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Prevention and Management Of Complications

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Title: Prevention and Management Of Complications


1
Prevention and Management Of Complications In
Implant Dentistry
2
Evidence Based Medicine / Dentistry
  • EBM is the conscientious, explicit and judicious
    use of best evidence in making decisions about
    care of individual patients.

Cochrane Center Oxford, England
3
3 Components of Evidence Based Dentistry
  • 1) Scientific Literature
  • 2) Professional Experience and advise
  • 3) Patients treatment desire and goal

4
Train The Brain
Dr. Mark H.E. Lin
5
(No Transcript)
6
  • Medical Status
  • Absolute Contraindications to Surgery
  • Relative Contraindications / Risk Factors to
    Surgery

Host / Patient Related
  • Susceptibility to Infections and healing response
    in question

7
  • Medical Status
  • Absolute Contraindications
  • For Surgery (Dental alveolar, implant, hard or
    soft tissue grafting)
  • Debilitating diseases
  • Active cancer
  • chemotherapy
  • radiation therapy
  • transmittable infections- hepatitis, HIV
  • Impaired healing capacity diseases
  • Uncontrolled diabetes
  • Uncontrolled hypertension
  • immune compromised disease
  • history of osteomylitis in operative site

Host / Patient Related
8
  • Medical Status
  • Absolute Contraindications
  • Recent myocardial infarction (M.I.),
    cerebrovascular accident, uncontrolled clotting /
    bleeding disorders
  • Pregnancy
  • Chronic or severe alcoholism
  • Drug abuse
  • Psychiatric disorders
  • I.V. bisphosphonate use or long term oral
    bisphosphonate
  • Uncontrolled periodontal disease
  • ASA IV or V patients

Host / Patient Related
9
  • Medical Status
  • Relative Contraindications / Risk Factors
  • For Surgery (Dental alveolar, implant, grafting)
  • Debilitating diseases Inactive cancer
  • Impaired diseases Controlled diabetes,
    controlled hypertension
  • Myocardial infarction (M.I.) history of gt1 year
  • Oral bisphosphonate
  • Smoking habits
  • Periodontal disease

Host / Patient Related
10
American Society of Anesthesiologists (ASA)
Classifications
  • ASA I a normal, healthy patient, without
    systemic disease.
  • ASA II a patient with mild to moderate systemic
    disease.
  • ASA III a patient with severe systemic disease,
    which limits or alters activity but is not
    incapacitating.
  • ASA IV a patient with severe systemic disease,
    which is incapacitating and is a constant
    threat to life.
  • ASA V a moribund patient not expected to live
    more than 24 hours without an operation.

11
Elective Implant surgeries are NOT indicated for
ASA IV or V patients
12
For a patient at risk, strict adherence to the
standard protocol does not always yield the
expected results.
13
Infection
  • Invasion and multiplication of microorganisms in
    body tissues, which may be clinically inapparent
    or result in local cellular injury due to
    competitive metabolism, toxins, intracellular
    replication, or antigen-antibody response.
  • Dorlands Illustrated Medical Dictionary 27th,
    Edition

14
Factors Associated with Increased risk of
infection for dental implant procedures
  • Systemic Factors
  • Diabetes
  • Long term corticosteroid use
  • Immunocompromised systemic disorders
  • Smoking
  • Malnutrition, obesity
  • Elderly population
  • ASA III or IV classifications

15
Factors Associated with Increased risk of
infection for dental implant procedures
  • Local Factors
  • Use of type or procedures of graft material
  • Generalized periodontal disease
  • Tissue inflammation
  • Odontogenic infections
  • ill-fitting provisional prosthesis
  • Incision line opening
  • Inadequate oral hygiene

16
Factors Associated with Increased risk of
infection for dental implant procedures
  • Surgical Factors
  • Poor aseptic technique
  • Compromised skill and experience of the surgeon
  • Increased duration of surgical time
  • Wound contamination during surgery
  • Foreign body introduction (graft material,
    implants, debris, etc.)

17
Infection Prophylaxis
  • Aseptic Surgical techniques applied during all
    clinical grafting procedures.

2) Pre-operative Rx Amoxicillin 500mg x 4
tablets (2 g), 1 hour prior to surgery
(Scientific Evidence) Post-operative 1 tablet
t.i.d. for 1 week following surgery (Optional)
18
Infection Prophylaxis
  • 3) Chemical Plaque control
  • Preoperative rinsing with .12 Chlorhexidine
    digluconate for 1 minute.
  • Postoperative rinsing for 2-3 weeks with good
    oral hygiene.

4) Monitor and close follow up Patient to
return to clinic at 1-2 weeks to evaluate
healing status.
19
Infection Prophylaxis
  • 5) Confirm lack of localized infection from
    adjacent tooth (endodontic origin) or soft
    tissues (periodontitis) spreading into grafting
    site.

20
Diabetes
  • Higher prevalence in Adult African Americans,
    native and Hispanic Americans
  • Risk factors Genetics, obesity, advancing age
    and inactive lifestyles.
  • Characterized by
  • Peripheral resistance to insulin
  • Increased production of glucose by the liver
  • Altered pancreatic insulin secretion.

21
Oral Manifestations for a Diabetic Patient
  • Poor wound healing (soft tissues,
    osseointegration)
  • Higher susceptibility to oral infections
  • Xerostomia
  • Higher incidence of dental caries
  • Pronounced hyperplasia of attached gingival
  • Increased accumulation of plaque and food debris
  • Neuropathy (burning mouth, tingling, numbness)
  • Greater incidence and severity of periodontal
    disease
  • Candidiasis and lichenoid reactions

22
Signs of Hypoglycemia
  • Sweating
  • Palpitations
  • Tachycardia
  • Nausea
  • Hunger
  • Tremulousness
  • The symptoms may progress to coma and convulsions
    without intervention.

23
Management of type I diabetic patients (To
prevent Insulin shock)
  • Patient instructed to take their usual dosage of
    insulin medications
  • To eat a normal meal prior to appointment
  • Schedule the appointment early in the morning
  • Patient to communicate with dentist if they feel
    symptoms of an insulin reaction
  • A source of sugar available in office (orange
    juice, candy, sugar packs)
  • May consider Antibiotic prophylaxis coverage to
    prevent infections which is related to the
    fasting blood glucose levels.

24
Dental Managements
  • Minimize stress
  • Decrease risks of infection (Post operative
    antibiotics Amoxicillin 500 mg, t.i.d. or
    Clindamycin 300 mg, t.i.d. for 7-10 days)
  • Avoid untoward metabolic imbalances during dental
    therapy
  • Instructions for diet and medications to avoid
    hypoglycemia.

25
Management of Hypoglycemia
  • Sugar source readily available (sugar packets,
    candy, orange juice)
  • Dextrosol 3mg tablets of glucose
  • Glucagon 1 mg IM
  • 50 Glucose solution 50 ml IV

26
Bisphosphonates Induced Osteonecrosis of the Jaws
(ONJ)
  • Defined as a non healing bone in the mandible or
    maxilla present for 8 weeks in a person that is
    on Bisphosphonates and hasnt received radiation
    to the jaws.

27
Risk of osteonecrosis of the jaws
  • Exposed bone is dead with usually no pain.
  • Pain may occur due to secondary infection
  • The jaw bones are susceptible because the jaw
    bone remodels 10 times that of long bones in the
    body.

28
Bisphosphonates
  • Used for treatment of osteoporosis, metastatic
    bone cancer and Pagets disease.
  • Oral form Fosamax, Boniva, Actinol
  • IV form Aredia, Zonita

29
Mechanism of Bisphosphonates
  • Mechanism of action by suppressing and reducing
    bone resorption by osteoclasts.
  • Bisphosphonates inhibit osteoclasts by killing
    them when they take up the drug during
    resorption.
  • Bisphosphonates binds to the hydoxyapatite in the
    bone

30
Bisphosphonates
  • IV medications are worse then oral types.
  • Risk increase after being on oral medications for
    gt 3 years.
  • IV takes 6 months to build to toxic level
  • Oral takes 3 years to build to toxic level
  • 140 IV reported cases versus 40 Oral cases
  • Incidence IV .8-12
  • Incidence Oral .01-1

31
Signs of ONJ
  • Sclerosis and thickening of the lamina dura
  • Widening of the periodontal ligament (PDL)
  • Mobile teeth with pain
  • Exposed bone with necrosis of bone and soft
    tissues
  • Non healing bone post surgical wound

32
Treatment of ONJ
  • We dont know what is the best treatment
    protocol. Dr. Robert Marx seems to be the expert
    on this topic.
  • Peridex rinse over surgical wound
  • Antibiotics a) Pen VK
  • b) Levoquin (limit to 21 days due to
    liver toxicity)
  • Reduce risk of secondary infections and
    osteomylitis of the jaws.
  • 50 of cases will spontaneously heal.
  • 50 of cases will require additional surgeries.

33
Prevention of ONJ
  • Non invasive dental procedures are safe.
  • Invasive dental procedures safe before 3 years.
  • After 3 years- a drug holiday with consent of
    prescribing physician to a CTX of gt 150 pg/ml.

34
Serum C terminal telopeptide test (CTX)
  • After 3 years of Bisphosphonate use, need a CTX
    to determine safety level.
  • CTX lt 100 pg/ml HIGH risk
  • CTX 101-150 pg/ml Moderate risk
  • CTX gt 150 pg/ml Low risk
  • CTX improves significantly with discontinued oral
    Bisphosphonates use.
  • CTX is a marker for bone turnover and healing.
  • Measures osteoclast function as a C terminal
    fragment is cleaved during bone resorption.

35
Suggested Treatment Regimen
  • 1) Obtain references for CTX level
  • 2) Drug holiday of 4-6 months with approval
    from prescribing physician.
  • 3) Treat with Peridex (.12) and antibiotics.
  • 4) Monitor CTX until value is gt150 pg/ml
  • 5) Decide to refer or monitor for treatment
    options
  • A) Spontaneous resolution
  • B) Treat surgically

36
  • Psychological Status
  • Psychological and mental stability for patient to
    accept and tolerate required procedures
  • Normal healing response and sequelae of bone and
    soft tissue grafting procedures
  • The 3 Cs prior to treatment
  • a) Communication
  • b) Compliance
  • c) Consent

Host / Patient Related
37
Host / Patient Related
  • Normal healing response and sequelae of bone and
    soft tissue grafting procedures are
  • Hemorrhage / bleeding
  • Ecchymosis / bruising
  • Pain / discomfort
  • Swelling

38
Hemorrhage / bleeding Management
  • 1) Management of intra operative bleeding source
    (soft tissue / bone) prior to suturing.
  • 2) Proper soft tissue suturing techniques to
    ensure primary closure without tension of soft
    tissues.
  • 3) Proper use of sterile gauze pads with
    moistened sterile saline solution with FIRM
    pressure over wound for 20 minutes.
  • 4) Oral and written instructions for care to
    prevent vasoactive substance (caffeine or
    alcohol), minimize exercise, post operative care
    to minimize disturbance to wound clotting, oral
    hygiene instruction care.

39
Ecchymosis (Bruising)
  • Due to extravasation and subsequent breakdown of
    blood in the subcutaneous tissues.
  • Deposition of blood from the surgery in the
    interstitial tissues spaces and will be resorbed
    over a time period of 1-3 weeks.
  • Occurs more in fair skinned patients and elderly
    patients with fragile capillaries.

40
Ecchymosis Management
  • 1) Inform patient that it will be a normal
    sequelae of any surgical procedure.
  • 2) Inform patient that degree of bruising is NOT
    an indicator of success / failure, traumatic /
    atraumatic nature of procedure or operator.
  • 3) Application of ice bag or cold packs
    immediately after surgery for 2 days.

41
Pain / discomfort Management
  • Long term Local anesthetics
  • Bupivacaine (Marcaine / Vivacaine) 0.5 w
    1200,000 epinephrine used for block anesthesia.
    Duration time of 6-8 hours.
  • Articaine (Ultracaine Forte / Astracaine) 4 w
    1 200,000 epinephrine. Duration time of 4 hours.
  • Analgesics
  • a) NSAIDS Ibuprofen 400mg (600-800mg if
    anticipate swelling), 1 hour prior to surgery,
    then 1 tablet every 6-8 hours continuous for 2-3
    days.
  • b) Narcotics Tylenol 3, 1-2 tablets every 4-6
    hours as required for pain relief.

42
Swelling Management
  • 1) Application of ice bag or cold packs
    immediately after surgery for 2 days.
  • 2) I.V. administration of glucocorticoid
    steroids (prednisolone 250mg or dexamethasone 8
    mg) prior to start of surgery.
  • 3) I.M. administration of Dexamethasone /
    Decadron (Celestone Soluspan Injectable)6mg/per
    site adjacent to surgical wound.
  • P.O. prescription of Dexamethasone (Decadron) 4
    mg with regimen as follows
  • Preoperative 4mg x 2 tablets 8 mg, 1hour prior
    to surgery
  • Postoperative 4mg x 1 tablet 4 mg, 1st day
    after surgery
  • Postoperative 4mg x .5 tablet 2 mg, 2nd day
    after surgery
  • Postoperative 4mg x .5 tablet 2 mg, 3rd day
    after surgery

43
Complication
  • A secondary disease or condition aggravating an
    already existing one.

Dorlands Illustrated Medical Dictionary 27th,
Edition
44
Complication
  • Defined as a secondary condition that developed
    during or after implant surgery or prosthesis
    placement. The occurrence of a complication does
    not necessarily indicate that substandard dental
    care was provided and also does not necessarily
    mean that clinical failure has occurred.

45
Sequelae
  • Any lesion, condition, consequence or affection
    following a clinical procedure injury or caused
    by an attack of previous disease.
  • Dorlands Illustrated Medical Dictionary
    27th, Edition

46
a) Communication
  • Share or exchange information, news, or ideas
  • Oxford Dictionary 10th Edition

Allocate appropriate amount of TIME to educate
and communicate prior to consent to treatment.
Utilize patient education video, documents and
software to aid in communication process.
47
b) Compliance
  • Disposed to agree with others or obey rules,
    especially to an excessive degree. Meeting or in
    accordance with rules or standards.
  • Oxford Dictionary 10th Edition
  • A quality of yielding to pressure or force
    without disruption, or an expression of the
    measure of the ability to do so.

Dorlands Illustrated Medical Dictionary 27th,
Edition
48
COMPONENTS OF CASE MANAGEMENT FOR IMPROVED CASE
ACCEPTANCE RATE
New Patient Telephone Interview
New Patient First Appointment Interview/
Consultation Interview
Diagnostic Records Appointment
- Consult with Specialists and Labs
Case Presentation(Within 1 Week), (Bring Spouse)
Acceptance
Pending
Case Discussion Letter
Pre-Appointment Work Up -Pre Medications -Inform
Consents -Financial Arrangements
Confirmed -Diagnostic Work Up -Q/A Period
Follow Up Report(1wk, 2 wks, 1 months)
Post Treatment Interview -Follow Up photos for
Patients B/A -Request for Testimonial
Letter -Referral Request
Treatment
49
c) Consent Process
  • Communication and patient education
  • Process of informed consents and financial
    arrangements confirmed
  • Relationship and rapport development with
    patients
  • Continuous monitoring support, empathy and
    sincere compassionate care

50
Consequences of Smoking on wound healing
  • Arteriolar vasoconstriction reduces
    vascularization and microcirculations of
    tissues.
  • May lead to increase incidence of flap necrosis
    and dehiscence to early graft exposures.
  • Tobacco's toxic byproducts have been implicated
    as risk factors for impaired healing.

51
Studies on Smoking and Implants
  • Study 1 5 lost on non-smokers versus 11 on
    smokers. Smokers with higher implant failure
    rates in all regions except for the posterior
    mandible.
  • Study 2 3 lost on non-smokers versus 7 on
    smokers by number of implants. 9 lost on
    non-smokers versus 22 on smokers by number of
    patients. Regardless of method of analysis, a
    SIGNIGICANT difference was noted between smokers
    and non-smokers.

52
Studies on Smoking and Implants
  • Study 3 Smoking cessation protocol of 1 week
    before surgery and 8 weeks after surgery.
  • -6 implant lost on non-smokers.
  • -38 implant lost on smokers WITHOUT smoking
    cessation program.
  • -12 implant lost on smokers WITH smoking
    cessation program.
  • Cessation protocol demonstrated improving implant
    success on treatment of smokers.

53
Effect of smoking (evaluated in 9 studies)
  • -Significantly increases implant loss
  • -Consumption increases failures (2 studies)
  • -Consumption does note increase failure (1 study)
  • -Comparison (smokers/nonsmokers)
  • 178 / 1668 implants lost in smokers (11)
  • 239 / 4862 implants lost in non-smokers ( 5)

54
Management protocol for smokers
  • Dont treat!
  • Smoking cessation programs
  • Treat with consent form

55
Tobacco and Nicotine Warning Consent forms
56
Periodontal disease and Dental Implants
  • Implant survival in patients with a history of
    treated Periodontitis ranged from 59-100
  • 17/18 studies reported high implant survival
    rates of gt 90 with turned or moderately rough
    implant surfaces
  • Need for continue regular supportive periodontal
    therapy
  • Statistically significantly greater risk of
    peri-implantitis, odds ratio of 3.1 to 4.7

57
Iatrogenic
  • Any adverse condition in a patient occurring as
    the result of treatment by a physician / dentist
    or surgeon, especially to infections acquired by
    the patient during the course of treatment.
  • Dorlands Illustrated Medical Dictionary 27th,
    Edition

58
Implant Treatment Planning
  • Implantology is a Prosthetically / Restorative
    driven discipline with a Surgical component.

59
Treatment Sequence
Esthetic Implant Dentistry, Patrick Palacci, DDS
60
Improper Implant Treatment Planning
  • Improper surgical implant placements without
    desired prosthetic goals treatment planned
  • Improper use of number and location of dental
    implants for final prosthesis
  • Lack of understanding of Biomechanical rationale
    requirements for functional loads

61
Pretend the following-you had all the time
-you had all the money-you had all the
bone-you had all the compliance
  • What is the most ideal treatment plan desired for
    your patient?

62
Treatment planning philosophy- one of the most
important factor to success
  • Dont compromise your ideal treatment plan with
    the following
  • -patients financial constraints.
  • -unreasonable time demands for completion.
  • -insurance limitations or moral compromises.
  • -patients guidance on treatment decisions.
  • (i.e. less implants, omit required grafting, use
    of material, etc.)

63
The Lost Syndrome
  • 1) Lost trust from the patient!
  • 2) Lost patience from the patient who will
    require more surgeries and procedures!
  • 3) Lost time and require to start again from a
    clinical condition in a MORE compromised state!
  • 4) Lost clinical chair time to redo the case!
  • 5) Lost lots of money to redo the case!
  • 6) Lost of peace of mind! (Lawsuit or
    Regulatory College Complaint?)

64
Treatment planning philosophy- one of the most
important factor to success
  • My rule on Treatment Planning
  • Only treatment plan and execute implant treatment
    as you would for your own family members.

65
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66
Improper use of number and location of dental
implants for final prosthesis
67
Lack of understanding of Biomechanical rationale
requirements for functional loads
68
Biomechanical rationale
69
Definitions
  • Bone Remodeling- turnover or internal
    restructuring of previously existing bone.
  • It is a coupled tissue level phenomenon.
  • Activation- of osseous precursor cells.
  • Active Resorption.
  • Reversal or Quiescence.
  • Formation.
  • Remodeling cycle called Sigma- in humans is 17
    Weeks.

70
Definitions
  • Strain- the change in length divided by the
    original length and the units of strain are given
    in percent.
  • Too much bone strain at the implant interface
    causes bone loss.
  • The strain to bone may be caused by the stress
    applied to the prosthesis.

71
Stress _____
72
Mechanism of Implant Failure
Occlusal overload
Microdamage
Increased bone remodelling rate
Histological change in bone at implant interface
and adjacent bone
Increased effect of magnitude of strain
73
Stress Factors
  • Excess stresses to an implant / bone interface
    will cause overload and implant failure.
  • Complications from Stress
  • -implant integration failure with fibrous tissue
    formation around implant, mobility instead of
    rigid fixation.
  • -Early crestal bone loss.
  • -Occlusal overload bone loss
  • -Screw loosening (prosthesis or abutment)
  • -Implant fracture (body or component)
  • -Prosthesis fracture (occlusal material or
    framework)

74
5) Clinical Force factors
  • 1) Bite Forces (light vs. normal vs. heavy)
  • 2) Parafunction
  • 3) Crown implant height ratio
  • 4) Masticatory Dynamics
  • 5) Opposing Arch
  • 6) Direction of load
  • 7) Nature of Opposing Arch
  • 8) Position of Abutment in the arch
  • 9) Occlusal scheme

75
1) Bite Forces (light vs. normal vs. heavy)
  • Implant supported Fixed Prosthetics gt
  • Implant supported Removable Prosthetics gt
  • Natural dentition with Porcelain Prosthetics gt
  • Natural dentition gt
  • Partial Removable Prosthetics gt
  • Full Removable Prosthetics

76
2) Parafunction
  • Repeated or sustained non-functional wear that
    is harmful to the stomatognathic system.
  • A) Bruxism- vertical or horizontal nonfunctional
    grinding of teeth. A maximum bite force recorded
    at 990 psi (4-10 times normal)
  • B) Clenching- a habit that generates a constant
    force exerted form 1 occlusal surface to the
    other without any lateral movement. Bruxing and
    clenching can exist in combination.
  • C) Tongue Thrust and Size- unnatural force of
    the tongue against the teeth during swallowing.

77
Character Of Forces
  • A) Force Magnitude (heavy, medium, light)
  • B) Force Duration
  • C) Force Type (Compressive, tensile, shear)
  • D) Force Direction
  • E) Force Magnifiers (Horizontal and vertical
    cantilevers)

78
Surface Area for maximal Bone / implant
interface contacts
79
Options To Increase Surface Area
  • 1) Increase Implant Numbers
  • 2) Increase Implant Size and Length
  • 3) Implant Design
  • 4) Implant Surface conditioning
  • 5) Bone Density

80
Surface Area for maximal Bone / implant
interface contacts.
  • 1) Maximize implant number.
  • 2) Maximize implant diameter.
  • 3) Maximize implant length.
  • (Without violation of the limits of bone volume
    or anatomical structures.)
  • 4) Bone Density Classification
  • D1- Dense cortical ( gt 1250 Hounsfield units)
  • D2- Porous cortical and coarse Trabecular (
    850-1250 H. units)
  • D3- Porous cortical (thin) and fine Trabecular
    (350-850 H. units)
  • D4- Fine Trabecular (lt 150 H. units)

81
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82
Goals of Diameter Of Implant
  • Increase surface area
  • Compensate for unfavorable patient bite force
    factors
  • Minimize cantilevers for angled implants
  • Compensate for poor bone density
  • Enhance surface for shorter implants
  • Improve emergence profile
  • Decrease screw loosening
  • Minimize component fracture
  • Facilitate oral hygiene

83
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84
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85
Approximate Surface Area Of Anterior Natural
Dentition (mm2)
  • Jepsen, A root Surface Measurement and a Method
    for x-ray determination of Root Surface, Acta
    Odontol., Vol.2135, 1963

86
Approximate Surface Area Of Posterior Natural
Dentition (mm2)
  • Jepsen, A root Surface Measurement and a Method
    for x-ray determination of Root Surface, Acta
    Odontol., Vol.2135, 1963

87
Goals of Length Of Implant
  • Increase surface area
  • Compensate for unfavorable patient bite force
    factors
  • Gain initial ridged fixation of dental implant
  • Compensate for poor bone density
  • Not violate any vital anatomical anatomy (IAN,
    mental nerve, sinus, lingual concavities, nasal
    foramen, adjacent roots, etc.)

88
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89
Classification Of Oral Implant Failures
  • 1) Biological
  • A) Early or Primary (before loading) Failure to
    establish osseointegration.
  • B) Late or Secondary (after loading)
  • Failure to maintain the achieved
    osseointegration.

90
Early or Primary (before loading) Failure to
establish osseointegration.
  • 1) Inadequate quantity and quality of bone for
    initial fixation of dental implant.
  • 2) Experience of surgical operator.
  • 3) Over heating of bone during osteotomy
    preparations.
  • 4) Pressure necrosis, especially in D1 bone.
  • 5) Infection operatively after initial surgery.
  • 6) Incision line opening leading to
    complications or infections.

91
Goodacre C, JPD 2003
92
Classification Of Oral Implant Failures
  • 2) Mechanical
  • Fracture of implants, connecting screws, bridge
    frameworks, coatings, porcelain, etc.

93
Goodacre C, JPD 2003
94
Iatrogenic
  • Treatment planning flaws and complications.
  • Violation of vital anatomical structures.
  • Inappropriate application of procedure to site
    requirement.
  • Compromised surgical skills.
  • Compromised prosthetic skills.

95
Types of Surgical Complications
  • Surgical complications
  • Hemorrhage-related complications
  • Neurosensory complications
  • Mandibular fracture
  • Adjacent Tooth devitalization
  • Life-Threatening hemorrhage
  • Air Emboli
  • Violation of Mandibular canal
  • Aspiration of screwdriver, parts, components

96
Surgical Parameter by REGIONSPosterior Mandible
97
Surgical Parameter by REGIONSPosterior Mandible
  • D2 D3 bone density
  • 1) Problem Mandibular nerve location.
  • Solution Surgical landmark to be at least 2.0
    mm above the mandibular canal to
    establish a surgical zone of safety.
  • Pre-surgical diagnostic workup to measure
    allowed length of implant. Use of periapical and
    panoramic x-rays, tracings, CT scans to verify
    length.
  • Surgical use of directional guide pins to verify
    proximity to mandibular nerve after initial pilot
    osteotomy.
  • Remember The enemy of good is perfection. If
    in doubt, use shorter implant lengths ( at least
    10.0 mm)

98
Posterior Mandible
99
Surgical Parameter by REGIONSPosterior Mandible
  • 2) Problem Lingual concavity and
    angulation flare of posterior mandible.
  • Solution Use of CT scans to perform
    electronic surgery as part of treatment
    planning. Minimal reflection of lingual flap
    to visualize lingual wall of bone
    trajectory. Implant length to meet
    biomechanical requirement without
    anatomical violations.

100
Posterior Mandible
101
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102
Contraindications to posterior single tooth
implant
  • 3) Inadequate bone volume
  • Width-consider grafting or alveloplasty or
    implant placement with guided bone regeneration.
  • Length- Mesialdistal, intratooth space, need gt7
    for a 4.0mm implant with 1.5mm between implant
    and adjacent tooth.
  • Height- no treatment, shorter implants, or
    particulate grafting of exposed threads.

103
Posterior Mandible
104
Posterior Mandible
105
Surgical Parameter by REGIONSAnterior Maxilla
106
Position of Implant placement in 3 DIMENSION
  • Buccal / Palatal Position
  • Implant platform to be at INCISAL EDGE with 1/3
    buccal to edge and 2/3 palatal to edge of
    adjacent teeth.
  • Mesial / Distal Position
  • 1.5-2.0mm between implant and adjacent tooth,
    3.0mm between 2 adjacent implants.
  • Apical / Coronal Position
  • Implant platform to be 3.0 mm apical to free
    gingival margin of adjacent teeth or ideal
    position.

107
Implant Position Related To Retention Mechanism
Cement retained Buccal / Palatal
Position Implant platform to be at INCISAL EDGE
with 1/3 buccal to edge and 2/3 palatal to edge
of adjacent natural dentition.
Screw retained Buccal / Palatal Position
Implant platform to be at CINGULUM aspect
relative to adjacent natural dentition.
108
Maxillary Anterior
109
Maxillary Anterior
110
Maxillary Anterior
111
Maxillary Anterior
112
Palatal placement requires ridge lap and
compromised phonetics
113
Surgical Parameter by REGIONSAnterior Mandible
114
Surgical Parameter by REGIONSAnterior Mandible
  • D1-D2 bone density
  • 1) Problem Overheating during osteotomy
    preparations.
  • Solution Prepare osteotomy with constant
    pumping motion and use higher torque
    speed. Use new drills with copious
    COOLED irrigations and incremental
    drill sequence.

115
Surgical Parameter by REGIONSAnterior Mandible
  • 2) Problem Pressure necrosis of devital
    zone of bone around implants. (Early
    signs of RL around implants during healing
    with symptoms of pain to patient.)
  • Solution Must bone tap with hand ratchet
    each osteotomy site prior to surgical implant
    placement. Reverse torque final
    implant position by 1/4 - 1/2 turn to
    relieve internal stresses and pressure.

116
Maxillary Anterior
117
Surgical Technique Specific For D1-D2 Bone Types
  • 1) Use new and sharp drills for osteotomies.
  • 2) Use chilled saline with internal and external
    copious irrigation.
  • 3) Use Pumping motion to allow osteotomies to
    cool down between advancement in depth.
  • 4) Use marginal enlargement of osteotomies with
    sequential drill sizes.
  • 5) Must bone tap prior to implant placement.
  • 6) After initial implant placement, reverse
    torque implant by ¼ - ½ turn.
  • 7) Can consider immediate or early loading.

118
Surgical Parameter by REGIONSAnterior Mandible
  • 3) Problem Resorption pattern of anterior
    mandible resulting with lingualized
    implant angulations and position.
  • Solution Fabrication of Surgical guides
    from approved wax up of final
    prosthesis. May need to compromise with
    thicker amount of lingual acrylic.

119
Surgical Parameter by REGIONSAnterior Mandible
  • 4) Problem Resorption pattern or
    anatomical pattern resulting in steep
    lingual concavity.
  • Solution Pre-surgically diagnose situation
    with use of lateral ceph radiographs or CT
    scans. Surgical reflection of lingual
    flap with direct vision inspection and
    instrument protection.

120
Resorption pattern
121
Anterior Mandible
122
Surgical Parameter by REGIONSAnterior Mandible
  • 5) Problem Location of Mental foramen with
    or without anterior loop.
  • Solution Locate the mental nerve by
    anatomical location relative to the
    face. Vertical line through pupils of the
    patients eyes passes through infraorbital
    and mental foramen. Finger width lateral
    to ala of the nose also is on this vertical
    landmark.
  • Surgical dissection to identify and
    locate the mental nerve with safety zones
    marked.

123
Anterior Mandible
124
Surgical Parameter by REGIONSPosterior Maxilla
125
Surgical Parameter by REGIONSPosterior Maxilla
  • D3-D4 bone density
  • Problem Violation of Maxillary Sinus
  • Solution Determine need for sinus
    augmentations prior to implant placement.
  • Need minimal of 5.0 mm of autogenous recipient
    bone for simultaneous implant placement with
    sinus graft.

126
Posterior Maxilla
127
Surgical Parameter by REGIONSPosterior Maxilla
  • 2) Problem Bone density with least implant
    contact (50).
  • Solution Use a bone condensing (osteotomes)
    rather than bone removing (osteotomies)
    technique for implant site preparations.

128
Posterior Maxilla
129
Implant Prosthetic concepts
130
Implant Prosthetic Concepts
  • 1) Minimize ( lt 3 units ) number of pontics.
  • 2) No Cantilevers (especially distal)
  • 3) No Connection to natural teeth.
  • 4) Splinting of implant crowns.
  • 5) Minimize facial / lingual occlusal table.
  • 6) Implant protected occlusal scheme.
  • 7) Progressive bone loading concept on softer
    bone.

131
Splinting of implant crowns
132
Splinting of implant crowns
133
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Dont Do This!
135
4) Occlusal load axial to implant body angle
136
5) Low cusp angle of crowns
137
7) Cantilever or offset distance ( Horizontal
offset)
138
Indications For Open Tray Impression Technique
  • 1) Require adequate access for prosthetic open
    tray impression copings. (Anterior regions of
    mouth.)
  • 2) Multiple units to register accurate
    relationship by indexing of impression copings.
  • 3) Allow impressions with Divergent angulated
    dental implants.
  • Usually require custom impression trays or
    altered disposable trays.
  • Must verify seating with radiograph
  • Consider indexing with resin pattern

139
Indications for Closed Tray Impression Technique
  • 1) Require minimal access for prosthetic closed
    tray impression copings. (Posterior regions
    mouth.)
  • 2) Single or quadrant units.
  • 3) Allow impressions with Parallel alignment of
    dental implants.
  • 4) Usually require stock impression trays or
    disposable trays.
  • Must verify seating with radiograph.
  • Plug screw hole to avoid positive impression
    registration

140
Implant Protected Occlusion
  • 1) No premature occlusal contacts or
    interferences. Timing of occlusal contacts
    protected by natural dentition.
  • 2) Influence of surface area
  • 3) Mutually protected articulation (No lateral
    excursion)
  • 4) Occlusal load axial to implant body angle
  • 5) Low cusp angle of crowns
  • 6) Crown Height (vertical offset)
  • 7) Cantilever or offset distance ( Horizontal
    offset)
  • 8) Implant crown contour (narrow B /L
    dimensions)
  • 9) Selection of occlusal materials
  • 10) Verify implant supported prosthesis have
    lightened occlusion where shim stock (12 um)
    pulls through in C.O. or M.I.P.

141
Implant Protected Occlusion
142
The Maintenance Requirement
  • Post insertion 1 week later- verification of soft
    tissue health and implant protected occlusion
  • 2) Post insertion follow up every 4 months for
    the first year after loading of prosthesis-
    verification of crestal bone changes with
    radiograph, soft tissue health and implant
    protected occlusion
  • 3) Post insertion follow up every 6 months for
    the second year and beyond.

143
3) Prosthetic Parameters
  • Biomechanical rationale
  • Implant Prosthetic concepts
  • Implant provisionalization options
  • Open versus Closed tray impression
  • Screw versus cement retention
  • Implant protected occlusion
  • Management protocol for parafunctional habits
  • Management Options For Compromised
    Interocclusal distance

144
  • Management protocols specific for patients with
    parafunctional habits

145
Force Factors
  • 1) Magnitude (light, normal, heavy)
  • 2) Duration (day time, night time)
  • 3) Frequency (number / unit time)
  • 4) Direction (vector of forces)
  • Type (compression, tensile, shear)
  • Magnifiers (height, cantilevers, parafunctional
    habits)
  • 6) Combination

146
Strategies To Manage Parafunction Forces
  • 1) Educate patient of parafunctional habits.
  • 2) Placing increased number of implants.
  • 3) Placing larger diameter implants.
  • 4) Placing implants in positions to reduce
    bending overload or positions to promote axial
    loading.
  • 5) Avoid use of cantilevers or pontics.
  • 6) Use bruxism night guard appliances.
  • 7) Increasing time intervals during prosthetic
    restoration stages for progressive loading
    protocol.
  • 8) Paying diligent attention to occlusal contact
    design for Implant Protected Occlusion and
    axial loading.
  • 9) Alter occlusal material of prosthetic teeth
    to be acrylic resin for removable prosthesis and
    metal occlusal for fixed prosthesis.

147
Incidence Rate Of Mechanical Complications
  • OD loss of retention or adjustments 30
  • Resin acrylic veneer facture of FPD 22
  • OD relines required 19
  • OD clip / attachment fractures 17
  • Prosthesis screw loosening 7
  • Abutment screw loosening 6

148
Implant Prosthetic Complications
149
Implant Prosthetic Complications
150
Space Requirements for Bar-Overdenture
  • -Thickness of soft tissue 2.0 mm
  • -Hygiene space under bar 1.5 mm
  • -Thickness of bar 4.0 mm
  • -Clip and housing 1.5 mm
  • -Acrylic denture base 2.0 mm
  • -Denture tooth 3.0 mm
  • Total Height Requirement 14.0 mm
  • Compromised Height is 10.5-14.0 mm (bar touching
    soft tissue, reduce thickness of bar, attachment
    type altered, reduce thickness of acrylic base
    and denture tooth size.

151
Implant Prosthetic Complications
152
Implant Prosthetic Complications
153
Inter-Occlusal Space Recommendations
  • 1) lt 3.0 mm abutment height- Use screw
    retention.
  • 2) 3.0-4.0 mm abutment height- Use screw
    retention or vary cement type to make
    non-retrievable.
  • 3) gt 4.0 mm abutment height- Use retrievable
    cement.

154
Implant Prosthetic Complications
155
Incidence Rate Of Mechanical Complications
  • OD loss of retention or adjustments 30
  • Resin acrylic veneer facture of FPD 22
  • OD relines required 19
  • OD clip / attachment fractures 17
  • Prosthesis screw loosening 7
  • Abutment screw loosening 6

156
Implant Prosthetic Complications
157
Broken Attachments
  • Plastic bar clip
  • damaged or broken
  • cut along long axis with sharp knife and remove.
  • Missing
  • replace by inserting a new clip into denture base
    receptacle
  • if unavailable, contact Command Implant
    Coordinator

158
Broken Attachments
  • Metal bar clip
  • damaged or broken (replacement clip available)
  • remove the clip and perforate the denture base
    carefully for intraoral pick up replacement.
  • Block out under the bar with wax, seat the
    denture and position a new clip through access
    in denture base.
  • Use autopolymerizing acrylic resin with bead
    brush technique to fill in access and connect
    clip to denture base. Polish , disinfect and
    deliver.
  • Always confirm seating of denture after repair
    and evaluate occlusion.

159
Broken Attachments
  • Metal bar clip
  • Damaged or broken (replacement clip not
    available)
  • remove all remnants of the clip from the denture
    base.
  • block out under the bar with wax
  • reline the clip area of the denture with a
    resilient chair side reline material (viscogel).
  • Intact clip with no retention
  • carefully bend the leaves of the clip toward the
    bar with a thin instrument.
  • Reseat the denture to confirm increased
    retention.
  • Recheck occlusion.

160
Broken Attachments
  • Stud attachments
  • treatment is similar to clips
  • tease out O ring with an explorer and replace
    as needed.
  • Fractured housing can be treated like a clip
    replacement.

161
Implant Prosthetic Complications
162
Problems with Screw Loosening
  • 1) Improper use of torque driver leading to
    inadequate preload force application
  • 2) Stripped screw driver or screw head
  • 3) Use of lab screws versus definitive screws
  • 4) Material and surface used for fabrication of
    screws
  • 5) Design of screws
  • Occlusal overload
  • Combination of any or all of the above

163
Implant Prosthetic Complications
164
Implant Prosthetic Complications
165
Treatment Options when presented with minimal
Interocclusal Distance
  • 1) Increase vertical dimension of occlusion for
    restorative convenience.
  • 2) Extract teeth involved that violated the
    interocclusal distance and replace accordingly.
  • 3) Orthodontic intrusion of opposing teeth
    involved.
  • 4) Coronoplasty, crown preparations,
    prophylactic endodontic therapy, periodontal
    crown lengthening options to restore teeth
    involved.

166
Treatment Options when presented with minimal
Interocclusal Distance
  • 5) Prior to surgical placement of implants,
    perform alveoloplasty of residual ridge to
    increase interocclusal distance.
  • 6) Prosthetic design screw retain as opposed to
    cement retain to implant level.
  • 7) Restorative material metal occlusal as
    opposed to porcelain fused to metal.

167
Lack of Inter Occlusal Clearance Treatment
Options
  • 1) Coronal adjustment of opposing arch or
    prophylactic endodontic therapy, crown
    lengthening and crowns to opposing arch.
  • 2) Alveloplasty prior to implant placement with
    deeper surgical implant placement.
  • 3) Prosthetically compensate with screw retained
    and metal occlusal to decrease required
    restorative clearance.

168
Implant Prosthetic Complications
169
Iatrogenic / Prosthetic
  • Need for Provisional Restorations
  • Positional stability
  • Occlusal function
  • Easily cleaned and maintenance of oral hygiene
  • Nonimpinging soft tissues
  • Strength and retention
  • Esthetics

170
Iatrogenic / Prosthetic
171
Removable Provisional
  • Acrylic RPD (flipper)
  • Need proper design for occlusal stops.
  • Adequate relief under pontic site or above
    grafted site upon occlusal pressure.
  • c) Permanent soft tissue reline material as
    occlusal force buffer.

172
Removable Provisional
  • Essix appliance (Acrylic removable overlay
    prosthesis)
  • a) Need proper design for occlusal stops.
  • b) Adequate relief under pontic site or above
    grafted site upon occlusal pressure.
  • c) Permanent soft tissue reline material as
    occlusal force buffer.

173
Removable Provisional
  • Hawley orthodontic retainer appliance
  • Need proper design of occlusal stops.
  • Adequate relief under pontic site or above
    grafted site upon occlusal pressure.
  • c) Permanent soft tissue reline material as
    occlusal force buffer.

174
Consequences of Peri-Implantitis
  • 1) May lead to eventual implant loss.
  • 2) Soft tissue exudates, abscess or infection
    localized to peri-implant locations.
  • 3) Guarded prognosis and continuous soft tissue
    maintenance requirement for peri- implant soft
    tissues.
  • 4) Possible source of irritation and discomfort
    to patient.

175
Possible Etiologies of Peri-Implantitis
  • 1) Location of Microgap
  • 2) Implant Thread Design
  • 3) Surgical Trauma
  • 4) Quality of bone
  • 5) Occlusal Forces
  • 6) Bacterial contamination
  • 7) Biologic width consideration
  • 8) Cement trap contamination
  • 9) Combination of any / or all of above

176
Peri-Implantitis-Definitions
  • Defined as an inflammatory process affecting the
    tissues around an osseointegrated implant in
    function, resulting in loss of supporting bone.

(Albrektsson Isidor 1994)
  • Plaque-induced progressive marginal bone loss
    observed on radiographs with clinical signs of
    infection of the peri- implant soft tissues.

(Cochrane Database of Systematic Reviews 2006)
177
Peri-implant Mucositis-Definitions
  • Defined as reversible inflammatory changes of the
    peri-implant soft tissues without any bone loss.

(Albrektsson Isidor 1994)
178
Prevalence Rates
  • Peri-implant Mucositis 8-44
  • Peri-Implantitis 1-19

179
Cement retained
  • 1) Ideal aesthetics.
  • 2) Questionable retrievability.
  • 3) Retention require conventional fixed
    prosthodontic principles of CHS of gt7.0 mm.
  • 4) Ideal Implant placement to support prosthesis
    with use of straight or angulated abutments.
  • 5) Ideal Occlusion or support over axially
    loaded ceramics.
  • 6) Less requirements for passivity or lab costs.
  • 7) Removal of cement subgingival may be
    compromised.
  • 8) Depth of implant level placement should allow
    ease of cement clean up.

180
Cement Problems
  • Subgingival cement left after cementation acting
    as a foreign body reaction causing pathologic
    bony and soft tissue reactions.

181
Dr. Mark Lins Cementation Technique
  • 1) Paint and coat OUTSIDE crown margins with
    Vaseline. Confirm lab provided 2 layers of die
    spacers on implant abutment or scanning of
    abutments.
  • 2) Light coat of cement of choice into implant
    crown restoration.
  • 3) Pump restoration Up and Down motion to
    release hydraulic pressure build in to allow
    thinning of cement layer.
  • 4) Removal after setting with curettes and
    floss.
  • 5) Soft tissue release may be required to
    confirm total removal of excess cement.
  • 6) Verification of seating of abutment and crown
    to implant platform level and cement removal.

182
Screw retained
  • 1) Compromised aesthetics.
  • 2) Reliable retrievability. (Multiple or full
    mouth reconstructions.)
  • 3) Retention achieved with minimal CHS of lt 7.0
    mm using screw retention preload principles.
  • 4) Accommodate compromised Implant placement to
    support prosthesis with use of custom or
    angulated abutments.
  • 5) Compromised Occlusion or support over axially
    loaded compromised integrity ceramics.
  • 6) More requirements for passivity or lab costs.
  • 7) No cement clean up considerations.
  • 8) Deep implant level placements.
  • 9) Transitional provisionals with multiple units.

183
Problems with Screw Loosening
  • 1) Improper use of torque driver leading to
    inadequate preload force application
  • 2) Stripped screw driver or screw head
  • 3) Use of lab screws versus definitive screws
  • 4) Material and surface used for fabrication of
    screws
  • 5) Design of screws
  • Occlusal overload
  • Combination of any or all of the above

184
Oral Hygiene
  • calculus build up can cause areas of soft tissue
    inflammation.
  • may result in progressive bone loss if left
    untreated.

Treatment
  • remove prostheses, check implants for mobility,
    retorque abutments.
  • perform maintenance cleaning on prosthesis and
    abutments.
  • reinsert prosthesis with new screws, give oral
    hygiene instructions.

185
Maintenance and Recall
  • Annually
  • periapical radiographs should be taken to monitor
    the crestal bone levels. (crestal bone can be at
    the level of the first thread in one year with
    0.1mm continued loss to approximately 1. 5 mm
    total bone loss)
  • remove and reinsert screw retained implant
    prostheses every 2 years unless indicated
    otherwise.
  • Replace prosthesis with new retaining screws if
    removed.
  • Cemented restorations are usually permanent
    (nonretrievable).
  • Recall focus
  • Occlusion - verify there are no excursive
    contacts. Should not hold shimstock. Better to
    be out of occlusion
  • Oral hygiene - same requirements as for natural
    teeth.
  • Soft tissue health - periodontal probing for
    evidence of disease.
  • Screw joint torque - check for loosened screws
    (most common problem).
  • Integrity of attachments - applies to overdenture
    / overpartials.
  • Stability of implants - must be stable (non
    mobile) to be successful

186
Maintenance and Recall
  • Screw retained prosthesis
  • Remove prosthetic retention screws
  • Screw access holes are usually sealed with a
    layer of cotton pellet, silicone plug or gutta
    percha the acrylic or composite resin.
  • Expose the screw by drilling carefully through
    the resin.
  • Remove the screw (slot or hex) with the
    appropriate screw driver.
  • Throat drapes are highly recommended.
  • Check for implant mobility and retorque abutments
    to 20 Ncm. (hand tighten as much as possible
    with finger abutment driver if no torque control
    device is available)
  • Clean and polish abutments (Do not remove)
  • Reseat restoration using new gold retaining
    screws.
  • Tighten screws as if doing nuts on the lugs of an
    automobile - place all screws back with minimal
    torque. Then work back and forth across the
    arch until all are tightened to 10 Ncm. (hand
    torque with appropriate hand screw driver if no
    torque controller is available)

187
Maintenance and Recall
  • Screw retained prosthesis (cont.)
  • Temporary reinsertion
  • fill access holes with small cotton pellet and
    polyvinylsiloxane impression material or putty.
  • Long-term reinsertion
  • fill access hole with small cotton pellet over
    the head of the screw, followed by warm gutta
    percha and only 1-2 mm of acrylic or composite
    resin.
  • Cemented restorations
  • Single unit
  • usually nonretrievable and not removed for
    maintenance.
  • Multiple unit (usually not indicated)
  • carefully tap off with crown remover, check for
    mobile implants and retorque abutment screws.
  • Replace restoration with provisional luting
    media, and recheck occlusion.

188
Hygiene Aids
  • Super - floss
  • End tufted brushes
  • Proxy brushes
  • Tarter control dentrifices
  • Mechanical instruments
  • Peridex

189
Incidence Rate Of Mechanical Complications
  • OD loss of retention or adjustments 30
  • Resin acrylic veneer facture of FPD 22
  • OD relines required 19
  • OD clip / attachment fractures 17
  • Prosthesis screw loosening 7
  • Abutment screw loosening 6

190
Implant Prosthetic Complications
191
Implant Prosthetic Complications
192
Implant Prosthetic Complications
193
Implant Prosthetic Complications
194
Implant Prosthetic Complications
195
Problems with Screw Loosening
  • 1) Improper use of torque driver leading to
    inadequate preload force application
  • 2) Stripped screw driver or screw head
  • 3) Use of lab screws versus definitive screws
  • 4) Material and surface used for fabrication of
    screws
  • 5) Design of screws
  • Occlusal overload
  • Combination of any or all of the above

196
Implant Prosthetic Complications
197
Implant Prosthetic Complications
198
Implant Prosthetic Complications
199
Implant Prosthetic Complications
200
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201
Problems in the field
  • Fractured/loosened screws
  • Fixture loss
  • Poor oral hygiene
  • Soft tissue reactions
  • Broken attachments
  • Fractured components

202
Problems in the field
  • Fractured/loosened screws
  • Fixture loss
  • Poor oral hygiene
  • Soft tissue reactions
  • Broken attachments
  • Fractured components

203
Fractured or loosened screws
  • Usually results in localized inflammation, loose
    restorations and discomfort.
  • First suspicion when patient complains of
    discomfort or loose implant.
  • Prosthetic gold retaining screws have either a
    slot or hex head.
  • Abutment screws require a hex abutment driver,
    large slot, hex or square driver.
  • Standard and conical (estheticone) abutments have
    a raised hex and require a wrench that fits over
    this hex.
  • All other abutment screws have the slot, hex or
    square depression inside the screw head.
  • Loose single tooth abutments are true
    emergencies. Continued rotation can risk
    rounding the corners of the hex on the implant,
    causing a loss in anti-rotation.

204
Fixture loss(Must differentiate between
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