chapter 13 Rosenstiel

Question 1

What are the three types of implants?

Answer 1

subperiosteal
transosteal
endosteal

Question 2

What are the two categories of endosteal implants?`

Answer 2

• Blade (platform) – wedge shape or rectangular cross section
• 2.5mm wide, 8-15mm deep, 15-30mm long
• one stage, but rates lower than root form currently.
• Submersible titanium blades now available success rate of 80% over 5 years
• Drawbacks
o Difficulty of preparing precision slots for blade placement in comparison with placing holes accurately for root-form implants
o the disastrously large circumferential area of the jaw that can be affected when a blade fails.
• Root form (cylindrical)
• 3 to 6mm diameter, 8-20mm long
• most made of titanium or titanium alloy w/ or w/o hydroxyapatite coating
• threaded or non-threaded
o threaded are straight or tapered
• today most are grit blasted or acid etched to roughen surface and increase area for bone contacts
• advantages
o adaptability to multiple implant site preparations
o comparatively low adverse consequences similar to those experiences when a tooth is lost.

Question 3

what are the 4 indications for dental implant treatment in the partially edentulous patient

Answer 3

• Inability to wear a removable partial or complete denture
• Need for a long-span fixed partial denture with questionable prognosis
• Unfavorable number and location of potential natural tooth abutments
• Single tooth loss that would necessitate preparation of minimally restored teeth for fixed prosthesis

Question 4

what is the list of 9 contraindications to implant placement?

Answer 4

• Acute illness (absolute contraindication)
• Terminal illness
• Pregnancy (absolute contraindication)
• Uncontrolled metabolic disease (absolute contraindication)
• Tumoricidal irradiation of the implant site (could be previous)
• Unrealistic patient expectation
• Improper patient motivation (such as oral hygiene)
• Lack of operator experience
• Inability to restore with a prosthesis

Question 5

what are diagnostic casts used for (3)?

Answer 5

o to study the remaining dentition,
o evaluate the resid- ual bone,
o and analyze maxillomandibular relationships.

Question 6

what are the requirements for thickness of bone for implant placement and spacing?

Answer 6

• Placed entirely within bone (required thicknesses below)
o 10mm vertical bone
o 6mm horizontal bone
o This allows for 1mm of bone on both lingually/facially
• Space between adjacent implants → 3.0mm

Question 7

• Specific limitations resulting from anatomic variations among different areas of the jaws also must be considered. These include (4):

Answer 7

o implant length,
o diameter,
o proximity to adjacent structures,
o and time required for integration.

Question 8

anatomical considerations for implant placement and measurements?

Answer 8

o 2.mm above superior aspect of inferior alveolar canal
o 5.0mm anterior to mental foramen
o 1.0mm from PDL of natural teeth
• Anterior maxilla
o 1.0mm of bone remaining between apex of implant and nasal vestibule
o Placed on either side of incisive foramen
• Posterior maxilla
o 1. Less dense bone (than posterior mandible) (larger marrow spaces) – 6 month min osseointegration time – one implant for every tooth being replaced is recommended
o 2. Mx sinus is close to edentulous ridge
• 1.0mm required between floor of sinus and implant
• Ant. Mandible
o Success with immediate loading of implants in the anterior mandible has been reported. This seems to be possible because the implants can have good initial stability.
o Most straightforward, best quality bone
o Placed THROUGH cancellous bone, apex engages cortical plate of inferior mandibular border →
o 5.0mm anterior to mental foramen (because inferior alveolar nerve courses as much as 3.0mm anterior to the mental foramen before turning posteriorly and superiorly to exit at the formane)
• Post. Mandible
o 2.0mm from apex to inferior alveolar foramen
o Usually shorter, don’t engage cortical bone inferiorly, need slightly more time to integrate.
o If ade- quate length is not present for even the shortest implant, nerve repositioning, onlay grafting, or a conventional nonimplant-supported prosthesis must be considered.
o if short implants (8 to 10 mm) are used, “overengineering” and placing more implants than usual to withstand the occlusal load is re- commended. Short implants are often necessary because of bone resorption, which thus increase the crown/implant ratio when the normal plane of occlusion is reestablished (Fig. 13-14).
o The width of the residual ridge must be carefully evaluated in the posterior mandible. Attachments of the mylohyoid muscle maintain it along the superior aspect of the ridge, and a deep (lingual) depression exists immediately below it. This area should be pal- pated at the time of evaluation and examined at the time of surgery.

Question 9

where should the superior surface of the implant be in regards to the emergence profile?

Answer 9

Ideally, the superior surface of the implant should be 2.5 to 3.0 mm directly inferior to the emergence position of the planned restoration, particularly when the restoration is to be located in the anterior esthetic zone (Fig. 13-16).
Superior surface of implant 2.0-3.0 mm inferior to emergence profile of planned restoration

Question 10

what are the objectives for using surgical templates (4)?

Answer 10

• Delineate embrasures
• Locate implant within restoration contour
• Align implants with long axis of completed restoration
• Identify level of CEJ or tooth emergence from soft tissue

Question 11

how is thermal injury to bone minimized (2)?

Answer 11

• using a low- speed, high-torque handpiece,

* copious irrigation

Question 12

what are the goals of surgical uncovering (3)?

Answer 12

• accurately attach the abutment to the implant,
• to preserve attached tissue,
• and to recontour tissue as necessary.

Question 13

what are the advantages of osseointegrated implants? (surgical 5, prosthetic 3)

Answer 13

• Surgical
o Documented success rate
o In-office procedure
o Adaptable to multiple intraoral locations
o Precise implant site preparation
o Reversibility in event of implant failure
• Prosthetic
o Multiple restoration options
o Versatility of second-stage components
• Angle correction
• Esthetics
• Crown contours
• Screw- or cement-retained options
o Retrievability in event of prosthodontic failure

Question 14

what’s the difference between the healing screw and healing abutment?

Answer 14

healing screw (cover screw) placed after stage 1 surgery, healing abutment (interim abutment) is placed after second stage surgery

Question 15

what’s the difference between a healing abutment and healing cap?

Answer 15

healing abutment is placed directly into the fixture (body), but a healing cap is placed over the abutment

Question 16

what does the choice of abutment size depend on (3)?

Answer 16

the ver- tical distance between the fixture base and opposing dentition,
o the existing sulcular depth,
o and the esthetic requirements in the area being restored.

Question 17

what are the 5 types of abutments?

Answer 17

o Standard – cylinder, screw retained
o Fixed – similar taper to a preparation, cement retained
o Angled – similar to fixed, it is just bent at the junction of abutment and body, to correct for esthetic/biomechanical reasons, cement/screw retained
o Tapered – very short, screw retained
o Nonsegmented or UCLA – restoration directly built on the implant body, it is screw retained

Question 18

• Single- tooth restorations supported by implants may be indicated in the following situations (4)…

Answer 18

o 1. An otherwise intact dentition.

o 2. A dentition with spaces that would be more diffi-cult to treat with conventional fixed prosthodontics.
o 3. Distally missing teeth when cantilevers or partial removable dental prostheses are not indicated.
o 4. A prosthesis that needs to closely mimic the missing natural tooth.


Question 19

what are the 5 requirements for single tooth implant crowns?

Answer 19

• 1. Esthetics.

• 2. Antirotation, to avoid prosthetic component loosening.

• 3. Simplicity, to minimize the amount of components used.
• 4. Accessibility, to maintain optimum oral health.
• 5. Variability, to allow the clinician to control the height, diameter, and angulation of the implant restoration.

Question 20

what are two common indications that occur a lot with implants?

Answer 20

• congenitally missing maxillary lateral incisors (Fig. 13-42)
• and teeth in which endodontic treatment was unsuccessful (Fig. 13-43).

Question 21

• Loose restoration retaining screw, check for… (5)

Answer 21

o	Excessive occlusal contacts not in the long axis of the implant body
o	Excessive cantilever contacts
o	Excessive lateral contacts
o	Excessive interproximal contacts
o	Inadequately tightened screws

Question 22

what are potential problems with connecting one implant tooth to a natural tooth (4)?

Answer 22

o (1) breakdown of the osseous integration,
o (2) cement failure on the natural abut- ment,
o (3) screw or abutment loosening, and
o (4) failure of the implant prosthetic component.

Question 23

multiple factors are associated with implant bone loss which are (11)…

Answer 23

o 1. Inappropriate size and shape of the implant.
o 
2. Inadequate number of implants or implant positioning.

o 3. Poor quality or inadequate amount of available bone.
o 4. Initial instability of the implant.

o 5. Compromised healing phase.

o 6. Inadequate fit of the prosthesis.

o 7. Improper design of the prosthesis (e.g.,excessive cantilever, poor access for hygiene).

o 8. Excessive occlusal forces.

o 9. Deficient fit of abutment components (e.g., gaps that allow bacterial colonization).

o 10. Inadequate oral hygiene.

o 11. Systemic influence (e.g., tobacco use, diabetes).

Question 24

For implant body, what are the significant factors for success?

Answer 24

o precise placement,
o atraumatic surgery,
o unloaded healing,
o and passive restoration

Question 25

what are the guidelines for occlusion on Implant supported dental prosthesis?

Answer 25

1. Direct forces in long axis of implant body
2. Minimize lateral forces on the implant
3. Place lateral forces when necessary as far anterior in the arch as possible.
4. When it is impossible to minimize or move lateral forces anteriorly, distribute them over as many teeth and implants as possible.