mandible with implant supported fixed prostheses using monolithic zirconia, where the incisal edges and occluding surfaces were made of monolithic zirconia. Edentulism is a debilitating condition that can be treated with either a removable or fixed dental prosthesis. The most common type of implant-supported fixed prosthesis is the metal acrylic (hybrid), with ceramo-metal prostheses being used less commonly in complete edentulism. However, both of these prostheses designs are associated with reported complications of screw loosening or fracture and chipping of acrylic resin and porcelain. Monolithic zirconia implant-supported fixed prostheses have the potential for reduction of such complications. In this case, the CAD/CAM concept was utilized in fabrication of maxillary and mandibular screw-retained implant-supported fixed prostheses using monolithic zirconia. Proper treatment planning and execution coupled with utilizing advanced technologies contributes to highly esthetic results. However, long-term studies are required to guarantee a satisfactory long-term outcome of this modality of treatment. This case report describes the clinical and technical procedures involved in fabrication of maxillary and mandibular implant-supported fixed prostheses using monolithic zirconia as a treatment of edentulism, and proposes the possible advantages associated with using monolithic zirconia in eliminating dissimilar interfaces in such prostheses that are accountable for the most commonly occurring technical complication for these prostheses being chipping and fracture of the veneering material. © 2015 Wiley Periodicals, Inc.

Implant and root supported overdentures - a literature review and some data on bone loss in edentulous jaws.

Science.gov (United States)

Carlsson, Gunnar E

2014-08-01

To present a literature review on implant overdentures after a brief survey of bone loss after extraction of all teeth. Papers on alveolar bone loss and implant overdentures have been studied for a narrative review. Bone loss of the alveolar process after tooth extraction occurs with great individual variation, impossible to predict at the time of extraction. The simplest way to prevent bone loss is to avoid extraction of all teeth. To keep a few teeth and use them or their roots for a tooth or root-supported overdenture substantially reduces bone loss. Jaws with implant-supported prostheses show less bone loss than jaws with conventional dentures. Mandibular 2-implant overdentures provide patients with better outcomes than do conventional dentures, regarding satisfaction, chewing ability and oral-health-related quality of life. There is no strong evidence for the superiority of one overdenture retention-system over the others regarding patient satisfaction, survival, peri-implant bone loss and relevant clinical factors. Mandibular single midline implant overdentures have shown promising results but long-term results are not yet available. For a maxillary overdenture 4 to 6 implants splinted with a bar provide high survival both for implants and overdenture. In edentulous mandibles, 2-implant overdentures provide excellent long-term success and survival, including patient satisfaction and improved oral functions. To further reduce the costs a single midline implant overdenture can be a promising option. In the maxilla, overdentures supported on 4 to 6 implants splinted with a bar have demonstrated good functional results.

Implant and root supported overdentures - a literature review and some data on bone loss in edentulous jaws

Science.gov (United States)

2014-01-01

PURPOSE To present a literature review on implant overdentures after a brief survey of bone loss after extraction of all teeth. MATERIALS AND METHODS Papers on alveolar bone loss and implant overdentures have been studied for a narrative review. RESULTS Bone loss of the alveolar process after tooth extraction occurs with great individual variation, impossible to predict at the time of extraction. The simplest way to prevent bone loss is to avoid extraction of all teeth. To keep a few teeth and use them or their roots for a tooth or root-supported overdenture substantially reduces bone loss. Jaws with implant-supported prostheses show less bone loss than jaws with conventional dentures. Mandibular 2-implant overdentures provide patients with better outcomes than do conventional dentures, regarding satisfaction, chewing ability and oral-health-related quality of life. There is no strong evidence for the superiority of one overdenture retention-system over the others regarding patient satisfaction, survival, peri-implant bone loss and relevant clinical factors. Mandibular single midline implant overdentures have shown promising results but long-term results are not yet available. For a maxillary overdenture 4 to 6 implants splinted with a bar provide high survival both for implants and overdenture. CONCLUSION In edentulous mandibles, 2-implant overdentures provide excellent long-term success and survival, including patient satisfaction and improved oral functions. To further reduce the costs a single midline implant overdenture can be a promising option. In the maxilla, overdentures supported on 4 to 6 implants splinted with a bar have demonstrated good functional results. PMID:25177466

Reference-based digital concept to restore partially edentulous patients following an immediate loading protocol: a pilot study

NARCIS (Netherlands)

Tahmaseb, A.; de Clerck, R.; Eckert, S.; Wismeijer, D.

2011-01-01

PURPOSE: To describe the use of a computer-aided three-dimensional planning protocol in combination with previously placed reference elements and computer-aided design/computer-assisted manufacture (CAD/CAM) technology to restore the partially edentulous patient. MATERIALS AND METHODS: Mini-implants

Comparative clinical evaluation of removable partial dentures made of two different materials in Kennedy Applegate class II partially edentulous situation.

Science.gov (United States)

Hundal, Maninder; Madan, Rajesh

2015-12-01

Cast Chromium Cobalt alloy has been the material of choice for fabricating Removable Partial Dentures (RPDs) but has certain drawbacks. Newer materials like the flexible Nylon based Super Polyamide have been introduced to overcome these drawbacks. The present study has compared the above two materials for nine clinical parameters. The study was carried out on 30 patients presenting with a Kennedy Applegate class II partially edentulous situation who were divided into two equal groups and clinically assessed. Statistically significant results were obtained in favor of flexible RPDs, in the parameters of 'aesthetics' and 'overall patient satisfaction'. Both groups showed more or less similar values for 'frequency of fracture of the prosthesis during usage' with the incidence being slightly higher for patients wearing the cast RPDs. The clinical parameters of 'oral soft tissue tolerance', 'gingival health', 'periodontal health' and 'adaptability in areas with undercut' were statistically at par for all the 30 patients thus suggesting the comparable biocompatibility of the two materials. The highlight of this study was the relative ease in fabrication of the flexible RPDs as compared to the cast RPDs. Based on the favorable clinical results of this study, it can be summarized that the flexible RPDs is a viable alternative to cast RPDs in Kennedy Applegate class II partially edentulous situation in the short term.

Retrospective comparative ten-year study of cumulative survival rates of remaining teeth in large edentulism treated with implant-supported fixed partial dentures or removable partial dentures.

Science.gov (United States)

Yamazaki, Seiya; Arakawa, Hikaru; Maekawa, Kenji; Hara, Emilio Satoshi; Noda, Kinji; Minakuchi, Hajime; Sonoyama, Wataru; Matsuka, Yoshizo; Kuboki, Takuo

2013-07-01

This study aimed to compare the survival rates of remaining teeth between implant-supported fixed dentures (IFDs) and removable partial dentures (RPDs) in patients with large edentulous cases. The second goal was to assess the risk factors for remaining tooth loss. The study subjects were selected among those who received prosthodontic treatment at Okayama University Dental Hospital for their edentulous space exceeding at least four continuous missing teeth. Twenty-one patients were included in the IFD group and 82 patients were included in the RPD group. Survival rates of remaining teeth were calculated in three subcategories: (1) whole remaining teeth, (2) adjacent teeth to intended edentulous space, and (3) opposing teeth to intended edentulous space. The ten-year cumulative survival rate of the whole remaining teeth was significantly higher in the IFD group (40.0%) than in the RPD group (24.4%). On the other hand, there was no significant difference between two groups in the survival rate of teeth adjacent or opposing to intended edentulous space. A Cox proportional hazard analysis revealed that RPD restoration and gender (male) were the significant risk factors for remaining tooth loss (whole remaining teeth). These results suggest that IFD treatment can reduce the incidence of remaining tooth loss in large edentulous cases. Copyright © 2013 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.

Prosthodontic rehabilitation of completely edentulous patient with partial glossectomy

Directory of Open Access Journals (Sweden)

Aditi Garg

2016-01-01

Full Text Available Oral cancer accounts for about 40% of all cancers inflicting the human beings. Those involving the tongue results in mild to severe deficiencies of phonation, deglutition, mastication, and taste depending upon the degree and extent tissues involved. Often rehabilitation of such patient is a challenge for the prosthodontist and involves a careful observation and evaluation of the residual oral function and ways to restore them. This article presents a case report of prosthodontic rehabilitation completely edentulous patient, who underwent partial glossectomy following surgical resection of the squamous cell carcinoma involving left lateral borders of the tongue. An attempt was made to restore the comfort and function of the patient with the help of palatal augmentation prosthesis, with additional assistance through speech therapy and simple oral exercises.

Digital versus conventional implant impressions for partially edentulous arches: An evaluation of accuracy.

Science.gov (United States)

Marghalani, Amin; Weber, Hans-Peter; Finkelman, Matthew; Kudara, Yukio; El Rafie, Khaled; Papaspyridakos, Panos

2018-04-01

To the authors' knowledge, while accuracy outcomes of the TRIOS scanner have been compared with conventional impressions, no available data are available regarding the accuracy of digital scans with the Omnicam and True Definition scanners versus conventional impressions for partially edentulous arches. The purpose of this in vitro study was to compare the accuracy of digital implant scans using 2 different intraoral scanners (IOSs) with that of conventional impressions for partially edentulous arches. Two partially edentulous mandibular casts with 2 implant analogs with a 30-degree angulation from 2 different implant systems (Replace Select RP; Nobel Biocare and Tissue level RN; Straumann) were used as controls. Sixty digital models were made from these 2 definitive casts in 6 different groups (n=10). Splinted implant-level impression procedures followed by digitization were used to produce the first 2 groups. The next 2 groups were produced by digital scanning with Omnicam. The last 2 groups were produced by digital scanning with the True Definition scanner. Accuracy was evaluated by superimposing the digital files of each test group onto the digital file of the controls with inspection software. The difference in 3-dimensional (3D) deviations (median ±interquartile range) among the 3 impression groups for Nobel Biocare was statistically significant among all groups (P3D deviations among the 3 impression groups for Straumann was statistically significant among all groups (P=.003), except for the conventional impression (22 ±5 μm) and True Definition (17 ±5 μm) groups; the median ±interquartile range for the Omnicam group was 26 ±15 μm. The difference in 3D deviations between the 2 implant systems was significant for the Omnicam (P=.011) and conventional (Pimpression techniques but not for the True Definition technique (P=.247). Within the limitations of this study, both the impression technique and the implant system affected accuracy. The True

Bone augmentation followed by implant surgery in the edentulous mandible: a systematic review

NARCIS (Netherlands)

de Groot, R. J.; Oomens, M. A. E. M.; Forouzanfar, T.; Schulten, E. A. J. M.

2018-01-01

Long-standing loss of natural teeth in the mandible can lead to severe jaw atrophy and even mandibular fracture. There is no consensus on the best preprosthetic surgical treatment to reconstruct the atrophic edentulous mandible. The purpose of this review is to provide an overview of the existing

Comparison of Treatment Outcomes in Partially Edentulous Patients with Implant-Supported Fixed Prostheses and Removable Partial Dentures.

Science.gov (United States)

Nogawa, Toshifumi; Takayama, Yoshiyuki; Ishida, Keita; Yokoyama, Atsuro

The aim of this study was to compare masticatory performance, occlusal force, and oral health-related quality of life (OHRQoL) in patients with mandibular distal-extension edentulism between those with implant-supported fixed prostheses (ISFPs) and those with removable partial dentures (RPDs), and to evaluate relationships among them. Subjects were recruited from patients using ISFPs or RPDs for mandibular distal-extension edentulism. Masticatory performance was evaluated based on the glucose extracted from chewed gummy jelly. Occlusal force was measured with a pressure-sensitive sheet, and data were subjected to computer analysis. The Japanese version of the Oral Health Impact Profile (OHIP-J) was used to evaluate OHRQoL. The masticatory performance, occlusal force, and OHIP-J scores of the ISFP and RPD groups were compared using the Wilcoxon rank-sum test. The relationships among the variables were analyzed using the Spearman rank correlation coefficient test. Multivariate logistic regression analysis was employed with the OHIP-J score as a dependent variable. Nineteen patients with ISFPs and 25 patients with RPDs participated in this study. No significant difference was observed between the two groups with regard to masticatory performance and occlusal force. The OHIP-J score was significantly lower in the ISFP group than in the RPD group. The OHIP-J score had no significant correlation with masticatory performance, but was significantly correlated with occlusal force and the prosthetic method. Multivariate logistic regression analysis showed that younger age, RPDs, and lower occlusal force were significantly associated with a higher OHIP-J summary score. The present results suggest that the difference in masticatory performance and occlusal force between ISFPs and RPDs is small, but ISFPs are superior to RPDs with regard to OHRQoL in patients with mandibular distal-extension edentulism. In addition, there appears to be a slight correlation between the OHIP

A Survey of Removable Partial Denture (RPD Retentive Elements in Relation to Type of Edentulism and Abutment Teeth in Commercial Laboratories in Athens

Directory of Open Access Journals (Sweden)

Michael Sotiriou

2014-01-01

Full Text Available Objective. The aim of this survey was to record removable partial denture (RPD retentive elements and abutment teeth in partially edentulous patients, identified in commercial laboratories in Athens, Greece. Material and Methods. 628 master casts with the corresponding cast metal frameworks used in the construction of RPDs were evaluated. Casts were photographed to identify the number and position of existing teeth, the partial edentulism class and the retentive elements. Prevalence tables and the x2 test were used for the statistical analysis of the collected data (α=.05. Results. There were 276 maxillary (43.9% and 352 (56.1% mandibular casts. Maxillary edentulism entailed almost a total absence of right third molars in 96.7% and left third molars 96.0% of casts, with lower rates for the first and second molars. Edentulism in the posterior mandible presented a similar pattern. The most profound findings concerning retentive elements were: 91.9% of the retainers used were clasps and the remaining 8.1% were attachments. Of the clasps used, 48.9% were of the Roach Τ type, a finding more common in Kennedy Class I as compared to other Kennedy Classes (p<0.01. The circumferential clasps accounted for 19.3% of the total clasps used, and it was less frequently presented (8.8% in Kennedy I Classes (p<0.01. Conclusions. Roach clasps were used in the majority of cases whereas RPI clasps and attachments were rarely used.

Application of FDM three-dimensional printing technology in the digital manufacture of custom edentulous mandible trays

Science.gov (United States)

Chen, Hu; Yang, Xu; Chen, Litong; Wang, Yong; Sun, Yuchun

2016-01-01

The objective was to establish and evaluate a method for manufacture of custom trays for edentulous jaws using computer aided design and fused deposition modeling (FDM) technologies. A digital method for design the custom trays for edentulous jaws was established. The tissue surface data of ten standard mandibular edentulous plaster models, which was used to design the digital custom tray in a reverse engineering software, were obtained using a 3D scanner. The designed tray was printed by a 3D FDM printing device. Another ten hand-made custom trays were produced as control. The 3-dimentional surface data of models and custom trays was scanned to evaluate the accuracy of reserved impression space, while the difference between digitally made trays and hand-made trays were analyzed. The digitally made custom trays achieved a good matching with the mandibular model, showing higher accuracy than the hand-made ones. There was no significant difference of the reserved space between different models and its matched digitally made trays. With 3D scanning, CAD and FDM technology, an efficient method of custom tray production was established, which achieved a high reproducibility and accuracy. PMID:26763620

A Survey of Removable Partial Denture (RPD) Retentive Elements in Relation to the Type of Edentulism and Abutment Teeth Found in Commercial Laboratories, Athens, Greece

Science.gov (United States)

Sotiriou, Michael; Zissis, Alcibiades

2014-01-01

Objective The aim of this survey was to record removable partial denture (RPD) retentive elements and abutment teeth in partially edentulous patients, identified in commercial laboratories in Athens, Greece. Material and Methods 628 master casts with the corresponding cast metal frameworks used in the construction of RPDs were evaluated. Casts were photographed to identify the number and position of existing teeth, the partial edentulism class and the retentive elements. Prevalence tables and the x2 test were used for the statistical analysis of the collected data (α=.05). Results There were 276 maxillary (43.9%) and 352 (56.1%) mandibular casts. Maxillary edentulism entailed almost a total absence of right third molars in 96.7% and left third molars 96.0% of casts, with lower rates for the first and second molars. Edentulism in the posterior mandible presented a similar pattern. The most profound findings concerning retentive elements were: 91.9% of the retainers used were clasps and the remaining 8.1% were attachments. Of the clasps used, 48.9% were of the Roach Τ type, a finding more common in Kennedy Class I as compared to other Kennedy Classes (p<0.01). The circumferential clasps accounted for 19.3% of the total clasps used, and it was less frequently presented (8.8%) in Kennedy I Classes (p<0.01). Conclusions Roach clasps were used in the majority of cases whereas RPI clasps and attachments were rarely used. PMID:27688367

Effects of Impression Material, Impression Tray Type, and Type of Partial Edentulism on the Fit of Cobalt-Chromium Partial Denture Frameworks on Initial Clinical Insertion: A Retrospective Clinical Evaluation.

Science.gov (United States)

Baig, Mirza Rustum; Akbar, Jaber Hussain; Qudeimat, Muawia; Omar, Ridwaan

2018-02-15

To evaluate the effects of impression material, impression tray type, and type of partial edentulism (ie, Kennedy class) on the accuracy of fit of cobalt-chromium (Co-Cr) partial removable dental prostheses (PRDP) in terms of the number of fabricated frameworks required until the attainment of adequate fit. Electronic case documentations of 120 partially edentulous patients provided with Co-Cr PRDP treatment for one or both arches were examined. Statistical analyses of data were performed using analysis of variance and Tukey honest significant difference test to compare the relationships between the different factors and the number of frameworks that needed to be fabricated for each patient (α = .05). Statistical analysis of data derived from 143 records (69 maxillary and 74 mandibular) revealed no significant correlation between impression material, tray type, or Kennedy class and the number of construction attempts for the pooled or individual arch data (P ≥ .05). In PRDP treatment, alginate can be chosen as a first-choice material, and metal stock trays can be a preferred option for making final impressions to fabricate Co-Cr frameworks.

Oral health related quality-of-life outcomes of partially edentulous patients treated with implant-supported single crowns or fixed partial dentures.

Science.gov (United States)

AlZarea, Bader K

2017-05-01

Oral health-related quality of life (OHRQoL) is afflicted by different variables. Limited information is available regarding the impact of different phases of implant therapy on OHRQoL of edentulous patients. This study was carried out to assess the OHRQoL of patients treated with implant-supported single crowns or fixed partial dentures. A total of 79 healthy partially edentulous subjects needing implant therapy were incorporated in this study. Before placement of the implants, the subjects were instructed to fill the original version of OHIP questionnaire. Subsequently patients received titanium oral implants of the ITI® Dental Implant System. After 1st, 2nd and 3rd year of implant placement, patients filled the same OHIP-49 questionnaire. In this manner the impact of implant therapy on OHRQoL by putting in comparison pre- and post-treatment OHIP-49 scores was assessed. Statistical analyses were performed using Statistical Package for the Social Science software (SPSS, version 22, Chicago, IL, USA). Paired t test and Unpaired t test were performed and a statistical significance was set at 5% level of significance ( p disability, psychological disability, social disability were significantly decreased from baseline to 1st year ( p 0.05). All variables were also significantly decreased from baseline to 2nd year and 3rd year ( p 0.05). Patients aged less than 60 years and more than 60 years of age groups differed significantly with respect to OHIP scores measured at 1st year, 2nd year and at 3rd year of implant placement ( p Oral health-related quality-of-life.

Actinobacillus actinamycetemcomitans-associated peri-implantitis in an edentulous patient - A case report

NARCIS (Netherlands)

van Winkelhoff, AJ; Wolf, JWA

Background: Peri-implantitis is a risk factor for implant loss. Late bacterial infection of the peri-implant tissues and loss of alveolar bone in edentulous patients is caused by commensal oral anaerobic bacteria. In partially edentulous patients, Porphyromonas gingivalis and occasionally

Oral Rehabilitation of Adult Edentulous Siblings Severely Lacking Alveolar Bone Due to Ectodermal Dysplasia: A Report of 2 Clinical Cases and a Literature Review.

Science.gov (United States)

Wu, Yiqun; Zhang, Chenping; Squarize, Cristiane H; Zou, Duohong

2015-09-01

The oral conditions of adult edentulous patients with ectodermal dysplasia (ED) often lead to decreased physical and psychological health, and the negative effects can become as extreme as social and psychological isolation. However, restoring oral function of adult edentulous patients with ED using zygomatic implants (ZIs) or conventional implants (CIs) remains challenging for dentists because of the severe atrophy of these patients' alveolar ridges. This report describes 2 cases of adult edentulous siblings with ED; they exhibited severe alveolar bone atrophy and were treated with ZIs and CIs as bases to augment the bone in their anterior jaws. For these patients, bone augmentation was completed with an autogenous fibular graft. Although there was mild evidence of bone graft resorption in the maxilla, the bone augmentation procedures were successful in the 2 patients. Effective osseointegration of the implants was obtained. After placement, the functional and esthetic results of the oral rehabilitation were acceptable. More importantly, restoration of the patients' oral function enhanced their self-confidence and self-esteem. Therefore, restoring oral function in adult patients with ED and edentulous jaws using ZIs and CIs as the bases for bone augmentation is an effective approach. Crown Copyright © 2015. Published by Elsevier Inc. All rights reserved.

Implant rehabilitation of partial maxillectomy edentulous patien

Directory of Open Access Journals (Sweden)

Mahesh E Gowda

2013-01-01

Full Text Available Edentulous patients with maxillectomy defects present a significant challenge for prosthetic rehabilitation and the adaptive capabilities of the patient as retention is highly compromised. Hence, the option of using endosseous implants to increase obturator retention has been used. A patient of mucormycosis of the left maxilla was treated with surgical excision. After satisfactory healing, definitive implant supported magnet retained prosthesis was fabricated for the patient. Implants with magnetic units offer a practical method of improving the retention of obturators provided acceptable prosthetic protocols are followed for the rehabilitation.

Implant rehabilitation of partial maxillectomy edentulous patient

Science.gov (United States)

Gowda, Mahesh E.; Mohan, Murali S.; Verma, Kamal; Roy, I. D.

2013-01-01

Edentulous patients with maxillectomy defects present a significant challenge for prosthetic rehabilitation and the adaptive capabilities of the patient as retention is highly compromised. Hence, the option of using endosseous implants to increase obturator retention has been used. A patient of mucormycosis of the left maxilla was treated with surgical excision. After satisfactory healing, definitive implant supported magnet retained prosthesis was fabricated for the patient. Implants with magnetic units offer a practical method of improving the retention of obturators provided acceptable prosthetic protocols are followed for the rehabilitation. PMID:24124314

Socio-demographic factors and edentulism: the Nigerian experience

Directory of Open Access Journals (Sweden)

Akeredolu Patricia

2004-11-01

Full Text Available Abstract Background The rate of total edentulism is said to be increasing in developing countries and this had been attributed mainly to the high prevalence of periodontal diseases and caries. Several reports have shown that non-disease factors such as attitude, behavior, dental attendance, characteristics of health care systems and socio-demographic factors play important roles in the aetiopathogenesis of edentulism. The aim of this study was to assess the relationship between socio-demographic factors and edentulism. Methods A total of 152 patients made up of 80 (52.6% males and 72 (47.4% females who presented in two prosthetic clinics located in an urban and a rural area were included in the study. The relationship between gender, age, socio-economic status and edentulism in this study population was established. Results No significant relationship between gender and denture demand was noted in the study. The demand for complete dentures increased with age while the demand for removable partial dentures also increased with age until the 3rd decade and then started to decline. A significant relationship was found between denture demand and the level of education with a higher demand in lower educational groups (p Conclusions The findings in this study revealed a significant relationship between socio-demographic variables and edentulism with age, educational level and socio-economic status playing vital roles in edentulism and denture demand.

Follicular cyst of the jaw developing into a keratocyst in a patient with unrecognized Gorlin-Goltz syndrome.

Science.gov (United States)

Longobardi, Gianluigi; Diana, Giovanni; Poddi, Valentina; Pagano, Immacolata

2010-05-01

Gorlin-Goltz (GG) syndrome is an inherited autosomal dominant condition. Its diagnosis may be clinically confirmed by checking either major or minor signs that define the diagnostic criteria. It may occur that, although GG syndrome is a well-known condition, only the specific symptom could be observed by different specialists. Therefore, the patient cannot be placed into an always complex clinical panel. We introduce an example in this report. Throughout a 20-year clinical history characterized by the lack of proper diagnosis and missed follow-up operations, a patient with GG syndrome underwent partial amputation of the jaw after severe complications. A 52-year-old man required an implant-prosthetic rehabilitation since becoming edentulous after a partial resection of the jaw due to a keratocyst, which was later reconstructed through a free fibula flap. The observation of a typical phenotype and various symptoms that succeeded for longer than 20 years, with anamnestic evaluation and clinical examination, led us to suspect a complex pathologic condition such as GG syndrome, which was not previously considered, although the patient had undergone several polyspecialistic evaluations. Diagnosis has been eventually confirmed by a genetic study, which was always mandatory. The simultaneous presence of muscular and skeletal malformations, basocellular nevi, and multiple cysts of the jaw can represent signs linking to a condition such as GG syndrome. There are many syndromes involving the head and neck region, and specialists are supposed to be alerted when faced with similar typical expressions associated with a characteristic soma so as to avoid delays in diagnosing the syndrome.

Trueness and precision of digital impressions obtained using an intraoral scanner with different head size in the partially edentulous mandible.

Science.gov (United States)

Hayama, Hironari; Fueki, Kenji; Wadachi, Juro; Wakabayashi, Noriyuki

2018-03-01

It remains unclear whether digital impressions obtained using an intraoral scanner are sufficiently accurate for use in fabrication of removable partial dentures. We therefore compared the trueness and precision between conventional and digital impressions in the partially edentulous mandible. Mandibular Kennedy Class I and III models with soft silicone simulated-mucosa placed on the residual edentulous ridge were used. The reference models were converted to standard triangulated language (STL) file format using an extraoral scanner. Digital impressions were obtained using an intraoral scanner with a large or small scanning head, and converted to STL files. For conventional impressions, pressure impressions of the reference models were made and working casts fabricated using modified dental stone; these were converted to STL file format using an extraoral scanner. Conversion to STL file format was performed 5 times for each method. Trueness and precision were evaluated by deviation analysis using three-dimensional image processing software. Digital impressions had superior trueness (54-108μm), but inferior precision (100-121μm) compared to conventional impressions (trueness 122-157μm, precision 52-119μm). The larger intraoral scanning head showed better trueness and precision than the smaller head, and on average required fewer scanned images of digital impressions than the smaller head (pdigital impressions. Digital impressions are partially comparable to conventional impressions in terms of accuracy; the use of a larger scanning head may improve the accuracy for removable partial denture fabrication. Copyright © 2018 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.

Alveolar ridge atrophy related to facial morphology in edentulous patients

Directory of Open Access Journals (Sweden)

Kuć J

2017-09-01

Full Text Available Joanna Kuć,1 Teresa Sierpińska,2 Maria Gołębiewska1 1Department of Prosthodontics, 2Department of Dental Technology, Medical University of Bialystok, Bialystok, Poland Objectives: The morphology of the alveolar process determines the retention and stability of prosthetic restorations, thereby determining the result of the therapy. Considering that the edentulous jaws may be affected by the atrophy process, it was hypothesized that the morphology of the alveolar process of the maxilla may be dependent on the anterior facial height and anatomy of the mandible. Subjects and methods: Twenty-five healthy edentulous Caucasian individuals were randomly chosen. Each subject underwent a lateral cephalogram before and after prosthetic rehabilitation. During exposition, newly made prostheses were placed in the patient’s mouth. Teeth remained in maximal intercuspidation. Morphological parameters were evaluated according to the Ricketts, McNamara, and Tallgren’s method. Results: An inversely proportional association was observed between patient age and the distal part of the maxilla. A statistically significant connection was noted between the vertical dimension of alveolar ridge and anterior total and lower facial height conditioned by prosthetic rehabilitation. Conclusion: The height of the lateral part of the alveolar ridge of the maxilla remains in connection with the anterior total and lower facial height obtained in the course of prosthetic rehabilitation. The vertical dimension of the alveolar ridge of the maxilla seems to be in close relationship with the morphology of the lower jaw. Keywords: anterior facial height, cephalometric analysis, complete dentures, vertical occlusal dimension

Individual- and community-level social gradients of edentulousness.

Science.gov (United States)

Ito, Kanade; Aida, Jun; Yamamoto, Tatsuo; Ohtsuka, Rika; Nakade, Miyo; Suzuki, Kayo; Kondo, Katsunori; Osaka, Ken

2015-03-11

Community-level factors as well as individual-level factors affect individual health. To date, no studies have examined the association between community-level social gradient and edentulousness. The aim of this study was to investigate individual- and community-level social inequalities in edentulousness and to determine any explanatory factors in this association. We analyzed the data from the Japan Gerontological Evaluation Study (JAGES). In 2010-2012, 112,123 subjects aged 65 or older responded to the questionnaire survey (response rate = 66.3%). Multilevel logistic regression analysis was applied to determine the association between community-level income and edentulousness after accounting for individual-level income and demographic covariates. Then, we estimated the probability of edentulousness by individual- and community-level incomes after adjusted for covariates. Of 79,563 valid participants, the prevalence of edentulousness among 39,550 men (49.7%) and 40,013 women (50.3%) were both 13.8%. Living in communities with higher mean incomes and having higher individual-level incomes were significantly associated with a lower risk of edentulousness (odds ratios [ORs] by 10,000 USD increments were 0.37 (95% confidence interval [CI] [0.22-0.63]) for community-level and 0.85 (95% CI [0.84-0.86]) for individual-level income). Individual- and community-level social factors, including density of dental clinics, partially explained the social gradients. However, in the fully adjusted model, both community- and individual-level social gradients of edentulousness remained significant (ORs = 0.43 (95% CI [0.27-0.67]) and 0.90 (95% CI [0.88-0.91]), respectively). One standard deviation changes in community- and individual-level incomes were associated with 0.78 and 0.84 times lower odds of edentulousness, respectively. In addition, compared to men, women living in communities with higher average incomes had a significantly lower risk of edentulousness (p-value for

The influence of hyperthyroidism on implant restoration treatment outcome

Directory of Open Access Journals (Sweden)

Suhandi Sidjaja

2006-09-01

Full Text Available There is limited information about bone implant restoration treatment on edentulous patient with hyperthyroidism. This clinical report is presenting the making of dental bone implant restoration on patient with hyperthyroidism history. A 60 years old male patient with hyperthyroidism came to Prosthodontic Clinic Faculty of Dentistry University of Indonesia to improve his ailing denture. After comprehensive evaluation we treated the patient with Implant-Tissue-Supported Overdenture (4 Implants for rehabilitating upper edentulous jaw, and 2 Implant-Tooth-Supported Fixed Partial Denturesfor rehabilitating Kennedy class II lower edentulous jaw respectively. Short term clinical and radiographic evaluation based on Buser’s criteria showed positive result. (Med J Indones 2006; 15:191-5Keywords: Hyperthyroidsm, implant restoration

Ten-year survival rates of teeth adjacent to treated and untreated posterior bounded edentulous spaces.

Science.gov (United States)

Aquilino, S A; Shugars, D A; Bader, J D; White, B A

2001-05-01

Failure to replace a single missing posterior tooth may lead to a variety of dental problems, which may ultimately result in tooth loss. However, little is known about the fate of the adjacent teeth if a missing posterior tooth is not replaced. This retrospective study evaluated the survival of teeth adjacent to treated and untreated posterior bounded edentulous spaces. Data were obtained from electronic treatment records from the Kaiser Permanente Dental Care Program, Portland, Ore. A final sample of 317 patients who met the study inclusion criteria was identified. Each bounded edentulous space was placed in 1 of 3 treatment categories: untreated, restored with a fixed partial denture, or restored with a removable partial denture. Subsequent treatment and the status of the teeth adjacent to the bounded edentulous space were followed through December 1999. Ten-year Kaplan-Meier survival estimates were generated for each treatment group, and differences in survival were evaluated with the log-rank chi-square test (alpha=.05). There was a significant difference in survival among the 3 treatment categories (P=.005). Spaces restored with a fixed partial denture had longer 10-year survival estimates (92%) than those that remained untreated (81%). Spaces restored with a removable partial denture had the poorest 10-year survival rate (56%). Under the conditions and selection bias associated with this retrospective study, the survival of teeth adjacent to a single posterior edentulous space was negatively associated with removable partial denture placement compared with no treatment or the use of a fixed partial denture.

Mouth floor enlargements related to the sublingual glands in edentulous or partially edentulous patients: a microscopic study Tumefações do soalho bucal relacionadas às glândulas sublinguais em pacientes edêntulos ou parcialmente edêntulos: estudo microscópico

Directory of Open Access Journals (Sweden)

Liogi Iwaki Filho

2006-08-01

Full Text Available Mouth floor enlargements (MFE are observed in edentulous and partially edentulous patients, impairing denture fitting, and have recently been described in the literature as hyperplasias of the sublingual glands. OBJECTIVE: This study aims at describing the microscopic aspects of MFE that contribute to their final diagnosis. METHODS: Twenty-four specimens were surgically removed from the enlarged mouth floor of 19 patients (15 females and 4 males. Patient age ranged from 48 to 74 years, with a mean of 57 years. The main surgical indication was to permit or improve the fitting of dentures. Six patients were completely edentulous and 13 were partially edentulous. The material was processed for microscopic examination and stained with hematoxylin-eosin, Mallory's trichrome and periodic-acid Schiff (PAS. RESULTS AND CONCLUSIONS: The epithelium of the mouth floor was normal in 17 cases, hyperplastic in 4 and atrophic in 3. Six of the 24 sublingual glands removed were microscopically normal, while the other specimens presented acinar atrophy with hyperplasia of duct-like structures. Interstitial fibrosis was observed in 18 cases and was accompanied by adipose tissue infiltration in 15. Decreased lymphoid tissue was observed in 16 samples and oncocytosis was present in 5 cases. We suggest that MFE in edentulous or partially edentulous patients should be considered as an entity for the text books.Tumefações do soalho bucal (TSB são observadas em pacientes edêntulos ou parcialmente edêntulos, prejudicando a adaptação de próteses, e têm sido descritas recentemente na literatura como hiperplasias das glândulas sublinguais. OBJETIVO: O objetivo desse estudo é descrever os aspectos microscópicos das TSB a fim de contribuir para o seu diagnóstico final. MATERIAL E MÉTODOS: Foram removidos cirurgicamente 24 espécimes de 19 pacientes (15 mulheres e 4 homens que possuíam TSB. A idade variou de 48 a 74 anos, com média de 57 anos. A principal

Correlation of pontic design and partial edentulous areas: A one year cross sectional study

Directory of Open Access Journals (Sweden)

Nikzad S.

2008-12-01

Full Text Available "nBackground and Aim: By definition, pontic is an artificial replacement of missing tooth (teeth which is essentially used to establish function and esthetics. In order to this fact that, pontic(s is not completely the same as tooth (teeth to be replaced, it may not be concern as a simple type of restoration to achieve the best result, it must be design from the esthetically and hygienically point of view as well as comfort, demand and tissue health of patient. The main purpose of this study is to investigate the pontic designs and their relationship to edentulous partial aras. "nMaterials and Methods: 73 pontics in 57 patients have been included in this cross-sectional study. These patients were under treatment in the department of prosthodontics. A primary cast was achieved from each patient and then the cross-sectional contour of edentulous ridge was depicted. For each patient the type of pontic design was derived from textbook standards and then compared with the design of actual verified Prosthesis at delivery. The shape of tissue surface of each denture was determined by a low viscous impression material. The result of each comparison was recorded in a chart data set. "nResults: The most common pontic design was Modified ridge lap with frequency of 93.2%. The type of ridge was %45.2 normal, %19.2 class I, %8.2 class II and %27.4 class III, respectively. %72.6 of pontics tested have inappropriate design in tissue surface. "nConclusion: It seems that in a high percentage of cases the tissue surface contour of prescribed pontics in department of prosthodontics was incorrect and more attention must be paid to the education of students and technicians.

Crocodile jaw sign

Directory of Open Access Journals (Sweden)

Brij Sharma

2016-01-01

Full Text Available This teaching image highlights the CT abdominal imaging finding of 'crocodile jaw sign' which should raise concern about the presence of an incomplete annular pancreas which causes partial encasement of the duodenum.

Psychometric properties of the WHO-5 Well-being index in partially edentulous patients

Directory of Open Access Journals (Sweden)

Miguel Simancas-Pallares

2016-10-01

Full Text Available Introduction: Measuring well-being in dental patients allows early detection of emotional disorders. Objective: To evaluate the psychometric properties of the Wellbeing index by the World Health Organization (WHO-5 WBI in partially edentulous patients. Materials and methods: Scale validation study and diagnostic tests without reference standard performed in 105 patients treated at an oral implantology service. The WHO-5 WBI was applied before treatment and an exploratory factor analysis was performed to determine the amount of factors in the construct that confirmed its validity and internal consistency through Cronbach’s alpha and McDonald’s omega. Results: The exploratory factor analysis showed a single factor solution that accounted for 56.17% of the variance. The confirmatory analysis showed adjustment indexes X2=1120.516; df=10, p=0.04; RMSEA=0.134 (90% CI: 0.056-0.217; CFI=0.992; TLI=0.983 and WRMR= 0.61. Conclusions: The WHO-5 WBI showed acceptable reproducibility, one-dimensional factor structure and questionable construct validity.

Full mouth rehabilitation with retrievable metal-ceramic implant-supported fixed prostheses for a young patient with atrophic jaws: a clinical report.

Science.gov (United States)

Ameri, Narges; Alikhasi, Marzieh; Rezayani, Vida

2017-09-01

Treatment of atrophic edentulous jaws with implant-supported fixed prostheses is one of the most complicated challenges in dentistry. This clinical report describes the prosthesis which consists of screw retained frameworks with individual cement retained crowns which combines the advantages of the screw retained restoration with the advantage of cement retained.

10-year survival rate and the incidence of peri-implant disease of 374 titanium dental implants with a SLA surface: a prospective cohort study in 177 fully and partially edentulous patients

NARCIS (Netherlands)

van Velzen, F.J.J.; Ofec, R.; Schulten, E.A.J.M.; ten Bruggenkate, C.M.

2015-01-01

Purpose This prospective cohort study evaluates the 10-year survival and incidence of peri-implant disease at implant and patient level of sandblasted, large grid, and acid-etched titanium dental implants (Straumann, soft tissue level, SLA surface) in fully and partially edentulous patients.

[Pain in edentulous patients

NARCIS (Netherlands)

Baat, C. de

2006-01-01

In daily social life, orofacial pain is strongly associated with teeth. However, edentulousness is no lifetime guarantee of being pain-free in the orofacial region. Common oral pains in edentulous people are caused by denture misfits or occlusal errors, by alveolar ridge atrophy, by (sharp)

Clinical evaluation of failures in removable partial dentures.

Science.gov (United States)

Jorge, Janaina H; Quishida, Cristiane C C; Vergani, Carlos E; Machado, Ana L; Pavarina, Ana C; Giampaolo, Eunice T

2012-01-01

The aim of this clinical study was to evaluate the effects of removable partial dentures on the support tissues and changes occurring in lower tooth-supported and bilateral distal-extension dentures, 5 years after placement. The study involved analysis of a total of 53 patients who received prosthetic treatment for removable partial dentures. The patients were divided into two groups. In group 1, the patients had a completely edentulous maxilla and an edentulous area with natural teeth remaining in both the anterior and posterior regions. In group 2, the patients had a completely edentulous maxilla and partially edentulous mandible with preserved anterior teeth. Tooth mobility, prevalence of caries, fracture of the abutment teeth, fracture and/or deformation of the removable partial denture components and stability of the denture base were evaluated. The use of a removable partial denture increased tooth mobility, reduced the prevalence of caries, and did not cause loss or fracture of the abutments or damage to their components, when compared with the baseline. It was concluded that there was no difference between the groups as evaluated in terms of tooth mobility, prevalence of caries, loss and fracture of the abutments or damage to the components of the removable partial denture.

Clinical Evaluation of Small Diameter Straumann Implants in Partially Edentulous Patients: A 5-Year Retrospective Study

Directory of Open Access Journals (Sweden)

S. OZER

2011-06-01

Full Text Available Objective: The aim of the present study was to retrospectively evaluate small-diameter (3.3 mm Straumann® dental implants placed in the maxilla or the mandible over a period of 5 years in function.Materials and Methods: Twenty- eight partially edentulous patients received a total of 48 implants over a 5-year period. After the standard healing period (3 to 6 months, the implants were restored with single-tooth prostheses or fixed partial dentures. All patients were followed according to a strict maintenance program with regular recalls. The cumulative survival rates of implants were analyzed and prosthetic complications were assessed.Results: After 5 years of function, one single 10-mm-long implant in the maxillary premolar region was lost because of recurrent peri-implant infection in a female patient. Two single 10-mm-long maxillary implants placed in the posterior region were lost due to body fracture. The cumulative 5-year survival rate of the implants was 93.75 %. The most common prosthetic complication was loosening of the occlusal screw.Conclusion: Within the limited observation period and the number of patients included in this study, it may be concluded that the use of small-diameter implants appears to be predictable if clinical guidelines are followed and appropriate prosthetic restorations are provided. However, it should be noted that fatigue fracture may occur.

Retrospective cohort clinical investigation of a dental implant with a narrow diameter and short length for the partial rehabilitation of extremely atrophic jaws.

Science.gov (United States)

Maló, Paulo S; de Araújo Nobre, Miguel A; Lopes, Armando V; Ferro, Ana S

2017-01-01

We investigated the short-term clinical outcomes of narrow-diameter short-length implants for the fixed-prosthetic partial rehabilitation of extremely resorbed jaws. Twenty-three patients requiring partial rehabilitations with narrow-platform short-length implants in any jaw were included in this study. In total, 30 implants 3.3 mm in diameter and 7 (n = 15 implants) or 8.5 (n = 15 implants) mm in length were inserted. The primary outcome measure was implant cumulative survival rate (CSR); the secondary outcome measures were marginal bone resorption at 1 and 3 years and the incidence of biologic and mechanical complications. Five patients (21.7%) with six implants (20%) were lost to follow-up. Two implants failed in two patients, yielding a CSR at 3 years of follow-up of 93.4%. The average (standard deviation) marginal bone resorption was 1.34 mm (0.95 mm) after the first year and 1.38 mm (0.78 mm) after the third year. Biologic complications occurred in three patients; mechanical complications occurred in three patients. Despite the limitations of the study, our findings show that the use of new narrow-diameter short-length implants for the rehabilitation of extremely atrophic regions is viable in the short-term, and can be considered a treatment alternative in extremely resorbed jaws.

Telescopic overdenture: Perio-prostho concern for advanced periodontitis

Directory of Open Access Journals (Sweden)

Roma Goswami

2013-01-01

Full Text Available The crown- and sleeve-coping denture is a removable prosthesis that is supported by both selectively retained teeth and the residual ridge or mucosa. It is a versatile and successful means of achieving long-term restoration of a partially edentulous jaw. Insertion and removal of the denture and routine oral hygiene are easy to perform. The beneficial results of this form of treatment can be considered for a wide variety of clinical applications for the severely advanced periodontitis case. This paper presents a case report on the prosthetic rehabilitation of a partially edentulous patient with a telescopic overdenture for the mandible and complete denture for the maxilla.

Clinical Evaluation of Implant-Supported Removable Partial Dentures With a Stress-Breaking Attachment.

Science.gov (United States)

Suzuki, Yasunori; Kono, Kentaro; Shimpo, Hidemasa; Sato, Yohei; Ohkubo, Chikahiro

2017-08-01

The stress-breaking ball (SBB) attachment can distribute the occlusal force equally between the alveolar ridge and the implants. The purpose of this study was to evaluate the implant-supported distal extension removable partial dentures (RPDs) with SBB attachment in 10 patients who were partially edentulous. This randomized crossover study was designed to compare the function of RPDs with and without healing abutments and SBB attachments to support the posterior aspects of the RPDs. Mandibular jaw movements during mastication and the occlusal force and contact area were measured with a commercially available tracking device and pressure-sensitive sheets. Using a visual analog scale, 4 criteria-chewing, retention, stability, and comfort-were evaluated. All of the data obtained were analyzed using a 1-way analysis of variance (α = 0.05). There were no significant differences in either the mean time or the coefficient of variation among the SBB attachments and healing abutments of implant-supported removable partial dentures (ISRPDs) and conventional removable partial dentures (CRPDs). SBB attachments and healing abutments of ISRPDs had greater forces and contact areas than those of CRPDs with significant differences. For all criteria, patients preferred SBB attachments to healing abutments and CRPDs. The implant-supported distal extension RPDs with SBB attachment improved denture stability and patients' satisfaction.

Aesthetics and Survival of Immediately Restored Implants in Partially Edentulous Anterior Maxillary Patients

Directory of Open Access Journals (Sweden)

Roni Kolerman

2018-03-01

Full Text Available This retrospective study was undertaken to determine survival rates and aesthetic outcomes of immediate placement of multiple implants at anterior maxilla sites. One hundred and eighteen implants placed in 39 patients (21 women and 18 men; average age 58.3 years were immediately restored (24–72 h after placement. Aesthetic assessment, radiographic bone loss, and biological and prosthetic complications were evaluated. Data collection between 12 and 84 months (mean 32.2 ± 18 after final prosthetic installation revealed that no implants were lost, and that 106/118 (89.8% implants had no more than 1.5 mm of bone loss by the end of the first year and an additional 0.2 mm for each successive year. The marginal bone loss was higher for extractions due to periodontitis compared to extractions due to caries (mean mesial loss of 1.37 mm vs. 1.01 mm, respectively, and mean distal loss of 1.37 mm and 0.99 mm, respectively, p = 0.001. The mesial papilla was present in 83/118 implants (70.3%, while the distal papilla was present in 76/118 implants (64.4%. The cervical metallic part of the abutment was exposed in 16/118 (13.5% implants. There was a higher ratio of recessions and missing papillae in patients in whom the extractions were performed due to periodontal reasons. Within the limitations of the present study, aesthetic and radiographic parameters support immediate restoration of partially edentulous maxillae.

Edentulism in high poverty rural counties.

Science.gov (United States)

Mitchell, Jordan; Bennett, Kevin; Brock-Martin, Amy

2013-01-01

To examine the differences in oral health status among residents of high-poverty counties, as compared to residents of other rural or urban counties, specifically on the prevalence of edentulism. We used the 2005 Behavioral Risk Factor Surveillance System (BRFSS) and the 2006 Area Resource File (ARF). All analyses were conducted with SAS and SAS-callable SUDAAN, in order to account for weighting and the complex sample design. Characteristics significantly related to edentulism include: geographic location, gender, race, age, health status, employment, insurance, not having a usual source of care, education, marital status, presence of chronic disease, having an English interview, not deferring care due to cost, income, and dentist saturation within the county. Significant associations between high-poverty rural and other rural counties and edentulism were found, and other socioeconomic and health status indicators remain strong predictors of edentulism. © 2012 National Rural Health Association.

The NobelGuide® All-on-4® Treatment Concept for Rehabilitation of Edentulous Jaws: A Retrospective Report on the 7-Years Clinical and 5-Years Radiographic Outcomes.

Science.gov (United States)

Lopes, Armando; Maló, Paulo; de Araújo Nobre, Miguel; Sánchez-Fernández, Elena; Gravito, Inês

2017-04-01

-five patients (22%) registered peri-implant pathology. Within the limitations of this study, it is possible to conclude that this treatment modality for completely edentulous jaws is possible with high long-term survival outcomes. Bruxing and smoking habits had a negative impact on implant failure, mechanical, and biological complications. © 2016 Wiley Periodicals, Inc.

Precision of jaw-closing movements for different jaw gaps.

Science.gov (United States)

Hellmann, Daniel; Becker, Georg; Giannakopoulos, Nikolaos N; Eberhard, Lydia; Fingerhut, Christopher; Rammelsberg, Peter; Schindler, Hans J

2014-02-01

Jaw-closing movements are basic components of physiological motor actions precisely achieving intercuspation without significant interference. The main purpose of this study was to test the hypothesis that, despite an imperfect intercuspal position, the precision of jaw-closing movements fluctuates within the range of physiological closing movements indispensable for meeting intercuspation without significant interference. For 35 healthy subjects, condylar and incisal point positions for fast and slow jaw-closing, interrupted at different jaw gaps by the use of frontal occlusal plateaus, were compared with uninterrupted physiological jaw closing, with identical jaw gaps, using a telemetric system for measuring jaw position. Examiner-guided centric relation served as a clinically relevant reference position. For jaw gaps ≤4 mm, no significant horizontal or vertical displacement differences were observed for the incisal or condylar points among physiological, fast, and slow jaw-closing. However, the jaw positions under these three closing conditions differed significantly from guided centric relation for nearly all experimental jaw gaps. The findings provide evidence of stringent neuromuscular control of jaw-closing movements in the vicinity of intercuspation. These results might be of clinical relevance to occlusal intervention with different objectives. © 2013 Eur J Oral Sci.

Thinking pattern of first grade students towards edentulous replacement

Directory of Open Access Journals (Sweden)

Eri H. Jubhari

2007-06-01

Full Text Available Many people ignore their oral hygiene and do not use denture after extraction. This may caused by their thinking pattern. Thinking pattern indicates the degree of comprehension to solve a problem. This research aims to find out the thinking pattern of first year students towards edentulous replacement. The questionnaire was filled in by students. The oral cavity state of students who have edentulous was inspected. The study finds that only 3 men and 27 women had edentulous, all of them did not use denture. However, more than 96% of the edentulous and not-edentulous groups said that edentulous need denture, due to aesthetic factor. The reasons for not using denture are, for example, not enough time, not disturbed by the absence of denture, and its cost. It can be concluded that the 2005 batch students of Faculty of Dentistry (FKG UNHAS had shown a good understanding about edentulous replacement. Their views on the profits and detriments using denture are the main reasons to determine whether they will use denture.

Removable partial dentures: clinical concepts.

Science.gov (United States)

Bohnenkamp, David M

2014-01-01

This article provides a review of the traditional clinical concepts for the design and fabrication of removable partial dentures (RPDs). Although classic theories and rules for RPD designs have been presented and should be followed, excellent clinical care for partially edentulous patients may also be achieved with computer-aided design/computer-aided manufacturing technology and unique blended designs. These nontraditional RPD designs and fabrication methods provide for improved fit, function, and esthetics by using computer-aided design software, composite resin for contours and morphology of abutment teeth, metal support structures for long edentulous spans and collapsed occlusal vertical dimensions, and flexible, nylon thermoplastic material for metal-supported clasp assemblies. Copyright © 2014 Elsevier Inc. All rights reserved.

Corrective Jaw Surgery

Medline Plus

Full Text Available ... out more. Corrective Jaw Surgery Corrective Jaw Surgery Orthognathic surgery is performed to correct the misalignment of jaws ... out more. Corrective Jaw Surgery Corrective Jaw Surgery Orthognathic surgery is performed to correct the misalignment of jaws ...

Asymptomatic radiopaque lesions of the jaws. A radiographic study using cone-beam computed tomography

International Nuclear Information System (INIS)

Araki, Masao; Matsumoto, Naoyuki; Matsumoto, Kunihito; Ohnishi, Masaaki; Honda, Kazuya; Komiyama, Kazuo

2011-01-01

Panoramic radiography and cone-beam computed tomography (CT) were used to analyze asymptomatic radiopaque lesions in the jaw bones and determine the diagnostic relevance of the lesions based on their relationships to teeth and site of origin. One hundred radiopaque lesions detected between 1998 and 2002 were examined by both panoramic radiography and cone-beam CT. On the basis of panoramic radiographs, the region was classified as periapical, body, or edentulous, and the site was classified as molar or premolar. Follow-up data from medical records were available for only 36 of these cases. The study protocol for simultaneous use of cone-beam CT was approved by the ethics review board of our institution. A large majority of radiopaque lesions were observed in premolar and molar sites of the mandible; 60% of lesions were periapical, 24% were in the body, and 16% were in the edentulous region. An interesting type of radiopaque lesion, which we named a pearl shell structure (PSS), was observed on cone-beam CT in 34 of the 100 lesions. The PSS is a distinctive structure, and this finding on cone-beam CT likely represents the start of bone formation before bone sclerosis. (author)

[Acrylic resin removable partial dentures

NARCIS (Netherlands)

Baat, C. de; Witter, D.J.; Creugers, N.H.J.

2011-01-01

An acrylic resin removable partial denture is distinguished from other types of removable partial dentures by an all-acrylic resin base which is, in principle, solely supported by the edentulous regions of the tooth arch and in the maxilla also by the hard palate. When compared to the other types of

Open-mouth jaw locking in cats: a literature review and use of computed tomography in three cases.

Science.gov (United States)

Nutt, Anna E; Anderson, Thomas; Gracis, Margherita; Doran, Ivan; Warren-Smith, Chris; Langley-Hobbs, Sorrel J

2017-11-01

Case series summary This report summarises and reviews the published cases of open-mouth jaw locking in cats and describes three further cases. Case 1 was a 5-year-old, 5.3 kg male neutered domestic shorthair cat. CT identified changes consistent with temporomandibular joint (TMJ) dysplasia with osseous degenerative changes, and the cat subsequently underwent bilateral partial zygomectomy with bilateral partial coronoidectomy. Case 2 was a 10-year-old, 6.0 kg male neutered Exotic Shorthair. Aside from a fracture of the left maxillary canine tooth crown and absence of the left maxillary fourth premolar tooth, no abnormalities were found on CT scan. The cat also underwent bilateral partial zygomectomy with bilateral partial coronoidectomy. The third case was a 1-year-old, 4.0 kg male neutered Persian cat. Changes on CT were consistent with bilateral TMJ dysplasia, and the cat underwent staged bilateral partial zygomectomy with bilateral partial coronoidectomy. There was no recurrence of open-mouth jaw locking in any of the cases on long-term follow-up. Relevance and novel information Open-mouth jaw locking has been reported in cats of a wide range of ages, from 1-10 years of age. Cats with all skull types (brachycephalic, mesaticephalic and dolichocephalic) may be affected, but brachycephalic breeds seem to be over-represented. A CT scan with the jaw locked in place is recommended for diagnosis and surgical planning purposes; two of the cases reported here document the first cases of TMJ dysplasia in cats to be definitively diagnosed using CT. Trauma and symphyseal or TMJ laxity may also predispose to development of the condition. Partial coronoidectomy and partial zygomatic arch resection performed alone or in combination are generally successful at preventing recurrence. Bilateral partial zygomectomy with bilateral partial coronoidectomy has not previously been reported as a surgical treatment, and is recommended when open-mouth jaw locking occurs bilaterally.

A radiographic study on the prevalence of knife-edge residual alveolar ridge at proposed dental implant sites

International Nuclear Information System (INIS)

AlFaleh, Wafaa

2009-01-01

Dental implants are widely used in restoration of completely or partially edentulous dental arches. Before placement of endosseous implants in the jaws, both the quantity and quality of the residual ridge must be assessed radiographically. Remodeling activity after tooth extraction is localized primarily at the crestal area of the residual ridges, resulting in reduction of the height of bone and creation of various three-dimensional shapes of the residual ridges. When bone resorption at the lingual and buccal aspects is greater than that at the crestal area, a knife-edge type of residual ridge develops. The aim of this study was to evaluate the prevalence of the knife-edge morphology of the residual alveolar bone at proposed implant sites in partially or completely edentulous patients. Computed tomography (CT) cross-sectional images of the upper and lower jaws were assessed at the proposed sites before implant placement. Images of 258 proposed implant sites belonging to 30 patients were assessed radiographically. In 120 proposed implant sites out of 258 (46.5%), the residual alveolar ridge had a knife-edge configuration, the majority belonging to completely edentulous patients who lost their teeth more than ten years previously. High prevalence of knife-edge ridge was found, therefore, replacement of missing teeth by immediate implant is recommended to prevent atrophy or knife-edge morphology of the residual ridge. (author)

Influence of mastication and edentulism on mandibular bone density.

Science.gov (United States)

Chou, Hsuan-Yu; Satpute, Devesh; Müftü, Ali; Mukundan, Srinivasan; Müftü, Sinan

2015-01-01

The aim of this study was to demonstrate that external loading due to daily activities, including mastication, speech and involuntary open-close cycles of the jaw contributes to the internal architecture of the mandible. A bone remodelling algorithm that regulates the bone density as a function of stress and loading cycles is incorporated into finite element analysis. A three-dimensional computational model is constructed on the basis of computerised tomography (CT) images of a human mandible. Masticatory muscle activation involved during clenching is modelled by static analysis using linear optimisation. Other loading conditions are approximated by imposing mandibular flexure. The simulations predict that mandibular bone density distribution results in a tubular structure similar to what is observed in the CT images. Such bone architecture is known to provide the bone optimum strength to resist bending and torsion during mastication while reducing the bone mass. The remodelling algorithm is used to simulate the influence of edentulism on mandibular bone loss. It is shown that depending on the location and number of missing teeth, up to one-third of the mandibular bone mass can be lost due to lack of adequate mechanical stimulation.

Jaw Dislocation

Science.gov (United States)

... the lower jaw. They press down on the back teeth and push the chin up until the jaw joints return to their normal location. Once the jaw is back in place, doctors sometimes apply a Barton bandage ( ...

[Functional load distribution in cases of different types of removable dentures fastening].

Science.gov (United States)

Zhulev, E N; Klokov, A A

2007-01-01

Questions of studying of a biomechanics of system prosthesis - prosthetic region using of mathematical modelling are surveyed. The original way of definition of physical parameters of a mucosa of an edentulous alveolar process is offered. Modelling of a leaky adhering of prosthesis basis to a mucosa as free saddle situation shows, that a abutment teeth and an edentulous alveolar part of a jaw are in an optimum situation at sliding resilient fastening of a removable partial denture. Rigid bond in the given situation on the contrary promotes development of an overload of abutment teeth and their inclination distally.

Jaw1/LRMP has a role in maintaining nuclear shape via interaction with SUN proteins.

Science.gov (United States)

Kozono, Takuma; Tadahira, Kazuko; Okumura, Wataru; Itai, Nao; Tamura-Nakano, Miwa; Dohi, Taeko; Tonozuka, Takashi; Nishikawa, Atsushi

2018-06-06

Jaw1/LRMP is characterized as a type II integral membrane protein that is localized to endoplasmic reticulum (ER), however, its physiological functions have been poorly understood. An alignment of amino acid sequence of Jaw1 with KASH proteins, outer nuclear membrane proteins, revealed that Jaw1 has a partial homology to the KASH domain. Here, we show that the function of Jaw1 is to maintain nuclear shape in mouse melanoma cell line. The siRNA-mediated knockdown of Jaw1 caused a severe defect in nuclear shape, and the defect was rescued by ectopic expression of siRNA-resistant Jaw1. Since co-immunoprecipitation assay indicates that Jaw1 interacts with SUN proteins that are inner nuclear proteins and microtubules, this study suggests that Jaw1 has a role in maintaining nuclear shape via interactions with SUN proteins and microtubules.

Implications of Edentulism on Quality of Life among Elderly

Directory of Open Access Journals (Sweden)

Efigênia Ferreira e Ferreira

2012-01-01

Full Text Available This study aimed was to test the association between quality of life and edentulism among elderly individuals in a city in southeastern Brazil. This cross-sectional study was carried out with 163 individuals aged 60 years or older, functionally independent and non-institutionalized. Data were collected with a questionnaire and oral examination. The edentulism was the dependent variable. The independent variables were sex, age, household income and quality of life (WHOQOL-Old and their scores. To assess the association between the dependent variable and independent variables was used bivariate analysis (p < 0.10. Poisson regression model was performed, adjusting for age and sex. The average age of participants was 69 years (± 6.1, 68.7% were female and 52.8% were diagnosed as completely edentulous (90% CI: 0.33–1.24. When the independent variables were associated to the prevalence of edentulism, statistically significant associations were found for age (p = 0.03 and social participation dimension of the WHOQOL-Old (p = 0.08. In the Poisson regression, social participation remained statistically associated to edentulism {RP = 2.12 [90% CI (1.10–4.00]}. The social participation proved to have a significant association to edentulism, thereby attesting to the negative effect of this condition on social aspects.

Lack of dental insurance is correlated with edentulism.

Science.gov (United States)

Simon, Lisa; Nalliah, Romesh P; Seymour, Brittany

2015-01-01

The correlation between insurance status and edentulism has not previously been reported in a population with known access to a dentist, and little is known about patient demographics in corporate dental settings. This study investigated patient demographics of a former dental franchise in Chicopee, Massachusetts, and examined a correlation between dental insurance and edentulism in this group. The correlation of edentulism with age, gender, and dental risk factors (diabetes, temporomandibular disorder, trouble with previous dental work, or oral sores and ulcers) was also examined. This was a retrospective case study. Age, gender, and presence of dental risk factors were recorded from the patient medical history intake form. Dentate status was recorded from patient odontograms. Dental insurance status was obtained from billing records. Data was aggregated and deidentified. Descriptive and bivariate statistics and logistic regression models were used to identify associations (p-value ≤ 0.05 significance). Of 1,123 records meeting inclusion criteria, 52.54 percent of patients had dental insurance, 26.27 percent had at least one dental risk factor, and 18.17 percent were edentulous. Age and insurance status were significantly correlated with edentulism. Correcting for age, individuals without insurance were 1.56 times as likely to be edentulous. This case study provides insight into patient demographics that might seek care in a corporate setting and suggests that access to a dentist alone may not be adequate in preserving the adult dentition; dental insurance may also be important to health. As the corporate dental practice model continues to grow, these topics deserve further study.

Removable partial overdentures for the irradiated patient

International Nuclear Information System (INIS)

Rosenberg, S.W.

1990-01-01

Patients who have received radiotherapy to the head and neck area must avoid dental extractions and seek simplicity in treatment and home care follow-up. For partially edentulous patients, removable partial overdenture therapy can fulfill these goals while maintaining the high level of function and aesthetics desired by patients.11 references

Treatment of Orally Handicapped Edentulous Older Adults Using Dental Implants.

Science.gov (United States)

Zahedi, Charles

2016-07-01

The oral handicap of complete edentulism is the terminal outcome of a multifactorial process involving biological factors and patient-related factors. Fully edentulous orally handicapped older adults have been neglected because removable acrylic dentures have been the classic therapy for complete edentulism but are only rehabilitative, not therapeutic. Not replacing missing teeth with stable dentures could prevent adequate food intake. Osseointegrated endosseous implants used as a therapeutic adjunct can reduce the problem of long-term bone resorption to less than 0.1 mm per year. Implant-borne prostheses substantially increase the overall health and quality of life of orally handicapped fully edentulous older adults. Copyright © 2016 Elsevier Inc. All rights reserved.

Removable partial dentures: The clinical need for innovation.

Science.gov (United States)

Campbell, Stephen D; Cooper, Lyndon; Craddock, Helen; Hyde, T Paul; Nattress, Brian; Pavitt, Sue H; Seymour, David W

2017-09-01

The number of partially dentate adults is increasing, and many patients will require replacement of missing teeth. Although current treatment options also include fixed partial dentures and implants, removable partial dentures (RPDs) can have advantages and are widely used in clinical practice. However, a significant need exists to advance materials and fabrication technologies because of the unwanted health consequences associated with current RPDs. The purpose of this review was to assess the current state of and future need for prosthetics such as RPDs for patients with partial edentulism, highlight areas of weakness, and outline possible solutions to issues that affect patient satisfaction and the use of RPDs. The data on treatment for partial edentulism were reviewed and summarized with a focus on currently available and future RPD designs, materials, means of production, and impact on oral health. Data on patient satisfaction and compliance with RPD treatment were also reviewed to assess patient-centered care. Design, materials, ease of repair, patient education, and follow-up for RPD treatment all had a significant impact on treatment success. Almost 40% of patients no longer use their RPD within 5 years because of factors such as sociodemographics, pain, and esthetics. Research on RPD-based treatment for partial edentulism for both disease-oriented and patient-centered outcomes is lacking. Future trials should evaluate new RPD materials and design technologies and include both long-term follow-up and health-related and patient-reported outcomes. Advances in materials and digital design/production along with patient education promise to further the application of RPDs and improve the quality of life for patients requiring RPDs. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Corrective Jaw Surgery

Medline Plus

Full Text Available ... misalignment of jaws and teeth. Surgery can improve chewing, speaking and breathing. While the patient's appearance may ... indicate the need for corrective jaw surgery: Difficulty chewing, or biting food Difficulty swallowing Chronic jaw or ...

Flexible Thermoplastic Denture Base Materials for Aesthetical Removable Partial Denture Framework

OpenAIRE

Singh, Kunwarjeet; Aeran, Himanshu; Kumar, Narender; Gupta, Nidhi

2013-01-01

Conventional fixed partial dentures, implant supported Fixed Partial Dentures (FDPs) and removable partial dentures are the most common treatment modalities for the aesthetic and functional rehabilitation of partially edentulous patients. Although implants and FDP have certain advantages over removable partial dentures, in some cases, removable partial dentures may be the only choice which is available. Removable cast partial dentures are used as definitive removable prostheses when indicated...

Interdisciplinary treatment for a compensated Class II partially edentulous malocclusion: Orthodontic creation of a posterior implant site.

Science.gov (United States)

Chiu, Grace; Chang, Chris; Roberts, W Eugene

2018-03-01

A 36-year-old woman with good periodontal health sought treatment for a compensated Class II partially edentulous malocclusion associated with a steep mandibular plane (SN-MP, 45°), 9 missing teeth, a 3-mm midline discrepancy, and compromised posterior occlusal function. She had multiple carious lesions, a failing fixed prostheses in the mandibular right quadrant replacing the right first molar, and a severely atrophic edentulous ridge in the area around the mandibular left first and second molars. After restoration of the caries, the mandibular left third molar served as anchorage to correct the mandibular arch crowding. The mandibular left second premolar was retracted with a light force of 2 oz (about 28.3 cN) on the buccal and lingual surfaces to create an implant site between the premolars. Modest lateral root resorption was noted on the distal surface of the mandibular left second premolar after about 7 mm of distal translation in 7 months. Six months later, implants were placed in the mandibular left and right quadrants; the spaces were retained with the fixed appliance for 5 months and a removable retainer for 1 month. Poor cooperation resulted in relapse of the mandibular left second premolar back into the implant site, and it was necessary to reopen the space. When the mandibular left fixture was uncovered, a 3-mm deep osseous defect on the distobuccal surface was found; it was an area of relatively immature bundle bone, because the distal aspect of the space was reopened after the relapse. Subsequent bone grafting resulted in good osseous support of the implant-supported prosthesis. The relatively thin band of attached gingiva on the implant at the mandibular right first molar healed with a recessed contour that was susceptible to food impaction. A free gingival graft restored soft tissue form and function. This severe malocclusion with a discrepancy index value of 28 was treated to an excellent outcome in 38 months of interdisciplinary treatment

Morphology and evolution of the jaw suspension in lamniform sharks.

Science.gov (United States)

Wilga, C D

2005-07-01

The morphology of the jaw suspension and jaw protrusion mechanism in lamniform sharks is described and mapped onto a cladogram to investigate how changes in jaw suspension and protrusion have evolved. This has revealed that several evolutionary modifications in the musculoskeletal apparatus of the jaws have taken place among lamniform sharks. Galeomorph sharks (Carcharhiniformes, Lamniformes, Orectolobiformes, and Heterodontiformes) have paired ethmopalatine ligaments connecting the ethmoid process of the upper jaw to the ethmoid region of the cranium. Basal lamniform sharks also acquired a novel single palatonasal ligament connecting the symphysis of the upper jaw to the cranium mid-ventral to the nasal capsule. Sharks in the family Lamnidae subsequently lost the original paired ethmopalatine ligament while retaining the novel palatonasal ligament. Thus, basal lamniform taxa (Mitsukurina owstoni, Carcharius taurus, Alopias vulpinnis) have increased ligamentous support of the lateral region of the upper jaw while derived species (Lamnidae) have lost this lateral support but gained anterior support. In previous studies the morphology of the jaw suspension has been shown to play a major role in the mechanism of upper jaw protrusion in elasmobranchs. The preorbitalis is the primary muscle effecting upper jaw protrusion in squalean (sister group to galeomorphs) and carcharhiniform (sister group to lamniforms) sharks. The preorbitalis originates from the quadratomandibularis muscle and inserts onto the nasal capsule in squalean and carcharhiniform sharks. Carcharhiniform sharks have evolved a subdivided preorbitalis muscle with the new division inserting near the ethmoid process of the palatoquadrate (upper jaw). Alopid sharks have also independently evolved a partially subdivided preorbitalis with the new division inserting at the base of the ethmoid process and surrounding connective tissue. Lamnid sharks have retained the two preorbitalis divisions but have modified

SU-F-T-531: Determination of Site-Specific Dynamic-Jaw Versus Static-Jaw RapidArc Delivery

Energy Technology Data Exchange (ETDEWEB)

Tien, C [Community Hospital, Munster, IN (United States); Brewer, M [Franciscan St Margaret Health, Hammond, IN (United States); Studenski, M [University of Miami, Miami, FL (United States)

2016-06-15

Purpose: Dynamic-jaw tracking maximizes the area blocked by both jaw and MLC in RapidArc. We developed a method to quantify jaw tracking. Methods: An Eclipse Scripting API (ESAPI) was used to export beam parameters for each arc’s control points. The specific beam parameters extracted were: gantry angle, control point number, meterset, x-jaw positions, y-jaw positions, MLC bank-number, MLC leaf-number, and MLC leaf-position. Each arc contained 178 control points with 120 MLC positions. MATLAB routines were written to process these parameters in order to calculate both the beam aperture (unblocked) size for each control point. An average aperture size was weighted by meterset. Jaw factor was defined as the ratio between dynamic-jaw to static-jaw aperture size. Jaw factor was determined for forty retrospectively replanned patients treated with static-jaw delivery sites including lung, brain, prostate, H&N, rectum, and bladder. Results: Most patients had multiple arcs and reduced-field boosts, resulting in 151 fields. Of these, the lowest (0.4722) and highest (0.9622) jaw factor was observed in prostate and rectal cases, respectively. The median jaw factor was 0.7917 meaning there is the potential unincreased blocking by 20%. Clinically, the dynamic-jaw tracking represents an area surrounding the target which would receive MLC-only leakage transmission of 1.68% versus 0.1% with jaws. Jaw-tracking was more pronounced at areas farther from the target. In prostate patients, the rectum and bladder had 5.5% and 6.3% lower mean dose, respectively; the structures closer to the prostate such as the rectum and bladder both had 1.4% lower mean dose. Conclusion: A custom ESAPI script was coupled with a MATLAB routine in order to extract beam parameters from static-jaw plans and their replanned dynamic-jaw deliveries. The effects were quantified using jaw factor which is the ratio between the meterset weighted aperture size for dynamic-jaw fields versus static-jaw fields.

Oral cavity and jaw

International Nuclear Information System (INIS)

Solntsev, A.M.; Koval', G.Yu.

1984-01-01

Radioanatome of oral cavity and jaw is described. Diseases of the teeth, jaw, large salivary glands, temporo-mandibular articulation are considered. Roentgenograms of oral cacity and jaw of healthy people are presented and analyzed as well as roentgenograms in the above-mentioned diseases

Nasal mask ventilation is better than face mask ventilation in edentulous patients

OpenAIRE

Kapoor, Mukul Chandra; Rana, Sandeep; Singh, Arvind Kumar; Vishal, Vindhya; Sikdar, Indranil

2016-01-01

Background and Aims: Face mask ventilation of the edentulous patient is often difficult as ineffective seating of the standard mask to the face prevents attainment of an adequate air seal. The efficacy of nasal ventilation in edentulous patients has been cited in case reports but has never been investigated. Material and Methods: Consecutive edentulous adult patients scheduled for surgery under general anesthesia with endotracheal intubation, during a 17-month period, were prospectively ev...

Immediate versus early non-occlusal loading of dental implants placed flapless in partially edentulous patients: a 3-year randomized clinical trial.

Science.gov (United States)

Merli, Mauro; Moscatelli, Marco; Mariotti, Giorgia; Piemontese, Matteo; Nieri, Michele

2012-02-01

To compare immediate versus early non-occlusal loading of dental implants placed flapless in a 3-year, parallel group, randomized clinical trial. The study was conducted in a private dental clinic between July 2005 and July 2010. Patients 18 years or older were randomized to receive implants for fixed partial dentures in cases of partial edentulism. The test group was represented by immediate non-occlusal implant loading, whereas the control group was represented by early non-occlusal implant loading. The outcome variables were implant failure, complications and radiographic bone level at implant sites 3 years after loading, measured from the implant-abutment junction to the most coronal point of bone-to-implant contact. Randomization was computer-generated with allocation concealment by opaque sequentially numbered sealed envelopes, and the measurer was blinded to group assignment. Sixty patients were randomized: 30 to the immediately loaded group and 30 to the early loaded group. Four patients dropped out; however, the data of all patients were included in the analysis. No implant failure occurred. Two complications occurred in the control group and one in the test group. The mean bone level at 3 years was 1.91 mm for test group and 1.59 mm for control group. The adjusted difference in bone level was 0.26 mm (CI 95% -0.08 to 0.59, p = 0.1232). The null hypothesis of no difference in failure rates, complications and bone level between implants that were loaded immediately or early at 3 years cannot be rejected in this randomized clinical trial. © 2011 John Wiley & Sons A/S.

Functional Morphology of Eunicidan (Polychaeta) Jaws

Science.gov (United States)

Clemo, W. C.; Dorgan, K. M.

2016-02-01

Polychaetes exhibit diverse feeding strategies and diets, with some species possessing hardened teeth or jaws of varying complexity. Species in the order Eunicida have complex, rigidly articulated jaws consisting of multiple pairs of maxillae and a pair of mandibles. While all Eunicida possess this general jaw structure, a number of characteristics of the jaw parts vary considerably among families. These differences, described for fossilized and extant species' jaws, were used to infer evolutionary relationships, but current phylogeny shows that jaw structures that are similar among several families are convergent. Little has been done, however, to relate jaw functional morphology and feeding behavior to diet. To explore these relationships, we compared the jaw kinematics of two taxa with similar but evolutionarily convergent jaw structures: Diopatra (Onuphidae) and Lumbrineris (Lumbrineridae). Diopatra species are tube-dwelling and predominantly herbivorous, whereas Lumbrineris species are burrowing carnivores. Jaw kinematics were observed and analyzed by filming individuals biting or feeding and tracking tooth movements in videos. Differences in jaw structure and kinematics between Diopatra and Lumbrineris can be interpreted to be consistent with their differences in diet. Relating jaw morphology to diet would provide insight into early annelid communities by linking fossil teeth (scolecodonts) to the ecological roles of extant species with similar morphologies.

10-year survival rate and the incidence of peri-implant disease of 374 titanium dental implants with a SLA surface: a prospective cohort study in 177 fully and partially edentulous patients.

Science.gov (United States)

van Velzen, Frank J J; Ofec, Ronen; Schulten, Engelbert A J M; Ten Bruggenkate, Christiaan M

2015-10-01

This prospective cohort study evaluates the 10-year survival and incidence of peri-implant disease at implant and patient level of sandblasted, large grid, and acid-etched titanium dental implants (Straumann, soft tissue level, SLA surface) in fully and partially edentulous patients. Patients who had dental implant surgery in the period between November 1997 and June 2001, with a follow-up of at least 10 years, were investigated for clinical and radiological examination. Among the 506 inserted dental implants in 250 patients, 10-year data regarding the outcome of implants were available for 374 dental implants in 177 patients. In the current study, peri-implantitis was defined as advanced bone loss (≧1.5 mm. postloading) in combination with bleeding on probing. At 10-year follow-up, only one implant was lost (0.3%) 2 months after implant surgery due to insufficient osseointegration. The average bone loss at 10 year postloading was 0.52 mm. Advanced bone loss at 10-year follow-up was present in 35 dental implants (9.8%). Seven percent of the observed dental implants showed bleeding on probing in combination with advanced bone loss and 4.2% when setting the threshold for advanced bone loss at 2.0 mm. Advanced bone loss without bleeding on probing was present in 2.8% of all implants. In this prospective study, the 10-year survival rate at implant and patient level was 99.7% and 99.4%, respectively. Peri-implantitis was present in 7% of the observed dental implants according to the above-mentioned definition of peri-implantitis. This study shows that SLA implants offer predictable long-term results as support in the treatment of fully and partially edentulous patients. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Corrective Jaw Surgery

Medline Plus

Full Text Available ... surgery: Difficulty chewing, or biting food Difficulty swallowing Chronic jaw or jaw joint (TMJ) pain and headache ... Inability to make the lips meet without straining Chronic mouth breathing Sleep apnea (breathing problems when sleeping, ...

Corrective Jaw Surgery

Medline Plus

Full Text Available ... and lower jaws and the orbits surrounding the eyes, and facial lacerations. Click here to find out ... and lower jaws and the orbits surrounding the eyes, and facial lacerations. Click here to find out ...

Corrective Jaw Surgery

Medline Plus

Full Text Available ... and Craniofacial Surgery Cleft Lip/Palate and Craniofacial Surgery A cleft lip may require one or more ... find out more. Corrective Jaw Surgery Corrective Jaw Surgery Orthognathic surgery is performed to correct the misalignment ...

Corrective Jaw Surgery

Medline Plus

Full Text Available ... Jaw Surgery Download Download the ebook for further information Corrective jaw, or orthognathic surgery is performed by ... your treatment. Correction of Common Dentofacial Deformities ​ ​ The information provided here is not intended as a substitute ...

A modified occlusal wafer for managing partially dentate orthognathic patients--a case series.

Science.gov (United States)

Soneji, Bhavin Kiritkumar; Esmail, Zaid; Sharma, Pratik

2015-03-01

A multidisciplinary approach is essential in orthognathic surgery to achieve stable and successful outcomes. The model surgery planning is an important aspect in achieving the desired aims. An occlusal wafer used at the time of surgery aids the surgeon during correct placement of the jaws. When dealing with partially dentate patients, the design of the occlusal wafer requires modification to appropriately position the jaw. Two cases with partially dentate jaws are presented in which the occlusal wafer has been modified to provide stability at the time of surgery.

Keratocysts in the jaws

International Nuclear Information System (INIS)

Lipovec, A.; Ihan Hren, N.

2004-01-01

Background. Jaw cysts are a common pathology; among them, the odontogenic keratocysts (OKC) represent a special group because of their aggressive growth and recurrence. Patients and methods. We established retrospectively the epidemiology and clinical characteristics of OKC among all the pathohistologically confirmed jaw cysts that had been surgically cured in the past ten years (from 1994 to 2003) at the Clinical Department of Maxillofacial and Oral Surgery, University Medical Centre in Ljubljana. Results. Among 992 surgically removed jaw cysts, 106 were OKC (10.6% of all). Pathohistological diagnosis of OKC was confirmed in 90 patients, in 51 men (56.7%) and 39 women (43.4%). Mean age of patients with OKC at the time of treatment was 36 years. The youngest one was 7 years old, the oldest one 83 years. Seventy-four (69.8%) of OKC were removed from the lower jaws, 32 (30.2%) from the upper jaws. As to the location, OKC (49 cases - 46.2%) predominated in the angles and vertical branches of the lower jaw. Recurrence rate after the first removal of OKC was 22.2% (in 20 patients). First recurrence occurs most frequently (in 70%) within the first 5 years after primary treatment; the mean time till the first recurrence was 4 years and 7 months. Multiple recurrences of OKC were observed in 9 patients (10% of all patients with OKC). Five of the patients with OKC had the syndrome of basal cell carcinoma (Gorlin-Goltz Sy.). We found out that one third of OKC were clinically unexpected in regard to their untypical locations in the jaws. Conclusions. It is critical for the jaw cysts to be pathohistologically examined. The number of cases of OKC among all jaw cysts in our study is significantly larger (3.5-time) than in the previous epidemiological study in Slovenia; but this may be the consequence of previous underdiagnosis of that pathology entity. Our study is comparative with other similar foreign studies in literature in respect to the patient's sample and epidemiological

Corrective Jaw Surgery

Medline Plus

Full Text Available ... their surgery, orthognathic surgery is performed to correct functional problems. Jaw Surgery can have a dramatic effect on many aspects of life. Following are some of the conditions that may ... front, or side Facial injury Birth defects Receding lower jaw and ...

Evaluation of 4 mm implants in mandibular edentulous patients with reduced bone height. Surgical preliminary results

Directory of Open Access Journals (Sweden)

J.L. Calvo-Guirado

2014-06-01

Full Text Available Aim: Growing evidence has suggested the utility of short dental implants for oral reconstructive procedures in clinical situations of limited vertical bone height. The aim of this short comunication was to evaluate the clinical use of implants < 10 mm in length and to determine short implant-supported prosthesis success in the atrophic jaw. Materials and methods: Six women and three men were recruited for the treatment of edentulous mandibles. A total of 6 implants were inserted in each patient: two anterior implants of conventional lenght and four posterior 4 mm Titanium Zirconium (TiZr implants. The insertion torque and bone denisty were evaluated. Results: The mean insertion torque for the 4 mm implants was lower than for conventional ones, without any statistical difference. Moreover, most of the patients (88% showed a D2 bone type. Conclusion: The provision of short implant-supported prostheses in patients with atrophic alveolar ridges appears to be a successful treatment option in the short term; however, more scientific evidence is needed for the long term.

From Guided Surgery to Final Prosthesis with a Fully Digital Procedure: A Prospective Clinical Study on 15 Partially Edentulous Patients

Directory of Open Access Journals (Sweden)

Giorgio Andrea Dolcini

2016-01-01

Full Text Available Scope. To demonstrate guided implant placement and the application of fixed, implant-supported prosthetic restorations with a fully digital workflow. Methods. Over a 2-year period, all patients with partial edentulism of the posterior maxilla, in need of fixed implant-supported prostheses, were considered for inclusion in this study. The protocol required intraoral scanning and cone beam computed tomography (CBCT, the superimposition of dental-gingival information on bone anatomy, surgical planning, 3D-printed teeth-supported surgical templates, and modelling and milling of polymethylmethacrylate (PMMA temporaries for immediate loading. After 3 months, final optical impression was taken and milled zirconia frameworks and 3D-printed models were fabricated. The frameworks were veneered with ceramic and delivered to the patients. Results. Fifteen patients were selected for this study. The surgical templates were stable. Thirty implants were placed (BTK Safe®, BTK, Vicenza, Italy and immediately loaded with PMMA temporaries. After 3 months, the temporaries were replaced by the final restorations in zirconia-ceramic, fabricated with a fully digital process. At 6 months, none of the patients reported any biological or functional problems with the implant-supported prostheses. Conclusions. The present procedure for fully digital planning of implants and short-span fixed implant-supported restorations has been shown to be reliable. Further studies are needed to validate these results.

Cost-effectiveness of implant-supported mandibular removable partial dentures

NARCIS (Netherlands)

Jensen, Charlotte; Ross, Jamila; Feenstra, Talitha L; Raghoebar, Gerry M; Speksnijder, Caroline; Meijer, Henny J A; Cune, Marco S

ObjectivesThe aim of this study was to conduct a cost-effectiveness analysis comparing conventional removable partial dentures (RPDs) and implant-supported RPDs (ISRPDs) treatment in patients with an edentulous maxilla and a bilateral free-ending situation in the mandible. Material and methodsThirty

Effects of Edentulism on Mandibular Morphology: Evaluation of Panoramic Radiographs

Directory of Open Access Journals (Sweden)

Rıdvan Okşayan

2014-01-01

Full Text Available Purpose. The objective of this study was to evaluate morphological changes of the mandible in edentulous and dentate subjects using panoramic radiographs. Materials and Methods. Panoramic radiographs were divided into the following three groups: Group I (completely edentulous group, Group II (old dentate group and Group III (young dentate group. The research parameters of gonial angle, condylar height, ramus height, ramus notch depth, and antegonial notch depth were measured on panoramic radiographs. The Kruskal-Wallis statistical test was used to determine significant differences in mandibular morphological parameters among the three groups. The Mann-Whitney U test was used to compare the subgroups. Results. Significant differences were found only in ramus height between three groups. According to the Mann-Whitney U test, a significant difference was exhibited among Groups I and II in the ramus height parameter. No significant differences were found in the gonial angle, condylar height, ramus notch depth, or antegonial notch depth when comparing the young dentate, old dentate, and completely edentulous subjects. Conclusions. Significant differences were found only in ramus height between the groups. Ramus height may be an indicator that changed by years and tooth loss. It must be considered that ramus height can be decreased in edentulism.

Retrospective analysis of 56 edentulous dental arches restored with 344 single-stage implants using an immediate loading fixed provisional protocol: statistical predictors of implant failure.

Science.gov (United States)

Kinsel, Richard P; Liss, Mindy

2007-01-01

The purpose of this retrospective study was to evaluate the effects of implant dimensions, surface treatment, location in the dental arch, numbers of supporting implant abutments, surgical technique, and generally recognized risk factors on the survival of a series of single-stage Straumann dental implants placed into edentulous arches using an immediate loading protocol. Each patient received between 4 and 18 implants in one or both dental arches. Periapical radiographs were obtained over a 2- to 10-year follow-up period to evaluate crestal bone loss following insertion of the definitive metal-ceramic fixed prostheses. Univariate tests for failure rates as a function of age ( or = 60 years), gender, smoking, bone grafting, dental arch, surface type, anterior versus posterior, number of implants per arch, and surgical technique were made using Fisher exact tests. The Cochran-Armitage test for trend was used to evaluate the presence of a linear trend in failure rates regarding implant length and implant diameter. Logistic regression modeling was used to determine which, if any, of the aforementioned factors would predict patient and implant failure. A significance criterion of P = .05 was utilized. Data were collected for 344 single-stage implants placed into 56 edentulous arches (39 maxillae and 17 mandibles) of 43 patients and immediately loaded with a 1-piece provisional fixed prosthesis. A total of 16 implants failed to successfully integrate, for a survival rate of 95.3%. Increased rates of failure were associated with reduced implant length, placement in the posterior region of the jaw, increased implant diameter, and surface treatment. Implant length emerged as the sole significant predictor of implant failure. In this retrospective analysis of 56 consecutively treated edentulous arches with multiple single-stage dental implants loaded immediately, reduced implant length was the sole significant predictor of failure.

Edentulism, beaks, and biomechanical innovations in the evolution of theropod dinosaurs.

Science.gov (United States)

Lautenschlager, Stephan; Witmer, Lawrence M; Altangerel, Perle; Rayfield, Emily J

2013-12-17

Maniraptoriformes, the speciose group of derived theropod dinosaurs that ultimately gave rise to modern birds, display a diverse and remarkable suite of skeletal adaptations. Apart from the evolution of flight, a large-scale change in dietary behavior appears to have been one of the main triggers for specializations in the bauplan of these derived theropods. Among the different skeletal specializations, partial or even complete edentulism and the development of keratinous beaks form a recurring and persistent trend in from the evolution of derived nonavian dinosaurs. Therizinosauria is an enigmatic maniraptoriform clade, whose members display these and other osteological characters thought to be correlated with the shift from carnivory to herbivory. This makes therizinosaurians prime candidates to assess the functional significance of these morphological characters. Based on a highly detailed biomechanical model of Erlikosaurus andrewsi, a therizinosaurid from the Upper Cretaceous of Mongolia, different morphological configurations incorporating soft-tissue structures, such as a keratinous rhamphotheca, are evaluated for their biomechanical performance. Our results indicate that the development of beaks and the presence of a keratinous rhamphotheca would have helped to dissipate stress and strain, making the rostral part of the skull less susceptible to bending and displacement, and this benefit may extend to other vertebrate clades that possess rhamphothecae. Keratinous beaks, paralleled by edentulism, thus represent an evolutionary innovation developed early in derived theropods to enhance cranial stability, distinct to postulated mass-saving benefits associated with the origin of flight.

Radiographic screening of edentulous patients: sense or nonsense? A risk-benefit analysis

International Nuclear Information System (INIS)

Keur, J.J.

1986-01-01

The benefits of radiographic examination of symptomless edentulous patients are presented. Based on data from the literature, an estimate of the risk of fatal malignancy from such a procedure is provided. Because the benefits are considerable and the risks low, a recommendation for selective screening of edentulous patients is made

Evaluation of palatal rugoscopy in dentulous and edentulous cases for human identification in forensic dentistry

Directory of Open Access Journals (Sweden)

Rogério José Scandiuzzi

2014-03-01

The search for identity is based on a set of characteristics, which defines the uniqueness of a person. Principles such as classificability, immutability, persistence, practicability and uniqueness must be considered when applying an identification technique. This study aimed to evaluate the use of palatal rugoscopy in dentulous and edentulous volunteers, with or without upper removable denture, for purposes of human identification. In this study 60 subjects were asked to give dental casts and photography of the upper dental arch, defined in the following groups: Group A (n = 30, edentulous patients with full upper removable dentures and Group B (n = 30, dentulous without upper removable partial denture. The rugoscopy analysis method used was Martins-dos-Santos classification, for checking the applicability and success in human identification. It was found that it is possible to use this technique and it has an application of 40% in the group A and 86.66% in the group B. In conclusion, the identification method by palatal rugoscopy is satisfactory for dentulous patients, however in cases of tooth loss and friction cases generated by prosthetic devices, the region of the palate lose its characteristics, but even then it is still possible to be applied.

Obturator prostheses in post-oncological maxillofacial patients: our experience

Directory of Open Access Journals (Sweden)

Edoardo Brauner

2014-12-01

Full Text Available Background: Surgical procedures for tumors of the paranasal sinus, palatal epithelium, minor salivary glands or osteosarcoma of the upper jaw require a partial or total maxillectomy of the upper jaw. When the surgical procedure and/or radiation therapy result in a communication, the solution is necessarily prosthetical, through a palatal obturator that recreates a partition between the oral and nasal cavities. Methods: Authors selected 32 post-oncological patients with the upper maxilla completely edentulous prosthetically rehabilitated with a palatal obturator. Results: No serious complications or adverse reactions were reported during the fabrication of surgical or definitive obturators. All patients stated to benefit the palatal obturator in terms of quality of life. Conclusion: Prosthetic rehabilitation of edentulous maxillectomy with oral communication is a demanding challenge for the prosthodontist. The goals of prosthetic rehabilitation include separation of oral and nasal cavities to allow adequate deglutition and articulation of teeth, restore midfacial soft tissue contour and a satisfactory esthetic outcome. When, for any reason, the patient is not a suitable candidate for an implant-retained overdenture, a total removable prosthesis should ensure the most comfort in terms of swallowing, phonation and aesthetics.

A Comparative Rugoscopic Study of the Dentate and Edentulous Individuals in the South Indian Population

Directory of Open Access Journals (Sweden)

Jagdish Prasad Rajguru

2014-01-01

Full Text Available This study analyzes the rugae pattern in dentulous and edentulous patients and also evaluates the association of rugae pattern between males and females. Aims and Objectives. This study aims to investigate rugae patterns in dentulous and edentulous patients of both sexes in South Indian population and to find whether palatoscopy is a useful tool in human identification. Materials and Methods. Four hundred outpatients from Sree Balaji Dental College and Hospital, Chennai, were included in the study. The study group was equally divided between the sexes, which was further categorized into 100 dentulous and edentulous patients, respectively. Results. The edentulous male showed the highest mean of wavy pattern and total absence of circular pattern while the edentulous female group showed the highest mean of curved pattern and total absence of nonspecific pattern, while dentate population showed similar value as that of the overall population such as straight, wavy, and curved patterns. Conclusion. The present study concludes that there is similar rugae pattern of distribution between male and female dentate population while there is varied pattern between the sexes of edentulous population. However, the most predominant patterns were straight, wavy, and circular patterns.

[Jaws of amphibians and reptiles].

Science.gov (United States)

Tanimoto, Masahiro

2005-04-01

Big jaws of amphibians and reptiles are mainly treated in this article. In amphibians enlarged skulls are for the big jaw in contrast with human's skulls for the brain. For example, famous fossils of Homo diluvii testis are ones of salamanders in fact. In reptiles, mosasaur jaws and teeth and their ecology are introduced for instance.

Vertical distraction of the severely resorbed edentulous mandible : An assessment of treatment outcome

NARCIS (Netherlands)

Raghoebar, Gerry M.; Stellingsma, Kees; Meijer, Henny J. A.; Vissink, Arjan

2008-01-01

Purpose: To assess the treatment outcome (implant survival, surgical complications, patient satisfaction) of vertical distraction of the severely resorbed edentulous mandible. Materials and Methods: Forty-six patients with severe resorption of the edentulous mandible (bone height 5 to 8 mm, median 6

Broken or dislocated jaw

Science.gov (United States)

... broken or dislocated jaw requires prompt medical attention. Emergency symptoms include difficulty breathing or heavy bleeding. ... safety equipment, such as a helmet when playing football, or using ... can prevent or minimize some injuries to the face or jaw.

Idiopathic Osteosclerosis of the Jaw in a Brazilian Population: a Retrospective Study

Directory of Open Access Journals (Sweden)

Elen de Souza Tolentino

2014-01-01

Full Text Available Objectives: To report cases of idiopathic osteosclerosis (IO, to review the literature on the subject, and to discuss its main characteristics, diagnosis, differential diagnosis, and treatment. Material and methods: Retrospective analysis of 354 panoramic radiographs, searching for IO, its size, shape, location, and noting patients’ demographic information. Literature review used Medline and Lilacs databases and the terms idiopathic osteosclerosis OR bone sclerosis OR dense bone island AND jaws. Results: IO was identified in 5.6% of the radiographs (n=20 patients, 22 foci. Patients were healthy, with an age ranging from 5 to 51 years (mean=29.8, with male-female ratio of 3:2. IOs were found mainly in the premolar/molar region, at root apices, between roots, away from the teeth, laterally to the tooth, and in edentulous areas. The distribution between right and left sides of the jaw was equal for the 22 foci, with only one case in the maxilla. IOs were localized, well-defined, radiopaque, mostly round or ovoid in shape, but sometimes irregular. In some cases, IOs were similar to condensing osteitis, but differential diagnosis also considered complex odontoma, focal cemento-osseous dysplasia, and residual roots. Twenty studies on the topic were reviewed. Conclusions: Incidence of IO in the Brazilian sample was 5.6%, with age ranging from 5 to 51 years (mean=29.8, and male-female ratio of 3:2. The radiopacities occurred in different locations, with significant prevalence in the mandible. The findings and the literature review corroborate the hypothesis that IO should be considered developmental variation of normal bone that does not require treatment.

Should edentulous patients be constrained to removable complete dentures? The use of dental implants to improve the quality of life for edentulous patients.

Science.gov (United States)

Turkyilmaz, Ilser; Company, Andrea M; McGlumphy, Edwin A

2010-03-01

Nowadays, there is some speculation among dental educators that the need for complete dentures will significantly decrease in the future and that training in their provision should be removed from the dental curriculum. To sensitise the reader to the functional shortcomings of complete denture therapy in the edentulous patient and present restorative options including implants to improve edentulous quality of life in these patients. Information retrieval followed a systematic approach using PubMed. English articles published from 1964 to 2008, in which the masticatory performance of patients with implant-supported dentures was assessed by objective methods and compared with performance with conventional dentures, were included. National epidemiological survey data suggested that the adult population in need of one or two complete dentures will increase from 35.4 million adults in 2000 to 37.9 million adults in 2020. Clinical studies have showed that the ratings of general satisfaction were significantly better in the patients treated with implant overdentures post-delivery compared with the complete denture users. In addition, the implant group gave significantly higher ratings on comfort, stability and ability to chew. Furthermore, patients who received mandibular implant overdentures had significantly fewer oral health-related quality of life problems than did the conventional group. Implant-supported dentures including either complete overdentures or a hybrid prosthesis significantly improve the quality of life for edentulous patients compared with conventional removable complete dentures. Therefore, the contemporary dental practitioner should consider other options as well as conventional removable complete dentures to restore edentulous patients.

Removable Partial Denture Supported by Implants with Prefabricated Telescopic Abutments - A Case Report

Science.gov (United States)

Sehgal, Komal

2014-01-01

Implants have been designed to rehabilitate edentulous patients with fixed prosthesis or implant supported overdentures. Implant-supported single crowns and fixed partial dentures have become successful treatment alternatives to removable and fixed partial dentures. However, it is common to have clinical situations which make it impossible to use conventional as well as implant supported fixed partial dentures. The implant supported removable partial dentures can be a treatment modality that offers the multitude of benefits of implant-based therapy—biologic, biomechanical, social, and psychological to such patients. The aim of this article is to present a case report describing the fabrication and advantages of removable partial denture supported by teeth and implants for a patient with long edentulous span. The patient was satisfied with his dentures in terms of function and aesthetics. Regular follow-up visits over a period of three years revealed that the periodontal condition of remaining natural dentition and peri-implant conditions were stable. There was no evidence of excessive residual ridge resorption or mobility of the teeth, nor were any visible changes in the bone levels of the natural teeth or implants noted on radiographs. PMID:25121066

Removable partial denture supported by implants with prefabricated telescopic abutments - a case report.

Science.gov (United States)

Kumar, Lalit; Sehgal, Komal

2014-06-01

Implants have been designed to rehabilitate edentulous patients with fixed prosthesis or implant supported overdentures. Implant-supported single crowns and fixed partial dentures have become successful treatment alternatives to removable and fixed partial dentures. However, it is common to have clinical situations which make it impossible to use conventional as well as implant supported fixed partial dentures. The implant supported removable partial dentures can be a treatment modality that offers the multitude of benefits of implant-based therapy-biologic, biomechanical, social, and psychological to such patients. The aim of this article is to present a case report describing the fabrication and advantages of removable partial denture supported by teeth and implants for a patient with long edentulous span. The patient was satisfied with his dentures in terms of function and aesthetics. Regular follow-up visits over a period of three years revealed that the periodontal condition of remaining natural dentition and peri-implant conditions were stable. There was no evidence of excessive residual ridge resorption or mobility of the teeth, nor were any visible changes in the bone levels of the natural teeth or implants noted on radiographs.

JAW CYSTS AND GUIDED BONE REGENERATION (a late complication after enucleation

Directory of Open Access Journals (Sweden)

Hristina Lalabonova

2013-10-01

Full Text Available Maxillary jaw bone possesses a high regenerative capacity. Yet sometimes the defects enucleation of jaw cysts leaves may regenerate only partially or not at all. For this reason some researchers advise treatment of the residual cavities after cystectomy using bone regeneration stimulation methods. We report a case of an atypical complication after enucleation of a maxillary cyst manifesting itself eight years after the initial treatment. The symptoms the patient reported were at first periodic sweating on the left sides of face and head. This was followed by a piercing pain in the left palpebral fissure radiating to the middle of the palate and felt in the left cheekbone, left eye and left supraorbital ridge. The patient has a history of maxillary cysts recurring three times and of three operations she had 20, 12 and 8 years previously. The multiple recurrences of the cysts after their enucleation indicates poor regenerative capacity of the body which resulted in the formation of cicatricial tissue. It is most probably this tissue that was responsible for the disruption of the nerve conduction capacity which can account for the reported symptoms. We filled the cavity with bone graft material which boosted the bone structure regeneration. Although maxillary jaws possess high regenerative capacity we advise the use of guided bone regeneration in cases of large bone defects that usually occur after enucleation of jaw cysts.

Influence of balanced occlusion in complete dentures on the decrease in reduction of an edentulous ridge

Directory of Open Access Journals (Sweden)

Poštić Srđan D.

2012-01-01

Full Text Available Background/Aim. Balanced occlusal arrangement of artificial teeth and balanced occlusion is a specific type of occlusion that preserves the stability of complete dentures. Balanced occlusion comprises realization of tooth contacts at the working side as well as at the balancing side, at the same time. The aim of this study was to assess the influence of balanced occlusal arrangement of artificial teeth on the decrease in reduction of edentulous alveolar ridge. Methods. A longitudinal study on 91 fully edentulous patients was conducted using their panoramic radiographs and parameters of vertical dimension of edentulous ridges. All the patients were clinically examined by the same and a qualified dental practitioner. Numerical values of parameters of vertical dimensions of edentulous ridges and lines were statistically processed and compared using the Student’s t-test. Results. Vertical dimensions and heights of edentulous ridges were different after comparison of parameters in complete denture wearers with balanced occlusion and complete denture wearers without bilaterally balanced occlusion, as well as between male and female edentulous patients. Statistically significant differences of heights were established in complete denture wearers’ with a set of artificial teeth without balanced occlusion, at the baseline and 12 months after wearing of complete dentures. Conclusion. Balanced occlusion is a favored occlusal design in setting of artificial teeth in conventional complete dentures, which preserves edentulous ridge and influence the stability of dentures.

A clinico-radiographic study to compare and co-relate sagittal condylar guidance determined by intraoral gothic arch tracing method and panoramic radiograph in completely edentulous patients.

Science.gov (United States)

Shetty, Sanath; Kunta, Mythili; Shenoy, Kamalakanth

2018-01-01

The purpose of this study was to compare and correlate sagittal condylar guidance determined by intraoral gothic arch tracing method and panoramic radiograph in edentulous patients. Twelve completely edentulous patients were selected by the inclusion and exclusion criteria. Conventional steps in the fabrication of complete denture till jaw relation were carried out. Intraoral gothic arch tracing and protrusive interocclusal records were obtained for each patient. Protrusive interocclusal record was used to program the Hanau Wide-Vue semi-adjustable articulator, thus obtaining the sagittal condylar guidance angle. Using RadiAnt DICOM software, on the orthopantomogram obtained for each patient in the study, two reference lines were drawn. The Frankfort's horizontal plane and the mean curvature line (joining the most superior and the inferior points on the glenoid fossa curvature) were drawn. The mean curvature line was extended to intersect the Frankfort's horizontal plane, thus obtaining the radiographic sagittal condylar guidance angle. The condylar guidance angles obtained by these two methods were compared and subjected to paired t -test. There was no statistically significant difference between the sagittal condylar guidance angles obtained between right and left sides with intraoral gothic arch tracing and radiographic methods ( P = 0.107 and 0.07, respectively). Within the limitations of this study, it was concluded that the protrusive condylar guidance angles obtained by panoramic radiograph may be used for programming semi-adjustable articulators.

The Use of Implants to Improve Removable Partial Denture Function.

Science.gov (United States)

Pimentel, Marcele Jardim; Arréllaga, Juan Pablo; Bacchi, Ataís; Del Bel Cury, Altair A

2014-12-01

The oral rehabilitation with conventional removable partial dentures in Kennedy class I patients allows continuous bone resorption, dislodgment of the prosthesis during the mastication caused by the resilience of the mucosa, and rotation of the prosthesis. Thus, the associations of distal implants become an attractive modality of treatment for these patients. This case report presented an association of removable partial dentures, milled crowns and osseointegrated implants to rehabilitate a partial edentulous patient. A removable partial denture associated with implants and metal-ceramic milled crowns can offer excellent esthetics, and will improve function and biomechanics, at a reduced cost.

[Studies on the standardization of parameters for jaw movement analysis--6 degree-of-freedom jaw movements analysis].

Science.gov (United States)

Takeuchi, Hisahiro; Bando, Eiichi; Abe, Susumu

2008-07-01

To establish standardized evaluating methods for jaw movements analysis. In this paper, we investigated evaluating parameters for 6 degree-of-freedom jaw movements data. Recorded data of jaw border movements from 20 male adults were employed as basic samples. The main parameters were as follows: 1. The displacement of an intercondylar midpoint: the length of a straight line between 2 positions of this point, the intercuspal position and other jaw position. 2. The angle of intercondylar axes: the angle between 2 position of the intercondylar axis, the intercuspal position and other jaw position. 3. The angle of incisal-condylar planes: the angle between 2 position of the plane, the intercuspal position and other jaw position (this plane was defined with the incisal point and condylar points of both sides 4. The mandibular motion range index: quantitative values calculated with 2 of 3 parameters described above. The mandibular motion range index showed a close correlation with respective projected areas of the incisal paths, with the projected area of sagittal border movements on the sagittal plane r = 0.82 (p movements on the frontal plane: left lateral border movements r = 0.92 (p movements r = 0.84 (p movements data and relative relationship between the intercuspal position and other jaw position. They were independent of reference coordinate systems and could measure jaw movement quantitatively.

Bone Height Changes of the Mandibular Edentulous Ridge in Screw Retained Versus Telescopic Restorations for Completely Edentulous Patients

Directory of Open Access Journals (Sweden)

Eman Helal

2017-01-01

CONCLUSION: Up to the limitations of this study both treatment options the screw retained and telescopic overdenture can be used for rehabilitation of completely edentulous patients. These cases must be followed for a longer period to have a definite answer regarding their efficiency in the long run.

Nasal mask ventilation is better than face mask ventilation in edentulous patients.

Science.gov (United States)

Kapoor, Mukul Chandra; Rana, Sandeep; Singh, Arvind Kumar; Vishal, Vindhya; Sikdar, Indranil

2016-01-01

Face mask ventilation of the edentulous patient is often difficult as ineffective seating of the standard mask to the face prevents attainment of an adequate air seal. The efficacy of nasal ventilation in edentulous patients has been cited in case reports but has never been investigated. Consecutive edentulous adult patients scheduled for surgery under general anesthesia with endotracheal intubation, during a 17-month period, were prospectively evaluated. After induction of anesthesia and administration of neuromuscular blocker, lungs were ventilated with a standard anatomical face mask of appropriate size, using a volume controlled anesthesia ventilator with tidal volume set at 10 ml/kg. In case of inadequate ventilation, the mask position was adjusted to achieve best-fit. Inspired and expired tidal volumes were measured. Thereafter, the face mask was replaced by a nasal mask and after achieving best-fit, the inspired and expired tidal volumes were recorded. The difference in expired tidal volumes and airway pressures at best-fit with the use of the two masks and number of patients with inadequate ventilation with use of the masks were statistically analyzed. A total of 79 edentulous patients were recruited for the study. The difference in expiratory tidal volumes with the use of the two masks at best-fit was statistically significant (P = 0.0017). Despite the best-fit mask placement, adequacy of ventilation could not be achieved in 24.1% patients during face mask ventilation, and 12.7% patients during nasal mask ventilation and the difference was statistically significant. Nasal mask ventilation is more efficient than standard face mask ventilation in edentulous patients.

Nutritional status in edentulous people as compared to age matched dentate individuals-a cross-sectional study

Directory of Open Access Journals (Sweden)

Sukhabogi Jagadeeswara Rao

2013-01-01

Full Text Available Objectives: To assess the nutritional status in completely edentulous subjects and to compare with age matched dentate individuals. Materials and Method: The study was carried out in 60 individuals divided into two groups. Group one consisted of 30 edentulous subjects and 30 dentate individuals formed the second group Body Mass Index (BMI, serum albumin and hemoglobin values were analyzed in both the groups. Independent sample t- test was employed to check for the difference between the groups and Pearson′s correlation was done to ascertain the association between the variables within the groups. Results: There was a significant difference in all the biomarkers evaluated in between the groups. The values were negatively correlated with the period of edentulism within the groups. Conclusion: Edentulous people had lower nutritional values than their dentate counterparts and maintaining a healthy and normal dentition may have significant bearing on the overall health of an individual. body mass index, serum albumin, malnutrition, edentulous, dental status

A new bite block for panoramic radiographs of anterior edentulous patients: A technical report.

Science.gov (United States)

Park, Jong-Woong; Symkhampha, Khanthaly; Huh, Kyung-Hoe; Yi, Won-Jin; Heo, Min-Suk; Lee, Sam-Sun; Choi, Soon-Chul

2015-06-01

Panoramic radiographs taken using conventional chin-support devices have often presented problems with positioning accuracy and reproducibility. The aim of this report was to propose a new bite block for panoramic radiographs of anterior edentulous patients that better addresses these two issues. A new panoramic radiography bite block similar to the bite block for dentulous patients was developed to enable proper positioning stability for edentulous patients. The new bite block was designed and implemented in light of previous studies. The height of the new bite block was 18 mm and to compensate for the horizontal edentulous space, its horizontal width was 7 mm. The panoramic radiographs using the new bite block were compared with those using the conventional chin-support device. Panoramic radiographs taken with the new bite block showed better stability and bilateral symmetry than those taken with the conventional chin-support device. Patients also showed less movement and more stable positioning during panoramic radiography with the new bite block. Conventional errors in panoramic radiographs of edentulous patients could be caused by unreliability of the chin-support device. The newly proposed bite block for panoramic radiographs of edentulous patients showed better reliability. Further study is required to evaluate the image quality and reproducibility of images with the new bite block.

Genetics Home Reference: hyperparathyroidism-jaw tumor syndrome

Science.gov (United States)

... Twitter Home Health Conditions Hyperparathyroidism-jaw tumor syndrome Hyperparathyroidism-jaw tumor syndrome Printable PDF Open All Close ... Javascript to view the expand/collapse boxes. Description Hyperparathyroidism-jaw tumor syndrome is a condition characterized by ...

Prosthetic rehabilitation of edentulous patient with limited oral access: A clinical report

Directory of Open Access Journals (Sweden)

Sandeep Kumar

2012-01-01

Full Text Available Microstomia may result from surgical treatment of orofacial neoplasms, cleft lips, maxillofacial trauma, burns, radiotherapy or scleroderma. A maximal oral opening that is smaller than the size of a complete denture can make prosthetic treatment challenging. This clinical report presents the prosthodontic management of a total edentulous patient with microstomia. Sectional mandibular and maxillary trays and foldable mandibular and maxillary denture were fabricated for the total edentulous patient.

Flexible thermoplastic denture base materials for aesthetical removable partial denture framework.

Science.gov (United States)

Singh, Kunwarjeet; Aeran, Himanshu; Kumar, Narender; Gupta, Nidhi

2013-10-01

Conventional fixed partial dentures, implant supported Fixed Partial Dentures (FDPs) and removable partial dentures are the most common treatment modalities for the aesthetic and functional rehabilitation of partially edentulous patients. Although implants and FDP have certain advantages over removable partial dentures, in some cases, removable partial dentures may be the only choice which is available. Removable cast partial dentures are used as definitive removable prostheses when indicated, but location of clasps may affect aesthetics. So, when patient is concerned about aesthetics, flexible partial dentures which is aesthetically superior to flipper and cast partial dentures, may be considered. But for the success of flexible removable partial denture, proper diagnosis, treatment planning and insertion technique of this prosthesis is very important, which have been thoroughly described in this article.

Edentulism and associated factors among community-dwelling middle-aged and elderly adults in China.

Science.gov (United States)

Ren, Chong; McGrath, Colman; Yang, Yanqi

2017-06-01

To investigate the prevalence of self-reported edentulism and its associated risk factors among community-dwelling adults aged 45 years and older in China. Data from the national baseline survey (2011-2012) of the China Health and Retirement Longitudinal Study (CHARLS) were used for this study (N = 17 167). Bivariate and multivariate logistic regressions were conducted to assess the predictors of edentulism. Models 1 and 2 were based on the whole sample. Models 3 and 4 were based on the subsample (N = 9933) from whom anthropometric and blood biomarker data were available. The prevalence of edentulism was 8.64% among Chinese adults aged 45 and above. As shown by Model 1, older age was a robust predictor for edentulism (odds ratio [OR] = 3.81 for people aged 55-64; OR = 11.22 for people aged 65-74; OR = 24.05 for people aged 75 and above). Other factors positively associated with edentulism included being female (OR = 1.25), rural residence (OR = 1.30), asthma (OR = 1.48), depression (OR = 1.20), reduced physical function (OR = 1.37) and current smoking status (OR = 1.36). People with higher educational levels (OR = 0.75 for people who can read and write; OR = 0.64 for people who obtained a junior high school education or above) and better-off economic status (OR = 0.80) were less likely to be edentate. The association between edentulism and age, educational level, economic status and physical function remained significant in Model 3, and in addition, being underweight appeared as another strong predictor (OR = 1.93). The estimated prevalence of edentulism and the identified associated factors will provide epidemiologic evidence for future research and interventions in the target population in China. © 2016 John Wiley & Sons A/S and The Gerodontology Association. Published by John Wiley & Sons Ltd.

Telescopic Partial Dentures-Concealed Technology

OpenAIRE

Bhagat, Tushar Vitthalrao; Walke, Ashwini Nareshchandra

2015-01-01

The ideal goal of good dentist is to restore the missing part of oral structure, phonetics, his look and the most important is restored the normal health of the patient, which is hampered due to less or insufficient intake of food. Removable partial denture (RPD) treatment option is considered as a notion, which precludes the inevitability of ?floating plastic? in edentulous mouth, that many times fail to fulfill the above essential of the patients. In modern dentistry, though the dental impl...

Swiveling Lathe Jaw Concept for Holding Irregular Pieces

Science.gov (United States)

David, J.

1966-01-01

Clamp holds irregularly shaped pieces in lathe chuck without damage and eliminates excessive time in selecting optimum mounting. Interchangeable jaws ride in standard jaw slots but swivel so that the jaw face bears evenly against the workpiece regardless of contour. The jaws can be used on both engine and turret lathes.

[Acrylic resin removable partial dentures].

Science.gov (United States)

de Baat, C; Witter, D J; Creugers, N H J

2011-01-01

An acrylic resin removable partial denture is distinguished from other types of removable partial dentures by an all-acrylic resin base which is, in principle, solely supported by the edentulous regions of the tooth arch and in the maxilla also by the hard palate. When compared to the other types of removable partial dentures, the acrylic resin removable partial denture has 3 favourable aspects: the economic aspect, its aesthetic quality and the ease with which it can be extended and adjusted. Disadvantages are an increased risk of caries developing, gingivitis, periodontal disease, denture stomatitis, alveolar bone reduction, tooth migration, triggering of the gag reflex and damage to the acrylic resin base. Present-day indications are ofa temporary or palliative nature or are motivated by economic factors. Special varieties of the acrylic resin removable partial denture are the spoon denture, the flexible denture fabricated of non-rigid acrylic resin, and the two-piece sectional denture. Furthermore, acrylic resin removable partial dentures can be supplied with clasps or reinforced by fibers or metal wires.

Impact of removable partial denture prosthesis on chewing efficiency

Science.gov (United States)

BESSADET, Marion; NICOLAS, Emmanuel; SOCHAT, Marine; HENNEQUIN, Martine; VEYRUNE, Jean-Luc

2013-01-01

Removable partial denture prostheses are still being used for anatomic, medical and economic reasons. However, the impact on chewing parameters is poorly described. Objectives The objective of this study was to estimate the impact of removable partial denture prosthesis on masticatory parameters. Material and Methods Nineteen removable partial denture prosthesis (RPDP) wearers participated in the study. Among them, 10 subjects were Kennedy Class III partially edentulous and 9 with posterior edentulism (Class I). All presented a complete and full dentate opposing arch. The subjects chewed samples of carrots and peanuts with and without their prosthesis. The granulometry of the expectorated boluses from carrot and peanuts was characterized by median particle size (D50), determined at the natural point of swallowing. Number of chewing cycles (CC), chewing time (CT) and chewing frequency (CF=CC/CT) were video recorded. Results With RPDP, the mean D50 values for carrot and peanuts were lower [Repeated Model Procedures (RMP), F=15, p<0.001] regardless of the type of Kennedy Class. For each food, mean CC, CT and CF values recorded decreased (RMP, F=18, F=9, and F=20 respectively, p<0.01). With or without RPD, the boluses' granulometry values were above the masticatory normative index (MNI) determined as 4,000 µm. Conclusion RPDP rehabilitation improves the ability to reduce the bolus particle size, but does not reestablish fully the masticatory function. Clinical relevance This study encourages the clinical improvement of oral rehabilitation procedure. PMID:24212983

Patterns of Mortality in Patients Treated with Dental Implants: A Comparison of Patient Age Groups and Corresponding Reference Populations.

Science.gov (United States)

Jemt, Torsten; Kowar, Jan; Nilsson, Mats; Stenport, Victoria

2015-01-01

Little is known about the relationship between implant patient mortality compared to reference populations. The aim of this study was to report the mortality pattern in patients treated with dental implants up to a 15-year period, and to compare this to mortality in reference populations with regard to age at surgery, sex, and degree of tooth loss. Patient cumulative survival rate (CSR) was calculated for a total of 4,231 treated implant patients from a single clinic. Information was based on surgical registers in the clinic and the National Population Register in Sweden. Patients were arranged into age groups of 10 years, and CSR was compared to that of the reference population of comparable age and reported in relation to age at surgery, sex, and type of jaw/dentition. A similar, consistent, general relationship between CSR of different age groups of implant patients and reference populations could be observed for all parameters studied. Completely edentulous patients presented higher mortality than partially edentulous patients (P age groups showed mortality similar to or higher than reference populations, while older patient age groups showed increasingly lower mortality than comparable reference populations for edentulous and partially edentulous patients (P age groups of patients compared to reference populations was observed, indicating higher patient mortality in younger age groups and lower in older groups. The reported pattern is not assumed to be related to implant treatment per se, but is assumed to reflect the variation in general health of a selected subgroup of treated implant patients compared to the reference population in different age groups.

Telemedicine consulting in the patient preparation and planning of prosthetic tooth replacement.

Science.gov (United States)

Mladenović, Dragan; Tosić, Goran; Zivković, Dusan; Djindjić, Natasa; Mladenović, Lidija; Mladenović, Sanja; Marković, Ivana

2013-09-01

In the management of edentulous spaces, there is a permanent need of a dentist-prosthetician in charge to consult other specialists. Modern telemedicine, based on powerful computer and telecomunication systems, offers an adequate answer to these challenges, being able to transfer and obtain clinical data and consultation information over large distances. Using smartphone or a computer, the teleconsultant acces the system, downloads and review the data and photographs and gave suggestions. The system then enables direct, real time contact with the consultant, chat, or directs them to contact each other by phone. We presented telemedicine consulting in the patient preparation and planning of prosthetic tooth replacement in 3 cases with different teleconsultation requirements: the first case for prosthetic rehabilitation of his upper teeth, the second one for prosthetic management of his partial edentulousness and "a growth on his gums" in the vestibular region of the frontal teeth and the third one for prosthetic management of total edentulousness of her upper jaw. We used the system of telemedicine in dentistry, established at the Faculty of Medicine in Kosovska Mitrovica. The operation was based on the computer application system XPA3 Online, computer networking and mobile smartphone network. All consultations were succefull with no need for further procedures in regional center. The use of a mobile smartphone has brought about the mobility and availability of teleconsultant specialists in an extent never seen before. Prostheticians are thus able to offer better service to their patients and improve the quality of management of partially or totally edentulous patients, especially in rural areas.

Osteonecrosis of the jaw after dental implant placement. A case report

Directory of Open Access Journals (Sweden)

J.L. Calvo-Guirado

2014-03-01

Full Text Available Background: In the past few years, the occurrence of an oral lesion, called osteonecrosis of the jaw, has increasingly been reported in patients undergoing treatment with systemic bisphosphonates (BPs; however, few papers dealing with oral biphosphonates related osteonecrosis of the jaws (BRONJ can be found in the literature. The purpose of the present case was to report an occurrence of BRONJ after implant insertion. Case report: Ten years ago, eight dental implants were inserted in the jaw of a 65-year-old female. After 5 years of treatment with alendronic acid, a breakdown of the oral mucosa covering the implants occurred with a purulent discharge in the left side of the jaw; periapical radiolucency was present around both distal implants. An en-block resection of the alveolar bone including the two implants was performed. Thirthy-five hyperbaric sessions were taken and no signs of recurrence of the lesion were observed after a follow-up of 20 months. Before the new implant insertion, the patient had suspended the treatment with alendronic acid for 6 months. At the interface of one of the implants, a gap was observed between bone and implant. This bone was non vital, and many osteocyte lacunae were empty. Moreover, this bone appeared to be partially demineralized. Conclusion: There is certainly a temporal association between oral BPs use and development of BRONJ, but a correlation does not necessarily mean causation. In patients undergoing oraltreatment, clinicians must be aware of the increased risk of implant failure.

Edentulism and dental prostheses in the elderly: impact on quality of life measured with EuroQol--visual analog scale (EQ-VAS).

Science.gov (United States)

Cano-Gutiérrez, Carlos; Borda, Miguel G; Arciniegas, Antonio J; Borda, Claudia X

2015-01-01

The objective of this study was to measure the impact of edentulism and dental prostheses on quality of life (QOL) in older adults in Bogota, Colombia. Edentulism is a frequent condition in older adults and has great impact on their QOL. No epidemiological data are currently available on edentulism among older adults in Colombia. Data were obtained from the SABE-Bogota study, a cross-sectional study conducted in 2012, and used to analyze the EQ-VAS (Visual Analog Scale) from the EuroQol instrument to measure the perception of quality of life (QOL) in relation to edentulism. The study included 2,000 individuals over 60 years old. The Spearman-Rho correlation was used to analyze the correlation between EQ-VAS and edentulism. Chi-Square, ANOVA and t-test were used to study the differences in EQ-VAS scores between edentulous and healthy subjects. Statistical significance was set at peducation were related to edentulism. Individuals with fewer teeth and dental prostheses had lower EQ-VAS scores (pmeasuring the perception of QOL in dental health scenarios. Edentulism significantly affects QOL in older adults and the use of dental prosthesis does not improve the perception of QOL.

Immediate versus early non-occlusal loading of dental implants placed flapless in partially edentulous patients. One-year results from a randomised controlled trial.

Science.gov (United States)

Merli, Mauro; Merli, Aldo; Bernardelli, Francesco; Lombardini, Francesco; Esposito, Marco

2008-01-01

To compare immediate versus early (6 weeks) non-occlusal loading of dental implants placed flapless in partially edentulous patients 1 year after loading. Sixty patients were randomised: 30 to the immediately loaded group and 30 to the early loaded group. In order to be immediately loaded, implants were inserted with a minimum torque of > or = 40Ncm. Implants were fully occlusally loaded after 6 months. Outcome measures were prosthesis and implant failures, and biological and biomechanical complications. Five implants in five patients randomised to the immediately loaded group did not reach the required primary implant stability. Three of these implants (two prostheses) were not immediately loaded. Two patients who were randomised to the early loaded group were immediately loaded erroneously. Implants in five patients of the early loaded group were conventionally loaded. No patient dropped out and there were no failures. Two complications occurred in the early and one in the immediately loaded group (no statistically significant difference), but were solved. The use of a flapless technique for placing dental implants in conjunction with non-occlusal immediate or early loading in selected patients can provide excellent clinical results. No differences were observed when comparing implants that were loaded immediately or early. Therefore, when a high primary implant stability is obtained, it might be preferable to load the implants immediately rather than waiting for a few weeks.

Effects of edentulism in obstructive sleep apnea syndrome ...

African Journals Online (AJOL)

Objectives: The purpose of this study was to investigate the effects of edentulism in obstructive sleep apnea syndrome (OSAS) patients. Materials and Methods: The study patients' were selected from the Gaziantep University Sleep Clinic and Orthodontic Department archives between the years of 2009 and 2011.

A cephalometric study to determine the plane of occlusion in completely edentulous patients.

Science.gov (United States)

Hindocha, Amit D; Vartak, Vikas N; Bhandari, Aruna J; Dudani, Mohit T

2013-01-01

Determination of the plane of occlusion in completely edentulous patients with the help of the ala-tragus line (Camper's plane) may be questioned. An attempt to devise an alternative method to determine the orientation of the plane of occlusion was made. Cephalometric analysis was used to identify whether a correlation exists between the plane of occlusion of dentulous Indian individuals and other stable cranial landmarks. A negative correlation was found to exist between the occlusal Plane-FH plane angle and the porion-nasion-anterior nasal spine (PoNANS) angle. From the derived mathematical correlation, it was concluded that the angulation of the occlusal plane in completely edentulous subjects may be determined by taking a cephalogram at the diagnostic stage. Further, the clinical applicability of the derived mathematical formula (while determining the plane of occlusion) was tested on completely edentulous patients.

Improved Prefrontal Activity and Chewing Performance as Function of Wearing Denture in Partially Edentulous Elderly Individuals: Functional Near-Infrared Spectroscopy Study

Science.gov (United States)

Kamiya, Kazunobu; Narita, Noriyuki; Iwaki, Sunao

2016-01-01

The purpose of this study was to elucidate the effects of wearing a denture on prefrontal activity during chewing performance. We specifically examined that activity in 12 elderly edentulous subjects [63.1±6.1 years old (mean ± SD)] and 12 young healthy controls (22.1±2.3 years old) using functional near-infrared spectroscopy (fNIRS) in order to evaluate the quality of prefrontal functionality during chewing performance under the conditions of wearing a denture and tooth loss, and then compared the findings with those of young healthy controls. fNIRS and electromyography were used simultaneously to detect prefrontal and masticatory muscle activities during chewing, while occlusal force and masticatory score were also examined by use of a food intake questionnaire. A significant increase in prefrontal activity was observed during chewing while wearing a denture, which was accompanied by increased masticatory muscle activity, occlusal force, and masticatory score, as compared with the tooth loss condition. Prefrontal activation during chewing while wearing a denture in the elderly subjects was not much different from that in the young controls. In contrast, tooth loss in the elderly group resulted in marked prefrontal deactivation, accompanied by decreased masticatory muscle activity, occlusal force, and masticatory score, as compared with the young controls. We concluded that intrinsic prefrontal activation during chewing with a denture may prevent prefrontal depression induced by tooth loss in elderly edentulous patients. PMID:27362255

Relevance of variations in the opposing dentition for the functionality of fixed and removable partial dentures: a systematic review.

Science.gov (United States)

Pommer, Bernhard; Krainhöfner, Martin; Watzek, Georg; Tepper, Gabor; Dintsios, Charalabos-Markos

2012-01-01

The aim of this systematic review was to evaluate the functionality of fixed and removable partial dentures as test interventions in relation to variations in the opposing dentition and their prosthetic restoration. The abstracts identified in the respective databases were screened independently by two investigators. RCTs and uncontrolled studies were considered, provided the patients were included consecutively and the confounding variables were adequately monitored. Seventeen papers were included. The study and publication quality was assessed using a "biometric quality" tool showing an overall poor quality. The reported outcomes, such as survival rates, were in each case obtained from a single study. Two possible trends could be deduced for the endpoint longevity: (a) the first trend in favor of removable partial dentures, compared to fixed partial dentures, with a fully edentulous opposing arch fitted with a removable prosthesis; (b) the second trend in favor of implant-supported partial dentures, compared to conventionally fixed partial dentures, with natural opposing dentition or with a removable partial denture in the opposing arch. No evidence could be generated as to whether, and if so how, variations in the opposing dentition have a bearing on the decision to fit a partially edentulous arch with a fixed or removable partial denture.

Relevance of Variations in the Opposing Dentition for the Functionality of Fixed and Removable Partial Dentures: A Systematic Review

Directory of Open Access Journals (Sweden)

Bernhard Pommer

2012-01-01

Full Text Available The aim of this systematic review was to evaluate the functionality of fixed and removable partial dentures as test interventions in relation to variations in the opposing dentition and their prosthetic restoration. The abstracts identified in the respective databases were screened independently by two investigators. RCTs and uncontrolled studies were considered, provided the patients were included consecutively and the confounding variables were adequately monitored. Seventeen papers were included. The study and publication quality was assessed using a “biometric quality” tool showing an overall poor quality. The reported outcomes, such as survival rates, were in each case obtained from a single study. Two possible trends could be deduced for the endpoint longevity: (a the first trend in favor of removable partial dentures, compared to fixed partial dentures, with a fully edentulous opposing arch fitted with a removable prosthesis; (b the second trend in favor of implant-supported partial dentures, compared to conventionally fixed partial dentures, with natural opposing dentition or with a removable partial denture in the opposing arch. No evidence could be generated as to whether, and if so how, variations in the opposing dentition have a bearing on the decision to fit a partially edentulous arch with a fixed or removable partial denture.

Treatment planning: implant-supported partial overdentures.

Science.gov (United States)

Chee, Winston W L

2005-04-01

When multiple anterior teeth are missing, many options of replacement are available. Traditionally, the choice was between a fixed or removable prostheses. Today, with the predictability of dental implants, the options of tooth replacement range from removable partial dentures to implant-supported fixed prostheses. The choice of which restoration that will best provide occlusion and esthetics depends on multiple factors including the number and location of missing teeth, the residual ridge form in relation to the replacement teeth, the relationship of the maxillary and mandibular anterior teeth, the condition of teeth adjacent to the edentulous span, the amount of bone available for implant placement, the patients "smile line" and display of teeth, lip support, and financial constraints. When there is minimal loss of the ridge contour, restorations that emerge from the ridge are the most functional and esthetic restorations, adhesive-type fixed partial dentures, conventional fixed partial dentures, and implant-supported restorations can be indicated with the choice of restoration dependent on a risk benefit and cost benefit analysis. When there is a loss of ridge contour due to residual ridge resorption or trauma, the decision becomes more complex as not only does the tooth structure need to be replaced, the ridge form also has to be replaced. (Figures 1 and 2). This can be assessed clinically as illustrated by Figures 1 and 2 where a dis crepancy in arch form and ridge form in relation to the adjacent teeth and/or opposing arch can be observed. Other considerations are lip support and display of the teeth when smiling. This article presents a case and rationale for implant-supported par tial overdentures. Many authors have written on the merits of com plete overdentures. The complete overdenture has proven to be an improvement over conventional complete prostheses with respect to chewing efficiency, patient comfort and satisfaction. In partial edentulism, the

Short-term retrospective case series of implant-assisted removable partial dentures with locator abutments.

Science.gov (United States)

Ortiz-Puigpelat, Octavi; Gargallo-Albiol, Jordi; Hernández-Alfaro, Federico; Cabratosa-Termes, Josep

2014-01-01

The purpose of this retrospective case series was to report on the clinical performance of implant-assisted removable partial dentures (IARPDs) with Locator abutments in different partial edentulism situations, with a mean follow-up period of 28.6 months. Twelve consecutive patients were treated with IARPDs. A total of 24 implants were placed in the edentulous area. Minimum follow-up period was 12 months. Overall patient satisfaction, health of peri-implant tissues, survival of implants and abutments, and prosthetic complications were reported. Overall implant survival was 91.6%; two implants failed. No major complications were reported-only one IARPD metal framework broke. No Locator abutment loosening was reported. Within the limitations of this retrospective study, treatment with IARPDs can improve the patient's function, phonetics, and esthetics without the need for extensive bone regeneration surgeries and prosthodontic rehabilitations. However, well-designed prospective clinical studies on IARPDs are needed to support their long-term use.

Morphology and morphometry of the human sublingual glands in mouth floor enlargements of edentulous patients

Directory of Open Access Journals (Sweden)

Josiane Costa Rodrigues de SA

2013-12-01

Full Text Available Asymptomatic mouth floor enlargements may be observed in edentulous patients. These masses, which protrude from the mouth floor, may complicate the fitting of dentures and require surgery. Whether this "entity" may be considered an anatomical variation of the mouth floor or represent specific alterations in the sublingual gland is not known. Objective: The aim of this work is to investigate the morphological and morphometric aspects of the sublingual glands of edentulous patients with mouth floor enlargements and compare the glands of these patients with the sublingual glands of human cadavers. Material and Methods: Microscopic evaluation was performed on human sublingual glands from edentulous patients with mouth floor enlargements (n=20 and edentulous cadavers (n=20. The patients and cadavers were of similar ages. The data were compared using Mann-Whitney U, Fisher's exact and Student's t tests (p0.05. Only the variables "autolysis" and "congested blood vessels" presented statistical difference between groups (p=0.014; p=0.043. The morphometric study revealed that the volume densities of acini, ducts, stroma and adipose tissue were similar between the groups (p>0.05. CONCLUSION: The microscopic characteristics of the sublingual glands in mouth floor enlargements in edentulous patients correspond to characteristics associated with the normal aging process. The glands are not pathological and represent an age-related alteration that occurs with or without the presence of the mouth floor enlargements.

Load transfer characteristics of unilateral distal extension removable partial dentures with polyacetal resin supporting components.

Science.gov (United States)

Jiao, T; Chang, T; Caputo, A A

2009-03-01

To photoelastically examine load transfer by unilateral distal extension removable partial dentures with supporting and retentive components made of the lower stiffness polyacetal resins. A mandibular photoelastic model, with edentulous space distal to the right second premolar and missing the left first molar, was constructed to determine the load transmission characteristics of a unilateral distal extension base removable partial denture. Individual simulants were used for tooth structure, periodontal ligament, and alveolar bone. Three designs were fabricated: a major connector and clasps made from polyacetal resin, a metal framework as the major connector with polyacetal resin clasp and denture base, and a traditional metal framework I-bar removable partial denture. Simulated posterior bilateral and unilateral occlusal loads were applied to the removable partial dentures. Under bilateral and left side unilateral loading, the highest stress was observed adjacent to the left side posterior teeth with the polyacetal removable partial denture. The lowest stress was seen with the traditional metal framework. Unilateral loads on the right edentulous region produced similar distributed stress under the denture base with all three designs but a somewhat higher intensity with the polyacetal framework. The polyacetal resin removable partial denture concentrated the highest stresses to the abutment and the bone. The traditional metal framework I-bar removable partial denture most equitably distributed force. The hybrid design that combined a metal framework and polyacetal clasp and denture base may be a viable alternative when aesthetics are of primary concern.

A 2-year report on maxillary and mandibular fixed partial dentures supported by Astra Tech dental implants. A comparison of 2 implants with different surface textures

DEFF Research Database (Denmark)

Karlsson, U; Gotfredsen, K; Olsson, C

1998-01-01

In 50 partially edentulous patients, 133 (48 maxillary; 85 mandibular) Astra Tech dental implants of 2 different surface textures (machined; TiO-blasted) were alternately installed, supporting 52 fixed partial dentures (FPDs). Before abutment connection 2 machined implants (1 mandibular; 1...

Florid cemento-osseous dysplasia: review of an uncommon fibro-osseous lesion of the jaw with important clinical implications.

Science.gov (United States)

Fenerty, Sarah; Shaw, Wei; Verma, Rahul; Syed, Ali B; Kuklani, Riya; Yang, Jie; Ali, Sayed

2017-05-01

Florid cemento-osseous dysplasia (FCOD) is a rare, benign, multifocal fibro-osseous dysplastic process affecting tooth-bearing areas of the jaw, characterized by replacement of normal trabecular bone with osseous tissue and dense acellular cementum in a fibrous stroma. It is one clinicopathologic variant in a spectrum of related non-neoplastic fibro-osseous lesions known as cemento-osseous dysplasias (CODs), thought to arise from elements of the periodontal ligament. Diagnosis primarily relies upon radiographic and clinical findings; unnecessary biopsy should be avoided, as inoculation with oral pathogens may precipitate chronic infection in these hypovascular lesions. Appropriate management of uncomplicated FCOD consists of periodic radiographic follow-up. Accordingly, it is important that both radiologists and clinicians performing endodontic interventions possess familiarity with this entity in order to prevent misdiagnosis and inappropriate intervention, which may result in a protracted clinical course. Lesions are usually asymptomatic in the absence of infection, typically discovered on routine dental radiographs or imaging performed for unrelated indications. Radiographically, the condition typically manifests as widespread non-expansile intraosseous masses of varying internal lucency and sclerosis that surround the root apices of vital teeth or edentulous areas in the posterior jaw. While all CODs share similar microscopic features, FCOD is distinguished by its multifocal distribution, involving two or more quadrants of the maxilla and mandible, often in a bilateral symmetric fashion. The vast majority of cases are sporadic, though few exhibit an autosomal dominant familial inheritance pattern. In this pictorial review, we discuss the radiologic characteristics of this entity, pertinent clinical and histologic features, differential diagnoses, and management options.

Association between socioeconomic and health factors and edentulism in people aged 65 and older - a population-based survey.

Science.gov (United States)

Olofsson, Hanna; Ulander, Eva Lena; Gustafson, Yngve; Hörnsten, Carl

2017-08-01

To study edentulism and use of dental services in a population-based sample of people aged 65 years and older from northern Sweden and western Finland. In 2010, people aged 65, 70, 75 and 80 years who were living in one of 32 municipalities in northern Sweden and western Finland were invited to answer a questionnaire as part of the Gerontological Regional Database (GERDA) study ( n = 6099). The questionnaire contained items related to socioeconomic status, general health and edentulism. The prevalence of edentulism was 34.9% in Finland, compared with 20.6% in Sweden ( p < 0.001), 31.9% in rural areas, compared with 20.9% in urban areas ( p < 0.001), and 25% overall. The prevalence of edentulism rose from 17.8% in 65-year-olds, 23.8% in 70-year-olds, 33.5% in 75-year-olds and 37.3% in 80-year-olds ( p < 0.001), and was 23.8% in women, compared with 27% in men ( p < 0.001). In multivariate models, edentulism was associated with lower educational level (odds ratio (OR) 2.87, 95% confidence interval (CI) 2.31-3.58), low income level (OR 1.7, CI 1.09-1.47), residence in a rural area (OR 1.43, CI 1.23-1.66), male sex (OR 1.30, CI 1.12-1.52), dependence in instrumental activities of daily living (OR 1.48, CI 1.25-1.74), social isolation (OR 1.52, CI 1.17-1.98) and poor self-experienced health (OR 1.38, CI 1.17-1.62). One-quarter of the total sample was edentulous, with a higher prevalence of edentulism in Finland than in Sweden and in rural than in urban areas. Edentulism was associated with socioeconomic, psychological and health-related factors. These findings could be used to inform preventive measures and identify people aged 65 years and older who are in need of oral care.

Implementation and commissioning of an integrated micro-CT/RT system with computerized independent jaw collimation

International Nuclear Information System (INIS)

Jensen, Michael D.; Hrinivich, W. Thomas; Jung, Jongho A.; Holdsworth, David W.; Drangova, Maria; Chen, Jeff; Wong, Eugene

2013-01-01

Purpose: To design, construct, and commission a set of computer-controlled motorized jaws for a micro-CT/RT system to perform conformal image-guided small animal radiotherapy.Methods: The authors designed and evaluated a system of custom-built motorized orthogonal jaws, which allows the delivery of off-axis rectangular fields on a GE eXplore CT 120 preclinical imaging system. The jaws in the x direction are independently driven, while the y-direction jaws are symmetric. All motors have backup encoders, verifying jaw positions. Mechanical performance of the jaws was characterized. Square beam profiles ranging from 2 × 2 to 60 × 60 mm 2 were measured using EBT2 film in the center of a 70 × 70 × 22 mm 3 solid water block. Similarly, absolute depth dose was measured in a solid water and EBT2 film stack 50 × 50 × 50 mm 3 . A calibrated Farmer ion chamber in a 70 × 70 × 20 mm 3 solid water block was used to measure the output of three field sizes: 50 × 50, 40 × 40, and 30 × 30 mm 2 . Elliptical target plans were delivered to films to assess overall system performance. Respiratory-gated treatment was implemented on the system and initially proved using a simple sinusoidal motion phantom. All films were scanned on a flatbed scanner (Epson 1000XL) and converted to dose using a fitted calibration curve. A Monte Carlo beam model of the micro-CT with the jaws has been created using BEAMnrc for comparison with the measurements. An example image-guided partial lung irradiation in a rat is demonstrated.Results: The averaged random error of positioning each jaw is less than 0.1 mm. Relative output factors measured with the ion chamber agree with Monte Carlo simulations within 2%. Beam profiles and absolute depth dose curves measured from the films agree with simulations within measurement uncertainty. Respiratory-gated treatments applied to a phantom moving with a peak-to-peak amplitude of 5 mm showed improved beam penumbra (80%–20%) from 3.9 to 0.8 mm.Conclusions: A

Implementation and commissioning of an integrated micro-CT/RT system with computerized independent jaw collimation

Energy Technology Data Exchange (ETDEWEB)

Jensen, Michael D. [Department of Medical Biophysics, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7 (Canada); Hrinivich, W. Thomas; Jung, Jongho A. [Department of Physics and Astronomy, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7 (Canada); Holdsworth, David W. [Imaging Research Laboratories, Robarts Research Institute, 100 Perth Drive, London, Ontario N6A 5K8 (Canada); Department of Medical Biophysics, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7 (Canada); Department of Surgery, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7 (Canada); Drangova, Maria [Imaging Research Laboratories, Robarts Research Institute, 100 Perth Drive, London, Ontario N6A 5K8, Canada and Department of Medical Biophysics, The University of Western Ontario 1151 Richmond Street, London, Ontario N6A 3K7 (Canada); Chen, Jeff [Department of Physics and Engineering, London Regional Cancer Program, London Health Sciences Centre, 800 Commissioners Road East, London, Ontario N6A 5W9 (Canada); Department of Medical Biophysics, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7 (Canada); Department of Oncology, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7 (Canada); Wong, Eugene [Department of Physics and Astronomy, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7 (Canada); Department of Medical Biophysics, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7 (Canada); Department of Oncology, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7 (Canada); Department of Physics and Engineering, London Regional Cancer Program, London Health Sciences Centre, 800 Commissioners Road East, London, Ontario N6A 5W9 (Canada)

2013-08-15

Purpose: To design, construct, and commission a set of computer-controlled motorized jaws for a micro-CT/RT system to perform conformal image-guided small animal radiotherapy.Methods: The authors designed and evaluated a system of custom-built motorized orthogonal jaws, which allows the delivery of off-axis rectangular fields on a GE eXplore CT 120 preclinical imaging system. The jaws in the x direction are independently driven, while the y-direction jaws are symmetric. All motors have backup encoders, verifying jaw positions. Mechanical performance of the jaws was characterized. Square beam profiles ranging from 2 × 2 to 60 × 60 mm{sup 2} were measured using EBT2 film in the center of a 70 × 70 × 22 mm{sup 3} solid water block. Similarly, absolute depth dose was measured in a solid water and EBT2 film stack 50 × 50 × 50 mm{sup 3}. A calibrated Farmer ion chamber in a 70 × 70 × 20 mm{sup 3} solid water block was used to measure the output of three field sizes: 50 × 50, 40 × 40, and 30 × 30 mm{sup 2}. Elliptical target plans were delivered to films to assess overall system performance. Respiratory-gated treatment was implemented on the system and initially proved using a simple sinusoidal motion phantom. All films were scanned on a flatbed scanner (Epson 1000XL) and converted to dose using a fitted calibration curve. A Monte Carlo beam model of the micro-CT with the jaws has been created using BEAMnrc for comparison with the measurements. An example image-guided partial lung irradiation in a rat is demonstrated.Results: The averaged random error of positioning each jaw is less than 0.1 mm. Relative output factors measured with the ion chamber agree with Monte Carlo simulations within 2%. Beam profiles and absolute depth dose curves measured from the films agree with simulations within measurement uncertainty. Respiratory-gated treatments applied to a phantom moving with a peak-to-peak amplitude of 5 mm showed improved beam penumbra (80%–20%) from 3.9 to

The Prevalence of Edentulism among Patients Over 35 Years of Age Referring to the Selected Dental Clinics in Qom City, Iran, 2014

Directory of Open Access Journals (Sweden)

mina hamian

2016-12-01

Full Text Available Backgroung and Objectives: Edentulism is a common phenomenon among the elderly, which its prevalence is one of the community health indicators. Edentulism leads to gastrointestinal diseases, esthetic defects, and reduction of social and psychological abilities. The aim of this study was to investigate the prevalence of edentulism among patients aged 35 years and over who referred to the selected dental clinics of Qom city. Methods: In this cross-sectional study, 394 patients (aged 35 years and over referring to the selected dental clinics of Qom city, 2014, were randomly selected. Before performing oral examination for each person, demographic characteristics, including age, sex, job, marital status, and economic status, as well as history of smoking, xerostomia, systemic diseases, oral hygiene, and causes for edentulism, were recorded in a questionnaire. Data were analyzed using descriptive statistics and chi-square test. The level of significance was set at p<0.05. Results: The prevalence of edentulism was 23.9%, which had a significant relationship with gender, and was higher in male gender. The results of independent t-test showed that the mean age was higher in edentulous subjects and was higher (56.6. The most cause of tooth loss (75% was tooth decay. Among edentulous individuals, 84% were under diploma and 52.6% had moderate economic status. Also, 71.9% of them were brushing rarely. Conclusion: According to the results, the prevalence of edentulism in Qom was high. Also, there was a significant relationship between edentulism and education level, smoking, caries, periodontal disease, economic status, occupation, xerostomia, oral hygiene, and systemic diseases.

Measurement of Mucosal Thickness in Denture-bearing Area of Edentulous Mandible

Directory of Open Access Journals (Sweden)

Jian Dong

2015-01-01

Full Text Available Background: The thickness of the alveolar mucosa influences the probability of the occurrence of denture-induced irritations. Thick denture-supporting tissues offer relief from mucosal tenderness and ulcers; however, the uniformity of the thickness across the entire mandibular alveolar mucosa cannot be accurately determined in edentulous patients. This study aimed to assess the mucosal thickness of the denture-bearing area in the edentulous mandible. Methods: Twenty-seven edentulous patients underwent cone-beam computed tomography scanning, wherein the patients wore a record base to retract soft tissues away from the alveolar mucosa. The measured regions were the central incisor (IC, lateral incisor (IL, canine (Ca, first premolar (P1, second premolar (P2, first molar (M1, and second molar (M2 regions. The thickness was measured in the alveolar ridge crest (T, buccal (B1-B4, and lingual (L1-L4 alveolar ridge mucosa. The average thickness of the mucosa at buccal sides (B and lingual sides (L were also assessed. Results: The differences in the mucosal thickness between the left and right sides were not significant. In the Ca-M2 regions, T was the thickest, and L3 was the thinnest of all the measured points in the same regions. L was significantly less than B in posterior regions (P < 0.01. On the other hand, M2 at L4 was thinnest of all the measured regions from Ca to M2 (P < 0.01, and was thicker than IC, IL, P1, and P2 at B2. Conclusions: Since the mucosal thickness of denture-bearing area in the edentulous mandible is not uniform; the tissue surface of the denture base or custom tray should be selectively relieved, which may reduce the risk of denture-induced irritations.

REHABILITATION OF COMPLETELY EDENTULOUS MANDIBULAR ARCH USING IMPLANT SUPPORTED FIXED PROSTHESIS - A CASE REPORT.

OpenAIRE

Kiran Kaushik; Pankaj Dhawan; Pankaj Madhukar; Piyush Tandan; Prateek Agarwal.

2018-01-01

Teeth are important structures in the oral cavity with many associated functions. Loss of teeth may be inevitable due to several reasons. Replacement of teeth should be done to restore the functions like mastication, phonetics, and esthetics. Modern dentistry aims to return patients to normal oral health and function in a predictable fashion. Satisfying a completely edentulous patient is always considered as a difficult task. Various treatment options for completely edentulous patients are av...

Telemedicine consulting in the patient preparation and planning of prosthetic tooth replacement

Directory of Open Access Journals (Sweden)

Mladenović Dragan

2013-01-01

Full Text Available Introduction. In the management of edentulous spaces, there is a permanent need of a dentist-prosthetician in charge to consult other specialists. Modern telemedicine, based on powerful computer and telecomunication systems, offers an adequate answer to these challenges, being able to transfer and obtain clinical data and consultation information over large distances. Using smartphone or a computer, the teleconsultant acces the system, downloads and review the data and photographs and gave suggestions. The system then enables direct, real time contact with the consultant, chat, or directs them to contact each other by phone. Case report. We presented telemedicine consulting in the patient preparation and planning of prosthetic tooth replacement in 3 cases with different teleconsultation requirements: the first case for prosthetic rehabilitation of his upper teeth, the second one for prosthetic management of his partial edentulousness and “a growth on his gums” in the vestibular region of the frontal teeth and the third one for prosthetic management of total edentulousness of her upper jaw. We used the system of telemedicine in dentistry, established at the Faculty of Medicine in Kosovska Mitrovica. The operation was based on the computer application system XPA3 Online, computer networking and mobile smartphone network. All consultations were succefull with no need for further procedures in regional center. Conclusion. The use of a mobile smartphone has brought about the mobility and availability of teleconsultant specialists in an extent never seen before. Prostheticians are thus able to offer better service to their patients and improve the quality of management of partially or totally edentulous patients, especially in rural areas.

Telescopic Partial Dentures-Concealed Technology.

Science.gov (United States)

Bhagat, Tushar Vitthalrao; Walke, Ashwini Nareshchandra

2015-09-01

The ideal goal of good dentist is to restore the missing part of oral structure, phonetics, his look and the most important is restored the normal health of the patient, which is hampered due to less or insufficient intake of food. Removable partial denture (RPD) treatment option is considered as a notion, which precludes the inevitability of "floating plastic" in edentulous mouth, that many times fail to fulfill the above essential of the patients. In modern dentistry, though the dental implants or fixed partial denture is the better options, but they have certain limitations. However, overdentures and particularly telescopic denture is the overlooked technology in dentistry that would be a boon for such needy patients. Telescopic denture is especially indicated in the distal edentulous area with minimum two teeth bilaterally present with a good amount of periodontal support. This treatment modality is sort of preventive prosthodontics remedy, which in a conservative manner preserve the remaining teeth and helps in conservation of alveolar bone ultimately. There are two tenets related to this option, one is constant conservation edentulous ridge around the retained tooth and the most important is the endless existence of periodontal sensory action that directs and monitor gnathodynamic task. In this option the primary coping or inner coping are cemented on the prepared tooth, and a similar removable outer or inner telescopic crown placed tightly by using a mechanism of tenso-friction, this is firmly attached to a removable RPD in place without moving or rocking of the prosthesis, which is the common compliant of almost all patients of RPD. Copings are also protecting the abutment from tooth decay and also offers stabilization and maintaining of the outer crown. The outer crown engages the inner coping and gives as an anchor for the remainder of the dentition. This work is the review of telescopic prosthesis which is well supported by the case discussion, and

Handling of Polyvinylsiloxane Versus Polyether for Implant Impressions.

Science.gov (United States)

Farhan, Daniel; Lauer, Wiebke; Heydecke, Guido; Aarabi, Ghazal; Reissmann, Daniel R

2016-01-01

This study compared polyvinylsiloxane with polyether in handling dental impressions. Each participant (N = 39) made four impressions, each a combination of pickup and reseating techniques with polyether or polyvinylsiloxane, of one implant cast representing a specific clinical situation (tooth gaps, limited residual dentition, or edentulous jaw). Handling of impressions was subsequently rated by using a 12-item questionnaire with 100-mm visual analog scales. While mean satisfaction scores were higher for polyvinylsiloxane than for polyether (69.5/63.0, P < .001), differences among subgroups were statistically significant only for pickup technique, limited residual dentition, and edentulous jaw. Implant impressions made with polyvinylsiloxane using a pickup technique seem to be the best option for most clinical situations.

Feasibility and Accuracy of Digitizing Edentulous Maxillectomy Defects: A Comparative Study.

Science.gov (United States)

Elbashti, Mahmoud E; Hattori, Mariko; Patzelt, Sebastian Bm; Schulze, Dirk; Sumita, Yuka I; Taniguchi, Hisashi

The aim of this study was to evaluate the feasibility and accuracy of using an intraoral scanner to digitize edentulous maxillectomy defects. A total of 20 maxillectomy models with two defect types were digitized using cone beam computed tomography. Conventional and digital impressions were made using silicone impression material and a laboratory optical scanner as well as a chairside intraoral scanner. The 3D datasets were analyzed using 3D evaluation software. Two-way analysis of variance revealed no interaction between defect types and impression methods, and the accuracy of the impression methods was significantly different (P = .0374). Digitizing edentulous maxillectomy defect models using a chairside intraoral scanner appears to be feasible and accurate.

21 CFR 872.2060 - Jaw tracking device.

Science.gov (United States)

2010-04-01

... the diagnosis of temporomandibular joint disorders and associated orofacial pain is a nonpowered or... § 872.9. (b) Jaw tracking device for interpretation of mandibular jaw positions for the diagnosis—(1...

Edentulation alters material properties of cortical bone in the human craniofacial skeleton: functional implications for craniofacial structure in primate evolution

Science.gov (United States)

Dechow, Paul C.; Wang, Qian; Peterson, Jill

2011-01-01

Skeletal adaptations to reduced function are an important source of skeletal variation and may be indicative of environmental pressures that lead to evolutionary changes. Humans serve as a model animal to investigate the effects of loss of craniofacial function through edentulation. In the human maxilla, it is known that edentulation leads to significant changes in skeletal structure such as residual ridge resorption and loss of cortical thickness. However, little is known about changes in bone tissue structure and material properties, which are also important for understanding skeletal mechanics but are often ignored. The aims of this study were to determine cortical material properties in edentulous crania and to evaluate differences with dentate crania and thus examine the effects of loss of function on craniofacial structure. Cortical bone samples from fifteen edentulous human skulls were measured for thickness and density. Elastic properties and directions of maximum stiffness were determined by using ultrasonic techniques. These data were compared to those from dentate crania reported in a previous investigation. Cortical bone from all regions of the facial skeleton of edentulous individuals is thinner than in dentate skulls. Elastic and shear moduli, and density are similar or greater in the zygoma and cranial vault of edentulous individuals, while these properties are less in the maxilla. Most cortical bone, especially in edentulous maxillae, has reduced directional orientation. The loss of significant occlusal loads following edentulation may contribute to the change in material properties and the loss of orientation over time during the normal process of bone remodeling. These results suggest that area-specific cortical microstructural changes accompany bone resorption following edentulation. They also suggest that functional forces are important for maintaining bone mass throughout the craniofacial skeleton, even in areas such as the browridges, which

Implant-supported removable partial dentures in the mandible

NARCIS (Netherlands)

Louwerse, Charlotte

2017-01-01

Conventional removable partial dentures (RPD) in a free-ending situation in the lower jaw (i.e. only front teeth left) have a poor reputation. Several problems like discomfort and functional problems are frequently encountered, resulting in dissatisfied patients and desperate dentists. By supporting

Optimization of Collimator Jaw Locations for the LHC

CERN Document Server

Kaltchev, D I; Servranckx, R V; Jeanneret, J B

1996-01-01

A highly effective collimation scheme is required in the LHC to limit heating of the vacuum chamber and superconducting magnets by protons either uncaptured at injection or scattered from the collision points. The proposed system would consist of one set of primary collimators followed by three sets of secondary collimators downstream to clean up protons scattered from the primaries. Each set of collimators would consist of four pairs of jaws - horizontal, vertical, and 45 o and 135 o skew. A study is reported of the optimization of the longitudinal positions of these jaws with the aim of minimizing the maximum betatron amplitudes of protons surviving the collimation system. This is performed using an analytical representation of the action of the jaws and is confirmed by tracking. Significant improvement can be obtained by omitting inactive jaws and adding skew jaws.

Self-aligning fixture used in lathe chuck jaw refacing

Science.gov (United States)

Linn, C. C.

1965-01-01

Self-aligning tool positions and rigidly holds lathe chuck jaws for refacing and truing of the clamping surface. The jaws clamp the fixture in the manner of clamping a workpiece. The fixture can be modified to accommodate four-jawed checks.

Monte Carlo-based simulation of dynamic jaws tomotherapy

Energy Technology Data Exchange (ETDEWEB)

Sterpin, E.; Chen, Y.; Chen, Q.; Lu, W.; Mackie, T. R.; Vynckier, S. [Department of Molecular Imaging, Radiotherapy and Oncology, Universite Catholique de Louvain, 54 Avenue Hippocrate, 1200 Brussels, Belgium and Department of Medical Physics, University of Wisconsin-Madison, Madison, Wisconsin 53705 (United States); TomoTherapy Inc., 1240 Deming Way, Madison, Wisconsin 53717 (United States); 21 Century Oncology., 1240 D' onofrio, Madison, Wisconsin 53719 (United States); TomoTherapy Inc., 1240 Deming Way, Madison, Wisconsin 53717 and Department of Medical Physics, University of Wisconsin-Madison, Madison, Wisconsin 53705 (United States); Department of Radiotherapy and Oncology, Universite Catholique de Louvain, St-Luc University Hospital, 10 Avenue Hippocrate, 1200 Brussels (Belgium)

2011-09-15

Purpose: Original TomoTherapy systems may involve a trade-off between conformity and treatment speed, the user being limited to three slice widths (1.0, 2.5, and 5.0 cm). This could be overcome by allowing the jaws to define arbitrary fields, including very small slice widths (<1 cm), which are challenging for a beam model. The aim of this work was to incorporate the dynamic jaws feature into a Monte Carlo (MC) model called TomoPen, based on the MC code PENELOPE, previously validated for the original TomoTherapy system. Methods: To keep the general structure of TomoPen and its efficiency, the simulation strategy introduces several techniques: (1) weight modifiers to account for any jaw settings using only the 5 cm phase-space file; (2) a simplified MC based model called FastStatic to compute the modifiers faster than pure MC; (3) actual simulation of dynamic jaws. Weight modifiers computed with both FastStatic and pure MC were compared. Dynamic jaws simulations were compared with the convolution/superposition (C/S) of TomoTherapy in the ''cheese'' phantom for a plan with two targets longitudinally separated by a gap of 3 cm. Optimization was performed in two modes: asymmetric jaws-constant couch speed (''running start stop,'' RSS) and symmetric jaws-variable couch speed (''symmetric running start stop,'' SRSS). Measurements with EDR2 films were also performed for RSS for the formal validation of TomoPen with dynamic jaws. Results: Weight modifiers computed with FastStatic were equivalent to pure MC within statistical uncertainties (0.5% for three standard deviations). Excellent agreement was achieved between TomoPen and C/S for both asymmetric jaw opening/constant couch speed and symmetric jaw opening/variable couch speed, with deviations well within 2%/2 mm. For RSS procedure, agreement between C/S and measurements was within 2%/2 mm for 95% of the points and 3%/3 mm for 98% of the points, where dose is

Monte Carlo-based simulation of dynamic jaws tomotherapy

International Nuclear Information System (INIS)

Sterpin, E.; Chen, Y.; Chen, Q.; Lu, W.; Mackie, T. R.; Vynckier, S.

2011-01-01

Purpose: Original TomoTherapy systems may involve a trade-off between conformity and treatment speed, the user being limited to three slice widths (1.0, 2.5, and 5.0 cm). This could be overcome by allowing the jaws to define arbitrary fields, including very small slice widths (<1 cm), which are challenging for a beam model. The aim of this work was to incorporate the dynamic jaws feature into a Monte Carlo (MC) model called TomoPen, based on the MC code PENELOPE, previously validated for the original TomoTherapy system. Methods: To keep the general structure of TomoPen and its efficiency, the simulation strategy introduces several techniques: (1) weight modifiers to account for any jaw settings using only the 5 cm phase-space file; (2) a simplified MC based model called FastStatic to compute the modifiers faster than pure MC; (3) actual simulation of dynamic jaws. Weight modifiers computed with both FastStatic and pure MC were compared. Dynamic jaws simulations were compared with the convolution/superposition (C/S) of TomoTherapy in the ''cheese'' phantom for a plan with two targets longitudinally separated by a gap of 3 cm. Optimization was performed in two modes: asymmetric jaws-constant couch speed (''running start stop,'' RSS) and symmetric jaws-variable couch speed (''symmetric running start stop,'' SRSS). Measurements with EDR2 films were also performed for RSS for the formal validation of TomoPen with dynamic jaws. Results: Weight modifiers computed with FastStatic were equivalent to pure MC within statistical uncertainties (0.5% for three standard deviations). Excellent agreement was achieved between TomoPen and C/S for both asymmetric jaw opening/constant couch speed and symmetric jaw opening/variable couch speed, with deviations well within 2%/2 mm. For RSS procedure, agreement between C/S and measurements was within 2%/2 mm for 95% of the points and 3%/3 mm for 98% of the points, where dose is greater than 30% of the prescription dose (gamma analysis

Accuracy and reproducibility of virtual edentulous casts created by laboratory impression scan protocols.

Science.gov (United States)

Peng, Lingyan; Chen, Li; Harris, Bryan T; Bhandari, Bikash; Morton, Dean; Lin, Wei-Shao

2018-04-24

Although computer-aided design and computer-aided manufacturing (CAD-CAM) complete removable dental prostheses (CRDPs) have gained popularity, conventional impressions are still common for CAD-CAM CRDP treatment. These need to be digitized and converted into virtual edentulous casts with a laboratory impression scan protocol during prosthesis fabrication. How this can best be accomplished is unclear. The purpose of this in vitro study was to compare the accuracy and reproducibility of virtual edentulous casts created by a dental laboratory laser scanner and a cone-beam computed tomography (CBCT) scanner with a digitized master cast. A master cast was digitized as the virtual reference cast. Ten polyvinyl siloxane impressions were made on the master cast and scanned with the dental laboratory laser scanner and CBCT scanner. The impressions were sprayed with antiglare spray and rescanned. Four groups of virtual study casts (N=40) were created from the impression scans. All virtual study casts and the reference cast were registered with surface-matching software, and the root mean square (RMS) values (representation of overall accuracy) and percentage of measurement data points within 1 standard deviation (SD) of mean RMS values (%, representation of overall reproducibility) among the 4 study groups were measured. Additionally, 95 numeric distance differences (representation of accuracy at each region) were measured in 5 distinct regions: the apex of the denture border, 6 mm from denture border, crest of the ridge, palate, and posterior palatal seal. The repeated-measures ANOVA and post hoc test (t grouping) were used to determine statistical differences (α=.05). The laboratory scanner group had a significantly larger RMS value (4.0 ±0.3 μm, Pvirtual edentulous casts, and the antiglare spray only significantly improved the accuracy and reproducibility of virtual edentulous casts created by the dental laboratory laser scanner. The accuracy of the virtual edentulous

Economic Evaluation of Implant-Supported Overdentures in Edentulous Patients: A Systematic Review.

Science.gov (United States)

Zhang, Qi; Jin, Xin; Yu, Mengliu; Ou, Guoming; Matsui, Hiroyuki; Liang, Xing; Sasaki, Keiichi

Edentulous patients benefit significantly from implant-supported overdenture prostheses. The purpose of this systematic review was to evaluate the cost-effectiveness of implant-supported overdentures (IODs) for edentulous patients. The search was limited to studies written in English and included an electronic and manual search through MEDLINE (Ovid, 1946 to November 2015), Embase (Ovid, 1966 to November 2015), Cochrane Central Register of Controlled Trials (CENTRAL) (to November 2015), and PubMed (to November 2015). Two investigators extracted the data and assessed the studies independently. No meta-analysis was conducted due to the high heterogeneity within the literature. Of the initial 583 selected articles, 10 studies involving 802 participants were included. Of these, 6 studies had a high risk of bias and the rest had an unclear risk of bias. Implant-supported prostheses were more cost-effective when compared to conventional dentures and fixed implant-supported prostheses. Overdentures supported by two implants and magnet attachment were reported as cost-effective. Implant-supported overdentures are a cost-effective treatment for edentulous patients. More clinical studies with appropriate scientific vigor are required to further assess the cost-effectiveness of implant-supported overdentures.

Stereotactic radiosurgery with an upper partial denture

International Nuclear Information System (INIS)

Tayama, Shusaku; Kunieda, Etsuo; Takeda, Atsushi; Takeda, Toshiaki; Oku, Yohei

2009-01-01

A 54-year-old male with partial denture underwent stereotactic radiosurgery with an infrared camera-guided system for a metastatic brain tumor arising from lung cancer. Although this method utilizes a biteplate mounted on the upper jaw to detect head movement, the patient only had four teeth in his upper jaw. In order to stabilize the biteplate, the maxillary denture was fixed to the biteplate with an autopolymerizing resin. In addition, the rest-occlusal position of the lower jaw was impressed on the inferior surface of the biteplate with an autopolymerizing resin. To assess reproducibility and stability, the distance between the left and right incus and left and right markers was measured during pre-planning, as well as before and after stereotactic irradiation. Wearing the biteplate ensures the accuracy of radiotherapy planning for the implementation of radiosurgery in patients who have many maxillary teeth missing. However, a large degree of error was observed when the biteplate was removed. (author)

Assessment of the prevalence index on signs of combination syndrome in patients treated at Bauru School of Dentistry, University of Sao Paulo

Directory of Open Access Journals (Sweden)

Milton Carlos Gonçalves Salvador

2007-02-01

Full Text Available A group of destructive changes occurring in jaws in patients with maxillary complete dentures and mandibular removable partial dentures (bilaterally has been described in the literature as the combination syndrome. However, this condition is not clinically observed in all patients. The aim of this study was to establish the prevalence index on signs of combination syndrome and to verify whether these changes also occurred in patients rehabilitated with a mandibular removable partial denture (unilaterally. Sample was composed of 44 patients, completely edentulous in the maxilla. Thirty-two patients had a Kennedy Class I removable partial denture and 12 a Kennedy Class II. Three major alterations were observed in 20.5% of the studied population. Nevertheless, these changes were present only in 25% of patients with Kennedy Class I removable partial denture. Based on the findings of this study, it can be concluded that patients with Kennedy Class II removable partial denture do not have similar signs that lead to the combination syndrome's condition.

Radiologic appearance of primary jaw lesions in children

Energy Technology Data Exchange (ETDEWEB)

Gupta, Malini; Kaste, Sue C. [Department of Diagnostic Imaging, St. Jude Children' s Research Hospital, Memphis, TN (United States); Hopkins, Kenneth P. [Department of Surgery, Division of Dentistry, St. Jude Children' s Research Hospital, Memphis, TN (United States)

2002-03-01

Background: The jaw (an unusual site of primary tumors in children and adolescents) has lesions often found incidentally by dentists on routine panoramic radiographs or during examination of a child who has swelling or tooth pain. Objective: This pictorial seeks to familiarize pediatric radiologists with the radiographic appearance of a variety of primary jaw lesions. Materials and methods: We retrospectively searched institutional records for cases of primary jaw lesions in children and adolescents. Jaw lesions were characterized as: I, well-circumscribed radiolucent lesions; II, lesions with mixed or variable appearance; III, poorly circumscribed radiolucent lesions; and IV, radiopaque lesions. Results: Although most oral and maxillofacial lesions in children are benign, a broad spectrum of tumors was identified; lesions may occur in patients with unrelated prior malignancy. Conclusion: Because radiologic studies may identify jaw lesions and direct further care, familiarity with the appearance of these entities is prudent. (orig.)

The relationships among jaw-muscle fiber architecture, jaw morphology, and feeding behavior in extant apes and modern humans.

Science.gov (United States)

Taylor, Andrea B; Vinyard, Christopher J

2013-05-01

The jaw-closing muscles are responsible for generating many of the forces and movements associated with feeding. Muscle physiologic cross-sectional area (PCSA) and fiber length are two architectural parameters that heavily influence muscle function. While there have been numerous comparative studies of hominoid and hominin craniodental and mandibular morphology, little is known about hominoid jaw-muscle fiber architecture. We present novel data on masseter and temporalis internal muscle architecture for small- and large-bodied hominoids. Hominoid scaling patterns are evaluated and compared with representative New- (Cebus) and Old-World (Macaca) monkeys. Variation in hominoid jaw-muscle fiber architecture is related to both absolute size and allometry. PCSAs scale close to isometry relative to jaw length in anthropoids, but likely with positive allometry in hominoids. Thus, large-bodied apes may be capable of generating both absolutely and relatively greater muscle forces compared with smaller-bodied apes and monkeys. Compared with extant apes, modern humans exhibit a reduction in masseter PCSA relative to condyle-M1 length but retain relatively long fibers, suggesting humans may have sacrificed relative masseter muscle force during chewing without appreciably altering muscle excursion/contraction velocity. Lastly, craniometric estimates of PCSAs underestimate hominoid masseter and temporalis PCSAs by more than 50% in gorillas, and overestimate masseter PCSA by as much as 30% in humans. These findings underscore the difficulty of accurately estimating jaw-muscle fiber architecture from craniometric measures and suggest models of fossil hominin and hominoid bite forces will be improved by incorporating architectural data in estimating jaw-muscle forces. Copyright © 2013 Wiley Periodicals, Inc.

Jaw-Dropping: Functional Variation in the Digastric Muscle in Bats.

Science.gov (United States)

Curtis, Abigail A; Santana, Sharlene E

2018-02-01

Diet and feeding behavior in mammals is strongly linked to the morphology of their feeding apparatus. Cranio-muscular morphology determines how wide, forcefully, and quickly the jaw can be opened or closed, which limits the size and material properties of the foods that a mammal can eat. Most studies of feeding performance in mammals have focused on skull form and jaw muscles involved in generating bite force, but few explore how jaw abduction is related to feeding performance. In this study, we explored how the morphology of the digastric muscle, the primary jaw abducting muscle in mammals, and its jaw lever mechanics are related to diet in morphologically diverse noctilionoid bats. Results showed that insectivorous bats have strong digastric muscles associated with proportionally long jaws, which suggests these species can open their jaws quickly and powerfully during prey capture and chewing. Short snouted frugivorous bats exhibit traits that would enable them to open their jaws proportionally wider to accommodate the large fruits that they commonly feed on. Our results support the hypothesis that digastric muscle and jaw morphology are correlated with diet in bats, and that our results may also apply to other groups of mammals. Anat Rec, 301:279-290, 2018. © 2018 Wiley Periodicals, Inc. © 2018 Wiley Periodicals, Inc.

Effect of telescopic distal extension removable partial dentures on oral health related quality of life and maximum bite force: A preliminary cross over study.

Science.gov (United States)

Elsyad, Moustafa Abdou; Mostafa, Aisha Zakaria

2018-01-01

This cross over study aimed to evaluate the effect of telescopic distal extension removable partial dentures on oral health related quality of life and maximum bite force MATERIALS AND METHODS: Twenty patients with complete maxillary edentulism and partially edentulous mandibles with anterior teeth only remaining were selected for this cross over study. All patients received complete maxillary dentures and mandibular partial removable dental prosthesis (PRDP, control). After 3 months of adaptation, PRDP was replaced with conventional telescopic partial dentures (TPD) or telescopic partial dentures with cantilevered extensions (TCPD) in a quasi-random method. Oral health related quality of life (OHRQoL) was measured using OHIP-14 questionnaire and Maximum bite force (MBF) was measured using a bite force transducer. Measurements were performed 3 months after using each of the following prostheses; PRDP, TPD, and TCPD. TCPD showed the OHIP-14 lowest scores (i.e., the highest patient satisfaction with their OHRQoL), followed by TPD, and PRDP showed the highest OHIP-14 scores (i.e., the lowest patient satisfaction with OHRQoL). TCPD showed the highest MBF (70.7 ± 3.71), followed by TPD (57.4 ± 3.43) and the lowest MBF (40.2 ± 2.20) was noted with PRDP. WITHIN The Limitations of This Study, Mandibular Telescopic Distal Extension Removable Partial Dentures with Cantilevered Extensions Were Associated with Improved Oral Health Related Quality of Life and Maximum Bite Force Compared to Telescopic or Conventional PRDP. Telescopic distal extension removable prostheses is an esthetic restoration in partially edentulous patients with free end saddle. This article describes the addition of cantilevered extensions of this prosthesis. The results showed that telescopic distal extension removable prostheses with cantilevered extensions were associated with improved oral health related quality of life and maximum bite force compared to telescopic or conventional RPDs

Changes in head and cervical-spine postures and EMG activities of masticatory muscles following treatment with complete upper and partial lower denture.

Science.gov (United States)

Salonen, M A; Raustia, A M; Huggare, J A

1994-10-01

A clinical stomatognathic, cephalometric and electromyographic (EMG) study was performed in relation to 14 subjects (10 women, 4 men), each with an edentulous maxilla and residual mandibular dentition before and six months after treatment with complete upper and partial lower dentures. The mean age of the subjects was 54.4 years (range 43-64 years). The mean period of edentulousness and age of dentures were 22.5 years (range 15-33 years) and 14.1 (range 1.5-30 years), respectively. Natural head position was recorded (using a fluid-level method) and measured from cephalograms. EMG activity was measured in relation to masseter and temporal muscles. A decrease in clinical dysfunction index was noted in 12 of 14 subjects (86%). There was no change in cervical inclination, but a slight extension of the head was noted after treatment. Rapid recovery of the masticatory muscles was reflected in increased EMG activity, especially when biting in the maximal intercuspal position. In cases of edentulous maxilla and residual mandibular anterior dentition, treatment with a complete upper and lower partial denture had a favorable effect on craniomandibular disorders and masticatory-muscle function.

Corrective Jaw Surgery

Medline Plus

Full Text Available ... in face, mouth and jaw surgery.™ What We Do Who We Are News Videos Contact Find a Surgeon What We Do Anesthesia Anesthesia Oral and maxillofacial surgeons are extensively ...

Edentulism trends among middle-aged and older adults in the United States: comparison of five racial/ethnic groups.

Science.gov (United States)

Wu, Bei; Liang, Jersey; Plassman, Brenda L; Remle, Corey; Luo, Xiao

2012-04-01

This study examined edentulism trends among adults aged 50 and above in five ethnic groups in the United States: Asians, African Americans, Hispanics, Native Americans, and non-Hispanic Caucasians. Data came from the National Health Interview Surveys between 1999 and 2008. Respondents included 616 Native Americans, 2,666 Asians, 15,295 African Americans, 13,068 Hispanics, and 86,755 Caucasians. In 2008, Native Americans had the highest predicated rate of edentulism (23.98%), followed by African Americans (19.39%), Caucasians (16.90%), Asians (14.22%), and Hispanics (14.18%). Overall, there was a significant downward trend in edentulism rates between 1999 and 2008 (OR = 0.97, 95% CI: 0.96, 0.98). However, compared with Caucasians, Native Americans showed a significantly less decline of edentulism during this period (OR = 1.10, 95% CI: 1.02, 1.19). While there was a downward trend in edentulism between 1999 and 2008, significant variations existed across racial/ethnic groups. Innovative public health programs and services are essential to prevent oral health diseases and conditions for minority populations who lack access to adequate dental care. Additionally, given the increasing numbers of adults retaining their natural teeth, interventions designed to assist individuals in maintaining healthy teeth becomes more critical. © 2011 John Wiley & Sons A/S.

Effects of Jaw Clenching and Jaw Alignment Mouthpiece Use on Force Production During Vertical Jump and Isometric Clean Pull.

Science.gov (United States)

Allen, Charles R; Fu, Yang-Chieh; Cazas-Moreno, Vanessa; Valliant, Melinda W; Gdovin, Jacob R; Williams, Charles C; Garner, John C

2018-01-01

Allen, CR, Fu, Y-C, Cazas-Moreno, V, Valliant, MW, Gdovin, JR, Williams, CC, and Garner, JC. Effects of jaw clenching and jaw alignment mouthpiece use on force production during vertical jump and isometric clean pull. J Strength Cond Res 32(1): 237-243, 2018-This study examined the effects of jaw clenching, a self-adapted, jaw-repositioning mouthpiece on force production during maximum countermovement vertical jump and maximum isometric midthigh clean pull assessments in an attempt to determine any ergogenic effect attributable to clenching, jaw-repositioning mouthpiece use, or the combination of both. Thirty-six male subjects performed vertical jump and isometric clean pull assessments from a force platform under various mouthpiece and clench conditions. A 3 × 2 (mouthpiece × clench) repeated-measures analysis of variance was conducted to analyze each of the following force production variables for both assessments: peak force, normalized peak force, and rate of force development. In addition, jump height was analyzed for the vertical jump. Results revealed improvements in peak force (F1,35 = 15.84, p ≤ 0.001, (Equation is included in full-text article.)= 0.31), normalized peak force (F1,35 = 16.28, p ≤ 0.001, (Equation is included in full-text article.)= 0.32), and rate of force development (F1,35 = 12.89, p = 0.001, (Equation is included in full-text article.)= 0.27) during the isometric clean pull assessment when participants maximally clenched their jaw, regardless of mouthpiece condition. There were no statistically significant differences in jump height, peak force, normalized peak force, or rate of force development during the vertical jump for any treatment condition. This study supports previous research demonstrating that the implementation of remote voluntary contractions such as jaw clenching can lead to concurrent activation potentiation and a resulting ergogenic effect during activities involving and requiring high-force production.

The virtual craniofacial patient: 3D jaw modeling and animation.

Science.gov (United States)

Enciso, Reyes; Memon, Ahmed; Fidaleo, Douglas A; Neumann, Ulrich; Mah, James

2003-01-01

In this paper, we present new developments in the area of 3D human jaw modeling and animation. CT (Computed Tomography) scans have traditionally been used to evaluate patients with dental implants, assess tumors, cysts, fractures and surgical procedures. More recently this data has been utilized to generate models. Researchers have reported semi-automatic techniques to segment and model the human jaw from CT images and manually segment the jaw from MRI images. Recently opto-electronic and ultrasonic-based systems (JMA from Zebris) have been developed to record mandibular position and movement. In this research project we introduce: (1) automatic patient-specific three-dimensional jaw modeling from CT data and (2) three-dimensional jaw motion simulation using jaw tracking data from the JMA system (Zebris).

Implant-assisted removable partial dentures as an alternative treatment for partial edentulism: a review of the literature.

Science.gov (United States)

Chatzivasileiou, Konstantinos; Kotsiomiti, Eleni; Emmanouil, Ioannis

2015-01-01

This study reviewed the current literature concerning implant-assisted removable partial dentures (RPDs) in order to present the existing knowledge about performance issues. An electronic search was conducted on the PubMed database for published English-language articles that contained information about implant-assisted RPDs. A review of these articles indicated that the combination of dental implants with RPDs constitutes a cost-efficient prosthetic protocol that can offer solutions to problematic aspects of treatment with removable partial dentures. Well-designed studies are still needed to provide robust evidence on critical issues, such as design guidelines, long-term survival of implants associated with RPDs, and their effect on patients' quality of life.

Immediate versus delayed loading of strategic mini dental implants for the stabilization of partial removable dental prostheses: a patient cluster randomized, parallel-group 3-year trial.

Science.gov (United States)

Mundt, Torsten; Al Jaghsi, Ahmad; Schwahn, Bernd; Hilgert, Janina; Lucas, Christian; Biffar, Reiner; Schwahn, Christian; Heinemann, Friedhelm

2016-07-30

Acceptable short-term survival rates (>90 %) of mini-implants (diameter implants as strategic abutments for a better retention of partial removable dental prosthesis (PRDP) are not available. The purpose of this study is to test the hypothesis that immediately loaded mini-implants show more bone loss and less success than strategic mini-implants with delayed loading. In this four-center (one university hospital, three dental practices in Germany), parallel-group, controlled clinical trial, which is cluster randomized on patient level, a total of 80 partially edentulous patients with unfavourable number and distribution of remaining abutment teeth in at least one jaw will receive supplementary min-implants to stabilize their PRDP. The mini-implant are either immediately loaded after implant placement (test group) or delayed after four months (control group). Follow-up of the patients will be performed for 36 months. The primary outcome is the radiographic bone level changes at implants. The secondary outcome is the implant success as a composite variable. Tertiary outcomes include clinical, subjective (quality of life, satisfaction, chewing ability) and dental or technical complications. Strategic implants under an existing PRDP are only documented for standard-diameter implants. Mini-implants could be a minimal invasive and low cost solution for this treatment modality. The trial is registered at Deutsches Register Klinischer Studien (German register of clinical trials) under DRKS-ID: DRKS00007589 ( www.germanctr.de ) on January 13(th), 2015.

Implant support for removable partial overdentures: a case report.

Science.gov (United States)

Halterman, S M; Rivers, J A; Keith, J D; Nelson, D R

1999-01-01

Functional stability and the preservation of remaining alveolar bone are primary, and often elusive, goals when restoring the partially edentulous arch. The incorporation of dental implants for the partial support of removable prostheses offers a practical adjunct in the fulfillment of these objectives. Planning for complex courses of treatment that include dental implants requires close coordination between the surgeon and the restorative dentist. Decisions that deal with type, location, size, number of implant fixtures, and design of the prosthesis are critical. All of these areas must be discussed and established as acceptable to the patient and each clinician before the initiation of treatment. In this report, we present a course of patient treatment in which a removable partial denture is supported by natural remaining teeth in conjunction with osseointegrated implants.

Corrective Jaw Surgery

Medline Plus

Full Text Available AAOMS - Oral and maxillofacial surgeons. The experts in face, mouth and jaw surgery.™ What We Do Who ... surgeons surgically treat the soft tissues of the face, mouth and gums to improve function, appearance and ...

Corrective Jaw Surgery

Medline Plus

Full Text Available ... Oral and maxillofacial surgeons. The experts in face, mouth and jaw surgery.™ What We Do Who We ... surgically treat the soft tissues of the face, mouth and gums to improve function, appearance and oral ...

Molecular decay of enamel matrix protein genes in turtles and other edentulous amniotes

Directory of Open Access Journals (Sweden)

Meredith Robert W

2013-01-01

Full Text Available Abstract Background Secondary edentulism (toothlessness has evolved on multiple occasions in amniotes including several mammalian lineages (pangolins, anteaters, baleen whales, birds, and turtles. All edentulous amniote clades have evolved from ancestors with enamel-capped teeth. Previous studies have documented the molecular decay of tooth-specific genes in edentulous mammals, all of which lost their teeth in the Cenozoic, and birds, which lost their teeth in the Cretaceous. By contrast with mammals and birds, tooth loss in turtles occurred in the Jurassic (201.6-145.5 Ma, providing an extended time window for tooth gene degradation in this clade. The release of the painted turtle and Chinese softshell turtle genomes provides an opportunity to recover the decayed remains of tooth-specific genes in Testudines. Results We queried available genomes of Testudines (Chrysemys picta [painted turtle], Pelodiscus sinensis [Chinese softshell turtle], Aves (Anas platyrhynchos [duck], Gallus gallus [chicken], Meleagris gallopavo [turkey], Melopsittacus undulatus [budgerigar], Taeniopygia guttata [zebra finch], and enamelless mammals (Orycteropus afer [aardvark], Choloepus hoffmanni [Hoffmann’s two-toed sloth], Dasypus novemcinctus [nine-banded armadillo] for remnants of three enamel matrix protein (EMP genes with putative enamel-specific functions. Remnants of the AMBN and ENAM genes were recovered in Chrysemys and retain their original synteny. Remnants of AMEL were recovered in both testudines, although there are no shared frameshifts. We also show that there are inactivated copies of AMBN, AMEL and ENAM in representatives of divergent avian lineages including Galloanserae, Passeriformes, and Psittaciformes, and that there are shared frameshift mutations in all three genes that predate the basal split in Neognathae. Among enamelless mammals, all three EMP genes exhibit inactivating mutations in Orycteropus and Choloepus. Conclusions Our results

Removable partial denture on osseointegrated implants and natural teeth.

Science.gov (United States)

Chang, Li-Ching; Wang, Jen-Chyan; Tasi, Chi-Cheng

2007-01-01

Implants have been designed to provide edentulous patients with fixed prostheses or overdentures. Recently, implant-supported fixed partial prostheses and single crowns have become successful treatment alternatives to removable and fixed partial dentures. However, few researchers have examined "removable partial dentures on implants and natural teeth". In this article, we report two patients fitted with "removable partial dentures on implants and natural teeth". The patients were satisfied with their dentures in terms of function and aesthetics. Regular follow-up visits revealed that the periodontal and peri-implant conditions were stable. There was no evidence of excessive intrusion or mobility of the teeth, nor were any visible changes in the bone levels of the natural teeth or implants noted on radiographs. Since the average duration of observation was about 38 months, further follow-up examinations are necessary to determine whether these dentures remain stable long-term.

Influence of adaptation of removable partial denture on masticatory performance.

Directory of Open Access Journals (Sweden)

Jorge Nakouzi

2016-11-01

Full Text Available Objective: To compare the masticatory performance (MP of patients with old removable partial denture (RPD, recently inserted RPD and already adapted RPD by means of the simple sieve test. Material and Methods: Twenty-nine adult (>18 years old volunteer patients were recruited, with lower and upper RPD, excluding total edentulous subjects in the upper and lower jaw, with temporomandibular disorders, severe periodontal disease, mental disability or systemic disease compromising the masticatory or nervous system. Dentures were designed and fabricated by an expert operator. MP was evaluated in old RPD (MP1, recently inserted RPD (MP2 and adapted RPD (MP3. The simple sieve test used was Edlund-Lamm in percentage of MP, using Optosil® Comfort condensation silicone tablets, with standard sizes (5.0x20mm. In each phase, the patient chewed the tablet with 20 masticatory strokes. The crushed fragments were dried at 80°C for 60 minutes and weighed on an analytical scale. A multiple vibration sieve analysis was performed, using sieves with opening sizes of 2.8mm and 1.4mm. Shapiro-Wilk test and Anova test with Bonferroni correction were performed. Results: It was observed that MP1 presented a mean of 8.40% (SD±5.59, MP2 a mean of 8.56% (SD±5.56, and MP3 a mean of 18.26% (SD±8.12. There was a significant difference (p<0.05 between the MP1-MP3 groups, as well as between the MP2-MP3 (p<0.05. Conclusion: There is a significant increase in MP thirty days after the insertion of RPD, checkups, and adjustments performed by the dentist.

Corrective Jaw Surgery

Medline Plus

Full Text Available ... It can also invite bacteria that lead to gum disease. Click here to find out more. Who We ... It can also invite bacteria that lead to gum disease. Click here to find out more. Corrective Jaw ...

OK-432 (Picibanil) sclerotherapy for recurrent dislocation of the temporomandibular joint in elderly edentulous patients: Case reports.

Science.gov (United States)

Matsushita, Kazuhiro; Abe, Takae; Fujiwara, Toshikatsu

2007-09-01

Dislocation of the temporomandibular joint (TMJ) is a thorny problem not only for a patient but also a doctor. Especially for the elderly edentulous patients, it is very hard to treat the condition although there are many surgical and non-surgical procedures. We successfully treated it in two elderly edentulous patients by injection of OK-432 as a sclerosing agent.

Jaw-muscle fiber architecture in tufted capuchins favors generating relatively large muscle forces without compromising jaw gape

Science.gov (United States)

Taylor, Andrea B.; Vinyard, Christopher J.

2009-01-01

Cebus apella is renowned for its dietary flexibility and capacity to exploit hard and tough objects. Cebus apella differs from other capuchins in displaying a suite of craniodental features that have been functionally and adaptively linked to their feeding behavior, particularly the generation and dissipation of relatively large jaw forces. We compared fiber architecture of the masseter and temporalis muscles between the tufted capuchin (C. apella; n = 12 ) and two “untufted” capuchins (C. capuchinus, n = 3; C. albifrons, n = 5). These three species share broadly similar diets, but tufted capuchins occasionally exploit mechanically challenging tissues. We tested the hypothesis that C. apella exhibits architectural properties of their jaw muscles that facilitate relatively large forces, including relatively greater physiologic cross-sectional areas (PCSA), more pinnate fibers, and lower ratios of mass to tetanic tension (Mass/P0). Results show some evidence supporting these predictions, as C. apella has relatively greater superficial masseter, whole masseter, and temporalis PCSAs, significantly so only for the temporalis following Bonferroni adjustment. Capuchins did not differ in pinnation angle or Mass/P0. As an architectural trade-off between maximizing muscle force and muscle excursion/contraction velocity, we also tested the hypothesis that C. apella exhibits relatively shorter muscle fibers. Contrary to our prediction, there are no significant differences in relative fiber lengths between tufted and untufted capuchins. Therefore, we attribute the relatively greater PCSAs in C. apella primarily to their larger muscle masses. These findings suggest that relatively large jaw-muscle PCSAs can be added to the suite of masticatory features that have been functionally linked to the exploitation of a more resistant diet by C. apella. By enlarging jaw-muscle mass to increase PCSA, rather than reducing fiber lengths and increasing pinnation, tufted capuchins appear

Prevalence of Loss of All Teeth (Edentulism and Associated Factors in Older Adults in China, Ghana, India, Mexico, Russia and South Africa

Directory of Open Access Journals (Sweden)

Karl Peltzer

2014-10-01

Full Text Available Little information exists about the loss of all one’s teeth (edentulism among older adults in low- and middle-income countries. This study examines the prevalence of edentulism and associated factors among older adults in a cross-sectional study across six such countries. Data from the World Health Organization (WHO’s Study on global AGEing and adult health (SAGE Wave 1 was used for this study with adults aged 50-plus from China (N = 13,367, Ghana (N = 4724, India (N = 7150, Mexico (N = 2315, Russian Federation (N = 3938 and South Africa (N = 3840. Multivariate regression was used to assess predictors of edentulism. The overall prevalence of edentulism was 11.7% in the six countries, with India, Mexico, and Russia has higher prevalence rates (16.3%–21.7% than China, Ghana, and South Africa (3.0%–9.0%. In multivariate logistic analysis sociodemographic factors (older age, lower education, chronic conditions (arthritis, asthma, health risk behaviour (former daily tobacco use, inadequate fruits and vegetable consumption and other health related variables (functional disability and low social cohesion were associated with edentulism. The national estimates and identified factors associated with edentulism among older adults across the six countries helps to identify areas for further exploration and targets for intervention.

Prevalence of loss of all teeth (edentulism) and associated factors in older adults in China, Ghana, India, Mexico, Russia and South Africa.

Science.gov (United States)

Peltzer, Karl; Hewlett, Sandra; Yawson, Alfred E; Moynihan, Paula; Preet, Raman; Wu, Fan; Guo, Godfrey; Arokiasamy, Perianayagam; Snodgrass, James J; Chatterji, Somnath; Engelstad, Mark E; Kowal, Paul

2014-10-30

Little information exists about the loss of all one's teeth (edentulism) among older adults in low- and middle-income countries. This study examines the prevalence of edentulism and associated factors among older adults in a cross-sectional study across six such countries. Data from the World Health Organization (WHO's) Study on global AGEing and adult health (SAGE) Wave 1 was used for this study with adults aged 50-plus from China (N = 13,367), Ghana (N = 4724), India (N = 7150), Mexico (N = 2315), Russian Federation (N = 3938) and South Africa (N = 3840). Multivariate regression was used to assess predictors of edentulism. The overall prevalence of edentulism was 11.7% in the six countries, with India, Mexico, and Russia has higher prevalence rates (16.3%-21.7%) than China, Ghana, and South Africa (3.0%-9.0%). In multivariate logistic analysis sociodemographic factors (older age, lower education), chronic conditions (arthritis, asthma), health risk behaviour (former daily tobacco use, inadequate fruits and vegetable consumption) and other health related variables (functional disability and low social cohesion) were associated with edentulism. The national estimates and identified factors associated with edentulism among older adults across the six countries helps to identify areas for further exploration and targets for intervention.

Specification of jaw identity by the Hand2 transcription factor

Science.gov (United States)

Funato, Noriko; Kokubo, Hiroki; Nakamura, Masataka; Yanagisawa, Hiromi; Saga, Yumiko

2016-01-01

Acquisition of the lower jaw (mandible) was evolutionarily important for jawed vertebrates. In humans, syndromic craniofacial malformations often accompany jaw anomalies. The basic helix-loop-helix transcription factor Hand2, which is conserved among jawed vertebrates, is expressed in the neural crest in the mandibular process but not in the maxillary process of the first branchial arch. Here, we provide evidence that Hand2 is sufficient for upper jaw (maxilla)-to-mandible transformation by regulating the expression of homeobox transcription factors in mice. Altered Hand2 expression in the neural crest transformed the maxillae into mandibles with duplicated Meckel’s cartilage, which resulted in an absence of the secondary palate. In Hand2-overexpressing mutants, non-Hox homeobox transcription factors were dysregulated. These results suggest that Hand2 regulates mandibular development through downstream genes of Hand2 and is therefore a major determinant of jaw identity. Hand2 may have influenced the evolutionary acquisition of the mandible and secondary palate. PMID:27329940

Digital versus conventional implant impressions for edentulous patients: accuracy outcomes.

Science.gov (United States)

Papaspyridakos, Panos; Gallucci, German O; Chen, Chun-Jung; Hanssen, Stijn; Naert, Ignace; Vandenberghe, Bart

2016-04-01

To compare the accuracy of digital and conventional impression techniques for completely edentulous patients and to determine the effect of different variables on the accuracy outcomes. A stone cast of an edentulous mandible with five implants was fabricated to serve as master cast (control) for both implant- and abutment-level impressions. Digital impressions (n = 10) were taken with an intraoral optical scanner (TRIOS, 3shape, Denmark) after connecting polymer scan bodies. For the conventional polyether impressions of the master cast, a splinted and a non-splinted technique were used for implant-level and abutment-level impressions (4 cast groups, n = 10 each). Master casts and conventional impression casts were digitized with an extraoral high-resolution scanner (IScan D103i, Imetric, Courgenay, Switzerland) to obtain digital volumes. Standard tessellation language (STL) datasets from the five groups of digital and conventional impressions were superimposed with the STL dataset from the master cast to assess the 3D (global) deviations. To compare the master cast with digital and conventional impressions at the implant level, analysis of variance (ANOVA) and Scheffe's post hoc test was used, while Wilcoxon's rank-sum test was used for testing the difference between abutment-level conventional impressions. Significant 3D deviations (P impressions (P > 0.001). Digital implant impressions are as accurate as conventional implant impressions. The splinted, implant-level impression technique is more accurate than the non-splinted one for completely edentulous patients, whereas there was no difference in the accuracy at the abutment level. The implant angulation up to 15° did not affect the accuracy of implant impressions. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Multiple myeloma of the jaw: A case report

Directory of Open Access Journals (Sweden)

Shubhasini A Raghavan

2014-01-01

Full Text Available Multiple myeloma is a systemic B-cell lymphoproliferative disease that causes osteolytic lesions in the vertebra, ribs, pelvic bone, skull and jaw. Rarely jaw lesions are seen as the first sign in multiple myeloma. This is a case report with follow up of a 57-year-old female patient, previously treated for osteoporosis, who presented with a swelling of the jaw. On radiographic examination, she was found to have osteolytic lesions in the mandible and skull bones. These conventional aids led to the diagnosis of multiple myeloma thereby proving that the osteoporotic lesions were a part of the spectrum of multiple myeloma. The patient underwent chemotherapy and is currently on follow-up. This case report emphasizes the importance of early diagnosis of multiple myeloma in the jaw using readily available technologies and illustrates the contribution that oral assessment can provide.

[Size of lower jaw as an early indicator of skeletal class III development].

Science.gov (United States)

Stojanović, Zdenka; Nikodijević, Angelina; Udovicić, Bozidar; Milić, Jasmina; Nikolić, Predrag

2008-08-01

Malocclusion of skeletal class III is a complex abnormality, with a characteristic sagital position of the lower jaw in front of the upper one. A higher level of prognatism of the lower jaw in relation to the upper one can be the consequence of its excessive length. The aim of this study was to find the differences in the length of the lower jaw in the children with skeletal class III and the children with normal sagital interjaw relation (skeletal class I) in the period of mixed dentition. After clinical and x-ray diagnostics, profile tele-x-rays of the head were analyzed in 60 examinees with mixed dentition, aged from 6 to 12 years. The examinees were divided into two groups: group 1--the children with skeletal class III and group 2--the children with skeletal class I. The length of the lower jaw, upper jaw and cranial base were measured. The proportional relations between the lengths measured within each group were established and the level of difference in the lengths measured and their proportions between the groups were estimated. No significant difference between the groups was found in the body length, ramus and the total length of the lower jaw. Proportional relation between the body length and the length of the lower jaw ramus and proportional relation between the forward cranial base and the lower jaw body were not significantly different. A significant difference was found in proportional relations of the total length of the lower jaw with the total lengths of cranial base and the upper jaw and proportional relation of the length of the lower and upper jaw body. Of all the analyzed parameters, the following were selected as the early indicators of the development of skeletal class III on the lower jaw: greater total length of the lower jaw, proportional to the total lengths of cranial base and theupper jaw, as well as greater length of the lower jaw body, proportional to the length of the upper jaw body.

Multidetector computed tomography of jaw lesions in children and adolescents

International Nuclear Information System (INIS)

Gadodia, A.; Seith, A.; Sharma, R.; Choudhury, A.R.; Bhutia, O.; Gupta, A.

2010-01-01

Full text: Jaw lesions in paediatric and adolescent population are uncommon and can arise in odontogenic or non-odontogenic tissues. With the advent of multidetector computed tomography (MDCT), algorithm for imaging jaw lesions has changed dramatically. This pictorial essay describes the imaging appearance of commonly encountered jaw lesions in children and adolescents with emphasis on MDCT findings

Evolutionary Trends in the Jaw Adductor Mechanics of Ornithischian Dinosaurs.

Science.gov (United States)

Nabavizadeh, Ali

2016-03-01

Jaw mechanics in ornithischian dinosaurs have been widely studied for well over a century. Most of these studies, however, use only one or few taxa within a given ornithischian clade as a model for feeding mechanics across the entire clade. In this study, mandibular mechanical advantages among 52 ornithischian genera spanning all subclades are calculated using 2D lever arm methods. These lever arm calculations estimate the effect of jaw shape and difference in adductor muscle line of action on relative bite forces along the jaw. Results show major instances of overlap between taxa in tooth positions at which there was highest mechanical advantage. A relatively low bite force is seen across the tooth row among thyreophorans (e.g., stegosaurs and ankylosaurs), with variation among taxa. A convergent transition occurs from a more evenly distributed bite force along the jaw in basal ornithopods and basal marginocephalians to a strong distal bite force in hadrosaurids and ceratopsids, respectively. Accordingly, adductor muscle vector angles show repeated trends from a mid-range caudodorsal orientation in basal ornithischians to a decrease in vector angles indicating more caudally oriented jaw movements in derived taxa (e.g., derived thyreophorans, basal ornithopods, lambeosaurines, pachycephalosaurs, and derived ceratopsids). Analyses of hypothetical jaw morphologies were also performed, indicating that both the coronoid process and lowered jaw joint increase moment arm length therefore increasing mechanical advantage of the jaw apparatus. Adaptive trends in craniomandibular anatomy show that ornithischians evolved more complex feeding apparatuses within different clades as well as morphological convergences between clades. © 2016 Wiley Periodicals, Inc.

Segmental sandwich osteotomy and tunnel technique for three-dimensional reconstruction of the jaw atrophy: a case report.

Science.gov (United States)

Santagata, Mario; Sgaramella, Nicola; Ferrieri, Ivo; Corvo, Giovanni; Tartaro, Gianpaolo; D'Amato, Salvatore

2017-12-01

A three-dimensionally favourable mandibular bone crest is desirable to be able to successfully implant placement to meet the aesthetic and functional criteria in the implant-prosthetic rehabilitation. Several surgical procedures have been advocated for bone augmentation of the atrophic mandible, and the sandwich osteotomy is one of these techniques. The aim of the present case report was to assess the suitability of segmental mandibular sandwich osteotomy combined with a tunnel technique of soft tissue. Based on our knowledge, nobody described before the sandwich osteotomy with tunnel technique to improve the healing of the wound and meet the dimensional requirements of preimplant bone augmentation in cases of a severely atrophic mandible. A 59-year-old woman with a severely atrophied right mandible was treated with the sandwich osteotomy technique filled with autologous bone graft harvested by a cortical bone collector from the ramus. Clinical examination revealed that the mandible was edentulous bilaterally from the first molar to the second molar region. Radiographically, atrophy of the mandibular alveolar ridge in the same teeth site was observed. We began to treat the right side. A horizontal osteotomy of the edentulous mandibular bone was then made with a piezoelectric device after tunnel technique of the soft tissue. The segmental mandibular sandwich osteotomy (SMSO) was finished by two (mesial and distal) slightly divergent vertical osteotomies. The entire bone fragment was displaced cranially, and the desirable position was obtained. The gap was filled completely with autologous bone chips harvested from the mandibular ramus through a cortical bone collector. No barrier membranes were used to protect the grafts. The vertical incisions were closing with interruptive suturing of the flaps with a resorbable material. In this way, the suture will not fall on the osteotomy line of the jaw; the result will be a better predictability of soft and hard tissue

Angiogenesis in the reparatory mucosa of the mandibular edentulous ridge is driven by endothelial tip cells.

Science.gov (United States)

Stănescu, Ruxandra; Didilescu, Andreea Cristiana; Jianu, Adelina Maria; Rusu, M C

2012-01-01

Sprouting angiogenesis is led by specialized cell--the endothelial tip cells (ETCs) which can be targeted by pro- or anti-angiogenic therapies. We aimed to perform a qualitative study in order to assess the guidance by tip cells of the endothelial sprouts in the repairing mucosa of the edentulous mandibular crest. Mucosa of the mandibular edentulous ridge was collected from six adult patients, prior to healing abutment placement (second surgery). Slides were prepared and immunostained with antibodies for CD34 and Ki67. The abundant vasculature of the lamina propria was observed on slides and the CD34 antibodies labeled endothelial tip cells in various stages of the endothelial sprouts. Ki67 identified positive endothelial cells, confirming the proliferative status of the microvascular bed. According to the results, the in situ sprouting angiogenesis is driven by tip cells in the oral mucosa of the edentulous ridge and these cells can be targeted by various therapies, as required by the local pathologic or therapeutic conditions.

Small-diameter dental implants: An adjunct for retention, stability, and comfort for the edentulous patient

Directory of Open Access Journals (Sweden)

Antonio Scarano

2012-10-01

Full Text Available Aim: Studies have shown that mandibular implant overdentures significantly increase satisfaction and quality of life of edentulous elders. Improved chewing ability appears to have a positive impact on nutritional state. Materials and methods: Forty edentulous subjects received four permucosal mini-implants for overdentures in the interforamina region of the mandible. Almost all participants were still satisfied with their overdentures. Participant satisfaction concerning retention and stability of the mandibular overdenture was assessed. A micro invasive technique was adopted, without open flap and performed in one chirurgical step; this technique can be used also in the so-called “highrisk” patients (anticoagulant terapy, diabetes, etc. Results and conclusion: Results and conclusion The results suggest that a mandibular overdenture retained by 4 mini-implants may be the best treatment strategy for edentulous people with atrophic ridges. The use of mini-implants is in many cases a good clinical alternative to the use of larger diameter implants, in that they enable to reduce surgical time, bleeding, postoperative discomfort and healing time.

Jaw morphology and ontogeny in five species of Ophryothrocha

DEFF Research Database (Denmark)

Macnaughton, Martin Oliver; Worsaae, Katrine; Eibye-Jacobsen, Danny

2010-01-01

Detailed scanning electron microscopy of jaws within the genus Ophryotrocha (Dorvilleidae, Annelida) was performed on 871 jaw parts. The investigations resulted in new understandings of the ontogeny and jaw morphology and have systematic implications for the family. Five species in the genus (Oph...

Radiologic study of osteomyelitis of the jaw

International Nuclear Information System (INIS)

Lee, Young Ho; Ahn, Hyung Kyu

1980-01-01

The author studied age and sex distribution, etiology, affected site and several radiographic features of osteomyelitis of the jaw. And radiologic classification of osteomyelitis was also done. The material consisted of 118 males and 96 females examined and/or treated under the diagnosis of osteomyelitis during past 11 years (1970-1980.6) in SNUDH. The obtained results were as followings. 1. The incidence is the highest in teen ages (22.9%) and the lowest in seventies. (2.8%). 2. 199 cases were found in lower jaw, and 15 cases in upper jaw. 30.8% of all cases were located at the posterior portion of mandibular body comprising alveolar region. 3. Radiographic examination of osteolytic lesion revealed that 21.5% of all patients had periapical and alveolar bone rarefaction combined with osteoporotic changes were present at the same time. 4. Sclerotic lesions were seen in 62.2% of all patients and 21.5% of sclerotic lesion were diffuse or homogenous type. 5. Based on the radiologic study, classification of the osteomyelitis of the jaw was made. Localized osteolytic type was the highest in incidence (38.8%) and localized sclerotic type was the lowest (7.0%).

Implant-assisted removable partial dentures: practical considerations.

Science.gov (United States)

Omura, Aaron J; Latthe, Vaibhav; Marin, Mark M; Cagna, David R

2016-01-01

At the heart of prosthodontic treatment planning must be a sound understanding of the quality and reliability of the prosthodontic foundation. Implant prosthodontics relies almost entirely on the biological and mechanical properties of an osseous foundation. Initiation of therapy in the absence of a healthy and stable prosthodontic foundation risks unintended and suboptimal treatment outcomes. For conventional removable partial denture (RPD) therapy, consideration must be given to interactions between the soft and hard tissues available to support and stabilize planned prostheses. The strategic addition of implants to the partially edentulous foundation can improve the support, comfort, and esthetics of an RPD, resulting in elevated patient satisfaction and greater therapeutic success. This article discusses aspects of diagnosis, treatment planning, clinical management, laboratory execution, and maintenance that must be considered in order to obtain optimal results with implant-assisted RPDs.

Lip line changes in Class III facial asymmetry patients after orthodontic camouflage treatment, one-jaw surgery, and two-jaw surgery: A preliminary study.

Science.gov (United States)

Lee, Gung-Chol; Yoo, Jo-Kwang; Kim, Seong-Hun; Moon, Cheol-Hyun

2017-03-01

To evaluate the effects of orthodontic camouflage treatment (OCT), one-jaw surgery, and two-jaw surgery on the correction of lip line cant (LLC) and to examine factors affecting the correction of LLC in Class III craniofacial asymmetry patients. A sample of 30 Class III craniofacial asymmetry patients was divided into OCT (n = 10), one-jaw surgery (n = 10), and two-jaw surgery (n = 10) groups such that the pretreatment LLC was similar in each group. Pretreatment and posttreatment cone-beam computed tomography scans were used to measure dental and skeletal parameters and LLC. Pretreatment and posttreatment measurements were compared within groups and between groups. Pearson's correlation tests and multiple regression analyses were performed to investigate factors affecting the amount and rate of LLC correction. The average LLC correction was 1.00° in the one-jaw surgery group, and in the two-jaw surgery group, it was 1.71°. In the OCT group it was -0.04°, which differed statistically significantly from the LLC correction in the other two groups. The amount and rate of LLC correction could be explained by settling of skeletal discrepancies or LLC at pretreatment with goodness of fit percentages of approximately 82% and 41%, respectively. Orthognathic surgery resulted in significant correction of LLC in Class III craniofacial asymmetry patients, while OCT did not.

Jaw tremor as a physiological biomarker of bruxism.

Science.gov (United States)

Laine, C M; Yavuz, Ş U; D'Amico, J M; Gorassini, M A; Türker, K S; Farina, D

2015-09-01

To determine if sleep bruxism is associated with abnormal physiological tremor of the jaw during a visually-guided bite force control task. Healthy participants and patients with sleep bruxism were given visual feedback of their bite force and asked to trace triangular target trajectories (duration=20s, peak force bruxism have abnormal jaw tremor when engaged in a visually-guided bite force task. Measurement of jaw tremor may aid in the detection/evaluation of bruxism. In light of previous literature, our results also suggest that bruxism is marked by abnormal or mishandled peripheral feedback from the teeth. Copyright © 2015. Published by Elsevier Ireland Ltd.

Dentoskeletal Overjet Measurements of Iraqi Adult Sample with Different Skeletal Jaw Relationship

Directory of Open Access Journals (Sweden)

Shahbaa A Mohammed

2017-11-01

Full Text Available Background: Many attempts were done to develop a method that actually reflects the sagittal jaw discrepancies without depending on cranial landmarks or dental occlusion. This study aimed to use one of these methods (dentoskeletal overjet for assessing the sagittal jaw relationships of Iraqi adult sample with different skeletal jaw relationship. Materials and method: The sample consisted of 90 digital true lateral cephalometric radiographs of Iraqi individuals with no previous orthodontic treatment. Cephalometric analysis of skeletal sagittal jaw relationship -ANB angle, beta angle and Wits appraisal- will perform for everyone to divide the sample into three groups (skeletal class I, II, III for which the dentoskeletal overjet will be measured. All cephalometric measurements will be done using AutoCAD. Results: Descriptive statistics of all variables with different skeletal jaw relationship showed that mean values of dentoskeletal overjet were (1.15, 3.91 and –2.01 mm for skeletal class I, class II and class III jaw relationship respectively. Accurate reproducibility of dentoskeletal overjet in assessment of jaw skeletal relationship showed that the lowest value was for assessment of skeletal class III jaw relationship (73% and the value for assessment of both skeletal class I and class II was higher (93%. Conclusions: Dentoskeletal overjet could be utilized in accurate representation of skeletal jaw relationship.

Validity of linear measurements of the jaws using ultralow-dose MDCT and the iterative techniques of ASIR and MBIR.

Science.gov (United States)

Al-Ekrish, Asma'a A; Al-Shawaf, Reema; Schullian, Peter; Al-Sadhan, Ra'ed; Hörmann, Romed; Widmann, Gerlig

2016-10-01

To assess the comparability of linear measurements of dental implant sites recorded from multidetector computed tomography (MDCT) images obtained using standard-dose filtered backprojection (FBP) technique with those from various ultralow doses combined with FBP, adaptive statistical iterative reconstruction (ASIR), and model-based iterative reconstruction (MBIR) techniques. The results of the study may contribute to MDCT dose optimization for dental implant site imaging. MDCT scans of two cadavers were acquired using a standard reference protocol and four ultralow-dose test protocols (TP). The volume CT dose index of the different dose protocols ranged from a maximum of 30.48-36.71 mGy to a minimum of 0.44-0.53 mGy. All scans were reconstructed using FBP, ASIR-50, ASIR-100, and MBIR, and either a bone or standard reconstruction kernel. Linear measurements were recorded from standardized images of the jaws by two examiners. Intra- and inter-examiner reliability of the measurements were analyzed using Cronbach's alpha and inter-item correlation. Agreement between the measurements obtained with the reference-dose/FBP protocol and each of the test protocols was determined with Bland-Altman plots and linear regression. Statistical significance was set at a P-value of 0.05. No systematic variation was found between the linear measurements obtained with the reference protocol and the other imaging protocols. The only exceptions were TP3/ASIR-50 (bone kernel) and TP4/ASIR-100 (bone and standard kernels). The mean measurement differences between these three protocols and the reference protocol were within ±0.1 mm, with the 95 % confidence interval limits being within the range of ±1.15 mm. A nearly 97.5 % reduction in dose did not significantly affect the height and width measurements of edentulous jaws regardless of the reconstruction algorithm used.

SU-F-E-19: A Novel Method for TrueBeam Jaw Calibration

Energy Technology Data Exchange (ETDEWEB)

Corns, R; Zhao, Y; Huang, V [Fraser Valley Cancer Centre - BC Cancer Agency, Surrey, BC (United Kingdom)

2016-06-15

Purpose: A simple jaw calibration method is proposed for Varian TrueBeam using an EPID-Encoder combination that gives accurate fields sizes and a homogeneous junction dose. This benefits clinical applications such as mono-isocentric half-beam block breast cancer or head and neck cancer treatment with junction/field matching. Methods: We use EPID imager with pixel size 0.392 mm × 0.392 mm to determine the radiation jaw position as measured from radio-opaque markers aligned with the crosshair. We acquire two images with different symmetric field sizes and record each individual jaw encoder values. A linear relationship between each jaw’s position and its encoder value is established, from which we predict the encoder values that produce the jaw positions required by TrueBeam’s calibration procedure. During TrueBeam’s jaw calibration procedure, we move the jaw with the pendant to set the jaw into position using the predicted encoder value. The overall accuracy is under 0.1 mm. Results: Our in-house software analyses images and provides sub-pixel accuracy to determine field centre and radiation edges (50% dose of the profile). We verified the TrueBeam encoder provides a reliable linear relationship for each individual jaw position (R{sup 2}>0.9999) from which the encoder values necessary to set jaw calibration points (1 cm and 19 cm) are predicted. Junction matching dose inhomogeneities were improved from >±20% to <±6% using this new calibration protocol. However, one technical challenge exists for junction matching, if the collimator walkout is large. Conclusion: Our new TrueBeam jaw calibration method can systematically calibrate the jaws to crosshair within sub-pixel accuracy and provides both good junction doses and field sizes. This method does not compensate for a larger collimator walkout, but can be used as the underlying foundation for addressing the walkout issue.

Changes in the edentulous maxilla in persons wearing implant-retained mandibular overdentures

NARCIS (Netherlands)

Narhi, TO; Geertman, ME; Hevinga, M; Abdo, H; Kalk, W

Statement of problem. It has been suggested that risk for severe resorption in the anterior maxilla is increased in persons wearing mandibular implant-retained overdentures. However, little information is available about the changes in the edentulous maxilla after mandibular implant treatment.

Restoration of Oral Function for Adult Edentulous Patients with Ectodermal Dysplasia: A Prospective Preliminary Clinical Study.

Science.gov (United States)

Wu, Yiqun; Wang, Xu Dong; Wang, Feng; Huang, Wei; Zhang, Zhiyong; Zhang, Zhiyuan; Kaigler, Darnell; Zou, Duohong

2015-10-01

Therapy with zygomatic implants (ZIs) or conventional implants (CIs) has proven to be an effective method to restore oral function for systemically healthy patients. However, it is still a major challenge to fully restore oral function to edentulous adult patients with ectodermal dysplasia (ED). The aim of this study was to determine an effective treatment protocol for restoring oral function using ZIs and CIs to edentulous adult ED patients. Ten edentulous adult ED patients were treated in this study. The treatment protocol involved the following: (1) bone augmentation in the region of the anterior teeth; (2) placement of two ZIs and four CIs in the maxilla, and four CIs in the mandible; (3) fabrication of dental prosthesis; and (4) psychological and oral education. Following treatment of these patients, implant success rates, biological complications, patient satisfaction, and psychological changes were recorded. Although there was evidence of bone graft resorption in the maxilla, bone augmentation of the mandible was successful in all patients. Nine CIs in the maxilla failed and were removed. All ZIs were successful, and the CIs success rates were 77.50% in the maxilla and 100% in the mandible, with a mean of 88.75%. The mean peri-implant bone resorption for the CIs ranged from 1.3 ± 0.4 mm to 1.8 ± 0.6 mm, and four cases exhibited gingival hyperplasia in the maxilla and mandible. One hundred percent of the patients were satisfied with the restoration of their oral function, and >50% of the patients exhibited enhanced self-confidence and self-esteem. This study demonstrates that oral function can be restored in edentulous adult ED patients using a comprehensive and systematic treatment protocol involving psychological and oral education, bone augmentation, implant placement, and denture fabrication. Despite these positive outcomes, bone augmentation remains challenging in the anterior region of the maxilla for edentulous adult ED patients. © 2015

Imaging technique for the complete edentulous patient treated conventionally or with mini implant overdenture

Science.gov (United States)

Meleşcanu Imre, M; Preoteasa, E; Țâncu, AM; Preoteasa, CT

2013-01-01

Rationale. The imaging methods are more and more used in the clinical process of modern dentistry. Once the implant based treatment alternatives are nowadays seen as being the standard of care in edentulous patients, these techniques must be integrated in the complete denture treatment. Aim. The study presents some evaluation techniques for the edentulous patient treated by conventional dentures or mini dental implants (mini SKY Bredent) overdentures, using the profile teleradiography. These offer data useful for an optimal positioning of the artificial teeth and the mini dental implants, favoring to obtain an esthetic and functional treatment outcome. We proposed also a method to conceive a simple surgical guide that allows the prosthetically driven implants placement. Material and method. Clinical case reports were made, highlighting the importance of cephalometric evaluation on lateral teleradiographs in complete edentulous patients. A clinical case that gradually reports the surgical guide preparation (Bredent silicon radio opaque), in order to place the mini dental implants in the best prosthetic and anatomic conditions, was presented. Conclusions. The profile teleradiograph is a useful tool for the practitioner. It allows establishing the optimal site for implant placement, in a good relation with the overdenture. The conventional denture can be easily and relatively costless transformed in a surgical guide used during implant placement. PMID:23599828

Age, period, and cohort analysis of regular dental care behavior and edentulism: A marginal approach

Science.gov (United States)

2011-01-01

Background To analyze the regular dental care behavior and prevalence of edentulism in adult Danes, reported in sequential cross-sectional oral health surveys by the application of a marginal approach to consider the possible clustering effect of birth cohorts. Methods Data from four sequential cross-sectional surveys of non-institutionalized Danes conducted from 1975-2005 comprising 4330 respondents aged 15+ years in 9 birth cohorts were analyzed. The key study variables were seeking dental care on an annual basis (ADC) and edentulism. For the analysis of ADC, survey year, age, gender, socio-economic status (SES) group, denture-wearing, and school dental care (SDC) during childhood were considered. For the analysis of edentulism, only respondents aged 35+ years were included. Survey year, age, gender, SES group, ADC, and SDC during childhood were considered as the independent factors. To take into account the clustering effect of birth cohorts, marginal logistic regressions with an independent correlation structure in generalized estimating equations (GEE) were carried out, with PROC GENMOD in SAS software. Results The overall proportion of people seeking ADC increased from 58.8% in 1975 to 86.7% in 2005, while for respondents aged 35 years or older, the overall prevalence of edentulism (35+ years) decreased from 36.4% in 1975 to 5.0% in 2005. Females, respondents in the higher SES group, in more recent survey years, with no denture, and receiving SDC in all grades during childhood were associated with higher probability of seeking ADC regularly (P dental health policy was demonstrated by a continued increase of regular dental visiting habits and tooth retention in adults because school dental care was provided to Danes in their childhood. PMID:21410991

ITI implants with overdentures: a prevention of bone loss in edentulous mandibles?

DEFF Research Database (Denmark)

von Wowern, N; Harder, F; Hjørting-Hansen, E

1990-01-01

Changes in the bone mineral content (BMC) of edentulous mandibles with osseointegrated ITI implants supporting overdentures were measured in vivo by dual-photon absorptiometry. The BMC measurements were performed 3 weeks postoperatively and at the 2-year follow-up visit. Measurements were made...

Mastication improvement after partial implant-supported prosthesis use.

Science.gov (United States)

Gonçalves, T M S V; Campos, C H; Gonçalves, G M; de Moraes, M; Rodrigues Garcia, R C M

2013-12-01

Partially edentulous patients may be rehabilitated by the placement of removable dental prostheses, implant-supported removable dental prostheses, or partial implant fixed dental prostheses. However, it is unclear the impact of each prosthesis type over the masticatory aspects, which represents the objective of this paired clinical trial. Twelve patients sequentially received and used each of these 3 prosthesis types for 2 months, after which maximum bite force was assessed by a strain sensor and food comminution index was determined with the sieving method. Masseter and temporal muscle thicknesses during rest and maximal clenching were also evaluated by ultrasonography. Each maxillary arch received a new complete denture that was used throughout the study. Data were analyzed by analysis of variance for repeated measures, followed by the Tukey test (p mastication, and the magnitude of this effect was related to prosthesis type.

[Evaluation of cermet fillings in abutment teeth in removable partial prostheses].

Science.gov (United States)

Saulic, S; Tihacek-Sojic, Lj

2001-01-01

The aim of the study was to describe the clinical process of setting the purpose filling on abutment teeth, after finishing the removable partial dentures. The aim was also to investigate the use of cermet glass-ionomer cement for the purpose filling in the abutment teeth for removable partial dentures, as well as to investigate the surface of the purpose filling. For the clinical evaluation of purpose filling slightly modified criteria according to Ryg's were used in 20 patients with different type of edentulousness. Changes occurring on the surface of purpose filling have been experimentally established by the method of scanning electron microscopy on the half-grown third molars in seven patients. It could be concluded that cement glass-ionomer was not the appropriate material for the purpose fillings in abutment teeth for removable partial dentures.

Orthodontic treatment-induced temporal alteration of jaw-opening reflex excitability.

Science.gov (United States)

Sasaki, Au; Hasegawa, Naoya; Adachi, Kazunori; Sakagami, Hiroshi; Suda, Naoto

2017-10-01

The impairment of orofacial motor function during orthodontic treatment needs to be addressed, because most orthodontic patients experience pain and motor excitability would be affected by pain. In the present study, the temporal alteration of the jaw-opening reflex excitability was investigated to determine if orthodontic treatment affects orofacial motor function. The excitability of jaw-opening reflex evoked by electrical stimulation on the gingiva and recorded bilaterally in the anterior digastric muscles was evaluated at 1 (D1), 3 (D3), and 7 days (D7) after orthodontic force application to the teeth of right side; morphological features (e.g., osteoclast genesis and tooth movement) were also evaluated. To clarify the underlying mechanism of orthodontic treatment-induced alteration of orofacial motor excitability, analgesics were administrated for 1 day. At D1 and D3, orthodontic treatment significantly decreased the threshold for inducing the jaw-opening reflex but significantly increased the threshold at D7. Other parameters of the jaw-opening reflex were also evaluated (e.g., latency, duration and area under the curve of anterior digastric muscles activity), and only the latency of the D1 group was significantly different from that of the other groups. Temporal alteration of the jaw-opening reflex excitability was significantly correlated with changes in morphological features. Aspirin (300 mg·kg -1 ·day -1 ) significantly increased the threshold for inducing the jaw-opening reflex, whereas a lower dose (75-150 mg·kg -1 ·day -1 ) of aspirin or acetaminophen (300 mg·kg -1 ·day -1 ) failed to alter the jaw-opening reflex excitability. These results suggest that an increase of the jaw-opening reflex excitability can be induced acutely by orthodontic treatment, possibly through the cyclooxygenase activation. NEW & NOTEWORTHY It is well known that motor function is affected by pain, but the effect of orthodontic treatment-related pain on the trigeminal

Effects of a denture adhesive in edentulous patients after maxillectomy.

Science.gov (United States)

Sumita, Yuka I; Otomaru, Takafumi; Taniguchi, Hisashi

2012-06-01

The objective of this study is to evaluate the usefulness of a denture adhesive in edentulous patients after maxillectomy. Maxillectomy patients suffer from functional impairments. Denture adhesives (DAs) are the solution in such patients. However, little is known about DAs in maxillectomy patients. Eight edentulous patients who had undergone maxillectomy were included and divided into three groups. Group 1 (half ≤ remaining residual maxilla), Group 2 (quarter < remaining residual maxilla < half) and Group 3 (remaining residual maxilla ≤ quarter). They were evaluated by a speech intelligibility test and a mixing ability test, respectively. A cream-type DA called New Poligrip(®) (GlaxoSmithKline, Tokyo, Japan) was used. Applying the DA, speech intelligibility showed a higher score than the data without DA. The effects of using a DA depend on the amount of the remaining residual maxilla. Our study showed that if the remaining residual maxilla is less than a quarter (Group 3), it is difficult to have confidence in the effectiveness of the DA to improve masticatory function. On the other hand, the use a DA showed improved speech intelligibility test values in all groups. © 2011 The Gerodontology Society and John Wiley & Sons A/S.

Prefabricated light-polymerizing plastic pattern for partial denture framework

Directory of Open Access Journals (Sweden)

Atsushi Takaichi

2011-01-01

Full Text Available Our aim is to report an application of a prefabricated light-polymerizing plastic pattern to construction of removable partial denture framework without the use of a refractory cast. A plastic pattern for the lingual bar was adapted on the master cast of a mandibular Kennedy class I partially edentulous patient. The pattern was polymerized in a light chamber. Cobalt-chromium wires were employed to minimize the potential distortion of the plastic framework. The framework was carefully removed from the master cast and invested with phosphate-bonded investment for the subsequent casting procedures. A retentive clasp was constructed using 19-gauge wrought wire and was welded to the framework by means of laser welding machine. An excellent fit of the framework in the patient′s mouth was observed in the try-in and the insertion of the denture. The result suggests that this method minimizes laboratory cost and time for partial denture construction.

Independently evolved upper jaw protrusion mechanisms show convergent hydrodynamic function in teleost fishes.

Science.gov (United States)

Staab, Katie Lynn; Holzman, Roi; Hernandez, L Patricia; Wainwright, Peter C

2012-05-01

A protrusible upper jaw has independently evolved multiple times within teleosts and has been implicated in the success of two groups in particular: Acanthomorpha and Cypriniformes. We use digital particle image velocimetry (DPIV) to compare suction feeding flow dynamics in a representative of each of these clades: goldfish and bluegill. Using DPIV, we contrast the spatial pattern of flow, the temporal relationship between flow and head kinematics, and the contribution of jaw protrusion to the forces exerted on prey. As expected, the spatial patterns of flow were similar in the two species. However, goldfish were slower to reach maximal kinematic excursions, and were more flexible in the relative timing of jaw protrusion, other jaw movements and suction flows. Goldfish were also able to sustain flow speeds for a prolonged period of time as compared with bluegill, in part because goldfish generate lower peak flow speeds. In both species, jaw protrusion increased the force exerted on the prey. However, slower jaw protrusion in goldfish resulted in less augmentation of suction forces. This difference in force exerted on prey corresponds with differences in trophic niches and feeding behavior of the two species. The bluegill uses powerful suction to capture insect larvae whereas the goldfish uses winnowing to sort through detritus and sediment. The kinethmoid of goldfish may permit jaw protrusion that is independent of lower jaw movement, which could explain the ability of goldfish to decouple suction flows (due to buccal expansion) from upper jaw protrusion. Nevertheless, our results show that jaw protrusion allows both species to augment the force exerted on prey, suggesting that this is a fundamental benefit of jaw protrusion to suction feeders.

Restoration of unfavorably positioned implants for a partially endentulous patient by using an overdenture retained with a milled bar and attachments: a clinical report.

Science.gov (United States)

Asvanund, Chanavut; Morgano, Steven M

2004-01-01

The restorative dentist may encounter patients with previously placed misaligned implants that are well integrated. Often, these patients have deficient alveolar ridge contour further complicating treatment options. This clinical report describes a treatment approach for a partially edentulous patient with unfavorably positioned implants that incorporated: (1) an implant-supported milled bar with a removable, metal-acrylic resin, partial overdenture, (2) implant-supported single crowns, and (3) crowns retained by natural teeth.

Narrow- (3.0 mm) Versus Standard-Diameter (4.0 and 4.5 mm) Implants for Splinted Partial Fixed Restoration of Posterior Mandibular and Maxillary Jaws: A 5-Year Retrospective Cohort Study.

Science.gov (United States)

Pieri, Francesco; Forlivesi, Caterina; Caselli, Ernesto; Corinaldesi, Giuseppe

2017-04-01

Evidence concerning predictability of narrow-diameter implants (NDIs) (3.0 mm) and standard-diameter implants (SDIs) (4.0 to 4.5 mm) supporting fixed partial dentures (FPDs) in posterior mandibular and maxillary jaws. All patients treated with at least two adjacent NDIs or SDIs according to available bone thickness and with a minimum follow-up of 5 years after placement were invited to undergo a clinical and radiologic examination. Outcome measures were implant and FPD failures, biologic and prosthetic complications, and marginal bone loss. A total of 107 out of 127 patients attended the examination: 49 (113 implants) of the NDI group, and 58 (126 implants) of the SDI group. Two NDIs failed in one patient versus four SDIs in four patients (P = 0.37). One FPD failed in the NDI group versus two FPDs in the SDI group (P >0.99). Nine biologic complications occurred in the NDI group and twelve in the SDI group (P = 0.81). Twelve prosthetic complications occurred in the NDI group and only two in the SDI group (P = 0.001). Peri-implant marginal bone loss at 5 years was 0.95 ± 0.84 mm for the NDI group and 1.2 ± 0.86 mm for the SDI group (P = 0.06). Five-year data indicate that FPD treatment in posterior mandibular and maxillary jaws with NDIs was as reliable as with SDIs, although NDIs showed a higher risk of prosthetic complications.

Treatment of edentulism: optimizing outcomes with tissue management and impression techniques.

Science.gov (United States)

Salinas, Thomas J

2009-02-01

Significant numbers of patients throughout the world seek treatment for edentulism. The trend toward tissue-integrated prostheses has been a monumental step in restoring edentulous patients to function; however, this treatment can be out of reach for those who fail to qualify or those who do not have sufficient resources to afford it. In these cases, conventional dentures remain an important primary course of treatment. Attention to detail when diagnosing, treatment planning, and performing treatment for these patients is still a prime consideration for the best possible outcome. In particular, many experienced denture wearers are afflicted with chronically inflamed denture-bearing mucosa. Clinicians must recognize the need for tissue conditioning, choices of impression materials, and accepted fabrication techniques that can have favorable outcomes when matched with patients who are philosophical and realistic in their expectations. The purpose of this article is to review impression philosophies, associated materials, and methods of tissue conditioning. Retention and stability of the denture bases can be augmented by the routine use of denture adhesive, and indications for use of denture adhesive will be discussed.

Digital Workflow for Computer-Guided Implant Surgery in Edentulous Patients: A Case Report.

Science.gov (United States)

Oh, Ji-Hyeon; An, Xueyin; Jeong, Seung-Mi; Choi, Byung-Ho

2017-12-01

The purpose of this article was to describe a fully digital workflow used to perform computer-guided flapless implant placement in an edentulous patient without the use of conventional impressions, models, or a radiographic guide. Digital data for the workflow were acquired using an intraoral scanner and cone-beam computed tomography (CBCT). The image fusion of the intraoral scan data and CBCT data was performed by matching resin markers placed in the patient's mouth. The definitive digital data were used to design a prosthetically driven implant position, surgical template, and computer-aided design and computer-aided manufacturing fabricated fixed dental prosthesis. The authors believe this is the first published case describing such a technique in computer-guided flapless implant surgery for edentulous patients. Copyright © 2017 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

Pain and Disability in the Jaw and Neck Region following Whiplash Trauma.

Science.gov (United States)

Häggman-Henrikson, B; Lampa, E; Marklund, S; Wänman, A

2016-09-01

The relationship between whiplash trauma and chronic orofacial pain is unclear, especially with regard to the time elapsed from trauma to development of orofacial pain. The aim was to analyze prevalence of jaw pain and disability, as well as the relationship between pain and disability in the jaw and neck regions in the early nonchronic stage after whiplash trauma. In this case-control study, 70 individuals (40 women, 30 men, mean age 35.5 y) who visited an emergency department with neck pain following a car accident were examined within 3 wk of trauma (group 1) and compared with 70 individuals (42 women, 28 men, mean age 33.8 y), who declined to attend a clinical examination but agreed to fill in questionnaires (group 2). The 2 case groups were compared with a matched control group of 70 individuals (42 women, 28 men, mean age 37.6 y) without a history of neck trauma. All participants completed questionnaires regarding jaw pain and dysfunction, rating pain intensity in jaw and neck regions on the Numerical Rating Scale, the Neck Disability Index, and Jaw Disability Checklist. Compared with controls, individuals with a recent whiplash trauma reported more jaw pain and dysfunction. Furthermore, there was a moderate positive correlation between jaw and neck pain ratings for group 1 (r = 0.61, P whiplash trauma report more jaw pain and disability compared with controls without a history of neck trauma. Furthermore, the correlation between jaw and neck pain intensity implies that intensity of neck pain in the acute stage after whiplash trauma might be a possible risk factor also for development of chronic orofacial pain. © International & American Associations for Dental Research 2016.

Eosinophilic Granuloma in Jaw Bone

African Journals Online (AJOL)

GB

CONCLUSION: EG should be considered as a differential diagnosis whenever there is a bony destructive lesion involving alveolar bone of the Jaws. Early diagnosis and surgical ... radiographic examination, these lesions should be biopsied.

Florid osseous dysplasia of the jaws

International Nuclear Information System (INIS)

Cho, Su Beom; Koh, Kwang Joon

1995-01-01

Few cases of florid osseous dysplasia has been described as a condition that characteristically affects the jaws. It usually manifests as multiple radiopaque masses distributed throughout the jaws. Confusion exists about the relationship of florid osseous dysplasia, gigantiform cementoma, chronic sclerosing osteomyelitis, sclerosing osteitis or multiple enostosis. Authors experienced a case of florid osseous dysplasia of the jaws in 52-year-old female on the basis of clinical, radiographic and histopathologic findings. The characteristic features are as follows: 1. In clinical examination, there was no clinical sign and symptoms except extrated area. And there was no facial asymmetry. 2. Radiograms show round or lobular dense radiopaque masses surrounded by radiolucent bands in lower molar teeth area bilaterally. And slight increased radiopacities in maxillary molar teeth area bilaterllay. There was no expansion or thinning of buccal and lingual cortical bones. There is no displacement or resorption of involved teeth. In right side of mandible, mandibular canal is displaced inferiorly due to mass. 3. Photomicrograms show densely mineralized sclerotic acellular masses with empty lacunae. Pattern is suggestive of cementum, although it could be considered sclerotic bone. In the periphery, lesion consisting of moderately cellular fibrous tissue in calcified products are deposited.

Predictable Technique to Register Retruded Contact Position (RCP) Using a Disposable Jaw Relation Recording Device.

Science.gov (United States)

Daher, Tony; Lobel, William A; Massad, Joseph; Ahuja, Swati; Danilov, Zarko Jack

2015-05-01

The dental literature presents various definitions and techniques to describe and register centric relation (CR) or centric occlusion (CO). Briefly reviewing the literature in relation to CR, this article proposes the use of the term retruded contact position (RCP), clinically defined as retruded, unstrained, repeatable position and where the mandibular movements start when a Gothic arch tracing is used. With this clinical definition, a technique can be easily selected that meets all the requirements of such position. The article discusses the use of a jaw recorder that is an intraorally graphic recording device that results in a tracing of mandibular movements in one plane, with the apex of the tracing indicating the retruded, unstrained, and repeatable relationship. The intersection of the arcs produced by the right and left working movement form the apex of the Gothic arch tracing. Several clinical situations using the jaw recorder are described. Clinicians can now quickly and accurately record RCP, balance complete, partial, or implant dentures, and orthopedically reposition the mandible. The technique achieves highly reliable and reproducible results.

Surgical treatment of jaw osteonecrosis in "Krokodil" drug addicted patients.

Science.gov (United States)

Poghosyan, Yuri M; Hakobyan, Koryun A; Poghosyan, Anna Yu; Avetisyan, Eduard K

2014-12-01

Retrospective study of jaw osteonecrosis treatment in patients using the "Krokodil" drug from 2009 to 2013. On the territory of the former USSR countries there is widespread use of a self-produced drug called "Krokodil". Codeine containing analgesics ("Sedalgin", "Pentalgin" etc), red phosphorus (from match boxes) and other easily acquired chemical components are used for synthesis of this drug, which used intravenously. Jaw osteonecrosis develops as a complication in patients who use "Krokodil". The main feature of this disease is jawbone exposure in the oral cavity. Surgery is the main method for the treatment of jaw osteonecrosis in patients using "Krokodil". 40 "Krokodil" drug addict patients with jaw osteonecrosis were treated. Involvement of maxilla was found in 11 patients (27.5%), mandible in 21 (52.5%), both jaws in 8 (20%) patients. 35 Lesions were found in 29 mandibles and 21 lesions in 19 maxillas. Main factors of treatment success are: cessation of "Krokodil" use in the pre- (minimum 1 month) and postoperative period and osteonecrosis area resection of a minimum of 0.5 cm beyond the visible borders of osteonecrosis towards the healthy tissues. Surgery was not delayed until sequestrum formation. In the mandible marginal or segmental resection (with or without TMJ exarticulation) was performed. After surgery recurrence of disease was seen in 8 (23%) cases in the mandible, with no cases of recurrence in the maxilla. According to our experience in this case series, surgery is the main method for the treatment of jaw osteonecrosis in patients using "Krokodil". Cessation of drug use and jaw resection minimize the rate of recurrences in such patients. Copyright © 2014 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

Expression of Msx-1 is suppressed in bisphosphonate associated osteonecrosis related jaw tissue-etiopathology considerations respecting jaw developmental biology-related unique features.

Science.gov (United States)

Wehrhan, Falk; Hyckel, Peter; Ries, Jutta; Stockmann, Phillip; Nkenke, Emeka; Schlegel, Karl A; Neukam, Friedrich W; Amann, Kerstin

2010-10-13

Bone-destructive disease treatments include bisphosphonates and antibodies against the osteoclast differentiator, RANKL (aRANKL); however, osteonecrosis of the jaw (ONJ) is a frequent side-effect. Current models fail to explain the restriction of bisphosphonate (BP)-related and denosumab (anti-RANKL antibody)-related ONJ to jaws. Msx-1 is exclusively expressed in craniofacial structures and pivotal to cranial neural crest (CNC)-derived periodontal tissue remodeling. We hypothesised that Msx-1 expression might be impaired in bisphosphonate-related ONJ. The study aim was to elucidate Msx-1 and RANKL-associated signal transduction (BMP-2/4, RANKL) in ONJ-altered and healthy periodontal tissue. Twenty ONJ and twenty non-BP exposed periodontal samples were processed for RT-PCR and immunohistochemistry. An automated staining-based alkaline phosphatase-anti-alkaline phosphatase method was used to measure the stained cells:total cell-number ratio (labelling index, Bonferroni adjustment). Real-time RT-PCR was performed on ONJ-affected and healthy jaw periodontal samples (n = 20 each) to quantitatively compare Msx-1, BMP-2, RANKL, and GAPDH mRNA levels. Semi-quantitative assessment of the ratio of stained cells showed decreased Msx-1 and RANKL and increased BMP-2/4 (all p Msx-1 (p Msx-1 suppression in ONJ-adjacent periodontal tissue suggested a bisphosphonate-related impairment in cellular differentiation that occurred exclusively jaw remodelling. Further research on developmental biology-related unique features of jaw bone structures will help to elucidate pathologies restricted to maxillofacial tissue.

Maxillary rehabilitation using fixed and removable partial dentures with attachments: a clinical report.

Science.gov (United States)

dos Santos Nunes Reis, José Maurício; da Cruz Perez, Luciano Elias; Alfenas, Bruna Fernandes Moreira; de Oliveira Abi-Rached, Filipe; Filho, João Neudenir Arioli

2014-01-01

Despite requiring dental crown preparation and possible root canal treatment, besides the difficulty of clinical and laboratory repairs, and financial burden, the association between fixed (FPD) and removable partial dentures (RPD) by means of attachments is an important alternative for oral rehabilitation, particularly when the use of dental implants and FPDs is limited or not indicated. Among the advantages of attachment-retained RPDs are the improvements in esthetics and biomechanics, as well as correction of the buccal arrangement of anterior teeth in Kennedy Class III partially edentulous arches. This article describes the treatment sequence and technique for the use of attachments in therapy combining FPD/RPD. © 2013 by the American College of Prosthodontists.

Masticatory jaw movement of Exaeretodon argentinus (Therapsida: Cynodontia inferred from its dental microwear.

Directory of Open Access Journals (Sweden)

Tai Kubo

Full Text Available Dental microwear of four postcanine teeth of Exaeretodon argentinus was analyzed using both two dimensional (2D and three dimensional (3D methods to infer their masticatory jaw movements. Results of both methods were congruent, showing that linear microwear features (scratches were well aligned and mostly directed to the antero-posterior direction in all four teeth examined. These findings support the palinal masticatory jaw movement, which was inferred in previous studies based on the observation of gross morphology of wear facets. In contrast, the lack of detection of lateral scratches confirmed the absence of the lateral jaw movement that was also proposed by a previous study. Considering previous microwear studies on cynodonts, palinal jaw movements observed in Exaeretodon evolved within cynognathian cynodonts from the fully orthal jaw movement of its basal member. Although there are currently only three studies of dental microwear of non-mammalian cynodonts including the present study, microwear analysis is a useful tool for the reconstruction of masticatory jaw movement and its future application to various cynodonts will shed light on the evolutionary process of jaw movement towards the mammalian condition in more detail.

Kinematic analysis of jaw function in children following traumatic brain injury.

Science.gov (United States)

Loh, E W L; Goozée, J V; Murdoch, B E

2005-07-01

To investigate jaw movements in children following traumatic brain injury (TBI) during speech using electromagnetic articulography (EMA). Jaw movements of two non-dysarthric children (aged 12.75 and 13.08 years) who had sustained a TBI were recorded using the AG-100 EMA system (Carstens Medizineletronik) during word-initial consonant productions. Mean quantitative kinematic parameters and coefficient of variation (variability) values were calculated and individually compared to the mean values obtained by a group of six control children (mean age 12.57 years, SD 1.52). The two children with TBI exhibited word-initial consonant jaw movement durations that were comparable to the control children, with sub-clinical reductions in speed being offset by reduced distances. Differences were observed between the two children in jaw kinematic variability, with one child exhibiting increased variability, while the other child demonstrated reduced or comparable variability compared to the control group. Possible sub-clinical impairments of jaw movement for speech were exhibited by two children who had sustained a TBI, providing insight into the consequences of TBI on speech motor control development.

Cytogenetics of jaw cysts - a pilot study.

Science.gov (United States)

Manor, Esther; Brennan, Peter A; Bodner, Lipa

2012-07-01

The pathogenesis of cysts that arise in the jaws is still not certain, and the underlying mechanisms of epithelial proliferation are not fully understood. Cysts of the jaw may involve a reactive, inflammatory, or neoplastic process. Cytogenetics, the study of the number and structure of chromosomes, has provided valuable information about the diagnosis, prognosis, and targeted treatment in many cancers, including oral squamous cell carcinoma. Cytogenetics can also provide information about the possible aetiology or neoplastic potential of a lesion, though to our knowledge no studies of this technique have been used for cysts in the jaws. In this pilot study we used cytogenetics in a series of 10 cysts (3 radicular, 4 dentigerous, 2 of the nasopalatine duct, and 1 dermoid). In all cases we found normal karyotypes. Further work and larger numbers are needed for a definitive study, but we can hypothesise from this pilot study that these cysts do not have cytogenetic aberrations and so have no neoplastic potential. Copyright © 2011 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

Fractures of the Jaw and Midface

Science.gov (United States)

... switch to the Professional version Home Injuries and Poisoning Facial Injuries Fractures of the Jaw and Midface Symptoms Diagnosis Treatment Treatment of mandible fractures Treatment of maxillary fractures ...

Early diagnosis of osteomyelitis occurred in the jaws

International Nuclear Information System (INIS)

Choi, Eun Sook; Na, Seung Mog; Lee, Un Gyeong; Koh, Kwang Joon

1994-01-01

Early diagnosis and treatment of osteomyelitis provide good prognosis and prevent severe complications. Therefore, it is important to early diagnose and treat before the bony changes are observed in conventional radiograms. Authors experienced three cases of early osteomyelitis, and scintigrams were useful to differentiate them from other diseases. The purpose of this report was to aid in the early diagnosis and treatment of osteomyelitis occurred in the jaws. The characteristic features were as follows: 1. In clinical examination, the patients complained mild pain and localized swelling in the jaws. 2. In radiographic findings, the conventional radiograms showed relatively mild bony change in the jaws. 3. The more severe periosteal reactions were observed in radiograms in children than in adult patient. 4. It showed marked increased uptake of radioisotopes in all scintigrams. 5. The three phase bone scanning were helpful to differentiate osteomyelitis from soft tissue diseases.

Epidemiological Data and Survival Rate of Removable Partial Dentures

Science.gov (United States)

Moreno, Amália; Haddad, Marcela Filié; Rocha, Eduardo Passos; Assunção, Wirley Gonçalves; Filho, Humberto Gennari; Santos, Emerson Gomes Dos; Sonego, Mariana Vilela; Santos, Daniela Micheline Dos

2016-01-01

Introduction The use of removable partial denture (RPD) is considered as low-cost and common treatment option to rehabilitate edentulous areas. Aim This study aimed to investigate the epidemiological data of patients rehabilitated with removable partial denture (RPD) in order to assess treatment survival rate and failures. Materials and Methods Epidemiological data and medical records of patients treated with RPD between 2007 and 2012 at the RPD discipline of a Brazilian University (Aracatuba Dental School- UNESP) were evaluated as well as dental records of patients who underwent RPD treatments (fabrication or repairs) between 2000 and 2010. Factors such as gender, age, presence of systemic disease, main complaint, edentulous arch, period and cause of denture replacement and the prosthesis characteristics were recorded. The chi-square test was used to assess the differences between the variables and the Kaplan Meyer to assess the survival of the RPDs evaluated. Results A total of 324 maxillary RPD and 432 mandibular RPD were fabricated. Most of the patients were women aging 41 to 60-year-old. The number of mandibular RPD Kennedy class I (26%) was statistically higher for the maxillary arch (p<.05). There was no association between main complaint to gender or the presence of systemic disease. The lingual plate was the most common major connector used in the mandible (32%). The main reason for altering the design of replaced RPDs were changes during treatment plan. Conclusion The number of patients who require RPD is large; most of RPDs are Kennedy Class I. A good treatment plan is very important for achieving a positive treatment outcome, and it is strictly related to the survival rate. PMID:27437367

The ideal male jaw angle--An Internet survey.

Science.gov (United States)

Mommaerts, Maurice Y

2016-04-01

The ideal male jaw angle has not been established. With the advent of additive manufacturing, precise customized shaping is a reality. This study aimed to define the ideal masculine mandibular angle as an aid for 3-dimensional (3D) design. An Internet survey was conducted using black/white photographs of celebrities and non-celebrities. Preferences regarding gonial angle (profile and frontal views), intergonial width and vertical jaw angle position (face frontal view), and angle curvature and definition in oblique views were obtained using simplified, unbalanced Likert scales. Constructs were defined for planning 3D implant designs. The preferred jaw angle had these characteristics: 130° in face profile view, intergonial width similar to facial width, vertical position in frontal view at the oral commissure or at least not below the lower lip, jawline slope in the face frontal view nearly parallel to (with a maximum 15° downward deviation from) a line extending from the lateral canthus to the alare, ascending ramus slope 65°-75° to the Frankfort horizontal, and curvature in the oblique view visible from earlobe to chin and not pointy. Photogrammetric analysis of panel preferences lead to constructs with values useful for the design of 3D printed jaw angles. Copyright © 2016 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

In the Jaws of Death

DEFF Research Database (Denmark)

Clasen, Mathias

The horror film Jaws (Spielberg, 1975) terrified millions of movie-goers and continues to resonate with audiences, despite its implausible premise and zoologically dubious depiction of a vengeful great white shark. An evolutionary approach explains why the film captured audiences’ imaginations an...

Electronic speckle-pattern interferometry (ESPI) applied to the study of mechanical behavior of human jaws

Science.gov (United States)

Roman, Juan F.; Moreno de las Cuevas, Vincente; Salgueiro, Jose R.; Suarez, David; Fernandez, Paula; Gallas, Mercedes; Blanchard, Alain

1996-01-01

The study of the mechanical behavior of the human jaw during chewing is helpful in several specific medical fields that cover the maxillo-facial area. In this work, electronic speckle pattern interferometry has been applied to study dead jaw bones under external stress which simulates the deformations induced during chewing. Fringes obtained after subtraction of two images of the jaw, the image of the relaxed jaw and that of the jaw under stress, give us information about the most stressed zones. The interferometric analysis proposed here is attractive as it can be done in real time with the jaw under progressive stress. Image processing can be applied for improving the quality of fringes. This research can be of help in orthognathic surgery, for example in diagnosis and treatment of fractured jaws, in oral surgery, and in orthodontics because it would help us to know the stress dispersion when we insert an osseointegrated implant or place an orthodontic appliance, respectively. Studying fragments of human jaw some results about its elasticity and flexibility were obtained.

Development of 4D jaw movement visualization system for dental diagnosis support

Science.gov (United States)

Aoki, Yoshimitsu; Terajima, Masahiko; Nakasima, Akihiko

2004-10-01

A person with an asymmetric morphology of maxillofacial skeleton reportedly possesses an asymmetric jaw function and the risk to express temporomandibular disorder is high. A comprehensive analysis from the point of view of both the morphology and the function such as maxillofacial or temporomandibular joint morphology, dental occlusion, and features of mandibular movement pathways is essential. In this study, the 4D jaw movement visualization system was developed to visually understand the characteristic jaw movement, 3D maxillofacial skeleton structure, and the alignment of the upper and lower teeth of a patient. For this purpose, the 3D reconstructed images of the cranial and mandibular bones, obtained by computed tomography, were measured using a non-contact 3D measuring device, and the obtained morphological images of teeth model were integrated and activated on the 6 DOF jaw movement data. This system was experimentally applied and visualized in a jaw deformity patient and its usability as a clinical diagnostic support system was verified.

Anthropometrics of mental foramen in dry dentate and edentulous mandibles in Coastal Andhra population of Andhra Pradesh State

Directory of Open Access Journals (Sweden)

Srinivas Moogala

2014-01-01

Full Text Available Aim: The aim of this study is to determine the morphological features and morphometrics of mental foramen with reference to surrounding anatomical landmarks in Coastal Andhra population of Andhra Pradesh State. Materials and Methods: Two-hundred and nineteen dry dentate and edentulous mandibles are examined in this study. Out of these 127 were dentate and 92 were edentulous. Various morphological and morphometrical parameters were measured by using digital Vernier caliper, metallic wire and metallic scale on both the right and left sides. Results: In the present study, the distance between most anterior margin of mental foramen and posterior border of ramus of the mandible is [MF-PR], MF-PR is 69.61 ± 6.03 mm on the right side and is 69.17 ± 6. 0 mm on left side in dentate mandible. In edentulous type, MF-PR is 68.39 ±6.4 mm on right side and 68.81 ± 6.55 mm on left side. In the present study, the distance between symphysis menti and most anterior margin of mental foramen [MF-SM] in dentate mandible is 28.24 ± 5.09 mm on right side and is 27.45 ± 3.7 mm on left side. In edentulous mandible (MF-SM is 28.51 ± 4.5 mm on right side and on left side is 27.99 ± 4.50 mm. Conclusion: Acquiring the knowledge and importance of anatomy of mental foramen is helpful in avoiding neurovascular complications, during regional anesthesia, peri apical surgeries, nerve repositioning and dental implant placement.

[Osteonecrosis of the jaws and bisphosphonates].

Science.gov (United States)

Junod, A F; Carrel, J-P; Richter, M; Vogt-Ferrier, N

2005-11-02

Widely prescribed, bisphosphonates inhibit bone resorption. They are not metabolised and have long half-lives. Two cases of osteonecrosis of the jaws have recently been attributed to bisphosphonates at the University Hospital of Geneva. The recent literature reveals more than a hundred similar cases throughout the world. Bone exposure appears spontaneously or after dental care. Treatment of the osteonecrosis is controversial and cure very difficult. This pathology is usually seen in patients on chemotherapy, steroids and i.v. bisphosphonates, but is sometimes seen with low-dose p.o. bisphosphonates. In view of the strong association between bisphosphonate therapy and osteonecrosis of the jaw, specialists have recommended dental and oral evaluation during bisphosphonate therapy as well as for several years after drug discontinuation.

Developing a software for removable partial denture design: Part II: Introduction of RPD graph software

Directory of Open Access Journals (Sweden)

Nejatidanesh F

2007-06-01

Full Text Available Background and Aim: Designing removable partial dentures is one of the most important phases of prosthetic treatments. Computer can be used to facilitate and increase accuracy of removable partial denture design. The aim of this study was to develop a software for removable partial denture design.Materials and Methods: A questionnaire (discussed in part I and major textbooks, were used to determine the design rules.  The software (RPD Graph was developed using Visual C++ and Maryam program. The RPD Graph can determine the classification of partial edentulous arch. With defining the missing teeth and providing data about prognosis and conditions of abutment teeth, the removable partial design will be developed by RPD Graph. This software is a knowledge-based system which has specific characteristics. It can be used as an educational tool for teaching RPD design and as a clinical tool for supporting clinician's decision. In addition it can be developed to more complete softwares.

Comparative jaw muscle anatomy in kangaroos, wallabies, and rat-kangaroos (marsupialia: macropodoidea).

Science.gov (United States)

Warburton, Natalie Marina

2009-06-01

The jaw muscles were studied in seven genera of macropodoid marsupials with diets ranging from mainly fungi in Potorous to grass in Macropus. Relative size, attachments, and lamination within the jaw adductor muscles varied between macropodoid species. Among macropodine species, the jaw adductor muscle proportions vary with feeding type. The relative mass of the masseter is roughly consistent, but grazers and mixed-feeders (Macropus and Lagostrophus) had relatively larger medial pterygoids and smaller temporalis muscles than the browsers (Dendrolagus, Dorcopsulus, and Setonix). Grazing macropods show similar jaw muscle proportions to "ungulate-grinding" type placental mammals. The internal architecture of the jaw muscles also varies between grazing and browsing macropods, most significantly, the anatomy of the medial pterygoid muscle. Potoroines have distinctly different jaw muscle proportions to macropodines. The masseter muscle group, in particular, the superficial masseter is enlarged, while the temporalis group is relatively reduced. Lagostrophus fasciatus is anatomically distinct from other macropods with respect to its masticatory muscle anatomy, including enlarged superficial medial pterygoid and deep temporalis muscles, an anteriorly inflected masseteric process, and the shape of the mandibular condyle. The enlarged triangular pterygoid process of the sphenoid bone, in particular, is distinctive of Lagsotrophus. (c) 2009 Wiley-Liss, Inc.

Influence of maximum bite force on jaw movement during gummy jelly mastication.

Science.gov (United States)

Kuninori, T; Tomonari, H; Uehara, S; Kitashima, F; Yagi, T; Miyawaki, S

2014-05-01

It is known that maximum bite force has various influences on chewing function; however, there have not been studies in which the relationships between maximum bite force and masticatory jaw movement have been clarified. The aim of this study was to investigate the effect of maximum bite force on masticatory jaw movement in subjects with normal occlusion. Thirty young adults (22 men and 8 women; mean age, 22.6 years) with good occlusion were divided into two groups based on whether they had a relatively high or low maximum bite force according to the median. The maximum bite force was determined according to the Dental Prescale System using pressure-sensitive sheets. Jaw movement during mastication of hard gummy jelly (each 5.5 g) on the preferred chewing side was recorded using a six degrees of freedom jaw movement recording system. The motion of the lower incisal point of the mandible was computed, and the mean values of 10 cycles (cycles 2-11) were calculated. A masticatory performance test was conducted using gummy jelly. Subjects with a lower maximum bite force showed increased maximum lateral amplitude, closing distance, width and closing angle; wider masticatory jaw movement; and significantly lower masticatory performance. However, no differences in the maximum vertical or maximum anteroposterior amplitudes were observed between the groups. Although other factors, such as individual morphology, may influence masticatory jaw movement, our results suggest that subjects with a lower maximum bite force show increased lateral jaw motion during mastication. © 2014 John Wiley & Sons Ltd.

Bar versus ball attachments for implant-supported overdentures in complete edentulism: A systematic review.

Science.gov (United States)

Anas El-Wegoud, Marwah; Fayyad, Ahmed; Kaddah, Amal; Nabhan, Ashraf

2018-04-01

Implant-supported overdenture is one of the most predictable treatment options used in complete edentulism. However, differences have been reported between bar and ball attachments used to retain overdentures in terms of patient satisfaction and prosthesis retention. The purpose of this study is to compare the effectiveness of bar and ball attachments for conventionally loaded implant-supported overdentures in completely edentulous patients to improve patient satisfaction and prosthesis retention. We conducted the review according to the Cochrane methods and following MECIR standards. We searched Cochrane Oral Health Group Trial register, Cochrane Central Register of Controlled Trials, MEDLINE, and the WHO ICTRP (March 31, 2017). Two review authors assessed trials for inclusion and risk of bias, extracted data, and checked for accuracy. We have expressed results as risk ratio or mean differences, together with their 95% confidence intervals. We included 10 trials (465 participants). After 5 y, one trial reported higher patient satisfaction when bar attachment was used (MD 1.30, 95% CI 0.20-2.40), and reported no difference between both systems in prosthesis retention (MD -0.90, 95% CI -1.90 to 0.10). Two trials reported no implant failures after 1 and 5 y in both attachments. Downgrading of evidence was based on the unclear risk of bias of included studies and the wide CI crossing the line of no effect. There is insufficient evidence to support bar or ball attachment to be used with implant-supported overdentures in completely edentulous patients to improve patient satisfaction and prosthesis retention (PROSPERO 2014:CRD42014014594). © 2017 Wiley Periodicals, Inc.

Jaw Dislocation as an Unusual Complication of Upper Endoscopy

Directory of Open Access Journals (Sweden)

Evan S. Dellon

2016-05-01

Full Text Available This case report presents an unusual complication of upper endoscopy, resulting in jaw dislocation. Temporomandibular joint dislocation is commonly reported in association with anesthesia and intubation, but it is not widely recognized as a complication of gastrointestinal endoscopy. This report also reviews the current literature regarding this complication and discusses the potential causes of dislocation, differential diagnoses for jaw pain following endoscopy, and recommendations for prevention.

Patterns of variation across primates in jaw-muscle electromyography during mastication.

Science.gov (United States)

Vinyard, Christopher J; Wall, Christine E; Williams, Susan H; Hylander, William L

2008-08-01

Biologists that study mammals continue to discuss the evolution of and functional variation in jaw-muscle activity during chewing. A major barrier to addressing these issues is collecting sufficient in vivo data to adequately capture neuromuscular variation in a clade. We combine data on jaw-muscle electromyography (EMG) collected during mastication from 14 species of primates and one of treeshrews to assess patterns of neuromuscular variation in primates. All data were collected and analyzed using the same methods. We examine the variance components for EMG parameters using a nested ANOVA design across successive hierarchical factors from chewing cycle through species for eight locations in the masseter and temporalis muscles. Variation in jaw-muscle EMGs was not distributed equally across hierarchical levels. The timing of peak EMG activity showed the largest variance components among chewing cycles. Relative levels of recruitment of jaw muscles showed the largest variance components among chewing sequences and cycles. We attribute variation among chewing cycles to (1) changes in food properties throughout the chewing sequence, (2) variation in bite location, and (3) the multiple ways jaw muscles can produce submaximal bite forces. We hypothesize that variation among chewing sequences is primarily related to variation in properties of food. The significant proportion of variation in EMGs potentially linked to food properties suggests that experimental biologists must pay close attention to foods given to research subjects in laboratory-based studies of feeding. The jaw muscles exhibit markedly different variance components among species suggesting that primate jaw muscles have evolved as distinct functional units. The balancing-side deep masseter (BDM) exhibits the most variation among species. This observation supports previous hypotheses linking variation in the timing and activation of the BDM to symphyseal fusion in anthropoid primates and in strepsirrhines

Análise fotoelástica da distribuição de tensões produzida na mandíbula pela simulação do esforço mastigatório em sobredentaduras muco-dento-suportadas e prótese total Photoelastic analysis of stress distribution in jaws under masticatory efforts simulation in overdentures and conventional complete denture

Directory of Open Access Journals (Sweden)

Marcos André Kalabaide VAZ

1999-01-01

photoelastic material were made with double impression modelling technique from a edentulous human jaw. The molds were filled with photoelastic resin PLM-4 (Photolastic Inc., Raleigh, USA. A variation of root dispositions were made on jaws, separating them in three groups; Group I, without roots (control group; Group II, bilateral disposition of roots in the dental arch corresponding to two canines; Group III, one canine and a molar root disposed at the same hemi-arch in an unilateral situation. Conventional complete dentures and overdentures were made over these jaws that ocluded an acrilic cast fixed in a semi-adjustable articulator for the loading aplication (20 N. After "stress freezing", the models were cut off in their median line and analized on a transmission polariscope (Photolastic Inc., Raleigh, USA. Throughout the photoelastic frangent analysis it was concluded that: 1 all the photoelastic models (groups I, II and III showed different patterns of stress distribution; 2 Group I showed a great concentration of stress all over the residual ridge; 3 Group II was the best in stress distribution when compared with the other groups. The high concentration of stress at the root apex decreased its concentration over all edentulous region of the arch; 4 In Group III a greater effort concentration was observed at the roots apex and also in the edentulous region.

An examination of the degrees of freedom of human jaw motion in speech and mastication.

Science.gov (United States)

Ostry, D J; Vatikiotis-Bateson, E; Gribble, P L

1997-12-01

The kinematics of human jaw movements were assessed in terms of the three orientation angles and three positions that characterize the motion of the jaw as a rigid body. The analysis focused on the identification of the jaw's independent movement dimensions, and was based on an examination of jaw motion paths that were plotted in various combinations of linear and angular coordinate frames. Overall, both behaviors were characterized by independent motion in four degrees of freedom. In general, when jaw movements were plotted to show orientation in the sagittal plane as a function of horizontal position, relatively straight paths were observed. In speech, the slopes and intercepts of these paths varied depending on the phonetic material. The vertical position of the jaw was observed to shift up or down so as to displace the overall form of the sagittal plane motion path of the jaw. Yaw movements were small but independent of pitch, and vertical and horizontal position. In mastication, the slope and intercept of the relationship between pitch and horizontal position were affected by the type of food and its size. However, the range of variation was less than that observed in speech. When vertical jaw position was plotted as a function of horizontal position, the basic form of the path of the jaw was maintained but could be shifted vertically. In general, larger bolus diameters were associated with lower jaw positions throughout the movement. The timing of pitch and yaw motion differed. The most common pattern involved changes in pitch angle during jaw opening followed by a phase predominated by lateral motion (yaw). Thus, in both behaviors there was evidence of independent motion in pitch, yaw, horizontal position, and vertical position. This is consistent with the idea that motions in these degrees of freedom are independently controlled.

Effect of different head-neck-jaw postures on cervicocephalic kinesthetic sense.

Science.gov (United States)

Zafar, H; Alghadir, A H; Iqbal, Z A

2017-12-01

To investigate the effect of different induced head-neck-jaw postures on head-neck relocation error among healthy subjects. 30 healthy adult male subjects participated in this study. Cervicocephalic kinesthetic sense was measured while standing, habitual sitting, habitual sitting with clenched jaw and habitual sitting with forward head posture during right rotation, left rotation, flexion and extension using kinesthetic sensibility test. Head-neck relocation error was least while standing, followed by habitual sitting, habitual sitting with forward head posture and habitual sitting with jaw clenched. However, there was no significant difference in error between different tested postures during all the movements. To the best of our knowledge, this is the first study to see the effect of different induced head-neck-jaw postures on head-neck position sense among healthy subjects. Assuming a posture for a short duration of time doesn't affect head-neck relocation error in normal healthy subjects.

Expression of Msx-1 is suppressed in bisphosphonate associated osteonecrosis related jaw tissue-etiopathology considerations respecting jaw developmental biology-related unique features

Directory of Open Access Journals (Sweden)

Schlegel Karl A

2010-10-01

Full Text Available Abstract Background Bone-destructive disease treatments include bisphosphonates and antibodies against the osteoclast differentiator, RANKL (aRANKL; however, osteonecrosis of the jaw (ONJ is a frequent side-effect. Current models fail to explain the restriction of bisphosphonate (BP-related and denosumab (anti-RANKL antibody-related ONJ to jaws. Msx-1 is exclusively expressed in craniofacial structures and pivotal to cranial neural crest (CNC-derived periodontal tissue remodeling. We hypothesised that Msx-1 expression might be impaired in bisphosphonate-related ONJ. The study aim was to elucidate Msx-1 and RANKL-associated signal transduction (BMP-2/4, RANKL in ONJ-altered and healthy periodontal tissue. Methods Twenty ONJ and twenty non-BP exposed periodontal samples were processed for RT-PCR and immunohistochemistry. An automated staining-based alkaline phosphatase-anti-alkaline phosphatase method was used to measure the stained cells:total cell-number ratio (labelling index, Bonferroni adjustment. Real-time RT-PCR was performed on ONJ-affected and healthy jaw periodontal samples (n = 20 each to quantitatively compare Msx-1, BMP-2, RANKL, and GAPDH mRNA levels. Results Semi-quantitative assessment of the ratio of stained cells showed decreased Msx-1 and RANKL and increased BMP-2/4 (all p Conclusions These results explain the sclerotic and osteopetrotic changes of periodontal tissue following BP application and substantiate clinical findings of BP-related impaired remodeling specific to periodontal tissue. RANKL suppression substantiated the clinical finding of impaired bone remodelling in BP- and aRANKL-induced ONJ-affected bone structures. Msx-1 suppression in ONJ-adjacent periodontal tissue suggested a bisphosphonate-related impairment in cellular differentiation that occurred exclusively jaw remodelling. Further research on developmental biology-related unique features of jaw bone structures will help to elucidate pathologies restricted to

Nueva indicación de implantes cigomáticos para la rehabilitación fija de desdentados parciales: reporte de un caso A new indication for Zygomatic implants for the fixed rehabilitation of the partially edentulous patient: Case report

Directory of Open Access Journals (Sweden)

M.F. Pintor Willcock

2007-08-01

Full Text Available Los implantes cigomáticos están indicados en casos de reabsorciones maxilares severas. Esto permitiría eliminar la necesidad de injertos óseos o levantamientos de seno de manera de recuperar el volumen óseo necesario para rehabilitar en base a implantes convencionales, disminuyendo así la morbilidad y el tiempo de tratamiento. A continuación presentamos caso de paciente desdentado parcial superior, clase I de Kennedy, en el cual se utilizaron dos implantes cigomáticos a cada lado, emergiendo sobre el reborde, a través de una modificación de la técnica.Zygomatic Implants are used in the rehabilitation of severely resorbed maxillas. This eliminates the necessity of bone grafting or sinus augmentation to restore the osseous volume necessary for conventional implant rehabilitation. This also minimizes morbidity and treatment times. We present the case of a patient with a partially edentulous upper ridge, Kennedy class I, in whom two zygomatic implants were placed in each side, that emerged over the alveolar ridge crest as a result of a technique modification.

The oral microbial community of gingivitis and lumpy jaw in captive macropods.

Science.gov (United States)

Antiabong, John F; Boardman, Wayne; Moore, Robert B; Brown, Melissa H; Ball, Andrew S

2013-12-01

Gingivitis and lumpy jaw are diseases of polymicrobial aetiology. Although Fusobacterium necrophorum has been associated with these diseases in macropods, little is known about other organisms associated with these diseases in this animal species. PCR-DGGE analysis revealed the potential pathogens associated with gingivitis and lumpy jaw in macropods. PCR-DGGE profile comparison between the healthy and disease groups indicated a shift in the oral bacterial community structures with similarity coefficients of 48% and 35% for gingivitis and lumpy jaw respectively. Moreover, gingivitis was associated with increase in bacterial diversity (Shannon index = 2.87; PL curve = 45%) while lumpy jaw resulted in a decline in bacterial diversity (Shannon index = 2.47; PL curve = 74%). This study suggest that the establishment of gingivitis and lumpy jaw diseases follows the ecological plaque hypothesis. This forms the basis for an expanded investigation in an epidemiological scale and suggests the need for the appropriate choice of antimicrobial agent(s) and for the effective management and control of polymicrobial diseases. Copyright © 2013 Elsevier Ltd. All rights reserved.

Comparison of nonexposed and exposed bisphosphonate-induced osteonecrosis of the jaws

DEFF Research Database (Denmark)

Schiodt, Morten; Reibel, Jesper; Oturai, Peter

2014-01-01

Nonexposed osteonecrosis of the jaws (NE-ONJ) does not fit into the current definition of osteonecrosis, which requires exposed bone. A modification of the classification of bisphosphonate-induced osteonecrosis of the jaws (ONJ) is proposed. This study aimed to test proposed criteria for NE...

Reliability and Validity of a Nepalese Version of the Oral Health Impact Profile for Edentulous Subjects.

Science.gov (United States)

Shrestha, Bidhan; Niraula, Surya Raj; Parajuli, Prakash K; Suwal, Pramita; Singh, Raj Kumar

2018-06-01

To assess the reliability and to validate the translated Nepalese version of the Oral Health Impact Profile (OHIP-EDENT-N) in Nepalese edentulous subjects. The international guidelines for translation and cross-cultural adaption of OHIP-EDENT were followed, and a Nepalese version of the questionnaire was adapted for this study. Eighty-eight completely edentulous subjects were then selected for the study and completed their responses for the questionnaire. The reliability of the OHIP-EDENT-N was evaluated using internal consistency. Validity was assessed as construct and convergent validity. Construct validity was determined using exploratory factor analysis (EFA). The correlation between OHIP-EDENT-N subscale scores and the global question was investigated to test the convergent validity. Cronbach's alpha for the total score of OHIP-EDENT-N was 0.78. Construct validity was assessed by factor analysis: 70.196% of the variance was accountable to five factors extracted from the factor analysis. Factor loadings above 0.40 were noted for all items. In terms of convergent validity, significant correlations could be established between OHIP-EDENT-N and global questions. This study has been able to establish the reliability and validity of the OHIP-EDENT-N, and OHIP-EDENT-N can be a considered a reliable tool to assess the oral health related quality of life in the Nepalese edentulous population. © 2016 by the American College of Prosthodontists.

The influence of jaw's curvature on the results of the Brazilian disc test

Directory of Open Access Journals (Sweden)

Ch.F. Markides

2016-04-01

Full Text Available The general contact problem of a disc squeezed between jaws of arbitrary curvature is considered employing Muskhelishvili's complex potentials. Taking advantage of the general solution introduced, the closed-form expressions for the stresses along strategic loci (loaded rim, loaded diameter, disc's center are obtained, in terms of the ratio ρ of the disc's to the jaw's curvature. Then, the effect of ρ (as well as that of the relative stiffness of the disc's and jaw's materials dictating the contact arc on the stress distribution along these loci is explored. It is concluded that, for both smooth contact (zero friction and contact with friction, the role of the jaw's curvature is significant not only along the disc-jaw contact arc (as it could be expected, but also all along the loaded diameter. On the other hand, it is indicated that the stress field at the disc's center is more or less insensitive to the jaw's curvature assuming that ρ lies within the range (0, 0.67 or in other words within the limits defined by the two standardized suggestions, i.e. that of American Society for Testing and Materials (ASTM (plane loading platens with ρ = 0 and that of International Society for Rock Mechanics (ISRM (curved jaws with ρ = 0.67. The upper limit of this range is a kind of compromise between the need to make the stress field at the disc's center independent of the boundary conditions while keeping at the same time the contact angle large enough to reduce the stress concentration and the risk for premature fracture initiation far from the disc's center. For jaws with radius of curvature exceeded by that suggested by ISRM, the stress field at the disc's center is significantly influenced. Especially for jaws with radius approaching that of the disc, the stress field at the disc's center is dramatically distorted rendering Hondros' formula inapplicable and the test results erroneous.

Interventions for replacing missing teeth: partially absent dentition.

Science.gov (United States)

Abt, Elliot; Carr, Alan B; Worthington, Helen V

2012-02-15

Management of individuals presenting with partial loss of teeth is a common task for dentists. Outcomes important to the management of missing teeth in the partially absent dentition should be systematically summarized. This review recognizes both the challenges associated with such a summarization and the critical nature of the information for patients. To assess the effects of different prostheses for the treatment of partially absent dentition in terms of the following outcomes: long-term success, function, morbidity and patient satisfaction. We searched the Cochrane Oral Health Group's Trials Register (to 21 March 2011), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2011, Issue 1), MEDLINE via OVID (1950 to March 2011) and EMBASE via OVID (1980 to March 2011). There were no restrictions regarding language or date of publication. We contacted several authors to identify non-published trials. Randomized controlled trials (RCTs) comparing different methods (including the design and materials used) of treating partial edentulism, with clinically relevant outcomes, were included in this review. Trials reporting only surrogate outcomes, such as plaque accumulation or gingival volume, were excluded from this review. Two review authors independently carried out the screening of eligible studies, assessment of dimensions of quality of trials, and data extraction. Results were expressed as mean differences for continuous data, risk ratios for dichotomous outcomes, and hazard ratios with 95% confidence intervals for time-to-event data. Twenty-one trials met the inclusion criteria for this review. Twenty-four per cent of these were assessed as being at high risk of bias and the remainder were at unclear risk of bias. The clinical heterogeneity among the included studies precluded any attempt at meta-analysis. There was insufficient evidence to determine whether one type of removable dental prosthesis (RDP) was better or worse than

Technical Considerations in Rehabilitation of an Edentulous Total Glossectomy Patient

Directory of Open Access Journals (Sweden)

Pravin Bhirangi

2012-01-01

Full Text Available The technician by virtue of his profession plays an important role in fabricating silicone tongue prosthesis for a total glossectomy patient. The technician, with his skills and specialized knowledge in handling material, plays a valuable role as a member of the oncology team. A patient with total glossectomy can be rehabilitated by silicone tongue prosthesis as an aid to improve his speech and swallowing. This paper describes the technical steps involved in fabricating a silicone tongue prosthesis for an edentulous total glossectomy patient.

Dislocation of jaws

International Nuclear Information System (INIS)

Katzberg, R.W.; Hayakawa, K.; Anderson, Q.N.; Manzione, J.V.; Helms, C.A.; Tallents, R.

1984-01-01

Pluri-directional tomographic and arthrotomographic findings are described in six patients with dislocation of the jaw severe enough to require medical assistance. A grooved defect along the posterior aspect of the condylar head was noted in two of the six patients. The arthrotomographic findings that were obtained in one patient that was dislocated at the time of the arthrogram did not suggest a meniscocondyle incoordination as a mechanism. However, arthrotomographic findings in the six reported cases suggest that significant intra-articular soft tissue damage may result. (orig.)

Occlusal plane location in edentulous patients: a review.

Science.gov (United States)

Shetty, Sanath; Zargar, Nazia Majeed; Shenoy, Kamalakanth; Rekha, V

2013-09-01

Occlusal plane orientation is an important factor in the construction of a complete denture. Occlusal plane could be oriented using landmarks in the mandibular arch as well as in the maxillary arch. In the mandibular arch there are few landmarks which could be used to orient the occlusal plane like the retromolar pad, corner of the lips (lower lip length) whereas the maxillary arch has a number of landmarks, of which the ala-tragal line is the most commonly used and the same being the most controversial. In the following article different landmarks and its accuracy for orientating the occlusal plane in an edentulous subject as studied by various authors has been discussed.

REHABILITATION OF SEVERELY ATROPHIED UPPER JAW WITH INTRAOSSAL DENTAL IMPLANTS - clinical case

OpenAIRE

Ivan Chenchev; Radka Cholakova; Cvetan Cvetanov; Ir. Mitarcheva

2010-01-01

Objective: The purpose of this presentation is to show the difficulty in prosthetization of a clinical case with a pronounced atrophy of the upper jaw and the various types and nature of restrictions imposed by the requirements of the patient. Methods: The clinical analysis, surgical protocol and prosthetic solution are presented in the treatment of 72 year-old woman with a pronounced atrophy of the upper jaw. OPG, standard CT of the upper jaw was used in the planning and a special surgical t...

[Influence of attachment type on stress distribution of implant-supported removable partial dentures].

Science.gov (United States)

Yang, Xue; Rong, Qi-guo; Yang, Ya-dong

2015-02-18

To compare influences of different retention attachments on stress among supporting structures. By 3-dimensional laser scanner and reverse engineering computer aided design (CAD) software, a basic partially edentulous digital model with mandibular premolar and molar missing was established. Implant attachment and removable partial dentures (RPD) were added into the basic model to build three kinds of models: RPD only, RPD + implant + Locator attachment, and RPD + implant + Magfit attachment. Vertical and inclined loads were put on artificial teeth unilaterally. By means of 3-dimensional finite element analysis, the stress distribution and displacement of the main supportive structures were compared. A complete 3-dimensional finite element model was established, which contained tooth structure, and periodontal structures. The displacement of the denture was smaller in Locator (9.38 μm vertically, 45.48 μm obliquely) and Magfit models (9.54 μm vertically, 39.45 μm obliquely) compared with non-implant RPD model (95.27 μm vertically, 155.70 μm obliquely). Compared with the two different attachments, cortical bone stress value was higher in Locator model (Locator model 10.850 MPa vertically, 43.760 MPa obliquely; Magfit model 7.100 MPa vertically, 19.260 MPa obliquely).The stress value of abutment periodontal ligamentin Magfit model (0.420 MPa vertically) was lower than that in Locator model (0.520 MPa vertically). The existence of implant could reduce maximum von Mises value of each supportive structure when Kennedy I partially edentulous mandible was restored. Comparing the structure of Magfit and Locator attachment, the contact of Magfit attachment was rigid, while Locator was resilient. Locator attachment could improve stability of the denture dramatically. Locator had stronger effect on defending horizontal movement of the denture.

Dental CT: imaging technique, anatomy, and pathologic conditions of the jaws

International Nuclear Information System (INIS)

Gahleitner, Andre; Watzek, G.; Imhof, H.

2003-01-01

In addition to conventional imaging methods, dental CT has become an established method for anatomic imaging of the jaws prior to dental implant placement. More recently, this high-resolution imaging technique has gained importance in diagnosing dental-associated diseases of the mandible and maxilla. Since most radiologists have had little experience in these areas, many of the CT findings remain undescribed. The objective of this review article is to present the technique of dental CT, to illustrate the typical appearance of jaw anatomy and dental-related diseases of the jaws with dental CT, and to show where it can serve as an addition to conventional imaging methods in dental radiology. (orig.)

Dental CT: imaging technique, anatomy, and pathologic conditions of the jaws

Energy Technology Data Exchange (ETDEWEB)

Gahleitner, Andre [Department of Radiology/Osteology, Medical School, University of Vienna, Waehringer Strasse 25a, 1090 Vienna (Austria); Department of Oral Surgery, Dental School, University of Vienna, Waehringer Strasse 25a, 1090 Vienna (Austria); Watzek, G. [Department of Oral Surgery, Dental School, University of Vienna, Waehringer Strasse 25a, 1090 Vienna (Austria); Imhof, H. [Department of Radiology/Osteology, Medical School, University of Vienna, Waehringer Strasse 25a, 1090 Vienna (Austria)

2003-02-01

In addition to conventional imaging methods, dental CT has become an established method for anatomic imaging of the jaws prior to dental implant placement. More recently, this high-resolution imaging technique has gained importance in diagnosing dental-associated diseases of the mandible and maxilla. Since most radiologists have had little experience in these areas, many of the CT findings remain undescribed. The objective of this review article is to present the technique of dental CT, to illustrate the typical appearance of jaw anatomy and dental-related diseases of the jaws with dental CT, and to show where it can serve as an addition to conventional imaging methods in dental radiology. (orig.)

Epidemiology of ameloblastomas of the jaws; A report from the Netherlands

NARCIS (Netherlands)

Oomens, Marjolijn A. E. M.; van der Waal, Isaac

2014-01-01

Objectives: To provide epidemiological data of ameloblastomas of the jaws in the Netherlands over a 25-year time period (1985-2010) and to compare these data with data from other parts of the world. Material and Methods: The data of all patients diagnosed with a primary ameloblastoma of the jaws in

[Jaw osteosarcomas].

Science.gov (United States)

Steve, M; Ernenwein, D; Chaine, A; Bertolus, C; Goudot, P; Ruhin-Poncet, B

2011-11-01

Osteosarcoma (OS) is the most frequent bone malignant tumor. It is usually found on long bones, 5 to 10% are located on jaws, accounting for 0.5 to 1% of all facial tumors. There is little published data which concerns only few patients. Our aim was to study retrospectively cases of facial bone OS in adults, and to compare our results with published data to suggest an optimal management scheme. Thirty-three patients were managed for an OS, from January 1997 to January 2007. Fourteen patients with a maxillary and mandibular OS, treated in first-intention in our unit, were included. The following data were analyzed: age; personal history; circumstance of discovery; clinical, functional, and physical signs; loco-regional extension and metastasis radiological investigation. The histological slides were systematically reviewed. The protocol, therapeutic outcome, and follow-up were studied. The mean age at diagnosis was 43. Swelling was the most frequent functional sign. The mean delay before management was 3.4 months. The most frequent radiological presentation was a lytic and hyperdense image. The diagnosis was suggested after CT scan in 57.1% of cases. The biopsy was correlated to the anatomopathological analysis in 78.6% of cases. The most common treatment was surgical exeresis completed by chemotherapy. The 5-year survival rate was 50%. Jaw OS are specific because of their localization and specific bone ultrastructure. Their management remains controversial: should they be managed like limb OS or treated more specifically? Neoadjuvant chemotherapy, even if it delays exeresis for 3 months, seems to stop the growth or reduce the tumor. An early anatomopathological analysis of the surgical piece determines adjuvant therapy. The negative prognostic factors are: maxillary localization because of limited exeresis margins, tumoral size, and osteoblastic sub-type. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

Rehabilitation with implant-supported overdentures in total edentulous patients: A review

OpenAIRE

Martínez–Lage-Azorín, Juan F.; Segura-Andrés, Gustavo; Faus-López, Joan; Agustín-Panadero, Rubén

2013-01-01

Objectives: The main aim of this review article is to discuss implant-supported overdentures (ISOs) as treatment in edentulous patients. Besides, we will try to discuss among the different treatment options in such patients and to analyze their validity when ISOs are compared with other clinical modalities. At the same time, we will try to suggest clinical guidelines supported by current clinical studies. Material and methods: We performed a Medline search and review of pertinent articles on ...

SU-E-T-471: Small Field Jaw/MLC Reference Data

International Nuclear Information System (INIS)

Kerns, J; Alvarez, P; Followill, D; Lowenstein, J; Molineu, A; Summers, P; Kry, S

2014-01-01

Purpose: In recent years the need for small field data of MLCs has increased due to the use of intensity-modulated radiation (IMRT), but moreover the use of stereotactic body radiation (SBRT) has increased, which uses not simply small field sizes, but small jaw and field sizes together. Having reference data for these small fields that is reliable would be invaluable to the physics community. Our study has gathered these values and the data distributions from the Radiological Physics Center's (RPC) site visits between 1990 and the present. Methods: For all measurements, the RPC used a 25 × 25 × 25cm water phantom placed at 100cm SSD. All measurements were made with an Exradin A16 cylindrical ion chamber at an effective depth of 10 cm. A total of 42 Varian machine measurements were used to compose the data for a 6 MV beam and 5 TrueBeam 6 MV flattening filter free (FFF) beams were used for FFF data. Results: Jaw/MLC fields were measured for both 6 MV and 6 MF FFF beams with the jaws and MLCs both at the following field sizes: 6×6, 4×4, 3×3, and 2×2cm. Measurements were normalized to the 10×10 field readings (defined by the jaws and MLC). Spread in the data was minimal and demonstrates a high level of accuracy of acquired data. Conclusion: Small field Jaw/MLC reference data for Varian 6MV and 6 MV FFF beams has been analyzed and presented here, composed of the aggregation of numerous RPC site visits. Obtaining reliable small field data remains difficult, however the RPC has collected high fidelity small field Jaw/MLC data. The data are presented as a reference along with their distributions, in such a way that the physicist can act based upon their own desired agreement with the reference data

Leaf transmission reduction using moving jaws for dynamic MLC IMRT

International Nuclear Information System (INIS)

Schmidhalter, D.; Fix, M. K.; Niederer, P.; Mini, R.; Manser, P.

2007-01-01

The aim of this work is to investigate to what extent it is possible to use the secondary collimator jaws to reduce the transmitted radiation through the multileaf collimator (MLC) during an intensity modulated radiation therapy (IMRT). A method is developed and introduced where the jaws follow the open window of the MLC dynamically (dJAW method). With the aid of three academic cases (Closed MLC, Sliding-gap, and Chair) and two clinical cases (prostate and head and neck) the feasibility of the dJAW method and the influence of this method on the applied dose distributions are investigated. For this purpose the treatment planning system Eclipse and the Research-Toolbox were used as well as measurements within a solid water phantom were performed. The transmitted radiation through the closed MLC leads to an inhomogeneous dose distribution. In this case, the measured dose within a plane perpendicular to the central axis differs up to 40% (referring to the maximum dose within this plane) for 6 and 15 MV. The calculated dose with Eclipse is clearly more homogeneous. For the Sliding-gap case this difference is still up to 9%. Among other things, these differences depend on the depth of the measurement within the solid water phantom and on the application method. In the Chair case, the dose in regions where no dose is desired is locally reduced by up to 50% using the dJAW method instead of the conventional method. The dose inside the chair-shaped region decreased up to 4% if the same number of monitor units (MU) as for the conventional method was applied. The undesired dose in the volume body minus the planning target volume in the clinical cases prostate and head and neck decreased up to 1.8% and 1.5%, while the number of the applied MU increased up to 3.1% and 2.8%, respectively. The new dJAW method has the potential to enhance the optimization of the conventional IMRT to a further step

Annals of Medical and Health Sciences Research - Vol 1, No 1 (2011)

African Journals Online (AJOL)

Certain Red Blood Cell Indices of Maternal and Umbilical Cord Blood in Owerri, Nigeria: A Preliminary Report · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT ... A Survey of the Knowledge of Dental Implants as a Choice in Treatment of Edentulous Jaws among Health Workers in Government Dental Clinics in Enugu ...

Dental implants for severely atrophied jaws due to ectodermal dysplasia

Directory of Open Access Journals (Sweden)

Preetha Balaji

2015-01-01

Full Text Available The aim was to present the successful esthetical and functional rehabilitation of partial anodontia in a case of severe ectodermal dysplasia with complete atrophy of the jaws. A 17-year-old male with Class III malocclusion with partial anodontia sought dental implant treatment. His expectation was that of Class I occlusion. The challenge in the case was to match the expectation, reality, and the clinical possibilities. Ridge augmentation was performed with a combination of rib graft and recombinant human bone morphogenetic protein-2. Simultaneously, 6 implants (Nobel Biocare™ - Tapered Groovy were placed in maxillary arch and 10 in the mandible. Simultaneous placement ensured faster and better osseointegration though a mild compromise of the primary stability was observed initially. After adequate healing, Customized Zirconia Procera™ system was used to build the framework. Zirconia crown was cemented to the framework. Radiological and clinical evidence of osseointegration was observed in all 16 dental implants. Successful conversion of Class III to Class I occlusion was achieved with the combination of preprosthetic alveolar ridge augmentation, Procera™ Implant Bridge system. Abnormal angulations and or placement of dental implants would result in failure of the implant. Hence conversion of Class III to Class I occlusion needs complete and complex treatment planning so that the entire masticatory apparatus is sufficiently remodeled. Planning should consider the resultant vectors that would otherwise result in failure of framework or compromise the secondary stability of the dental implant during function. A successful case of rehabilitation of complex partial anodontia is presented.

The effect of implant-supported removable partial dentures on oral health quality of life.

Science.gov (United States)

Gates, W Day; Cooper, Lyndon F; Sanders, Anne E; Reside, Glenn J; De Kok, Ingeborg J

2014-02-01

Removable partial dentures (RPDs) represent standard treatment for partial edentulism despite major shortcomings. To alleviate these shortcomings, endosseous implants provide support and stability as well as contribute to maintenance of alveolar bone. This prospective, within subject, time series study evaluated patient-based outcomes of RPDs compared to implant-supported removable partial dentures (ISRPDs). The study hypothesis was that the ISRPD would substantially improve oral health quality of life for patients. Seventeen patients requesting new mandibular Kennedy I or II RPDs received one 6-mm dental implant in one or both of the posterior edentulous areas. After healing, conventional RPDs were fabricated and delivered. Twelve weeks later, second-stage surgery was performed, and ball abutments with Clix attachments were inserted, thereby converting the prostheses to ISRPDs. Oral health quality of life was evaluated using the 49-item Oral Health Impact Profile (OHIP-49) questionnaire. The OHIP-49 was administered prior to treatment (baseline), at 6 and 12 weeks following RPD delivery and at 6 and 12 weeks following ISRPD conversion. Radiographic evaluation was performed at 6 and 12 weeks following ISRPD conversion. In statistical analysis, a fixed-slope random intercept variance components model took account of the multiple observations per person over time. In 17 subjects, 29 of 30 implants survived. The failed implant was replaced without complications. Abutment complications were limited to one abutment loosening and one attachment replacement. Minor prosthodontic complications were recorded. The OHIP-49 score reduced by 11.8 points, on average, at 12 weeks following ISRPD conversion (P = 0.011). Patients reported improved oral health following conversion to an ISRPD from RPD. The ISRPD involving short implants is one treatment option that should be considered when treatment planning Kennedy Class I and II patients. © 2012 John Wiley & Sons A/S.

Hyperparathyroidism-jaw tumour syndrome detected by aggressive generalized osteitis fibrosa cystica.

Science.gov (United States)

Guerrouani, Alae; Rzin, Abdelkader; El Khatib, Karim

2013-01-01

Severe hyperparathyroidism can affect bone metabolism and be in the origine of multiple brown tumours (generalized osteitis fibrosa cystica). When associated with fibro-ossifying tumours of the jaw, it realizes a rare genetic syndrome referred as Hyperparathyroidism-jaw tumour HPT-JT. We report the case of a patient we treated for HPT-JT, and literature review.

Directional selection has shaped the oral jaws of Lake Malawi cichlid fishes.

Science.gov (United States)

Albertson, R Craig; Streelman, J Todd; Kocher, Thomas D

2003-04-29

East African cichlid fishes represent one of the most striking examples of rapid and convergent evolutionary radiation among vertebrates. Models of ecological speciation would suggest that functional divergence in feeding morphology has contributed to the origin and maintenance of cichlid species diversity. However, definitive evidence for the action of natural selection has been missing. Here we use quantitative genetics to identify regions of the cichlid genome responsible for functionally important shape differences in the oral jaw apparatus. The consistent direction of effects for individual quantitative trait loci suggest that cichlid jaws and teeth evolved in response to strong, divergent selection. Moreover, several chromosomal regions contain a disproportionate number of quantitative trait loci, indicating a prominent role for pleiotropy or genetic linkage in the divergence of this character complex. Of particular interest are genomic intervals with concerted effects on both the length and height of the lower jaw. Coordinated changes in this area of the oral jaw apparatus are predicted to have direct consequences for the speed and strength of jaw movement. Taken together, our results imply that the rapid and replicative nature of cichlid trophic evolution is the result of directional selection on chromosomal packages that encode functionally linked aspects of the craniofacial skeleton.

Variations in rest vertical dimension: effects of standing posture in edentulous patients.

Science.gov (United States)

Makzoume, Joseph E

2007-01-01

The orientation of a patient's head changes, depending on whether he or she is sitting or standing in a relaxed upright position. An edentulous patient's vertical dimension at rest may show variations that can result in an inaccurate determination of his or her occlusal vertical dimension. This study recorded the rest vertical dimension (RVD) established among 60 totally edentulous subjects who were standing in the position of greatest comfort (self-balance position) and compared it with the patients' RVD when they were seated in a relaxed upright position, with the Frankfort Plane parallel to the horizontal. The RVD was measured (in mm) between two dots located on the midline of the face. Two measurements were made: one when the patient was seated upright and relaxed (with the Frankfort Plane parallel to the horizontal) with no head support, and the other when the patient was standing relaxed on both feet in a self-balance position. Five alternated measurements were made for each subject in each position. A mean RVD was calculated for each subject in each body posture and the mean values from both positions were compared. Statistical analysis was performed using Student's t-test (alpha = 0.05). No significant differences were noted between the RVD of the seated and standing positions (P = 0.67).

Local anaesthesia in the upper jaw

NARCIS (Netherlands)

Baart, J.A.; Baart, J.A.; Brand, H.S.

2017-01-01

The sensory innervation of the upper jaw arises from the second trunk of the trigeminal nerve, the maxillary nerve. This main branch of the trigeminal nerve leaves the neurocranium via the foramen rotundum, reaches the pterygopalatine fossa and runs straight through the infraorbital nerve, branching

Radiographic features of large cystic lesions of the jaws in children

International Nuclear Information System (INIS)

Bodner, Lipa; Woldenberg, Yitzhak; Bar-Ziv, Jacob

2003-01-01

The surgical approach to cystic lesions of the jaws is either marsupialisation or enucleation. The treatment of choice is dependent on the size of the lesion, the bony integrity of the cyst and its proximity to anatomical structures.Objectives. To assess large (>2.0 cm) cystic lesions of the jaws using plain film radiography (PFR), CT, multiplanar reconstruction program (MPR) and three-dimensional CT (3D-CT).Patients and methods. Twelve children aged 7-14 years.Results. The classic radiological feature was a unilocular radiolucent area surrounded by a well-defined radio-opaque margin adjacent to the root of a non-viable tooth or associated with the crown of an unerupted tooth. Malposition of teeth and root resorption were more common in dentigerous cysts. The features seen on CT were clear and more precise than those seen on PFR. MPR, by the three-dimensional visualisation of the jaw (axial, panoramic, and bucco-lingual), provided useful information for determining the outline of the cyst and its proximity to adjacent anatomical structures, such as teeth, nerves or maxillary sinus. 3-D CT further and more clearly demonstrated discontinuity in the buccal or palatal/lingual cortices of the jaw bone. PFR was very accurate in determining root resorption.Conclusions. CT with MPR and, ideally, 3-D CT should be used for the comprehensive diagnostic work-up and meticulous surgical management of large cystic lesions of the jaws in children. (orig.)

Analyzing surface EMG signals to determine relationship between jaw imbalance and arm strength loss

Directory of Open Access Journals (Sweden)

Truong Quang Dang Khoa

2012-08-01

Full Text Available Abstract Background This study investigated the relationship between dental occlusion and arm strength; in particular, the imbalance in the jaw can cause loss in arm strength phenomenon. One of the goals of this study was to record the maximum forces that the subjects can resist against the pull-down force on their hands while biting a spacer of adjustable height on the right or left side of the jaw. Then EMG measurement was used to determine the EMG-Force relationship of the jaw, neck and arms muscles. This gave us useful insights on the arms strength loss due to the biomechanical effects of the imbalance in the jaw mechanism. Methods In this study to determine the effects of the imbalance in the jaw to the strength of the arms, we conducted experiments with a pool of 20 healthy subjects of both genders. The subjects were asked to resist a pull down force applied on the contralateral arm while biting on a firm spacer using one side of the jaw. Four different muscles – masseter muscles, deltoid muscles, bicep muscles and trapezoid muscles – were involved. Integrated EMG (iEMG and Higuchi fractal dimension (HFD were used to analyze the EMG signals. Results The results showed that (1 Imbalance in the jaw causes loss of arm strength contra-laterally; (2 The loss is approximately a linear function of the height of the spacers. Moreover, the iEMG showed the intensity of muscle activities decreased when the degrees of jaw imbalance increased (spacer thickness increased. In addition, the tendency of Higuchi fractal dimension decreased for all muscles. Conclusions This finding indicates that muscle fatigue and the decrease in muscle contraction level leads to the loss of arm strength.

An investigation on the frequency of partial prosthesis classification in dental faculty, Shiraz University of Medical Sciences

Directory of Open Access Journals (Sweden)

Zand S

2002-06-01

Full Text Available Tooth loss is a kind of handicap and losing a number of teeth makes an individual susceptible to this disability. Having knowledge about the prevalence of partial tooth loss, provides us with a better understanding of social hygiene. On the other hand, having access to such an information, students can be led properly to treat more prevalent cases. The goal of this retrospective study is to investigate the frequency of partial prosthesis classifications, among patients, referred to Shiraz dental faculty. Sexuality, tooth loss classification and its reason and the presence of additional space were studied about all patients (371 females, 205 males from (97-98 to the end of (99-2000. The results showed that females were more than males (64.4%, the lower jaw was treated more than the upper jaw (67.9%, dental caries were the most important reason for extraction (55.5%, class I among females (28.79% and class II mod I among males (29.73% had the most frequency, meaning that the most cases were free end, so more attention should be paid for the education of free end partial prosthesis, however, preventive steps should be taken to retain abutment teeth.

Potential risk factors for jaw osteoradionecrosis after radiotherapy for head and neck cancer

International Nuclear Information System (INIS)

Kuhnt, Thomas; Stang, Andreas; Wienke, Andreas; Vordermark, Dirk; Schweyen, Ramona; Hey, Jeremias

2016-01-01

To identify potential risk factors for the development of jaw osteoradionecrosis (ORN) after 3D-conformal radiotherapy (3D-CRT) and intensity-modulated radiotherapy (IMRT) among patients with newly diagnosed head and neck cancer. This study included 776 patients who underwent 3D-CRT or IMRT for head and neck cancer at the Department of Radiotherapy at the University Hospital Halle-Wittenberg between 2003 and 2013. Sex, dental status prior to radiotherapy, tumor site, bone surgery during tumor resection, concomitant chemotherapy, and the development of advanced ORN were documented for each patient. ORN was classified as grade 3, 4, or 5 according to the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer classification or grade 3 or 4 according to the late effects in normal tissues/subjective, objective, management, and analytic scale. The cumulative incidence of ORN was estimated. Cox regression analysis was used to identify prognostic risk factors for the development of ORN. Fifty-one patients developed advanced ORN (relative frequency 6.6 %, cumulative incidence 12.4 %). The highest risk was found in patients who had undergone primary bone surgery during tumor resection (hazard ratio [HR] = 5.87; 95 % confidence interval [CI]: 3.09–11.19) and in patients with tumors located in the oral cavity (HR = 4.69; 95 % CI: 1.33–16.52). Sex, dentition (dentulous vs. edentulous), and chemotherapy had no clinically relevant influence. In contrast to most previous studies, we noted a low cumulative incidence of advanced ORN. Patients with tumors located in the oral cavity and those who undergo bone surgery during tumor resection prior to RT may be considered a high-risk group for the development of ORN

Extensive jaw mobility in suckermouth armored catfishes (Loricariidae): a morphological and kinematic analysis of substrate scraping mode of feeding.

Science.gov (United States)

Adriaens, Dominique; Geerinckx, Tom; Vlassenbroeck, Jelle; Van Hoorebeke, Luc; Herrel, Anthony

2009-01-01

Loricariidae, or suckermouth armored catfishes, possess upper and lower jaws that are ventrally oriented and that bear teeth that touch the substrate from which algae and other food items are scraped. The ventral orientation and the highly specialized morphology of the jaws, characterized by protrusible upper jaws and left-right decoupled lower jaws, are observed in Pterygoplichthys disjunctivus, the species investigated here. Kinematic data of the scraping feeding movements, obtained by external high-speed and x-ray recordings, are used to quantify jaw movement, especially to test for upper jaw mobility and versatility during substrate scraping. Our results show that the mobility of the jaws is indeed high compared with what is standard for catfishes. The upper jaw's ability to perform a substantial degree of rostrocaudal movement is quite unique for catfishes. The ventromedially oriented lower jaws, with the teeth and the coronoid process at opposite sides, display an extensive mobility: they rotate around the suspensorial articulation and around their longitudinal axis, resulting in an extended scraping movement and thereby covering a large surface area. The lower jaws also show a left-right asymmetry in their movements during scraping. Thus, our results suggest that the extreme morphological specializations of the jaws in loricariid catfishes are linked to an increased mobility and functional versatility, allowing these animals to efficiently scrape algae from substrates with irregular surfaces.

Regulation of eye and jaw colouration in three-spined stickleback Gasterosteus aculeatus.

Science.gov (United States)

Franco-Belussi, L; De Oliveira, C; Sköld, H N

2018-03-25

Fish can change their skin and eye colour for background matching and signalling. Males of Gasterosteus aculeatus develop ornamental blue eyes and a red jaw during the reproductive season, colours that are further enhanced during courtship. Here, the effects of different hormones on physiological colour changes in the eyes and jaws of male and female G. aculeatus were investigated in vitro. In an in vivo experiment, G. aculeatus were injected with a receptor blocker of a pivotal hormone (noradrenaline) that controls colour change. In males, noradrenaline had aggregating effects on melanophore and erythrophore pigments resulting in blue eyes and a pale jaw, whereas melanocyte-concentrating hormone (MCH) and melatonin resulted in a pale jaw only. When noradrenalin was combined with melanocyte stimulating hormone (MSH) or prolactin, the jaw became red, while the eyes remained blue. In vivo injection of yohimbine, an alpha-2 adrenoreceptor blocker, resulted in dispersion of melanophore pigment in the eyes and inhibited the blue colouration. Altogether, the data suggest that noradrenalin has a pivotal role in the short-term enhancement of the ornamental colouration of male G. aculeatus, potentially together with MSH or prolactin. This study also found a sex difference in the response to MCH, prolactin and melatonin, which may result from different appearance strategies in males, versus the more cryptic females. © 2018 The Fisheries Society of the British Isles.

Bisphosphonates and osteonecrosis of the jaw.

Science.gov (United States)

Shannon, Jodi; Shannon, John; Modelevsky, Steven; Grippo, Anne A

2011-12-01

Bisphosphonates are used worldwide as a successful treatment for people with osteoporosis, which is the major underlying cause of fractures in postmenopausal women and older adults. These agents are successful at increasing bone mass and bone trabecular thickness, decreasing the risk of fracture, and decreasing bone pain, enabling individuals to have better quality of life. Bisphosphonates are also used to treat multiple myeloma, bone metastasis, and Paget's disease; however, bisphosphonate treatment may result in negative side effects, including osteonecrosis of the jaw (ONJ). ONJ involves necrotic, exposed bone in the jaw, pain, possible secondary infection, swelling, painful lesions, and various dysesthesias, although less-severe cases may be asymptomatic. First-generation bisphosphonates, which do not contain nitrogen, are metabolized into a nonfunctional, cytotoxic analogue of adenosine triphosphate and cause osteoclast death by starvation. Second-generation bisphosphonates are nitrogen-containing agents; these inhibit osteoclast vesicular trafficking, membrane ruffling, morphology, and cytoskeletal arrangement by inhibiting farnesyl diphosphate synthase in the mevalonate pathway. Physicians treating older adults with osteoporosis and cancer should work together with dental practitioners, pharmacists, and other clinicians to inform individuals receiving bisphosphonates of their possible side effects and to suggest precautionary steps that may minimize the risk of osteonecrosis, particularly of the jaw. These include practicing good oral hygiene; scheduling regular dental examinations and cleanings; and cautioning people who are scheduling treatment for periodontal disease, oral and maxillofacial therapy, endodontics, implant placement, restorative dentistry, and prosthodontics. Recommendations for management of people with ONJ include an oral rinse, such as chlorhexidine, and antibiotics. © 2011, Copyright the Authors Journal compilation © 2011, The American

Immediate occlusal loading of implants in the partially edentate mandible: a prospective 1-year radiographic and 4-year clinical study.

Science.gov (United States)

Ostman, Pär-Olov; Hellman, Mats; Sennerby, Lars

2008-01-01

The purpose of the present prospective clinical study was to evaluate the radiographic and clinical outcome of immediately loaded implants in the partial edentulous mandible over a 4-year follow-up period using a modified surgical protocol, primary implant stability criteria, and splinting for inclusion. Patients in need of implant treatment in the partial edentate mandible were consecutively included in the study. The implant sites were underprepared to obtain maximal stability. Inclusion criteria for the study were torque of a least 30 Ncm before final seating of the implant and an ISQ greater than 60. A provisional fixed partial denture was delivered within 24 hours and a definitive fixed partial denture within 3 months. The patients were monitored with clinical and radiographic follow-up examinations for up to 4 years. Stability of the implants was measured with resonance frequency analysis at placement and after 6 months. Ninety-six patients were evaluated, and 77 patients who met the inclusion criteria were included. A total of 111 fixed partial dentures supported by 257 Brånemark System implants (77 turned and 180 TiUnite implants) were delivered. Four (1.6%) of the 257 implants did not osseointegrate, giving an overall survival rate of 98.4% after 4 years. Three turned (3.9%) implants and 1 oxidized implant (0.6%) failed after 4 to 13 months. The average marginal bone resorption was 0.7 mm (SD 0.78) during the first year in function. Turned implants showed an average bone loss of 0.5 mm (SD 0.8) and oxidized implants an average of 0.7 mm (SD 0.8). Resonance frequency analysis showed a mean implant stability quotient of 72.2 (SD 7.5) at placement and 72.5 (SD 5.7) after 6 months of loading. It is concluded that immediate loading of implants with firm primary stability in partially edentulous areas of the mandible appears to be a viable procedure with predictable outcome.

New look at the anatomy of the jaws by dental CT imaging

International Nuclear Information System (INIS)

Nikolov, V.

2006-01-01

Full text: We represent a part of a retrospective study of CT findings of the jaws and teeth's by Dental CT. For preoperative planning in dental implantology, 215 jaws of 169 patients was investigated. There have been established the reasons for the lost of teeth's, the exact anatomical situation, the height and the vestibular-lingual thickness of the alveolar crest, the thickness of the cortical bone, the presence and volume of the bone defects, the bone mineral density in the implantation zone. A try has been made to create a mathematic model for calculating the risk of failed osseointegration. The investigating of jaws and teeth by Dental CT made it possible to find and localize excessive vascular canals in the frontal parts of the mandible, which is important to prevent complications in operative insertion of implants. There is a high percentage of patients with a great vestibular cortical resorption in the incisive and premolar region of both jaws. The existence of such similar situation in younger patients without periodontal disease

Central xanthoma of the jaw in association with Noonan syndrome.

Science.gov (United States)

Olson, Nicholas J; Addante, Rocco R; de Abreu, Francine B; Memoli, Vincent A

2018-05-01

Xanthomas are histiocytic lesions of the skin, soft tissue and bone and are generally considered to be reactive in nature. When they arise in the bones of the jaw, they are referred to as central xanthomas. New evidence supports the hypothesis that central xanthomas are a separate and distinct entity from their extragnathic counterparts. Noonan syndrome (NS) is an autosomal dominant disorder that has been associated with giant cell lesions which also commonly occur in the jaw. We present a case of a 15year-old-male with NS who presented with a radiolucent lesion of the mandible that on excision, was found to be a central xanthoma. Although giant cell lesions have been well described in NS, xanthomas of the jaw have not been reported. We will also discuss the entities that must be excluded prior to making a diagnosis of central xanthoma, as this can affect both treatment and follow up. Copyright © 2018. Published by Elsevier Inc.

Prevalence Of Maxillary Sinus Jaw Mucuous Cysts In University Dental Radiology Service

Directory of Open Access Journals (Sweden)

Joaquim Lira Saraiva Neto

2017-07-01

Full Text Available Background: Mucosal cyst of the maxillary sinus or antral pseudocyst is one of great importance injury, being the pathology that affects more the maxillary sinus. Their discovery, in most cases, it is for the interpretation of the images in routine panoramic radiography. Aims: The research aimed to evaluate the prevalence of mucous cyst in maxillary sinus in radiology clinic at Ceara Federal University. Material and Methods: To this study conduction, were analyzed 1996 panoramic radiographs from a digital file obtained between April 2011 to April 2013 Results:. Aspects as gender, affected side and teeth absence next to the cyst in the respective quadrant were evaluated.It was observed in the sample the occurrence of 45 patients with suggested images of mucous cysts in maxillary sinus,making a prevalence of 2,25%. From them, 26 (57,8%were female and 19 (42,2% were male. 48 maxillary sinuswere affected with the wound, from which28 (58,3% it was in the left side and 20 (41,7% in the right site. Three patients presented the wound in both sides, what represents 6,7% of the affected patients. From those 48 Mucous retention cyst, 40 (83,3% were not related to an edentulous area in ipsilateral quadrant and 8 (16,7% were shown next to an edentulous area. Conclusion: The conclusion was that the cyst of retention mucous in the maxillary sinus had prevalence in males and in the left side of the maxillary sinus. It was not found a relation between the cyst and the edentulous area.

Minimally invasive piezosurgery for a safe placement of blade dental implants in jaws with severe bone loss

Directory of Open Access Journals (Sweden)

F. Rossi

2014-10-01

Full Text Available Aim :Severe atrophies of edentulous jaws require major reconstructive bone surgery in order to allow the placement of root-form implants with standard diameter. These bone augmentation techniques represent the best option reported in the literature, but they are often rejected by patients because of their high economic and biological costs in addition to the possibility of failure in the short and/or long term. In the maxilla regenerative methods (onlay, inlay, and distraction have high success rates, whereas in the mandible, especially in the distal atrophic area, they are not so predictable. In such situations an alternative technique for fixed prosthethic rebilitation is the insertion of platform blade implants, which have their elective indication for atrophic bone ridges with reduced width, owing to their reduced thickness. The aim of this study is to assess the effectiveness of the use of piezoelectric ultrasonic handpieces, in order to simplify the placement of blade implants, making it safer and less traumatic than with conventional surgical procedures. Materials and methods: Platform blade implants are extension implant functionally and aesthetically reliable, even if they require a more difficult surgical technique compared with the one currently in use for screw implants. A minimally invasive procedure by means of piezosurgery that was performed on 142 subjects is presented and a case is reported which highlights the successful results. Results: and conclusion The use of piezoelectric ultrasonic handpieces simplifies the surgical procedure for the placement of blade implant, making it safer and less traumatic.

Computer tomography valorization of the vascular lingual channels in the jaw

International Nuclear Information System (INIS)

Costantino, Sebastian; Capiel, Carlos h; Bouzas, Carlos; Vuotto, Miguel; Ferrari, Daniela; Bazzano, Sebastian

2006-01-01

Purpose: To determine the frequency, location and position of vascular lingual channels of jaw by dental CT and classifying them based on its location. Material and methods: Dental CT of 100 consecutive patients were reevaluated as previous evaluation to the positioning of dental implants. They are classified by linking their location on the jaw with the number of tooth present or absent in that area. Results: All patients had at least one lingual vascular channel in the jaw; 36 patients presented two channels, eight patients presented three and a patient presented four. The more frequent location was between the sectors of the pieces 31 and 41. Sixteen patients showed two channels (superior and inferior) in that location. The second location by frequency was between pieces 32 and 33 (nine patients). The average distance between the lingual surface of the alveolar rim and the vascular channels was of 16 mm. Conclusion: the dental CT is an excellent method for the identification of the vascular lingual channels by its multiplanar capacity and appropriate image resolution. The characterization and classification of these conduits by a method of easy reading for the radiologists and the dentists assure a correct pre surgical valuation avoiding hemorrhages during the jaw perforation in the positioning of dental implants. (author) [es

Failure analysis of vise jaw holders for hacksaw machine

Directory of Open Access Journals (Sweden)

Essam Ali Al-Bahkali

2018-01-01

Full Text Available Failure analysis in mechanical components has been investigated in many studies in the last few years. Failure analysis and prevention are important functions in all engineering disciplines. Materials engineers are often the lead role in the analysis of failures, where a component or product fails in service or if a failure occurs during manufacturing or production processing. In any case, one must determine the cause of the failure to prevent future occurrences and/or to improve the performance of the device, component or structure. For example, the vise jaw holders of hacksaws can break due to accidental heavy loads or machine misuse. The parts that break are the stationary and movable vise jaw holders and the connecter power screw between the holders. To investigate the failure of these components, a three-dimensional finite element model for stress analysis was performed. First, the analysis identified the broken components of the hacksaw machine. In addition, the type of materials of the broken parts was identified, a CAD model was built, and the hacksaw mechanism was analyzed to determine the accurate applied loads on the broken parts. After analyzing the model using Abaqus CAE software, the results showed that the location of the high stresses was identical with the high-stress locations in the original, broken parts. Furthermore, the power screw was subjected to a high load, which deformed the power screw. Also, the stationary vise jaw holder was broken by impact because it was not touched by the power screw until the movable vise jaw holder broke. A conclusion is drawn from the failure analysis and a way to improve the design of the broken parts is suggested.

Bisphosphonate-associated osteonecrosis of the jaws

Directory of Open Access Journals (Sweden)

Pankaj Agarwal

2012-01-01

Full Text Available Bisphosphonates constitute a group of drugs capable of modulating bone turnover and reduce its remodeling when an excessive resorption occurs. This is why they are indicated in a large group of bone diseases like postmenopausal osteoporosis or osteolysis associated with breast cancer or multiple myeloma. Over the last few years and due to their extensive use, many cases of complications associated with their use have been published. Among the most important possible adverse effects are the oral ones, with the appearance of ulcerations and, especially, osteonecrosis of the jaws associated with this therapy. In this paper, we have analyzed the general characteristics of these drugs and their mechanisms of action as well as the described adverse effects, especially oral and maxillofacial, have been made special reference, regarding the prevention of osteonecrosis of the jaws, heightened by cases described in the medical and odontological literature. The preventive protocol backs up the fundamental role of the odontologist in the effective prevention of this process before, during and after the treatment.

Osteosarcoma: a comparison of jaw versus nonjaw localizations and review of the literature

NARCIS (Netherlands)

van den Berg, H.; Schreuder, W.H.; de Lange, J.

2013-01-01

Purpose. It is assumed that osteosarcomas of the jaws mainly occur at older ages, whereas the most prominent sites, that is, the long bones, are more affected at ages <20. Jaw-localized tumors are less malignant and have lower metastatic spread rates. Patients and Methods. This study analyses the

Osteosarcoma: A Comparison of Jaw versus Nonjaw Localizations and Review of the Literature

NARCIS (Netherlands)

van den Berg, H.; Schreuder, W. H.; de Lange, J.

2013-01-01

Purpose. It is assumed that osteosarcomas of the jaws mainly occur at older ages, whereas the most prominent sites, that is, the long bones, are more affected at ages <20. Jaw-localized tumors are less malignant and have lower metastatic spread rates. Patients and Methods. This study analyses the

Beam feasibility study of a collimator with in-jaw beam position monitors

Science.gov (United States)

Wollmann, Daniel; Nosych, Andriy A.; Valentino, Gianluca; Aberle, Oliver; Aßmann, Ralph W.; Bertarelli, Alessandro; Boccard, Christian; Bruce, Roderik; Burkart, Florian; Calvo, Eva; Cauchi, Marija; Dallocchio, Alessandro; Deboy, Daniel; Gasior, Marek; Jones, Rhodri; Kain, Verena; Lari, Luisella; Redaelli, Stefano; Rossi, Adriana

2014-12-01

At present, the beam-based alignment of the LHC collimators is performed by touching the beam halo with both jaws of each collimator. This method requires dedicated fills at low intensities that are done infrequently and makes this procedure time consuming. This limits the operational flexibility, in particular in the case of changes of optics and orbit configuration in the experimental regions. The performance of the LHC collimation system relies on the machine reproducibility and regular loss maps to validate the settings of the collimator jaws. To overcome these limitations and to allow a continuous monitoring of the beam position at the collimators, a design with jaw-integrated Beam Position Monitors (BPMs) was proposed and successfully tested with a prototype (mock-up) collimator in the CERN SPS. Extensive beam experiments allowed to determine the achievable accuracy of the jaw alignment for single and multi-turn operation. In this paper, the results of these experiments are discussed. The non-linear response of the BPMs is compared to the predictions from electromagnetic simulations. Finally, the measured alignment accuracy is compared to the one achieved with the present collimators in the LHC.

Non-radiation related osteonecrosis of the jaws in dogs: 14 cases (1996 - 2014

Directory of Open Access Journals (Sweden)

Santiago ePeralta

2015-05-01

Full Text Available Osteonecrosis of the jaws is an entity of major clinical impact characterized by chronically exposed necrotic mandibular or maxillary bone. Its clinicopathological characteristics and possible inciting or risk factors are well described in humans but only anecdotally reported in dogs. Treatment modalities and outcome vary depending on the inciting factors involved and the extent and severity of the lesions. The objectives of this study were to retrospectively describe the clinicopathological features of non-radiation related osteonecrosis of the jaws in a series of 14 dogs, identify possible inciting or risk factors, and report on the surgical treatment and outcome. For all patients, the medical records were used to collect information regarding signalment, clinical signs, characteristics of the oral, jaw and dental lesions, diagnostic imaging findings, histopathological and microbiological analysis, treatment performed and outcome. The data collected showed that non-radiation related osteonecrosis of the jaws appears to be an infrequent clinical entity but of significant impact in dogs; that a history of systemic antibiotics and dental disease is common among affected dogs; that previous dental extractions are commonly associated with ONJ sites; that using a systematic diagnostic approach is essential for diagnosis; and that thorough surgical débridement combined with a course of oral antibiotics was effective in the described dogs affected by advanced non-radiation related osteonecrosis of the jaws.

Jaw muscle fiber type distribution in Hawaiian gobioid stream fishes: histochemical correlations with feeding ecology and behavior.

Science.gov (United States)

Maie, Takashi; Meister, Andrew B; Leonard, Gerald L; Schrank, Gordon D; Blob, Richard W; Schoenfuss, Heiko L

2011-12-01

Differences in fiber type distribution in the axial muscles of Hawaiian gobioid stream fishes have previously been linked to differences in locomotor performance, behavior, and diet across species. Using ATPase assays, we examined fiber types of the jaw opening sternohyoideus muscle across five species, as well as fiber types of three jaw closing muscles (adductor mandibulae A1, A2, and A3). The jaw muscles of some species of Hawaiian stream gobies contained substantial red fiber components. Some jaw muscles always had greater proportions of white muscle fibers than other jaw muscles, independent of species. In addition, comparing across species, the dietary generalists (Awaous guamensis and Stenogobius hawaiiensis) had a lower proportion of white muscle fibers in all jaw muscles than the dietary specialists (Lentipes concolor, Sicyopterus stimpsoni, and Eleotris sandwicensis). Among Hawaiian stream gobies, generalist diets may favor a wider range of muscle performance, provided by a mix of white and red muscle fibers, than is typical of dietary specialists, which may have a higher proportion of fast-twitch white fibers in jaw muscles to help meet the demands of rapid predatory strikes or feeding in fast-flowing habitats. Copyright © 2011 Elsevier GmbH. All rights reserved.

Jaw lesions associated with impacted tooth: A radiographic diagnostic guide

Energy Technology Data Exchange (ETDEWEB)

Motazavi, Hamed; Bharvand, Maryam [Dept. of Oral Medicine, School of Dentistry, Shahid Beheshti University of Medical Sciences, Tehran (Iran, Islamic Republic of)

2016-09-15

This review article aimed to introduce a category of jaw lesions associated with impacted tooth. General search engines and specialized databases such as Google Scholar, PubMed, PubMed Central, MedLine Plus, Science Direct, Scopus, and well-recognized textbooks were used to find relevant studies using keywords such as 'jaw lesion', 'jaw disease', 'impacted tooth', and 'unerupted tooth'. More than 250 articles were found, of which approximately 80 were broadly relevant to the topic. We ultimately included 47 articles that were closely related to the topic of interest. When the relevant data were compiled, the following 10 lesions were identified as having a relationship with impacted tooth: dentigerous cysts, calcifying odontogenic cysts, unicystic (mural) ameloblastomas, ameloblastomas, ameloblastic fibromas, adenomatoid odontogenic tumors, keratocystic odontogenic tumors, calcifying epithelial odontogenic tumors, ameloblastic fibro-odontomas, and odontomas. When clinicians encounter a lesion associated with an impacted tooth, they should first consider these entities in the differential diagnosis. This will help dental practitioners make more accurate diagnoses and develop better treatment plans based on patients' radiographs.

Jaw lesions associated with impacted tooth: A radiographic diagnostic guide

International Nuclear Information System (INIS)

Motazavi, Hamed; Bharvand, Maryam

2016-01-01

This review article aimed to introduce a category of jaw lesions associated with impacted tooth. General search engines and specialized databases such as Google Scholar, PubMed, PubMed Central, MedLine Plus, Science Direct, Scopus, and well-recognized textbooks were used to find relevant studies using keywords such as 'jaw lesion', 'jaw disease', 'impacted tooth', and 'unerupted tooth'. More than 250 articles were found, of which approximately 80 were broadly relevant to the topic. We ultimately included 47 articles that were closely related to the topic of interest. When the relevant data were compiled, the following 10 lesions were identified as having a relationship with impacted tooth: dentigerous cysts, calcifying odontogenic cysts, unicystic (mural) ameloblastomas, ameloblastomas, ameloblastic fibromas, adenomatoid odontogenic tumors, keratocystic odontogenic tumors, calcifying epithelial odontogenic tumors, ameloblastic fibro-odontomas, and odontomas. When clinicians encounter a lesion associated with an impacted tooth, they should first consider these entities in the differential diagnosis. This will help dental practitioners make more accurate diagnoses and develop better treatment plans based on patients' radiographs

A comparison of cephalometric analyses for assessing sagittal jaw relationship

International Nuclear Information System (INIS)

Erum, G.; Fida, M.

2008-01-01

To compare the seven methods of cephalometric analysis for assessing sagittal jaw relationship and to determine the level of agreement between them. Seven methods, describing anteroposterior jaw relationships (A-B plane, ANB, Wits, AXB, AF-BF, FABA and Beta angle) were measured on the lateral cephalographs of 85 patients. Correlation analysis, using Cramer's V-test, was performed to determine the possible agreement between the pair of analyses. The mean age of the sample, comprising 35 males and 50 females was 15 years and 3 months. Statistically significant relationships were found among seven sagittal parameters with p-value <0.001. Very strong correlation was found between AXB and AF-BF distance (r=0.924); and weak correlation between ANB and Beta angle (r=0.377). Wits appraisal showed the greatest coefficient of variability. Despite varying strengths of association, statistically significant correlations were found among seven methods for assessing sagittal jaw relationship. FABA and A-B plane may be used to predict the skeletal class in addition to the established ANB angle. (author)

Investigation of Pitch and Jaw Width to Decrease Delivery Time of Helical Tomotherapy Treatments for Head and Neck Cancer

International Nuclear Information System (INIS)

Moldovan, Monica; Fontenot, Jonas D.; Gibbons, John P.; Lee, Tae Kyu; Rosen, Isaac I.; Fields, Robert S.; Hogstrom, Kenneth R.

2011-01-01

Helical tomotherapy plans using a combination of pitch and jaw width settings were developed for 3 patients previously treated for head and neck cancer. Three jaw widths (5, 2.5, and 1 cm) and 4 pitches (0.86, 0.43, 0.287, and 0.215) were used with a (maximum) modulation factor setting of 4. Twelve plans were generated for each patient using an identical optimization procedure (e.g., number of iterations, objective weights, and penalties, etc.), based on recommendations from TomoTherapy (Madison, WI). The plans were compared using isodose plots, dose volume histograms, dose homogeneity indexes, conformity indexes, radiobiological models, and treatment times. Smaller pitches and jaw widths showed better target dose homogeneity and sparing of normal tissue, as expected. However, the treatment time increased inversely proportional to the jaw width, resulting in delivery times of 24 ± 1.9 min for the 1-cm jaw width. Although treatment plans produced with the 2.5-cm jaw were dosimetrically superior to plans produced with the 5-cm jaw, subsequent calculations of tumor control probabilities and normal tissue complication probabilities suggest that these differences may not be radiobiologically meaningful. Because treatment plans produced with the 5-cm jaw can be delivered in approximately half the time of plans produced with the 2.5-cm jaw (5.1 ± 0.6 min vs. 9.5 ± 1.1 min), use of the 5-cm jaw in routine treatment planning may be a viable approach to decreasing treatment delivery times from helical tomotherapy units.

Differences in loading of the temporomandibular joint during opening and closing of the jaw

NARCIS (Netherlands)

Tuijt, M.; Koolstra, J.H.; Lobbezoo, F.; Naeije, M.

2010-01-01

Kinematics of the human masticatory system during opening and closing of the jaw have been reported widely. Evidence has been provided that the opening and closing movement of the jaw differ from one another. However, different approaches of movement registration yield divergent expectations with

Association between edentulism and angina pectoris in Mexican adults aged 35 years and older: a multivariate analysis of a population-based survey.

Science.gov (United States)

Medina-Solís, Carlo Eduardo; Pontigo-Loyola, América Patricia; Pérez-Campos, Eduardo; Hernández-Cruz, Pedro; Ávila-Burgos, Leticia; Kowolik, Michael J; Maupomé, Gerardo

2014-03-01

The possible association between oral infection and chronic inflammation and cardiovascular disease risk has been studied intensively. The present study is designed to determine the strength of association between edentulism and angina pectoris in Mexican adults aged 35 years and older. Using the tools and sampling strategies of the World Health Survey of the World Health Organization, cross-sectional data were collected in Mexico in the National Performance Assessment Survey (probabilistic, multistage, and cluster sampling). Dental information was available for 20 of the 32 states of Mexico. Angina and edentulism are self-reported in this study. Statistical analysis was performed using binary logistic regression adjusting for complex samples. A total of 13,966 participants, representing a population of 29,853,607 individuals, were included. Of the complete study population, 3,052,263 (10.2%) were completely toothless, and 673,810 (2.3%) were diagnosed with angina pectoris. After adjusting for smoking, alcohol consumption, diabetes, body mass index, and sex, the effect of edentulism on angina was modified by age (interaction), being more marked in the younger age group (odds ratio [OR] = exp(2.5597) =12.93) than in the older individuals surveyed (OR = exp(2.5597 + (-0.0334)) =12.51). Additionally, low physical activity (OR = 1.51; 95% confidence interval [CI] = 1.03 to 2.22) and higher socioeconomic status (OR = 1.37; 95% CI = 1.00 to 1.90) were more likely to be associated with angina pectoris. Overall, the results of this study, conducted in a representative sample of Mexican adults, suggest that an association exists between edentulism and angina pectoris. Additional studies are necessary to elucidate the underlying mechanism for this association.

Epidemiology and Risk Factors of Tooth Loss among Iranian Adults: Findings from a Large Community-Based Study

Directory of Open Access Journals (Sweden)

Saber Khazaei

2013-01-01

Full Text Available Objectives. To investigate the prevalence of tooth loss and different prosthetic rehabilitations among Iranian adults, as well as the potential determinants of tooth loss. Methods. In a cross-sectional community-based study conducted among 8094 Iranian adults living in Isfahan province, a self-administered questionnaire was used to assess epidemiologic features of tooth loss. Results. Thirty-two percent of subjects had all their teeth, 58.6% had lost less than 6, and 7.2% of participants had lost more than 6 teeth. One hundred and sixty-nine individuals (2.2% were edentulous. Among participants, 2.3% had single jaw removable partial denture, 3.6% had complete removable denture in both jaws, and 4.6% had fixed prosthesis. Others reported no prosthetic rehabilitation (89.5%. In the age subgroup analysis (≤35 and >35 years old tooth loss was more prevalent among men than women (OR=2.8 and 1.9, resp., P35 years (adjusted OR=1.29, P<0.01. Conclusions. Tooth loss is highly prevalent in Iranian adult population. Community programs promoting oral health for prevention of tooth loss should be considered taking into account its major determinants including lower educational level, male gender, smoking, and metabolic abnormality.

On The Evolution of Human Jaws and Teeth: A Review

Directory of Open Access Journals (Sweden)

Serhat Yalcin

2011-06-01

Full Text Available The jaws and teeth of Homo sapiens have evolved, from the last common ancestor of chimpanzee and men to their current form. Many factors such as the foods eaten and the processing of foods by fire and tools have effected this evolution course. The evolution of the masticatory complex is related to other anatomical features such as brain size and bipedal posture, and leads to important proceedings like the formation of speech and language. In this review, the evolution of human jaws and teeth and its impact on the general course of human evolution is discussed.

Electromagnetic Simulations of an Embedded BPM in Collimator Jaws

CERN Document Server

Boccard, C; Nosych, A

2011-01-01

Next gen­er­a­tion of the LHC col­li­ma­tors will be equipped with but­ton beam po­si­tion mon­i­tors (BPMs) em­bed­ded into the col­li­ma­tor jaws. Such a so­lu­tion will im­prove the ac­cu­ra­cy of the jaw align­ment with respect to the beam and re­duce the beam time nec­es­sary for the collima­tor setup. This paper de­scribes re­sults of elec­tro­mag­net­ic simu­la­tions of the jaw BPMs per­formed with the CST Par­ti­cle Stu­dio suite, aimed at char­ac­ter­i­sa­tion of the BPMs as well as the simulation soft­ware it­self. The re­sults are com­pared to the mea­sure­ments ob­tained with beam on a pro­to­type sys­tem in­stalled in the CERN SPS.

Influence of botulinum toxin on rabbit jaw muscle activity and anatomy.

Science.gov (United States)

Korfage, J A M; Wang, Jeffrey; Lie, S H J T J; Langenbach, Geerling E J

2012-05-01

Muscles can adapt their fiber properties to accommodate to new conditions. We investigated the extent to which a decrease in muscle activation can cause an adaptation of fiber properties in synergistic and antagonistic jaw muscles. Three months after the injection of botulinum toxin type A in one masseter (anterior or posterior) muscle changes in fiber type composition and fiber cross-sectional areas in jaw muscles were studied at the microscopic level. The injected masseter showed a steep increase in myosin type IIX fibers, whereas fast fibers decreased by about 50% in size. Depending on the injection site, both synergistic and antagonistic muscles showed a significant increase in the size of their fast IIA fibers, sometimes combined with an increased number of IIX fibers. Silencing the activity in the masseter not only causes changes in the fibers of the injected muscle but also leads to changes in other jaw muscles. Copyright © 2012 Wiley Periodicals, Inc.

A morphological study of the masseter muscle using magnetic resonance imaging in patients with jaw deformities. Cases demonstrating mandibular deviation

International Nuclear Information System (INIS)

Higashi, Katsuhiko; Goto, Tazuko K.; Kanda, Shigenobu; Shiratsuchi, Yuji; Nakashima, Akihiko; Horinouchi, Yasufumi

2006-01-01

Numerous studies on the cross-sectional area of masticatory muscles, which are correlated to the facial shape, have been reported for normal subjects in previous articles. However to date, there have been no such studies on masseter muscles at jaw-closing and jaw-opening in patients with jaw deformities involving mandibular deviation. The MRI data sets of the masseter muscles at jaw-closing and jaw-opening in 14 female patients with mandibular deviation, who demonstrated a more than 3-mm deviation in the median line in the lower first incisors in comparison to the upper ones, were utilized. The cross-sectional areas from the origin to the insertion at jaw-closing and jaw-opening which were reconstructed perpendicular to the three-dimensional long axis of each masseter muscle, each maximum cross-sectional area (MCSA) and the ratio of the change in MCSA after jaw-opening were analyzed. As a result, a significant difference was observed between the MCSA at jaw-closing and jaw-opening on the same side. However, no difference in MCSA was seen between the deviated and non-deviated side of the mandible. The line chart patterns of the masseter muscles from the origin to the insertion could be classified into four types. Our results suggest that it is important to analyze cross-sectional areas of the masseter muscles in each subject while considering the three-dimensional axis of each muscle. (author)

The relationship between jaw-opening force and the cross-sectional area of the suprahyoid muscles in healthy elderly.

Science.gov (United States)

Kajisa, E; Tohara, H; Nakane, A; Wakasugi, Y; Hara, K; Yamaguchi, K; Yoshimi, K; Minakuchi, S

2018-03-01

We conducted a clinical cross-sectional study to examine the relationship between jaw-opening force and the cross-sectional area of the suprahyoid muscles and whole skeletal muscle mass. Subjects were healthy 39 males and 51 females without dysphagia and sarcopenia, aged 65 years and older. Jaw-opening force was measured three times using a jaw-opening sthenometer; the maximum of these three was taken as the measurement value. The cross-sectional area of the geniohyoid and anterior belly of the digastric muscles were evaluated using ultrasonography. The skeletal muscle mass index, gait speed and grip strength were evaluated according to the diagnostic criteria of the Asian Working Group for Sarcopenia. For each sex, a multiple regression analysis determined the factors that affect jaw-opening force. Jaw-opening force was associated with the cross-sectional area of the geniohyoid muscle in males (regression coefficient [β] = 0.441, 95% confidence interval [CI] = 14.28-56.09) and females (β = 0.28, 95% CI = 3.10-54.57). Furthermore, in females only, jaw-opening force was associated with the skeletal muscle mass index (β = 0.40, 95% CI = 3.67-17.81). In contrast, jaw-opening force was not associated with the cross-sectional area of the anterior belly of the digastric muscle in either sex. In healthy elderly males and females, jaw-opening force was positively associated with the cross-sectional area of the geniohyoid muscle. However, the jaw-opening force was positively associated with the skeletal muscle mass index only in females. © 2017 John Wiley & Sons Ltd.

Frequency Distribution of Edentulous Posterior Mandibular Ridge Types using Cone Beam Computed Tomography in an Iranian Population

Directory of Open Access Journals (Sweden)

2016-07-01

Full Text Available Introduction: The existing bone is regarded as an important criteria in dental implants. In this regard, the radiographic modality is of great significance in quantifying the remaining bone, and CBCT accurately represents height and width of the existing bone. Therefore, this study aimed to evaluate the frequency distribution of the edentulous posterior mandibular ridge types using cone beam computed tomography in an Iranian population. Methods: In this cross-sectional descriptive study, CBCT scans of 127 patients with full edentulous mandible with an average age of 61.15 were evaluated who referred to a radiology clinic in Tehran. The images were analyzed applying OnDemand3D application and bone height and width of each area were determined. To analyze the collected data, SPSS software (ver,17 was employed applying Fisher's exact test. Results: The ridges were classified in 4 different groups (A,B+,B-w,C-w. The frequency of ridge types A and B + in male and ridge types B-w and C-w in females were demonstrated to be higher. An increase in age led to a reduction in the frequency of type A and a rise in the frequency of type C-w. The mean bone height was higher in males in all areas. In addition, the mean bone width was higher in males in all areas except for the first molar area. Conclusions:  The study results indicated that as the age increases, the height of edentulous mandible reduces, while no significant relationship was detected between the bone width and aging. As a result, with aging the evolution of bone was held to be from type A to type C-W.

Surgiplanner: a new method for one step oral rehabilitation of severe atrophic maxilla.

Science.gov (United States)

Busato, A; Vismara, V; Grecchi, F; Grecchi, E; Lauritano, D

2017-01-01

The implant-prosthetic rehabilitation of edentulous upper jaws has always been complex for surgeons and dentists. The lack of bone in both vertical and horizontal dimension does not allow the correct insertion of dental implants. In addition, patients with edentulous upper and lower arch have a loss of vertical dimension of the face and an aged expression. Many surgical techniques have been proposed to increase the bone volume, height and thickness, such as the Le Fort I osteotomy, the bone grafts and the placement of dental implants. Planning these surgical procedures is difficult, because it is not possible to reproduce the movements of osteotomized bone segments in three planes of space. This article describes the treatment of severe atrophy maxilla with a new approach using a new instrument named "Surgiplanner". Surgiplanner is a method that, only using a computerized axial tomography (CAT), allows to obtain a totally predetermined therapeutic result from both an aesthetic and functional point of view, with surgery of severe resorbed jaws. Surgiplanner allows repositioning of segment of the skeleton of the patient's face in a predetermined and controlled way for the best implant-supported oral rehabilitation.

Treatment of hemimandibular paresthesia in a patient with bisphosphonate-related osteonecrosis of the jaw (BRONJ) by combining surgical resection and PRGF-Endoret.

Science.gov (United States)

Anitua, E; Begoña, L; Orive, G

2013-12-01

We report a case of a 50-year-old patient with bisphosphonate-related osteonecrosis of the jaws (BRONJs) whose symptoms included severe pain and hemimandibular paraesthesia. The treatment included resection of necrotic bone and the application of plasma rich in growth factors (PRGF(®)-Endoret(®)). We closed the ulcer in the soft tissue and her pain and paraesthesia improved. One year postoperatively sensitivity was totally recovered, pain was absent and bone was partially regenerated. Copyright © 2012 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

Analysis of feeding function and jaw stability in bedridden elderly.

Science.gov (United States)

Tamura, Fumiyo; Mizukami, Miki; Ayano, Rika; Mukai, Yoshiharu

2002-01-01

The purpose of this study was to analyze the relationship between jaw stability and the feeding function of 53 bedridden elderly dysphagic patients. Investigations included a questionnaire on daily life activities and meals, oral examinations, functional tests for feeding ability, and assessments of feeding function during the meal. The results of intraoral examination of this patient population for jaw stability revealed that 34.0% of individuals had posterior support for occlusion regardless of whether they had natural teeth or dentures. Thus, the number classified as having mandibular stability (ST) was 18 and that with no mandibular stability (NST) was 35. In a Repetitive Saliva Swallowing Test (RSST), 83.3% of the NST group and 40.0% of the ST group were unable to swallow more than 3 times within 30 seconds. In a water swallowing test, 91.4% of the NST of group was unable to swallow 15 mL of water by a single swallow, while 40.0% of ST group was capable. The results suggest that jaw stabilization by occlusion with the posterior teeth or dental prosthetics is important to feeding function, particularly swallowing.

Implant loading protocols for edentulous patients with fixed prostheses: a systematic review and meta-analysis.

Science.gov (United States)

Papaspyridakos, Panos; Chen, Chun-Jung; Chuang, Sung-Kiang; Weber, Hans-Peter

2014-01-01

To report on the effect of immediate implant loading with fixed prostheses compared to early and conventional loading on implant and prosthesis survival, failure, and complications. An electronic and manual search was conducted to identify randomized controlled clinical trials (RCTs) as well as prospective and retrospective studies involving rough surface implants and implant fixed complete dental prostheses for edentulous patients. The 62 studies that fulfilled the inclusion criteria featured 4 RCTs, 2 prospective case-control studies, 34 prospective cohort studies, and 22 retrospective cohort studies. These studies yielded data from 2,695 patients (2,757 edentulous arches) with 13,653 implants. Studies were grouped according to the loading protocol applied; 45 studies reported on immediate loading, 8 on early loading, and 11 on conventional loading. For the immediate loading protocol with flap surgery, the implant and prosthesis survival rates ranged from 90.1% to 100% and 93.75% to 100%, respectively (range of follow-up, 1 to 10 years). When immediate loading was combined with guided flapless implant placement, the implant survival rates ranged from 90% to 99.4%. For the early loading protocol, the implant and prosthesis survival rates ranged from 94.74% to 100% and 93.75% to 100%, respectively (range of follow-up, 1 to 10 years). For the conventional loading protocol, the implant and prosthesis survival rates ranged from 94.95% to 100% and 87.5% to 100%, respectively (range of follow-up, 2 to 15 years). No difference was identified between maxilla and mandible. When selecting cases carefully and using dental implants with a rough surface, immediate loading with fixed prostheses in edentulous patients results in similar implant and prosthesis survival and failure rates as early and conventional loading. For immediate loading, most of the studies recommended a minimal insertion torque of 30 Ncm. The estimated 1-year implant survival was above 99% with all three

Evolution of Muscle Activity Patterns Driving Motions of the Jaw and Hyoid during Chewing in Gnathostomes

Science.gov (United States)

Konow, Nicolai; Herrel, Anthony; Ross, Callum F.; Williams, Susan H.; German, Rebecca Z.; Sanford, Christopher P. J.; Gintof, Chris

2011-01-01

Although chewing has been suggested to be a basal gnathostome trait retained in most major vertebrate lineages, it has not been studied broadly and comparatively across vertebrates. To redress this imbalance, we recorded EMG from muscles powering anteroposterior movement of the hyoid, and dorsoventral movement of the mandibular jaw during chewing. We compared muscle activity patterns (MAP) during chewing in jawed vertebrate taxa belonging to unrelated groups of basal bony fishes and artiodactyl mammals. Our aim was to outline the evolution of coordination in MAP. Comparisons of activity in muscles of the jaw and hyoid that power chewing in closely related artiodactyls using cross-correlation analyses identified reorganizations of jaw and hyoid MAP between herbivores and omnivores. EMG data from basal bony fishes revealed a tighter coordination of jaw and hyoid MAP during chewing than seen in artiodactyls. Across this broad phylogenetic range, there have been major structural reorganizations, including a reduction of the bony hyoid suspension, which is robust in fishes, to the acquisition in a mammalian ancestor of a muscle sling suspending the hyoid. These changes appear to be reflected in a shift in chewing MAP that occurred in an unidentified anamniote stem-lineage. This shift matches observations that, when compared with fishes, the pattern of hyoid motion in tetrapods is reversed and also time-shifted relative to the pattern of jaw movement. PMID:21705368

A case of early detection of bisphosphonate-related osteonecrosis of the jaw

OpenAIRE

Mori, Miyu; Koide, Tetsuro; Matsui, Yuriyo; Matsuda, Toru

2015-01-01

Osteonecrosis of the jaws is an adverse reaction associated with the use of bisphosphonates. Although the diagnosis of bisphosphonate-related osteonecrosis of the jaw (BRONJ) is based on symptomatology, it is often detected late because the patients become symptomatic only after osteonecrosis is well established. We describe a case of early oral BRONJ detected by magnetic resonance imaging (MRI) accidentally. Head MRI revealed low signal of T1-weight images in left mandibula. Patient had been...

Radiographic features of central giant cell granuloma of the jaws in children

International Nuclear Information System (INIS)

Bodner, L.; Bar-Ziv, J.

1996-01-01

The radiographic features of ten pediatric cases of central giant cell granuloma of the jaws were studied, using plain film radiography (PFR), computed tomography (CT), and a dental CT software program (DS). The radiologic features varied from ill-defined destructive lesions to a well-defined, multilocular appearance. Teeth or root displacement was found as the most consistent feature. Root resorption was rare. The features seen on CT were clearer than those seen on PFR. DS, by its visualization of the jaw in three plans - axial, panoramic, and buccolingual - provided useful information for determining the topography of the lesion in its structure (uni- or multilocular) and proximity to adjacent anatomic structures, such as teeth, nerves, or maxillary sinus. CT and, ideally, CT with DS should be used for diagnosis and surgical management of central giant cell granuloma of the jaws in children. (orig.). With 3 figs., 1 tab

Radiographic features of central giant cell granuloma of the jaws in children

Energy Technology Data Exchange (ETDEWEB)

Bodner, L. [Department of Oral and Maxillofacial Surgery, Soroka Medical Center, P. O. Box 151, Beer-Sheva 84101 (Israel); Bar-Ziv, J. [Department of Radiology, Hebrew University and Hadassah School of Medicine, Jerusalem (Israel)

1996-02-01

The radiographic features of ten pediatric cases of central giant cell granuloma of the jaws were studied, using plain film radiography (PFR), computed tomography (CT), and a dental CT software program (DS). The radiologic features varied from ill-defined destructive lesions to a well-defined, multilocular appearance. Teeth or root displacement was found as the most consistent feature. Root resorption was rare. The features seen on CT were clearer than those seen on PFR. DS, by its visualization of the jaw in three plans - axial, panoramic, and buccolingual - provided useful information for determining the topography of the lesion in its structure (uni- or multilocular) and proximity to adjacent anatomic structures, such as teeth, nerves, or maxillary sinus. CT and, ideally, CT with DS should be used for diagnosis and surgical management of central giant cell granuloma of the jaws in children. (orig.). With 3 figs., 1 tab.

REHABILITATION OF SEVERELY ATROPHIED UPPER JAW WITH INTRAOSSAL DENTAL IMPLANTS - clinical case

Directory of Open Access Journals (Sweden)

Ivan Chenchev

2010-07-01

Full Text Available Objective: The purpose of this presentation is to show the difficulty in prosthetization of a clinical case with a pronounced atrophy of the upper jaw and the various types and nature of restrictions imposed by the requirements of the patient. Methods: The clinical analysis, surgical protocol and prosthetic solution are presented in the treatment of 72 year-old woman with a pronounced atrophy of the upper jaw. OPG, standard CT of the upper jaw was used in the planning and a special surgical template was fabricated, helping us to find intraoperatively the exact locations of implants. The preliminary analysis of the number, height and diameter of intraossal implants helped us to find the exact prosthetic solution in this clinical case. The preparation of the implant bed was done by conical osteotomy in order to expand and condense the existing bone, which allowed us to use endoossal implants with a possible maximum size in a very limited maxillary volume and the reluctance of the patient to use other methods and surgical techniques. Conical threaded and self-tapping intraossal implants were used, placed according to a classic two-stage methodology with a flap and a long-term functional loading after a period of four months.Results and Conclusion: The applied surgical and prosthetic solution allowed us to achieve a good functional and aesthetic rehabilitation in this case of severe atrophy of the upper jaw, following a number of restrictions imposed on us by the reluctance of the patient to use other surgical solutions. This shows that in the case of severe atrophy of the upper jaw, a good clinical result can be achieved. For this reason, the use of CT,a well-planned surgical template, sufficient preparation ,the maximum use of available bone volume and the choice of a good prosthetic solution is very important.

New insights into dinosaur jaw muscle anatomy.

Science.gov (United States)

Holliday, Casey M

2009-09-01

Jaw muscles are key components of the head and critical to testing hypotheses of soft-tissue homology, skull function, and evolution. Dinosaurs evolved an extraordinary diversity of cranial forms adapted to a variety of feeding behaviors. However, disparate evolutionary transformations in head shape and function among dinosaurs and their living relatives, birds and crocodylians, impair straightforward reconstructions of muscles, and other important cephalic soft tissues. This study presents the osteological correlates and inferred soft tissue anatomy of the jaw muscles and relevant neurovasculature in the temporal region of the dinosaur head. Hypotheses of jaw muscle homology were tested across a broad range archosaur and sauropsid taxa to more accurately infer muscle attachments in the adductor chambers of non-avian dinosaurs. Many dinosaurs likely possessed m. levator pterygoideus, a trait shared with lepidosaurs but not extant archosaurs. Several major clades of dinosaurs (e.g., Ornithopoda, Ceratopsidae, Sauropoda) eliminated the epipterygoid, thus impacting interpretations of m. pseudotemporalis profundus. M. pseudotemporalis superficialis most likely attached to the caudoventral surface of the laterosphenoid, a trait shared with extant archosaurs. Although mm. adductor mandibulae externus profundus and medialis likely attached to the caudal half of the dorsotemporal fossa and coronoid process, clear osteological correlates separating the individual bellies are rare. Most dinosaur clades possess osteological correlates indicative of a pterygoideus ventralis muscle that attaches to the lateral surface of the mandible, although the muscle may have extended as far as the jugal in some taxa (e.g., hadrosaurs, tyrannosaurs). The cranial and mandibular attachments of mm adductor mandibulae externus superficialis and adductor mandibulae posterior were consistent across all taxa studied. These new data greatly increase the interpretive resolution of head anatomy in

Evaluation of the dose calculation accuracy for small fields defined by jaw or MLC for AAA and Acuros XB algorithms.

Science.gov (United States)

Fogliata, Antonella; Lobefalo, Francesca; Reggiori, Giacomo; Stravato, Antonella; Tomatis, Stefano; Scorsetti, Marta; Cozzi, Luca

2016-10-01

Small field measurements are challenging, due to the physical characteristics coming from the lack of charged particle equilibrium, the partial occlusion of the finite radiation source, and to the detector response. These characteristics can be modeled in the dose calculations in the treatment planning systems. Aim of the present work is to evaluate the MU calculation accuracy for small fields, defined by jaw or MLC, for anisotropic analytical algorithm (AAA) and Acuros XB algorithms, relative to output measurements on the beam central axis. Single point output factor measurement was acquired with a PTW microDiamond detector for 6 MV, 6 and 10 MV unflattened beams generated by a Varian TrueBeam STx equipped with high definition-MLC. Fields defined by jaw or MLC apertures were set; jaw-defined: 0.6 × 0.6, 0.8 × 0.8, 1 × 1, 2 × 2, 3 × 3, 4 × 4, 5 × 5, and 10 × 10 cm 2 ; MLC-defined: 0.5 × 0.5 cm 2 to the maximum field defined by the jaw, with 0.5 cm stepping, and jaws set to: 2 × 2, 3 × 3, 4 × 4, 5 × 5, and 10 × 10 cm 2 . MU calculation was obtained with 1 mm grid in a virtual water phantom for the same fields, for AAA and Acuros algorithms implemented in the Varian eclipse treatment planning system (version 13.6). Configuration parameters as the effective spot size (ESS) and the dosimetric leaf gap (DLG) were varied to find the best parameter setting. Differences between calculated and measured doses were analyzed. Agreement better than 0.5% was found for field sizes equal to or larger than 2 × 2 cm 2 for both algorithms. A dose overestimation was present for smaller jaw-defined fields, with the best agreement, averaged over all the energies, of 1.6% and 4.6% for a 1 × 1 cm 2 field calculated by AAA and Acuros, respectively, for a configuration with ESS = 1 mm for both X and Y directions for AAA, and ESS = 1.5 and 0 mm for X and Y directions for Acuros. Conversely, a calculated dose underestimation was found for small MLC-defined fields, with the

Customized Cheek Plumper with Friction Lock Attachment for a Completely Edentulous Patient to Enhance Esthetics: A Clinical Report.

Science.gov (United States)

Bhushan, Prem; Aras, Meena A; Coutinho, Ivy; Rajagopal, Praveen; Mysore, Ashwin R; Kumar, Swati

2017-01-25

Prosthetic rehabilitation of a completely edentulous patient should never be restricted to the replacement of missing teeth. The ultimate aim of complete denture treatment should be restoration of the full range of oral functions and esthetics. Slumped cheeks are always a concern for esthetically demanding complete denture patients. This article describes a simple, scientific, cost-effective technique to improve facial esthetics in a completely edentulous patient with the help of a cheek plumper. The technique used here implements the concept of neutral zone to precisely determine the amount of space available for the cheek plumper. The simple friction lock attachments that retained the cheek plumpers on the prosthesis were also fabricated after determining the space available in the appropriate areas. Thus an effort was made to keep the cheek plumpers unobtrusive yet effective to ensure complete integration of the prosthesis into the stomatognathic system. © 2017 by the American College of Prosthodontists.

Radiolucent rim as a possible diagnostic aid for differentiating jaw lesions

Science.gov (United States)

Mortazavi, Hamed; Rahmani, Somayeh; Jafari, Soudeh; Parvaei, Parvin

2015-01-01

In this study, we formulate a new proposal that complements previous classifications in order to assist dental practitioners in performing a differential diagnosis based on patients' radiographs. We used general search engines and specialized databases such as Google Scholar, PubMed, PubMed Central, MedLine Plus, Science Direct, Scopus, and well-recognized textbooks to find relevant studies by using keywords such as "jaw disease," "jaw lesions," "radiolucent rim," "radiolucent border," and "radiolucent halo." More than 200 articles were found, of which 70 were broadly relevant to the topic. We ultimately included 50 articles that were closely related to the topic of interest. When the relevant data were compiled, the following eight lesions were identified as having a radiolucent rim: periapical cemento-osseous dysplasia, focal cemento-osseous dysplasia, florid cemento-osseous dysplasia, cemento-ossifying fibroma, osteoid osteoma, osteoblastoma, odontoma, and cementoblastoma. We propose a novel subcategory, jaw lesions with a radiolucent rim, which includes eight entities. The implementation of this new category can help improve the diagnoses that dental practitioners make based on patients' radiographs. PMID:26730374

A study of the emotional effects of tooth loss in an edentulous Gujarati population and its association with depression

Directory of Open Access Journals (Sweden)

Rupal J Shah

2015-01-01

Conclusion: About 58% of edentulous people had difficulties accepting tooth loss, which was unrelated to denture satisfaction. Respondents appeared to be restricted in social activities mainly due to functional limitations. Those with difficulties accepting tooth loss were more likely to experience depression.

Elderly with remaining teeth report less frailty and better quality of life than edentulous elderly : a cross-sectional study

NARCIS (Netherlands)

Hoeksema, A. R.; Spoorenberg, S. L. W.; Peters, L. L.; Meijer, H. J. A.; Raghoebar, G. M.; Vissink, A.; Wynia, K.; Visser, A.

ObjectiveTo assess oral status and self-reported oral health in community-living elderly and to determine differences between relevant subgroups of oral status (remaining teeth, edentulous, implant-retained overdentures) and case complexity (robust, frail, complex care needs). Subjects and methodsIn

Comparative studies of jaw morphology and ontogeny in two species of asexually reproducing Dorvilleidae (Annelida)

DEFF Research Database (Denmark)

Macnaughton, Martin Oliver; Eibye-Jacobsen, Danny; Worsaae, Katrine

2011-01-01

found in closely related species (Macnaughton et al. 2009). Details of dentition and numbers of maxillary plates as well as the ontogenetic growth patterns of the jaws were found to provide significant information of systematic value. Based on detailed studies of jaw ontogeny and morphology, Dorvillea...

Emission computer tomographic orthopan display of the jaws - method and normal values

International Nuclear Information System (INIS)

Bockisch, A.; Koenig, R.; Biersack, H.J.; Wahl, G.

1990-01-01

A tomoscintigraphic method is described to create orthopan-like projections of the jaws from SPECT bone scans using cylinder projection. On the basis of this projection a numerical analysis of the dental regions is performed in the same computer code. For each dental region the activity relative to the contralateral region and relative to the average activity of the corresponding jaw is calculated. Using this method, a set of normal activity relations has been established by investigation of 24 patients. (orig.) [de

Lost salt technique for severely resorbed alveolar ridges: An innovative approach

Directory of Open Access Journals (Sweden)

Himanshi Aggarwal

2012-01-01

Full Text Available The success of a complete denture relies on the principles of retention, stability and support. The prosthodontist skill lies in applying these principles efficiently in critical situations. Severely resorbed maxillary edentulous ridges that are narrow and constricted with increased inter ridge space provide decreased support, retention and stability. The consequent weight of the processed denture only compromises them further. This article describes a case report of an edentulous patient with resorbed ridges where a simplified technique of fabricating a hollow maxillary complete denture using lost salt technique was used for preservation of denture bearing areas. The hollowing of the denture reduces the weight of the denture, thereby enhancing stability and retention, reducing the further resorption of the jaws.

Oral health-related quality of life of edentulous patients after complete dentures relining

Directory of Open Access Journals (Sweden)

Krunić Nebojša

2015-01-01

Full Text Available Background/Aim. Tooth loss affects oral health-related life quality. More than a third of edentulous patients are not fully satisfied with their complete dentures and mainly complain of insufficient stability, retention, and pain during mastication. Solving the problem may include relining by materials that are based on silicone or acrylic. The aim of this study was to determine the level of patients’ satisfaction before and after relining upper dentures with soft and rigid liners. Methods. The patients (n = 24 were divided into two study groups. Maxillary denture relining of the first group of patients was performed with hard acrylic based resins while in the second group of patients complete denture was relined with a silicone-based soft liner. They were asked the questions from the specifically adapted the Oral Health Impact Profile Questionnaire for edentulous patients before and three months after relining dentures. Results. After relining the patients showed a higher degree of satisfaction with their dentures in all the tested domains (masticatory function, psychological discomfort, social disability and retention and hygiene. The patients with soft denture relines were more satisfied. Conclusion. Relining of maxillary complete dentures significantly positively impacts the quality of life of patients in all the tested domains (masticatory function, psychological discomfort, social disability, pain and oral hygiene. Better results were achieved using a silicone-based soft liner, which recommends it as the material of choice for relining dentures.

Detection of improvement in the masticatory function from old to new removable partial dentures using mixing ability test.

Science.gov (United States)

Asakawa, A; Fueki, K; Ohyama, T

2005-09-01

The aim of this study was to determine the sensitivity of the Mixing Ability Test to detect improvement of masticatory function in subjects on transition from old to new removable partial dentures. Thirty-two subjects (seven males, 25 females, mean age 65.0 years) with distal extension partially edentulous area in mandible and/or maxilla participated in the study. The following reasons were presented for replacing the old removable partial dentures with new ones: fracture and/or poor fitness of retainers, extraction of abutment teeth, poor fitness of denture base, severe wear of artificial teeth and request for metal base dentures. Masticatory function with old and new removable partial dentures after an adaptation period (mean 27.4 weeks) was evaluated by the Mixing Ability Test. Subjects were asked to masticate five two-coloured wax cubes with each removable partial denture. Mixing Ability Index was obtained from the colour mixture and shape of the masticated cubes. Wilcoxon signed-rank test was used to test the difference of Mixing Ability Indexes between old and new removable partial dentures. The mixing ability indexes with new removable partial dentures (mean+/- s.d.: 0.70+/- 0.68) was significantly higher (Premovable partial dentures (-0.11+/-1.13). The results suggest that the Mixing Ability Test was capable of detecting improvement in masticatory function with new removable partial dentures.

The clinical value of X-ray images of the teeth and jaws

International Nuclear Information System (INIS)

Brocklebank, Laetitia

2003-01-01

X-ray images of the teeth and jaws are required for a variety of diagnostic purposes to supplement a clinical examination, and are invaluable for providing pictorial information about the structures that cannot be examined with direct vision. They can be acquired using traditional film systems which produce analogue images, or using a variety of alternative image receptors which result in a digital image. Irrespective of the method of image acquisition they are utilised by the dental surgeon in order to benefit their patients' management. Numerous disease processes can affect the teeth and jaws, in addition to a range of developmental abnormalities. These can be classified according to a radiological sieve, which also includes artefactual and iatrogenic features. The key components of the classification are: developmental, inflammatory, traumatic, cystic, neoplastic, osteodystrophies and systemic disorders. This paper will utilise examples of radiographic images of patients to illustrate components of this classification which are unique to the teeth and jaws

Jaw dysfunction is associated with neck disability and muscle tenderness in subjects with and without chronic temporomandibular disorders.

Science.gov (United States)

Silveira, A; Gadotti, I C; Armijo-Olivo, S; Biasotto-Gonzalez, D A; Magee, D

2015-01-01

Tender points in the neck are common in patients with temporomandibular disorders (TMD). However, the correlation among neck disability, jaw dysfunction, and muscle tenderness in subjects with TMD still needs further investigation. This study investigated the correlation among neck disability, jaw dysfunction, and muscle tenderness in subjects with and without chronic TMD. Participants. Forty females between 19 and 49 years old were included in this study. There were 20 healthy controls and 20 subjects who had chronic TMD and neck disability. Subjects completed the neck disability index and the limitations of daily functions in TMD questionnaires. Tenderness of the masticatory and cervical muscles was measured using an algometer. The correlation between jaw disability and neck disability was significantly high (r = 0.915, P cervical muscles with jaw dysfunction and neck disability showed fair to moderate correlations (r = 0.32-0.65). High levels of muscle tenderness in upper trapezius and temporalis muscles correlated with high levels of jaw and neck dysfunction. Moreover, high levels of neck disability correlated with high levels of jaw disability. These findings emphasize the importance of considering the neck and its structures when evaluating and treating patients with TMD.

Clinical experiences with laser-welded titanium frameworks supported by implants in the edentulous mandible: a 5-year follow-up study.

Science.gov (United States)

Ortorp, A; Linden, B; Jemt, T

1999-01-01

The purpose of this study was to report the 5-year clinical performance of implant-supported prostheses with laser-welded titanium frameworks and to compare their performance with that of prostheses provided with conventional cast frameworks. On a routine basis, a consecutive group of 824 edentulous patients were provided with fixed prostheses supported by implants in the edentulous mandible. In addition to conventional gold-alloy castings, patients were at random provided with 2 kinds of laser-welded titanium frameworks. In all, 155 patients were included in the 2 titanium framework groups. A control group of 53 randomly selected patients with conventional gold-alloy castings was used for comparison. Clinical and radiographic 5-year data was collected for the 3 groups. All followed patients still had fixed prostheses in the mandible after 5 years. The overall cumulative success rates were 95.9% and 99.7% for titanium-framework prostheses and implants, respectively. The corresponding success rates for the control group were 100% and 99.6%, respectively. Bone loss was 0.5 mm on average during the 5-year follow-up period. The most common complications for titanium frameworks were resin or tooth fractures, gingival inflammation, and fractures of the metal frames (10%). One of the cast frameworks fractured and was resoldered. Loose and fractured implant screw components were few (laser-welded titanium frameworks seem to be a viable alternative to conventional castings in the edentulous mandible.

The earliest herbivorous marine reptile and its remarkable jaw apparatus.

Science.gov (United States)

Chun, Li; Rieppel, Olivier; Long, Cheng; Fraser, Nicholas C

2016-05-01

Newly discovered fossils of the Middle Triassic reptile Atopodentatus unicus call for a radical reassessment of its feeding behavior. The skull displays a pronounced hammerhead shape that was hitherto unknown. The long, straight anterior edges of both upper and lower jaws were lined with batteries of chisel-shaped teeth, whereas the remaining parts of the jaw rami supported densely packed needle-shaped teeth forming a mesh. The evidence indicates a novel feeding mechanism wherein the chisel-shaped teeth were used to scrape algae off the substrate, and the plant matter that was loosened was filtered from the water column through the more posteriorly positioned tooth mesh. This is the oldest record of herbivory within marine reptiles.

Toolmarks made by lathe chuck jaws.

Science.gov (United States)

Finkelstein, Nir; Aronson, Ayal; Tsach, Tsadok

2017-06-01

This paper presents a forensic method to evidentially tie a workpiece with a specific lathe. Examining using this method can prove or exclude a connection between the two. The importance of this method is mostly due to the growing trend among lawbreakers of manufacturing improvised firearm parts using machining processes. This method is based on comparing jaw impressions made by the chuck on a workpiece. Copyright © 2017 Elsevier B.V. All rights reserved.

Dosimetric effect on pediatric conformal treatment plans using dynamic jaw with Tomotherapy HDA

Energy Technology Data Exchange (ETDEWEB)

Han, Eun Young, E-mail: eyhan@uams.edu [Department of Radiation Oncology, University of Arkansas Medical Sciences, Little Rock, AR (United States); Kim, Dong-Wook [Department of Radiation Oncology, Kyung Hee University Hospital, Seoul (Korea, Republic of); Zhang, Xin; Penagaricano, Jose; Liang, Xiaoying; Hardee, Matthew; Morrill, Steve; Ratanatharathorn, Vaneerat [Department of Radiation Oncology, University of Arkansas Medical Sciences, Little Rock, AR (United States)

2015-10-01

It is important to minimize the radiation dose delivered to healthy tissues in pediatric cancer treatment because of the risk of secondary malignancies. Tomotherapy HDA provides a dynamic jaw (DJ) delivery mode that creates a sharper penumbra at the craniocaudal ends of a target in addition to a fixed jaw (FJ) delivery mode. The purpose of this study was to evaluate its dosimetric effect on the pediatric cancer cases. We included 6 pediatric cases in this study. The dose profiles and plan statistics—target dose conformity, uniformity, organ-at-risk (OAR) mean dose, beam-on time, and integral dose—were compared for each case. Consequently, the target dose coverage and uniformity were similar for different jaw settings. The OAR dose sparing depended on its relative location to the target and disease sites. For example, in the head and neck cancer cases, the brain stem dose using DJ 2.5 was reduced by more than two-fold (2.4 Gy vs. 6.3 Gy) than that obtained with FJ 2.5. The integral dose with DJ 2.5 decreased by more than 9% compared with that with FJ 2.5. Thus, using dynamic jaw in pediatric cases could be critical to reduce a probability of a secondary malignancy.

Brain activity associated with memory and cognitive function during jaw-tapping movement in healthy subjects using functional magnetic resonance imaging.

Science.gov (United States)

Cho, Seung-Yeon; Shin, Ae-Sook; Na, Byung-Jo; Jahng, Geon-Ho; Park, Seong-Uk; Jung, Woo-Sang; Moon, Sang-Kwan; Park, Jung-Mi

2013-06-01

To determine whether jaw-tapping movement, a classically described as an indication of personal well-being and mental health, stimulates the memory and the cognitive regions of the brain and is associated with improved brain performance. Twelve healthy right-handed female subjects completed the study. Each patient performed a jaw-tapping task and an n-back task during functional magnetic resonance imaging (fMRI). The subjects were trained to carry out the jaw-tapping movement at home twice a day for 4 weeks. The fMRI was repeated when they returned. During the first and second jaw-tapping session, both sides of precentral gyrus and the right middle frontal gyrus (BA 6) were activated. And during the second session of the jaw-tapping task, parts of frontal lobe and temporal lobe related to memory function were more activated. In addition, the total percent task accuracy in n-back task significantly increased after 4 weeks of jawtapping movement. After jaw-tapping training for 4 weeks, brain areas related to memory showed significantly increased blood oxygen level dependent signals. Jaw-tapping movement might be a useful exercise for stimulating the memory and cognitive regions of the brain.

surgical management of aggressive synchronous jaw central giant ...

African Journals Online (AJOL)

2012-08-08

Aug 8, 2012 ... Central giant cell granuloma ( CGCG) appears to be a lesion that is unique to the jaws. It is difficult to ... have been noted, particularly in the long bones. Though rare ... examination and biochemical and radiographic investigations are ... A photomicrograph depicting histopathologic features consistent with ...

Sella size and jaw bases - Is there a correlation???

Directory of Open Access Journals (Sweden)

Neha

2016-01-01

Full Text Available Introduction: Sella turcica is an important cephalometric structure and attempts have been made in the past to correlate its dimensions to the malocclusion. However, no study has so far compared the size of sella to the jaw bases that determine the type of malocclusion. The present study was undertaken to find out any such correlation if it exists. Materials and Methods: Lateral cephalograms of 110 adults consisting of 40 Class I, 40 Class II, and 30 Class III patients were assessed for the measurement of sella length, width, height, and area. The maxillary length, mandibular ramus height, and body length were also measured. The sella dimensions were compared among three malocclusion types by one-way ANOVA. Pearson correlation was calculated between the jaw size and sella dimensions. Furthermore, the ratio of jaw base lengths and sella area were calculated. Results and Conclusion: Mean sella length, width and area were found to be greatest in Class III, followed by Class I and least in Class II though the results were not statistically significant. 3 out of 4 measured dimensions of sella, correlated significantly with mandibular ramus and body length each. However, only one dimension of sella showed significant correlation with maxilla. The mandibular ramus and body length show a nearly constant ratio to sella area (0.83–0.85, 0.64–0.65, respectively in all the three malocclusions. Thus, mandible has a definite and better correlation to the size of sella turcica.

Ameloblastomatous Change in Radicular Cyst of The Jaw in a Nigerian Population.

Science.gov (United States)

Omoregie, F O; Sede, M A; Ojo, A M

2015-06-01

To determine the incidence, age, gender, jaw-sites and subtypes of radicular cyst, and to determine the incidence of ameloblastomatous change in radicular cyst in a Nigerian population. A 10-year retrospective analysis of all diagnosed orofacial lesions in the Department of Oral Pathology and Medicine, University of Benin Teaching Hospital, Benin City, Nigeria. From the 785 diagnosed orofacial lesions within the study period; there were 54 (6.9%) cases of radicular cysts of the jaws. The peak age group was the 3(rd) decade (n=23, 42.6%) with a mean age of 31 ± 1.7 years. There were 29 (53.7%) males and 25 (46.3%) females, giving a ratio of 1.2:1. The mandible was the commonest jaw-site (n=32, 59.3%). There were 12 (22.2%) cases of periapical cyst which were significantly associated with anterior maxillary site (n=8, 14.8%) [p=0.001]. Seven (13.0%) cases of cystic ameloblastoma were diagnosed among the radicular cysts, with a predilection of the lesions for 3(rd) and 4(th) decades of life (n=6, 11.1%), and posterior mandible (n=5, 9.3%). This study showed a low incidence of radicular cyst of the jaw among orofacial lesions and a relatively higher incidence of ameloblastomatous change in radicular cyst compared to previous reports. Immuno-histochemical examination is recommended to differentiate radicular cyst with ameloblastomatous-like change from cystic ameloblastoma arising from radicular cyst.

Dental diseases and radionuclide imaging of the jaws.

Science.gov (United States)

Arias, Jose A; Pardo, Carlos; Olmos, Antonio; Cuadrado, Maria L; Ruibal, Alvaro

2004-03-01

The aim of this study was to compare the results of radionuclide bone scans of the jaws with data obtained at the nuclear medicine department from a brief and feasible dental history, taking special account of cases with a positive scan and no recent dental events. Ninety-eight patients undergoing radionuclide bone scan as part of their diagnosis in non-dental, oncological and non-oncological diseases were imaged with 99mTc-labelled oxidronate. Superior and inferior halves of the mandible and maxilla (392 quadrants) were regarded as normal or having an abnormally high uptake. A recent (1 year) dental history was also obtained through a brief questionnaire and data were referred to each quadrant of the jaws. The association between the bone scan and dental disease was assessed by means of the chi-squared test. The overall results of scintigraphy and history coincided in 66 patients (46 with abnormal and 20 with normal findings; P = 0.002). Twenty-five patients had a positive scintigram without any known dental disorder. Results of scintigraphy and history coincided in 254 quadrants (78 with abnormal and 176 with normal findings; P < 0.001). Eighty-three quadrants had hot spots in the scintigram without any known dental lesion. It can be concluded that abnormal jaw scintigrams are frequent in patients without known dental disease, and this may indicate silent osteoblastic activity. These observations should be reported to the dentist for several reasons. First, they may reveal asymptomatic dental lesions. Second, the use of oral prostheses and implants is increasing and they require the support of healthy alveolar bone.

Some additional Notes on external Features and on the jaw muscles of Orthragoriscus mola (L.)

NARCIS (Netherlands)

Roon, van J.M.

1942-01-01

In 1939 J. M. van Roon and J. J. ter Pelkwijk published some data on two specimens of Orthragoriscus mola (L.) stranded on the Dutch coast. Measurements of bones and muscles of the jaw were given on account of the functional treatise concerning the mechanism of the jaw of Orthragoriscus given by Van

Oroantral fistula from bisphosphonate induced osteonecrosis of the jaw

Directory of Open Access Journals (Sweden)

Henry Sharp

2010-07-01

Full Text Available Bisphosphonates like alendronic acid, disodium etidronate, and risedronate are effective for preventing postmenopausal and corticosteroid induced osteoporosis. They are also useful in the treatment of Paget’s disease, hypercalcaemia of malignancy and in bony metastases. However osteonecrosis of the jaw has been reported following intravenous bisphosphonate use and rarely in those taking them orally.Increasingly, oroantral fistulae have been shown to occur as sequelae of bisphosphonate-induced osteonecrosis of the jaw and this case report highlights a patient that presented to our ENT department and required sinus surgery in collaboration with maxillofacial surgeons.This case report aims to raise awareness among ENT surgeons to these patients on bisphosphonates that could present to them with sinus disease from oroantral fistulae. There is an on-going audit in the maxillofacial community on this emerging trend.

Outcomes Assessment of Treating Completely Edentulous Patients with a Fixed Implant-Supported Profile Prosthesis Utilizing a Graftless Approach. Part 1: Clinically Related Outcomes.

Science.gov (United States)

Alzoubi, Fawaz; Bedrossian, Edmond; Wong, Allen; Farrell, Douglas; Park, Chan; Indresano, Thomas

To assess outcomes of treating completely edentulous patients with a fixed implant-supported profile prosthesis utilizing a graftless approach for the maxilla and for the mandible, with emphasis on clinically related outcomes, specifically implant and prosthesis survival. This was a retrospective study with the following inclusion criteria: completely edentulous patients rehabilitated with a fixed implant-supported profile denture utilizing a graftless approach. Patients fulfilling the inclusion criteria were asked to participate in the study during their follow-up visits, and hence a consecutive sampling strategy was used. Data regarding implant and prosthesis cumulative survival rates (CSRs) were gathered and calculated. Thirty-four patients were identified with a total of 220 implants placed. An overall CSR of 98.2% was recorded with an observation of up to 10 years. For tilted, axial, and zygomatic implants, CSRs of 96.9%, 98.0%, and 100%, respectively, were observed for up to 10 years. For provisional prostheses, CSRs of 92.3% at 1 year, and 84.6% at 2 years were observed. For final prostheses, a CSR of 93.8% was observed at 10 years. The results suggest that treating completely edentulous patients with a fixed profile prosthesis utilizing a graftless approach in the maxilla and the mandible can be a reliable treatment option.

Postural stability and the influence of concurrent muscle activation--Beneficial effects of jaw and fist clenching.

Science.gov (United States)

Ringhof, Steffen; Leibold, Timo; Hellmann, Daniel; Stein, Thorsten

2015-10-01

Recent studies reported on the potential benefits of submaximum clenching of the jaw on human postural control in upright unperturbed stance. However, it remained unclear whether these effects might also be observed among active controls. The purpose of the present study, therefore, was to comparatively examine the influence of concurrent muscle activation in terms of submaximum clenching of the jaw and submaximum clenching of the fists on postural stability. Posturographic analyses were conducted with 17 healthy young adults on firm and foam surfaces while either clenching the jaw (JAW) or clenching the fists (FIST), whereas habitual standing served as the control condition (CON). Both submaximum tasks were performed at 25% maximum voluntary contraction, assessed, and visualized in real time by means of electromyography. Statistical analyses revealed that center of pressure (COP) displacements were significantly reduced during JAW and FIST, but with no differences between both concurrent clenching activities. Further, a significant increase in COP displacements was observed for the foam as compared to the firm condition. The results showed that concurrent muscle activation significantly improved postural stability compared with habitual standing, and thus emphasize the beneficial effects of jaw and fist clenching for static postural control. It is suggested that concurrent activities contribute to the facilitation of human motor excitability, finally increasing the neural drive to the distal muscles. Future studies should evaluate whether elderly or patients with compromised postural control might benefit from these physiological responses, e.g., in the form of a reduced risk of falling. Copyright © 2015 Elsevier B.V. All rights reserved.

The evolution of jaw protrusion mechanics is tightly coupled to bentho-pelagic divergence in damselfishes (Pomacentridae).

Science.gov (United States)

Cooper, W James; Carter, Casey B; Conith, Andrew J; Rice, Aaron N; Westneat, Mark W

2017-02-15

Most species-rich lineages of aquatic organisms have undergone divergence between forms that feed from the substrate (benthic feeding) and forms that feed from the water column (pelagic feeding). Changes in trophic niche are frequently accompanied by changes in skull mechanics, and multiple fish lineages have evolved highly specialized biomechanical configurations that allow them to protrude their upper jaws toward the prey during feeding. Damselfishes (family Pomacentridae) are an example of a species-rich lineage with multiple trophic morphologies and feeding ecologies. We sought to determine whether bentho-pelagic divergence in the damselfishes is tightly coupled to changes in jaw protrusion ability. Using high-speed video recordings and kinematic analysis, we examined feeding performance in 10 species that include three examples of convergence on herbivory, three examples of convergence on omnivory and two examples of convergence on planktivory. We also utilized morphometrics to characterize the feeding morphology of an additional 40 species that represent all 29 damselfish genera. Comparative phylogenetic analyses were then used to examine the evolution of trophic morphology and biomechanical performance. We find that pelagic-feeding damselfishes (planktivores) are strongly differentiated from extensively benthic-feeding species (omnivores and herbivores) by their jaw protrusion ability, upper jaw morphology and the functional integration of upper jaw protrusion with lower jaw abduction. Most aspects of cranial form and function that separate these two ecological groups have evolved in correlation with each other and the evolution of the functional morphology of feeding in damselfishes has involved repeated convergence in form, function and ecology. © 2017. Published by The Company of Biologists Ltd.

APPLICATION OF 3D MODELING IN 3D PRINTING FOR THE LOWER JAW RECONSTRUCTION

Directory of Open Access Journals (Sweden)

Yu. Yu. Dikov

2015-01-01

Full Text Available Aim of study: improvement of functional and aesthetic results of microsurgery reconstructions of the lower jaw due to the use of the methodology of 3D modeling and 3D printing. Application of this methodology has been demonstrated on the example of treatment of 4 patients with locally distributed tumors of the mouth cavity, who underwent excision of the tumor with simultaneous reconstruction of the lower jaw with revascularized fibular graft.Before, one patient has already undergo segmental resection of the lower jaw with the defect replacement with the avascular ileac graft and a reconstruction plate. Then, a relapse of the disease and lysis of the graft has developed with him. Modeling of the graft according to the shape of the lower jaw was performed by making osteotomies of the bone part of the graft using three-dimensional virtual models created by computed tomography data. Then these 3D models were printed with a 3D printer of plastic with the scale of 1:1 with the fused deposition modeling (FDM technology and were used during the surgery in the course of modeling of the graft. Sterilizing of the plastic model was performed in the formalin chamber.This methodology allowed more specific reconstruction of the resected fragment of the lower jaw and get better functional and aesthetic results and prepare patients to further dental rehabilitation. Advantages of this methodology are the possibility of simultaneous performance of stages of reconstruction and resection and shortening of the time of surgery.

Convergent evolution of jaws between spinosaurid dinosaurs and pike conger eels

Directory of Open Access Journals (Sweden)

Romain Vullo

2016-12-01

Full Text Available Spinosaurs represent a group of peculiar theropod dinosaurs that have often been described as “crocodile-mimic”, predominantly fish-eating predators, and recently claimed to have been semi-aquatic animals. Here we report a suite of craniodental characters unexpectedly shared by spinosaurs and pike conger eels. Pike conger eels are predatory, mainly piscivorous bottom-dwelling anguilliform fishes that inhabit marine and brackish environments. These two groups of dinosaurs and fishes show a mediolaterally compressed, elongated rostrum, a terminal “rosette” bearing enlarged teeth in both upper and lower jaws, and a notch posterior to the premaxillary “rosette” characterized by the presence of reduced teeth. The morphological convergence observed in the jaws of these two distantly related groups of vertebrates may result from similar feeding behaviours. This typical jaw morphology likely represents an effective biomechanical adaptation for biting and grabbing elusive prey items in low-light aquatic environments. Associated with this specialized snout morphology, numerous integumentary mechanoreceptors involved in prey detection are present in both spinosaurs and pike congers. Our new observations provide an additional convincing argument regarding the decades-long and widely debated lifestyle of spinosaurs.

Radiolucent rim as a possible diagnostic aid for differentiating jaw lesions

Energy Technology Data Exchange (ETDEWEB)

Mortazavi, Hamed; Baharvand, Maryam; Rarahmani, Somayeh; Jafati, Soudeh; Parvaei, Parvin [Oral Medicine, School of Dentistry, Shahid Beheshti University of Medical Sciences, Tehran (Iran, Islamic Republic of)

2015-12-15

In this study, we formulate a new proposal that complements previous classifications in order to assist dental practitioners in performing a differential diagnosis based on patients' radiographs. We used general search engines and specialized databases such as Google Scholar, PubMed, PubMed Central, MedLine Plus, Science Direct, Scopus, and well-recognized textbooks to find relevant studies by using keywords such as 'jaw disease,' 'jaw lesions,' 'radiolucent rim,' 'radiolucent border,' and 'radiolucent halo.' More than 200 articles were found, of which 70 were broadly relevant to the topic. We ultimately included 50 articles that were closely related to the topic of interest. When the relevant data were compiled, the following eight lesions were identified as having a radiolucent rim: periapical cemento-osseous dysplasia, focal cemento-osseous dysplasia, florid cemento-osseous dysplasia, cemento-ossifying fibroma, osteoid osteoma, osteoblastoma, odontoma, and cementoblastoma. We propose a novel subcategory, jaw lesions with a radiolucent rim, which includes eight entities. The implementation of this new category can help improve the diagnoses that dental practitioners make based on patients' radiographs.

Radiolucent rim as a possible diagnostic aid for differentiating jaw lesions

International Nuclear Information System (INIS)

Mortazavi, Hamed; Baharvand, Maryam; Rarahmani, Somayeh; Jafati, Soudeh; Parvaei, Parvin

2015-01-01

In this study, we formulate a new proposal that complements previous classifications in order to assist dental practitioners in performing a differential diagnosis based on patients' radiographs. We used general search engines and specialized databases such as Google Scholar, PubMed, PubMed Central, MedLine Plus, Science Direct, Scopus, and well-recognized textbooks to find relevant studies by using keywords such as 'jaw disease,' 'jaw lesions,' 'radiolucent rim,' 'radiolucent border,' and 'radiolucent halo.' More than 200 articles were found, of which 70 were broadly relevant to the topic. We ultimately included 50 articles that were closely related to the topic of interest. When the relevant data were compiled, the following eight lesions were identified as having a radiolucent rim: periapical cemento-osseous dysplasia, focal cemento-osseous dysplasia, florid cemento-osseous dysplasia, cemento-ossifying fibroma, osteoid osteoma, osteoblastoma, odontoma, and cementoblastoma. We propose a novel subcategory, jaw lesions with a radiolucent rim, which includes eight entities. The implementation of this new category can help improve the diagnoses that dental practitioners make based on patients' radiographs

Cell based bone tissue engineering in jaw defects

NARCIS (Netherlands)

Meijer, Gert J.; de Bruijn, Joost Dick; Koole, Ron; van Blitterswijk, Clemens

2008-01-01

In 6 patients the potency of bone tissue engineering to reconstruct jaw defects was tested. After a bone marrow aspirate was taken, stem cells were cultured, expanded and grown for 7 days on a bone substitute in an osteogenic culture medium to allow formation of a layer of extracellular bone matrix.

Assessment of the increased calcification of the jaw bone with CT-Scan after dental implant placement.

Science.gov (United States)

Yunus, Barunawaty

2011-06-01

This study was performed to evaluate the changes of jaw bone density around the dental implant after placement using computed tomography scan (CT-Scan). This retrospective study consisted of 30 patients who had lost 1 posterior tooth in maxilla or mandible and installed dental implant. The patients took CT-Scan before and after implant placement. Hounsfield Unit (HU) was measured around the implants and evaluated the difference of HU before and after implant installation. The mean HU of jaw bone was 542.436 HU and 764.9 HU before and after implant placement, respectively (p<0.05). The means HUs for male were 632.3 HU and 932.2 HU and those for female 478.2 HU and 645.5 HU before and after implant placement, respectively (p<0.05). Also, the jaw bone with lower density needed longer period for implant procedure and the increased change of HU of jaw bone was less in the cases which needed longer period for osseointegration. CT-Scan could be used to assess the change of bone density around dental implants. Bone density around dental implant was increased after placement. The increased rate of bone density could be determined by the quality of jaw bone before implant placement.

Assessment of the increased calcification of the jaw bone with CT-Scan after dental implant placement

Energy Technology Data Exchange (ETDEWEB)

Yunus, Barunawaty [Faculty of Dentistry, Hasanuddin University, Makassar (Malaysia)

2011-06-15

This study was performed to evaluate the changes of jaw bone density around the dental implant after placement using computed tomography scan (CT-Scan). This retrospective study consisted of 30 patients who had lost 1 posterior tooth in maxilla or mandible and installed dental implant. The patients took CT-Scan before and after implant placement. Hounsfield Unit (HU) was measured around the implants and evaluated the difference of HU before and after implant installation. The mean HU of jaw bone was 542.436 HU and 764.9 HU before and after implant placement, respectively (p<0.05). The means HUs for male were 632.3 HU and 932.2 HU and those for female 478.2 HU and 645.5 HU before and after implant placement, respectively (p<0.05). Also, the jaw bone with lower density needed longer period for implant procedure and the increased change of HU of jaw bone was less in the cases which needed longer period for osseointegration. CT-Scan could be used to assess the change of bone density around dental implants. Bone density around dental implant was increased after placement. The increased rate of bone density could be determined by the quality of jaw bone before implant placement.

Assessment of the increased calcification of the jaw bone with CT-Scan after dental implant placement

International Nuclear Information System (INIS)

Yunus, Barunawaty

2011-01-01

This study was performed to evaluate the changes of jaw bone density around the dental implant after placement using computed tomography scan (CT-Scan). This retrospective study consisted of 30 patients who had lost 1 posterior tooth in maxilla or mandible and installed dental implant. The patients took CT-Scan before and after implant placement. Hounsfield Unit (HU) was measured around the implants and evaluated the difference of HU before and after implant installation. The mean HU of jaw bone was 542.436 HU and 764.9 HU before and after implant placement, respectively (p<0.05). The means HUs for male were 632.3 HU and 932.2 HU and those for female 478.2 HU and 645.5 HU before and after implant placement, respectively (p<0.05). Also, the jaw bone with lower density needed longer period for implant procedure and the increased change of HU of jaw bone was less in the cases which needed longer period for osseointegration. CT-Scan could be used to assess the change of bone density around dental implants. Bone density around dental implant was increased after placement. The increased rate of bone density could be determined by the quality of jaw bone before implant placement.

Hyperparathyroidism-jaw Tumor Syndrome: An Overlooked Cause of Severe Hypercalcemia.

Science.gov (United States)

Mathews, Joseph Wolfgang; Winchester, Rhonda; Alsaygh, Nebras; Bartlett, Anne M; Luttrell, Louis

2016-09-01

Ossifying fibromas of the maxillofacial bones are an uncommon form of benign neoplasm usually treated by surgical excision. Up to 30% of patients with hyperparathyroidism-jaw tumor syndrome, a rare form of multiple endocrine neoplasia resulting from autosomal dominant inactivating mutation of the Hrpt2 tumor suppressor gene, initially present with ossifying fibromas. Coincident hypercalcemia because of the presence of parathyroid adenoma is common in these patients, of whom 15% may have or may develop parathyroid carcinoma. The authors present a case of severe postsurgical hypercalcemia after removal of a large maxillary ossifying fibroma in a patient with previously unrecognized hyperparathyroidism-jaw tumor AU3 syndrome. Copyright © 2016 Southern Society for Clinical Investigation. Published by Elsevier Inc. All rights reserved.

Modulation of jaw muscle spindle afferent activity following intramuscular injections with hypertonic saline.

Science.gov (United States)

Ro, J Y; Capra, N F

2001-05-01

Transient noxious chemical stimulation of small diameter muscle afferents modulates jaw movement-related responses of caudal brainstem neurons. While it is likely that the effect is mediated from the spindle afferents in the mesencephalic nucleus (Vmes) via the caudally projecting Probst's tract, the mechanisms of pain induced modulations of jaw muscle spindle afferents is not known. In the present study, we tested the hypothesis that jaw muscle nociceptors gain access to muscle spindle afferents in the same muscle via central mechanisms and alter their sensitivity. Thirty-five neurons recorded from the Vmes were characterized as muscle spindle afferents based on their responses to passive jaw movements, muscle palpation, and electrical stimulation of the masseter nerve. Each cell was tested by injecting a small volume (250 microl) of either 5% hypertonic and/or isotonic saline into the receptor-bearing muscle. Twenty-nine units were tested with 5% hypertonic saline, of which 79% (23/29) showed significant modulation of mean firing rates (MFRs) during one or more phases of ramp-and-hold movements. Among the muscle spindle primary-like units (n = 12), MFRs of 4 units were facilitated, five reduced, two showed mixed responses and one unchanged. In secondary-like units (n = 17), MFRs of 9 were facilitated, three reduced and five unchanged. Thirteen units were tested with isotonic saline, of which 77% showed no significant changes of MFRs. Further analysis revealed that the hypertonic saline not only affected the overall output of muscle spindle afferents, but also increased the variability of firing and altered the relationship between afferent signal and muscle length. These results demonstrated that activation of muscle nociceptors significantly affects proprioceptive properties of jaw muscle spindles via central neural mechanisms. The changes can have deleterious effects on oral motor function as well as kinesthetic sensibility.

Jaw cyst-Basal cell nevus-Bifid rib syndrome: A case report

Directory of Open Access Journals (Sweden)

Rai S

2007-09-01

Full Text Available Jaw cyst-Basal cell nevus-Bifid rib syndrome or Gorlin-Goltz syndrome involves multiple organ system. The most common findings include multiple odontogenic keratocysts in the jaws and basal cell nevus on the skin that have an early age onset. These multiple odontogenic keratocysts warrant aggressive treatment at the earliest because of the damage and possible complications associated with them. Recurrence in these lesions is the most characteristic feature that has to be taken in consideration while explaining the prognosis to the patient. A case report of a child affected with Gorlin-Goltz syndrome diagnosed, treated and followed at this hospital is presented here.

Prevention of functional disorders of temple-lower-jaw joints in the orthopedic treatment of patients with terminal defects of teeth row

Directory of Open Access Journals (Sweden)

Tokmakova E.V.

2011-03-01

Full Text Available The study of temple-lower-jaw joints was provided in 40 patients with defects of teeth row, complicated with distal displacement of lower jaw. It was functional disorders of temple-lower-jaw joint and identified the possibility of their prevention

Fit accuracy of metal partial removable dental prosthesis frameworks fabricated by traditional or light curing modeling material technique: An in vitro study

Science.gov (United States)

Anan, Mohammad Tarek M.; Al-Saadi, Mohannad H.

2015-01-01

Objective The aim of this study was to compare the fit accuracies of metal partial removable dental prosthesis (PRDP) frameworks fabricated by the traditional technique (TT) or the light-curing modeling material technique (LCMT). Materials and methods A metal model of a Kennedy class III modification 1 mandibular dental arch with two edentulous spaces of different spans, short and long, was used for the study. Thirty identical working casts were used to produce 15 PRDP frameworks each by TT and by LCMT. Every framework was transferred to a metal master cast to measure the gap between the metal base of the framework and the crest of the alveolar ridge of the cast. Gaps were measured at three points on each side by a USB digital intraoral camera at ×16.5 magnification. Images were transferred to a graphics editing program. A single examiner performed all measurements. The two-tailed t-test was performed at the 5% significance level. Results The mean gap value was significantly smaller in the LCMT group compared to the TT group. The mean value of the short edentulous span was significantly smaller than that of the long edentulous span in the LCMT group, whereas the opposite result was obtained in the TT group. Conclusion Within the limitations of this study, it can be concluded that the fit of the LCMT-fabricated frameworks was better than the fit of the TT-fabricated frameworks. The framework fit can differ according to the span of the edentate ridge and the fabrication technique for the metal framework. PMID:26236129

Dosimetric effect on pediatric conformal treatment plans using dynamic jaw with Tomotherapy HDA.

Science.gov (United States)

Han, Eun Young; Kim, Dong-Wook; Zhang, Xin; Penagaricano, Jose; Liang, Xiaoying; Hardee, Matthew; Morrill, Steve; Ratanatharathorn, Vaneerat

2015-01-01

It is important to minimize the radiation dose delivered to healthy tissues in pediatric cancer treatment because of the risk of secondary malignancies. Tomotherapy HDA provides a dynamic jaw (DJ) delivery mode that creates a sharper penumbra at the craniocaudal ends of a target in addition to a fixed jaw (FJ) delivery mode. The purpose of this study was to evaluate its dosimetric effect on the pediatric cancer cases. We included 6 pediatric cases in this study. The dose profiles and plan statistics—target dose conformity, uniformity, organ-at-risk (OAR) mean dose, beam-on time, and integral dose—were compared for each case. Consequently, the target dose coverage and uniformity were similar for different jaw settings. The OAR dose sparing depended on its relative location to the target and disease sites. For example, in the head and neck cancer cases, the brain stem dose using DJ 2.5 was reduced by more than two-fold (2.4 Gy vs. 6.3 Gy) than that obtained with FJ 2.5. The integral dose with DJ 2.5 decreased by more than 9% compared with that with FJ 2.5. Thus, using dynamic jaw in pediatric cases could be critical to reduce a probability of a secondary malignancy. Copyright © 2015 American Association of Medical Dosimetrists. Published by Elsevier Inc. All rights reserved.

Adaptive phenotypic plasticity in the Midas cichlid fish pharyngeal jaw and its relevance in adaptive radiation

Directory of Open Access Journals (Sweden)

Salzburger Walter

2011-04-01

Full Text Available Abstract Background Phenotypic evolution and its role in the diversification of organisms is a central topic in evolutionary biology. A neglected factor during the modern evolutionary synthesis, adaptive phenotypic plasticity, more recently attracted the attention of many evolutionary biologists and is now recognized as an important ingredient in both population persistence and diversification. The traits and directions in which an ancestral source population displays phenotypic plasticity might partly determine the trajectories in morphospace, which are accessible for an adaptive radiation, starting from the colonization of a novel environment. In the case of repeated colonizations of similar environments from the same source population this "flexible stem" hypothesis predicts similar phenotypes to arise in repeated subsequent radiations. The Midas Cichlid (Amphilophus spp. in Nicaragua has radiated in parallel in several crater-lakes seeded by populations originating from the Nicaraguan Great Lakes. Here, we tested phenotypic plasticity in the pharyngeal jaw of Midas Cichlids. The pharyngeal jaw apparatus of cichlids, a second set of jaws functionally decoupled from the oral ones, is known to mediate ecological specialization and often differs strongly between sister-species. Results We performed a common garden experiment raising three groups of Midas cichlids on food differing in hardness and calcium content. Analyzing the lower pharyngeal jaw-bones we find significant differences between diet groups qualitatively resembling the differences found between specialized species. Observed differences in pharyngeal jaw expression between groups were attributable to the diet's mechanical resistance, whereas surplus calcium in the diet was not found to be of importance. Conclusions The pharyngeal jaw apparatus of Midas Cichlids can be expressed plastically if stimulated mechanically during feeding. Since this trait is commonly differentiated - among

Adaptive phenotypic plasticity in the Midas cichlid fish pharyngeal jaw and its relevance in adaptive radiation.

Science.gov (United States)

Muschick, Moritz; Barluenga, Marta; Salzburger, Walter; Meyer, Axel

2011-04-30

Phenotypic evolution and its role in the diversification of organisms is a central topic in evolutionary biology. A neglected factor during the modern evolutionary synthesis, adaptive phenotypic plasticity, more recently attracted the attention of many evolutionary biologists and is now recognized as an important ingredient in both population persistence and diversification. The traits and directions in which an ancestral source population displays phenotypic plasticity might partly determine the trajectories in morphospace, which are accessible for an adaptive radiation, starting from the colonization of a novel environment. In the case of repeated colonizations of similar environments from the same source population this "flexible stem" hypothesis predicts similar phenotypes to arise in repeated subsequent radiations. The Midas Cichlid (Amphilophus spp.) in Nicaragua has radiated in parallel in several crater-lakes seeded by populations originating from the Nicaraguan Great Lakes. Here, we tested phenotypic plasticity in the pharyngeal jaw of Midas Cichlids. The pharyngeal jaw apparatus of cichlids, a second set of jaws functionally decoupled from the oral ones, is known to mediate ecological specialization and often differs strongly between sister-species. We performed a common garden experiment raising three groups of Midas cichlids on food differing in hardness and calcium content. Analyzing the lower pharyngeal jaw-bones we find significant differences between diet groups qualitatively resembling the differences found between specialized species. Observed differences in pharyngeal jaw expression between groups were attributable to the diet's mechanical resistance, whereas surplus calcium in the diet was not found to be of importance. The pharyngeal jaw apparatus of Midas Cichlids can be expressed plastically if stimulated mechanically during feeding. Since this trait is commonly differentiated--among other traits--between Midas Cichlid species, its plasticity

Rehabilitation of an edentulous cleft lip and palate patient with a soft palate defect using a bar-retained, implant-supported speech-aid prosthesis: a clinical report.

Science.gov (United States)

Hakan Tuna, S; Pekkan, Gurel; Buyukgural, Bulent

2009-01-01

Prosthetic rehabilitation of an edentulous cleft lip and palate patient with a combined hard and soft palate defect is a great challenge, due to the lack of retention of the obturator prosthesis as a result of its weight and the inability to obtain a border seal. Dental implants improve the retention, stability, and occlusal function of prostheses when used in carefully selected cleft lip and palate cases. This clinical report presents an edentulous unilateral cleft lip and palate patient who has hard and soft palate defects and an atrophied maxilla, treated with an implant-supported speech-aid prosthesis.

Processing system of jaws tomograms for pathology identification and surgical guide modeling

Energy Technology Data Exchange (ETDEWEB)

Putrik, M. B., E-mail: pmb-88@mail.ru; Ivanov, V. Yu. [Ural Federal University named after the first President of Russia B.N. Yeltsin, Yekaterinburg (Russian Federation); Lavrentyeva, Yu. E. [Private dental clinic «Uraldent», Yekaterinburg (Russian Federation)

2015-11-17

The aim of the study is to create an image processing system, which allows dentists to find pathological resorption and to build surgical guide surface automatically. X-rays images of jaws from cone beam tomography or spiral computed tomography are the initial data for processing. One patient’s examination always includes up to 600 images (or tomograms), that’s why the development of processing system for fast automation search of pathologies is necessary. X-rays images can be useful not for only illness diagnostic but for treatment planning too. We have studied the case of dental implantation – for successful surgical manipulations surgical guides are used. We have created a processing system that automatically builds jaw and teeth boundaries on the x-ray image. After this step, obtained teeth boundaries used for surgical guide surface modeling and jaw boundaries limit the area for further pathologies search. Criterion for the presence of pathological resorption zones inside the limited area is based on statistical investigation. After described actions, it is possible to manufacture surgical guide using 3D printer and apply it in surgical operation.

Processing system of jaws tomograms for pathology identification and surgical guide modeling

International Nuclear Information System (INIS)

Putrik, M. B.; Ivanov, V. Yu.; Lavrentyeva, Yu. E.

2015-01-01

The aim of the study is to create an image processing system, which allows dentists to find pathological resorption and to build surgical guide surface automatically. X-rays images of jaws from cone beam tomography or spiral computed tomography are the initial data for processing. One patient’s examination always includes up to 600 images (or tomograms), that’s why the development of processing system for fast automation search of pathologies is necessary. X-rays images can be useful not for only illness diagnostic but for treatment planning too. We have studied the case of dental implantation – for successful surgical manipulations surgical guides are used. We have created a processing system that automatically builds jaw and teeth boundaries on the x-ray image. After this step, obtained teeth boundaries used for surgical guide surface modeling and jaw boundaries limit the area for further pathologies search. Criterion for the presence of pathological resorption zones inside the limited area is based on statistical investigation. After described actions, it is possible to manufacture surgical guide using 3D printer and apply it in surgical operation

New 3D technologies applied to assess the long-term clinical effects of misfit of the full jaw fixed prosthesis on dental implants.

Science.gov (United States)

Jokstad, Asbjørn; Shokati, Babak

2015-10-01

To assess implant:suprastructure misfit in patients with an edentulous jaw restored by an implant-retained fixed dental prosthesis (FDP) and its association with biologic and mechanical adverse events over an extensive period. Thirty patients with an edentulous mandible treated with implant-supported prosthetics before 2000 were examined clinically in 2012. Each patient had received 4 to 6 implants to retain a FDP made from acrylic and three different metal alloys, that is, Ag-Pd, Pd-Ag, and Au type IV. The implant intra-oral locations were recorded digitally by use of an intra-oral scanner, and the intaglio surface of the detached FDP was recorded using a desktop scanner. The fit was estimated by digital matching of the STL files using industrial metrological software. The average misfit was correlated with the average marginal bone loss and the prevalence of screw loosening or fractures, using the patient as the statistical unit. Over an average of 19 years (range 12 to 32), 5 implants had been lost in 4 participants (96.7% implant survival) and 8 eight prostheses (26.7%) had been remade. Anaverage misfit was 150 μm (SD 35, range 95-232, CI 138-163). An average marginal bone loss of 2.2 mm (SD = 0.7) had occurred (range 0.6 to 5.8 mm) for individual implants. The correlation between framework misfit and marginal bone loss was weak (R² = 0.04) (P = 0.29). The prostheses with a history of screw-related adverse events showed average misfit of 169 μm (SD = 32) vs. those with no history of screw-related adverse events, that is, 134 μm (SD = 30) (P = 0.005, Student's t-test). Fourteen of the 30 participants had experienced at least one incidence of screw loosening or fracture of prosthetic or abutment screw(s) over the period of follow-up. The occurrence among the frameworks fabricated with different metal alloys did not differ (P > 0.05, Fisher's exact test). Combining STL files with best-fit algorithms to appraise misfit is feasible using

Imaging of jaw with dental CT software program: Normal Anatomy

International Nuclear Information System (INIS)

Kim, Myong Gon; Seo, Kwang Hee; Jung, Hak Young; Sung, Nak Kwan; Chung, Duk Soo; Kim, Ok Dong; Lee, Young Hwan

1994-01-01

Dental CT software program can provide reformatted cross-sectional and panoramic images that cannot be obtained with conventional axial and direct coronal CT scan. The purpose of this study is to describe the method of the technique and to identify the precise anatomy of jaw. We evaluated 13 mandibles and 7 maxillae of 15 subjects without bony disease who were being considered for endosseous dental implants. Reformatted images obtained by the use of bone algorithm performed on GE HiSpeed Advantage CT scanner were retrospectively reviewed for detailed anatomy of jaw. Anatomy related to neurovascular bundle(mandibular foramen, inferior alveolar canal, mental foramen, canal for incisive artery, nutrient canal, lingual foramen and mylohyoid groove), muscular insertion(mylohyoid line, superior and inferior genial tubercle and digastric fossa) and other anatomy(submandibular fossa, sublingual fossa, contour of alveolar process, oblique line, retromolar fossa, temporal crest and retromolar triangle) were well delineated in mandible. In maxilla, anatomy related to neurovascular bundle(greater palatine foramen and groove, nasopalatine canal and incisive foramen) and other anatomy(alveolar process, maxillary sinus and nasal fossa) were also well delineated. Reformatted images using dental CT software program provided excellent delineation of the jaw anatomy. Therefore, dental CT software program can play an important role in the preoperative assessment of mandible and maxilla for dental implants and other surgical conditions

[Systematic review and meta-analysis on the effect of implant supported overdentures on the oral health related quality of life of edentulous patients].

Science.gov (United States)

Zhang, S S; Zhang, Y; Di, P; Lin, Y

2017-05-09

Objective: To evaluate the effect of implant related treatment on the oral health related quality of life (OHRQoL) of edentulous patients. Methods: The CNKI, Wanfang database and Medline, EMBASE, Cochrane Library databases that include randomized clinical trials comparing implant supported overdentures with conventional complete denture for edentulous patients were retrived. Nine studies involving 769 cases were included and meta-analysis was conducted. Results: The standardized mean difference (SMD) of oral health impact profile (OHIP) score was 1.63 (95% CI: 1.25-2.02) and improved after implant related treatment, which was significantly better than the conventional complete denture (0.87, 95% CI: 0.54-1.20). Conclusions: Implant supported overdentures improved patient's OHRQoL and showed better performance compared to the overdentures complete dentures.

Jaw Dysfunction Related to Pterygoid and Masseter Muscle Dosimetry After Radiation Therapy in Children and Young Adults With Head-and-Neck Sarcomas

International Nuclear Information System (INIS)

Krasin, Matthew J.; Wiese, Kristin M.; Spunt, Sheri L.; Hua, Chia-ho; Daw, Najat; Navid, Fariba; Davidoff, Andrew M.; McGregor, Lisa; Merchant, Thomas E.; Kun, Larry E.; McCrarey, Lola

2012-01-01

Purpose: To investigate the relationship between jaw function, patient and treatment variables, and radiation dosimetry of the mandibular muscles and joints in children and young adults receiving radiation for soft-tissue and bone sarcomas. Methods and Materials: Twenty-four pediatric and young adult patients with head-and-neck sarcomas were treated on an institutional review board−approved prospective study of focal radiation therapy for local tumor control. Serial jaw depression measurements were related to radiation dosimetry delivered to the medial and lateral pterygoid muscles, masseter muscles, and temporomandibular joints to generate mathematical models of jaw function. Results: Baseline jaw depression was only influenced by the degree of surgical resection. In the first 12 weeks from initiation of radiation, surgical procedures greater than a biopsy, administration of cyclophosphamide containing chemotherapy regimes, and large gross tumor volumes adversely affected jaw depression. Increasing dose to the pterygoid and masseter muscles above 40 Gy predicted loss of jaw function over the full course of follow-up. Conclusions: Clinical and treatment factors are related to initial and subsequent jaw dysfunction. Understanding these complex interactions and the affect of specific radiation doses may help reduce the risk for jaw dysfunction in future children and young adults undergoing radiation therapy for the management of soft-tissue and bone sarcomas.

Jaw Dysfunction Related to Pterygoid and Masseter Muscle Dosimetry After Radiation Therapy in Children and Young Adults With Head-and-Neck Sarcomas

Energy Technology Data Exchange (ETDEWEB)

Krasin, Matthew J., E-mail: matthew.krasin@stjude.org [Department of Radiological Sciences, St. Jude Children' s Research Hospital, Memphis, TN (United States); Wiese, Kristin M. [Department of Rehabilitation Services, St. Jude Children' s Research Hospital, Memphis, TN (United States); Spunt, Sheri L. [Department of Oncology, St. Jude Children' s Research Hospital, Memphis, TN (United States); Department of Pediatrics, University of Tennessee College of Medicine, Memphis, TN (United States); Hua, Chia-ho [Department of Radiological Sciences, St. Jude Children' s Research Hospital, Memphis, TN (United States); Daw, Najat [Department of Pediatrics, University of Tennessee College of Medicine, Memphis, TN (United States); Department of Oncology, St. Jude Children' s Research Hospital, Memphis, TN (United States); Navid, Fariba [Department of Oncology, St. Jude Children' s Research Hospital, Memphis, TN (United States); Department of Pediatrics, University of Tennessee College of Medicine, Memphis, TN (United States); Davidoff, Andrew M. [Department of Surgery, St. Jude Children' s Research Hospital, Memphis, TN (United States); Department of Surgery, University of Tennessee College of Medicine, Memphis, TN (United States); McGregor, Lisa [Department of Oncology, St. Jude Children' s Research Hospital, Memphis, TN (United States); Department of Pediatrics, University of Tennessee College of Medicine, Memphis, TN (United States); Merchant, Thomas E.; Kun, Larry E. [Department of Radiological Sciences, St. Jude Children' s Research Hospital, Memphis, TN (United States); McCrarey, Lola [Department of Rehabilitation Services, St. Jude Children' s Research Hospital, Memphis, TN (United States); and others

2012-01-01

Purpose: To investigate the relationship between jaw function, patient and treatment variables, and radiation dosimetry of the mandibular muscles and joints in children and young adults receiving radiation for soft-tissue and bone sarcomas. Methods and Materials: Twenty-four pediatric and young adult patients with head-and-neck sarcomas were treated on an institutional review board-approved prospective study of focal radiation therapy for local tumor control. Serial jaw depression measurements were related to radiation dosimetry delivered to the medial and lateral pterygoid muscles, masseter muscles, and temporomandibular joints to generate mathematical models of jaw function. Results: Baseline jaw depression was only influenced by the degree of surgical resection. In the first 12 weeks from initiation of radiation, surgical procedures greater than a biopsy, administration of cyclophosphamide containing chemotherapy regimes, and large gross tumor volumes adversely affected jaw depression. Increasing dose to the pterygoid and masseter muscles above 40 Gy predicted loss of jaw function over the full course of follow-up. Conclusions: Clinical and treatment factors are related to initial and subsequent jaw dysfunction. Understanding these complex interactions and the affect of specific radiation doses may help reduce the risk for jaw dysfunction in future children and young adults undergoing radiation therapy for the management of soft-tissue and bone sarcomas.

A 5- to 8-year retrospective study comparing the clinical results of implant-supported telescopic crown versus bar overdentures in patients with edentulous maxillae.

Science.gov (United States)

Zou, Duohong; Wu, Yiqun; Huang, Wei; Zhang, Zhiyong; Zhang, Zhiyuan

2013-01-01

The objective of this study was to compare implant survival and success rates, peri-implant parameters, and prosthodontic maintenance efforts for implant-supported telescopic crown overdentures and bar overdentures to restore maxillary edentulism. This retrospective clinical study involved patients with maxillary edentulism who were fitted with implant-supported overdentures from January 2004 to June 2007. During a 5- to 8-year follow-up period, the implant survival and success rates, biologic and mechanical complications, prosthodontic maintenance, and patient satisfaction were retrospectively analyzed. The data were evaluated statistically and P overdentures. Twenty-one patients chose telescopic crown overdentures and 23 patients chose bar overdentures. A total of 41 patients and 201 implants were available for follow-up. The implant survival and success rates, average bone resorption, and subjective patient satisfaction scores showed no difference between the telescopic crown and the bar overdenture group at follow-up. However, there were higher values for Plaque and Calculus Indexes in the bar group compared with the telescopic crown group, and these values showed a statistically significant difference annually from the 3-year follow-up (P overdentures provided a healthy peri-implant structure for implants in both groups. Implant-supported telescopic crown or bar overdentures can provide a good treatment option for patients with edentulous maxillae.

Modulation of human exteroceptive jaw reflexes during simulated mastication

NARCIS (Netherlands)

Lobbezoo, F.; Sowman, P.F.; Türker, K.S.

2009-01-01

Objective: To investigate changes in synaptic input from lower lip afferents to human jaw muscle motoneurons during simulated mastication. Methods: The lower lip of 14 subjects was stimulated electrically under static and dynamic conditions. In the static condition, subjects bit at mid-open position

Manajemen Pelayanan Mahasiswa Difabel di PLD UIN Sunan Kalijaga Berbasis Komputer Job Access with Speech (JAWS

Directory of Open Access Journals (Sweden)

Kuzaemah

2017-05-01

Full Text Available This research attempt to meganalisis how management of computer service JAWS for student of blind at PLD UIN Sunan Kalijaga Yogyakarta. This research is a field research using qualitative approach. Data collection is done through observation, interview, and documentation. The results of this study indicate that JAWS Computer Service Management in PLD UIN Sunan Kalijaga Yogyakarta includes several management functions, the first, the planning of the PLD chairman determines the schedule of activities. Second, the organizing of the PLD chair divides the duties of each position. Third, the implementation of all PLD members who have been tasked by the leader perform their duties respectively. Fourth, supervision of all activities in the PLD is always monitored and held a regular meeting to find out the problems faced so that can be solved together. Benefits of the existence of JAWS computer service is to increase knowledge of technology for blind students and train the independence of blind students in doing lecture tasks that blessed with typing as well as paper assignments, thesis and so on. The factors supporting the implementation of JAWS computer service that is the spirit of learning blind students and the help of PLD volunteers. For the inhibiting factor is the number of JAWS computers are very limited so they have to take turns in using it

Msx-1 is suppressed in bisphosphonate-exposed jaw bone analysis of bone turnover-related cell signalling after bisphosphonate treatment.

Science.gov (United States)

Wehrhan, F; Hyckel, P; Amann, K; Ries, J; Stockmann, P; Schlegel, Ka; Neukam, Fw; Nkenke, E

2011-05-01

Bone-destructive disease treatments include bisphosphonates and antibodies against receptor activator for nuclear factor κB ligand (aRANKL). Osteonecrosis of the jaw (ONJ) is a side-effect. Aetiopathology models failed to explain their restriction to the jaw. The osteoproliferative transcription factor Msx-1 is expressed constitutively only in mature jaw bone. Msx-1 expression might be impaired in bisphosphonate-related ONJ. This study compared the expression of Msx-1, Bone Morphogenetic Protein (BMP)-2 and RANKL, in ONJ-affected and healthy jaw bone. An automated immunohistochemistry-based alkaline phosphatase-anti-alkaline phosphatase method was used on ONJ-affected and healthy jaw bone samples (n = 20 each): cell-number ratio (labelling index, Bonferroni adjustment). Real-time RT-PCR was performed to quantitatively compare Msx-1, BMP-2, RANKL and GAPDH mRNA levels. Labelling indices were significantly lower for Msx-1 (P Msx-1, 22-fold lower (P Msx-1, RANKL suppression and BMP-2 induction were consistent with the bisphosphonate-associated osteopetrosis and impaired bone remodelling in BP- and aRANKL-induced ONJ. Msx-1 suppression suggested a possible explanation of the exclusivity of ONJ in jaw bone. Functional analyses of Msx-1- RANKL interaction during bone remodelling should be performed in the future. © 2011 John Wiley & Sons A/S.

Implant and prosthodontic survival rates with implant fixed complete dental prostheses in the edentulous mandible after at least 5 years: a systematic review.

Science.gov (United States)

Papaspyridakos, Panos; Mokti, Muizzaddin; Chen, Chun-Jung; Benic, Goran I; Gallucci, German O; Chronopoulos, Vasilios

2014-10-01

The treatment of mandibular edentulism with implant fixed complete dental prostheses (IFCDPs) is a routinely used treatment option. The study aims to report the implant and prosthodontic survival rates associated with IFCDPs for the edentulous mandible after an observation period of a minimum 5 years. An electronic MEDLINE/PubMED search was conducted to identify randomized controlled clinical trials and prospective studies with IFCDPs for the edentulous mandible. Clinical studies with at least 5-year follow-up were selected. Pooled data were statistically analyzed and cumulative implant- and prosthesis survival rates were calculated by meta-analysis, regression, and chi-square statistics. Implant-related and prosthesis-related factors were identified and their impact on survival rates was assessed. Seventeen prospective studies, including 501 patients and 2,827 implants, were selected for meta-analysis. The majority of the implants (88.5% of all placed implants) had been placed in the interforaminal area. Cumulative implant survival rates for rough surface ranged from 98.42% (95% confidence interval [CI]: 97.98-98.86) (5 years) to 96.86% (95% CI: 96.00-97.73) (10 years); smooth surface implant survival rates ranged from 98.93% (95% CI: 98.38-99.49) (5 years) to 97.88% (95% CI: 96.78-98.98) (10 years). The prosthodontic survival rates for 1-piece IFCDPs ranged from 98.61% (95% CI: 97.80-99.43) (5 years) to 97.25% (95% CI: 95.66-98.86) (10 years). Treatment with mandibular IFCDPs yields high implant and prosthodontic survival rates (more than 96% after 10 years). Rough surface implants exhibited cumulative survival rates similar to the smooth surface ones (p > .05) in the edentulous mandible. The number of supporting implants and the antero-posterior implant distribution had no influence (p > .05) on the implant survival rate. The prosthetic design and veneering material, the retention type, and the loading protocol (delayed, early, and immediate) had no

Implant rehabilitation of the atrophic edentulous maxilla including immediate fixed provisional restoration without the use of bone grafting: a review of 1-year outcome data from a long-term prospective clinical trial.

Science.gov (United States)

Toljanic, Joseph A; Baer, Russell A; Ekstrand, Karl; Thor, Andreas

2009-01-01

The literature suggests that predictable integration can be achieved when dental implant placement is combined with immediate fixed provisional restoration in a variety of clinical situations. Fewer data are available, however, regarding outcomes for immediate provisional restoration of implants in the edentulous maxilla. This report presents 1-year data acquired from a long-term prospective clinical trial designed to assess outcomes following the immediate provisional fixed restoration of implants in the atrophic edentulous maxilla without the use of bone augmentation. Fifty-one subjects diagnosed with an atrophic edentulous maxilla received a total of 306 implants (six implants per subject) followed by fixed provisional restoration within 24 hours of implant placement. No subjects underwent grafting to enhance bone volume in preparation for implant treatment. Data acquired included bone quantity and quality, implant dimensions, implant locations, and implant placement stability. Subjects returned for 1-year follow-up examinations to assess implant integration and restoration function. Periapical radiographs were obtained and compared to baseline images to assess marginal bone height maintenance. At the 3-month follow-up examination, 294 of 306 implants placed in 51 subjects were found to be integrated. This represents a cumulative implant survival rate of 96%. At the 1-year follow-up examination, mean marginal bone loss of 0.5 mm was noted, with no further loss of implants. These results support the contention that predictable long-term outcomes may be obtained for the atrophic edentulous maxilla when treated with an implant rehabilitation protocol that includes immediate fixed provisional restoration without the use of bone grafting. This strategy offers a promising treatment alternative for the patient with an atrophic edentulous maxilla.

Diagnostic sensitivity and specificity in a retrospective clinical, radiographic and histopathological study of 166 cystic jaw lesions

DEFF Research Database (Denmark)

Therkildsen, N. M.; Andersen, Kristian; Blomlôf, J.

2014-01-01

, but a low diagnostic sensitivity in relation to the keratocystic odontogenic tumour (KCOT) was revealed. The radicular cyst, dentigerous cyst and KCOT were the most frequently observed cystic jaw lesions. Conclusion In general, a high diagnostic specificity for all cystic jaw lesions was observed. A low...

Experimental muscle pain produces central modulation of proprioceptive signals arising from jaw muscle spindles.

Science.gov (United States)

Capra, N F; Ro, J Y

2000-05-01

The aim of the present study was to investigate the effects of intramuscular injection with hypertonic saline, a well-established experimental model for muscle pain, on central processing of proprioceptive input from jaw muscle spindle afferents. Fifty-seven cells were recorded from the medial edge of the subnucleus interpolaris (Vi) and the adjacent parvicellular reticular formation from 11 adult cats. These cells were characterized as central units receiving jaw muscle spindle input based on their responses to electrical stimulation of the masseter nerve, muscle palpation and jaw stretch. Forty-five cells, which were successfully tested with 5% hypertonic saline, were categorized as either dynamic-static (DS) (n=25) or static (S) (n=20) neurons based on their responses to different speeds and amplitudes of jaw movement. Seventy-six percent of the cells tested with an ipsilateral injection of hypertonic saline showed a significant modulation of mean firing rates (MFRs) during opening and/or holding phases. The most remarkable saline-induced change was a significant reduction of MFR during the hold phase in S units (100%, 18/18 modulated). Sixty-nine percent of the DS units (11/16 modulated) also showed significant changes in MFRs limited to the hold phase. However, in the DS neurons, the MFRs increased in seven units and decreased in four units. Finally, five DS neurons showed significant changes of MFRs during both opening and holding phases. Injections of isotonic saline into the ipsilateral masseter muscle had little effect, but hypertonic saline injections made into the contralateral masseter muscle produced similar results to ipsilateral injections with hypertonic saline. These results unequivocally demonstrate that intramuscular injection with an algesic substance, sufficient to produce muscle pain, produces significant changes in the proprioceptive properties of the jaw movement-related neurons. Potential mechanisms involved in saline-induced changes in the

Overdenture retained by teeth using a definitive denture base technique: a case report.

Science.gov (United States)

Nascimento, D F F; dos Santos, J F F; Marchini, L

2010-09-01

This paper presents a technique involving the use of a definitive denture base to make overdentures. Cores with ball attachments were cemented over remaining lower teeth. Impressions of the edentulous maxilla and mandible were taken to obtain a definitive acrylic resin base. The definitive base of the mandible was perforated at the location of ball attachments and its female components were fixed to the base using acrylic resin directly in the patient's mouth. Wax rims were then made, jaw relationships recorded, teeth mounted and tried in, and the dentures were cured. This technique allowed for easy fixing of female components and better retention during the recording of jaw relationships, and can also be used in the construction of implant retained dentures.

Oral Health in Rural Communities

Science.gov (United States)

... people with partial edentulism when compared to urban (Urban, 38.4%, High Poverty Rural 51.3%, Other Rural, 45%). Counties with high rates of full edentulism are also rural (Urban, 4.3%, High-Poverty Rural 10.5%, Other Rural, 8.2%). ( Mitchell, ...

Immediate Loading of Implants in the Edentulous Maxilla with a Fixed Provisional Restoration without Bone Augmentation: A Report on 5-Year Outcomes Data Obtained from a Prospective Clinical Trial.

Science.gov (United States)

Toljanic, Joseph A; Ekstrand, Karl; Baer, Russell A; Thor, Andreas

2016-01-01

Successful immediate loading of implants in the edentulous maxilla has been previously reported. The purpose of this 5-year prospective study was to further assess long-term outcomes following immediate loading of implants in the edentulous maxilla with fixed provisional restorations without the use of bone augmentation procedures. Subjects with edentulous maxillary arches each received six implants placed in native bone without augmentation. Where insufficient posterior bone volume existed, angled implant placement was employed. Fixed provisional restorations were delivered within 24 hours of implant placement. Implant placement locations, insertion torque values, and implant dimensions were recorded. Definitive fixed prostheses were placed within 24 weeks following implantation. Baseline implant site marginal bone levels were measured using periapical radiographs. Baseline peri-implant plaque and bleeding scores were obtained. Subjects were examined 6 months after implant placement and then annually for 5 years with follow-up periapical radiographs and plaque/bleeding scores obtained. Fifty-one subjects received a total of 306 implants. Forty subjects with 232 implants returned for the final follow-up appointment representing a 5-year implant survival proportion of 93% with a mean marginal bone loss of 0.44 ± 1.25 mm for this group. Thirty-nine of these 40 subjects continued to function with fixed restorations with the remaining subject functioning with a non-implant-retained removable prosthesis. Within the limitations of this study, predictable long-term implant rehabilitation outcomes were demonstrated for the edentulous maxilla using an immediate loading protocol without bone augmentation.

Jaw lever analysis of Hawaiian gobioid stream fishes: a simulation study of morphological diversity and functional performance.

Science.gov (United States)

Maie, Takashi; Schoenfuss, Heiko L; Blob, Richard W

2009-08-01

Differences in feeding behavior and performance among the five native Hawaiian gobioid stream fishes (Sicyopterus stimpsoni, Lentipes concolor, Awaous guamensis, Stenogobius hawaiiensis, and Eleotris sandwicensis) have been proposed based on the skeletal anatomy of their jaws and dietary specialization. However, performance of the feeding apparatus likely depends on the proportions and configurations of the jaw muscles and the arrangement of the jaw skeleton. We used a published mathematical model of muscle function to evaluate potential differences in jaw closing performance and their correlations with morphology among these species. For example, high output force calculated for the adductor mandibulae muscles (A2 and A3) of both A. guamensis and E. sandwicensis matched expectations based on the morphology of these species because these muscles are larger than in the other species. In contrast, Stenogobius hawaiiensis exhibited an alternative morphological strategy for achieving high relative output forces of both A2 and A3, in which the placement and configuration of the muscles conveyed high mechanical advantage despite only moderate cross-sectional areas. These differing anatomical pathways to similar functional performance suggest a pattern of many-to-one mapping of morphology to performance. In addition, a functional differentiation between A2 and A3 was evident for all species, in which A2 was better suited for producing forceful jaw closing and A3 for rapid jaw closing. Thus, the diversity of feeding performance of Hawaiian stream gobies seems to reflect a maintenance of functional breadth through the retention of some primitive traits in combination with novel functional capacities in several species. (c) 2009 Wiley-Liss, Inc.

Implant-tooth-supported fixed partial prostheses: correlations between in vivo occlusal bite forces and marginal bone reactions.

Science.gov (United States)

Akça, Kivanç; Uysal, Serdar; Cehreli, Murat Cavit

2006-06-01

To evaluate maximal occlusal bite forces (MOF) and marginal bone level (MBL) changes in patients with implant-tooth-supported fixed partial prostheses (FPP). Twenty nine partially edentulous patients consecutively who received 34 three-occlusal unit FPP with terminal implant and tooth support were subjected to quantification of MOFs using a sub-miniature load cell connected to a data acquisition system and measurement of the MBL changes around implants in digitalized periapical radiographs obtained at prostheses delivery and 24-month follow-up. MOFs for implant support (mean: 353.61 N) significantly differed from tooth support (mean: 275.48 N) (P 0.05). MBL changes at mesial and distal sites of the implants at 24 months of functional loading were 0.28 and 0.097 mm respectively. Although MOFs under functional loading might indicate an increase in load participation for supporting implant, the rigid connection between implant and natural tooth via three-occlusal unit FPP does not jeopardize the time-dependent MBL stability of the implant under functional loads.

Use of personal computers for Gothic arch tracing: analysis and evaluation of horizontal mandibular positions with edentulous prosthesis.

Science.gov (United States)

Watanabe, Y

1999-11-01

Determining mandibular position for an edentulous patient raises the question of whether to emphasize centric relation or muscular position. This challenge results from the lack of a convenient procedure for quantifying the horizontal mandibular position, which can be determined by a variety of methods. This study analyzed and evaluated the horizontal mandibular positions produced by different guidance systems. Twenty-six edentulous subjects with no clinical evidence of abnormality of temporomandibular disorder were selected. Horizontal position data for the mandible obtained by gothic arch tracing was loaded into a personal computer by setting the sensor portion of a digitizer into the oral cavity to serve as a miniature lightweight tracing board. By connecting this with a digitizer control circuit set in an extraoral location, each mandibular position was displayed in a distinguishable manner on a computer display in real time, then recorded and analyzed. The gothic arch apex and tapping point varied, depending on body position. In the supine position, the gothic arch apex and the tapping point were close to the mandibular position determined by bilateral manipulation. This system provides effective data concerning mandibular positions for fabrication of dentures.

Evaluation of jaw and neck muscle activities while chewing using EMG-EMG transfer function and EMG-EMG coherence function analyses in healthy subjects.

Science.gov (United States)

Ishii, Tomohiro; Narita, Noriyuki; Endo, Hiroshi

2016-06-01

This study aims to quantitatively clarify the physiological features in rhythmically coordinated jaw and neck muscle EMG activities while chewing gum using EMG-EMG transfer function and EMG-EMG coherence function analyses in 20 healthy subjects. The chewing side masseter muscle EMG signal was used as the reference signal, while the other jaw (non-chewing side masseter muscle, bilateral anterior temporal muscles, and bilateral anterior digastric muscles) and neck muscle (bilateral sternocleidomastoid muscles) EMG signals were used as the examined signals in EMG-EMG transfer function and EMG-EMG coherence function analyses. Chewing-related jaw and neck muscle activities were aggregated in the first peak of the power spectrum in rhythmic chewing. The gain in the peak frequency represented the power relationships between jaw and neck muscle activities during rhythmic chewing. The phase in the peak frequency represented the temporal relationships between the jaw and neck muscle activities, while the non-chewing side neck muscle presented a broad range of distributions across jaw closing and opening phases. Coherence in the peak frequency represented the synergistic features in bilateral jaw closing muscles and chewing side neck muscle activities. The coherence and phase in non-chewing side neck muscle activities exhibited a significant negative correlation. From above, the bilateral coordination between the jaw and neck muscle activities is estimated while chewing when the non-chewing side neck muscle is synchronously activated with the jaw closing muscles, while the unilateral coordination is estimated when the non-chewing side neck muscle is irregularly activated in the jaw opening phase. Thus, the occurrence of bilateral or unilateral coordinated features in the jaw and neck muscle activities may correspond to the phase characteristics in the non-chewing side neck muscle activities during rhythmical chewing. Considering these novel findings in healthy subjects, EMG

The effect of food bolus location on jaw movement smoothness and masticatory efficiency.

Science.gov (United States)

Molenaar, W N B; Gezelle Meerburg, P J; Luraschi, J; Whittle, T; Schimmel, M; Lobbezoo, F; Peck, C C; Murray, G M; Minami, I

2012-09-01

Masticatory efficiency in individuals with extensive tooth loss has been widely discussed. However, little is known about jaw movement smoothness during chewing and the effect of differences in food bolus location on movement smoothness and masticatory efficiency. The aim of this study was to determine whether experimental differences in food bolus location (anterior versus posterior) had an effect on masticatory efficiency and jaw movement smoothness. Jaw movement smoothness was evaluated by measuring jerk-cost (calculated from acceleration) with an accelerometer that was attached to the skin of the mentum of 10 asymptomatic subjects, and acceleration was recorded during chewing on two-colour chewing gum, which was used to assessed masticatory efficiency. Chewing was performed under two conditions: posterior chewing (chewing on molars and premolars only) and anterior chewing (chewing on canine and first premolar teeth only). Jerk-cost and masticatory efficiency (calculated as the ratio of unmixed azure colour to the total area of gum, the unmixed fraction) were compared between anterior and posterior chewing with the Wilcoxon signed rank test (two-tailed). Subjects chewed significantly less efficiently during anterior chewing than during posterior chewing (P = 0·0051). There was no significant difference in jerk-cost between anterior and posterior conditions in the opening phase (P = 0·25), or closing phase (P = 0·42). This is the first characterisation of the effect of food bolus location on jaw movement smoothness at the same time as recording masticatory efficiency. The data suggest that anterior chewing decreases masticatory efficiency, but does not influence jerk-cost. © 2012 Blackwell Publishing Ltd.

Central Giant Cell Granuloma of the Jaws: Correlation between Vascularity and Biologic Behavior

Directory of Open Access Journals (Sweden)

Saede Atarbashi Moghadam

2017-03-01

Full Text Available Introduction: Giant cell lesions of the bone comprise a group of jaw bone pathologies. Different pathogeneses such as reactive, vascular or neoplastic have been proposed for these lesions. In addition, differentiating between aggressive and nonaggressive central giant cell granuloma (CGCG of the jaws based on histopathologic features is still impossible and due to different treatment protocols for the two groups, correct diagnosis is necessary. The purpose of this study was to compare the expression of CD34 between aggressive and nonaggressive CGCGs of the jaws. Methods & Materials: This retrospective study was carried out on 16 paraffin blocks in each aggressive and nonaggressive CGCGs group. The expression of CD34 was evaluated with immunohistochemical technique. Afterwards, t-test was used for quantitative evaluation and comparison of CD34 expression among the two groups. Eventually, statistical analysis was performed using Spss20 software. Significance was assigned at p < 0.05. Results: In the present study, the average age of patients in aggressive and nonaggressive groups was 20.93±8.08 and 26.18±16.97, respectively. In both groups, female predilection was observed. Mandible was the most common site of involvement in the aggressive group and the distribution of nonaggressive lesions was equal between both jaws. Although the expression of CD34 in the aggressive group was higher than the nonaggressive group, no statistically significant difference was seen (p=0.15. Conclusion: According to the results of the current study, it appears that CD34 protein cannot be used for identifying the clinical behavior of CGCGs.

Correlation of the Condylar Guidance Obtained by Protrusive Interocclusal Record and Panoramic Radiographs in Completely Edentulous Patients: An in Vivo Study

Directory of Open Access Journals (Sweden)

Khyati Shah

2014-01-01

Results: The results showed statistically significant difference between the condylar guidance values obtained from Orthopantomograph (Radiograph and the condylar guidance values obtained at the stage of jaw relation. Conclusion: Within the limitations of the study, it can be concluded that the condylar guidance values obtained from the Radiographs were higher than those obtained at the stage of jaw relation recording stage.

SU-E-T-346: Effect of Jaw Position On Dose to Critical Structures in 3-D Conformal Radiotherapy Treatment of Pancreatic Cancer

Energy Technology Data Exchange (ETDEWEB)

Paudel, N; Han, E; Liang, X; Morrill, S; Zhang, X; Hardee, M; Penagaricano, J; Ratanatharathorn, V [Vaneerat, University of Arkansas for Medical Sciences, Little Rock, AR (United States)

2015-06-15

Purpose: Three-dimensional conformal therapy remains a valid and widely used modality for pancreatic radiotherapy treatment. It usually meets dose constraints on critical structures. However, careful positioning of collimation jaws can reduce dose to the critical structures. Here we investigate the dosimetric effect of jaw position in MLC-based 3-D conformal treatment planning on critical structures. Methods: We retrospectively selected seven pancreatic cancer patients treated with 3-D conformal radiotherapy. We started with treatment plans (Varian Truebeam LINAC, Eclipse TPS, AAA, 18MV) having both x and y jaws aligned with the farthest extent of the block outline (8mm around PTV). Then we subsequently moved either both x-jaws or all x and y jaws outwards upto 3 cm in 1 cm increments and investigated their effect on average and maximum dose to neighboring critical structures keeping the same coverage to treatment volume. Results: Lateral displacement of both x-jaws by 1cm each increased kidney and spleen mean dose by as much as 1.7% and 1.3% respectively and superior inferior displacement increased liver, right kidney, stomach and spleen dose by as much as 2.1%, 2%, 5.2% and 1.6% respectively. Displacement of all x and y-jaws away by 1cm increased the mean dose to liver, right kidney, left kidney, bowels, cord, stomach and spleen by as much as 4.9%, 5.9%, 2.1%, 2.8%, 7.4%, 10.4% and 4.2% respectively. Percentage increase in mean dose due to 2 and 3cm jaw displacement increased almost linearly with the displaced distance. Changes in maximum dose were much smaller (mostly negligible) than the changes in mean dose. Conclusion: Collimation jaw position affects dose mostly to critical structures adjacent to it. Though treatment plans with MLCs conforming the block margin usually meet dose constraints to critical structures, keeping jaws all the way in, to the edge of the block reduces dose to the critical structures during radiation treatment.

Three-dimensional esthetic analysis in treatment planning for implant-supported fixed prosthesis in the edentulous maxilla: review of the esthetics literature.

Science.gov (United States)

Bidra, Avinash S

2011-08-01

Fixed implant-supported prosthesis for the edentulous maxilla has gained tremendous popularity over the years. Multiple prosthetic designs have been introduced in order to accommodate a gamut of clinical situations. Irrespective of the design, it is paramount that the esthetics imparted by the prosthesis be uncompromised. Though esthetics is subjective, a common ground exists where all its fundamental principles converge. This article reviews pertinent dental and facial esthetics literature for application of various esthetic concepts involved in diagnosis and treatment planning for an implant-supported fixed prosthesis in the edentulous maxilla. Three-dimensional esthetic analysis involves assessment of various esthetic parameters in superior-inferior, medial-lateral, and anterior-posterior dimensions. The impact of various esthetic parameters such as facial forms, facial profiles, maxillary teeth positions, maxillary teeth proportions, smile lines, lip support, gingival display, facial midline, dental midline, horizontal cant, and smile width are discussed in detail. © 2011 Wiley Periodicals, Inc.

Mandibular Flexure in Anterior-Posterior and Transverse Plane on Edentulous Patients in Mashhad Faculty of Dentistry

Directory of Open Access Journals (Sweden)

Azam Sadat Madani

2013-01-01

Full Text Available Introduction: Angle and internal position of lateral pterygoid muscle leads to contraction over two half of the mandible in maximum opening and protrusion position so it can affects impression prosthetic procedures. The aim of this study was to evaluate the mandibular flexure in two transverse and antro-posterior dimensions. Methods: Seventy edentulous patients at Mashhad Faculty of Dentistry as the main group and 50 dentulous patients as the control group were selected. In these patients, transverse dimensions between second molar areas and also canine eminence from one side to another side, and longitudinal dimensions based on the distance between canine to second molar area at centric occlusion and maximum mouth opening were measured. Dimensional differences as the mandibular flexure were measured. Results: The mandibular dimensions in maximum opening and closed mouth were different. Average reduction in transverse dimension on second molar region at maximum mouth opening and closing position were almost equal to -0.0787 mm for target group and 0.7512 mm for control group. On anterior side, averages of these changes were equal to 0.3069 mm for target group and were 0.2254 mm for control group. Conclusion: Transverse dimensions in anterior region at maximum opening position are smaller than the same dimension at closed mouth in edentulous and dentulous patients.

Assessment of the Survival of Dental Implants in Irradiated Jaws ...

African Journals Online (AJOL)

frequency of dental implant placement in irradiated jaws from. 2002 to 2008 in India. Table 2 ..... Linsen SS, Martini M, Stark H. Long-term results of endosteal implants following radical oral ... Oral Health 2015:5;1-6. 21. Visch LL, van Waas MA ...

Root canal therapy for the prevention of osteonecrosis of the jaws: an evidence-based clinical update.

Science.gov (United States)

Kyrgidis, Athanassios; Arora, Amit; Lyroudia, Kleoniki; Antoniades, Konstantinos

2010-12-01

Osteonecrosis of the jaws is an adverse effect of bone preservation treatment. There is a sufficient body of evidence to associate osteonecrosis of the jaws development with dental extractions and trauma caused from ill-fitting dentures. In this review, we critically appraise available evidence about the clinical efficacy of root canal therapy in patients receiving bisphosphonates.We review a series of theories to explain why endodontic treatment is a safe clinical intervention to prevent osteonecrosis of the jaws in patients receiving bisphosphonates. Root canal therapy could postpone or even eradicate the need for dental extractions of carious teeth in patients on bisphosphonates who may develop osteonecrosis of the jaws. Patients receiving bisphosphonates should be offered the full range of preventive care to reduce their risk to both dental caries and periodontal disease, so that the need for both endodontic therapy and dental extractions will be reduced. Implementing such a strategy would require both practitioner and patient education through the combined efforts of medical and dental societies. Such an approach is justified, as the risk of compromising the oral health of patients on bisphosphonates undertaking endodontic treatment is negligible compared with the benefit from avoiding dental extractions.

Modern trends in the conservative management of lower jaw radio-necrosis following radiotherapy for tongue cancer

International Nuclear Information System (INIS)

Dapkova, L.

1997-01-01

This is a report on radio-necrosis of the lower jaw developing after radiation treatment for tongue cancer. Brief literature data concerning lower jaw osteoradionecrosis are presented, including incidence rate, dependence on the type of irradiation and doses applied and overall therapeutic approach to the lesion. An original scheme for complex conservative management, consistent with the specific pathogenetic patterns of post-irradiation necrosis, promoting active osteogenesis is proposed. It includes: antibiotics (4 quinolines, metronidazole, lincomycin, cephalosporin, nystatin), local antiseptic drugs (gargle with camomile, sol. tripaflavini 2 per cent, borax-glycerin, sterile 10 per cent solution of sodium chloride and the like), Miacalcic (calcitonin), vitamin D2, calcium-phospho C, parenteral nutrition, vitamins, retabolil, analgesics (general and local). The scheme, used in three patients with lower jaw radio-necrosis developing after radiotherapy for lingual cancer, yields very good results - pain relief, disappearance of trismus, with nutrition and sleep returning to normal. After demarcation of the necrotic tissue, sequestrectomy is done with ensuing complete epithelization. Lower jaw integrity is preserved without any functional and cosmetic defects. The duration of treatment is 8, 4 and 2 months, respectively (author)

Multiple jaw cysts not associated with basal cell nevus syndrome

International Nuclear Information System (INIS)

Yoon, Suk Ja; Kang, Byung Cheol

2003-01-01

We present two cases of multiple jaw cysts not associated with basal cell nevus syndrome. Case 1 : a nine year-old boy visited CNU Hospital for orthodontic treatment and his radiographs showed cystic lesions surrounding the crowns of teeth 13 and 17 respectively, which were diagnosed as dentigerous cysts. Subsequently, two more cysts were found on his follow-up radiographs in 12 and 15 months. The two cysts were determined to be odontogenic keratocysts. The boy had no skeletal abnormalities and no skin lesions associated with basal cell nevus syndrome. Case 2: a fifty-eight year old man had three impacted third molars with pericoronal radiolucencies, which were diagnosed as dentigerous cysts. He had no additional abnormalities associated with basal cell nevus syndrome. Multiple jaw cysts can occur at any age, and periodic radiographic surveillance may be needed for any cases of impacted tooth.

Effect of Repeated Food Morsel Splitting on Jaw Muscle Control

DEFF Research Database (Denmark)

A, Kumar; Svensson, Krister G; Baad-Hansen, Lene

2014-01-01

Mastication is a complex motor task often initiated by splitting of the food morsel between the anterior teeth. Training of complex motor tasks has consistently been shown to trigger neuroplastic changes in corticomotor control and optimization of muscle function. It is not known if training...... and repeated food morsel splitting lead to changes in jaw muscle function. Objective: To investigate if repeated splitting of food morsels in participants with natural dentition changes the force and jaw muscle electromyographic (EMG) activity. Methods: Twenty healthy volunteers (mean age = 26.2 ± 3.9 years......) participated in a single one-hour session divided into six series. Each series consisted of ten trials of a standardized behavioral task (total of 60 trials). The behavioral task was to hold and split a food morsel (8 mm, 180 mg placebo tablet) placed on a bite force transducer with the anterior teeth...

Multiple jaw cysts not associated with basal cell nevus syndrome

Energy Technology Data Exchange (ETDEWEB)

Yoon, Suk Ja; Kang, Byung Cheol [Chonnam National University College of Medicine, Kwangju (Korea, Republic of)

2003-09-15

We present two cases of multiple jaw cysts not associated with basal cell nevus syndrome. Case 1 : a nine year-old boy visited CNU Hospital for orthodontic treatment and his radiographs showed cystic lesions surrounding the crowns of teeth 13 and 17 respectively, which were diagnosed as dentigerous cysts. Subsequently, two more cysts were found on his follow-up radiographs in 12 and 15 months. The two cysts were determined to be odontogenic keratocysts. The boy had no skeletal abnormalities and no skin lesions associated with basal cell nevus syndrome. Case 2: a fifty-eight year old man had three impacted third molars with pericoronal radiolucencies, which were diagnosed as dentigerous cysts. He had no additional abnormalities associated with basal cell nevus syndrome. Multiple jaw cysts can occur at any age, and periodic radiographic surveillance may be needed for any cases of impacted tooth.

Comparative evaluation of computed tomography for dental implants on the mandibular edentulous area

Energy Technology Data Exchange (ETDEWEB)

Sun, Kyung Hoon; Jeong, Ho Gul; Park, Hyok; Park, Chang Seo; Kim, Kee Deog [Department of Oral and Maxillofacial Radiology, Oral Science Research Center, College of Dentistry, Yonsei University, Seoul (Korea, Republic of)

2009-03-15

The purpose of this study was to evaluate the clinical usefulness of the recently developed multi-detector computed tomography and cone beam computed tomography in pre-operative implant evaluation, by comparing them with the single detector computed tomography, already confirmed for accuracy in this area. Five partially edentulous dry human mandibles, with 1 X 1 mm gutta percha cones, placed in 5 mm intervals posterior to the mental foramen on each side of the buccal part of the mandible, were used in this study. They were scanned as follows: 1) Single detector computed tomography: slice thickness 1 mm, 200 mA, 120 kV 2) Multi-detector computed tomography: slice thickness 0.75 mm, 250 mA, 120 kV 3) Cone beam computed tomography: 15 mAs, 120 kV Axial images acquired from three computed tomographs were transferred to personal computer, and then reformatted cross-sectional images were generated using V-Implant 2.0 (CyberMed Inc., Seoul, Korea) software. Among the cross-sectional images of the gutta percha cone, placed in the buccal body of the mandible, the most precise cross section was selected as the measuring point and the distance from the most superior border of the mandibular canal to the alveolar crest was measured and analyzed 10 times by a dentist. There were no significant intraobserver differences in the distance from the most superior border of the mandibular canal to the alveolar crest (p>0.05). There were no significant differences among single detector computed tomography, multi-detector computed tomography and cone beam computed tomography in the distance from the most superior border of the mandibular canal to the alveolar crest (p>0.05). Multi-detector computed tomography and cone beam computed tomography are clinically useful in the evaluation of pre-operative site for mandibular dental implants, with consideration for radiation exposure dose and scanning time.

Comparative evaluation of computed tomography for dental implants on the mandibular edentulous area

International Nuclear Information System (INIS)

Sun, Kyung Hoon; Jeong, Ho Gul; Park, Hyok; Park, Chang Seo; Kim, Kee Deog

2009-01-01

The purpose of this study was to evaluate the clinical usefulness of the recently developed multi-detector computed tomography and cone beam computed tomography in pre-operative implant evaluation, by comparing them with the single detector computed tomography, already confirmed for accuracy in this area. Five partially edentulous dry human mandibles, with 1 X 1 mm gutta percha cones, placed in 5 mm intervals posterior to the mental foramen on each side of the buccal part of the mandible, were used in this study. They were scanned as follows: 1) Single detector computed tomography: slice thickness 1 mm, 200 mA, 120 kV 2) Multi-detector computed tomography: slice thickness 0.75 mm, 250 mA, 120 kV 3) Cone beam computed tomography: 15 mAs, 120 kV Axial images acquired from three computed tomographs were transferred to personal computer, and then reformatted cross-sectional images were generated using V-Implant 2.0 (CyberMed Inc., Seoul, Korea) software. Among the cross-sectional images of the gutta percha cone, placed in the buccal body of the mandible, the most precise cross section was selected as the measuring point and the distance from the most superior border of the mandibular canal to the alveolar crest was measured and analyzed 10 times by a dentist. There were no significant intraobserver differences in the distance from the most superior border of the mandibular canal to the alveolar crest (p>0.05). There were no significant differences among single detector computed tomography, multi-detector computed tomography and cone beam computed tomography in the distance from the most superior border of the mandibular canal to the alveolar crest (p>0.05). Multi-detector computed tomography and cone beam computed tomography are clinically useful in the evaluation of pre-operative site for mandibular dental implants, with consideration for radiation exposure dose and scanning time.

Determination of capacity of single-toggle jaw crusher, taking into account parameters of kinematics of its working mechanism

Science.gov (United States)

Golikov, N. S.; Timofeev, I. P.

2018-05-01

Efficiency increase of jaw crushers makes the foundation of rational kinematics and stiffening of the elements of the machine possible. Foundation of rational kinematics includes establishment of connection between operation mode parameters of the crusher and its technical characteristics. The main purpose of this research is just to establish such a connection. Therefore this article shows analytical procedure of getting connection between operation mode parameters of the crusher and its capacity. Theoretical, empirical and semi-empirical methods of capacity determination of a single-toggle jaw crusher are given, taking into account physico-mechanical properties of crushed material and kinematics of the working mechanism. When developing a mathematical model, the method of closed vector polygons by V. A. Zinoviev was used. The expressions obtained in the article give an opportunity to solve important scientific and technical problems, connected with finding the rational kinematics of the jaw crusher mechanism, carrying out a comparative assessment of different crushers and giving the recommendations about updating the available jaw crushers.

[Florid cemento-osseous dysplasia of the jaws].

Science.gov (United States)

Benazzou, S; Boulaadas, M; El Ayoubi, A; Nazih, N; Essakalli, L; Kzadri, M

2011-06-01

Florid cemento-osseous dysplasia is a benign and rare tumor of the jaws. It is more commonly seen in middle-aged black women. Most cases are asymptomatic and are found during routine radiographic examination. We report two complicated cases of florid cemento-osseous dysplasia, one with facial deformity and the other with chronic osteitis. The diagnosis of florid cemento-osseous dysplasia is based on clinical and radiological features. The lesions are commonly bilateral and symmetrical. Copyright © 2011. Published by Elsevier Masson SAS.

Pattern and polarity in the development and evolution of the gnathostome jaw: both conservation and heterotopy in the branchial arches of the shark, Scyliorhinus canicula.

Science.gov (United States)

Compagnucci, Claudia; Debiais-Thibaud, Melanie; Coolen, Marion; Fish, Jennifer; Griffin, John N; Bertocchini, Federica; Minoux, Maryline; Rijli, Filippo M; Borday-Birraux, Véronique; Casane, Didier; Mazan, Sylvie; Depew, Michael J

2013-05-15

The acquisition of jaws constitutes a landmark event in vertebrate evolution, one that in large part potentiated their success and diversification. Jaw development and patterning involves an intricate spatiotemporal series of reciprocal inductive and responsive interactions between the cephalic epithelia and the cranial neural crest (CNC) and cephalic mesodermal mesenchyme. The coordinated regulation of these interactions is critical for both the ontogenetic registration of the jaws and the evolutionary elaboration of variable jaw morphologies and designs. Current models of jaw development and evolution have been built on molecular and cellular evidence gathered mostly in amniotes such as mice, chicks and humans, and augmented by a much smaller body of work on the zebrafish. These have been partnered by essential work attempting to understand the origins of jaws that has focused on the jawless lamprey. Chondrichthyans (cartilaginous fish) are the most distant group to amniotes within extant gnathostomes, and comprise the crucial clade uniting amniotes and agnathans; yet despite their critical phylogenetic position, evidence of the molecular and cellular underpinnings of jaw development in chondrichthyans is still lacking. Recent advances in genome and molecular developmental biology of the lesser spotted dogfish shark, Scyliorhinus canicula, make it ideal for the molecular study of chondrichthyan jaw development. Here, following the 'Hinge and Caps' model of jaw development, we have investigated evidence of heterotopic (relative changes in position) and heterochronic (relative changes in timing) shifts in gene expression, relative to amniotes, in the jaw primordia of S. canicula embryos. We demonstrate the presence of clear proximo-distal polarity in gene expression patterns in the shark embryo, thus establishing a baseline molecular baüplan for branchial arch-derived jaw development and further validating the utility of the 'Hinge and Caps' model in comparative

The biological basis of treating jaw discrepancies: An interplay of mechanical forces and skeletal configuration.

Science.gov (United States)

Karamesinis, Konstantinos; Basdra, Efthimia K

2018-05-01

Jaw discrepancies and malrelations affect a large proportion of the general population and their treatment is of utmost significance for individuals' health and quality of life. The aim of their therapy is the modification of aberrant jaw development mainly by targeting the growth potential of the mandibular condyle through its cartilage, and the architectural shape of alveolar bone through a suture type of structure, the periodontal ligament. This targeted treatment is achieved via external mechanical force application by using a wide variety of intraoral and extraoral appliances. Condylar cartilage and sutures exhibit a remarkable plasticity due to the mechano-responsiveness of the chondrocytes and the multipotent mesenchymal cells of the sutures. The tissues respond biologically and adapt to mechanical force application by a variety of signaling pathways and a final interplay between the proliferative activity and the differentiation status of the cells involved. These targeted therapeutic functional alterations within temporo-mandibular joint ultimately result in the enhancement or restriction of mandibular growth, while within the periodontal ligament lead to bone remodeling and change of its architectural structure. Depending on the form of the malrelation presented, the above treatment approaches, in conjunction or separately, lead to the total correction of jaw discrepancies and the achievement of facial harmony and function. Overall, the treatment of craniofacial and jaw anomalies can be seen as an interplay of mechanical forces and adaptations occurring within temporo-mandibular joint and alveolar bone. The aim of the present review is to present up-to-date knowledge on the mechano-biology behind jaw growth modification and alveolar bone remodeling. Furthermore, future molecular targeted therapeutic strategies are discussed aiming at the improvement of mechanically-driven chondrogenesis and osteogenesis. Copyright © 2018 Elsevier B.V. All rights reserved.

Solitary Intra-Osseous Myofibroma of the Jaw: A Case Report and Review of Literature

Directory of Open Access Journals (Sweden)

Anita Dhupar

2017-10-01

Full Text Available Myofibroma is a rare benign spindle cell neoplasm in children that usually affects both soft tissue and bone in the head and neck region. Approximately one third of these cases are seen within jaw bones as solitary lesions. Solitary intra-osseous myofibroma of the jaw bone shares its clinical, radiographic and histological features with other spindle cell tumors. The rarity of this lesion can make diagnosis difficult for clinicians and pathologists. We report a case of a solitary intra-osseous myofibroma in the mandible of a nine-year-old child.

"Converting a bi-jaw surgery to a single-jaw surgery:" Posterior maxillary dentoalveolar intrusion with microimplants to avoid the need of a maxillary surgery in the surgical management of skeletal Class III vertical malocclusion

Directory of Open Access Journals (Sweden)

Abhisek Ghosh

2016-01-01

Full Text Available The management of a vertical skeletal Class III malocclusion with mandibular prognathism revolves around the protocol of bi-jaw surgery (maxillary LeFort I impaction and mandibular bilateral sagittal split osteotomy with setback. The maxillary surgery not only provides increased stability to the ultimate surgical outcome but also increases the amount by which the mandibular set back can be done, therefore aiding in greater profile improvement. With the need of maxillary surgery almost inevitable in treating such situations, the complexity and the increased discomfort associated with such surgery can never be ignored. Is it at all possible to convert a bi-jaw surgery into a single-jaw surgery with the aid of microimplants? With increasing number of patients being treated with microimplants for anterior openbite and gummy smiles, our idea was to incorporate this novel protocol in treating Class III vertical situations and therefore avoid the need of a maxillary surgery in treating such a situation, together with achieving optimum treatment outcome.

Jaws calibration method to get a homogeneous distribution of dose in the junction of hemi fields

International Nuclear Information System (INIS)

Cenizo de Castro, E.; Garcia Pareja, S.; Moreno Saiz, C.; Hernandez Rodriguez, R.; Bodineau Gil, C.; Martin-Viera Cueto, J. A.

2011-01-01

Hemi fields treatments are widely used in radiotherapy. Because the tolerance established for the positioning of each jaw is 1 mm, may be cases of overlap or separation of up to 2 mm. This implies heterogeneity of doses up to 40% in the joint area. This paper presents an accurate method of calibration of the jaws so as to obtain homogeneous dose distributions when using this type of treatment. (Author)

Influence of Implant Position on Stress Distribution in Implant-Assisted Distal Extension Removable Partial Dentures: A 3D Finite Element Analysis.

Science.gov (United States)

Memari, Yeganeh; Geramy, Allahyar; Fayaz, Amir; Rezvani Habib Abadi, Shirin; Mansouri, Yasaman

2014-09-01

Distal extension removable partial denture is a prosthesis with lack of distal dental support with a 13-fold difference in resiliency between the mucosa and the periodontal ligament, resulting in leverage during compression forces. It may be potentially destructive to the abutments and the surrounding tissues. The aim of this study was to assess the effect of implant location on stress distribution, in distal extension implant assisted removable partial dentures. Three-dimensional models of a bilateral distal extension partially edentulous mandible containing anterior teeth and first premolar in both sides of the arch, a partial removable denture and an implant (4×10mm) were designed. With the aid of the finite element program ANSYS 8.0, the models were meshed and strictly vertical forces of 10 N were applied to each cusp tip. Displacement and von Mises Maps were plotted for visualization of results. When an implant was placed in the second premolar region, the highest stress on implant, abutment tooth and cancellous bone was shown. The lowest stress was shown on implant and bone in the 1(st) molar area. Implants located in the first molar area showed the least distribution of stresses in the analyzed models.

A fixed-jaw method to protect critical organs during intensity-modulated radiotherapy

International Nuclear Information System (INIS)

Chen, Jiayun; Chen, Xinyuan; Huang, Manni; Dai, Jianrong

2014-01-01

Intensity-modulated radiotherapy (IMRT) plays an important role in cancer radiotherapy. For some patients being treated with IMRT, the extremely low tolerances of critical organs (such as lens, ovaries, and testicles) cannot be met during treatment planning. The aim of this article is to introduce a new planning method to overcome that problem. In current planning practice, jaw positions are automatically set to cover all target volumes by the planning system (e.g., Pinnacle 3 system). Because of such settings, critical organs may be fully blocked by the multileaf collimator (MLC), but they still sit in the field that is shaped by collimator jaws. These critical organs receive doses from the transmission and leakage of MLC leaves. We manually fixed jaw positions to block them to further reduce such doses. This method has been used for different treatment sites in our clinic, and it was thoroughly evaluated in patients with radical hysterectomy plus ovarian transposition after surgery. For each patient, 2 treatment plans were designed with the same optimization parameters: the original plan with automatically chosen jaw positions (called O-plan) and the plan with fixed-jaw positions (named F-plan). In the F-plan, the jaws were manually fixed to block the ovaries. For target coverage, the mean conformity index (CI) of the F-plan (1.28 ± 0.02) was remarkably lower than that of the O-plan (1.53 ± 0.09) (p < 0.05). The F-plan and the O-plan performed similarly in target dose homogeneity. Meanwhile, for the critical organ sparing, the mean dose of both ovaries were much lower in the F-plan than that in the O-plan (p < 0.05). The V 20 , V 30 , and V 40 of bladder were also lower in the F-plan (93.57 ± 1.98, 73.99 ± 5.76, and 42.33 ± 3.7, respectively) than those in the O-plan (97.98 ± 1.11, 85.07 ± 4.04, and 49.71 ± 3.63, respectively) (p < 0.05). The maximum dose to the spinal cord planning organ at risk (OAR) volume (PRV) in the O-plan (3940.24 ± 102.8) was

Social capital and oral health: The association of social capital with edentulism and chewing ability in the rural elderly.

Science.gov (United States)

Kim, Eun-Kyong; Jung, Yun-Sook; Kim, Kyung-Hee; Kim, Ki-Rim; Kwon, Gi-Hong; Choi, Youn-Hee; Lee, Hee-Kyung

2018-01-01

The association between social capital and oral health had been reported in various ways, but still remains unclear. We investigated the association between the social capital of the elderly living in a rural region and their edentulism and chewing ability. A total of 241 elderly aged≥70years living in a rural city of Korea participated in this cross-sectional study. Their social capital was surveyed by questionnaire assessing its network and trust dimensions. Their edentulism and chewing ability were assessed by oral examination and chewing gum whose color changes based on the mastication performance. The mean age of the participants was 82.7 (ranged 71 to 101) years and 68.8% of them were female. In the binomial regression analysis, the general network aspect of the network dimension was significantly associated with chewing ability, of which the prevalence ratio was 1.88 (95% CI: 1.16-3.06) in the age, sex, education and marital status-adjusted model. Our findings suggest that social capital, such as a poor social network, is associated with poor chewing ability in the elderly living in rural areas. Copyright © 2017 Elsevier B.V. All rights reserved.

Effect of Gamma Radiation sterilization versus Disinfection on Removable Partial Dentures (Microbiological study)

International Nuclear Information System (INIS)

Mohammed, M.A.

2011-01-01

The aim of the study was to compare between the effectiveness of disinfection, using commercially available Fittydent super cleansing tablets versus sterilization, using gamma radiation on candidal growth in maxillary removable partial dentures. Methods: Fourteen partially edentulous subjects were selected according to specific criteria and divided equally and randomly into two groups; Group I: disinfection group and Group II: sterilization group. Conventional maxillary removable partial dentures were constructed for all subjects. The swab technique was used to collect the samples one month after denture delivery, immediately after disinfection/sterilization, and then one week, two weeks, three weeks, four weeks, and five weeks after disinfection/sterilization respectively. Bacteriological candidal colony count was performed using a manual contact colony counter. Results: Both methods (disinfection and sterilization) led to a noticeable decrease in the candidal count. However this decrease was highly and markedly evident in Group II as compared to Group I. Infact, no candidal growth was recorded for group II immediately after strerilization and was maintained for two more weeks. Statistical analysis revealed highly significant differences between the two groups. Conclusions: Both methods were effective in decreasing the number of Candida albicans adhering to the denture. However, sterilization using Gamma radiation had a more superior immediate, as well as, long term efficiency as compared to disinfection using Fittydent super cleansing tablets.

Esthetic considerations for the treatment of the edentulous maxilla based on current informatic alternatives: a case report.

Science.gov (United States)

Rodríguez-Tizcareño, Mario H; Barajas, Lizbeth; Pérez-Gásque, Marisol; Gómez, Salvador

2012-06-01

This report presents a protocol used to transfer the virtual treatment plan data to the surgical and prosthetic reality and its clinical application, bone site augmentation with computer-custom milled bovine bone graft blocks to their ideal architecture form, implant insertion based on image-guided stent fabrication, and the restorative manufacturing process through computed tomography-based software programs and navigation systems and the computer-aided design and manufacturing techniques for the treatment of the edentulous maxilla.

Classification system on the selection of number of implants and superstructure design on the basis available vertical restorative space and interforaminal distance for implant supported mandibular overdenture

Directory of Open Access Journals (Sweden)

Akshay Bhargava

2016-01-01

Full Text Available Purpose: The rehabilitation of the edentulous mandible is a challenge due to various limiting factors, of which the available vertical restorative space (AVRS has been well understood in the literature. However, other anatomic variations such as arch form, arch size, and also the interforaminal distance (IFD (due to the presence of mandibular nerve are influential in the selection of size and position of implants, and thereby the prosthetic design. Materials and Method: In the present study, 30 edentulous patients from a group of 300 edentulous patients, representing all the three jaw relations (Class I, II, and III were evaluated for designing a classification that could help in a comprehensive treatment plan for the edentulous mandible. Dental panoramic radiographs of each individual with a trial or final prosthesis were made. The horizontal IFD and AVRS values were calculated. Results: One-way analysis of variance followed by post-hoc test (multiple comparison and Bonferroni method having P < 0.05 as significant value showed an overall mean of 38.9 mm for horizontal distance and 13.69 mm for the AVRS in 30 edentulous patients. Conclusion: The results showed that in the majority of cases (90% there is insufficient space to place a bar attachment supported by five implants for mandibular overdentures. This suggests that a universal treatment plan cannot be followed due to varying anatomic factors. Hence, it becomes imperative to have a set of clinical guidelines based on the AVRS and IFD, for the selection of implant number and type of attachment. The article proposes a simple classification system based on the AVRS and IFD for establishing guidelines in the treatment planning of the edentulous mandible, to aid in selection of implant size, number, and position along with the associated prosthetic design.

[Acupuncture combined with magnetic therapy for treatment of temple-jaw joint dysfunction].

Science.gov (United States)

Wang, Xiao-Hui; Zhang, Wen

2009-04-01

To compare clinical therapeutic effects of acupuncture combined with magnetic therapy and simple magnetic therapy on temple-jaw joint dysfunction. Eighty-two cases were randomly divided into an observation group (n = 52) and a control group (n = 30). The observation group was treated with acupuncture at Xiaguan (ST 7), Jiache (ST 6), Hegu (LI 4), etc. and AL-2 low frequency electromagnetic comprehensive treatment instrument; the control group was treated with AL-2 low frequency electromagnetic comprehensive treatment instrument. The cured and markedly effective rate of 90.4% in the observation group was significantly better than 66.7% in the control group (P magnetic therapy is significantly better than that of the simple magnetic therapy on temple-jaw joint dysfunction.

Bisphosphonate-associated Osteonecrosis of the jaws and endodontic treatment: two case reports.

Science.gov (United States)

Goodell, Gary

2006-01-01

Bisphosphonates are commonly used in the management of bone diseases, such as osteoporosis and Paget's disease, and to prevent bone complications and treat malignant hypercalcemia in certain types of cancer. Although this class of drugs has clear evidence of medical efficacy, there are an, increasing number of reports of bisphosphonate-associated osteonecrosis of the jaws that have substantial implications for the patient and for the treating dentist. This article reviews proposed possible mechanisms of bisphosphonate-associated osteonecrosis of the jaws and describes two case reports where non-surgical and surgical root canal treatment were precipitating factors. Recommendations for prevention and treatment of the disease follow. Thorough history-taking and timely consultation with the patient's oral surgeon and oncologist are emphasized.

[The clinical and X-ray classification of osteonecrosis of the low jaw].

Science.gov (United States)

Medvedev, Iu A; Basin, E M; Sokolina, I A

2013-01-01

To elaborate a clinical and X-ray classification of osteonecrosis of the low jaw in people with desomorphine or pervitin addiction. Ninety-two patients with drug addiction who had undergone orthopantomography, direct frontal X-ray of the skull, and multislice computed tomography, followed by multiplanar and three-dimensional imaging reconstruction were examined. One hundred thirty four X-ray films and 74 computed tomographic images were analyzed. The authors proposed a clinical and X-ray classification of osteonecrosis of the low jaw in people with desomorphine or pervitin addiction and elaborated recommendations for surgical interventions on the basis of the developed classification. The developed clinical and X-ray classification and recommendations for surgical interventions may be used to treat osteonecroses of various etiology.

Osteonecrosis of the jaw: a rare and devastating side effect of bisphosphonates.

LENUS (Irish Health Repository)

Ryan, P

2009-12-01

Evidence has emerged that bisphosphonate use in cancer patients is associated with osteonecrosis of the jaw. This form of osteonecrosis has been termed bisphosphonate induced osteonecrosis of the jaw (BIONJ). BIONJ is commonly precipitated by a tooth extraction in patients treated with long term, potent, high dose intravenous bisphosphonates for the management of myeloma, breast or prostate cancer. The overall prevalence of BIONJ is about 5% in patients with these malignancies. Current evidence shows that the risk of BIONJ in non-cancerous patients, such as those with osteoporosis, is very low and appears to be comparable with that of the general population. Prescribing physicians need to encourage cancer patients to see their dentists before the initiation of bisphosphonate treatment, and regularly thereafter.

Raman Spectroscopic Analyses of Jaw Periosteal Cell Mineralization

Directory of Open Access Journals (Sweden)

Eva Brauchle

2017-01-01

Full Text Available To achieve safer patient treatments, serum-free cell culture conditions have to be established for cell therapies. In previous studies, we demonstrated that serum-free culture favored the proliferation of MSCA-1+ osteoprogenitors derived from the jaw periosteum. In this study, the in vitro formation of bone-specific matrix by MSCA-1+ jaw periosteal cells (JPCs, 3 donors was assessed and compared under serum-free and serum-containing media conditions using the marker-free Raman spectroscopy. Based on a standard fluorescence assay, JPCs from one patient were not able to mineralize under serum-containing culture conditions, whereas the other cells showed similar mineralization levels under both conditions. Raman spectra from mineralizing MSCA-1+ JPCs revealed higher levels of hydroxyapatite formation and higher mineral to matrix ratios under serum-free culture conditions. Higher carbonate to phosphate ratios and higher crystallinity in JPCs cultured under serum-containing conditions indicated immature bone formation. Due to reduced collagen production under serum-free conditions, we obtained significant differences in collagen maturity and proline to hydroxyproline ratios compared to serum-free conditions. We conclude that Raman spectroscopy is a useful tool for the assessment and noninvasive monitoring of in vitro mineralization of osteoprogenitor cells. Further studies should extend this knowledge and improve JPC mineralization by optimizing culture conditions.

Measurements on the movement of the lower jaw in speech

NARCIS (Netherlands)

Nooteboom, S.G.; Slis, I.H.

1970-01-01

This report concerns some preliminary measurements on the movement of the lower jaw in speech. Such measurements may be interesting for several reasons. One of these is that they more easily than measurements on the movements of other articulators may give some insight into the effect of stress,

Assessment of the survival of dental implants in irradiated jaws ...

African Journals Online (AJOL)

Background: In patients undergoing head and neck surgery for various pathologic conditions, implants are one of the best restorative options and are increasing widely used. Therefore, we evaluated the success of dental implants in the irradiated jaws of patients following treatment of oral cancer oral cancer treated patients ...

Time to onset of bisphosphonate-related osteonecrosis of the jaws

DEFF Research Database (Denmark)

Fung, Ppl; Bedogni, G; Bedogni, A

2017-01-01

OBJECTIVES: Osteonecrosis of the jaw (ONJ) is a potentially severe adverse effect of bisphosphonates (BP). Although the risk of ONJ increases with increasing duration of BP treatment, there are currently no reliable estimates of the ONJ time to onset (TTO). The objective of this study was to esti...

Orofacial pain, jaw function, and temporomandibular disorders in adult women with a history of juvenile chronic arthritis or persistent juvenile chronic arthritis

DEFF Research Database (Denmark)

Bakke, M.; Zak, M.; Jensen, B.L.

2001-01-01

Orofacial pain, jaw function, temporomandibular disorders, adult women persistent juvenil chronic arthritis......Orofacial pain, jaw function, temporomandibular disorders, adult women persistent juvenil chronic arthritis...

Influence of connection type on the biomechanical behavior of distal extension mandibular removable partial dentures supported by implants and natural teeth.

Science.gov (United States)

Xiao, Wei; Li, Zhiyong; Shen, Shiqian; Chen, Shaowu; Chen, Sulin; Wang, Jiawei

2016-02-01

Few studies are performed to evaluate the influence of connection type on the stress distribution of distal extension mandibular removable partial dentures (RPDs) supported by both implants and natural teeth. In this study, five three-dimensional finite element models were prepared to simulate mandibular bilateral partially edentulous arches. Four were RPDs supported by both implants and natural teeth, and the other one was RPDs supported only by natural teeth. The maximum equivalent (EQV) stress values of bone around implants, the abutments, and the mucosa displacements of the related supporting structures were measured. It was found that a non-rigid telescopic coping was more favorable to protect the implant than a rigid telescopic coping. Compared with other connection types, the easy resilient attachment (ERA) system seemed to be effective to associate implant without complications. However, the results obtained in the present study should be cautiously interpreted in the clinic.

Selection of osteoprogenitors from the jaw periosteum by a specific animal-free culture medium.

Directory of Open Access Journals (Sweden)

Dorothea Alexander

Full Text Available The goal of our research work is to establish mesenchymal osteoprogenitors derived from human jaw periosteum for tissue engineering applications in oral and maxillofacial surgery. For future autologous and/or allogeneic transplantations, some issues must be addressed. On the one hand, animal-free culture conditions have yet to be established. On the other hand, attempts should be undertaken to shorten the in vitro culturing process efficiently. The aim of the present study is to compare and analyze the phenotype of osteoprogenitors from the jaw periosteum under normal FCS-containing and animal-free culture conditions. Therefore, we analyzed the proliferation rates of MesenCult-XF medium (MC- in comparison to DMEM-cultured JPCs. Whereas jaw periosteal cells (JPCs show relatively slow proliferation rates and a fibroblastoid shape under DMEM culture conditions, MC-cultured JPCs diminished their cell size significantly and proliferated rapidly. By live-monitoring measurements of adhesion and proliferation, we made an interesting observation: whereas the proliferation of the MSCA-1(+ subpopulation and the unseparated cell fraction were favored by the animal-free culture medium, the proliferation of the MSCA-1(- subpopulation seemed to be repressed under these conditions. The alkaline phosphatase expression pattern showed similar results under both culture conditions. Comparison of the mineralization capacity revealed an earlier formation of calcium-phosphate precipitates under MC culture conditions; however, the mineralization capacity of the DMEM-cultured cells seemed to be higher. We conclude that the tested animal-free medium is suitable for the in vitro expansion and even for the specific selection of osteoprogenitor cells derived from the jaw periosteum.

Comparative analysis of salivary bacterial microbiome diversity in edentulous infants and their mothers or primary care givers using pyrosequencing.

Directory of Open Access Journals (Sweden)

Kimberly D Cephas

Full Text Available Bacterial contribution to oral disease has been studied in young children, but there is a lack of data addressing the developmental perspective in edentulous infants. Our primary objectives were to use pyrosequencing to phylogenetically characterize the salivary bacterial microbiome of edentulous infants and to make comparisons against their mothers. Saliva samples were collected from 5 edentulous infants (mean age = 4.6±1.2 mo old and their mothers or primary care givers (mean age = 30.8±9.5 y old. Salivary DNA was extracted, used to generate DNA amplicons of the V4-V6 hypervariable region of the bacterial 16S rDNA gene, and subjected to 454-pyrosequencing. On average, over 80,000 sequences per sample were generated. High bacterial diversity was noted in the saliva of adults [1012 operational taxonomical units (OTU at 3% divergence] and infants (578 OTU at 3% divergence. Firmicutes, Proteobacteria, Actinobacteria, and Fusobacteria were predominant bacterial phyla present in all samples. A total of 397 bacterial genera were present in our dataset. Of the 28 genera different (P<0.05 between infants and adults, 27 had a greater prevalence in adults. The exception was Streptococcus, which was the predominant genera in infant saliva (62.2% in infants vs. 20.4% in adults; P<0.05. Veillonella, Neisseria, Rothia, Haemophilus, Gemella, Granulicatella, Leptotrichia, and Fusobacterium were also predominant genera in infant samples, while Haemophilus, Neisseria, Veillonella, Fusobacterium, Oribacterium, Rothia, Treponema, and Actinomyces were predominant in adults. Our data demonstrate that although the adult saliva bacterial microbiome had a greater OTU count than infants, a rich bacterial community exists in the infant oral cavity prior to tooth eruption. Streptococcus, Veillonella, and Neisseria are the predominant bacterial genera present in infants. Further research is required to characterize the development of oral microbiota early in life

Immediately loaded implants supporting fixed prostheses in the edentulous maxilla: a preliminary clinical and radiologic report.

Science.gov (United States)

Bergkvist, Göran; Sahlholm, Sten; Karlsson, Ulf; Nilner, Krister; Lindh, Christina

2005-01-01

To evaluate the survival rate of immediately loaded ITI sand-blasted, large-grit, acid-etched (SLA) solid-screw dental implants in the edentulous maxilla after 8 months of loading. Twenty-eight patients (mean age 63 years) with edentulous maxillae each received 6 implants and 1 implant-supported fixed provisional prosthesis within 24 hours after surgery. After a mean healing time of 15 weeks, the patient received a definitive, screw-retained, implant-supported fixed prosthesis. A total of 168 implants were placed. Clinical parameters were registered after 1 month of loading with the implant-supported fixed prostheses as well as 8 months after implant placement. Radiologic examinations and assessments were made at implant placement and after 8 months. The mean marginal bone level at implant placement was 1.6 mm (range 0 to 5.1; SD 1.1) apical of the reference point (the implant shoulder). The mean marginal bone level at the 8-month follow-up was 3.2 mm (range 0.4 to 5.9; SD 1.1) apical of the reference point. Three implants failed during the healing period. The improved results in the present study might be a result of the positive effect of splinting the implants immediately after placement. ITI SLA solid-screw implants immediately loaded (ie, loaded within 24 hours of placement) and supporting fixed prostheses had successful survival rates after 8 months. The present results constitute a solid baseline for future follow-up studies.

A description on pharyngeal jaw apparatus and diets of halfbeak fish Zenarchopterus buffonis (Valenciennes 1847) in Malaysian waters

Science.gov (United States)

Abidin, Diana Atiqah Zainal; Hashim, Marina; Das, Simon K.; Ghaffar, Mazlan Abd.

2015-09-01

Information on the feeding mechanism and diet of halfbeak fish species in harsh estuarine environment ecosystem is still lacking. The present study investigates the fine structure of pharyngeal jaw apparatus and diets of halfbeak fish Zenarchopterus buffonis. A total of 84 halfbeak fish samples have been collected from the coastal water of Peninsular Malaysia using fishing rod. Scanning electron microscopy was used to examine the micrographs of fine microstructure of the pharyngeal teeth. The fundamental anatomy of pharyngeal jaw apparatus displayed that the upper pharyngeal jaw (third pharyngobranchials) displays larger size of hook-like or tricuspid teeth which was analogous to tricuspid morphology. The lower pharyngeal jaw (fifth ceratobranchial) bears mainly conical teeth and appears triangular shape with two, short projections. The estimated TROPH values (1 - 3.2±0.55) denoted that halfbeak fish were omnivores in nature. The findings of this study was found to be useful as a baseline information for a better representation of the trophic flows associated with large medium and small surface water fishes.

A description on pharyngeal jaw apparatus and diets of halfbeak fish Zenarchopterus buffonis (Valenciennes 1847) in Malaysian waters

International Nuclear Information System (INIS)

Abidin, Diana Atiqah Zainal; Hashim, Marina; Ghaffar, Mazlan Abd.; Das, Simon K.

2015-01-01

Information on the feeding mechanism and diet of halfbeak fish species in harsh estuarine environment ecosystem is still lacking. The present study investigates the fine structure of pharyngeal jaw apparatus and diets of halfbeak fish Zenarchopterus buffonis. A total of 84 halfbeak fish samples have been collected from the coastal water of Peninsular Malaysia using fishing rod. Scanning electron microscopy was used to examine the micrographs of fine microstructure of the pharyngeal teeth. The fundamental anatomy of pharyngeal jaw apparatus displayed that the upper pharyngeal jaw (third pharyngobranchials) displays larger size of hook-like or tricuspid teeth which was analogous to tricuspid morphology. The lower pharyngeal jaw (fifth ceratobranchial) bears mainly conical teeth and appears triangular shape with two, short projections. The estimated TROPH values (1 − 3.2±0.55) denoted that halfbeak fish were omnivores in nature. The findings of this study was found to be useful as a baseline information for a better representation of the trophic flows associated with large medium and small surface water fishes

A description on pharyngeal jaw apparatus and diets of halfbeak fish Zenarchopterus buffonis (Valenciennes 1847) in Malaysian waters

Energy Technology Data Exchange (ETDEWEB)

Abidin, Diana Atiqah Zainal, E-mail: diana.atiqah@gmail.com; Hashim, Marina; Ghaffar, Mazlan Abd., E-mail: magfish05@yahoo.com [School of Environmental and Natural Resource Sciences, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor (Malaysia); Das, Simon K. [Marine Ecosystem Research Centre, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi (Malaysia)

2015-09-25

Information on the feeding mechanism and diet of halfbeak fish species in harsh estuarine environment ecosystem is still lacking. The present study investigates the fine structure of pharyngeal jaw apparatus and diets of halfbeak fish Zenarchopterus buffonis. A total of 84 halfbeak fish samples have been collected from the coastal water of Peninsular Malaysia using fishing rod. Scanning electron microscopy was used to examine the micrographs of fine microstructure of the pharyngeal teeth. The fundamental anatomy of pharyngeal jaw apparatus displayed that the upper pharyngeal jaw (third pharyngobranchials) displays larger size of hook-like or tricuspid teeth which was analogous to tricuspid morphology. The lower pharyngeal jaw (fifth ceratobranchial) bears mainly conical teeth and appears triangular shape with two, short projections. The estimated TROPH values (1 − 3.2±0.55) denoted that halfbeak fish were omnivores in nature. The findings of this study was found to be useful as a baseline information for a better representation of the trophic flows associated with large medium and small surface water fishes.

An unusual case of osteonecrosis of the jaw associated with dengue fever and periodontitis.

Science.gov (United States)

Indurkar, M S; Sethi, R

2016-03-01

Osteonecrosis is a disorder rarely occurring in the jaw. Dengue fever is a common mosquito-borne disease prevalent in many countries including India. The following report presents an interesting case of maxillary osteonecrosis in a middle aged male with a history of dengue infection. We also diagnosed symptoms of chronic periodontitis, which may have potentiated the necrosis. This case report will describe a novel clinical presentation and management of osteonecrosis of the jaw (ONJ) of unknown origin and a possible pathogenesis explaining the association of ONJ with dengue fever and periodontitis. © 2015 Australian Dental Association.

Jaw Osteomyelitis as a Complication of Sickle Cell Anaemia in Three Omani Patients; Case reports and literature review

Directory of Open Access Journals (Sweden)

Hilal Al-Ismaili

2017-03-01

Full Text Available Sickle cell anaemia (SCA is a common haemoglobinopathy among people from the Middle East, the Afro-Caribbean region, the Mediterranean and East India. While osteomyelitis of the long bones is a welldocumented complication of SCA, there are few documented cases of SCA patients presenting with jaw osteomyelitis. We report three SCA patients with chronic jaw osteomyelitis who presented to the Department of Oral Health, Sultan Qaboos University Hospital, Muscat, Oman, between 2009 and 2013. Two of the patients had osteomyelitis of the mandible and the third had osteomyelitis of the maxilla. In addition, a brief review of the literature is presented focusing on the clinical presentation, diagnosis and management of jaw osteomyelitis among patients with SCA.

Unicystic Jaw Lesions: A Radiographic Guideline

Directory of Open Access Journals (Sweden)

Giju George

2010-01-01

Full Text Available The unilocular radiolucencies remain the topic of much interest for the clinicians and histhopathologists for decades. Adequate use of diagnostic aids and careful observation will clinically help the dentist to arrive at a proper diagnosis and renders quality treatment to patients. Despite of the development of various cross-sectional imaging modalities, the radiograph still remains as the first and most important investigation. Jaw bone lesions, especially unilocular ones, are difficult to diagnose radiologically because of their similar radiographic appearance. It is, thus, very important for the clinician to have a sound knowledge of various radiographic features of the tooth and its supporting structures.

Effect of stimulus parameters and contraction level on inhibitory responses in human jaw-closing muscles: Implications for contingent stimulation

DEFF Research Database (Denmark)

Jadidi, F; Wang, K; Arendt-Nielsen, Lars

2009-01-01

  Objective: Examine the effect of stimulus duration as well as stimulus intensity and level of muscle contraction on the inhibitory responses in human jaw-closing muscles. Design: The inhibitory jaw-reflexes, ES1 and ES2, were recorded in the surface electromyogram (EMG) of masseter and temporal...

Self-Controlling Rig for Jaw Crusher Assembly

OpenAIRE

Saurabh Jadhav; Anup Pawar

2017-01-01

The aim of the work is to develop a method for easy assembly of the bearing in the housing by standardized way. The assembly of bearing should take place on the atomized set up. Based on this method a assembly setup was constructed which enables to assembly of the shaft with bearing of different models of jaw crusher. First tests were done with manual alignment and it shows that with proper alignment shaft assembly is very easy operation and also safe. Results of those tests show that the dev...

The jaw is a second-class lever in Pedetes capensis (Rodentia: Pedetidae

Directory of Open Access Journals (Sweden)

Philip G. Cox

2017-08-01

Full Text Available The mammalian jaw is often modelled as a third-class lever for the purposes of biomechanical analyses, owing to the position of the resultant muscle force between the jaw joint and the teeth. However, it has been proposed that in some rodents the jaws operate as a second-class lever during distal molar bites, owing to the rostral position of the masticatory musculature. In particular, the infraorbital portion of the zygomatico-mandibularis (IOZM has been suggested to be of major importance in converting the masticatory system from a third-class to a second-class lever. The presence of the IOZM is diagnostic of the hystricomorph rodents, and is particularly well-developed in Pedetes capensis, the South African springhare. In this study, finite element analysis (FEA was used to assess the lever mechanics of the springhare masticatory system, and to determine the function of the IOZM. An FE model of the skull of P. capensis was constructed and loaded with all masticatory muscles, and then solved for biting at each tooth in turn. Further load cases were created in which each masticatory muscle was removed in turn. The analyses showed that the mechanical advantage of the springhare jaws was above one at all molar bites and very close to one during the premolar bite. Removing the IOZM or masseter caused a drop in mechanical advantage at all bites, but affected strain patterns and cranial deformation very little. Removing the ZM had only a small effect on mechanical advantage, but produced a substantial reduction in strain and deformation across the skull. It was concluded that the masticatory system of P. capensis acts as a second class lever during bites along almost the entire cheek tooth row. The IOZM is clearly a major contributor to this effect, but the masseter also has a part to play. The benefit of the IOZM is that it adds force without substantially contributing to strain or deformation of the skull. This may help explain why the

Fibrous dysplasia of the jaws associated with secondary hyperparathyroidism: a case report

International Nuclear Information System (INIS)

Whi, Jung Hyun; Kim, Young Joo; Chun, Kyung Ah; Kim, Ki Tae; Chang, Eun Deok; Kim, Young Ok; Lee, Won

2007-01-01

There have been few reports on fibrous dyplasia associated with secondary hyperparathyroidism. We report a case of a hemodialysis patient with secondary hyperparathyroidism concomitant with fibrous dysplasia of the jaws causing an abnormal deformity

Evaluation of mandibular bone mineral density using the dual-energy X-ray absorptiometry technique in edentulous subjects living in an endemic fluorosis region.

Science.gov (United States)

Buyukkaplan, U S; Guldag, M U

2012-07-01

Fluoride is one of the biological trace elements with a strong affinity for osseous, cartilaginous and dental tissue. The dental and skeletal effects of high fluoride intake have already been studied in the literature, but little is known about the effects of high fluoride intake on edentulous mandibles. The purpose of this study was to evaluate the effects of high fluoride intake on mandibular bone mineral density (BMD) measured by the dual-energy X-ray absorptiometry (DXA) technique in edentulous individuals with systemic fluorosis. 32 people who were living in an endemic fluorosis area since birth and 31 people who were living in a non-endemic fluorosis area since birth (control group) participated in this study. Systemic fluorosis was diagnosed in the patients using the sialic acid (NANA)/glycosaminoglycan (GAG) ratio. The BMDs of the mandibles were determined by the DXA technique. The serum NANA/GAG ratios in the fluorosis group were significantly lower than those in the control group (p structures of the stomatognathic system.

Effect of implant support on mandibular distal extension removable partial dentures: relationship between denture supporting area and stress distribution.

Science.gov (United States)

Sato, Maki; Suzuki, Yasunori; Kurihara, Daisuke; Shimpo, Hidemasa; Ohkubo, Chikahiro

2013-04-01

This study explored the relationship between implant support and the denture-supporting area by comparing the stability of an implant-supported distal extension removable partial denture and a conventional distal extension removable partial denture. A model simulating a mandibular bilateral distal extension missing (#34-37 and #44-47) was fabricated using silicone impression material as soft tissue (2 mm thick) on an epoxy resin bone model. The denture base was reduced by 5 mm cutting part of both the retromolar pad and the lingual border. Loads of up to 5 kg were applied, and the pressure and displacement of the RPDs were simultaneously measured and analyzed using the Wilcoxon test (αremovable partial denture (ISRPD) was significantly less than on the conventional RPD (CRPD). As the supporting area of the denture base decreased, the pressure and the denture displacement of the CRPD were greater than for the ISRPD. This study indicated that implant placement at the distal edentulous ridge can prevent denture displacement of the distal extension bases, regardless of the supporting area of the denture base. Copyright © 2013 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.

Fetal jaw movement affects Ihh signaling in mandibular condylar cartilage development: the possible role of Ihh as mechanotransduction mediator.

Science.gov (United States)

Jahan, Esrat; Matsumoto, Akihiro; Rafiq, Ashiq Mahmood; Hashimoto, Ryuju; Inoue, Takayuki; Udagawa, Jun; Sekine, Joji; Otani, Hiroki

2014-10-01

Jaw movement is an important mechanical factor for prenatal development of the condylar cartilage of mandible. Fetal jaw movement restriction has been shown to cause deformity of the mandibular condyle. We hypothesized that this treatment affects the expression of mechanosensitive molecules, namely Indian hedgehog (Ihh) and Parathyroid hormone related protein (PTHrP) in the condyle. We restrained jaw movement by suturing the jaw of E15.5 mouse embryos and allowed them to develop until E18.5 using exo utero system, and analyzed them by immunohistochemistry and in situ hybridization methods. Morphological, histomorphometric and immunohistochemical study showed that the mandibular condylar cartilage was reduced and deformed, the volume and total cell numbers in the condylar cartilage were also reduced, and number and/or distribution of 5-bromo-2'-deoxyuridine-positive cells, Ihh-positive cells in the mesenchymal and pre-hypertrophic zones were significantly and correspondingly decreased in the sutured group. Using in situ hybridization, reduced expression of Ihh, PTHrP and their related receptors were observed in condylar cartilage of the sutured embryos. Our results revealed that the altered mechanical stress induced by prenatal jaw movement restriction decreased proliferating cells, the amount of cartilage, and altered expression of the Ihh and PTHrP, suggesting that Ihh act as mechanotransduction mediators in the development of mandibular condylar cartilage. Copyright © 2014 Elsevier Ltd. All rights reserved.

Influence of botulinum toxin on rabbit jaw muscle activity and anatomy

NARCIS (Netherlands)

Korfage, J.A.M.; Wang, J.; Lie, S.H.J.T.J.; Langenbach, G.E.J.

2012-01-01

Introduction: Muscles can adapt their fiber properties to accommodate to new conditions. We investigated the extent to which a decrease in muscle activation can cause an adaptation of fiber properties in synergistic and antagonistic jaw muscles. Methods: Three months after the injection of botulinum

Evaluation of stress patterns produced by implant-retained overdentures and implant-retained fixed partial denture.

Science.gov (United States)

Mazaro, José Vitor Quinelli; Filho, Humberto Gennari; Vedovatto, Eduardo; Pellizzer, Eduardo Piza; Rezende, Maria Cristina Rosifini Alves; Zavanelli, Adriana Cristina

2011-11-01

The purposes of this study were to photoelastically measure the biomechanical behavior of 4 implants retaining different cantilevered bar mandibular overdenture designs and to compare a fixed partial denture (FPD). A photoelastic model of a human edentulous mandible was fabricated, which contained 4 screw-type implants (3.75 × 10 mm) embedded in the parasymphyseal area. An FPD and 3 overdenture designs with the following attachments were evaluated: 3 plastic Hader clips, 1 Hader clip with 2 posterior resilient cap attachments, and 3 ball/O-ring attachments. Vertical occlusal forces of 100 N were applied between the central incisor and unilaterally to the right and left second premolars and second molars. Stresses that developed in the supporting structure were monitored photoelastically and recorded photographically. The results showed that the anterior loading, the overdenture with 3 plastic Hader clips, displayed the largest stress concentration at the medium implant. With premolar loading, the FPD and overdenture with 3 plastic Hader clips displayed the highest stresses to the ipsilateral terminal implant. With molar loading, the overdenture with 3 ball/O-ring attachments displayed the most uniform stress distribution in the posterior edentulous ridge, with less overloading in the terminal implant. It was concluded that vertical forces applied to the bar-clip overdenture and FPD created immediate stress patterns of greater magnitude and concentration on the ipsilateral implants, whereas the ball/O-ring attachments transferred minimal stress to the implants. The increased cantilever in the FPD caused the highest stresses to the terminal implant.

A feasibility study of using conventional jaws to deliver complex IMRT plans for head and neck cancer

International Nuclear Information System (INIS)

Mu, G; Xia, P

2009-01-01

Previous studies have demonstrated that simple intensity-modulated radiotherapy (IMRT) plans can be produced with a series of rectangular segments formed by conventional jaws. This study investigates whether complex IMRT plans for head and neck cancer can be delivered with the conventional jaws efficiently. Six nasopharyngeal cancer patients, previously treated with multi-leaf collimator (MLC)-IMRT plans, were re-planned using conventional jaw delivery options. All IMRT plans were subject to the plan acceptance criteria of the RTOG-0225 protocol. For a selected patient, the maximum number of segments varied from five to nine per beam, and was tested for both jaws-only IMRT (JO-IMRT) plans and MLC-IMRT plans. Subsequently, JO-IMRT plans and MLC-IMRT on the same treatment planning system were attempted for all patients with identical beams. The dose distribution, dose volume histograms (DVH), the conformal index (COIN), the uniformity index and delivery efficiency were compared between the MLC-IMRT and JO-IMRT plans. All JO-IMRT plans met the RTOG-0225 criteria for tumor coverage and sensitive structures sparing. The corresponding MLC-IMRT and JO-IMRT plans show comparable conformality and uniformity, with average COINs of the planning gross tumor volume(pGTV) 37.7% ± 18.7% versus 37.9% ± 18.1%, and the average uniformity index 82.8% ± 2.5% versus 83.6% ± 3.1%, respectively. The average monitor unit for JO-IMRT plans was about twice that of MLC-IMRT plans. In conclusion, conventional jaws can be used solely to deliver complex IMRT plans for patients with nasopharyngeal cancer yet still within a practical delivery time.

SU-E-T-394: The Use of Jaw Tracking in Intensity Modulated and Volumetric Modulated Arc Radiotherapy for Spine Stereotactic Radiosurgery

Energy Technology Data Exchange (ETDEWEB)

Chin, K; Wen, N; Huang, Y; Kim, J; Zhao, B; Siddiqui, S; Chetty, I; Ryu, S [Henry Ford Health System, Detroit, MI (United States)

2014-06-01

Purpose: To evaluate the potential advantages of jaw tracking for intensity modulated radiotherapy (IMRT) and volumetric modulated arc therapy (VMAT) in spine radiosurgery. Methods: VMAT and IMRT plans were retrospectively generated for ten patients. Six plans for each patient were created in the Eclipse treatment planning system for a Varian Truebeam equipped with a Millennium 120 MLC. Plans were created to study IMRT and VMAT plans with and without jaw tracking, as well as IMRT plans of different flattening filter free (FFF) energies. Plans were prescribed to the 90% isodose line to 16 or 18 Gy in one fraction to cover 95% of the target. Planning target volume (PTV) coverage, conformity index (CI), dose to spinal cord, distance to fall off from the 90% to 50% isodose line (DTF), as well as delivery time were evaluated. Ion chamber and film measurements were performed to verify calculated and measured dose distributions. Results: Jaw tracking decreased the spinal cord dose for both IMRT and VMAT plans, but a larger decrease was seen with the IMRT plans (p=0.004 vs p=0.04). The average D10% for the spinal cord was least for the 6MV FFF IMRT plan with jaw tracking and was greatest for the 10MV FFF plan without jaw tracking. Treatment times between IMRT and VMAT plans with or without jaw tracking were not significantly different. Measured plans showed greater than 98.5% agreement for planar dose gamma analysis (3%/2 mm) and less than 2.5% for point dose analysis compared to calculated plans. Conclusion: Jaw tracking can be used to help decrease spinal cord dose without any change in treatment delivery or calculation accuracy. Lower dose to the spinal cord was achieved using 6 MV beams compared to 10 MV beams, though 10 MV may be justified in some cases to decrease skin dose.

SU-E-T-394: The Use of Jaw Tracking in Intensity Modulated and Volumetric Modulated Arc Radiotherapy for Spine Stereotactic Radiosurgery

International Nuclear Information System (INIS)

Chin, K; Wen, N; Huang, Y; Kim, J; Zhao, B; Siddiqui, S; Chetty, I; Ryu, S

2014-01-01

Purpose: To evaluate the potential advantages of jaw tracking for intensity modulated radiotherapy (IMRT) and volumetric modulated arc therapy (VMAT) in spine radiosurgery. Methods: VMAT and IMRT plans were retrospectively generated for ten patients. Six plans for each patient were created in the Eclipse treatment planning system for a Varian Truebeam equipped with a Millennium 120 MLC. Plans were created to study IMRT and VMAT plans with and without jaw tracking, as well as IMRT plans of different flattening filter free (FFF) energies. Plans were prescribed to the 90% isodose line to 16 or 18 Gy in one fraction to cover 95% of the target. Planning target volume (PTV) coverage, conformity index (CI), dose to spinal cord, distance to fall off from the 90% to 50% isodose line (DTF), as well as delivery time were evaluated. Ion chamber and film measurements were performed to verify calculated and measured dose distributions. Results: Jaw tracking decreased the spinal cord dose for both IMRT and VMAT plans, but a larger decrease was seen with the IMRT plans (p=0.004 vs p=0.04). The average D10% for the spinal cord was least for the 6MV FFF IMRT plan with jaw tracking and was greatest for the 10MV FFF plan without jaw tracking. Treatment times between IMRT and VMAT plans with or without jaw tracking were not significantly different. Measured plans showed greater than 98.5% agreement for planar dose gamma analysis (3%/2 mm) and less than 2.5% for point dose analysis compared to calculated plans. Conclusion: Jaw tracking can be used to help decrease spinal cord dose without any change in treatment delivery or calculation accuracy. Lower dose to the spinal cord was achieved using 6 MV beams compared to 10 MV beams, though 10 MV may be justified in some cases to decrease skin dose

Bisphosphonates-induced osteonecrosis of the jaw: pharmacology and clinical procedures.

Directory of Open Access Journals (Sweden)

Candice Belchior Duplat

2012-01-01

Full Text Available Osteonecrosis of the jaw is a consequent condition of a variety of local and systemic factors that compromises the bone blood flow. Bisphosphonates are a class of compounds widely used for the treatment of disorders of bone metabolism, such as bone metastasis and osteoporosis. Bisphosphonates-induced osteonecrosis of the jaw is a new complication, published for the first time at 2003, and can be defined as an unexpected necrosis development on the oral cavity in patients who received bisphosphonates and were not being treated with head and neck radiotherapy. Radiographies show radiolucent zones or sclerotic bone and, in some cases, show areas with delayed or absent bone remodeling after extraction, remain the socket cavity. The treatment can be done in accordance with the condition stage, since management of 0,12% chlorhexidine and antibiotics until laser utilization, hyperbaric oxygen, surgical debridement and resection. It is important to promote more communication between physicians and dentists to guarantee dental attention during the bisphosphonate administration, establishing oral health and preventing complications, such as osteonecrosis induced by this medication.

BISPHOSPHONATES-INDUCED OSTEONECROSIS OF THE JAW: PHARMACOLOGY AND CLINICAL PROCEDURES.

Directory of Open Access Journals (Sweden)

Candice Belchior Duplat

2012-08-01

Full Text Available Osteonecrosis of the jaw is a consequent condition of a variety of local and systemic factors that compromises the bone blood flow. Bisphosphonates are a class of compounds widely used for the treatment of disorders of bone metabolism, such as bone metastasis and osteoporosis. Bisphosphonates-induced osteonecrosis of the jaw is a new complication, published for the first time at 2003, and can be defined as an unexpected necrosis development on the oral cavity in patients who received bisphosphonates and were not being treated with head and neck radiotherapy. Radiographies show radiolucent zones or sclerotic bone and, in some cases, show areas with delayed or absent bone remodeling after extraction, remain the socket cavity. The treatment can be done in accordance with the condition stage, since management of 0,12% chlorhexidine and antibiotics until laser utilization, hyperbaric oxygen, surgical debridement and resection. It is important to promote more communication between physicians and dentists to guarantee dental attention during the bisphosphonate administration, establishing oral health and preventing complications, such as osteonecrosis induced by this medication.

Analysis of the Single Toggle Jaw Crusher Force Transmission Characteristics

Directory of Open Access Journals (Sweden)

Moses Frank Oduori

2016-01-01

Full Text Available This paper sets out to perform a static force analysis of the single toggle jaw crusher mechanism and to obtain the force transmission characteristics of the mechanism. In order to obtain force transmission metrics that are characteristic of the structure of the mechanism, such influences as friction, dead weight, and inertia are considered to be extraneous and neglected. Equations are obtained by considering the balance of forces at the moving joints and appropriately relating these to the input torque and the output torque. A mechanical advantage, the corresponding transmitted torque, and the variations thereof, during the cycle of motion of the mechanism, are obtained. The mechanical advantage that characterizes the mechanism is calculated as the mean value over the active crushing stroke of the mechanism. The force transmission characteristics can be used as criteria for the comparison of different jaw crusher mechanism designs in order to select the most suitable design for a given application. The equations obtained can also be used in estimating the forces sustained by the components of the mechanism.

Kinematics and Mechanics analysis of trap-jaw ant Odontomachus monticola

Science.gov (United States)

Hao, Wenteng; Yao, Guang; Zhang, Xiangyu; Zhang, Deyuan

2018-03-01

Trap-jaw ants of the genus Odontomachus exhibit spectacularly rapid predatory and fugitive strikes. In order to reveal the extraordinary impact resistance of the apical teeth material, we analyzed the kinematics and mechanics of the closing mandibles. Odontomachus monticola is an Odontomachus species and extensive in China. We video-recorded jaw-strikes to measure the closing velocity and acceleration. The experimental results showed that O. monticola’s mandibles closed at a highest velocity of 35.42 m/s and a highest acceleration of 750,000 m/s2 within an average duration of 0.16 ms. In addition, in order to measure the strike force, we developed an extraordinary measuring method with poly (vinylidene fluoride) (PVDF) piezoelectric film. First, the dynamic calibration of the PVDF piezoelectric film was conducted, then the calibrated piezoelectric film was struck by O. monticola. Finally, the mandible strike force was calculated according to the calibration result and the output signal. The measurements results demonstrated that the strike force ranges from 102.2 N to 235.2 N, which is impressive contrast with O. monticola’s body weight.

Survival of various implant-supported prosthesis designs following 36 months of clinical function.

Science.gov (United States)

Rodriguez, A M; Orenstein, I H; Morris, H F; Ochi, S

2000-12-01

The use of endosseous dental implants to replace natural teeth lost to trauma, dental caries, or periodontal disease has become a predictable form of prosthetic treatment since gaining popularity in the early 1980s. While numerous clinical studies have focused on the survival of implants, few address the survival of different prosthesis designs. Beginning in 1991, 882 prostheses supported by more than 2,900 implants (687 patients) were placed by the Department of Veterans Affairs Dental Implant Clinical Research Group (DICRG). These prostheses were divided into five research strata based on arch location. The recommended design for each stratum was: bar-supported overdenture (maxillary completely edentulous); screw-retained hybrid denture (mandibular completely edentulous); screw-retained fixed partial denture (mandibular and maxillary posterior partially edentulous); and cemented single crown (maxillary anterior single tooth). Alternative overdenture designs were utilized in the edentulous arches when the recommended prosthesis could not be fabricated. Prosthesis success rates for the research strata were calculated for an observation time of up to 36 months following prosthesis placement. Success rates for the maxillary edentulous stratum ranged from 94.6% for the bar-retained overdenture supported by five to six fixtures to 81.8% for the cap-retained overdenture. The mandibular edentulous strata produced success rates of 98.1% for the fixed hybrid prosthesis to 91.7% for the cap-retained prosthesis. Success rates for maxillary and mandibular posterior fixed partial dentures were 94.3% and 92.6%, respectively, while the maxillary anterior single-tooth prosthesis yielded a success rate of 98.1% for the 36-month observation period. The recommended prosthesis designs investigated in this study proved to be reliable, with encouraging success rates for an observation period of 36 months following placement.

Microbiota associated with chronic osteomyelitis of the jaws

Directory of Open Access Journals (Sweden)

Elerson Gaetti-Jardim Júnior

2010-12-01

Full Text Available Chronic osteomyelitis of maxilla and mandible is rare in industrialized countries and its occurrence in developing countries is associated with trauma and surgery, and its microbial etiology has not been studied thoroughly. The aim of this investigation was to evaluate the microbiota associated with osteomyelitis of mandible or maxilla from some Brazilian patients. After clinical and radiographic evaluation, samples of bone sequestra, purulent secretion, and biopsies of granulomatous tissues from twenty-two patients with chronic osteomyelitis of mandible and maxilla were cultivated and submitted for pathogen detection by using a PCR method. Each patient harbored a single lesion. Bacterial isolation was performed on fastidious anaerobe agar supplemented with hemin, menadione and horse blood for anaerobes; and on tryptic soy agar supplemented with yeast extract and horse blood for facultative bacteria and aerobes. Plates were incubated in anaerobiosis and aerobiosis, at 37ºC for 14 and 3 days, respectively. Bacteria were cultivated from twelve patient samples; and genera Actinomyces, Fusobacterium, Parvimonas, and Staphylococcus were the most frequent. By PCR, bacterial DNA was detected from sixteen patient samples. The results suggest that cases of chronic osteomyelitis of the jaws are usually mixed anaerobic infections, reinforcing the concept that osteomyelitis of the jaws are mainly related to microorganisms from the oral environment, and periapical and periodontal infections may act as predisposing factors.

Developmental finite element analysis of cichlid pharyngeal jaws: Quantifying the generation of a key innovation

Science.gov (United States)

Müller, Gerd B.

2018-01-01

Advances in imaging and modeling facilitate the calculation of biomechanical forces in biological specimens. These factors play a significant role during ontogenetic development of cichlid pharyngeal jaws, a key innovation responsible for one of the most prolific species diversifications in recent times. MicroCT imaging of radiopaque-stained vertebrate embryos were used to accurately capture the spatial relationships of the pharyngeal jaw apparatus in two cichlid species (Haplochromis elegans and Amatitlania nigrofasciata) for the purpose of creating a time series of developmental stages using finite element models, which can be used to assess the effects of biomechanical forces present in a system at multiple points of its ontogeny. Changes in muscle vector orientations, bite forces, force on the neurocranium where cartilage originates, and stress on upper pharyngeal jaws are analyzed in a comparative context. In addition, microCT scanning revealed the presence of previously unreported cement glands in A. nigrofasciata. The data obtained provide an underrepresented dimension of information on physical forces present in developmental processes and assist in interpreting the role of developmental dynamics in evolution. PMID:29320528

Developmental finite element analysis of cichlid pharyngeal jaws: Quantifying the generation of a key innovation.

Directory of Open Access Journals (Sweden)

Tim Peterson

Full Text Available Advances in imaging and modeling facilitate the calculation of biomechanical forces in biological specimens. These factors play a significant role during ontogenetic development of cichlid pharyngeal jaws, a key innovation responsible for one of the most prolific species diversifications in recent times. MicroCT imaging of radiopaque-stained vertebrate embryos were used to accurately capture the spatial relationships of the pharyngeal jaw apparatus in two cichlid species (Haplochromis elegans and Amatitlania nigrofasciata for the purpose of creating a time series of developmental stages using finite element models, which can be used to assess the effects of biomechanical forces present in a system at multiple points of its ontogeny. Changes in muscle vector orientations, bite forces, force on the neurocranium where cartilage originates, and stress on upper pharyngeal jaws are analyzed in a comparative context. In addition, microCT scanning revealed the presence of previously unreported cement glands in A. nigrofasciata. The data obtained provide an underrepresented dimension of information on physical forces present in developmental processes and assist in interpreting the role of developmental dynamics in evolution.

Need of implant dentistry at undergraduate dental curriculum in Indian dental colleges

Directory of Open Access Journals (Sweden)

Ramesh Chowdhary

2011-01-01

Full Text Available Edentulism is the major problem in the developing countries, and is widely spread in the current population, although the prevalence is declining and incidence of tooth loss is decreasing in the developed nations. The prevalence of edentulism in India varies from 60% to 69% of 25 years and above age group. It is obvious that the number of lost teeth increases with age leading to an increase in prevalence of partially edentulous patients. From a biological point of view, the replacement of a single missing tooth with an implant rather than a three-unit fixed partial denture, and the implant-supported complete denture has been proved more efficient in improving the mastication and maintaining the bone for a longer time and also more cost-effective treatment. Many dental schools throughout Europe and America have to a various extent introduced implant dentistry as part of the compulsory undergraduate curriculum. Thus, it becomes more essential to introduce implant dentistry at undergraduate level in Indian dental schools to manage the higher percentage of edentulism.

Effect of length and location of edentulous area on the accuracy of prosthetic treatment plan incorporation into cone-beam computed tomography scans.

Science.gov (United States)

Jamjoom, Faris Z; Kim, Do-Gyoon; Lee, Damian J; McGlumphy, Edwin A; Yilmaz, Burak

2018-02-05

Effects of length and location of the edentulous area on the accuracy of prosthetic treatment plan incorporation into cone-beam computed tomography (CBCT) scans has not been investigated. To evaluate the effect of length and location of the edentulous area on the accuracy of prosthetic treatment plan incorporation into CBCT scans using different methods. Direct digital scans of a completely dentate master model with removable radiopaque teeth were made using an intraoral scanner, and digital scans of stone duplicates of the master model were made using a laboratory scanner. Specific teeth were removed to simulate different clinical situations and their CBCT scans were made. Surface scans were registered onto the CBCT scans. Radiographic templates for each clinical situation were also fabricated and used during CBCT scans of the master models. Using metrology software, three-dimensional (3D) deviation was measured on standard tesselation language (STL) files created from the CBCT scans against an STL file of the master model created from a CBCT scan. Statistical analysis was done using the MIXED procedure in a statistical software and Tukey HSD test (α =.05). The interaction between location and method was significant (P = .009). Location had no significant effect on registration methods (P > .05), but on the radiographic templates (P = .011). Length of the edentulous area did not have any significant effect (P > .05). Accuracy of digital image registration methods was similar and higher than that of radiographic templates in all clinical situations. Tooth-bound radiographic templates were significantly more accurate than the free-end templates. The results of this study suggest using image registration instead of radiographic templates when planning dental implants, particularly in free-end situations. © 2018 Wiley Periodicals, Inc.

A case of brain abscess caused by radioosteomyelitis of the jaw

International Nuclear Information System (INIS)

Saruwatari, Tomoko; Koga, Makoto; Yoh, Junko; Sakaino, Hidenori; Koga, Chihiro; Kusukawa, Jingo

2008-01-01

We report a rare case of a brain abscess secondary to radioosteomyelitis of the jaw. A 61-year-old man who had received irradiation to a tumor of the tonsil in 1991 had been conservatively treated for radioosteomyelitis of the mandible at our hospital at regular intervals. Then he felt narrowing of the visual field with a serious headache and was immediately admitted to our hospital in September 2006. On the next day, convulsive seizures occurred. Brain CT scanning was immediately performed and demonstrated a low density area in the right occipital lobe. The patient was given a diagnosis of brain abscess. A craniotomy followed by aspiration with drainage was performed by a neurosurgeon. After the operation, the narrowing of visual field improved immediately, and both CT and MRI revealed disappearance of the low density area. Hematogenous infection due to radioosteomyelitis of the jaw was strongly suspected to have caused the brain abscess. After discharge from our hospital, no further symptoms have occurred. (author)

Giant cell lesion of the jaw as a presenting feature of Noonan syndrome.

Science.gov (United States)

Sinnott, Bridget P; Patel, Maya

2018-05-30

This is a case of a 20-year-old woman who presented with a left jaw mass which was resected and found to be a giant cell granuloma of the mandible. Her history and physical examination were suggestive for Noonan syndrome which was confirmed with genetic testing and the finding of a PTPN11 gene mutation which has rarely been associated with giant cell lesions of the jaw. Given her particular genetic mutation and the presence of a giant cell lesion, we present a case of Noonan-like/multiple giant cell lesion syndrome. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Complex Sensory Corpuscles in the Upper Jaw of Horsfield’s Tortoise (Testudo horsfieldii

Directory of Open Access Journals (Sweden)

Marcela Buchtová

2009-01-01

Full Text Available The sensory corpuscles of Testudo horsfieldii in the skin of the upper lip and face were studied with light and electron microscopy. The sensory corpuscles were situated under epidermis; in the corium and also between the upper jaw bone tissues in the rostral part of oral cavity. The skin sensory corpuscles with a ramified inner core were grouped in clusters. Within the corpuscle there were several simple inner cores embedded within a common superficial capsule. The complex corpuscles have a novel structure in comparison to what has been described for sensory nerve endings in turtle. The complex sensory corpuscles probably function as mechanoreceptors important for monitoring the movement of the keratinized ridges and the most rostral part of the upper jaw, the rhamphotheci.

Effects of over-the-counter jaw-repositioning mouth guards on dynamic balance, flexibility, agility, strength, and power in college-aged male athletes.

Science.gov (United States)

Golem, Devon L; Arent, Shawn M

2015-02-01

Improvements in muscular power and anaerobic performance have resulted from the use of jaw-repositioning mouth guards designed with advanced dental techniques. The high cost of such techniques has dissuaded the widespread use. Recently, more affordable, over-the-counter (OTC) jaw-repositioning mouth guards have become available. The primary objective of this study was to examine the effects of 2 OTC jaw-repositioning mouth guards on muscular power and strength performance in college-aged male athletes. It was hypothesized that similar to previous observations with advanced dentistry-designed mouth guards, OTC jaw-repositioning mouth guards would impart positive effects on muscular power but not have any effect on muscular strength. Secondary objectives of this study included the examination of the effects of 2 OTC jaw-repositioning mouth guards on other variables related to athletic performance. Male collegiate athletes (N = 20) participated in 4 separate testing sessions that consisted of assessment of muscular power, dynamic balance, flexibility, agility, and muscular strength. The 4 conditions, 1 per testing session, were assigned in a randomized order and consisted of a no-mouth guard control (CON), a placebo mouth guard, a self-adapted jaw-repositioning mouth guard (SA), and a custom-fitted jaw-repositioning mouth guard (CF). No significant differences were observed between conditions in muscular power (p = 0.78), dynamic balance (p = 0.99), agility (p = 0.22), or muscular strength (p = 0.47). The CF had significantly lower hip flexion than the CON (p = 0.014) and had significantly greater lumbar spine lateral flexion compared with the SA condition (p = 0.054). However, these flexibility differences lack practical relevance as the effect sizes remain very small (ES = -0.27 and -0.14, respectively). In conclusion, the jaw-repositioning technique used in the design of these OTC mouth guards did not affect performance. It is important to note that negative

Effects of Salivary Oxidative Markers on Edentulous Patients' Satisfaction with Prosthetic Denture Treatments: A Pilot Study.

Directory of Open Access Journals (Sweden)

Chia-Huang Chang

Full Text Available The purpose of this study was to assess relationships among periodontal conditions, salivary antioxidant levels, and patients' satisfaction with their prostheses.This study was conducted at the Division of Prosthodontics, Department of Dentistry, Taipei Medical University Hospital. The periodontal condition of patients was based on an assessment of the plaque index (PI and gingival index (GI. The pH value, flow rate, and buffer capacity of the saliva were estimated. The salivary total antioxidant status (TAS and superoxide dismutase (SOD level were also determined. Patients' satisfaction with prosthetic treatments was evaluated using the Chinese version of the short-form Oral Health Impact Profile (OHIP-14C. A multivariate regression model was used to determine whether patients' satisfaction with prosthetic treatment was affected by their oral health status.In total, 35 edentulous patients were recruited. In the Spearman correlation analysis, salivary pH (r = -0.36, p = 0.03 and the buffer ability (r = -0.48, p<0.01 were associated with OHIP-14C scores. In the multivariate analysis, patients who had a higher GI also had a higher score of physical disabilities (β = 1.38, p = 0.04. Levels of SOD increased with the scores of psychological discomfort (β = 0.33 U/g protein, p = 0.04.This study suggested that both the GI and SOD levels were associated with patients' satisfaction with prosthetic treatments. To the best of our knowledge, this is the first study to elucidate the relationship between OHIP scores and salivary oxidative markers in edentulous patients.

The effect of prosthetic rehabilitation and simple dietary counseling on food intake and oral health related quality of life among the edentulous individuals: A randomized controlled trial.

Science.gov (United States)

Amagai, Noriko; Komagamine, Yuriko; Kanazawa, Manabu; Iwaki, Maiko; Jo, Ayami; Suzuki, Hiroyuki; Minakuchi, Shunsuke

2017-10-01

To investigate the combined effect of complete denture renewal and simple dietary advice. A randomized controlled trial was performed with edentulous patients who required new complete dentures. All participants received complete denture treatment. In addition, the intervention group received dietary advice in a pamphlet form, while the control group received advice pertaining to the care and maintenance of the dentures. The advice was given by dentists for each group. The participants' food intake was assessed at baseline and 3 months after intervention using a diet history questionnaire and an oral health related quality of life assessment measured using the Japanese version of the Oral Health Impact Profile for edentulous people (OHIP-EDENT-J). Among 70 participants who were randomized, 62 participants finished all parts of this trial. At baseline, there was no significant difference in the food intake between the two groups. At the 3-month assessment, the intervention group showed significantly greater intake of chicken (P=0.013), fish with bones (P=0.012), and carrots and pumpkins (P=0.025) compared to the control group. However, at baseline and at the 3-month assessment, there was no significant difference in the OHIP-EDENT-J scores between the groups, but the OHIP-EDENT-J scores significantly improved for both groups at the 3-month assessment. There were more significant improved dimensions of OHIP-EDENT-J in the intervention group than in the control group at the 3-month assessment. Simple dietary advice combined with complete denture treatment could improve food intake of edentulous patients. The present study suggests that brief dietary advice provided by dentists can improve food intake of edentulous elderly. This simply diet advice is much easier compared to customized forms, might enable normal dentists provide patients it. The result of this study broadens possibility of nutritional counseling in daily clinical practice. Copyright © 2017 Elsevier Ltd

Incidence of peri-implant mucositis and peri-implantitis in edentulous patients with an implant-retained mandibular overdenture during a 10-year follow-up period

NARCIS (Netherlands)

Meijer, Henny J. A.; Raghoebar, Gerry M.; de Waal, Yvonne C. M.; Vissink, Arjan

2014-01-01

Objectives: The aim of this sub-analysis of two prospective studies was to assess the incidence of peri-implant mucositis and peri-implantitis in fully edentulous patients with an implant-retained mandibular overdenture during a 10-year follow-up period. Material and Methods: One hundred and fifty

Influence of Implant Position on Stress Distribution in Implant-Assisted Distal Extension Removable Partial Dentures: A 3D Finite Element Analysis.

Directory of Open Access Journals (Sweden)

Yeganeh Memari

2014-10-01

Full Text Available Distal extension removable partial denture is a prosthesis with lack of distal dental support with a 13-fold difference in resiliency between the mucosa and the periodontal ligament, resulting in leverage during compression forces. It may be potentially destructive to the abutments and the surrounding tissues. The aim of this study was to assess the effect of implant location on stress distribution, in distal extension implant assisted removable partial dentures.Three-dimensional models of a bilateral distal extension partially edentulous mandible containing anterior teeth and first premolar in both sides of the arch, a partial removable denture and an implant (4×10mm were designed. With the aid of the finite element program ANSYS 8.0, the models were meshed and strictly vertical forces of 10 N were applied to each cusp tip. Displacement and von Mises Maps were plotted for visualization of results.When an implant was placed in the second premolar region, the highest stress on implant, abutment tooth and cancellous bone was shown. The lowest stress was shown on implant and bone in the 1(st molar area.Implants located in the first molar area showed the least distribution of stresses in the analyzed models.

Choice of biomaterials—Do soft occlusal splints influence jaw-muscle activity during sleep? A preliminary report

Science.gov (United States)

Arima, Taro; Takeuchi, Tamiyo; Tomonaga, Akio; Yachida, Wataru; Ohata, Noboru; Svensson, Peter

2012-12-01

AimThe choice of biomaterials for occlusal splints may significantly influence biological outcome. In dentistry, hard acrylic occlusal splints (OS) have been shown to have a temporary and inhibitory effect on jaw-muscle activity, such as tooth clenching and grinding during sleep, i.e., sleep bruxism (SB). Traditionally, this inhibitory effect has been explained by changes in the intraoral condition rather than the specific effects of changes in occlusion. The aim of this preliminary study was to investigate the effect of another type of occlusal surface, such as a soft-material OS in addition to a hard-type OS in terms of changes in jaw-muscle activity during sleep. Materials and methodsSeven healthy subjects (mean ± SD, six men and one woman: 28.9 ± 2.7 year old), participated in this study. A soft-material OS (ethylene vinyl acetate copolymer) was fabricated for each subject and the subjects used the OS for five continuous nights. The EMG activity during sleep was compared to baseline (no OS). Furthermore, the EMG activity during the use of a hard-type OS (Michigan-type OS, acrylic resin), and hard-type OS combined with contingent electrical stimulation (CES) was compared to baseline values. Each session was separated by at least two weeks (washout). Jaw-muscle activity during sleep was recorded with single-channel ambulatory devices (GrindCare, MedoTech, Herlev, Denmark) in all sessions for five nights. ResultsJaw-muscle activity during sleep was 46.6 ± 29.8 EMG events/hour at baseline and significantly decreased during the hard-type OS (17.4 ± 10.5, P = 0.007) and the hard-type OS + CES (10.8 ± 7.1, P = 0.002), but not soft-material OS (36.3 ± 24.5, P = 0.055). Interestingly, the soft-material OS (coefficient of variance = 98.6 ± 35.3%) was associated with greater night-to-night variations than baseline (39.0 ± 11.8%) and the hard-type OS + CES (53.3 ± 13.7%, P < 0.013). ConclusionThe present pilot study in small sample showed that a soft

Florid osseous dysplasia in a middle-aged Turkish woman: A case report

International Nuclear Information System (INIS)

Onder, Buket; Kursun, Sebnem; Oztas, Bengi; Erdem, Erdal

2013-01-01

Florid osseous dysplasia (FOD) is an uncommon, benign, cemento-osseous lesion of the jaws. The etiology of FOD is still unknown. It is often asymptomatic and may be identified on routine dental radiographs. The classic radiographic appearance of FOD is amorphous, lobulated, mixed radiolucent/radiopaque masses of cotton-wool appearance with a sclerotic border in the jaws. In our case the lesion was found incidentally on routine periapical radiographs taken for restored teeth and edentulous areas. For further and detailed examination, a panoramic radiograph and cone-beam computed tomograph (CBCT) were taken. The panoramic radiograph and CBCT revealed maxillary bilateral and symmetrical, non-expansile, well-defined, round, radiopaque masses in contact with the root of the maxillary right second molar and left first molar teeth. Our aim in presenting this case report was to highlight the importance of imaging in diagnosis of FOD.

Florid osseous dysplasia in a middle-aged Turkish woman: A case report

Energy Technology Data Exchange (ETDEWEB)

Onder, Buket; Kursun, Sebnem; Oztas, Bengi [Faculty of Dentistry, Ankara University, Ankara (Turkmenistan); Erdem, Erdal [Dept. of Oral Pathology, Faculty of Dentistry, Gazi University, Ankara (Turkmenistan)

2013-09-15

Florid osseous dysplasia (FOD) is an uncommon, benign, cemento-osseous lesion of the jaws. The etiology of FOD is still unknown. It is often asymptomatic and may be identified on routine dental radiographs. The classic radiographic appearance of FOD is amorphous, lobulated, mixed radiolucent/radiopaque masses of cotton-wool appearance with a sclerotic border in the jaws. In our case the lesion was found incidentally on routine periapical radiographs taken for restored teeth and edentulous areas. For further and detailed examination, a panoramic radiograph and cone-beam computed tomograph (CBCT) were taken. The panoramic radiograph and CBCT revealed maxillary bilateral and symmetrical, non-expansile, well-defined, round, radiopaque masses in contact with the root of the maxillary right second molar and left first molar teeth. Our aim in presenting this case report was to highlight the importance of imaging in diagnosis of FOD.

Brown tumor of the jaw after pregnancy and lactation in a MEN1 patient

Directory of Open Access Journals (Sweden)

Anna Casteràs

2016-11-01

Full Text Available Skeletal manifestations of primary hyperparathyroidism (pHPT include brown tumors (BT, which are osteoclastic focal lesions often localized in the jaws. Brown tumors are a rare manifestation of pHTP in Europe and USA; however, they are frequent in developing countries, probably related to vitamin D deficiency and longer duration and severity of disease. In the majority of cases, the removal of the parathyroid adenoma is enough for the bone to remineralize, but other cases require surgery. Hyperparathyroidism in MEN1 develops early, and is multiglandular and the timing of surgery remains questionable. To our knowledge, there are no reports of BT in MEN 1 patients. We present a 29-year-old woman with MEN 1 who developed a brown tumor of the jaw 24 months after getting pregnant, while breastfeeding. Serum corrected calcium remained under 2.7 during gestation, and at that point reached a maximum of 2.82 mmol/L. Concomitant PTH was 196 pg/mL, vitamin D 13.7 ng/mL and alkaline phosphatase 150 IU/L. Bone mineral density showed osteopenia on spine and femoral neck (both T-scores = −1.6. Total parathyroidectomy was performed within two weeks, with a failed glandular graft autotransplantation, leading to permanent hypoparathyroidism. Two months after removal of parathyroid glands, the jaw tumor did not shrink; thus, finally it was successfully excised. We hypothesize that higher vitamin D and mineral requirements during maternity may have triggered an accelerated bone resorption followed by appearance of the jaw BT. We suggest to treat pHPT before planning a pregnancy in MEN1 women or otherwise supplement with vitamin D, although this approach may precipitate severe hypercalcemia.

Myoelectric manifestations of jaw elevator muscle fatigue and recovery in healthy and TMD subjects.

Science.gov (United States)

Castroflorio, T; Falla, D; Tartaglia, G M; Sforza, C; Deregibus, A

2012-09-01

The effects of muscle pain and fatigue on the control of jaw elevator muscles are not well known. Furthermore, the myoelectric manifestations of fatigue and recovery from fatigue in the masticatory muscles are not reported in literature. The main aims of this study were (i) to evaluate the possible use of surface electromyography (sEMG) as an objective measure of fatigue of the jaw elevator muscles, (ii) to compare the myoelectric manifestations of fatigue in the temporalis anterior and masseter muscles bilaterally, (iii) to assess recovery of the investigated muscles after an endurance test and (iv) to compare fatigue and recovery of the jaw elevator muscles in healthy subjects and patients with muscle-related temporomandibular disorders (TMD). The study was performed on twenty healthy volunteers and eighteen patients with muscle-related TMD. An intra-oral compressive-force sensor was used to measure the voluntary contraction forces close to the intercuspal position and to provide visual feedback of submaximal forces to the subject. Surface EMG signals were recorded with linear electrode arrays during isometric contractions at 20%, 40%, 60% and 80% of the maximum voluntary contraction force, during an endurance test and during the recovery phase. The results showed that (i) the slope of the mean power spectral frequency (MNF) and the initial average rectified value (ARV) could be used to monitor fatigue of the jaw elevators, (ii) the temporalis anterior and masseter muscle show the same myoelectric manifestations of fatigue and recovery and (iii) the initial values of MNF and ARV were lower in patients with muscle-related TMD. The assessment of myoelectric manifestations of fatigue in the masticatory muscles may assist in the clinical assessment of TMDs. © 2012 Blackwell Publishing Ltd.

Finite Element Analysis of the Cingulata Jaw: An Ecomorphological Approach to Armadillo's Diets.

Directory of Open Access Journals (Sweden)

Sílvia Serrano-Fochs

Full Text Available Finite element analyses (FEA were applied to assess the lower jaw biomechanics of cingulate xenarthrans: 14 species of armadillos as well as one Pleistocene pampathere (11 extant taxa and the extinct forms Vassallia, Eutatus and Macroeuphractus. The principal goal of this work is to comparatively assess the biomechanical capabilities of the mandible based on FEA and to relate the obtained stress patterns with diet preferences and variability, in extant and extinct species through an ecomorphology approach. The results of FEA showed that omnivorous species have stronger mandibles than insectivorous species. Moreover, this latter group of species showed high variability, including some similar biomechanical features of the insectivorous Tolypeutes matacus and Chlamyphorus truncatus to those of omnivorous species, in agreement with reported diets that include items other than insects. It remains unclear the reasons behind the stronger than expected lower jaw of Dasypus kappleri. On the other hand, the very strong mandible of the fossil taxon Vassallia maxima agrees well with the proposed herbivorous diet. Moreover, Eutatus seguini yielded a stress pattern similar to Vassalia in the posterior part of the lower jaw, but resembling that of the stoutly built Macroeuphractus outesi in the anterior part. The results highlight the need for more detailed studies on the natural history of extant armadillos. FEA proved a powerful tool for biomechanical studies in a comparative framework.

Small vertical changes in jaw relation affect motor unit recruitment in the masseter.

Science.gov (United States)

Terebesi, S; Giannakopoulos, N N; Brüstle, F; Hellmann, D; Türp, J C; Schindler, H J

2016-04-01

Strategies for recruitment of masseter muscle motor units (MUs), provoked by constant bite force, for different vertical jaw relations have not previously been investigated. The objective of this study was to analyse the effect of small changes in vertical jaw relation on MU recruitment behaviour in different regions of the masseter during feedback-controlled submaximum biting tasks. Twenty healthy subjects (mean age: 24·6 ± 2·4 years) were involved in the investigation. Intra-muscular electromyographic (EMG) activity of the right masseter was recorded in different regions of the muscle. MUs were identified by the use of decomposition software, and root-mean-square (RMS) values were calculated for each experimental condition. Six hundred and eleven decomposed MUs with significantly (P recruitment behaviour were organised into localised MU task groups. MUs with different task specificity in seven examined tasks were observed. The RMS EMG values obtained from the different recording sites were also significantly (P recruitment was significantly (P recruited MUs and the RMS EMG values decreased significantly (P recruitment behaviour in discrete subvolumes of the masseter in response to small changes in vertical jaw relations. These fine-motor skills might be responsible for its excellent functional adaptability and might also explain the successful management of temporomandibular disorder patients by somatic intervention, in particular by the use of oral splints. © 2015 John Wiley & Sons Ltd.

Extracting DNA from 'jaws': High yield and quality from archived tiger shark (Galeocerdo cuvier) skeletal material

DEFF Research Database (Denmark)

Eg Nielsen, Einar; Morgan, J. A T; Maher, S. L.

2017-01-01

of tiger sharks (Galeocerdo cuvier). Protocols were compared for DNA yield and quality using a qPCR approach. For jaw swarf, all methods provided relatively high DNA yield and quality, while large differences in yield between protocols were observed for vertebrae. Similar results were obtained from samples...... observed, likely reflecting different preparation and storage methods for the trophies. Trial sequencing of DNA capture genomic libraries using 20 000 baits revealed that a significant proportion of captured sequences were derived from tiger sharks. This study demonstrates that archived shark jaws...

[Clinical experience in osteoplastic material Allomatrix-implant and fibrin rich platelets use in surgical treatment of jaw radicular cysts].

Science.gov (United States)

Kuz'minykh, I A

2009-01-01

Bones forming optimizators applying in surgical dentistry is an important element of jaw destructive processes successful treatment. Today use of osteoplastic materials on the collagen basis is widely spread. One of this challenge solution is FRP and Allomatrix-implant material applying to jaws during surgery operations. We described clinical investigation phase: the estimation of postoperative and remote results of treatment was carried out.

Central giant cell granuloma of the jaws: clinical and radiological evaluation of 22 cases

International Nuclear Information System (INIS)

Sun, Zhi-Jun; Cai, Yu; Zhao, Yi-Fang; Zwahlen, Roger A.; Zheng, Yun-Fei; Wang, Shi-Ping

2009-01-01

The objective was to investigate the clinical and radiological characteristics of central giant cell granulomas (CGCGs) of the jaws. A retrospective analysis of a 20-year database was performed regarding both clinical and radiological features of 22 patients affected with CGCGs of the jaws. Fourteen women and 8 men were included with the age range of 7-81 years (mean 31.7 years). Among the 22 lesions, 16 were located in the mandible and 6 in the maxilla. Painless swelling was the most common clinical feature in 18 of all cases. Limited mouth opening was noted in 2 patients where the lesions involved the condyle. Radiographically, 13 lesions were homogeneously osteolytic and 9 lesions were trabeculated. Fifteen lesions were unilocular and 14 lesions presented with well-defined but not sclerotic margins. CT images in 5 patients clearly showed the trabeculation within the lesions. The follow-up ranged from 1.5 to 11 years with a mean period of 5 years. Three out of 9 aggressive and 1 out of 13 nonaggressive lesions developed recurrence. Diagnosis of CGCGs of the jaws depends on both correct interpretation of clinical, radiographic and pathological data. Differentiation between aggressive and nonaggressive CGCGs should be considered to improve individual treatment planning. (orig.)

Central giant cell granuloma of the jaws: clinical and radiological evaluation of 22 cases

Energy Technology Data Exchange (ETDEWEB)

Sun, Zhi-Jun; Cai, Yu; Zhao, Yi-Fang [School and Hospital of Stomatology, Wuhan University, Key Laboratory for Oral Biomedical Engineering of Ministry of Education, Wuhan, Hubei (China); Wuhan University, Department of Oral and Maxillofacial Surgery, School and Hospital of Stomatology, Wuhan, Hubei (China); Zwahlen, Roger A. [University of Hong Kong, Discipline of Oral and Maxillofacial Surgery, Faculty of Dentistry (China); Zheng, Yun-Fei [School and Hospital of Stomatology, Wuhan University, Key Laboratory for Oral Biomedical Engineering of Ministry of Education, Wuhan, Hubei (China); Wang, Shi-Ping [Wuhan University, Department of Oral and Maxillofacial Radiology, School and Hospital of Stomatology, Wuhan (China)

2009-09-15

The objective was to investigate the clinical and radiological characteristics of central giant cell granulomas (CGCGs) of the jaws. A retrospective analysis of a 20-year database was performed regarding both clinical and radiological features of 22 patients affected with CGCGs of the jaws. Fourteen women and 8 men were included with the age range of 7-81 years (mean 31.7 years). Among the 22 lesions, 16 were located in the mandible and 6 in the maxilla. Painless swelling was the most common clinical feature in 18 of all cases. Limited mouth opening was noted in 2 patients where the lesions involved the condyle. Radiographically, 13 lesions were homogeneously osteolytic and 9 lesions were trabeculated. Fifteen lesions were unilocular and 14 lesions presented with well-defined but not sclerotic margins. CT images in 5 patients clearly showed the trabeculation within the lesions. The follow-up ranged from 1.5 to 11 years with a mean period of 5 years. Three out of 9 aggressive and 1 out of 13 nonaggressive lesions developed recurrence. Diagnosis of CGCGs of the jaws depends on both correct interpretation of clinical, radiographic and pathological data. Differentiation between aggressive and nonaggressive CGCGs should be considered to improve individual treatment planning. (orig.)

Imaging of the jaw cysts with a dental CT software program : distinction of odontogenic keratocysts from other cysts

International Nuclear Information System (INIS)

Lee, Jung Man; Shin, Sang Hoon; Lee, Won Hoon; Oh, Kyu Hyen; Jung, Hak Young; Lee, Young Hwan; Sung, Nak Kwan; Jung, Duck Soo; Kim, Ok Dong

1997-01-01

To evaluate the usefulness of a dental CT software program in the assessment of jaw cysts and in the differentiation of odontogenic keratocysts and other cysts. Seventeen patients with proven jaw cysts(8 maxillae and 9 mandibles) were evaluated with a dental CT sofware program for location, locularity, the presence or absence of marginal scallping, and height to length ratio. For the delineation of involvement or displace-ment of neurovascular bundles, cortical erosion, perforation or expansion, and tooth root resorption by the jaw cysts, images from this program were compared to conventional images. Seventeen lesions icomprised 15 odontogenic cysts (five odontogenic keratocysts, five radicular, three residual and two dentigerous cysts) and two non-odontogenic cysts (one nasopalatine duct cyst and one postoperative maxillary cyst). Images of jaw cysts obtained with the dental CT software program delineated much more clearly than conventional images the status of neurovascular bundle and cortical bone, but there was no clear difference between the two modalities in delineating tooth root erosion. Dental CT findings of five mandibular odontogenic keratocysts were scalloped margin in all, mandibular ramus involvement in four, height to length ratio below 60% in four ,and multilocularity in two. The findings of the other 12 cysts (eight maxillae and four mandibles) were unilocularity in all, smooth inner margin in ten, height to length ratio below 60% in only two, and ramus involvement in none. A dental CT software program is an improved imaging modality for assessing jaw cysts;and findings which tend to indicate odontogenic keratocysts are marginal scalloping, mandibular ramus involvement, prominent spread along the marrow space and multilocularity

High-resolution computed tomography of the toothed jaw compared with histologic microsections

International Nuclear Information System (INIS)

Klein, H.M.; Fuhrmann, R.; Diedrich, P.; Guenther, R.W.

1993-01-01

Human bone segments of the toothed jaw were scanned using high-resolution CT with axial and coronal contiguous 1 and 2 mm slices. The bone segments were sliced analogous to the performed CT image positions. Contact films and micro-sections were made from the cuttings. Length and width of the teeth, the thickness of the alveolar bone and the distance between bone and dental surface were measured. Comparison of the CT measurements with contact films and histological specimen yielded best results for axial slices with 1 mm slice thickness (mean error 0.3-0.5 mm). Coronary oriented slices showed an error of 0.3-1.6 mm. 3D-reformatting can improve spatial orientation for axially produced image series. For CT imaging of the toothed jaw concerning the dento-alveolar structures, contiguous axial scanning with 1 mm slice thickness appears to be the concept of choice. (orig.) [de

A novel method for single sample multi-axial nanoindentation of hydrated heterogeneous tissues based on testing great white shark jaws.

Science.gov (United States)

Ferrara, Toni L; Boughton, Philip; Slavich, Eve; Wroe, Stephen

2013-01-01

Nanomechanical testing methods that are suitable for a range of hydrated tissues are crucial for understanding biological systems. Nanoindentation of tissues can provide valuable insights into biology, tissue engineering and biomimetic design. However, testing hydrated biological samples still remains a significant challenge. Shark jaw cartilage is an ideal substrate for developing a method to test hydrated tissues because it is a unique heterogeneous composite of both mineralized (hard) and non-mineralized (soft) layers and possesses a jaw geometry that is challenging to test mechanically. The aim of this study is to develop a novel method for obtaining multidirectional nanomechanical properties for both layers of jaw cartilage from a single sample, taken from the great white shark (Carcharodon carcharias). A method for obtaining multidirectional data from a single sample is necessary for examining tissue mechanics in this shark because it is a protected species and hence samples may be difficult to obtain. Results show that this method maintains hydration of samples that would otherwise rapidly dehydrate. Our study is the first analysis of nanomechanical properties of great white shark jaw cartilage. Variation in nanomechanical properties were detected in different orthogonal directions for both layers of jaw cartilage in this species. The data further suggest that the mineralized layer of shark jaw cartilage is less stiff than previously posited. Our method allows multidirectional nanomechanical properties to be obtained from a single, small, hydrated heterogeneous sample. Our technique is therefore suitable for use when specimens are rare, valuable or limited in quantity, such as samples obtained from endangered species or pathological tissues. We also outline a method for tip-to-optic calibration that facilitates nanoindentation of soft biological tissues. Our technique may help address the critical need for a nanomechanical testing method that is applicable

A novel method for single sample multi-axial nanoindentation of hydrated heterogeneous tissues based on testing great white shark jaws.

Directory of Open Access Journals (Sweden)

Toni L Ferrara

Full Text Available Nanomechanical testing methods that are suitable for a range of hydrated tissues are crucial for understanding biological systems. Nanoindentation of tissues can provide valuable insights into biology, tissue engineering and biomimetic design. However, testing hydrated biological samples still remains a significant challenge. Shark jaw cartilage is an ideal substrate for developing a method to test hydrated tissues because it is a unique heterogeneous composite of both mineralized (hard and non-mineralized (soft layers and possesses a jaw geometry that is challenging to test mechanically. The aim of this study is to develop a novel method for obtaining multidirectional nanomechanical properties for both layers of jaw cartilage from a single sample, taken from the great white shark (Carcharodon carcharias. A method for obtaining multidirectional data from a single sample is necessary for examining tissue mechanics in this shark because it is a protected species and hence samples may be difficult to obtain. Results show that this method maintains hydration of samples that would otherwise rapidly dehydrate. Our study is the first analysis of nanomechanical properties of great white shark jaw cartilage. Variation in nanomechanical properties were detected in different orthogonal directions for both layers of jaw cartilage in this species. The data further suggest that the mineralized layer of shark jaw cartilage is less stiff than previously posited. Our method allows multidirectional nanomechanical properties to be obtained from a single, small, hydrated heterogeneous sample. Our technique is therefore suitable for use when specimens are rare, valuable or limited in quantity, such as samples obtained from endangered species or pathological tissues. We also outline a method for tip-to-optic calibration that facilitates nanoindentation of soft biological tissues. Our technique may help address the critical need for a nanomechanical testing method

Patient satisfaction with laser-sintered removable partial dentures: A crossover pilot clinical trial.

Science.gov (United States)

Almufleh, Balqees; Emami, Elham; Alageel, Omar; de Melo, Fabiana; Seng, Francois; Caron, Eric; Nader, Samer Abi; Al-Hashedi, Ashwaq; Albuquerque, Rubens; Feine, Jocelyne; Tamimi, Faleh

2018-04-01

Clinical data regarding newly introduced laser-sintered removable partial dentures (RPDs) are needed before this technique can be recommended. Currently, only a few clinical reports have been published, with no clinical studies. This clinical trial compared short-term satisfaction in patients wearing RPDs fabricated with conventional or computer-aided design and computer-aided manufacturing (CAD-CAM) laser-sintering technology. Twelve participants with partial edentulism were enrolled in this pilot crossover double-blinded clinical trial. Participants were randomly assigned to wear cast or CAD-CAM laser-sintered RPDs for alternate periods of 30 days. The outcome of interest was patient satisfaction as measured using the McGill Denture Satisfaction Instrument. Assessments was conducted at 1, 2, and 4 weeks. The participant's preference in regard to the type of prosthesis was assessed at the final evaluation. The linear mixed effects regression models for repeated measures were used to analyze the data, using the intention-to-treat principle. To assess the robustness of potential, incomplete adherence, sensitivity analyses were conducted. Statistically significant differences were found in patients' satisfaction between the 2 methods of RPD fabrication. Participants were significantly more satisfied with laser-sintered prostheses than cast prostheses in regard to general satisfaction, ability to speak, ability to clean, comfort, ability to masticate, masticatory efficiency, and oral condition (Premovable partial dentures may lead to better outcomes in terms of patient satisfaction in the short term. The conclusion from this pilot study requires confirmation by a larger randomized controlled trial. ClinicalTrials.gov. A study about patient satisfaction with laser-sintered removable partial dentures; NCT02769715. Copyright © 2017 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

Renal osteodystrophy with facial hyperostosis and 'rubber jaw' in an adult dog.

Science.gov (United States)

Kyle, M G; Davis, G B; Thompson, K G

1985-07-01

A nine-year-old male Sheltie dog was presented with bilaterally symmetrical maxilliary swelling, loose teeth and flexible mandibles. The condition was progressive over a period of two months. Biochemical and histopathological examinations supported a diagnosis of renal osteodystrophy with facial hyperostosis and 'rubber jaw'.

Correlation between bone mineral density of jaws and skeletal sites in an Iranian population using dual X-ray energy absorptiometry.

Science.gov (United States)

Esfahanizadeh, Nasrin; Davaie, Sotoudeh; Rokn, A R; Daneshparvar, Hamid Reza; Bayat, Noushin; Khondi, Nasrin; Ajvadi, Sara; Ghandi, Mostafa

2013-07-01

The aim of the present study was to evaluate the relationship between the bone density of various regions of jaws and skeletal bones. A total of 110 patients with a mean age of 55.01 ± 10.77 years were selected for the purpose of the present descriptive study. Dual X-ray Energy Absorptiometry (DXA) was carried out to determine bone mineral density (BMD) of the femur and lumbar vertebrae. Then all the subjects underwent DXA of the jaw bones and BMD values were determined at four jaw regions. Data were analyzed by SPSS 16 statistical software, and the correlation between the various BMD values was determined by Pearson's correlation coefficient. The results showed that 42.7% of females had normal BMD values in the femur, and in vertebrae, 20% were osteopenic and 37.3% suffered from osteoporosis, with statistically significant differences in the BMD values of the jaws between the three above-mentioned groups (P < 0.001). There was an increasing tendency toward osteopenia and osteoporosis with age. There was a positive correlation between BMD values of the femur and lumbar vertebrae and those of all the jaw regions under study (P < 0.005). There was a negative correlation (P < 0.01) between age and the BMD values of the femur, lumbar vertebrae and anterior maxilla. The bone density of the maxilla and mandible and presence of osteoporosis or osteopenia in these bones might reflect the same problem in skeletal bones.

Morphology of the jaw, suspensorial, and opercle musculature of Beloniformes and related species (Teleostei: Acanthopterygii), with a special reference to the m. adductor mandibulae complex.

Science.gov (United States)

Werneburg, Ingmar

2015-01-01

The taxon Beloniformes represents a heterogeneous group of teleost fishes that show an extraordinary diversity of jaw morphology. I present new anatomical descriptions of the jaw musculature in six selected beloniforms and four closely related species. A reduction of the external jaw adductor (A1) and a changed morphology of the intramandibular musculature were found in many Beloniformes. This might be correlated with the progressively reduced mobility of the upper and lower jaw bones. The needlefishes and sauries, which are characterised by extremely elongated and stiffened jaws, show several derived characters, which in combination enable the capture of fish at high velocity. The ricefishes are characterised by several derived and many plesiomorphic characters that make broad scale comparisons difficult. Soft tissue characters are highly diverse among hemiramphids and flying fishes reflecting the uncertainty about their phylogenetic position and interrelationship. The morphological findings presented herein may help to interpret future phylogenetic analyses using cranial musculature in Beloniformes.

Morphology of the jaw, suspensorial, and opercle musculature of Beloniformes and related species (Teleostei: Acanthopterygii, with a special reference to the m. adductor mandibulae complex

Directory of Open Access Journals (Sweden)

Ingmar Werneburg

2015-02-01

Full Text Available The taxon Beloniformes represents a heterogeneous group of teleost fishes that show an extraordinary diversity of jaw morphology. I present new anatomical descriptions of the jaw musculature in six selected beloniforms and four closely related species. A reduction of the external jaw adductor (A1 and a changed morphology of the intramandibular musculature were found in many Beloniformes. This might be correlated with the progressively reduced mobility of the upper and lower jaw bones. The needlefishes and sauries, which are characterised by extremely elongated and stiffened jaws, show several derived characters, which in combination enable the capture of fish at high velocity. The ricefishes are characterised by several derived and many plesiomorphic characters that make broad scale comparisons difficult. Soft tissue characters are highly diverse among hemiramphids and flying fishes reflecting the uncertainty about their phylogenetic position and interrelationship. The morphological findings presented herein may help to interpret future phylogenetic analyses using cranial musculature in Beloniformes.

The relevance of clinical and radiographic features of jaw lesions: A prospective study

Directory of Open Access Journals (Sweden)

Juliane Piragine ARAUJO

Full Text Available Abstract The study was carried out in a Brazilian population and the aim was to describe the prevalence and the clinic-radiographical features of jaw lesions. In addition, a comparison between the main diagnosis hypothesis and final diagnosis was accessed. A prospective study which evaluated all patients with jaw lesions diagnosed in an Oral Diagnosis Center, between August 2013 and October 2014. A total of 450 patients were observed for the first time, and 130 had some type of jaw lesion. The mean age of the patients was 35.2 years ± 17.86. Among these, 71 were women (54.62% and 87 were Caucasian (66.92%. The mandible was affected more frequently (71.43% than the maxilla (28.57%. Swelling and pain were the most frequent clinical signs and symptoms and were observed in 60 (42.85% and 38 (27.14% cases, respectively. The panoramic x-ray was the main radiographic exam utilized (88.57%. Radiolucent lesions accounted for 89 cases (63.57% and the unilocular form was present in 114 cases (81.43%. A total of 93 cases had histopathological analyses and the periapical cyst was the most frequent lesion. In the other 47 lesions, the diagnosis was conducted by clinical and radiographic management. Bone lesions were frequent, being noted on first visit in approximately 30% of patients; in 1/3 of the cases, the diagnoses were completed with a combination of clinical and radiographic exams.

Relationships among nocturnal jaw muscle activities, decreased esophageal pH, and sleep positions.

Science.gov (United States)

Miyawaki, Shouichi; Tanimoto, Yuko; Araki, Yoshiko; Katayama, Akira; Imai, Mikako; Takano-Yamamoto, Teruko

2004-11-01

The purpose of this study was to examine the relationships among nocturnal jaw muscle activities, decreased esophageal pH, and sleep positions. Twelve adult volunteers, including 4 bruxism patients, participated in this study. Portable pH monitoring, electromyography of the temporal muscle, and audio-video recordings were conducted during the night in the subjects' homes. Rhythmic masticatory muscle activity (RMMA) episodes were observed most frequently, with single short-burst episodes the second most frequent. The frequencies of RMMA, single short-burst, and clenching episodes were significantly higher during decreased esophageal pH episodes than those during other times. Both the electromyography and the decreased esophageal pH episodes were most frequently observed in the supine position. These results suggest that most jaw muscle activities, ie, RMMA, single short-burst, and clenching episodes, occur in relation to gastroesophageal reflux mainly in the supine position.

A Simple Method for Prosthodontic Rehabilitation of Edentulous Patient with Epidermolysis Bullosa: A Clinical Case Report

Directory of Open Access Journals (Sweden)

Farhang Mahboub

2011-06-01

Full Text Available An abnormally small oral orifice is defined as microstomia. Microstomia may result from epidermolysis bullosa (EB, which consists of a group of disorders characterized by the presence of mechanical fragility of the skin with recurrent development of blisters and vesicles, resulting from minor mechanical friction or trauma. Since such patients have a small oral aperture, it may be impossible to take impression and fabricate dentures using conventional methods. In this article, a simple method for taking preliminary impressions from upper and lower edentulous ridges in one patient with limited mouth opening and then preparing the complete denture with custom denture teeth in a single unit was described.

Myxoma of the Jaw Bones: Analysis of 27 Cases | Ajike | Nigerian ...

African Journals Online (AJOL)

Twenty-seven patients with histologically confirmed cases of odontogenic myxoma of the jaws were managed in a 10-year period. They represent 8.5% of all odontogenic tumours seen during the period. There was a female preponderance with the female to male ratio of 2.4:1. The age range was 11-70 years with majority ...

Implant planning on NobelClinician software‎ : incidence of bone density on the implants orientation for completely edentulous maxillae