Immediate Loading in Implant Dentistry: Surgical, Prosthetic, Occlusal, and Laboratory Aspects 848987333X, 9788489873339

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Immediate Loading in Implant Dentistry Surgical, Prosthetic, Occlusal, and Laboratory Aspects

Vicente Jimenez-Lopez, Private Practice Madrid, Spain

MD, DDS

Translated by Thomas P. Keogh, Jr. ret1red USAGS, and Thornas P. Keogh Ill. MD, DDS

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Editorial Quintessence, S.L. Barcelona. Chicago, Berlin, Tokyo, Copenhagen, London, Paris, Milan, Istanbul, Sao Paulo, New Delhi, Moscow. Prage, and Warsaw

Dedication To my rnends Ramon Mendoza and Vicente Jimenez (my rather): My thanks tor having let me learn trom your age and experience, your illness, your suffering, your knowledge and love of life. your tempered bravery, your company. your always sage advice. your insistence. your patience. your not-always-understood humanity, your personal charisma and generosity, your always timely criticism. your sense of humor. your engaging smile. your self-discipline. your joy at my successes and sadness at my failures. your understanding, your involvement, your lnendship and affection. You were friends who will live as long as I exist To my wife Pepa and my children Jaime. Silvia, David, and Pepa, for your love, sense ot family. alfect1on. unconditional support, and For being the way you are. To my mother.

Images used with permission of Nobel Biocare:

1-3; 1-4; 6-8. 6-48; 8-55b; 8-56; 8-57; 8-58; 8-59: 8-60: 8-61; 8-62: 8-63: 8-65; 8-66; 8-75: 8-76; 8-77; 8-78; 8-80. Images used with permission or Implant Innovations. Inc:

1-2 Images used with permission of Zimmer:

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© 2005 Editonal Ou1ntessence. SL Ed1lonal Ou•ntessence, SL Torres Trade (Torre Suri Gran Via Carles Ill. 84

08028 Barcelona Spain www.qu1ntessence es DepoSllO

legal &3384-05

ISBN: 8'1-89873-33-X All nghts reserved This book or any part thereof may not be reproduced. stored '" a retneval system, or transmitted 1n any form or by any means. electronic. mechafllcal. photocopymg, or oth0fWIS0. Without pnor written permlSSlon of the publrsher

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Contents

Foreword v11 Preface vi11 Acknowledgments tx

Contnbutors x

1

Introduction and General Considerations for Immediate Implant Loading 1

2

Surgical Technique for Immediate Loading of Single Implants

1s

Ricardo Fernandez Gonzalez Implant Placement 1n the Alveolar Process with Adequate Bone Height and Width Implant Placement Following Tooth Extraction Implant Placement 1n the Alveolar Process with Width and/ or Height L1m1tations Implant Placement Immediately Alter Extraction of an Impacted Tooth

3

Prosthetic Features of Immediate Implant Loading in Single Teeth 49 Extracted Tooth and Well-Preserved Alveolus. or Alveolus with M1n1mal Bone Loss Tooth Not Extracted and Well-Preserved Alveolus, or Alveolus with M1n1maJ Bone Loss Nonextracted Tooth and Alveolus with Substantial Bone Loss Extracted Tooth and Substantial Bone Loss Single Tooth Replacement 1n the Posterior Areas lnterrelat10nsh1p Between Ill and OrthodontJcs Patient Age

4

Implant Surgery for Immediate Loading of Hybrid Prostheses in the Mandible 11 Ricardo Fernandez Gonzalez Treatment Planning Surgical Technique Results

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Immediate Implant Loading for Overdentures and Mandibular Hybrid Prostheses 89 Overdentures Fixed Hybnd Prostheses Clinical Cases with Extractions and Immediate Loading

v

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Branemark Novum: Surgical and Prosthetic Procedure for Mandibular Immediate Loading 141 Jose Manuel Navarro Alonso. Begona Fernandez Ateca, and Ramon Martinez Corria Preoperatrve Evaluation Procedure Patients Treated with Branemark Novum Conclusions

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Immediate Implant Loading in Patients with a Completely Edentulous Maxilla 175 Paulo Mal6 Contributor: Maria Dolores Zampieri Patient Selection Clinical Evaluation Rad1otog1c Evaluation Treatment Planning Preoperative Protocol Surgical and Prosthetic Protocol for Immediate Provisional Prosthesis Postoperative Protocol and Rehab11itat1on Program Laboratory Procedures Possible Complications with an Immediate Provisional Prosthesis Clinical Case Final Observations

8

Laboratory Considerations

211 Vicente J1menez-L6pez and Santiago Dalmau Bejarano

Achieving a Good Master Cast Achieving a Blueprint of the End Product Design QI the Alloy Structure and Selection of the Recovering Material The Milled Titanium System: Procera Implant Prosthesis The Procera Titanium Abutment System The Procera Ceramic Abutment System Technique for Luling Crowns over a Metal Structure Technique for Screw-Retained Suprastructures and Infrastructures

g

Occlusion in Immediate Loading

251

Single-Tooth Replacement Partial Prostheses Maxillary or Mandibular Complete Fixed Rehabilitation Maxillary and Mandibular Fixed Rehabilrtation Occlusal Ad1ustment in Complete Implant.Supported Rehabilitations Nightguards B1b11ography 267

Index 275 VI

Chapter 1 Introduction and General Considerations for Immediate Implant Loading Vicente Jimenez-Lopez

The Idea of shortening the waiting time to solve a patient's esthetic and functional concerns with a fixed prosthesis has led many authors to address the issue of reducing the pre-established waiting periods while following the principles of osseointegration developed by Professor Br~nemark. Early studies focused on reducing the lime between extraction ·and implant placement. One to 2 months of healing were considered suff1cien1. in comparison to the 9- to 12-month waiting period previously required to allow for bone healing. The next step under scrutiny was the time that elapsed between the hrst surgery (implant placement) and the second surgery (uncovering the implants and placing abutments). Upon observation. clinicians determined that, with a suitable quality and quantity of penalveolar bone. the wa1t1ng penod could be decreased to 2 months. Interest then developed regarding what would happen If the first and second surgeries were combined into one step. Becker et al evaluated quality and quantity of bone in

1997. This 1-year study analyzing these parameters provided qurte an acceptable success rate-95.6%. The next unknowns to be resolved included not only lhe single surgical procedure but also the 1mmed1ate provision of a temporary acrylic restoration without function or tooth loading. which only partially resolved the esthetic problem. Within a variable time period. this prosthesis would be substituted for a final ceramic restoration. Why not 1n the posterior dentillon? Why not for fixed partial prostheses? Schnitman et al (1997) found 1n a 10-year study that immediate loading of implants was successful in 84. 7% of cases. The authors mentioned an unknown prognosis for immediate loading 1n areas distal to the 1nc1sors. Clin1c1ans who are involved with implant cases that involve extraction of lhe entire mandibular dentition followed by an Interim complete denture have encountered esthetic problems while trying to maintain these patients for the shortest time possible without a 1

Chapter 1 • Introduction and General Considerations for Immediate Implant Loading

prosthesis. The usual scenario was to wait for 2 months after extraction until implant surgery could be performed, wait at least 1 week unul the patient could use the provisional prosthesis. and then wall for 4 months unltl second-stage surgery_ Meanwhile. this scenano caused enormous patient discomfort, with an Interim prosthesis that was almost always unstable because or a lack of good soft and hard tissue support. Nevertheless. 1t was believed that the final goal of reaching a fixed prosthesis after a E>- to 7month waiting period would make the patient's discomfort worthwhile. Pract1t1oners next doubted whether 11 was possible to place implants and a fixed pros· thesis 2 months after the extractions 1n a one-stage protocol. The more optimistic cl1n1c1ans thought that perhaps this could all be done in 1 day. The obiect of this book 1s to present the basic ideas about immediate implant loading (Ill) as of 2003. The fast pace of changes in the field of implant dentistry to reduce the walling times and thereby benefit patients requires us to be careful 1n using this new form

Fig 1-1 Panoramic rad1ograph showing fracture of !he two most distal mandibular implants. This forced the chnictan 10 readapt lhe prosthetic exlenS graph foll0W1ng eiate Loading or Single Implants

various authors (Aguirre 1996), making their use ideal for such situations. E-PTFE mem· branes that are reinforced with litanium are easier to manipulate and maintain the space better. Titanium tacks are required to affix them; the tacks are then removed along with the membrane when the pnmary goal has been achieved. The main disadvantage in

using these membranes 1s that they must not touch ad1acent teeth, because they could become contaminated upon removal. This 1s one reason why the full volume of desired osseous tissue cannot be regenerated (Fig 290). In these cases, the placement of a rree epithelial and g1ng1va1 graft (Figs 2-91 and 292) 1 month before membrane removal and

Fig 2-90 After careful curetung, tne alveolus IS filled with resorbable bovine hydroxyapahte (81o-Oss Spon91osa) and an e-PTFE membrane w11h titanium re1nforcemern !Gor&Texl 1s placed.

Fig 2·91 Five months later, a free soft tissue graft performed

44

is

Fig 2-92 Note the amount of kerahnized t1SSUe 1 month afler surgery. The les10n, however. is still presenL At this lime the membrane is removed and the implant Is placed

Implant Placement 1n the Alveolar Process with Width and/or Height Limitations

implant placement will enhance the final esthetic results. The free gingival graft contains a large number of collagen fibers, and suturing of the ging1va after crown cementalion will not result in g1ngival retraction (Figs 2-93 and 2-94 ). The waiting period for this regenerahve method before Ill can be performed 1s about 6 months.

Fig 2-93 A penap1cal rad109raph is obtained 10 verify the frt of the CemOne abutment before the prosthesis is fabncated Note that one of the membrane fixation screws has not yet been removed.

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Fig 2-94 Oelinmve s11ua1ion afle< placement of crown and veneers on adracen1 1ee1h. The use of a free graft allowed ror immediate crown placement. The lost vo~ ume has been regained. solving me es1het1c problem.

45

Chapter 2 • Surgical Technique for Immediate Loading of Single Implants

Sometimes 1t is possible to extract an 1m· pacted canine and immediately place an im· plant abutment and crown (Figs 2-95 lo 299). To make this a viable option. enough remaining bone must be left for primary stability or the implant (at least 10 mm). For this reason. the osteotomy performed must preserve as much bone as possible to surround the implant. The initial incision is made on the crest with a slight palatal displacement and should extend wrth1n the sulcus on both the buccal and the lingual. This will provide enough tissue for an ample flap to be raised. If necessary, the initial Incision can be ac·

companied by two vertical 1nc1s1ons to gain better access to the impacted tooth (Fig 295). Once the extraction 1s completed and before dnlltng preparations for lhe implant are begun. 11 should be decided whether enough bone is available to provide sufficient stability to withstand the forces that will be loaded on the implant. If there is any doubt, the implant must be left covered, or perhaps regenerative procedures should be performed. All bone that is removed should be collected in the bone fitter and used to fill possible voids. The implant that is placed should be long enough, and a 5-mm-Oiameter implant 1s sometimes needed. Once the implant 1s placed. the possible defects or voids are filled in wrth bone mixed with GFnch plasma. Placement of a resorbable membrane is optional.

Fig 2·95 Placement of a 20-mm-tong implant after the extractton of an impacted canine.

Fig 2·96 The implant mount shows the emergence profde of the lmplanl

Implant Placement Immediately After Extraction of an Impacted Tooth

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Implant Placement Immediately After Extraction of an Impacted Tooth

Fig 2-97 Panoramic rad1e> graph showing the pos11ion or the impacted canine and almost complete resorption or the root 01 the pnmary tooth.

Fig 2-98 Panoramic rad1cr graph of an 1mplan1 placed 6 months previously, prior to construction ol final restoration.

Fig 2-99 Two-year pOstoperalJve cl1rncal vtew.

47

Chapter 3 Prosthetic Features of Immediate Implant Loading in Single Teeth Vicente Jimenez-Lopez

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The poss1b11ity of 1mmed1ate implant loading (Ill) 1n single teelh obviates the need for a removable partial denture. Vanous circumstances can cause the loss of a natural tooth. A well preserved alveolus may be present; large block-like defects may be found apical to the tooth; or partial bone loss may be present which most frequently affects the buccal side. The tooth may still be 1n place or 1t may have been already extracted. • These various situations will give rise to d11ferent therapeuhc methods.

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Extracted Tooth and WellPreserved Alveolus, or Alveolus with Minimal Bone Loss These patients present with a slight g1ngival retracuon on the buccal stde; there 1s minimal bone loss. although the palatal aspect is usually better. The fact that the papillae are preserved results 1n a better prognosis (Fig 3·1). It is important to perform careful tooth extraction to preserve the alveolar tissue; rt 1s also important to curette the future implant

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Fig 3-1 of the g ngrva 2 mon1hS after ex· 1rae11on of 1he maxillary nghl l31cr.:11 1nc1sor.

49

Chapter 3 •

Prosthetic Features ol Immediate Implant Loading 1n S.ngle Teeth

Fig 3-2 An implant IS placed In tho aM!olar bed wh •rt several threads on thu buccat S>de are lelt un-

Fig 3-3 The bone defect .., m.;.1,u••'CI to calculate ai> proximately how much bone IS noodud for grafting

covur~d

Fig 3-4 A preiaoncm

r

1•rr ~n• ~- 3 years

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Figs 3-70 and 3-71 The same patient (left} oerore tron1mcnt and rnghtJ alter trea1meo1

67

Chapter 3 • Prosthetic Feat ures of Immediate Implant Loading in Single Teet h

Patient Age The patient's age 1s another factor to consider, because implants should never be placed 1n the anterior area until the patient has completed growth (Fig 3-72). As a general guideline. the minimum age is 17 to 18 years for women and 18 to 20 years for men. To obtain absolute certainty. radiographic studies of the wrist can be performed to determine the state of the growth cartilage (another option 1s to superimpose two lateral cranial radiographs, the second obtained 6 months after the first, to check for variations). II must be remembered that the anterior areas of the maxilla and mandible

mature sooner than the posterior. which takes longer to complete its vertical growth. Should an implant be placed during the developmental stage. the implant acts as an ankylosed tooth, stopping growth in that area. This will create a step-like defect. where the implant is left behind while the growth pattern moves the bone and natural dentition onward. In the n1andible. the opposite occurs. For this reason, the extraction of ankylosed teeth is also recommended to allow for further skeletal development (Figs 3-73 and 3-74). Once the growth cycle has run its course. the placement of an implant can then be considered.

Fig 3-72 False g1n9iva had 10 be used 1n lh1s patient. wllO rece1"'3d im-

plants at age 14. Now !he patient Is 27 years old, and !he right anterior segment and dent111on have descended due ro osseous growth.

68

Patient Age

Fig 3-73 An 1molant was placed 1n the maxillary left lateral 1nc1sor posrt1on 1n a 14-year-Old patient Because of developmental growth. me tooth remained high and out of occlusion compared to ttle adJacent teeth

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Fig 3-74 The problem was solved by a g1ngivec1omy, followed by substitution of this short crown wrth a longer one.

69

Chapter 4 Implant Surgery for Immediate Loading of Hybrid Prostheses in the Mandible Ricardo Fernandez Gonzalez

Since Branemark et al ( 1977) and Adell et al ( 1981) first pubhshed the results of treatment with fixed prostheses in the mandible in completely edentulous patients. many other studies have been published, providing evidence for the high success rate of these rehabilitations in the medium and long term (Jemt 1991. Naert et al 1992. Lindquist et al 1996). Nevertheless. this kind of treatment traditionally required a waiting period of 3 to 6 months from the time the process was begun unhl the patient received the implantsupported prostheslS and was able to regain adequate runction. During this interval. the patient had to undergo implant placement surgery. followed by a week of not being able to wear any type of prosthesis while the tissues healed. Once the sutures were removed. the patient was allowed to wear lhe prosthesis. although its stability and retention were limited due to remodeling of soft tissues. Once the implants had osseo1ntegrated, the patient had to undergo a second surgery to place the implant abutments. and the prosthesis had to be relined once more. All of these steps generated discomfort that affected patients' work and social lives and were not well tolerated by some of them.

If the implants and the abutmenrs are placed in a single stage, and a hrst impression taken at the same time, the palient can have a prosthesis placed In 6 to 96 hours. with the same features of the traditional implant-supported prosthesis. Nevertheless. the implant wlll be subject to loading, although 11 has not yet osseo1ntegrated. Current thought supports the idea that premature loading per se 1s not responsible ror fibrous encapsulation of the implant. Instead, fibrous encapsulation is linked to an excessive amount of m1cromoven1ent at the bone1mplant interface dunng the healing process (Brunski 1993, Szmukler-Moncler et al 1998). If an implant 1s placed and subiected to forces capable of producing macromovements. osseointegration will be hindered and connective tissue will develop between the implant and the bone {Branemark et al 1969. Brunski 1993). On the other hand, 1f these forces are minute, the osseointegrat1on process can be completed (Cameron et al 1973). The amplitude of movement that stalls osseointegration is estimated at 50 to 150 µm (Szmukler-Moncler et al 1998). However, if a sufficient number of implants are placed and splinted by a horseshoe-shaped alloy structure. even if significant forces are applied. the amount of m1cromovement 1n71

Chapter 4 • Implant Surgery for Immediate Loading of Hybrid Prostheses 1n the Mandible

duced will not exceed the limits that hinder osseointegrat1on. This is similar to the effect obtained when teeth with advanced periodontitis and mobility are splinted with a single-structure prosthesis. Ample movement of those tooth roots would be reduced drastically, to a clinically imperceptible level. even if the prosthesis sustained significant occlusal forces. When rehabilitating the mandible with a structure supported by a single-piece, horsesho~haped structure. the various forces loaded al the different planes would be compensated and would not induce macromovement during the healing phase. Current literature supports 1mmed1ate implant loading (Ill) in the mandible, although the success rate 1s somewhat inferior to that achieved with the tradrtional implant protocol (Schnitman et al 1990, Henry and Rosenberg 1994, Salama et al 1995. Chiapasco et al 1997, Schnitman et al 19g7, Tarnow et al 1997, Horiuchi et al 2000, Malo et al 2000, Ganeles et al 2001, Colom1na 2001, Jimenez-Lopez 2001: see chapter 1 ).

For this reason, the indications for this type of treatment must be limited to patients who have difficulty with a deferred protocol. In the authors' opinion, the s1tuat1ons that allow for Ill are the following: • Completely edentulous patients who cannot tolerate a removable prosthesis (soft tissue ulcers. lack of retention. Jack of adequate chewing ability) and wait 3 to 6 months for the definitive fixed prosthesis • Partially edentulous patients with insufficient bone to place implants at this level and with antenor teeth with a poor survival prognosis • Patients with one or more teeth in the mandible that must be extracted. while the remaining teeth have a poor prognosis (Figs 4-1 to 4-5) • Patients who are not edentulous but must undergo extractions; here. the extractions and implant placement are done in the same surgical stage. so the patient need not use a removable partial denture

•

Fig 4-1 Suay-e1ght·year-0ld patient with untrealed advanced chrome penodontrtJs.

72

Implant Surgery for Immediate Loading of Hybrid Prostheses in the Mandible

Fig 4-2 Penapocal series of the pahent showing substantial Joss of peoodontal support: canes. perr apCaled because of the nsi< ol CM!rheal•ng lhe bone dunng dnl ng

F"ig 4-11 TorMQr;

76

Treatment Planning ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

moclate patient hygiene care 1n the 1nterprox1mal spaces and benefn pen-implant tissue health. If there ts an increased risk of implant loss. the number of implants to be placed should be increased This wcry. If a failure should occur. additional surgery will be unneces-

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sary and the patient will be able to continue wearing the implant-supported prosthesis. It is advisable to use a surgical template or guide to mark the buccal placement of teeth. so as to facilrtate correct implant pos111oning and prosthesis fabrication (Fig 4·20).

Fig 4-f2 P"i ent wi1h flVll implants and an alloy rosm hybnd prosthesis placed 72 hows alW< .org.-ry. The •nchna1ion of the distal implants can be seen

rig 4-13 ~nesis ot lhe same pa:Jent. wl1ICh snows tr.. en « - e cA me dlS1al implant$ around the k!liGI ol Id b N felt secono Pnovabons).

Fig 4-18 The implant at the 1er1 second premolar site .s 1ncl1nf'd so as not to harm the mandibular nerve. If tn. mol:vn had not been Slightly l•ttod •1 would ha\le r&QIJlred a more mesial IJOS"llOnuig and the abutments ..wuld htM! been too close IOg(ltner. maiung hygiene dillcun and comc:"o""s"'g the heB 111 and Slabll.ly of pefSICle of the strUcture which IS lilOll placoo cr;er Ill"' model to ensure 1ha1 •tallows for tho c•'l ot tho replica

r(

100

e lh» a;.>a 10 be per1oraled IS marked t>egun. enabling wrnicahOn of mo good iq b tWi!en ll>B hole and the replica

Fixed Hybrid Prostheses

Fig 5-42 Once the gold cylinder 1s screwed onto the rep11ca. n can be venhed that the alloy structure allOws for its exrt through the hole.

Fig 5-43 The same process 1s followed for lhe r&

Fig 5-44 Mechanized orifices for lhe five implants.

Fig 5-45 Smoolh cylinders are screv;ed onio the five replicas In the model.

Fig 5-46 Supenor view of the interrela110nSh1p between the five cylinders and the structure.

Fig 5-47 Inferior vl- of the interrelahonsh1p between the hve cylinders and the structure.

ma1nmg cylinders.

101

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Chapter 5 • Immediate Implant Loading with Overdeniures and Mandibular Hybnd Prostheses

The next step 1s to weld the most anterior implant to the structure through the use of a laser (Figs 5-48 to 5-50). Only one implant is welded because no master cast is 100% exact compared to the intraoral situation. and even if the abutments are sphnted wrth acryilc or taken ind1v1dually. no exact model can be obtained The only technique avail· able today to achieve a precise master cast 1s the Rigid Impression Stent (RIS). which allows for metal nngs to be placed 1nd1v1dually

and splinted together with plaster (this system will be described later in this section). In 1992 Jimenez and Torroba published a method of obtaining passive tit of the gold cylinders to the structure by bonding them directly In the mouth using previously prepared exit holes in the metal structure. This method results in an absence of tension between the prosthesis and implants. Following these principles, II was thought that it would be a good idea to create a master cast from

Fig 5-48 The cy11nder Is placed on the mOdel on lhe most anterior Implant. and the alloy struC1ure IS placed.

Figs 549 and 5-50 Laser welding is performed on bolh sides 10 re1nf()(ce the stability of the structure

102

Fil(ed Hybrid Prostheses

a key that would permrt the placement of the gold cylinders onto the structure and, later, bonding directly in the mouth. To enhance retention. the cylinders should be sandblasted externally (Figs 5-51 and 5-52). Once the most anterior cylinder is welded. the other lour cylinders are screwllghlened to the Implants. Rubber dam is placed to isolate the wound, and the structure 1s placed over the cylinders; the most anterior. which is welded. is screw-tightened

to the implant. The next step 1s to venfy the correct fit and place an adhesive cement such as Panavia (Kuraray) around each or the four cylinders lo bond them to the structure. Since Panav1a is an anaerobic cement. it must be isolated with petroleum jelly or Oxyguard (included 1n the kit) to allow for its polymerization (Figs 5-53 to 5-58). Once the cement has set. the screws are loosened and the structure is retrieved with the cylinders bonded to 11, thus providing a passive

Fig 5-51 Note the d ifference between the surfaces before and afler sandblas11ng

Fig 5-52 The tour cylinders have had eiew; same s1tuat1on .:is on Fig

of the structure aftllf U>e

tDruP.S ha\/ll

5-88.

113

Chapter 5 • Immediate Implant Loading with Overdentures and Mandibular Hybrid Prostheses

Fig 5-90 Companson between the s.ze of lhe 1emPOrary proslhes.s and the dehnrt1ve one

Fig 5-91 The waxup 1s 1ned 1n lhe mouth

Fig 5-92 The waxup 1n maximum 1mercuspation.

Fig 5-93 S1hcone reglslralion ol cenlnC relation.

ticulator. taking care that occlusion exists at least to the first molar (Rg 5·90). The waxup is later tried 1n the mouth (Fig 5-91) and checked for esthetics and occlusion. A registration is taken in centric relation so that remounting procedures can be performed if necessary and a more precise reference can be obtained (Figs 5-92 and 593). The mandibular cast is remounted on the articulator. where any small discrepancies can be visualized and corrected (Figs 5-94 and 5-95 ).

As in the wax try.Jn (Fig 5-96). the esthetics leave much to be desired. since the tooth col· ors have multiple peculianties that must be duplicated In the final prosthesis (Figs 5-97 and 5-98). For this purpose, the prefabricated teeth will have to be adapted to the esthetic requirements and colors chosen. In these cases 1t is useful to employ the Poly· glass System. which permits variations 1n hue, shade, and chroma and changes in any necessary characterization to reach an acceptable final result (Figs 5-99 to 5-104 ).

114

Fixed Hybrid Prostheses

Figs 5-94 and 5-95 Final s1ruar1on or the case mounted on the articulator.

Fig 5-96 Antenor view of the prosthesis with the teeth waxed up

Fig 5-97 Observe the vanous tonal1bes or the remaining teeth

Fig 5-98 Final result of Iha mandibular prostheses. which is very similar to the natural teeth.

Fig 5-99 Each tooth must be characienzed by creat1n9 grooves and fissures to achieve characterization details from the Inside toward the surface.

115

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Chapter 5 • lmmeew ol tne alveoli wtn and wt,_\ mplants.

Fig 5-166 Aivooh after SUTur ng

Fig 5-167 The abutments are &Plir too w th res.n

133

Chapter 5 • Immediate Implant Loading wrth Overdentures and Mandibular Hybrid Prostheses ~~~~~~~~~

Fig 5-168 The duplicate of the new denture lS Checi5 Pohsh1ng.

Figs EM>6a and EM>6b The prosthesis IS ad1usted and polished and 1s ready to be fitted.

• Prosthesis placemen1 The new prosthesis is fixed with four screws, which are torqued to 45 N/cm (Fig 6-67a). The maxtllomandibular relationships and occlusion are checked and the necessary adjustments performed (Fig 6-67b).

164

The access holes are filled with temporary material or silicone. The patient can then be dismissed with the prosthesis placed in the mouth (Fig 6-68). After 7 days the sutures and the protective silicone can be removed.

Procedure

Figs 6-67a and 6-67b Tightening wrlh Torque Controller at 45 N/cm (Right) Occlusal ad1US1men1

Figs 6-68a and 6-68b Case completed 7 hours after Implant placement surgery.

•

Postoperative care The patients are given amoxicillin for 7 days and analgesics (acetaminophen) are prescribed. usually for 1 or 2 days to minimize postoperative discomfort. The patient is instructed lo apply ice to the chin and to rinse with saline solution alter every meal. During the first week, a liquid diet or easily chewed foods are recom-

mended. After 7 days. the patient should return to the ottice for the removal of the silicone sheet and sutures. At an appointment 3 to 4 weeks later, oral hygiene Is performed and radiographs are obtained. if they have not been already. The patient is then scheduled for a visit every 6 months, and annual control appointments are planned.

165

Chapter 6 • Branemarl< Novum: Surgical and Prosthetic Procedure ~~~~~~~~~~~~~

Patients Treated with Branemark Novum Case 1 A 47-year-old man with an implant-supported prosthesis over four implants and a bar in the maxilla (Fig 6-69 and 6- 70) suffered from advanced periodontal disease in the mandibular dentition. These were extracted and three implants were placed; the patient left the same day with a Branemark Novum prosthesis (Figs 6-71 to 6-73).

Fig 6-69

Fig 6-70

Fig 6-71

Fig 6-72

166

Fig 6-73

Patients Treated wrth Brlinemark Novum

Case 2 A 64-year-old woman with an unremarkable history had lost all her teeth 20 years prior and was treated with Branemark Novum (Figs 6·74 to 6-76).

Fig 6-74

• Fig 6-75

Fig 6-76

167

Chapter 6 • Branemark Novum: Surgical and Prosthetic Procedure

Case3 A 59-year-old man was completely edentulous in the maxilla and had penodontal disease in the six rema1n1ng teeth 1n the mandible. In the maxilla, eight implants were placed and the arch was rehabilitated wrth an AIHn-One structure (Nobel 810care). In the mandible, the remaining teeth were extracted and a prosthesis was placed over three Branemark Novum implants (Figs 6-77 and 6-78).

Fig S.77

Fig S.78

168

Pattents Treated wrth Branemark Novum

Case 4 An edentulous 43-year-old woman wrth an unremarkable history received Branemark Novum implants ror rehabilitation of her mandible (Figs 6-79 and 6-80).

Figs &-7g

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Fig 8-80

169

Chapter 6 • Branemark Novum: Surgical and Prosthetic Procedure

Case S A 77-year-old woman had various types of implants: a few were not osseointegrated and presented great bone loss (Fig 6-81 ). Her maxilla was rehabilitated with an anterosuperior fixed prosthesis of porcelain-fused-to-metal from first premolar (5 [14]) to first premolar (12 [24]). Her Kennedy Class I edentulous areas were treated with one implant on each side. In the mandible. she was treated with Branemark Novum (Fig 6-82).

Fig 6-81

Fig 6-82

170

Patients Treated with Brilnemark Novum

Case 6 This 57-year-old man had advanced periodontal disease 1n both arches (Fig 6-83). He was rehabilitated with a prosthesis over eight implants in the maxilla and the Br~nemark Novum System in the mandible (Fig 6-84).

Fig 6-83

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Fig 6-84

171

Chapter 6 • Branemark Novum: Surgical and Prosthetic Procedure

Case 7 A 51-year-old woman wrth advanced periodontal disease (Fig 6-85) was rehabilitated with a fixed prosthesis in the maxilla and Branemark Novum implants in the mandible (Fig 6-86).

Fig IHIS

Fig IHl6

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Acknowledgments

Conclusions 1. Branemark Novum constitutes a valid al· ternallve to treating the edentulous mandible quickly and simply tor prosthesis construction. 2. The surgical technique is slightly more complex and requires a good treatment plan. a solid evaluation of the clinical situa· tion. and significant experience in implant dentistry. 3. Although with this technique the percentage of failures 1s similar to that seen with the conventional technique, any lost implants must be replaced. 4. Although the majority of edentulous patients can be treated with Branemarl< Novum. mandibles with "D" quantity of bone (according to the Lekholm and Zarb index) must be managed carefully, while those in "E" are considered to be contraindicated for this procedure. 5. The Novum implants are available in two diameters (4.5 and 5 mm) and two lengths (11 .5 and 13.5 mm). The authors feel that the use of the 4.5-mm implants (as long as the cortical plate 1s engaged) permits the use of fewer drills (2.3 mm. 3.5 mm. and 3.8 mm) and thus confers a lower risk of

overheating. The 5-mm-diameter implants can be used as substitutes for the 4.5-rnm implants that do not osseo1ntegrate. Nevertheless. if the bone is wide and bicortical engagement 1s not possible with the 4.5-mm implants, the 5-mm implants must be used. 6. The Branemark Novum procedure takes less time using the prefabricated components. The lack of Impression taking, pouring, and fabrication of the structures allows for prosthetic rehabilitations of great precision.

Acknowledgments We would like to thank Professor P-1 Branemark and Barbro Svensson for supplying us with the instruments and components for our first few cases. To Dr Cosme Gay for his scientific support. To our anesthesiologists Ors Carlos Lopez Spicoloi and Agustin Prado Rubio. To the dental laboratory technicians Prodenta Canaria and Alejandro Diaz Falcon for their prosthetic work. To Lourdes Mesa Berriel for her excellent photography and Nobel Biocare for the use of illustrations included in this chapter.

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173

Chapter 7 Immediate Implant Loading in Patients with a Completely Edentulous Maxilla Paulo Malo Contributor: Marfa Dolores Zampieri

Recently a new concept has been employed with exciting results: immediate Implant loading (Ill) in the maxilla, with lhe aim of avoiding the standard healing period before the prosthesis 1s constructed and functional. Until relatively recently, Ill in the maxilla posed a serious risk of failure for patients. so 1t was not used. The nsk still remains high compared to the mandible. The failures. according to various· authors. do not exceed 5% to 20%. Co~sequently, Ill In the maxilla is used only in very favorable situations or when required by a patient, using a ratio of one implant per tooth and a completely sphnted prosthesis. The difference between the various studies regarding failure rates seems to depend on the patient selection criteria. For this reason, extraction of teeth and immediate placement and loading of im· plants, all in one appointment, are not recommended. In this area, 1t 1s important to be cautious. particularly 1n patient selection. clinical evaluatron. rad1olog1c evaluation, and treatment planning. as well as in applying the adequate surgical and prosthetic protocols.

The goal 1s to m1nim1ze the number of failures. It is also very important in this type of difficult and specific rehabilitation to establish good postsurgical maintenance, with the goal of maintaining primary anchorage and obtaining excellent load distribution for the implants to reduce tensions on the bone dur· ing the healing penod.

Patient Selection This is the key to any treatment plan with implants. There are certain requirements and contraindications that must be considered for patient selection, which are detailed as follows.

Requirements • The patient must be in good overall health, display meticulous oral hygiene, be motivated, and consider that Ill wrth a fixed prosthesis is an important functional and psychologic ractor. 175

Chapter 7 • Immediate Implant Loading in Pat1ents with a Completely Edentulous Max.ilia

• Patients who are completely edentulous must possess sufficient maxillary bone volume for the placement of at least six Implants. They should have sufficient bone height to place implants that are at least 10 mm long (Fig 7-1 ).

Contraindications The same criteria apply here as to the general populatton In implant treatment, but specific high-risk groups, characterized as follows, should be excluded:

• • • • • • •

Smokers Patients with uncontrolled diabetes Patients wrth 1mmunodefic1enc1es Emotionally unstable patients Patients under stress Unrealistic. demanding patients Noncomplianl patients (eg, those who show lack or hygiene, skip appointments. or do not comply with directions) • Patients with bruxism (Rg 7-2) • Patients with infection or general oral inflammation (Fig 7-3)

Fig 7-1 Panoramic rad1ograph showing good osseous llOlume in the maxillary sector.

Fig 7-2 Patient with bruxism.

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Fig 7-3 Patient wrth poor penodontal health.

Clln1cal Evaluahon

Figs 7-4 and 7-5 Since two teeth were able to be ma1nla1ned ror surgery. the surgical guide was able 10 use them 1or reference.

Fig 7-6 Extenslon of a fust molar In the shape of a premolar. The whole prosthesis is spltnted.

Clinical Evaluation The clinical evaluation 1s divided into three parts: • 1. Prosthetic evaluation 2. Esthel1c evaluation 3. Occlusal evaluation

Prosthetic evaluation The guidelines for an ideal prosthesis are detailed below. Occlusal forces on the axis of the implant In the rehabilrtation ot the maxilla. if one or more teeth remain. their extraction must be postponed until the implants are placed, be-

cause the surgical stent can use them for support (Figs 7-4 and 7-5). It is essential to have the surgical guide stent to ensure optimal implant placement. In extreme cases, computerized lomographic (CT) scans and computer-aided machining can be used for its construction. When implants require inclined placement. angulated abutments play an important role in guaranteeing the perfect emergence angle of the connecting screw. Alternatively. a prosthesis could be cemented to the abutments. Lack of cantilever Cantllevers should be avoided in the maxilla, but if they are necessary they should be as short as possible (Fig 7-6), since in most cases there is no esthetlc or functional 1ustification for their inclusion. 177

Chapter 7 • Immediate lmplan1 Loading 1n Patients with a Completely Edentulous Maxilla

To reduce occlusal pressure. the occlusal table of the postenor teeth should be narrowed. particularly the molar It must be considered that the more teeth there are in the extension. the higher the risk of failure. Consequently, extensions are contraindicated in brux1sts or 1n any patient with a history of breaking teeth or prostheses or present wear facets One implant per root in the edentulous maxilla When dealing with Ill. each tooth 1n the maxilla should be replaced with one implant. except for the lateral 1nc1sors (Fig 7-7) and the first premolar. when possible. because of the great d1ff1culty in ach1ev1ng good esthetics (especially the papilla). When no implant 1s placed in the lateral 1nc1sor region, lab techniques are simplified and better esthetics will likely be achieved in the anterior teeth. On occasion. the same rec-

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ommendat1on is apphcable to the first premolar when sufficient bone 1s available. Good relationship between the gingiva and the clinical crown When dealing with the replacement of one tooth. this goal is attainable. In large rehabilitations. however, rt 1s not always possible because a considerable amount of bone has been lost The use of osseous surgical procedures or artificial g1ng1va can prOVtde the prosthesis with excellent esthetic results. Naturally harmonious crown dimensions This can be achieved through adequate technical procedures. provision of art.ficial g1ngiva. or surgery to increase the osseous mass. Natural lip support In the edentulous patient labial support 1s determined in extreme cases by the prosthe-

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Fig 7-7 The highest ~Olo num00r ol implants •'v>uld b.. placed, while use ot tho ii.:ora• ll'ICISO< a•"3S should be a..ooeci to pr~ the g ng "31 pap.nae

178

Clinical Evalua11on

sis. whether it is fabricated of metal and acrylic or porcelain fused to metal. All definitive posterior prostheses should be porcelain fused to metal (see chapter 8) for the following reasons: • • • • • • • •

Enhanced esthetics Increased resistance to fracture Maintenance or the vertical dimension Similarity to enamel Better hygiene Improved endurance Easier patient adaptation Enhanced stain resistance

Despite all or these advantages, porcelain has several disadvantages: • It is difficult to manipulate and requires great skill. • It defonms the metal base. • It requires a large metal supporting base.

In major rehabilitations, this last inconvenience makes the structure heavy and difficult to work with. The use of titanium has made

these structures lighter (Fig 7-8). although other important inconveniences must be considered. Research is ongoing to solve these obstacles. Natural space for the tongue Fortunately, patients adapt remarkably well, so that after only a few days the patient overcomes phonetic problems. In extremely difh· cult cases. the structure might need remodeling, or the help of a speech therapist may be required. Perfect d istribution and spacing to preserve natural papillae In a large number of edentulous patients, the papillae do not regenerate. and surgery can recreate them. The best solution for those patients who have experienced a large loss of bone mass 1s artificial acrylic resin or porcelain ging1va (Fig 7-9). This field requires improvement, because few g1ng1val colors are currently available and there 1s a lack of pigment to provide a natural transrt1on from the tooth to the gingiva.

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Fig 7-8 Slructure ror maxillary rehab1htabon.

Fig 7·9 Porcetaon papillae on the anterior area.

179

Chapter 7 • Immediate Implant Loading 1n Patients with a Completely Edentulous Maxilla

Esthetic evaluation The esthetics of implant-supported prostheses become more important after the surgeon places the implants. Consequently, certain factors, such as emergence profile or incl1nat1on, n1ust be controlled from the out·

set by identifying the area to be rehabilitated and avoiding those situations where esthet· ics may be compromised. The following list enumerates the errors that may be made and their consequences and suggests solu· lions to provide an esthetically pleasing prosthesis.

POTENTIAL PROBLEMS AND ESTHETIC SOLUTIONS

Possible problems

Consequences/ solutions

1 Implants do not emerge through the central tooth axis. preventing papilla preservation

Generally not an acceptable situation. particularly in cases with high smile lines that show g1ngiva. The only solution is not to use certain implants or to remove them However, this may be acceptable when the prosthesis has a g1ng1val component incorporated or the patient has a low smile line.

2. Implants do not align properly with the m1dline

Same as above.

3. Implants are too angulated from the palatal to the buccal: thus the screw emerges on the labial aspect of the tooth

Can be solved with angulated abutments. The problem with these abutments hes in the possible lack of soft tissue, which might result 1n a v1s1ble metallic cervical ·root: In patients wtth a high lip line, the result 1s not saUsfactory. In some cases, artificial g1ng1va can be placed to hide this. Another alternative 1s Procera. but the crown will have to be cemented. This is the preferred solution and is explained 1n chapter 8. If the prosthesis 1s screw retained. the access hole can be covered with a porcelain inlay or with composites on the buccal.

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4. Implant emerges on the palatal aspect

180

This can be avoided by using angulated abutments. but the excessive width can lead lo speech difficulties and discomfort as well as the cantilever effect from the emergence profile to the inc1sal edge. This increases the risk of failure of both the restoration and the implant.

Clinical Evaluation

POTENTIAL PROBLEMS AND ESTHETIC SOLUTIONS

Possible problems

Consequences/solutions

5. Excess mes1odistal angulation of the implants

Connection and splinting of even the impression copings is drfficult or impossible, which may prevent the implant from being used. There are two solutions: do not use the implant, or try a customized abutment. Nonetheless, in the latter case. the prosthesis will not be screw retained, which presents other types of difficulties.

6. Implants are too close to each

The papillae cannot be regenerated and in some cases bone loss may occur. Lateral incisor implants should be avoided when implants have been placed in the adiacent area. In the maxillary incisors, one implant can be substrtuted for two teeth and two implants can be substituted for three or four adjacent teeth.

other

7. Implants are placed far to the buccal

8. High smile line that shows •

This can lead to dehiscence of the bone, dehiscence of soft Ltssue, loss of papillary volume. or darkening of the gingiva because of implant translucency. There will be an increased risk of implant loss The alternative is to use regenerative procedures with membranes or autologous bone grafting.

In esthetic terms. it is better to have fewer implants. In the edentulous maxilla. if 12 to 14 implants are planned, 8 to 10 implants should be placed with Ill so as to decrease the nsks. In these cases. in addition to being perfectly placed, the implants must follow the previously stated recommendations, such as having the same height of emergence profile so that the cervical junction of the clinical crowns of the esthetically relevant pieces maintain their harmony. In some cases, bone reduction will be necessary. with the risk of losing good bone support (a shorter implant will be required), or a bone graft may need to be placed to even out the residual crest.

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Chapter 7 • Immediate Implant Loading 1n Patients wnh a Completely Edenrulous Maxilla ~~~~~~~~~

POTENTIAL PROBLEMS AND ESTHETIC SOLUTIONS

Consequen ces/solutio ns

Possible problems 9. Implant has a d1Herent emer· gence profile compared to the ad1acent teeth

The implant may be higher or lower than the adjacent teeth. If 1t 1s higher, 1t can be hidden easily with a soft tissue graft displaced toward the coronal or with porcelain g1ng1va A grng1vectomy may be necessary on the adjacent dentition to even out the g1ng1val architecture. If the implant is lower. rt rS necessary to modify the bone and even 1t out before placing the 1mptant. In some cases, the s11uatron is not acceptable and the scr lut1on 1s difficult. In certain cases. the crown can be made to overlap the ridge, thus arttl1c1ally elongahng the clinical crown.

10. Implant 1s placed too tar toward the palatal due to lack of buccat cortical bone

In this situation. the 1n1t1al 1ncrs1on should be palatal to allow for apical repos11toning of the thick frap. thus 1ncreas1ng the buccat soft tissue bed. In extreme cases. the solution 1s an onlay bone graft.

Occlusal evaluation in completely edentulou s patients With regard to the occlusal evaluation. the same standards n1ent1oned 1n chapter 5 should generally be followed. Nevertheless. several pnnc1ples will be descnbed that are important to Ill 1n the maxilla. When a b1max1Uary rehab1litat1on is being conducted on an edentulous patient and Ill 1s desired 1n the maxilla. the problems of the maxilla must first be addressed. followed 3 months later by the mandible. because from a stallslical standpoint, an increased chance of failure exists when approaching both iaws at the same time. The maxilla. generally speaking. has a lesser loading capacity than the mandible and requires a longer healing period. Under these circum-

182

stances. 1t 1s recommend ed to use Ill while the implants in the mandible remain buried. This way. the chewing loads or pararunclional act1v1ty will be decreased However, as mentioned in chapter 5. because of functional features it is preferable to begin llL 1n the mandible and delay loading 1n the maxilla because the mandibular stab ty rs typ1cally worse. With regard to the occlusal design of the 1mmed1ate prov1s1onal prosthesis. the premolar and molar areas should have less contact than the anterior group. forcing the patient to apply more force with the anterior group. This is recommended not only because the area has more capacity to support such force with less nsk but also because patients have a tendency to brte with less force in the anterior sector.

Clinical Evaluation

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The cusps of molars and premolars should be kept as close as possible to zero degrees of angulation: this means making them as flat as possible to avoid deleterious off-axis forces. No contacts should exist be-

tween molars during protrusive. lateral, and parafunctional eccentnc movements, and premature contacts must not occur while the patient bites in centric relation ( Rgs 7-10 to 7·12).

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Figs 7-10 to 7-12 Conlrol of ocdus>0n 1n centnc telauon and eccen1nc Jaw move-

ments183

Chapter 7 • Immediate Implant Loading in Patients w1ih a Completely Edentulous Maxllta

Radiologic Evaluation Although 1n most cases a panoramic radiograph will suffice, a CT scan should be taken if there are doubts about the limits and quanltty of residual bone (Figs 7-13 and 7-14). In extreme cases. the use of a CT scan and computer-assisted manufacture is recommended to obtain an accurate model of the residual maxilla. The image can be obtained

1n the actual dimensions to enable the sur· geon to study and practice before the surgery: this also facilitates the construC11on of a surgical guide that adapts perfectly in the mouth and provides reference site points for implant placement. The SimPlant system (Materialise) is another alternative that can provide information on bone densrty.

Figs 7·13 and 7-14 Ewlualton wilh CT scans and panoramic radiograph

184

Treatment Planning

Treatment Planning The main factors that Influence success with Ill are: 1. Individual characteristics 2. Surgical technique 3. Prosthodonhc technique 4. Implant features 5. Protocol and postoperative maintenance 6. "Human error"

Individual characteristics Since characteristics vary greatly from one In· d1v1dual to another and can be responsible for the success or failure of implant therapy, the clinician must recognize and consider them during treatment planning to avoid undesirable results. The most important considerations are the 1mmunofog1c. osteogen1c, and healing capacities of the individual. since these can compromise the success or implants. In the same fashion. the presence of 1nsuHic1ent maxlflary osseous volume (Fig 7-15) as well

as low-density bone (Fig 7-16) can endanger primary anchorage of the implant.

Surgical technique During each phase of surgery, some mistakes may be made that soon provide unwanted results: • Incision: The wrong incision can cause necrosis or soft tissue or loss of rts volume. • Implant bed preparation: Excessive preparation or too frttfe Irrigation can produce bone necrosis. • Implant tightening force to the bone: II the strength is inferior to 30 N/cm good primary stability will not occur. On the other hand, if the force exceeds 60 N/cm'. bone necrosis may result. • Suturing: Overly tight suturing can result 1n soft tissue necrosis or loss of soft tissue volume. • Surgical hygiene: Performance of surgical procedures without proper aseptic technique can result 1n inflamma11on or infection .

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Fig 7-15 A 1aw taderoscrews will be placed 10 101n both structures.

Fig 8-105 Cast structure.

Fig 8-106 The worlucca1.

Figs 8-107 and 8-108 Buccal and ocdusal Views of both structures welded 10ge1her

245

Chapter 8 • l.aboe and lhe lal

er 11 lnUld be "' blad< (a!so tn !Bustrar.ons ll'llOUgl'I Fig 9-271

260

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Occlus al Adiust ment rn Compl ete Implan t-Supp orted Rehab rlrtauo ns

Ftg 9-20 Do gram OI tnc OOc1usa ad)US! ment in !he d