SINGLE TOOTH IMPLANTSSINGLE TOOTH IMPLANTS

Are the most demanding implant Are the most demanding implant restorations requiring extreme skill and restorations requiring extreme skill and proper planningproper planning

Are divided into:Are divided into:

-Anterior Single Implants-Anterior Single Implants

-Posterior Single Implants-Posterior Single Implants

Causes of single tooth lossCauses of single tooth loss AgenesisAgenesis TraumaTrauma Endodontic failureEndodontic failure FractureFracture ResorptionResorption CariesCaries

-maxillary central or lateral region is -maxillary central or lateral region is often the commonest site for tooth often the commonest site for tooth replacement in a restorative practicereplacement in a restorative practice

Why single tooth implants?Why single tooth implants?Options for replacing single tooth include:Options for replacing single tooth include:

-Removable partial Denture-Removable partial Denture

-Resin Bonded Prosthesis-Resin Bonded Prosthesis

-Space Maintainers-Space Maintainers

-Fixed Partial Denture-Fixed Partial Denture

However, single tooth implants has highest However, single tooth implants has highest survival rate with success ranging from survival rate with success ranging from 94.6-100% according to schmitt and Zaib 94.6-100% according to schmitt and Zaib 19931993

Advantages of single tooth implantsAdvantages of single tooth implants1)Adjacent teeth do not require splinted 1)Adjacent teeth do not require splinted

restorations:restorations:-Less risk of Caries-Less risk of Caries-Less risk of endodontics-Less risk of endodontics-Less risk of porcelain fracture-Less risk of porcelain fracture-Less risk of uncemented restorations-Less risk of uncemented restorations-Less risk of fracture of tooth-Less risk of fracture of tooth2) Psychological need of patient 2) Psychological need of patient

addressed. Patient does not desire two addressed. Patient does not desire two adjacent teeth-often virgin prepared and adjacent teeth-often virgin prepared and splinted to restore missing teethsplinted to restore missing teeth

Advantages contAdvantages cont….…. 3) Improved hygiene conditions 3) Improved hygiene conditions

-less decay risk-less decay risk-floss versus floss threader-floss versus floss threader-less pontic overhang-less pontic overhang

4) Decreased cold or sensitivity4) Decreased cold or sensitivitya) prepared teeth more temperature a) prepared teeth more temperature sensitivesensitiveb) Cement of tooth removed by tooth b) Cement of tooth removed by tooth preparation, toothbrush or scaler preparation, toothbrush or scaler sensitivitysensitivity

Advantages cont….Advantages cont…. 5) Improved esthetics5) Improved esthetics 6)Maintains bone in site 30% 6)Maintains bone in site 30%

decreasing width within 3 years after decreasing width within 3 years after extractionextraction

7) Decreases adjacent tooth loss -7) Decreases adjacent tooth loss -35% versus 0.05% risk at 10 years35% versus 0.05% risk at 10 years

Indications for single tooth implantsIndications for single tooth implants

MAINLY TOOTH LOSS OR MAINLY TOOTH LOSS OR ANTICIPATED LOSS FROM:ANTICIPATED LOSS FROM:

TraumaTrauma Endodontic failureEndodontic failure FractureFracture Root resorptionRoot resorption AnodontiaAnodontia

Missing lateral incisor-congenitaly Missing lateral incisor-congenitaly with radiographs showing less with radiographs showing less

interadicular spaceinteradicular space

Inadequate bucco-lingual width and Inadequate bucco-lingual width and its augmentationits augmentation

EXCESSIVE MESIODISTAL EXCESSIVE MESIODISTAL WIDTH WIDTH

Factors influencing Factors influencing treatment in single tooth treatment in single tooth implantsimplants--patient selectionpatient selection-smile line-smile line-cost-cost-biotype of the periodontium-biotype of the periodontium-patients age-patients age-Tooth shape-Tooth shape-Bone anatomy of the implant site-Bone anatomy of the implant site-position of the implant-position of the implant-Tooth position-Tooth position-Root position of the adjacent teeth-Root position of the adjacent teeth

Cont…Cont… Status of the adjacent teethStatus of the adjacent teeth Soft tissue profileSoft tissue profile High standard of prostheticsHigh standard of prosthetics Crown height and occlussal relationshipsCrown height and occlussal relationships Mesiodistal space at crown bone levelMesiodistal space at crown bone level

Generally the greatest problem is high Generally the greatest problem is high patient expectations, high esthetic patient expectations, high esthetic requirements and sensitive soft and hard requirements and sensitive soft and hard tissue managementtissue management

Missing central in an area with poor bone

Short crowns make bridge a poor choice—implants are best here

A large diastema makes fabrication of bridge a daunting task

AGE OF THE PATIENTAGE OF THE PATIENT Whereas it is important to place implant Whereas it is important to place implant

early before bone loss-it is critical to early before bone loss-it is critical to understand that growth and development understand that growth and development are affected by implant which acts as are affected by implant which acts as ankylosed teethankylosed teeth

Implants do not erupt along with adjacent Implants do not erupt along with adjacent teeth –hence many implants placed in teeth –hence many implants placed in adolescent with residual growth maybe adolescent with residual growth maybe infraposition after 10 years or the implant infraposition after 10 years or the implant may impede mesial shift resulting in may impede mesial shift resulting in assymetrical archassymetrical arch

Contin….Contin…. Ceasation for growth ranges from 11-15 years Ceasation for growth ranges from 11-15 years

and 11-17 years for boysand 11-17 years for boys Generally implants insertion in females should Generally implants insertion in females should

be done after 15 years and 18 years for males be done after 15 years and 18 years for males even then other factors indicative of growth even then other factors indicative of growth completion should be assesssed before completion should be assesssed before implant placementimplant placement

Secondly, endocrine changes must be assesedSecondly, endocrine changes must be assesed—menstruation in females and body hair and —menstruation in females and body hair and voice changes in menvoice changes in men

Size is also important –prospective implant Size is also important –prospective implant patient should have greater height than same patient should have greater height than same sex parentssex parents

Patient should not have grown over the last six Patient should not have grown over the last six months-one can use lateral ceph of two years months-one can use lateral ceph of two years with no changeswith no changes

Cont…Cont… Lateral incisor can be inserted at a Lateral incisor can be inserted at a

younger age than central incisor or younger age than central incisor or canine; it is less obvious to the eye canine; it is less obvious to the eye when lateral incisors are at a when lateral incisors are at a different position compared to the different position compared to the central incisorcentral incisor

It is also not unusual for the lateral to It is also not unusual for the lateral to be shorterbe shorter

Challenging estheticsChallenging esthetics The esthetics of a maxillary anterior The esthetics of a maxillary anterior

single crown a natural tooth is often one single crown a natural tooth is often one of the most difficult of the most difficult

The implant is often 5 mm or less in The implant is often 5 mm or less in diameter and round in cross section. A diameter and round in cross section. A natural maxillary anterior crown cervix natural maxillary anterior crown cervix region is 4.5 to 7.0 mm in mesiodistal region is 4.5 to 7.0 mm in mesiodistal cross section and is never completely cross section and is never completely round.round.

In fact the natural central incisor and In fact the natural central incisor and canine teeth are often larger in their canine teeth are often larger in their faciopalatal dimension at the CEJ than faciopalatal dimension at the CEJ than the mesiodistal dimension. the mesiodistal dimension.

CONT..CONT.. In addition, because the bone is lost first In addition, because the bone is lost first

in faciopalatal width, the greater width in faciopalatal width, the greater width implants in this dimension would require implants in this dimension would require even greats augmentation than even greats augmentation than presently advocated.presently advocated.

As a result the cervical esthetics of a As a result the cervical esthetics of a single-implant crown must single-implant crown must accommodate a round-diameter implant accommodate a round-diameter implant and balance hygiene and esthetic and balance hygiene and esthetic Parameters.Parameters.

Augmentation may be needed and a soft Augmentation may be needed and a soft tissue model is often required to transfer tissue model is often required to transfer the soft tissue clinical condition to the the soft tissue clinical condition to the laboratorylaboratory

Crown height spaceCrown height space The interocdusal space should be The interocdusal space should be

assessed carefully. Patients with Angle's assessed carefully. Patients with Angle's Class II Division II skeletal patterns, an Class II Division II skeletal patterns, an inadequate maxillomandibuiar inadequate maxillomandibuiar relationship, or a severe deficiency in the relationship, or a severe deficiency in the vertical dimension are contraindicated for vertical dimension are contraindicated for dental implants without prior corrections.dental implants without prior corrections.

Main problem is short implant abutment Main problem is short implant abutment that may not retain crownthat may not retain crown

Correct through orthognathic surgery, Correct through orthognathic surgery, orthodontic treatment or bothorthodontic treatment or both

MESIODISTAL SPACEMESIODISTAL SPACE An adequate mesiodistal space is necessary for An adequate mesiodistal space is necessary for

an esthetic outcome of an implant restoration an esthetic outcome of an implant restoration and the interproximal soft tissue of the adjacent and the interproximal soft tissue of the adjacent teeth.teeth.

A traditional two-piece implant should be at A traditional two-piece implant should be at least 1.5 mm from an adjacent tooth. When the least 1.5 mm from an adjacent tooth. When the implant is closer than this to an adjacent tooth, implant is closer than this to an adjacent tooth, any bone loss related to the microgap, the any bone loss related to the microgap, the biological width, or stress will cause the implant biological width, or stress will cause the implant and adjacent tooth to lose bone. This may and adjacent tooth to lose bone. This may compromise interproximal esthetics and compromise interproximal esthetics and sulcular health of the implant and natural tooth.sulcular health of the implant and natural tooth.

The smallest-diameter implant body offered by The smallest-diameter implant body offered by commercial companies is 3.2 mm with a commercial companies is 3.2 mm with a module of 3.5 or more. Therefore the module of 3.5 or more. Therefore the mesiodistai edentulous space for a two-piece mesiodistai edentulous space for a two-piece implant should be implant should be 6.5 6.5 mm or greater. mm or greater.

Cont…Cont… One piece implant may be fabricated in a One piece implant may be fabricated in a

2.5mm-3mm diameter to accommodate a 2.5mm-3mm diameter to accommodate a reduced mesiodistal dimensionreduced mesiodistal dimension

These implants design do not have a These implants design do not have a micro-gap and the vertical defect is micro-gap and the vertical defect is narrower than most two piece implants narrower than most two piece implants

Such implants can therefore be placed as Such implants can therefore be placed as close as 1mm from adjacent teeth and can close as 1mm from adjacent teeth and can accommodate a 5mm mesiodistal missing accommodate a 5mm mesiodistal missing space.space.

BONE HEIGHTBONE HEIGHT Available bone will influence soft tissue drape, Available bone will influence soft tissue drape,

implant size, implant position (angulation and implant size, implant position (angulation and depth) and final esthetic outcomedepth) and final esthetic outcome

Important is 1) adequate bone volume.Important is 1) adequate bone volume.

2)Position of osseus crest-ideal mid 2)Position of osseus crest-ideal mid creastal position of the edentolous site should creastal position of the edentolous site should be 2mm bellow the facial CEJ of the adjacent be 2mm bellow the facial CEJ of the adjacent teeth and the interproximal bone should be teeth and the interproximal bone should be scalloped 3mm more incisal than midcrestal scalloped 3mm more incisal than midcrestal position-to allow development of of good position-to allow development of of good interproximal soft tissue heightinterproximal soft tissue height

CONT…CONT… Bone and soft tissue changes after Bone and soft tissue changes after

maxillary anterior tooth loss are rather maxillary anterior tooth loss are rather rapid and of considerable consequence. rapid and of considerable consequence.

As a result, many maxillary anterior As a result, many maxillary anterior edentulous sites require at least some edentulous sites require at least some bone and/or soft tissue modification bone and/or soft tissue modification before, in conjunction with, or at implant before, in conjunction with, or at implant uncovery. uncovery.

Under ideal conditions, the implant body Under ideal conditions, the implant body should not be inserted until the bone and should not be inserted until the bone and soft tissue are within normal limitssoft tissue are within normal limits

Cont…Cont…The crestal height of bone is one of the more The crestal height of bone is one of the more

important considerations for an implant in the important considerations for an implant in the esthetic zone.esthetic zone.

Overall bone height in an apical direction is not Overall bone height in an apical direction is not a problem in the anterior regions, it is often a problem in the anterior regions, it is often deficient at the crest of the ridge and greatly deficient at the crest of the ridge and greatly affects the position of the implant in relation to affects the position of the implant in relation to the adjacent teeth and the related soft tissue the adjacent teeth and the related soft tissue configuration. configuration.

Bone grafting for height adjacent to a tooth is Bone grafting for height adjacent to a tooth is more difficult and less predictable than grafting more difficult and less predictable than grafting for width or in extraction sockets. for width or in extraction sockets.

Cont…Cont… It is a clinical challenge when a single-It is a clinical challenge when a single-

tooth site has inadequate bone height tooth site has inadequate bone height at the crest and the adjacent roots also at the crest and the adjacent roots also have lost bone, because it is not have lost bone, because it is not predictable to grow bone on predictable to grow bone on a a natural natural tooth root.tooth root.

Therefore growing bone height both in Therefore growing bone height both in the edentulous site and growing bone the edentulous site and growing bone on the roots of the adjacent teeth is not on the roots of the adjacent teeth is not predictable.predictable.

To grow crestal bone height on the To grow crestal bone height on the adjacent roots, in relation to the ideal adjacent roots, in relation to the ideal crest of the ridge, orthodontic extrusion crest of the ridge, orthodontic extrusion of the teeth may be considered. of the teeth may be considered.

However, in cases of significant crestal However, in cases of significant crestal bone height loss, endodontic therapy and bone height loss, endodontic therapy and a crown on the affected tooth is often a crown on the affected tooth is often indicated after treatment. indicated after treatment.

After the bone on the adjacent teeth is at After the bone on the adjacent teeth is at an ideal height, the edentulous- site may an ideal height, the edentulous- site may be augmented with increased success.be augmented with increased success.

Facio -palatal WidthFacio -palatal Width Single-tooth loss often result in the loss Single-tooth loss often result in the loss

of some or all of the facial bone in the of some or all of the facial bone in the region of the missing tooth .region of the missing tooth .

In addition, a 25% decrease in In addition, a 25% decrease in faciopalatal width occurs within the first faciopalatal width occurs within the first year of tooth loss and a 30% to 40% year of tooth loss and a 30% to 40% decrease within 3 years.decrease within 3 years.

As a result even an intact alveolus 6 to 8 As a result even an intact alveolus 6 to 8 mm wide is often adequate in width after mm wide is often adequate in width after 1 year for a root form implant in a central 1 year for a root form implant in a central incisor position. incisor position.

The bone width loss is primarily from the The bone width loss is primarily from the facial region, because the labial plate is facial region, because the labial plate is very thin compared with the palatal plate, very thin compared with the palatal plate, and facial undercuts are often found over and facial undercuts are often found over the roots of the teeththe roots of the teeth

Cont…Cont… Therefore the majority of edentulous Therefore the majority of edentulous

maxillary central incisor single-tooth maxillary central incisor single-tooth sites require bone grafting for ideal sites require bone grafting for ideal cervical esthetics and hvgiene.cervical esthetics and hvgiene.

The amount of available bone width The amount of available bone width (faciopalatal) should be at least 2.0 mm (faciopalatal) should be at least 2.0 mm greater than the implant diameter at greater than the implant diameter at implant insertion and ideally more 3 mm implant insertion and ideally more 3 mm greater in width; a 3.5mm implant greater in width; a 3.5mm implant requires least 5.5 mm of bone width.requires least 5.5 mm of bone width.

Bone augmentation on width is very Bone augmentation on width is very predictable and should be performed predictable and should be performed before implant placement but also at before implant placement but also at the time of implant insertion, especially the time of implant insertion, especially when no dehiscence of implant is visible. when no dehiscence of implant is visible.

Soft Tissue DrapeSoft Tissue Drape The position and architecture of The position and architecture of

the interdental" papillae are noted the interdental" papillae are noted before developing the implant before developing the implant treatment plan.treatment plan.

The soft tissue in the region of the The soft tissue in the region of the edentulous site should ideally have edentulous site should ideally have the same color and form as that of the same color and form as that of adjacent teeth.adjacent teeth.

When a tooth is lost, the When a tooth is lost, the interdental papillae are often interdental papillae are often depressed compared with their level depressed compared with their level between healthy adjacent teethbetween healthy adjacent teeth

Cont…Cont… The use of a soft tissue removable The use of a soft tissue removable

prosthesis often accelerates the prosthesis often accelerates the collapse of the soft tissue and its collapse of the soft tissue and its apical migration. apical migration.

Therefore once the tooth is Therefore once the tooth is extracted, inter-dental papillae are extracted, inter-dental papillae are rarely at the desired height and are rarely at the desired height and are most often apically depressed.most often apically depressed.

Soft tissue manipulation to restore Soft tissue manipulation to restore their proper contour is often their proper contour is often required in conjunction with implant required in conjunction with implant therapy. therapy.

Transitional ProsthesisTransitional Prosthesis The transitional restoration tor a The transitional restoration tor a

single-tooth implant is often a single-tooth implant is often a removable prosthesis, which lacks removable prosthesis, which lacks stability and retention (hence the stability and retention (hence the name flipper). name flipper).

Instead, it is strongly suggested that Instead, it is strongly suggested that a resin-bonded fixed restoration be a resin-bonded fixed restoration be fabricated to provide lmproved fabricated to provide lmproved function, especially when crestal function, especially when crestal bone regeneration ls performed. bone regeneration ls performed.

The device should be bonded to the The device should be bonded to the tooth region s below the centric tooth region s below the centric occlusal contacts of the teethocclusal contacts of the teeth

The soft tissue-borne transitional The soft tissue-borne transitional restoration enhances crestal bone restoration enhances crestal bone loss during the graft healing, may loss during the graft healing, may cause bone loss around the implant cause bone loss around the implant during Stage I healing or even during Stage I healing or even implant failure from early loading and implant failure from early loading and may depress the interdental papilla of may depress the interdental papilla of adjacent teethadjacent teeth

Other transitional devices include Other transitional devices include Essix appliance, cantilevered Essix appliance, cantilevered transitional PD with pontic over the transitional PD with pontic over the surgical site, or a cast clasp RPD with surgical site, or a cast clasp RPD with indirect rest seats to prevent rotationindirect rest seats to prevent rotation

IMPLANT CREST MODULEIMPLANT CREST MODULE The two most common complications of The two most common complications of

anterior single-tooth implant anterior single-tooth implant replacement are abutment screw replacement are abutment screw loosening and crestai bone loss. loosening and crestai bone loss.

The crestal bone loss causes an The crestal bone loss causes an increased risk of peri-implantitis or increased risk of peri-implantitis or shrinkage of the tissue and poor shrinkage of the tissue and poor cosmetic results.cosmetic results.

Both of these conditions are in part Both of these conditions are in part related to the implant crest module related to the implant crest module design design

An implant body with an antirotational An implant body with an antirotational feature should be used for the single-feature should be used for the single-tooth implant. tooth implant.

The greater the dimension of the The greater the dimension of the external or internal hex for external or internal hex for antirotational feature), the greater the antirotational feature), the greater the resistance to shear forces once the resistance to shear forces once the abutment is inserted, which corresponds abutment is inserted, which corresponds to a decrease in abutment screw to a decrease in abutment screw loosening. loosening.

Smooth metal on the crest module Smooth metal on the crest module increases the crestal bone loss of the increases the crestal bone loss of the biological width (once the implant is biological width (once the implant is uncovered) and transmits shear forces to uncovered) and transmits shear forces to the bone the bone

Therefore smooth metal collars on the Therefore smooth metal collars on the implant crest module should be limited to implant crest module should be limited to approximately 0.5mm.approximately 0.5mm.

Implant SizeImplant Size The first factor that influences the size of The first factor that influences the size of

an implant is the mesio-distal dimension an implant is the mesio-distal dimension of the missing tooth. The average mesio-of the missing tooth. The average mesio-distal dimension of a central incisor is 8.6 distal dimension of a central incisor is 8.6 mm for a male patient and 8.1 mm for a mm for a male patient and 8.1 mm for a female patient. female patient.

However, the implant body should However, the implant body should obviously not be as wide as the natural obviously not be as wide as the natural tooth or clinical crown. Otherwise, the tooth or clinical crown. Otherwise, the emergence contour and interdental emergence contour and interdental papillae region cannot be properly papillae region cannot be properly established.established.

The bone level on natural teeth is 2 mm The bone level on natural teeth is 2 mm below the CEJ, and the natural tooth below the CEJ, and the natural tooth dimensions is 5.5 mm for central dimensions is 5.5 mm for central incisors. incisors.

This dimensions most closely resemble This dimensions most closely resemble an ideal implant diameter to mimic the an ideal implant diameter to mimic the emergence profile of a natural tooth.emergence profile of a natural tooth.

However, this ideal diameter is usually However, this ideal diameter is usually too large to adequately restore the soft too large to adequately restore the soft drape of the missing anterior tooth.drape of the missing anterior tooth.

Cont…Cont… The second factor that determines The second factor that determines

implant diameter is the necessary implant diameter is the necessary distance from an adjacent tooth root.distance from an adjacent tooth root.

When the implant is closer than 1.5m When the implant is closer than 1.5m to adjacent tooth root, bone loss on the to adjacent tooth root, bone loss on the adjacent tooth root may occur. adjacent tooth root may occur.

The distance from the interseptal bone The distance from the interseptal bone to interproximal contact SHOULD be 5 to interproximal contact SHOULD be 5 mm or less,to allow papilla to mm or less,to allow papilla to completely fill the space.completely fill the space.

At 7 mm the risk of a compromise in the At 7 mm the risk of a compromise in the interproximal space is 75%. Therefore interproximal space is 75%. Therefore intraseptal bone height is relative to the intraseptal bone height is relative to the maintenanc of the interdental papilla maintenanc of the interdental papilla and should be preserved.and should be preserved.

InIn consequence, the implant should be consequence, the implant should be at least 1.5 at least 1.5 m m from the adjacent teeth from the adjacent teeth whenever possible, and the interseptal whenever possible, and the interseptal bone on the adjacent teeth should be bone on the adjacent teeth should be within 5 mm of the eventual within 5 mm of the eventual interproximal crown contact position.interproximal crown contact position.

In summary, two mesio-distal parameters In summary, two mesio-distal parameters determine the ideal implant size. The determine the ideal implant size. The ideal width of the single-tooth implant ideal width of the single-tooth implant should ideally correspond to the width of should ideally correspond to the width of the missing natural tooth 2mm below CEJthe missing natural tooth 2mm below CEJ

However, distance between the roots of However, distance between the roots of the adjacent teeth should also be the adjacent teeth should also be measured. The implant diameter plus 3 measured. The implant diameter plus 3 mm (1.5 mm on each side) should be mm (1.5 mm on each side) should be equal to or less than the distance equal to or less than the distance between the adjacent roots at the crest of between the adjacent roots at the crest of the ridge (which is 2 mm below the inter-the ridge (which is 2 mm below the inter-proximal CEJ).proximal CEJ).

The next dimension that determines the The next dimension that determines the width of an anterior implant is the width of an anterior implant is the faciopalatal dimension of bone faciopalatal dimension of bone

The ideal width of bone would allow at The ideal width of bone would allow at least 1.5 mm on the facial aspect of the least 1.5 mm on the facial aspect of the implant so that if a vertical defect forms implant so that if a vertical defect forms around the crest module, that defect around the crest module, that defect would not become horizontal and change would not become horizontal and change the cervical contour of the facial gingiva.the cervical contour of the facial gingiva.

Therefore the feciopalatai width of bone Therefore the feciopalatai width of bone at the crest for an anterior Implant at the crest for an anterior Implant should have at least 1.5 mm on the facial should have at least 1.5 mm on the facial plus dimension of the implant at the plus dimension of the implant at the crest module, plus 1mm on the palatal. crest module, plus 1mm on the palatal.

The dimension of the implant reflect the size The dimension of the implant reflect the size of the crest module, not the implant body of the crest module, not the implant body dimension for example, a 4.1-mm crest dimension for example, a 4.1-mm crest module (on a 3.75-mm |mmodule (on a 3.75-mm |mplant plant body) needs body) needs 7.1 mm of 7.1 mm of mesiodistal bone, amesiodistal bone, a 3.5 mm 3.5 mm crest module (on a 3.25-mm imolant bodv) crest module (on a 3.25-mm imolant bodv) should have 6.5 mm of bone. should have 6.5 mm of bone.

The natural intraroot distance of the two The natural intraroot distance of the two central incisors distance is approximately 2 central incisors distance is approximately 2 mm. However, the natural roots of the central mm. However, the natural roots of the central to lateral and lateral to canine are often less to lateral and lateral to canine are often less than 1.5 mm apart, and often only 0.5 mm than 1.5 mm apart, and often only 0.5 mm separates them. As a consequence, the ideal separates them. As a consequence, the ideal size of the single-tooth imolant is usually size of the single-tooth imolant is usually smaller smaller in diameter than the natural tooth in diameter than the natural tooth root. root.

Often, the implant ideal diameters used to Often, the implant ideal diameters used to replace the average-size tooth result in a 4.1- replace the average-size tooth result in a 4.1- 5.2-mm implant for a central incisor, a 3.0-to 5.2-mm implant for a central incisor, a 3.0-to 3.5-mm implant for a lateral incisor, and a 3.7- 3.5-mm implant for a lateral incisor, and a 3.7- to 4,2-mm implant for a canine.to 4,2-mm implant for a canine.

when in doubt, the clinician should use an when in doubt, the clinician should use an implant with a smaller diameter. implant with a smaller diameter.

As such, a 4-mm-diameter implant may often As such, a 4-mm-diameter implant may often be used in the central implant position for a be used in the central implant position for a single-tooth replacement.single-tooth replacement.

Likewise, a.3.0- to 3.5-mm implant is often Likewise, a.3.0- to 3.5-mm implant is often used for a lateral incisor single-tooth used for a lateral incisor single-tooth restoration. restoration.

Though generally larger-diameter implant will Though generally larger-diameter implant will decrease abutment screw loosening, crestal decrease abutment screw loosening, crestal bone loss, and risk of long-term implant body bone loss, and risk of long-term implant body failure.failure.

PATIENT EXAMINATIONPATIENT EXAMINATIONA) A) Extra-oral ExaminationExtra-oral Examination: : Examine the area of the dental arch Examine the area of the dental arch

and sorrounding gingiva that is and sorrounding gingiva that is displayed when patient smiles or displayed when patient smiles or laughs—liplaughs—lip line and smile lineline and smile line

B) B) Intra-oral ExaminationIntra-oral Examination -T-There should be no evidence of here should be no evidence of

bleeding and increased probing depthbleeding and increased probing depth- Do palpation and ridge mapping- Do palpation and ridge mapping Examine level of ridge crest or formExamine level of ridge crest or form- Examine position and form of frenum- Examine position and form of frenum

Hard tissuesHard tissues

Examine teeth on either side of the Examine teeth on either side of the abutment:abutment:

-Are they restored with a crown or -Are they restored with a crown or large fillings?large fillings?-Is there exposure of the root -Is there exposure of the root surface?surface?

-is the root crown ration favourable?-is the root crown ration favourable?

-is there any mobility-is there any mobility

-What is the alignment of the clinical -What is the alignment of the clinical crown?crown?

OCCLUSSIONOCCLUSSION Assess both in ICP and RCP which Assess both in ICP and RCP which

should be as close as possibleshould be as close as possible If there is any discrepancies eliminate If there is any discrepancies eliminate

any deflective contact before any deflective contact before planningplanning

Assess where the guidance is and Assess where the guidance is and avoid situation where the implant is avoid situation where the implant is the one providing guidancethe one providing guidance

Assess any para-functional habitsAssess any para-functional habits -provide at least 7mm between -provide at least 7mm between

implant head and opposing toothimplant head and opposing tooth

Specific testsSpecific tests

Radiographic assesmentsRadiographic assesments

-IOPA-IOPA

-OPG-OPG

-CT-CT

-CBCT-CBCT MOUNTED AND WAXED UP CASTSMOUNTED AND WAXED UP CASTS

DIAGNOSTIC CAST AND A GOOD DIAGNOSTIC CAST AND A GOOD WAX UPWAX UP

THIS WILL REVEAL SOFT TISSUE DEFECTS AS WELL

PATIENT’S AESTHETIC EXPECTATIONSPATIENT’S AESTHETIC EXPECTATIONS • Realistic expectations ?Realistic expectations ?• Needs to discuss potential outcomes Needs to discuss potential outcomes

Lip lineLip line

a)a) Low lip line-display a predominance of Low lip line-display a predominance of mandibular teeth or equal mix of mandibular teeth or equal mix of maxillary and mandibular teeth. Low maxillary and mandibular teeth. Low aesthetic risk as gingiva not seenaesthetic risk as gingiva not seen

B) medium lip line-display most of their anterior B) medium lip line-display most of their anterior maxillary teeth and only very little, if any , of maxillary teeth and only very little, if any , of supporting periodontal structures . Medium risk supporting periodontal structures . Medium risk

Appearance of teeth and gingival embrasures is Appearance of teeth and gingival embrasures is of importance.of importance.

c) high lipline – display entire maxillary c) high lipline – display entire maxillary anterior teeth and significant portion of anterior teeth and significant portion of supporting soft tissue. High aesthetic risk.supporting soft tissue. High aesthetic risk.

Display of gingival structures increases Display of gingival structures increases the relevance of tooth proportion and the relevance of tooth proportion and emergence profile emergence profile

GINGIVAL BIOTYPEGINGIVAL BIOTYPE A) Thick gingiva biotype-predominance of A) Thick gingiva biotype-predominance of

thick broad band of attached gingva thick broad band of attached gingva (>6mm), resistant to recession. Low risk (>6mm), resistant to recession. Low risk for single tooth replacement for single tooth replacement

Can mask subgingival metallic Can mask subgingival metallic components components

Favours long term stability of peri-implant Favours long term stability of peri-implant soft tissue soft tissue

However thick gingiva biotype prone to post-However thick gingiva biotype prone to post-surgical scarring subsequent to augmentation surgical scarring subsequent to augmentation procedures procedures

For multiple teeth replacement, thick gingiva For multiple teeth replacement, thick gingiva biotype can be both favorable and detrimental biotype can be both favorable and detrimental

Favorable because tissue stability predictable, Favorable because tissue stability predictable, however less chances of papillae developing.however less chances of papillae developing.

B) Thin gingival biotype-highly scalloped B) Thin gingival biotype-highly scalloped gingival architecture, reduced soft tissue gingival architecture, reduced soft tissue thickness. Width of keratinized gingiva thickness. Width of keratinized gingiva 3.5-5mm. High risk3.5-5mm. High risk

Then and friable nature of soft tissues is Then and friable nature of soft tissues is conducive to formation and maintenance conducive to formation and maintenance of papillae but risk of gingival recession. of papillae but risk of gingival recession. Adjacent teeth need to be periodontally Adjacent teeth need to be periodontally healthy and with sufficient bone-crest healthy and with sufficient bone-crest height to maintain papillaeheight to maintain papillae

SHAPE OF TOOTH CROWNSSHAPE OF TOOTH CROWNS Square teeth-with thick gingival biotype. Low Square teeth-with thick gingival biotype. Low

riskrisk Triangular teeth-with thin gingival biotype. High Triangular teeth-with thin gingival biotype. High

risk risk When assoc with localized periodontal defects When assoc with localized periodontal defects

and loss of interproximal papillae-implant crown and loss of interproximal papillae-implant crown restored is square shaped with large contact restored is square shaped with large contact areas-compromised aestheticsareas-compromised aesthetics

Infection at Implant SiteInfection at Implant Site

Local infections assoc with periodontal disease, Local infections assoc with periodontal disease, endo lesions can reduce quantity and quality of endo lesions can reduce quantity and quality of hard and soft tissue at implant sites and adjacent hard and soft tissue at implant sites and adjacent sites. Acute infection is a high risk, chronic sites. Acute infection is a high risk, chronic infections medium risk.infections medium risk.

Bone level at adjacent teethBone level at adjacent teethSupport for interproximal papilae is related to Support for interproximal papilae is related to the height of bone crests on adjacent teeth the height of bone crests on adjacent teeth Contact point to bone rest in relation to implant Contact point to bone rest in relation to implant papilla (Tarnow)papilla (Tarnow)

<4mm 100%<4mm 100%

5mm 88%5mm 88%

>6mm 59%>6mm 59%

Distance of 6mm or more from alveolar Distance of 6mm or more from alveolar crest to contact point reduces probability crest to contact point reduces probability of intact papilla.of intact papilla.

Restorative status of adjacent teeth Restorative status of adjacent teeth Adjacent teeth with subgingival Adjacent teeth with subgingival

restoration pose a threat as can cause restoration pose a threat as can cause recession subsequent to placement of recession subsequent to placement of implant.implant.

Width of edentulous spanWidth of edentulous span

Width of hard and soft tissue in Width of hard and soft tissue in edentulous edentulous

spacespace Horizontal bone deficit-need to consider Horizontal bone deficit-need to consider

augmentation procedure augmentation procedure Soft tissue deficits-need to consider soft Soft tissue deficits-need to consider soft

tissue grafting eg connective tissue grafttissue grafting eg connective tissue graft

Height of hard and soft tissue in Height of hard and soft tissue in edentulous edentulous

space space Vertical hard tissue deficiencies are difficult to correct Vertical hard tissue deficiencies are difficult to correct

and not predictable. High risk and not predictable. High risk Mostly regenerative procedures increase the width of Mostly regenerative procedures increase the width of

the implant sites but do not capture adequate height.the implant sites but do not capture adequate height. Vertically deficient sites usually assoc with adjacent Vertically deficient sites usually assoc with adjacent

periodontally involved teethperiodontally involved teeth

These sites cannot be enhanced without These sites cannot be enhanced without addressing the periodontal d/s itself addressing the periodontal d/s itself

Minimum for single tooth implants Minimum for single tooth implants in anterior regionin anterior region

Standard Implants(3.6-4.1)Standard Implants(3.6-4.1)——ideal for upper centrals,upper and ideal for upper centrals,upper and

lower canines and lower premolarslower canines and lower premolars-requires a mesiodistal space of about -requires a mesiodistal space of about

7mm and vertical height of 7mm7mm and vertical height of 7mm Narrow Implants(3.3 mm or less)Narrow Implants(3.3 mm or less)-U-Usually weak and provides smaller sually weak and provides smaller

area of contact between bone and area of contact between bone and implantsimplants

--needs 5mm between adjacent crowns needs 5mm between adjacent crowns and roots and 7mm vertical spaceand roots and 7mm vertical space

-suited for upper lateral incisors and -suited for upper lateral incisors and lower incisorslower incisors

Wide implantsWide implants

Maximize potential bone implant Maximize potential bone implant contact and enable primary stability contact and enable primary stability by engaging both buccal and lingual by engaging both buccal and lingual cortical platecortical plate

-needs 9mm mesiodistal space and -needs 9mm mesiodistal space and 7mm vertical space 7mm vertical space

Not ideal for single anterior implantsNot ideal for single anterior implants

BASIC RULESBASIC RULES

Use longest implant possibleUse longest implant possible Implant length to crown ration should Implant length to crown ration should

be greater than 1be greater than 1 Align implants with overlying crowns Align implants with overlying crowns

so that load is directed along the so that load is directed along the long axis of the implantlong axis of the implant

Do not use single implants to support Do not use single implants to support a cantilevera cantilever