Bar Attachment Research Articles

The effects of bone remodeling on biomechanical behavior in a patient with an implant-supported overdenture

This study aimed to clarify the effects of bone remodeling on biomechanical behavior in a patient with a mandibular implant-supported overdenture by comparing computed tomography-based finite element analyses (CT-FEA) with two time points of CT data. The present FEA was based on CT data collected from a 62-year-old female subject, who wore a mandibular implant overdenture supported by four dental implants with bar attachment. Two kinds of FE models were constructed from CT data taken at two time points: pre-implantation (Original-model) and 12 years post-implantation (Aged-model). FE models consisted of patient-specific model geometry and heterogeneous material properties. The deviation analysis was carried out to assess the changes in bone mass over a period of 12 years. The results show an averaging of intraosseous stress and strain energy density between the implant regions in the Aged-model. The results of the morphological assessments demonstrated that the bone mass and quality had significantly changed over 12 years. Area-specific bone resorption was also observed at the bone surrounding each implant. The combined findings indicate that the averaging of mechanical variables was due to chronological changes in bone morphology, suggesting adaptation to mechanical loads by peri-implant bone remodeling.

Comparison in Bone Density Changes for Two Different Designs in Treatment of Mandibular Bilateral Free End Saddle with Osseointegrated Implants

AIM: The aim of this study is to evaluate two different designs in mandibular bilateral free end saddle cases with the use of osseointegrated implants. The designs evaluated were OT-strategy extracoronal attachment and bar attachment. Radiographic evaluation was carried out for implants and natural abutment in terms of bone density.
 MATERIALS AND METHODS: This study was conducted on 10 patients with bilateral distal extension area with missing molars bilaterally; the patients were divided into two groups after implant insertion on the second molar area. Group I: Patients received extracoronal attachment distal to the last natural abutment teeth with the construction of metallic removable partial denture (RPD). Group II: Patients received bar attachment with the construction of metallic RPD. Both groups have the maxillary arch edentulous with the construction of complete maxillary dentures within our study. Radiographic evaluation for bone density was done for both groups at the time of prosthesis insertion, 3, 6, and 9 months later. A comparison between the two groups regarding each follow-up period was performed by an independent t-test.
 RESULTS: Although there were some differences between both designs in the 1st-time intervals, generally, there were no significant differences between the two designs all over the 3-time intervals.
 CONCLUSION: From the results of this study, it was concluded that: Although there were no significant differences between both designs, bar-attachment showed better results which should be confirmed with more future researches.

Clinical outcomes of implant-retained mandibular overdentures using the bar and magnetic attachment systems: an up to 5-year retrospective study.

BackgroundImplant-retained mandibular overdentures (IODs) represent an effective and reliable treatment modality for edentulous patients. The present retrospective study compared the clinical outcomes of IODs using bar attachment (BA) system with those using magnetic attachment (MA) system after functioning for up to 5 years.MethodsHuman subjects treated with IODs between 01-01-2010 and 12-31-2014 were identified from patient records. Of the 54 subjects who met the inclusion criteria, 48 subjects including 26 treated with BA-IODs and 22 with MA-IODs (96 mandibular implants) were recruited for the study. The implant units and prostheses were evaluated individually for peri-implant health. Prosthetic complications and maintenance during follow-up were recorded. The subjects responded to the visual analog scale (VAS) and the Oral Health Impact Profile questionnaires for evaluation of patient satisfaction and oral health-related quality of life (OHRQoL).ResultsThe survival rates of the implants and prostheses were 96.9% and 95.8%, respectively, over a mean observation period of 48±11.3 (range, 13–64) months. Peri-implant probing depth (PPD) and plaque index (PI) were significantly better for the MA group compared with the BA group (P<0.05), while marginal bone loss (MBL) and sulcus bleeding index (SBI) showed no significant differences (P>0.05). Prosthetic complications and maintenance were attachment-dependent. Most recruited subjects were satisfied with their prostheses. There was no statistically significant difference regarding general patient satisfaction or OHRQoL between the two groups (P>0.05). Nevertheless, patients complained that the BA-IODs were significantly more difficult to clean than the MA-IODs (P<0.05).ConclusionsIODs have an ideal medium-term outcome irrespective of the attachment design. It is recommended that oral hygiene instructions and regular clinical examination be given to subjects wearing IODs.

Two Years after Loading Performance of Implant-Supported Overdenture with Metal Bar and Low-Profile Attachments: A Prospective Case Series Multicenter Clinical Study

Background. Prosthetic rehabilitation of patients with atrophic arches can be very challenging. Purpose. The aim of the present prospective multicenter study was to report the two-year preliminary data on clinical and radiographic performance of implant-supported overdentures with a metal bar and low-profile attachments. Material and Methods. A computer-aided design/computer-aided manufacturing (CAD/CAM) titanium bar or a conventional cast metal bar was fabricated according to the anatomy of the ridge, prosthetic contours (teeth setup), and implant position. Three to six threadable OT Equator attachments (Rhein 83, Bologna, Italy) were placed along the implant bar. A cobalt-chromium alloy metal framework was fabricated and fitted onto the metal bar as a counterpart. Prosthetic survival rate, biologic and technical complications, peri-implant bone loss, changes in oral health impact profile index, bleeding on probing, and plaque index were reported. Results. Overall, 177 implants were placed (range three to six) to support 43 metal bars with 170 OT Equators (Rhein 83, range three to six). Eleven metal bars were fabricated using CAD/CAM technology, while the other 32 were conventionally produced using cast technique. All the participants were followed up for at least two years (mean 42.2 months, range 24–88 months) after prosthesis delivery. Two maxillary implants failed in one nonsmoking patient (1.1%). The 2-year prosthesis survival rate was 97.7%. Only three minor technical complications were reported. Two years after loading, the mean marginal bone loss was 0.22 ± 0.09 mm (95% CI: 0.16 to 0.26). Two years after loading, OHIP was 22.3 ± 7.1 (95% CI from 17.4 to 24.6). Compared to the baseline, the difference was statistically significant ( P ≤ 0.001 ). At the two-year follow-up session, successful periodontal parameters were experienced. Conclusions. Implant overdenture supported by a CAD/CAM titanium bar may be a reliable option for the treatment of the edentulous arch over a 2-year period. Oral health-related quality of life significantly improved in all treated participants.

Restoration of Microtia by Prosthetic Method: A Case Report

Background: Microtia is one of the forms of ear loss and deformity. It is a congenital anomaly of the external ear. Social and psychological rehabilitation of such patients requires a prosthesis that is esthetic as well as has enough strength and texture to represent the natural ear. Because of financial constraints, some patients cannot afford the surgical procedure of grafting.&#x0D; Case report: This is a case of 17 year old female with congenital missing right ear along with facial deformity due to Lower Motor Neuron facial nerve palsy. &#x0D; Treatment plan: Prosthetic replacement of the missing ear was planned to improve the esthetic and social well being of the patient in an economical way.&#x0D; Conclusion: a definitive management of the missing ear can be done using dental implants and bar attachment if the financial condition and social acceptance with interim prosthesis is satisfactory.

Contemporary treatment modalities for definitive rehabilitation of acquired maxillary defects – A review

Various techniques have been described to restore acquired maxillary defects. The aim of this paper is to review the contemporary treatment modalities that have been explored to rehabilitate and reconstruct partial or complete maxillectomy in dentulous and edentulous patients. MEDLINE/PUBMED search was conducted for dental literature published from January 2000 to December 2018. Literature study revealed various methods and materials used to treat patients with acquired maxillary defects. These include modifications in method and materials used for the fabrication of conventional obturators (using precision and semi-precision attachments, telescopic copings, magnets, silicone based materials, titanium and its alloys, PEEK, thermoplastic resin); implant-supported obturators supported on conventional, zygomatic and pterygoid implants using different attachments (ERA, magnet, bar attachment, locator, ball attachment); use of CAD/CAM technology for presurgical planning and fabrication of obturator prosthesis; surgical reconstruction with microvascular free tissue flaps; and bone engineering. Significant attention has been devoted to refining current methods and developing better methods to successfully rehabilitate maxillectomy patients. The use of osseointegrated implants, newer prosthesis materials, advanced laboratory procedures, inclusion of CAD/CAM technology, advances in surgical reconstructive techniques and tissue engineering has revolutionized the traditional treatment options. Keywords: Maxillectomy, Implants in maxillectomy, Microvascular free flap, Bone tissue engineering.

Andrew’s bridge: A prosthetic option for missing anterior teeth with severe ridge defect

Prosthodontic rehabilitation of mandibular anterior missing teeth with large ridge defect due to poor abutment support and inadequate quality and quantity of bone. Often, a customised treatment plan has to be drawn to meet patient’s requirement of estheics, form, function and longevity of the prosthesis. This article describes procedure for fabrication of fixed-removable type of prosthesis in such cases. Keywords: Andrew’s bridge, Ridge defect, Mandibular anterior, Horix bar attachment.

Nano-hybrid versus micro-hybrid composite as reinforced resin for ribbon bar attachment.

Nano-hybrid versus micro-hybrid composite as reinforced resin for ribbon bar attachment.

Satisfaction of Patient with Stud, Bar and Magnet Attachment Systems for Mandibular Two-Implant Over Dentures

Satisfaction of Patient with Stud, Bar and Magnet Attachment Systems for Mandibular Two-Implant Over Dentures

Minimally Invasive Treatment of Edentulous Maxillae with Overdenture Fully Supported by a Cad/Cam Titanium Bar with a Low-Profile Attachment Screwed on Four or Six Implants: A Case Series

Rehabilitation of atrophic maxilla still remains a challenge. Fixed implant-supported restorations have become more predictable in the last years; nevertheless, technical and biological complications still occur. Removable overdenture fully supported by a CAD/CAM titanium bar seems to be a viable treatment option for the rehabilitation of completely edentulous patients with a high degree of bone resorption. In these clinical cases, the soft tissues of the lower third of the face need to be respected, and a fixed-removable solution is the only option to have good hygiene control. Nevertheless, there is no consensus about the optimal number and position of the implants. A total of six adult patients were recruited and treated with an overdenture fully supported by a CAD/CAM titanium bar and low-profile attachment, screwed on four or six implants. A detailed step-by-step description of the procedures was presented. Overall, all the patients were successful treated with no relevant complications. With the limitations of this case series, maxillary implant overdenture fully supported by four or six implants seems to be a safer treatment option for the minimally invasive rehabilitation of atrophic maxillae, regardless of the number of implants.

DÖRT FARKLI TIP ALVEOLER DEFEKTE SAHIP MAKSILLADA DÖRTLÜ ZIGOMATIK İMPLANT UYGULAMASININ BIYOMEKANIK ETKILERININ DEĞERLENDIRILMESI

Bulgular: Beş model arasında, kemikte görülen en yüksek Von Mises Stres değeri, tek taraflı kusurlu (1/3 kusurlu) maksillada bulundu. Deformasyon değeri 2/3 kusurlu maksilla modelinde en yüksek bulundu. Asimetrik defekt modellerinde, maksilla'nın sağlam kısmında daha yüksek stres değerleri elde edildi. Simetrik kusurlu modellerde, stresin daha homojen bir şekilde dağıldığı görüldü. Anahtar Kelimeler: Zigomatik implant, kuad zigoma, maksillar defekt, sonlu elemanlar analizi Evaluation of Biomechanical Effects of Quad Zigomatic Implant Applications in Four Different Maxillary Defect Types Abstract Purpose: The purpose of this study is to evaluate the biomechanical effects of quad zygomatic implant use in four different type alveolar defected maxilla. Materials and Methods: Three dimensional models of human skull, zygomatic implants, bar attachment and hybrid prosthesis was modeled using SolidWorks Computer-Aided Design (CAD) program. Four different defect locations were modeled on intact model to mimic different alveolar defect scenarios. In all models, four zygomatic implants were placed on maxilla models at the location of first premolar and second premolar tooth, assembly of the modeled parts were completed. The data were processed by ANSYS Workbench software, 150N vertical occlusal and 300N masseteric load were simulated on modeled prosthesis. The Maximum Von Mises Stress in bone/implants and deformations were visualized and comparatively evaluated with color distribution scale. Conclusion: Cortical bone thickness, defect size and localization are among the factors closely related to the stability and success of the implant. Keywords : Zygomatic implant, quadrant zygoma, maxillary defect, finite element analysis

A COMPARATIVE STUDY TO EVALUATE THE RETENTION OF CONVENTIONAL AND CAD/CAM FABRICATED BAR ATTACHMENT IMPLANT SUPPORTED ASSEMBLY (IN VITRO STUDY)

Introduction: The use of implant-supported overdentures is a common approach for treating edentulous mandibles. Retention and stability are provided through attachments; bar attachments being probably the most retentive due to greater mechanical stability and better wear resistance. Micro and macro movement between the retentive surfaces of an attachment during mastication, insertion and removal will lead to wear and decrease of the retentive capacity. Using CAD/CAM technology should produce more precise frameworks with better retention. Objectives: was to compare the retention of different Cobalt Chromium bar attachments fabricated by CAD/CAM technology and conventional methods. Materials and methods: Two bar attachments of different method of fabrication were studied. The bars were divided into two different groups according to whether the bar was fabricated using the conventional method or CAD/CAM technology. The retention provided by each bar was tested using Universal testing machine. The difference in retention was compared between the groups. Results:Data was collected, tabulated and statistically analyzed using the appropriate test. Group 1 needed 32.91N dislodging force. Group 2 needed 62.8N to separate the clip from the bar Conclusions: CAD/CAM fabricated bars showed a significantly higher retentive force in comparison to conventional bars.

EVALUATION OF BITING FORCE FOR THREE DIFFERENT PARTIAL DENTURE MODALITIES IN BILATERAL DISTAL EXTENSION CASES (CROSSOVER STUDY)

The purpose of the present study was to assess the magnitude of biting force in three different partial denture designs. Methodology: A total of ten patients with mandibular bilateral free end saddles without modification (Unmodified class I) were included in this study. All patients received three successive partial denture designs (conventional, extra-coronal attachment and posterior implant with bar attachment successively). Each design was used for 4 months intervals. The mean biting force was measured at the time of insertion and after 4 months for each design. Results: One way ANOVA followed by Post Hoc test was made to check the significance within each group and between groups of different designs for the biting force measurements. The data revealed that the magnitude of biting force at insertion was 44.425+6.21398, 84.1050+5.93779 and 129.1900+7.92749 for conventional, extracoronal attachment and implant bar attachment design respectively, while after 4 month it was 49.4900+5.41002, 90.1850+6.36713 & 142.5700+7.49098 for conventional, extracoronal attachment and implant bar attachment design respectively. Conclusion: Within the limitation of this study it can be concluded that: 1- Using a posterior implant with bar supporting and retaining removable partial denture is a viable treatment option for free end saddle cases. 2- Significant improvement in biting force occurred by changing the design from conventional to extra-coronal attachment and from extra-coronal to implant bar attachment.

Milled bar versus rigid telescopic attachment for mandibular implant supported overdentures. A study of patient satisfaction and oral health quality of life.

Aim: This investigation aimed to evaluate participant satisfaction and quality of life of Milled bar versus rigid telescopic attachment for mandibular implant supported overdentures. Materials and methods: Eight edentulous participants who unsatisfied with the retention and stability of existing mandibular prosthesis received 4 implants in the interforminal area of the mandible using computer guided flapless surgical approach. After 3 months, implants were connected to overdentures with rigid telescopic (n=4) or milled bar (n=4) attachments. After 3 months of addaptation, patient satisfaction was measured using Visual analouge scale and Oral health related quality of life (OHEQoL) was measured using Oral health impact profile (OHIP-14). Comparison of data between groups were made using MannWhiteny test. Results: Milled bar showed significant higher satisfaction with overdenture retention than telescopic overdentures, while the later showed significant higher satisfaction with overdenture cleaning compared to milled bar. No significant differnce between the attachments was noted regarding other questionaire of VAS. Regarding OHIP, telescopic overdentures showed higher satisfaction regarding pronounciation of sounds, and comfort on eating than milled bars. No significant differnce between overdentures were noted for other OHIP questions Conclusion: Within the limits of this study, both telescopic and milled bar mandibular overdentures achieve high patient satisfaction and oral health related quality of life. However, milled bar overdentures are advantageous in terms of overdenture retention and telescopic overdentures are advantageous in terms of cleaning, comfort on eating and pronunciation of sounds.

COMPARATIVE EVALUATION OF MANDIBULAR OVERDENTURE WITH SINGLE CANINE SPLINTED OR UNSPLINTED TO IMPLANT ON THE ABUTMENT SUPPORTING STRUCTURES

The purpose of this clinical study was to evaluate and compare the effect of mandibular overdenture with single canine splinted or unsplinted to implant on the abutment supporting structures. Methods: Ten male patients, were included in this study from the outpatient clinic, Faculty of Dentistry, Misr University for Science and Technology, having only single standing mandibular canine opposing completely edentulous maxilla were selected. The selected patients were divided randomly by closed envelope into two equal groups according to their overdenture supporting system,: Group I: Patients received mandibular overdenture supported by natural canine and implant at the contra-lateral canine area. Group II: Patients received mandibular overdenture supported by natural canine connected by bar attachment to the implant at the contra-lateral canine area. The abutments were evaluated clinically and radiographically (marginal bone height and density changes). These evaluations were established at time of insertion, 6, 12 months. The data were collected and tabulated. Results: The implants in Both group showed successful clinical osseointegration till the end of the follow- up period. Conclusion: Within the limitations of this study, overdentures supported by the natural canine and an implant at the contralateral side of the arch had the best effect on the supporting structures of the abutments compared to the group of individuals with implant splinted by bar .

Radiographic Evaluation of Two Different Designs for Treatment of Mandibular Bilateral Free End Saddle with Osseo-integrated Implants

Purpose: Thegoal of this study was to evaluate radiographically two different designs for mandibular freeend saddle with osseointegrated implants.Materials and Method: Ten lower Kennedy class I partially edentulous patients were selected to receiveimplant at the second molar area, then patients were divided into 2 groups according to the implantsuperstructures either (extra-coronal attachment or bar attachment). Patients of both groups receiveremovable partial denture of the same design. Patients were followed up for 0, 3, 6 and 9 months clinically.Results: Showed statistical difference between the 2 designs.Conclusion: It could be concluded that Tooth-implant supported partial denture may be reasonable andsimple solution for Kennedy class I partial denture.

Nano-Hybrid Versus Micro-Hybrid Composite as Reinforced Resin for Ribbon Bar Attachment

Purpose: The goal of this study was to compare and evaluate stress transmitted to an overdenture abutment tooth supported by polyethylene ribbon bar reinforced composite resin of hybrid type, the hybrid type includes Nano-hybrid composite and Micro-hybrid composite. Methods: Edentulous educational acrylic model modified to receive two canine teeth and duplicated to ten models. Polyvinyl silicon impression material was packed to simulate mucosa covering the ridge. The canines prepared to receive a metal jacket and then infibra ribbon bar constructed on the abutments, mandibular overdenture constructed to each model over the bar, the ten models divided equally into two groups, Group I: Five models received mandibular overdenture supported by two canines splinted with ribbon fiber bar reinforced with Nano-hybrid composite. Group II: Five models received mandibular overdenture supported by two canines, splinted with ribbon fiber bar reinforced with Micro-hybrid composite. Installation of strain gauges around each surface of the abutment, Universal testing machine used to apply load to each model Unilateral (50 N) and bilateral (100 N) vertical static load applied at 1st molar area to measure µ-strains at buccal, lingual, mesial and distal surfaces of the abutment. the outcomes collected and statistically analyzed to compare between the two groups. Result: -Infibra ribbon bar reinforced by Nano-hybrid composite and infibra ribbon bar reinforced by micro-hybrid composite exhibits No significant difference of microstrain transmitted to overdenture abutment except the labial surface. - Under bilateral loading, Infibra ribbon bar reinforced with a Nano-hybrid composite bar transmit higher microstrain to all labial, lingual, and mesial surfaces of overdenture abutment than infibra ribbon bar reinforced with Micro-hybrid composite except the distal surface. Conclusion: -Infibra ribbon bar reinforced with hybrid type composite decrease stresses transmitted to mandibular overdenture abutment -Regarding stress distribution, Micro-hybrid composite is the material of choice to construct infibra ribbon bar over Nano-hybrid composite.

Bar versus Locator attachments for maxillary implant overdentures opposed by implant supported mandibular overdentures. Clinical and radiographic evaluation

Purpose: The aim of this short-term clinical trial was to evaluate clinical and radiographic outcomes of Bar and Locator attachments used to retain maxillary implant overdentures opposed by implant supported mandibular overdentures. Material and methods: Ten patients wearing conventional maxillary denture and implant supported mandibular overdentures received 4 implants in the maxillary arch using 2 stage surgical approach. Six months later maxillary overdentures were connected to the implants with locator (group 1) or bar (group 2) attachments. Plaque index, bleeding index, probing depth, implant stability, and marginal bone loss (using Cone beam computerized tomography) were evaluated at time of overdenture delivery, 6 months and 12 months later. Results: Plaque and gingival indices increased significantly with time in bar group only. Bar overdentures recorded significant higher plaque and gingival scores than locator overdentures. No significant difference in pocket depth and implant stability was noted between time intervals or groups. Total marginal bone loss for locator group was significantly higher than bar group after 6 and 12 months. For both groups, marginal bone loss around canine implants was significantly higher than bone loss around premolar implantsConclusion: Within the limits of this study, it could be concluded that both locator and bar retained maxillary overdentures are successful treatment options for patients complaining from instability of maxillary dentures opposed by implant retained mandibular denture. However, locator attachments are advantageous in terms of peri-implant soft tissue health and bar attachments are advantageous regarding peri-implant alveolar bone preservation.

A systematic review and meta-analysis of the attachments used in implant-supported overdentures.

Aim:To evaluate the survival rate, tissue response, and patient satisfaction of different attachments used in implant overdenture.Settings and Design:Systematic Review and Meta-analysis.Materials and Methods:Electronic search of peer-review articles published between 2001 and 2019 assessing the attachments used for implant-supported overdentures was done according to PRISMA Guidelies. The review evaluated sixteen articles related to survival of the attachments, the reaction of the soft and hard tissues along with repair and maintenance of the attachments, and overall performance of the overdenture attachments.Statistical Analysis Used:There is statistically significant heterogeneity (Q =374.7403, df = 15, and P < 0.0001). The statistics of fixed-effect model reported an MD of − 0.0880 (95% CI = −0.1536; 0.0225).Result:The review evaluated the 16 articles that met with the inclusion and search criteria. The studies were the combination of bar and ball attachments and their subtypes, magnetic and bar attachments, and locator in combination with other attachments. The meta-analysis of combined 16 studies reported acceptable heterogeneity among 16 studies (I 2 = 96%) and reported to be statistically significant (P < 0.01).Conclusion:The survival rate of attachments was in the range of 95.8%–97.5% for bar, 96.2%–100% for ball, 90%–92% for magnet and locator attachments were in the range of 97% after a mean follow-up period of 3 years. The bar attachments reported moderate tissue reaction in the form of mucosal changes, gingival inflammation, and bone resorption. The locator attachments require higher maintenance and repair. The magnetic attachments produce higher bone resorption and readily displace under functional force. Patient satisfaction and compliance was higher for ball, locator, and bar attachments as well as low for magnetic attachment. Thus, the ball and locator attachments excellently perform in terms of survival rate, tissue response, and patient satisfaction.

Studies of the Sediments of the Sea of Azov (on the Example of Dolgaya Spit)

The coast of the shallow Azov Sea is characterized by a series of sand spits. Based on the results of drilling conducted on Dolgaya Spit, which separates the water area of Taganrog Bay from the rest of the Sea of Azov, we consider the structure of the upper part of the geological section of these coastal accumulative forms. Core samples obtained during drilling made it possible to determine the change in thickness of Holocene sand-shell deposits and underlying Middle Pleistocene layers. It is shown that the formation of the spit began more than 5 ka ago during the initial stage of the New Black Sea transgression and occurred as a result of sequential attachment of beach bars to it.