Implant Supported Fixed Prosthesis PDF

implant 1 implant supported fixed prosthes is - alloplastic material implanted into the oral tissues beneath the mucosal and/or periosteal layer and on/or within the bone to provide reten...

implant 1 implant supported fixed prosthes is - alloplastic material implanted into the oral tissues beneath the mucosal and/or periosteal layer and on/or within the bone to provide retention & support for a fixed Or removable dental prosthesis.hey are devices inserted into Or onto the bone to support tooth replacement. * alloplastic materials → material originating from a non-living source that surgically replaces missing tissue Or augments that which remains - it is depending on osseointegration concept “process of direct attachment & connection of osseous tissues to an inert alloplastic material without intervening fibrous soft tissues in-between".  fibrous soft tissues presence bet. the host tissue & the inert alloplastic material is called fibro- integration & counted failure. * indications : 1- intact dentition with a missed single tooth. 2- long edentulous span. 3- inability to make FPD Or RPD. 4- unfavorably number & location of natural abutments. * contraindications : 1- systemic illness. 2- radiation therapy on the implant site. 3- less motivated pt. 4- lack of operator experience. 5- pregnancy. 6- uncontrolled metabolic disease. 7- unrealistic expectation of the pt. * advantages : a- surgical 1- documented success rate. 2- in-office procedure. 3- precise implant site preparation. 4- adaptable to multiple intra oral locations. 5- reversibility in the event of implant failure. b- prosthetic 1- multiple restoratives options. 2- angle correction. 3- screw Or cement-retained options. 4- esthetics. 5- versatility of second stage components. 6- crown contours. 7- retrievability in case of prosthodontics failure. ynf3 asl7ha 2023 Dr_M.Bedawi implant 2 classification of implants - acc. to position : 1- subperiosteal. t7t mucosa fo2 bone-m3 complete denture 2- transosteal. throughbone ben ely t7t w ely fo2  these 2 types anchor dentures in completely edentulous pt. 3- endosteal  used for partially edentulous pt. - it is surgically placed within alv. bone Or basal bone. - acc. to endosteal shape : 1- blade form : - wedge shaped implant. - rectangular shaped implant. 2- root “cylindrical” form : - it has a direct connection “osseointegration”. - 3 - 6 mm in diameter & 8 - 20 mm long. - often with external threads. - acc. to endosteal surgical procedures : 1- one stage implant : - implants are designed to be placed into the bone immediately & immediately project through the mucosa into the oral cavity. 2 - two stages implant : - first visit → placing the implant fixture in the bone to the level of the cortical plate & then, the oral mucosa is sutured over it. - left for a healing period (depending on the quality of bone). - 3 months for the mandible & 6 months for the maxilla. - second visit → mucosa is reflected from the superior surface of the implant. - an extension collar Or healing cap that projects into the oral cavity is fixed firmly to the implants. - acc. to materials :  acc. to the material : 1- metallic implant → Titanium, Titanium alloy. - nowadays they are the material of choice for the whole implant systems. - they can b threaded Or non threaded. - grit-blasted Or acid etched to roughen the surface & increase the area for bone contact. a surface pre-treatment that removes rust and surface contaminants from a metal component prior to powder coating or adding another protective coating. forcibly propelling a stream of abrasive materialunder high pressure against a surface to clean or modify its surface properties 2023 Dr_M.Bedawi implant 3  the ability of implant to stimulate bone formation with hydroxyapatite coating have the highest bio-functionality than implants without hydroxyapatite coating "bioactive". 2- metallic implant → Zirconia.  acc. to surface configuration : - cylindrical. - tapered.  threaded gives better stability to implant in bone than non threaded configuration. ttt planning for implants clinical examination 1- to determine if there is enough bone. 2- to identify anatomic structures & detect any flabby tissue, sharp bone & undercuts. radiographic examination 1- panoramic radiographic  is necessary to trace vital structures "maxillary sinus". - in panoramic view, a small R.O reference object, such as a ball bearing, was usually placed near the proposed implant site during exposure, enables the practitioner to control variation in magnification (5% - 30%).  new panoramic radiography machines have standardized enlargement ratios, therefore, correction markers are less necessary. 2- periapical radiographs → to evaluate areas of implants placement. 3- cephalometric radiographic  for bone width determination - anterior area of maxilla & mandible.  posterior maxilla & mandible bone width → clinical exam. 4- C.T scan  to show location of maxillary sinus, inferior alv. canals & other vital structures. diagnostic cast examination - to evaluate size of edentulous area. - to analyze maxillary-mandibular occlusal relationship. - construction of radiographic reference stent. - construction of surgical stent (resin template) after diagnostic waxed-up.  a resin template can be made from the cast to guide the surgeon during implant placement. probing “Bone Sounding” - using the pd. probe, needle Or sharp caliber till reach bone, to judge soft tissue thickness.  it is done under local anesthesia. 2023 Dr_M.Bedawi implant 4 restorative considerations anatomic limitations - implants must be placed totally within the bone & away from any anatomic features. - ideally, 10 mm of vertical bone & 6 mm of horizontal bone should be available for implant.  to allow for 1 mm of bone lingually & 0.5-1 mm buccally of the implant. Maxilla Mandible anterior posterior anterior posterior - 1 mm from nasal vestibule. - 1 mm away from - 5 mm from - 2 mm above superior - away from midline "to be floor of max. sinus. mental nerve. aspect of the inferior away from incisive foramen". alv. canal. - if inadequate length of bone is present → use short implants (8-10 mm) & ↑ number of implants and the healing period is ↑. implant placement - implant placement is important for the future restoration as it dictates the appearance, contour & function of the prosthesis. - distance bet. implants → minimum 3 mm & distance bet. implant & natural tooth→ minimum 1 mm "to ensure bone viability bet. Implants, to allow adequate oral hygiene once the restorative procedures are complete & implant must not encroach on the embrasure space".  if a restoration is placed too close to the adjacent tooth → compromised contours, loss of adjacent hard tissues & crushed interdental papilla.  placing the restoration too far from the adjacent implant → unfavorable contours & development of cantilever forces on the implant. - the implant should be placed in central fossa of the restoration “to  harmful lateral forces”. - the superior surface of the implant must be 2 - 3 mm inferior to the emergence profile of the planned restoration.  implant is not placed deep enough → the crown will be short & over contoured.  placing the implant too deep → excessively deep gingival sulcus. implant size - acc. to size of the lost tooth, we should choose the suitable size of the implant diameter.  for small diameter teeth “lower centrals”  small diameter implant 3 mm.  for molars  large diameter implant 5-6 mm. soft tissue contours - achieving a completely well formed papilla bet. the implant restoration & the adjacent teeth in the final outcome is mandatory for esthetics. 2023 Dr_M.Bedawi implant 5 - distance bet. interdental bone & the interproximal contact is important for ideal papillary contours. - if distance ↓ 5 mm  papilla is usually present. - if distance ↑ 8 mm  papilla would not normally without additional grafting. single tooth implant - treatment planning for single implant restoration, particularly in the anterior esthetic zone, is one of the most challenging problems. - it should achieve both esthetic & function.  it needs an anti-rotational feature built into the system to prevent rotation. clinical implant components 1- implant body “fixture body” - the root form part ẁ is placed within the bone during the 1st stage surgery. - implants have an internally threaded portion that can accept second-stage screw placements.  it needs an anti-rotational feature built into the system to prevent rotation. 2- healing screw “cover screw” - screwed over the implant body at the end of 1st surgery to occlusal surface during osseointegration. - formed from Ti Or Ti alloys. - can be larger than the implant body to seal it & prevent bone and soft tissues from growing over the implant. 3- healing cap & healing abutment - it has a dome-shaped 2-10 mm length “project through soft tissue”. - placed at the end of second surgery, before placement of the abutment. - formed from resin, Ti Or Ti alloys. - it is important for esthetic to allow for better tissue healing “guide gingival healing”. - in esthetic zones, 3 - 5 weeks may be required before abutment selection.  if esthetic is not critical, adequate healing for impressions usually takes 2 weeks. 4- abutment - the part of the implant system ẁ screws directly into the implant body & support prosthesis by screw Or cement. - made of Ti, Ti alloys Or Zr. - available in lengths from 1-10 mm. 2023 Dr_M.Bedawi implant 6 union - if implant system is incorporated with an anti-rotational feature, the abutment will have 2 components that move independently: one engaging the anti-rotational feature & the other securing the abutment to the fixture sodasy - for a multiple unit restoration, the hexes usually can`t be “engaged” due to lack of parallelism of the implants. So non-engaging direct abutments must be used. * types  screw-retained "standard" abutments - implant system has 2 screws → the first screw is to attach the abutment to the implant, while the second screw attaches the abutment to the restorations. - length can be selected to make the margin supra-gingival Or sub-gingival.  screws : secures fixed restoration to the abutment. - formed from Ti, Ti alloys Or Au alloys. - short Or long. * indications : - when retrievability of the implant prosthesis is planned. * contra-indications : a- in case of inadequate inter-arch space "no space for the regular components". b- when maximum esthetics is needed.  screw access opening is filled with composite resin material → affect esthetics of restoration occlusal portion. * adv. : ymkn esrga3o 1- retrievable "allows for sulcular debridement & checking". 2- no need for luting cement. 3- connection to machined abutments. * dis-adv. : 1- may loosen during function.  to prevent this, anti-rotational feature Or a mechanical interlock is used. 2- difficult to achieve good emergence profile. 3- may ↓ esthetics. 4- more liable to porcelain fracture.  cement-retained "fixed" abutments - it retains the final restoration with cements. - they will resemble tooth preparation → smooth, polished & straight sided. - use a temporary cement → to allow retrievability. 2023 Dr_M.Bedawi implant 7 * indications : - inaccessible areas. - mainly in posterior regions where accessibility with screw drivers might be difficult. * contra-indications : - in case of inadequate inter-arch space.  minimum of 5-7 mm of the abutment must be exposed in the oral cavity to provide a retentive restoration. * adv. : 1- cementation ensure passive adaptation of the final restoration. 2- cement will act as shock absorber & lower stress at implant/bone interface. * dis-adv. : - difficult to remove excess cement, it may cause peri-implantitis. - irretrievability if permanent cement is used.  angled abutments - available in cement types & screw types. - allows correction of angulation problems for esthetic Or biomechanical reasons. - the best angulations can be selected ranging from 15-35.  not used for regular use to avoid tipping destructive forces on implant. * adv. : - ↑ esthetics - correction of divergent placed fixtures. - avoiding anatomic structures. - facilitates oral hygiene. - screw access on the occlusal surfaces.  tapered "wide-based" abutments - used for both esthetics & function reasons. - allow more gradual transition to restoration, allowing teeth with larger cross sections to be restored with → more proper contours, more stability & better emergence profile.  non-segmented Or UCLA abutments b3mlha b mzage - Unique Castable Long Abutment Or Universal Clearance Limited Abutment. td5l - no intervening abutment "one-piece prosthetic component"→ restoration built directly on implant. - restoration directly placed on the implant. * indications : 1- in esthetic areas, when soft tissue thickness is minimal  2 mm. 2- in limited inter-arch distance. 2023 Dr_M.Bedawi implant 8  3 mm is sufficient for this type of restoration, while other abutments require 8 mm. - supplied in either totally castable plastic tube Or combination of Au alloy base & plastic extension.  it can correct angles up to 30o as being a custom abutment.  computer generated abutments - they are machined in Ti, precious alloys & all ceramic ẁ are custom made by CAD-CAM system. - they can provide most accurate fit.  choice of abutment size depends on : 1- the vertical distance between the fixture base & opposing dentition. 2- the existing sulcular depth. 3- the esthetic requirements in the area being restored. - for acceptable appearance : - fixtures in the posterior part of the maxilla Or mandible may require margin termination at or below the gingival crest. - for an anterior maxillary crown, 2 to 3 mm of subgingival porcelain at the facial gingival margin is required to create the proper emergence profile needed to optimize final restoration contour and appearance.  the success factors : 1- a-traumatic surgery. accurate 2- precise placement. 3- unloaded healing. 4- passive restoration. 5- impression post “transfer coping” - facilitate transfer of intra oral location of implant fixture to the cast. - screwed into the implant then an overall impression using heavy body impression. 6- laboratory analogue - represent exactly the top of the implant fixture. - screwed to impression post & placed in its place on impression before pouring. implant restorative options 1- distal extension implant restoration - place two implants distal to the most posterior tooth & fabricate implant supported FPD - if Cr/imp. ratio is favorable , 2 implants to support a three units FPD.  if implant are short & crowns are long, 1 implant to replace each missing tooth is highly recommended. 2023 Dr_M.Bedawi implant 9 2- long edentulous span restoration - place multiple implants bet. the remaining natural teeth & fabricate implant supported FPD - place one Or two implants in the long edentulous span & the final restoration connected to natural teeth after being protected with telescopic copings to maintain retrievability (min. bone resorption). - fabricate a hybrid prostheses ẁ requires the restoring of soft & hard tissue in addition to teeth.  in these instances, using resin teeth processed to a metal substructure rather than a conventional metal- ceramic restoration, are recommended. 3- single tooth implant restoration * requirements for single tooth implant crown : - Esthetics. - Anti-rotation to avoid prosthetic component loosening. - Simplicity: to minimize the amount of components used. - Accessibility: to maintain optimum oral health. - Variability: to allow the clinician to control the height , diameter & angulation of the implant restoration. - Matching soft tissue contour of adjacent teeth remains the most difficult challenge. - Indicated in congenitally missing upper lateral incisors, otherwise Intact dentition & multiple spaces that difficult to be treated with conventional FPD. 4- fixed restoration in completely edentulous arch - minimum of 5 implants in the mandible & 6 implants in the maxilla. - in case of moderate bone resorption , a hybrid prosthesis is fabricated using processed resin teeth. - in case of minimal bone resorption , a C-M prosthesis is fabricated. biomechanical factors affecting implant success 1- occlusion - implant restoration should be designed to minimize damaging forces at the implant-bone interface. - premature loading Or overloading → bone resorption. - direction of forces applied on implants : - direct forces in the long axis of the implant minimize lateral forces on the implant - as a rule, place lateral forces when necessary, as far anterior in the arch as possible. - cusp to fossa relationship with no eccentric occlusal contact should be established. - ↑ implant angles → ↑ stresses at bone-implant interface → ↑ bone resorption. - inadequate implant distribution → over loading of implant bodies. - dental implants should be joined to equally distribute the forces over multiple implants. 2023 Dr_M.Bedawi implant 11 - if short implants → 1 implant for every tooth to be restored. - if long implants (more than 13 mm) → 2 implants for every 3 teeth to be restored. - full arch → no less than 6 implants in the maxilla & 5 implants in the mandible. 2- connecting implants to natural teeth - creates excessive forces due to the relative immobility of the osseointegrated implant compared to the functional mobility of natural teeth. - during function, the tooth moves within the limits of the pd. ligaments ẁ creates stresses at the neck of the implant up to 2 times & this stresses can cause : a- breakdown of the osseointegration. b- cement failure. c- abutment loosening. d- implant failure.  to solve this problem : - multiple implants Or natural abutments should be used. - semi-precision attachment in the prosthesis bet. implant & the tooth may solve this problem. - use of telescopic coping which is permanently cemented to the natural tooth. - provisional cement is used to attach the prosthesis to the coping. - So if it will leach out of the implant crown, natural crown will still be protected. maintenance - recall visits once per 3 months during the first year. - sulcular debridement must be done with plastic Or wooden scalers “metal instruments scratch Ti”. - we should rely on proper home care measures. - we must teach the pt the hygienic instructions. - implant mobility, framework fit & occlusion should be evaluated. complications a- bone loss - any loss exceeding 0.2 mm/year is a cause of concern.  if it reaches 25%, surgery must be remake.  factors associated with bone loss 1- improper size, shape Or number of implants. 2- inadequate amount of bone. 3- inadequate fit Or design of the prosthesis. 4- excessive occlusal force. 2023 Dr_M.Bedawi implant 11 5- systemic influence “tobacco & diabetes”. 6- inadequate oral hygiene. b- prosthetic failure - fracture of implant components Or of the prosthesis due to fatigue from biomechanical overload Or due to wrong design. - loose restoration-retaining Screws : 1- excessive occlusal contacts not within the long axis of the implant body. 2- excessive cantilevering force. Dr_Mohammed Bedawi 2023 Dr_M.Bedawi