this presentation will help u understand placemant of implants after radaition for cancer patients

1. Implants In
Irradiated
Jaw
DR ZUBAIR AHMAD
PGR OMFS KEMU/MAYO
HOSPITAL LAHORE

2. Head And Neck Cancers
 Worldwide 9th most common cancer GLOBAL CANCER STATISTICS 2012
 Cancers of the lip and oral cavity are highly frequent in Southern Asia as well as
the Pacific Islands (with the highest incidence rate worldwide in both sexes), and it
is also the leading cause of cancer death among men in India and Sri Lanka GLOBAL
CANCER STATISTICS 2018

3. Goals Of Cancer Surgery
 To remove cancerous tissue
 Obtain locoregional control
 Increase survival (5 year survival for HNC is 62%)

4. Importance of Oral Rehabilitation
 Resection from surgical treatment most often results in changes in speech,
mastication, swallowing, as well as anatomic changes and deformities such as
tissue loss.
 These changes eventually hinder conventional prosthetic rehabilitation
 Studies on quality of life demonstrate that patients attach importance to chewing,
swallowing and speech and become depressed if these issues are not addressed
 Dental rehabilitation should be an integral part of overall surgical objective of
reconstruction after cancer ablation

5. Goals Of Rehabilitation
Aesthetic
Contour
Expression
Competence
Functional
Speech
Mastication
Swallowing

6. Prosthetic Rehabilitation Challenges
 Reduced bony support
 Lack of vestibular depth
 Altered tongue movement and anatomy
 Thick, non-pliable soft tissue flaps that
have been grafted from distant areas and
are not adherent to underlying bone
 Limited mouth opening
 Xerostomia

7. Advantages Of Implant Supported
Prosthesis
 Maintain bone
 Restore and maintain occlusal
vertical dimension
 Maintain facial esthetics
(muscle tone)
 Improve esthetics
 Improve phonetics
 Improve occlusion
 Improve/regain oral
proprioception
 Increase prosthesis success

8. Advantages Of Implant Supported
Prosthesis
 Improve masticatory performance
 Reduce size of prosthesis (eliminate palate, flanges)
 Provide fixed versus removable prostheses
 Improve stability and retention of removable prostheses
 Increase survival times of prostheses
 No need to alter adjacent teeth
 More permanent replacement
 Improve psychological health

9. Radiotherapy
 Previously radiotherapy was an absolute contraindication for implants during the
1970s-80s
 But now according to recent studies implants success rates in non-irradiated jaw is
95%
 And implant success rate in irradiated jaws is 8-86%

10. Radiotherapy
 The mainstay of treatment for oral cavity cancer is surgery along with neo-
adjuvant and adjuvant chemo/radio therapy as required
 Typically, 2-Gy fractions are given according to standard fractionation therapy
(given once a day) or hyperfractioned therapy (given twice a day) for a delineated
time period.
 Daily fractions can be given every day for 25 days or for 5 days per week for a 5-
to 7-week period.

12. Radiotherapy

13. Fractionation
 A tumour will contain thousands of cancer cells
 At a given time not every cell will be in their M phase
 We distribute damage by breaking up the total dose of radiation
 This is called Fractionation
 Also helps normal cells to recover. Normal cells heal better than cancer cells

14. Radiotherapy Complications
 Acute & Chronic
 Depends upon total dosage and duration of therapy
Early Radiation Effects Late radiation Effects
Mucositis Dysphagia
Taste and smell loss Trismus
Hyposalivation Osteoradionecrosis
Radiation Myelitis

15. Effects Of Radiotherapy On Osseous
Tissue
 Post-radiation alterations of the bone matrix develop slowly, the initial changes being a
result from an injury to the bone remodeling system, i.e., osteoblasts, osteocytes and
osteoclasts.
 Osteoblasts tend to be more sensitive than osteoclasts, therefore an increase in the
cellular lysis may occur
 As a result, the process of bone matrix formation stops, hindering the mineralization
process, which may lead to a spontaneous bone fractures and osteoradionecrosis
 Endothelial cells also are heavily affected, and the vascular fibrosis results in a decrease
in the vascularization, affecting the bone and medullary cells vitality, so the area
remains susceptible to infection and necrosis, even after a small trauma
 With time, the bone marrow exhibits marked acellularity and avascularity, with marked
fibrosis and fatty degeneration.

16. Failure To Osteointegrate
 Radiation related Factors
 Implant related Factors

17. Factors Affecting Osseointegration
 Time from Radiotherapy to Implant Surgery
 Irradiation Dose
 Type of Irradiation Source; Fractionation
 Adjuvant Chemotherapy
 Bone bed, Grafted Bone

18. Timing Of Implant Placement
The Influence of Radiation Therapy on
Dental Implantology. Anderson et al.
Implant Dentistry, 2013; (22)1

19. Pre-Radiation Implant Placement
At the time of Cancer Ablation and Primary Reconstruction

20. Post-Radiation Implant Placement
Secondary Reconstruction
 Delayed implants placement enables assessment of the postsurgical status of the
patients (both functionally and psychologically), and more accurate cancer
prognosis.
 The first 12 months after tumor therapy is generally considered to be the high risk
period of recurrence.

21. Irradiation Dose

22. Irradiation Dose
The Influence of Radiation Therapy on
Dental Implantology. Anderson et al.
Implant Dentistry, 2013; (22)1

23. Adjuvant Chemotherapy
 Concomitant chemotherapy is often incorporated in cancer therapy to augment
the anti-tumor effect of RT.
 Major side effects include acute mucositis and altered taste, which can be
multiplied with RT.
 It seemed as if chemotherapy in longer-term perspective has a negative effect on
osseointegration, comparable to irradiation

24. Bone bed, Grafted bone
 Grafted bone that will replace bone in an irradiation field will act more like the
non-irradiated bone.

25. Failure to Osseointegrate
 Radiation related Factors
 Implant related Factors

26. Implant Factors Affecting
Osseointegration
 Length
 Implant Design and Surface
 Anatomical Site of Placement
 Prosthesis Design
 Loading Period

27. Implant Length / Diameter
 Goto et al observed a greater number of failures in short implants, recommending
caution in the use of these implants in irradiated patients.
 Goto M, Jin-Nouchi S, Ihara K, Katsuki T. Longitudinal follow-up of osseointegrated implants in patients with resected jaws.
Int J Oral Maxillofac Implants 2002;17:225-30
 It is thus recommended to use the longest/widest possible implants to optimize
bicortical anchorage.

28. Implant Length / Diameter

29. Implant Design & Surface
 “….machined implants tended to fail 2.9 times more than the implants with
surface treatment…” Buddula A, Assad DA, Salinas TJ, Garces YI, Volz JE, Weaver AL. J Prosthet Dent 2011;106:290-6.
Survival of turned and roughened dental implants in irradiated head and neck cancer patients: a retrospective analysis.
 The properties of the implant surfaces, such as topography and chemical
treatment, are very important factors.
 In addition to providing greater contact between the bone and the implant,
especially in areas of less corticalized bone tissue, which favors biological
responses that accelerate the osseointegration process, surface treatments also
increase mechanical strength and reduce corrosion

30. Anatomical Site of Placement
 Dental Implant survival rate for Maxilla: 78.9%
 Dental Implant survival rate for Mandible: 93.3%
 Dental Implant survival rate for Free Flaps: 89.3%
 Dental Implant survival rate for grafted bone: 81.7%
Dental Implant Survival in Irradiated Oral Cancer Patients; A Systematic Review of the Literature Nooh et al, 2013. Int J Oral
Maxillofac Implants

31. Implant Prosthesis
 Because of the oral effects of
radiotherapy, an implant
supported prosthesis (FP-1,
FP-2, FP-3) is recommended
over a soft tissue prosthesis
(RP-4, RP-5).
 This will reduce the possible
soft tissue irritation that is
associated with post
radiotherapy patients
wearing removable
prostheses.

32. FP1

33. FP2

34. FP3

36. RP4

37. RP5

38. Loading Period
 Branemark et al advocated an unloaded healing time of three to six months. This
is in contrast to the implant loading protocols, progressive loading and
immediate loading.
 Abutment connection, fabrication and loading of the prosthesis should be
delayed for six months instead of the traditional three to four months to permit
osseointegration.

39. Complications

40. Osteoradionecrosis
 Osteoradionecrosis (ORN) is often defined as an area of exposed bone that
persists for at least 2 months in bone that has been irradiated. This definition may
be insufficient, as ORN can present radiographically as a pathologic fracture with
intact mucosa or skin.

42. Fibroatrophic
theory by
Delanian et al
1993

45.  HBOT is reported to increase oxygen gradient
between the irradiated tissue and the healthy
tissue and provokes capillary neo-
angiogenesis, thereby enhancing bone healing
and regeneration.
 According to the Marx protocol, HBOT involves
20 dives of HBO at 2 to 2.5 atm for 90 minutes
given prior to placement of dental implants and
10 dives postsurgery.
 There are no randomized, controlled, double-
blinded studies to prove that HBOT really has a
significant osseointegration stimulating effect
in irradiated patients.

46. Summary Of Recommendations
 Ideal time for implants is 6-24 months after radiotherapy.
 Know the type/dose of radiotherapy.
 HBOT if radiation dosage > 50Gy.
 Long, wide implants, rough surface to promote osseointegration.
 No provisional prosthesis.
 The osseointegration period is doubled.
 Limited use of vasoconstrictors during second stage surgery.
 Implant supported prosthesis. Minimal contact with mucosa. Minimal cantilevering.
 Regular follow-ups.

47. Thank you