This seminar deals with implant-related complications that lead to implant failure.this also discus diagnostic criteria and preventive methods for an implant failure.

1. IMPLANT FAILURE & TREATMENT
DR. PARTHA SARATHI ADHYA
Final year PGT, Dept. of Prosthodontics and Crown & Bridge
Under the guidance of :-
Prof.(Dr.) Jayanta Bhattacharyya.(H.O.D)
Prof.(Dr.) Samiran Das.
Dr. Sayan Majumdar.
Prof.(Dr.) Soumitra Ghosh.
Dr. Preeti Goel.

2. CONTENTS
• INTRODUCTION
• SUCCESS CRITERIA FOR DENTAL IMPLANTS
• IMPLANT FAILURE CLASSIFICATION
• CLINICAL & RADIOGRAPHIC CONDITIONS.
• DIAGNOSIS
• RISK FACTORS
• MANAGEMENT OF AILING AND FAILING IMPLANTS
• THE TREATMENT OPTIONS FOR MANAGING IMPLANT FAILURE
• CONCLUSION

3. Intrduction
• Implant dentistry has gained popularity because of very high success
and survival rates. However, implant failure and related complications
also have been reported. Dental implants demonstrated peri-implant
inflammatory reactions which were associated with crestal bone loss
that may eventually lead to the loss of an implant. It has been shown
that the inflammation is more pronounced and the inflammatory
process goes deeper and faster around the dental implant than around
the adjacent natural tooth. Not only inflammation various factors like
faulty prosthesis, host factors are also related to implant related
complication.

4. SUCCESS CRITERIA FOR DENTAL IMPLANTS
Mckinney, Koth, And Steflik: Subjective Criteria -
 Subjective criteria
i. Adequate function.
ii. Absence of discomfort.
iii. Patient belief that esthetics, emotional, and psychological
attitude are improved.
(Koth DL, McKinney RV, Steflik DE, Davis QB. Clinical and statistical analyses of human clinical
trials with the single crystal aluminum oxide endosteal dental implant: Five-year results. Journal
of Prosthetic Dentistry. 1988 Aug 1;60(2):226-34.)

5.  Objective criteriave Criteria -
i. Good occlusal balance and vertical dimension.
ii. Bone loss no greater than one third of the vertical height of the implant,
absence of symptoms and functionally stable after 5 years.
iii. No gingival inflammation.
iv. Mobility of less than 1 mm buccolingually, mesiodistally, and vertically.
v. Absence of symptoms and infection associated with the dental implant.
vi. Absence of damage to adjacent tooth or teeth and their supporting
structures.
vii. Absence of parasthesia or violation of mandibular canal, maxillary sinus,
or floor of nasal passage.
viii. Healthy collagenous tissue without polymorphonuclear infiltration.

6.  Revised Criteria For Implant Success Alberktson, Zarb, Washington, And
Erickson –
 Individual unattached implant that is immobile when tested clinically.
 ii. Radiograph that does not demonstrate evidence of peri-implant
radiolucency.
 iii. Bone loss that is less than 0.2 mm annually after the implant's first year
of service.
 iv. Individual implant performance that is characterized by an absence of
persistent and/or irreversible signs and symptoms of pain, infections,
necropathies, paraesthesia, or violation of the mandibular canal.
In content of criteria mentioned, a success rate of 85% at the end of a 5-year
observation period and 80% at the end of 10-year observation as a minimum
criterion for success.
(Smith DE, Zarb GA. Criteria for success of osseointegrated endosseous implants. J Prosthet Dent 1998;62:567-
72)

7. HEALTH SCALE FOR DENTAL IMPLANTS
International Congress of Oral Implantologists, Pisa, Italy, Consensus Conference, 2007.
Implant Quality Scale
Group
Clinical Conditions
1 Success (optimum
health)
a) No pain or tenderness upon function
b) 0 mobility
c) 2 mm radiographic bone loss from initial surgery
d) No exudates history
2 Satisfactory survival a) No pain on function
b) 0 mobility
c) 2–4 mm radiographic bone loss
d) No exudates history
(Misch CE, Perel ML, Wang HL, et al. Implant success, survival, and failure: the International Congress of Oral
Implantologists (ICOI) Pisa Consensus Conference. Implant Dent 2008;17(1):5-15.)

8. 3 Compromised survival a) May have sensitivity on function
b) No mobility
c) Radiographic bone loss 4 mm (less than1/2 of
implant body)
d) Probing depth 7 mm
e) May have exudates history
4 Failure (clinical or
absolute failure)
Any of following:
a) Pain on function
b) Mobility
c) Radiographic bone loss 1/2 length of implant
d) Uncontrolled exudate
e) No longer in mouth

9. IMPLANT FAILURE CLASSIFICATION
• Marco Esposito, Jan Michael Hirsh, Ulf Lekholm et al have classified oral implant failures
1)Biological Failures:
Early or primary (Before loading)
Late or secondary (After loading)
2)Mechanical failures:
Fracture of implants, connecting screws, bridge framework, coatings etc
3)Iatrogenic Failures
Improper implant angulation and alignment, nerve
damage
4)Inadequate Patient adaptation
Phonetics, esthetics, psychological problems.
(Esposito M, Hirsch JM, Lekholm U, Thomsen P. Biological factors contributing to failures of osseointegrated
oral implants,(II). Etiopathogenesis. European journal of oral sciences. 1998 Jun;106(3):721-64.)

10. • According to Abdel Salam el Askary, Roland Meffert and terrence griffin
• 1) According to etiology :
• A)Failures because of host factors
o Medical status - Osteoporosis and other bone diseases; uncontrolled
diabetes.
o Habits - smoking, para-functional habits.
o Oral status - poor home care, juvenile, and rapidly progressive
periodontitis, irradiation therapy.

11. • B) Restorative problems
• Excessive cantilever, pier abutments, no passive fit, improper fit of the
abutment, improper prosthetic design, improper occlusal scheme, bending
moments, connecting implants to natural dentition, premature loading,
excessivetorquing.
• C) Surgical placement
• Off axis placement (severe angulation)
• Lack of initial stabilization
• Impaired healing and infection because of improper flap design or others.
• Overheating the bone and exerting too much pressure.
• Minimal space between implants
• Placing the implant in immature bone grafted sites.
• Placement of the implant in an infected socket or a pathologic lesion.
• Contamination of the implant body before insertion

12. • D) Implant selection
• Improper implant type in improper bone type.
• Length of the implant (too short, crown-implant ratio unfavourable)
• Diameter of the implant.
2) According to origin of infection –
• Peri-implantitis (infective process, bacterial origin)
• Retrograde peri-implantitis (traumatic occlusion origin, non-infective, forces off the
long axis, premature, or excessive loading).
3) According to timing of failure –
• Before stage II (after surgery)
• At stage II (With healing head and or abutment insertion)
• After restoration.

13. 4) According to condition of failure (clinical and radiographic status)
• Ailing implants
• Failing implants
• Failed implants
• Surviving implants
5) According to responsible personnel –
• Dentist (oral surgeon, prosthodontist, periodontist)
• Dental hygienist
• Laboratory technician
• Patient.

14. 6) According to failure mode -
• Lack of osseointegration (usually mobility)
• Unacceptable esthetics
• Functional problems
• Psychological problems.
7) According to supporting tissue type –
• Soft tissue problems (lack of keratinized tissues, inflammation, etc.)
• Bone loss (Radiographic changes, etc.)
• Both soft tissue and bone loss.

15. CLINICAL & RADIOGRAPHIC CONDITIONS
 Ailing Implant-
• The ailing implant expresses radiographic bone loss without inflammation.
A deep pocket around the implant is evident, with absence of bleeding.
 Failing implants-
• The failing implant presents with constant deterioration at follow up and
maintenance appointments. Inflammation is present and is evident by
signs of edema, redness, bleeding, and suppuration. The implants are
immobile, but radiographic bone loss is obvious.

16.  Failed implants-
• Failed implants are those with progressive bone loss with clinical mobility
and that are not functioning in the intended sense.
• Failed implants are encapsulated in fibrous capsule.
• A failed implant is one that is fractured, has been totally refractory to all
methods of treatment, or These implants must be removed immediately,
because progressive destruction of surrounding osseous tissues may
occur.

17.  Surviving implants
Surviving is a term described by Alberktson that applies to implants that are
still in function but have not been tested against success criteria.
 Cluster failures of dental implants
 multiple implant failures occur in a patient; this is referred to as a “cluster
effect.
 Cluster failures usually occur soon after implant placement.
 Genetic or systemic factors ( Peget’s disease,Osteoporosis,Auto-immune
disorder) that influence the incidence of cluster failures.
 Ekfeldt and colleagues suggested that particular issues need to be
considered to prevent cluster implant losses (such as lack of bone support,
heavy smoking habits and bruxism)
(Ekfeldt A, Christiansson U, Eriksson T, et al. A retrospective analysis of factors associated with
multiple implant failures in maxillae. Clin Oral Implants Res 2001;12(5):462-467.)

18.  Bleeding on probing
 There is no correlation between BOP and histologic, microbiologic, or
radiographic changes around implants.
 Along with BOP modified gingival index can be used to assess marginal
mucosal conditions around oral implants
)Apse P, Zarb GA, Schmitt A, Lewis DW. The longitudinal effectiveness of osseointegrated dental implants. The Toronto study: Periimplant
mucosal response. Int J Periodontics Restorative Dent 1991;11:95–111)
DIAGNOSIS

19.  Probing depth and loss of attachment
• Probing should be done in normal probing force .2N- .3N.Probing depth
penetration around teeth has been found to be < 3 mm as opposed to 2 mm to 4
mm around implants.
• The so-called platform switch (abutment is located horizontally between implant
and crown) can complicate probing and, thus, hide the true extension of peri-
implantitis
 Pus formation
• Pus formation is always a sign of infection with active tissue destructive processes
taking place.
• Periimplantitis lesions usually yield some pus formation upon provocation by
pressing on the mucosal tissues, while mucositis lesions may not. Hence, pus
formation represents a specific diagnostic sign for the presence of peri-implantitis.

20.  Radiographic evaluation
 The distance from the implant shoulder to the alveolar bone crest
represents a reliable radiographic parameter for long-term monitoring in
clinical practice.
 A mean bone loss of 1.6 mm for the first year and a mean of 0.13 mm in
subsequent years.
 periapical with standard paralleling (PSP,) can be used to detect implant
abutment misfit and framework misfit.

21.  Radiographic features of failed implants-
o There can be two well-distinct radiographic pictures: a thin peri-fixtural
radiolucency surrounding the entire implant, suggesting the absence of a
direct bone-implant contact and possibly a loss of stability, and an
increased marginal bone loss.(>7 mm).
o When an implant fails because of a reason other than infection (such as
surgical or prosthetic trauma), it usually has mobility and peri-implant
radiolucency, and there may be an absence of inflammation.
o Failure due to an infection may manifest as progressive bone loss, a peri-
implant radiolucency, overt clinical signs of inflammation.

22.  Pain or sensitivity
• Pain or discomfort is often associated with mobility and could be one of the
first signs which indicate an implant failure.
 Dull sound at percussion
• It has been suggested that a subdued sound upon percussion against the
implant carrier is indicative of soft tissue encapsulation, whereas a clear
crystallization sound indicates successful osseointegration.
 Mobility-
o Clinically discernible mobility can be present without distinct radiographic bone
changes. Therefore, mobility is the cardinal sign of implant failure.
• Several different types of mobility can be seen
• Rotation mobility, Lateral or horizontal mobility, Axial or vertical mobility.
• it is recommended to remove the prosthetic construction and cheek the
implants for stability. Clinically discernible mobility after bridge removal can
confirm the presumptive radiographic diagnosis of implant failure.

23.  Assessment of implant stability-
o Reverse torque test-
 Implants that rotate under the applied torque are considered failures and
are then removed.
o Periotest-
 It is a device which is an electrically driven and electronically monitored
tapping head that percusses the implant a total of 16 times. The entire
measuring procedure takes about 4 s.

24. Esthetic evaluation
Mesiodistal dimension of
the crown
5-point rating scale
grossly undercontoured, slightly undercontoured, no
deviation, slightly overcontoured, grossly overcontoured
Position of the incisal edge
of the crown
5-point rating scale grossly
undercontoured, slightly undercontoured, no deviation,
slightly overcontoured, grossly overcontoured
Implant crown esthetic index was developed by Henry JA et alas an objective
tool in rating esthetics of implant-supported single crowns and adjacent soft tissues.

25. Labial convexity of the
crown
5-point rating scale grossly undercontoured, slightly
undercontoured, no deviation, slightly
overcontoured, grossly overcontoured
Color and translucency of
the crown
3-point rating scale gross mismatch, slight mismatch,
no mismatch
Surface of the crown 3-point ratingscale deviation of 1.5 mm or more,
deviation less than 1.5 mm, no deviation
Position of mucosa in the
approximal embrasures
3-point rating scale deviation of 1.5 mm or
more, deviation less than 1.5 mm, no deviation)
Contour of the labial
surface of the mucosa
5-point rating scale grossly undercontoured, slightly
undercontoured, no deviation, slightly
overcontoured, grossly overcontoured)

26. Color and surface of the labial
mucosa color (redness) and
surface characteristics
3-point rating scale (gross mismatch, slight
mismatch, no mismatch

27. RISK FACTORS
 Host factors-
 Systemic diseases-
• Osteoporosis, osteomalacia, fibrous dysplasia, diabetes mellitus, thyroid
disorders responsible for poor wound healing and poor osseintegration
which causes early failure of implants.

28. • HABITS
 Smoking:
 Significance
•Causes alveolar vasoconstriction and decreased blood flow
•Impaired wound healing due to compromised polymorphonuclear leucocytes
function, increased platelet adhesiveness as well as vasoconstriction caused by
nicotine.
 In case of poor oral hygiene, smokers have 3 times more marginal bone loss
Recommendations:
• 1.Obtain a smoking history
• 2.Advice on risks of periodontal breakdown
• 3.Advice on the prognosis .Smoking cessation

29.  Parafunctional habits-
• Most common cause of implant bone loss or lack of rigid fixation
• during the first year after implant insertion. Commonly manifests as
connecting screw loosening because of overload.
• Fracture of porcelain , progressive bone lose can also be seen
• Failures are higher in maxilla because of decrease in bone density.

30. • Increased number of implants to be placed
• Avoid cantilevers and occlusal contacts in lateral excursions
• Use of wide diameter implant to provide greater surface area. Progressive
bone loading and prosthetic design that improves the distribution of
stresses throughout the implant system.
• The anterior teeth may be modified to recreate the proper incisal
guidance and posterior interference during excursion.
• For maxillary implant restoration hollow night guard is used and in case of
mandibular implant supported prosthesis the occluding surface of
maxillary night guard are relieved over the implant crown.

31.  Quality & quantity presentation-
• Patients with low quantity and low density of bone were at highest risk for
implant loss.
• In type IV bone due to its thin cortex, poor medullary strength, and low
trabecular density implant failure is more.
• In division C & D bone chances of failure of implants is more due to less
bone support.

32. • Osteoplasty (C–w)
• Root form implants (C–h)
• Subperiosteal implant (C–h, C–a
partial, or completely edentulous
mandible).
• Disk design implants (posterior
mandible, anterior maxilla)
• Ramus frame implant (C–h
completely edentulous mandible)
• Autogenous iliac crest bone grafts to
improve the anterior division D are
strongly recommended.
• Endosteal implants of adequate height
can rarely be positioned in the
posterior maxilla with division D bone
without a sinus graft. After 6 months
post sinus graft, the division D
posterior maxilla is restored to division
A or C–h, and root form implants may
be inserted for posterior prosthodontic
support.

33. Malpositioning of Implants
 Classification
• Proximity of implants to each other
• Proximity of implants to adjacent
teeth
• Abnormal angulation of the implant
• Malposition of implant in relation to
position of the missing tooth it
replaces
 C/F & Diagnosis-
• Fracture of prosthesis.
• Fracture of abutment &
abutment screw.
• Bone loss.
• Peri-implantatis.
• Implant mobility.
 IOPAR
 CBCT

34. • Mechanical debridement of the affected implant should be done followed
by antiseptic treatment.
• Bone grafting is necessary to provide the added bone support.
• Implant abutment can be replaced by angled abutment and custom made
abutment.
• If it is determined that the implant cannot be functionally or esthetically
restored in its existing location, the implant can be left unexposed
beneath the soft tissue and not uncovered, or it can be uncovered but not
placed into function.

35. Improper occlusal scheme
 Articulating paper is used (30 μm) for the initial
implant occlusion adjustment in centric
occlusion under light tapping forces. The
implant prosthesis should barely make contact,
and the surrounding teeth in the arch should
exhibit greater initial contact.
 Any mobile teeth opposite to the implant
prosthesis should be extracted
 Fixed arch Prosthesis-Group function occlusion
or mutually protected occlusion with shallow
anterior guidance when opposing natural
dentition & No working and balancing contact
on cantilever.
 For the occlusion on overdentures, it has been
suggested to use bilateral balanced occlusion &
monoplane occlusion in resorbed ridge can be
used.
 C/F & Diagnosis-
• Bone loss.
• Screw loosening, screw
fracture.
• Fracture of the prosthesis.

36. • Such cases are treated by removal of prosthesis followed by regenerative
procedure and fabrication of new prosthesis.
• Reduction in cusp inclination can decrease the resultant bending moment
with a lever-arm reduction and improvement of the axial loading force.
Reduced cusp inclination, shallow occlusal anatomy, and wide grooves and
fossae may be beneficial when constructing implanted prostheses.
• Typically, a 30%-40% reduction in the occlusal table in a molar region has
been suggested because any dimension larger than the implant diameter
can cause cantilever effects.
• Cusp inclination has been found to produce a high level of For every 10°
increase in cusp inclination, there is an approximately 30% increase in
torque.

37. Improper cantilever
 Cantilevers are class-1 levers, which increase the amount of stress on
implants.
 According to Glantz ; D = F x L / E x W x H ,, D is the amount of
deformation, F is the force of occlusion, L, W, and H are the length, width,
and height of the cantilever, respectively, and E is the modulus of elasticity
of the material .
 The length of the cantilever should be minimized while maximizing the
height and width of the cantilever.
 Cantilever length is influenced by type of arch, no of implants , A-P spread,
type of prostheses to be used.

38. • At each increment of 5 mm in cantilever length, stress increased by
approximately 30% to 37% on the cortical bone around implant.
• According to McAlarney and Stavropoulos ratio of cantilever length and
A- P spread should be between 2-1.5.
(McAlarney ME, Stavropoulos DN: Determination of cantilever length anterior-posterior spread
assuming failure criteria to be the compromise of the prosthesis retaining screw-prosthesis joint.
Int J Oral Maxillofac Implants 1996;11:331-319)
• English recommended cantilever lengths be 1.5 times the A/P spread, but
shorter in poor quality bone.
(English C: Critical A-P spread. Implant Soc 1990;1:2-3)

39.  C/F & Diagnosis-
• Progressive bone lose.
• Fracture of the framework.
• Prosthesis Fracture.
• Screw loosening.
• Fracture of implant abutment
junction.
After regenerative treatment in ailing/ failing implants additional
implants can be placed to reduce to cantilever length.

40.  C/F-
• Torque loss.
• Progressive bone loss due to
inflammation.
• Peri-implantaitis.
• Screw loosening.
• Regenerative treatment should be done to
reduce the inflammation & to increase to bone
level.
• Use proper abutment with platform-switching
concept.
• CAD/CAM abutment can be used .
Implant Abutment misfit

41. Surgical Error
Excessive Pressure Heat generation Oversized osteotomy
Bone cell damage
The critical
temperature above
which bone necrosis
occurs is 47°C for 1
minute.
Lack of initial stability.
Mobility of implant
No regeneration of the peri-implant bone.
Presence of an inflammatory infiltrate in the gap between bone and implant
No .organization of the peri-implant bone clot

42. • Speed must not be above 1200 RPM.
• Proper coolant should be used while perform osteotomy.
• In case of over sized osteotomy larger diameter implant can be used &
loading can be delayed
Injury to the vital structures
Injury of inferior
alveolar nerve
Maxillary sinus
perforation
soft tissue injury
Paresthesia of lip
Nasal bleeding
Maxillary sinusitis
Flap dehiscence.
Presence of large edema
or hematomas.
Exposure of implant site.

43. • Proper flap design to prevent soft tissue injury .
• Large dehiscence can be treated by removal of granulation tissue and
resuturing.
• if sinus perforation occurs loading should be delayed by 6 months.
• Transantral endoscopic surgery can be done in case of maxillary sinusitis
or losing implant in maxillary sinus.
• Detailed initial treatment planning and careful surgery to unroof the canal
and move the neurovascular bundle inferiorly prior to fixture installation
can be done to prevent inferior alveolar nerve injury.

44. MANAGEMENT OF AILING AND FAILING IMPLANTS
• Identification of the cause.
 Peri-implantaitis
• Prophylactic procedures
• The patient should be motivated to perform an adequate level of
plaque control on a regular basis.
• Overcontoured and sub-gingivally placed prosthesis, particularly in the
proximal region, will prevent the patient from attaining optimal oral
hygiene, thereby jeopardizing the health of abutment teeth and their
surrounding tissues.

45.  Therapeutic strategies
• Cumulative interceptive supportive therapy (CIST)
• This protocol is cumulative in nature and includes four steps which should
not be used as single procedures, but rather as a sequence of therapeutic
procedures with increasing antibacterial potential, depending on the
severity and extent of the lesion.
• In 2004 it was modified and called AKUT-concept by Lang et al.
(Smeets R, Henningsen A, Jung O, Heiland M, Hammächer C, Stein JM, et al. Definition, etiology, prevention
and treatment of peri-implantitis – A review. Head Face Med 2014;10:34)

46. (Lang NP, Lindhe J. Maintenance of the implant patient. In: Lang NP, Lindhe J, eds. Clinical periodontology and
implant dentistry. Vol. 2: Clinical concepts, 5th edn. Oxford: WileyBlackwell, 2008: Chapter 60.)

47. A. Mechanical debridement (supportive therapy protocol A)
• Oral implants with evident plaque or calculus deposits adjacent to only
slightly inflamed peri-implant tissues), but lacking suppuration and having
a probing depth not exceeding 3 mm.
• While calculus may be chipped off using carbon-fiber curettes, plastic hand
instruments or ultrasonic instruments with a plastic tip.
• The use of a high pressure air powder abrasive (mixture of sodium
bicarbonate and sterile water), has been advocated, as this removes the
microbial deposits, does not alter the surface topography and has no
adverse effect on cell adhesion.

48. • CO2, Diode-, Er:YAG- and Er,Cr:YSGG- lasers are used in the treatment of
peri-implant diseases with increasing frequency
• Most of these lasers, function through vaporization mode. High
temperatures could alter or damage the implant surface making them
inappropriate for use in treating the implant defect. They could also result
in charring or coagulation of tissue, delaying the reparative cascade.
• The Er, Cr: YSGG laser, operating at 2780 nm, blates tissue by a
hydrokinetic process that prevents temperature rise.
(El-Askary AS, Meffert RM, Griffin T. Why do implants fail? Part II. Implant Dentistry. 1999; 8:265–
276.)

49. B. Antiseptic treatment (supportive therapy protocol B)
• The type of implant surface will determine the method of
decontamination.
1. critic acid (40% concentration; pH 1)
2. chlorhexidine gluconate (.1%)
3. Stannous fluoride
4. tetracycline
• contact with a supersaturated solution of are antimicrobials and/or
antibiotics, for 30-60 seconds have been used for the preparation of the
implant surfaces, as they have the highest potential for the removal of
endotoxins from both the hydroxyapatite and the titanium implant
surfaces.
• In general, 3–4 weeks of regular administration are necessary to achieve
positive treatment results.

50. • Machined titanium surfaces are the easiest to decontaminate and that
topical tetratcyclines.
• Tetracycline stimulates fibroblast growth in the affected area.
(Buser D, Merickske-Stern R, Dula K, et al. Clinical experience with one-stage, non-submerged
dental implants. Advances Dental Res. 1999; 13:153–161.)
• Prolonged application time of citric acid solution are not recommended for
use on HA surfaces, since this would alter the quality and impair its ability
to bond to the titanium body of the implant.
• If the HA is already damaged due to the virulence of the infection
surrounding the implant. It is eliminated completely by drilling and then
proceed to apply air abrasion or ultrasound and subsequently
decontaminate the area with.

51. C.Antibiotic treatment (supportive therapy protocol C)
• Before starting the antibiotic treatment the mechanical (A) and the
antiseptic (B) treatment protocols have to be applied.
• During the last 10 days of of the antiseptic treatment antibiotic treatment
should be used.
(Mombelli A, Van Oosten MAC, Schürch E, Lang NP. The microbiota associated with successful or failing osseointegrated titanium
implants. Oral Microbiol Immunol 1987; 2: 145–51.)
(El-Askary AS, Meffert RM, Griffin T. Why do implants fail? Part I. Implant Dentistry. 1999; 8:173–183.)

52. D.Regenerative and resective therapy (supportive therapy protocol D)
• Only if infection is controlled successfully, as evidenced by an absence of
suppuration and reduced edema, further treatment to restore the bony
support of the implant by means of regenerative techniques or to
reshape the peri-implant soft tissues and/or bony architecture should be
done.
• It is recommended to remove the prosthesis 8 weeks prior to surgical
treatment in order to ensure optimal results of oral hygiene practices
and allow the soft tissue to heal and collapse around the implant sites
• The first step in surgical therapy is to degranulate the defect. It is
followed by exposing and treating the bacterially contaminated implant
surface.

53. • If the surface is clean and detoxified, with all exposed areas of the implant
visualized and instrumented, it is possible to graft with an allograft
material such as DFDBA to achieve biologic healing.
• If the implant surface cannot be cleaned and detoxified due to vents,
holes in the implant fixture, it is advisable to graft with an alloplast
material such as HA or Bioactive Glass.
• The resective osseous surgery is indicated to reduce pockets and bone
recontouring to correct negative architecture of bone . This include
Resection techniques including ostectomy, with the raising of an apical
repositioning flap, and implantoplasty.

54.  CALCIUM HYDROXIDE PASTE AS A SURFACE DETOXIFYING AGENT FOR
INFECTED DENTAL IMPLANTS: CASE REPORT
 Dennis Flanagan.
 Journal of Oral Implantology, 2009.
 A 44-year-old woman with failing endodontically treated maxillary central
incisors presented for treatment and after extraction of two incisors two
implants were placed.
 After4 months of healing,
1 implant was placed in site #11 (3.7
 13, Implant Direct, Ventura, Calif). Site #21
had poor bone quality for initial stabilization,
therefore, the osteotomy was compressed with
an osteotome and a larger implant was installed.

55.  At the eighth postoperative week, the patient presented with a small facial
swelling at site #21. A drainage tract was seen and a radiograph was made
with a #40 gutta percha point placed into the tract to act as an indicator to
the source.
 The site was locally anesthetized and surgically opened. The area was
debrided with a periodontal curet, treated with calcium hydroxide
paste(30 sec).
 An allograft material was then placed in the defect (Puros), and a barrier
membrane was placed

56.  Removal of failed implant.
 The techniques of removal of failed implants include use of a counter-
torque ratchet, Piezo tips, high-speed burs, elevators, forceps, reverse
screw and trephine burs and combinations of these tools.
 Use of the counter-torque ratchet is the least invasive technique for
removing an implant. It is screwed into a failed implant and reverse
torqued. It works well in the maxilla.
 In the mandible, where the bone is denser, it is advisable to use a bur 360
degrees around an implant to remove bone at least one-half its length
before counter torquing.
THE TREATMENT OPTIONS FOR MANAGING IMPLANT FAILURE

57. Hopeless implant
Fracture
Screw not
engageable
Screw
engageable
Bone
removal
techniques
Reverse
screw
technique
No fracture
With internal
connection
No internal
connection
Screw not
engageable
Screw
engageable
Bone
removal
techniques
Ratchet
engageable
Ratchet not
engageable
Counter torque
ratchet technique
Bone removal techniques
METHODS OF IMPLANT REMOVAL
(Mantena SR, Gottumukkala SNVS,
Sajjan S, Rama Raju A, Rao B, Iyer M.
Implant Failures—
Diagnosis and Management. Int J Clin
Implant Dent 2015;
1(2):51-59.)

58. o DENTAL IMPLANT REIMPLANTATIONS
 Delayed Reimplantation after loss of an implant.
• When an implant is lost, a flap should primarily cover the entrance to the site
and after 9-12 months, a new implant can be replaced at that site.
• New implants are larger in length and diameter than the implants placed first.
 Immediate Reimplantation after loss of an implant
• Failure rates after implant removal were not significantly different between
delayed and immediate reimplantations.
• If there is adequate bone to achieve primary stability, delayed placement does
not appear to provide any advantages.

59. TREATMENT ALTERNATIVES FOLLOWING REMOVAL OF FAILED DENTAL
IMPLANTS
Removed failed dental implant
Re-evaluate original treatment plan
Implant not critical for
restoration
Proceed to final
restoration
Critical for
restoration
Consider redoing the implant
Place new implant in
an adjacent site
Perform new implant at
same site
Revise treatment
plan to hybrid
implant tooth
FPD/Tooth supported
FPD/RPD
Unsuccessful successful
Consider second
re-do
or

60.  Treatment of peri-implantitis using an Er:YAG laser or an air-abrasive
device: a randomized clinical trial.
 Renvert S, Lindahl C, Roos Jansa˚ker A-M, Persson GR.
 J Clin Periodontol 2011; 38: 65–73.
 Aim- The aim of the present study was to assess the clinical outcomes
following treatment with either a non-surgical debridement using an air-
abrasive device or an Er:YAG laser in subjects with implants and a diagnosis
of periimplantitis.
 Materials and Method
• 42 Subjects were selected which are presented with at least one dental
implant with bone loss. and having a PPD >5 mm with bleeding on probing.

61. • Twenty-one subjects in each group were randomly assigned to one time
intervention by an air-abrasive device or an Er:YAG laser. Clinical data were
collected before treatment and at 6 months.
 Results-
• No baseline subject characteristic differences were found. Bleeding on
probing and suppuration decreased in both the groups.
• 25% of the subjects in the laser group had an average PPD reduction 1.0
mm whereas 38% of the subjects in the air-abrasive group had an average
PPD reduction 1.0 mm.
• The average change in the bone level was a loss of 0.3 mm for the laser
group and a loss of 0.1 mm bone height for the air-abrasive group.
 Conclusion- Air- abrasive group shows better clinical out come than laser
group.

62.  Prognosis of the implants replaced after removal of failed dental implants.
 Young-Kyun Kim, Jin-Young Park, Su-Gwan Kim.
 Int J Oral Maxillofac Implants ;2016.
 Aim- This study was carried out to evaluate the survival rate and condition
of tissue surrounding the replaced implants after removal of failed
implants.
 Materials And Methods-
• This study examined 60 implants ( 39 implants in men, 21 implants in
women) in 49 of these patients (35 men, 14 women).
• The following parameters associated with the implants were measured
and analyzed: the area in which the implant failed, the surgical methods
performed in the first placement, the surgical methods performed in the
second placement, the biomaterials used in the first placement, the
biomaterials used in the second placement.

63.  Results-
• The most frequent site of implant failure was the maxillary first molar area.
• The percentages of cases of immediate and delayed replacement were
48.3% and 51.7%, respectively. The average healing time for patients
undergoing delayed replacement was 2-3months.
• No significant difference in the failure rate of the second implant was
observed between the immediate and delayed replacement groups.
• The marginal bone loss at the final follow-up (22-24) months after
implantation) was 0.33-0.49 mm, the width of attached gingiva was 1.68-
2.11 mm, the plaque index was 0.81-1.05, the gingival index was 0.56-
0.63, and the pocket depth was 3.33-1.21 mm.
 Conclusion- Implant failure occurred most frequently in the maxillary first
molar area. We can improve the survival rate of replaced dental implants
after removing the initial failed implant using various bone grafting
techniques and/or additional implant fixture.

64. Bibliography
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65. Conclusion
• Failure of implant can be multi-factorial. Often many factors come
together to cause the ultimate failure of the implant. One needs to
identify the cause not just to treat the present condition but also as a
learning experience for future treatments. Proper data collection, patient
feedback, and accurate diagnostic tool will help point out the reason for
failure. An early intervention is always possible if regular check-up are
undertaken.