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The Marius Implant Bridge: Surgical andProsthetic Rehabilitation for the CompletelyEdentulous Upper Jawwith Moderate to SevereResorption: A 5-Year Retrospective Clinical StudyYvan Fortin, DDS;* Richard M. Sullivan, DDS; Bo R. Rangert, PhD, MechEngtABSTRACTBackground: Patients seeking replacement of their upper denture with an implant-supported restoration are most interested in a fmed restoration. Accompanying the loss of supporting alveolar structure due to resorption is the necessity forlip support, often provided by a denture flange. Attempts to provide a fxed restoration can result in compromises to oralhygiene based on designs with ridge laps. An alternative has been an overdenture prosthesis, which provides lip supportbut has extensions on to the palate and considerations of patient acceptance. The Marius bridge was developed as a fmedbridge alternative offering lip support that is removable by the patient for hygiene purposes, with no palatal extensionbeyond normal crown-alveolar contours.Purpose: Implant-supported restorative treatment of completely edentulous upper jaws, as an alternative to a completedenture, is frequently an elective preference, and it requires significant patient acceptance beyond the functionalimprovement of chewing. Patients with moderate to severe bone resorption and thin ridges present additional challengesfor adequate bone volume and soft-tissue contours. The purpose of this investigation was to develop a surgical and prosthetic implant treatment protocol for completely edentulous maxillae in which optimal lip support and phonetics isachieved in combination with substantial implant anchorage without bone grafting.Materials and Methods: The Marius bridge is a complete-arch, double-structure prosthesis for maxillae that is removableby the patient for oral hygiene. The first 45 consecutive patients treated by one person (YF) in one center with this concept are reported, with 245 implants followed for up to 5 years after prostheses connection.Results: The cumulative fwture survival rate for this 5-year retrospective clinical study was 97%. Five fixtures failed beforeloading, in five different patients, and two fwtures in the same patient failed at the 3-year follow-up visit. None of thebridges failed, giving a prostheses survival rate of 100%. The complications were few and mainly prosthetic: nine incidences of attachment component complications, one mesobar fracture, and three reports of gingivitis. All complicationswere solved or repaired immediately, with minimal or no interruption of prostheses use.Conclusions: Satisfactory medium-term results of survival and patient satisfaction show that the Marius bridge can be recommended for implant dentistry. The technique may reduce the need for grafting, because it allows for longer implantsto be placed with improved bone anchorage and prostheses support.KEY WORDS: clinical follow-up, complete arch, double structure, esthetics, maxilla, phonetics, tilted implantsThe possibility of a n esthetic fured prosthesis supported by osseointegrated implants remains one ofthe most remarkable achievements in clinical dentistry.I4 However, successful implant-supported restorative treatment of completely edentulous Upper jaws asan alternative to a complete denture requires significantpatient acceptance beyond the functional improvementof chewing, because it frequently is an elective preference rather than a functional requirement. People seek-*Centre d’Implantologie Dentaire de Quebec, Ste-Foy, Quebec,Canada; Clinical Director, Nobel Biocare USA, Yorba Linda, California, USA; and Chief Scientist, Nobel Biocare AB, Gothenburg,SwedenReprint requests: Yvan Fortin, DDS, 3075, chemin des QuatreBourgeois, Bureau 109, Ste-Fob Quebec G1W 4Y5, Canada; e-mail:yvan@drfortin.com02002 BC Decker Inc69
70Clinical Implant Dentistry and Related Research, Volume 4, Number 2,2002ing this treatment often have well-functioning upperdentures, and their pursuit of an implant-supportedbridge may be based on psychological reasons involvingself-image, perception of aging, and acceptance by others. Several authors have detailed the diagnostic andimplant prosthodontic criteria for successful treatmentoutcomes for this indi ation. -’ Resilient overdentures retained by dental implantshave been used as an alternative to a fKed bridge.13-16 Avariation of the overdenture is the double-structureapproach, presented in various fashions, includingwhat has become known as a spark-erosion prosthesi .l’- lThe overdenture and double-structure designintroduce a substantial degree of freedom in implantposition and direction without compromising theesthetic outcome, compared with the more exactingplacement required for a fmed prosthesis. An advantageof this flexibility of positioning is that the implants maybe more optimal with respect to bone anchorage. However, disadvantages with the maxdlary overdenture andspark-erosion variation observed by the authorsinclude an undesirable bulk in contour on the palatalaspect and prosthesis instability after years of use.Another important restriction for complete-archimplant prostheses in the maxilla is the often limitedamount and quality of bone available at the site ofimplant placement.22Radiographically, the maxilla mayshow available height of bone, but owing to the resorptive pattern, the residual ridge is often too narrow in alabial-palatal dimension for implant placement. Onlaybone grafting has been used to overcome this deficiencyin bone o l u m e . The -technique of implant tiltingin the maxillary arch has been clinically documentedand demonstrates a viable technique for improvingbone anchorage and prosthesis support, while oftenavoiding bone grafting p r o c e d r e s . - The Marius reconstruction (named after the firstpatient treated with this modality) is a specific doublebridge structure. It was developed during a search for amethod to provide routine fixed solutions for the completely edentulous upper jaw, to provide estheticanatomic contours when restoring hard- and soft-tissuedeficits, without the necessity of bone grafting procedures. The concept is based on four factors:1. The ability to place fEtures in the posterior regionalong the anterior ascending wall of the maxillarysinus,The ability to place fEtures in the anterior regionadjacent to the incisal foramen,Useof an anterior undercut in the bridge mesobar3.to provide primary retention for the superstructure, and4. Presentation to the patient as a fixed bridge, yetremovable for oral hygiene purposes2.The aim of this article is to present a method thatevaluates the functional outcome and patients’ satisfaction with the use of Marius reconstruction relative tothe hypothesis that this treatment modality combinesthe advantages of an overdenture and a fixed bridge foredentulous maxillae.MATERIALS AND METHODSPatientsResults from the first 45 consecutive patients treatedwith the Marius bridge are presented. The patientsincluded in the study were treated by one person (YF)in one clinic. All patients were completely edentulousin the upper jaw and candidates for implant treatmentwho fulfilled the following inclusion criteria:Necessity of lip support or position of the lipwhen smiling, requiring a flange extension to theprosthesis, andSufficient bone available for placing implantswith a minimum diameter of 3.75 mm, in tiltedposition if desired, in positions suitable to support a fixed bridge.The patients were shown the alternative of theMarius bridge, using a well-produced model, and theconcept was presented as a fixed bridge that is removable by the patient for oral hygienic purposes. Exclusion criteria were those generally used when candidatesfor implant treatment are selected.31The patients were treated with a total of 245 implants(Brinemark System@,Nobel Biocare AB, Gothenburg,Sweden). The vast majority (n 43) of the patients hadbeen edentulous in the maxilla for over 5 years. Thefirst implant was placed in May 1991 and the last one inJune 1994. The first bridge was placed in April 1993and the last one in May 1995. Data from the patients’treatment were retrospectively followed from recordsbefore July 1, 1995; after that time, follow-up was conducted according to a standardized format.
The Marius Implant Bridge 71There were 15 male and 30 female patients in thestudy. The age distribution is given in Table 1, and bonequality, according to Lekholm and Zarb,32 estimatedfrom presurgical radiographs and surgical assessment,is given in Table 2 . The implant positions in the jawsare described in Table 3 and implant lengths in Table 4.The reasons that patients gave for their choice of treatment are given in Table 5, and the number of implantsper bridge is described in Table 6 .TABLE 2. Bone Quality According t o Lekholmand Zarb32Bone Quality123Implants (n 245))0-1114111Implants lost (n 7)42321TABLE 3. Positions o f Maxillary ImplantsSurgical AspectsIncisor* Canine Premolar or MolartThe surgical approach for the Marius bridge recognizesthat in the moderately to severely resorbed maxilla, theresidual bone ridge is often too thin to allow straightplacement of 10-mm or longer dental implants, especially for posterior support. In these situations, tiltedimplants are used in the posterior, following the anteriorwall of the maxillary sinus. These posterior tiltedimplants are considered to be significant in the structuralfoundation for the nonresilient fixed restoration and arereferred to as posterior bodyguard implants to differentiate them from other posterior implants that may beplaced. After posterior bodyguard implant placement,appropriate sites for anterior implants on each side lateral to the incisal foramen are identified; these twoimplants are also considered critical to the structuralsupport and are referred to as anterior bodyguardimplants. Only after these four implants are placed areother sites considered, based on available bone.All implants (Brinemark System) were placed following the general principles of Br?inemark?2 The surgical preparation began with the posterior implants at eachside, placed in the pyramid of bone anterior to the maxillary sinus. These pyramids are composed of the anteriorwall of the sinus, the buccal plate, and the palate (Figure1). The sites were begun on the palatal side of the crest.There was only one pass made with the 2-mm and3-mm twist drills to minimize the risk of overprepara-Implants (n 245)Implants lost (n 7)891660 *Anteriorbodyguard; posteriorbodyguard.tion, with the preparation directed following the anteriorwall, attempting to allow the cortices to guide the drilldirection upwardly and anteri rly. - OUse of the pyramid of bone anterior to the maxillary sinus also allowsTABLE 4. I m p l an t LengthsImplant Length(mm)Implants(n 245)Implants Lost(n 7)62000578.51012131518Unknown17286871154000TABLE 5 . Patients' Reasons for TreatmentChoiceReasonNumber of Patients (n 99)*Phonetic11173041EstheticTABLE 1. Patient Age DistributionAge (Y)18-303 1-4041-5051-6061-707 1-80Number (n 45)11021751906PsychologicalFunctional*Somepatients had a combination of two or more reasons.TABLE 6 . Number o f Implants per BridgeNumber of lmolants34567Number of bridges1108251
72Clinical Implant Dentistry and Related Research, Volume 4, Number 2, 2002Figure 1. The three-dimensional pyramid of bonethat is often located anterior to the maxillary sinuswall. This pyramid is suitable for the placement ofone tilted implant following the inclination of thecortex of the anterior sinus wall and medial to thebuccal plate. (CT scan courtesy of D. Levitt, DDS.)treatment of patients with otherwise knife-edge ridgesthat would be too thin for implant placement. Theimplants were tightened with a minimum of 30 Ncmtorque resistance, and no more than two exposed threadson the palatal aspects of implants were present. This procedure led to stable posterior implants with the headsroutinely emerging in the second premolar locations(i.e., posterior bodyguards) (Figure 2).Following placement of the posterior bodyguards,two implants were placed anteriorly on either side of theincisal foramen, as could be accommodated by availablebone. A pyramid of bone generally lies on either side ofthe incisive foramen, extending superiorly and followingthe direction of the canal. These anterior bodyguardimplants follow the natural profile of each pyramid oneither side of the canal. Four implants were aimed for,with additional implants added only if bone volumeallowed further placement between the four implantsfirst placed. Often additional implants could not beplaced in the canine site, because the anterior extensionFigure 2. A, Radiograph demonstrating tilting of posterior bodyguard implants. B, Occlusal view of mesostructure showing flexibility inposition of implant placement. Note distal inclination of both posterior gold screws following the axial orientation of implant placement.
The Marius Implant Bridge 73Figure 3. Four implants is the minimum goal fora fxed restoration in the fully edentulous maxilla.Often the maxillary ridge is too thin to allowplacement of intermediary implants without onlaybone grafting.of the bodyguard implant occupied its superior aspect(Figure 3), or the residual ridge was too thin to allowimplant placement without onlay bone grafting.ogy and flows with the palate contours, allowing propertongue spacing with minimal encroachment (Figure 7).Survival Criteria and Follow-upRestorative AspectsThe Marius bridge is fully implant supported, with noresiliency incorporated into the design, even though thepatient can remove the bridge superstructure. Thisallows for an anterior flange for lip support in a fEed,stable design that is still removable for patient hygieneaccess (Figure 4). The bridge uses a cast mesostructureand superstructure incorporating an approximately 20degree anterior angle and a posterior locking mechanism (Figure 5). This anterior undercut serves severalfunctions. First, as the superstructure rolls around thismesostructure undercut upon insertion, this anteriorundercut provides primary retention for the entireprosthesis, even before the posterior locks (Mk I Universal Attachments, Sande, Germany) are engaged (Figure 6). The design of this anterior bar segment fitswithin the confines of upper incisor cervical morphol-A surviving implant was defined as an implant that wasclinically stable and fulfilled its purported functionwithout any discomfort to the patient.33 Once the treatment was finalized, the patients were asked about theirsatisfaction with regard to phonetics, esthetics, and psychological and functional aspects.The patients were assessed every 6 months afterbridge connection. The mesobar stability was checked atthe position of each implant and any complication registered. Implant mesobars were not routinely removed;however, if a gold prosthetic screw was found to beloose, the mesobar was removed and each abutmentscrew was individually assessed for tightness. Panoramicsurvey films were taken on an annual basis; no systematic bone level measurements were carried out, andintraoral radiographs were only taken in situationswhen needed to ascertain implant integration.Figure 4. A, Anterior view of Marius bridge Superstructure with fill flange extension. The Marius bridge uses a prosthetic means toprovide lip support and to correct soft-tissue deficits when sufficient bone is present for implant anchorage. B, Marius superstructurefrom above. Although an anterior flange is present, there is minimal bulk on the palatal aspect. The posterior locks protrude when theyare not engaged.
74Clinical Implant Dentistry and Related Research, Volume 4, Number 2, 2002Figure 5. Side view of mesostructure. Note approximately 20degree anterior undercut and circular receptacle for lock engagement. Once the superstructure is rotated around the anteriorundercut, the locks are placed through the mesostructure, withno resiliency present.DropoutsSix patients were withdrawn from the study: onepatient did not show up after prosthesis delivery, andfive were lost to follow-up after 2 years because theymoved far away or their addresses became unknown.Thirty-nine (87%) of the patients were followedthrough the complete study time, 5 years.RESULTSFive implants failed before loading (all in differentpatients), and two implants failed at the 3-year followup visit (in the same patient), giving the cumulativeimplant survival rate of 97% (Table 7). None of thebridges failed, giving a prosthetic survival rate of 100%.In situations where intraoral radiographs were taken,no radiolucent areas were observed.Figure 6. When the posterior lock is seated, the patient can easily verify complete seating with his or her tongue. The locks areeasily disengaged with a pin mechanism.All patients were satisfied with phonetics, esthetics,and psychological and functional aspects once treatment was completed. Thirty-nine of the patients considered their prostheses to be fured, whereas six considered them to be removable.There were only a few complications reported,mainly prosthetic: nine incidences of attachment component complications, one mesobar fracture, and threeobservations of gingival inflammation. All prostheticcomplications were solved or repaired immediately, andthe use of the prosthesis was only shortly interrupted, ifat all.DISCUSSIONThe 5-year cumulative survival rate of 97% comparesfavorably with historic material . It is believed thatthe reasons for the good result are the biomechanicaladvantages of the concept and the well-anchoredimplants placed in strategic positions from a loadsharing point of view.As bone loss was not systematically measured, theprobability for the implants to remain stable could notbe p r e d i t e dHowever,. the majority of implant lossesFigure 7. A, Side view of mesostructure with illustration overlaydemonstrating retention and lack of bulk, with bar tucked insidecervical morphology of anterior teeth. B, Occlusal view of seatedMarius bridge. Even though a full flange is present in the anterior,the palatal aspect is similar in contour to a fixed restoration onnatural teeth.
TABLE 7. Cumulative Implant Survival RateTime PeriodImplantsFailed Withdrawn CSR (%)Placement-loading2455098.0Loading-6 mo6-12 mo240098.023406012-18 mo2340098.098.018-24 m o23401198.024-30 m o22301798.030-36 mo2062097.060 mo2040097.0with the Brinemark System occur during healing or thefirst year of function”; therefore, because the patientsof the present study were followed for 5 years, the resultindicates that the concept is viable long term.Historically, implant treatment of the completelyedentulous maxilla has been evolving toward the placement of more implants than the standard four to siximplants originally introduced by the Brinemark team.However, from a bioniechanical point of view, placement of the two well-anchored posterior bodyguardimplants, with the addition of at least two more anterior bodyguard implants in the anterior segment, provides a predictable foundation for an implant-supported prosthesis.” The interfixture spread is favorable,cantilevers are minimized, and the posterior implants arewell anchored. In addition, it is easier to achieve a wellfitted prosthesis with fewer implants. This means thatlimiting the number of implants to four to six for thein axill ar y complete - ar ch pros t h e s i s helps to ensureoptimal mechanical stability. This principle, to use afew well-anchored and positioned implants rather thanthe maximum possible number of implants, is supported by clinical documentation in which the samesuccess rates for fixed bridges in both jaws for the fullarch prosthesis anchorage has been shown, whetherfour or six implants wereIt has been shown by intraoral iniplant load measurements that tilting of a n implant that is part of amultiple implant-supported bridge structure does notincrease bone stress per se.23 Therefore, placing ti
placement of 10-mm or longer dental implants, espe- cially for posterior support. In these situations, tilted implants are used in the posterior, following the anterior wall of the maxillary sinus. These posterior tilted implants are considered to be significant in the structural
The AMS 700 prostheses require some manual dexterity to inflate and deflate. 1.4 Possibility of malfunction The possibility of leakage, blockage, or device malfunction exists. 1.5 Possibility of changes in the penis or scrotum Implantation of a penile prosthesis may cause the penis to become shorter, curve, or be scarred.File Size: 710KB
Chapters 2 and 3 Lecture ˇotes I. Production Possibility Frontier (PPF) A. The Production Possibility Frontier (PPF) A recurring choice that appears in all economic systems is the choice between consumption today and consumption tomorrow. When you put money in a saving
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NOTICE: Procedures, which if not properly followed, create a possibility of physical property damage AND little or no possibility of injury. WARNING: Read the ENTIRE instruction manual to become familiar with the features of the product before operating. Failure to operate the product correctly can . 2 Read
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