PLACEMENT OF DENTAL IMPLANTS IN THE IRRADIATED MANDIBLE : A PROTOCOL INVOLVING ADJUNCTIVE HYPERBARIC OXYGEN

1. Placement of Dental Implants
in the
lrradiated Mandible: A Protocol
Involving
Adjunctive Hyperbaric Oxygen
NAMITHA AP
3RD MDS
DEPT.OF PROSTHODONTICS
Journal club presentation

2. Contents
Introduction
Protocol
Applications
Discussion
Conclusion
Related articles

3. INTRODUCTION
Surgical treatment
of head and neck
cancer
Defects that challenge conventional
prosthodontic rehabilitation
IMMOBILE
SCARRED
TISSUE
LOSS OF
VESTIBULAR
DEPTH
LOSS OF
TEETH
LOSS OF
BONY
SUPPORT
significant difficulty in
retention and function
of the conventional tissue-
supported prosthesis
Mucositis and
xerostomia
associated with
irradiation
compromise
prosthesis and
predispose
patient to
osteoradionecrosis
?
Endosseous
implants

4. Endosseous implants in irradiated
patients
 Even minor surgical intervention in patients who had received head and
neck irradiation has been associated with decreased healing and
development of osteoradionecrosis
 Most surgeons have empirically excluded implants as an option when the
surgical field has received greater than 5,000 cGy of irradiation.
osteoradionecrosis, apathologic
fracture of the mandible and
subsequently the mandible was
resected.
patient received 6600 cGy for a
squamous carcinoma of the lateral
tongue. Three years later implants
were placed.
After three years - an
infection associated
with left posterior
implant

5. Purpose
 The purpose of this article is to present a protocol for successful
rehabilitation of the irradiated patient using an implant-suported prosthesis.
 An integral component of this protocol is the use of hyperbaric oxygen.

6. Rationale for Use of
Hyperbaric Oxygen
 Some of the earliest clinical experiences with implants placed into
irradiated patients have been with those implants placed for maxillofacial
prostheses and obturators.
 The success rate of implants placed in this situation has been
disappointingly low.

7. HYPOXIC
HYPOCELLULAR
HYPOVASCULAR
Doses of
tumorocidal
irradiation
greater than
5,000
cGy
Tissue bed that
exhibits poor
wound healing
In Bone -
osteoradionecrosis
HBO
beneficial
effect
on
osteogenesis
STIMULATION
OF CAPILLARY
INGROWTH
COLLAGEN
SYNTHESIS
FIBROBLASTIC
PROLIFERATION
CAPILLARY
ANGIOGENESIS

8.  Clinical studies have shown the
efficacy of HBO for the
prevention and treatment of
osteoradionecrosis in irradiated
patients.
 The same hyperbaric protocol
significantly decreased the
morbidity associated with non
vascularized bone graft
reconstruction of surgical defects
in irradiated head and neck
cancer patients
• Trancient elevation of partial
pressure of oxygen
ISOLATED TREATMENTS
• Measurable, sustained increase in
oxygeneation of hypoxic tissue
8-10 treatments
• plateaus at 80% to 85% of normal
tissue p0 ( relatively permanent
increase)
20 th treatment

9. Clinical trials
 overall success of extraoral implants placed
within irradiated bone was only 57.9%(us) and
64.7% (Sweden) compared with success in
nonirradiated patients of 97.4% and 94.4%.
 In the irradiated group, the failure of implants
was progressive and continued for a longer
period.
 Unlike implants placed into normal bone, where
failure levels off at approximately 18 months,
implants in irradiated bone have been reported
to show progressive loss for up to 6 years after
placement.
• show inconsistent success,
with failure as high as 45%
maxillae
• failure rates of implants
placed into bone that has
been irradiated with
greater than 5,000 cGy
have been reported as
high as 33%.
mandible

10. PROTOCOL
 To prevent the physical, psychological, and economic cost associated with
failure of an implant-supported prosthesis
 They have successfully placed and restored 28 mandibular implants in five
patients.
 All patients received greater than 5,000 cGy to the implant site and have
been followed for 1 to 5 years with no implant failures.

11. 1. Delay implant surgery
until 6 months after
irradiation
2. Thorough informed
consent
3. Cessation of smoking
4. Perioperative
Hyperbaric oxygen
5. Increase integration
time by 3 months
6.
Overengineered/implant-
supported prosthesis
7. Strict oral hygiene
regimen
Protocol for Implant
Placement in the
Irradiated Patient

12. Timing of implant placement
 some studies indicate a progressive decrease in tissue
oxygenation and vascularity relative to time after irradiation
other studies have shown that, several months after
irradiation, there is an increase in vascularity and an
improvement in bone healing.
Acute phase after
surgery and
radiation
Identification and
treatment of recurrent
disease
Restoration of
systemic health
wait a minimum
of 6 months
after irradiation
before implant
placement

13. Informed consent
 no prospective randomized studies that adequately
document the expected long-term success of implants
placed in these situations.
 The potential morbidity and cost associated with implant
failure or osteoradionecrosis therefore require careful
informed consent.

14. Decreased micro
vascularity
compromised
wound healing
Cessation of smoking
 In otherwise non compromised
patients, smoking is associated with a
significant decrease in initial successful
osseointegration of implants as well as
with increased failure of implants once
they are restored.
 The risk that continued smoking may
add to the already compromised
healing of an irradiated patient has
excluded these patients who do not
wish to stop from implant placement

15. Perioperative hyperbaric oxygen
 A regimen of 20 preoperative treatments consisting of
100% oxygen at 2.4 atmospheres for 90 minutes is used
 Patients receive an additional 10 treatments after
surgery, for a total of 30 perioperative treatments.

16. Atraumatic surgical technique
 Aggressive soft tissue reflection will decrease the blood supply to the
surrounding bone, particularly in older patients whose primary blood supply
is from the overlying periosteum.
 In irradiated patients, wide reflection of periosteum is associated with
development of osteoradionecrosis.
 The incision for implant placement in the irradiated patient should be
planned to allow direct access to the implant site with minimal further
periosteal reflection

17. Increased integration time
 The time required for integration is increased for implants placed within
irradiated bone.
 There is decreased bone regeneration adjacent to the implant, in an
irradiated site.
 To improve the quantity of bone growth around the implants.
 Extended the integration time by 3 months.
 The length of time between implant placement and uncovering is 6 months
in the mandible and 9 months in the maxilla.

18. Overengineered/entirely implant-
supported prosthesis
 Avoid the potential for trauma from a tissue-borne
prosthesis by designing an entirely implant-supported
hybrid- type prosthesis.
 There is increased chance of loss of the implants, and,
overall, less bone support for individual implants is
expected
 If a microvascular graft has been placed, the
implant/prosthetic unit is often required to resist the
forces resulting from an increased crown-to root ratio
and the cantilever effect that are not present in a
typical hybrid prosthesis in the noncancer patient
Poorly fitting
dental
prosthesis
Osteoradionecrosis

19. METICULOUS ORAL HYGIENE REGIMEN
 Periodontal tissues are compromised as a result of irradiation
therapy, and bacterial resistance is reduced by the resulting
xerostomia.
 Bone surrounding teeth or implants is less resistant to the effects of
these bacteria.
 Meticulous oral hygiene is needed around the implant supported
prosthesis, and frequent follow-up by the dentist is necessary until it
is established that the patient is able to accomplish this.

20. APPLICATION TO SPECIFIC CLINICAL SITUATIONS
1.Implants in the irradiated mandible
 Intact, edentulous mandible - begin treatment planning 4 months
after completion of irradiation therapy.
 Five months after irradiation, patients begin an HBO regimen
consisting of 20 treatments at 2.4 atmospheres for 90 minutes.
 Implants are placed after the 20th treatment
 Patients then receive an additional 10 treatments (to facilitate
wound healing and decrease dehiscence)
 Six months after implant placement, they are uncovered.
 As a result of the cumulative and permanent improvement in
wound healing resulting from the initial hyperbaric treatment, no
further hyperbaric therapy is used at this time, or for other
adjunctive procedures should they become necessary.

21. 2. Implants in irradiated maxillae
 A similar protocol should be followed as previously described for the
mandible.
 Integration times for maxillary implants are typically longer, even in
the non irradiated patient.
 Therefore, we have empirically increased integration time from 6 to
9 months in the irradiated maxilla.

22. 3.Implants in microvascular free flaps
 Surgical ablation of large tumors often results in discontinuity
of the mandible.
 When the surgeon’s preference and defect size and location
result in plans for immediate reconstruction at the time of the
initial tumor surgery, a microvascular free graft is often used.
 In this situation, implants are not placed at the time of the
initial reconstruction, but rather after irradiation, in
conjunction with HBO treatment.
 Twenty treatments are delivered before implant placement
and an additional 10 treatments after surgery.

23. RATIONALE
Bone formation is decreased
around integrating implants
exposed to irradiation.
Osteoradionecrosis has
been associated with bone
plates and implants placed
into the native mandible
adjacent to microvascular
grafts that are subsequently
irradiated.
Implants placed at the time
of the initial reconstruction
may go unrestored because
of failure of integration,
placement in an unusable
position, recurrent cancer,
and death of the patient
Hyperbaric oxygen
treatments instituted 5
months after irradiation can
improve wound healing and
integration and decrease
complications

24. 4.Irradiation of previously integrated
implants
 With the large number of patients currently restored with osseointegrated
implants, primary and recurrent cancers will likely lead to a number of these
patients requiring irradiation.
 In this situation, periimplant complications are common, and a 27%
incidence of osteoradionecrosis has been reported.
 These implants be buried before irradiation and that a course of 20 HBO
treatments be instituted before uncovering after irradiation.

25. CONCLUSION
 Consistent success is possible when a systematic protocol that includes HBO
is used.
 In light of the improved predictability, HBO should be considered as an
adjunctive treatment when implants are placed into sites that have been
exposed to greater than 5,000 cGy, especially when clinical signs of
irradiation injury exist.

26. Related articles
 to study whether osseointegration of implants in irradiated tissues is subject to a higher
failure rate than in non irradiated tissues.
 It further aimed to study whether hyperbaric oxygen treatment (HBO) can be used to
reduce implant failure.

27. 78 patients
47 men
31 women
Mean age was 64.9
years (range, 23 to 94)
Fourteen patients died
during the study,
resulting in a
mortality rate of 17.9%.
78 patients
47- orbit
defects
16-
temporal
defects
9- nose
defects
8- maxillary
defects
3 –
mandibular
defects
335 endosseous implants –
installed
without bone grafting or
covering with expanded PTFE
membranes
In the irradiated groups
implants were inserted in the
tumor cavity and thus in the
radiation field
99 were lost during
follow-up, for a total
loss rate of 29.5%.

28. Implant stability checked -
Clinical inspection and radiographic investigation Implant loss and adverse soft tissue reactions registered
Post operative follow up
Initially at 3 months interval After 1 year 6 months interval
Irradiation therapy – Cobalt 60 radiation
Dosage, fractionation, radiation fields, and timing from irradiation to surgery were calculated
Patient’s charts investigated w.r to.
Tumor type and stage Presence of local nodes Type of tumor treatment
Timimg and region of implant
installation
78 cancer patients
Rehabilitation – osseintegrated implants 1981-1997

29. a. Irradiated before
implant surgery
147 endosseous implants
79 were lost - 53.7%
b.Non irradiated
89 endosseous implants
12 were lost -13.5%
c.Irradiated patients who
had undergone
hyperbaric oxygen
therapy – HBO before
implant surgery
99 endosseous implant
8 were lost - 8.1%
d. Ten previously
irradiated patients who
had implant installed and
later lost most of them
were treated with HBO
43 endosseous
34 were lost - 79.0%
Seven
patients died in this
group (mortality
rate, 21.8%)
Four patients died in
this group
(mortality rate,
15.4%)
Three patients died
in this
group (mortality
rate, 15%).
One patient died in
this
group (mortality
rate, 10%).

31. Conclusions
1)irradiation causes significant changes in the host
bone bed that reduce the potential for
osseointegration, thus increasing implant loss
2)Adjunctive HBO treatment can improve
osseointegration.

32.  This report presents the preliminary results of placing 18 titanium screw
implants into previously irradiated mandibles in conjunction with hyperbaric
oxygen therapy.
 Four patients who had previously received cancericidal radiation therapy
to the mandible received titanium endosseous screw implants for
prosthodontic rehabilitation.
 The patients' (three female and one male) ages ranged from 16 to 66
years.
 Each patient and his or her family members were counseled on possible
complications of surgical involvement to the irradiated mandible.

33.  The time from the end of
radiation therapy to implant
placement ranged from 1.25
years to 11 years and 11
months, with a mean of 4.25
years.
 Each patient underwent HBO
therapy before and after
implant placement.
 This therapy involved 20
preoperative HBO treatments
followed by implant
placement, then 10
postoperative HBO treatments.
 Each HBO treatment consisted
of breathing 100% oxygen for
90 minutes at approximately 2.4
atm

34. 18 implants
In one patient one
implant (6%) was judged
non osseointegrated at
the abutment connection
and was removed.
In a second patient one
implant (6%) was judged
osseointegrated but did
not receive an abutment
and was "put to sleep."
The remaining 16 (88%)
implants received
abutments and were
used for prosthetic
rehabilitation.
Mandible of 4 patients
17 (94%) were judged
osseointegrated at the
abutment connection

35.  The time between
implant placement and
abutment connection -
4 to 11 months (mean 7
months).
 After abutment
connection, each
patient underwent
prosthetic rehabilitation
with the implants.
 Follow-up ranged from 1
year to 5 years, 1 month,
with a mean of 3 years,
1 month.
Clinically
immobile
No radiographic
evidence of
periimplant
radiolucency
Did not cause
persistent pain
or infection
Successful osseointegration

36. • Implant-retained and supported fixed mandibular prosthesis and a
maxillary complete denture.
• no dietary limitations or complaints concerning the use of her
prosthesis
Patient 1
• Implant-retained, mucosal-supported mandibular prosthesis and a
maxillary complete denture
• no dietary limitations but does not use her maxillary prostheses.
Patient 2
• Implant retained and supported fixed mandibular prosthesis and
maxillary complete denture
• No complaints about the use of her prostheses, but she reported the
need for a modified diet because of poor food control with her
residual tongue.
Patient 3

37. one implant did not receive an abutment
because of the position and angulation of the
implant(did not alter the prosthodontic
treatment or result)
Because of previous ablative procedures,
moderate deviation of her mandible toward
the defect occurred.
occlusally compensated for
with an inclined plane on the opposing complete
denture

38. Patient 4
 received an implant-retained and supported fixed mandibular prosthesis
and a maxillary complete denture.
 The mandibular prosthesis was connected to two implants in the right
residual and two implants in the left residual irradiated mandible.
 This prosthesis was further supported by four implants placed in a
nonirradiated scapula osseocutaneous microvascularized free flap
 This patient reported an unlimited diet with some tongue-related food
control problems.
 difficulties in adapting to the altered sensual perceptions associated with
his reconstructed anterior mandible and implant prosthesis.

39. Discussion
 During the surgical phase of implant treatment, minimal elevation of the
periosteum was performed in the implant receptor site to minimize
perfusion disruption to the underlying bone.
 During each step of implant site preparation, the surgical procedure was
continued if bleeding bone was encountered.
 If no bleeding occurred, the procedure at that site was stopped.
 This evaluation process was carried out following guide drill preparation,
twist drill preparations, pilot drill preparation, and threading of the implant
site.
 In this patient population, no implant site was abandoned because of a
perceived lack of bony bleeding.

40.  Prosthodontic results with edentulous patients with mandibular resection are
often less than optimal because of toss of supporting structures, altered
neuromuscular control, and prosthesis instability
 With this patient implants compensated for anatomic deficiencies, providing a
foundation on which a stable prosthesis could be fabricated
 After implant site preparation for patient 2, bleeding was less at one site than at
the other three.
 At the site with less bleeding the implant was judged to be non osseointegrated
at the abutment connection.
 After the removal of this implant bleeding was noted within the prepared site.
 Soft tissue was closed over this area, and healing occurred without
complications.
 Long-term vascular changes associated with cancericidal radiation treatment
may be an argument for placing implants in bone shortly after radiotherapy.
 The implant that failed to obtain osseointegration was in the patient with the
longest interval between completion of radiotherapy and implantation

41.  Patient 2 suffered from severe xerostomia, which reduced the retentive
quality of her maxillary complete denture.
 Although salivary substitute improved retention, the patient preferred to not
wear the prosthesis.
 Osteoradionecrosis of the jaws is debilitating, deforming, and costly; it often
leads to narcotic addiction and should be prevented if possible.
 The incidence for treatment of osteoradionecrosis in the mandible requiting
resection may be as high as 73%.

42. Expense of HBO therapy
 Average cost for 1 year of treatment without HBO therapy was $31,000,
and the average total cost was $102,000.
 The average cost for 1 year of treatment with HBO therapy was $20,000,
and the average total cost was $82,000
 The average cost of a single HBO treatment has been reported at $150.
 At this rate the HBO protocol used in this report would add $4500 to the cost
of the prosthodontic rehabilitation

43. Conclusion
 It has been cstimatcd that 65% of osteoradionecrosis results from surgical
trauma or the use of dental prostheses.
 The use of implants in irradiated tissues may provide a means of enhancing
prosthetic rehabilitation while reducing the risk of tissue trauma, which may
develop into osteoradionecrosis.
 Considerable knowledge exists regarding the adverse effects of radiotherapy,
the benefits of HBO therapy, and the success of titanium implants.
 However, little specific information has been reported about the efficacy of
combined HBO therapy and implant therapy in previously irradiated mandibles.
 The number of patients and implants in this report is too small to suggest a strong
relation between HBO therapy and its effect on implant osseointegration in
previously irradiated mandibles.

44.  Objective of this prospective study was to assess the effect of HBO therapy
on treatment outcome (condition of peri-implant tissues, implant survival,
oral functioning and quality of life) of prosthodontic rehabilitation with
implant-retained lower dentures in irradiated head neck cancer patients.

45. Materials and methods
 In 2000 all consecutive edentulous patients that
had been treated for a first malignancy in the
head and neck region (squamous cell
carcinoma of tongue, floor of the mouth,
mandibular gingiva, buccal mucosa or
oropharynx) with either radiotherapy or a
combination of surgery and radiotherapy were
screened to be included in this study.
 Patients who agreed with treatment were
randomized in two groups.
 These patients either received peri-operative
antibiotics or antibiotics in combination with
HBO treatment
72 patients were
screened
48 had problems
in their lower
denture
26 patients
wanted to
participate in this
study

46. Treatment
 All patients underwent both tumour
surgery and radiotherapy
 Dosimetry was performed to
calculate the dose at the implant
locations.
 The cumulative absorbed dose was
calculated using the CT data
available for the treatment
planning.
 The anterior part of the mandible
was drawn as region of interest
 The maximum dose in the region of
interest was used as the cumulative
absorbed dose in that region

47. •received perioperative antimicrobial prophylaxis with broad-
spectrum antibiotics (cefradine 1 g, three times daily during 2
weeks).
GROUP 1 – 13 PATIENTS
•13 patients (group 2) received 20 HBO treatments of 100% oxygen
at 2.5 atmospheres for 80 min (4 periods of 20 min) before implant
surgery, and 10 HBO treatments of 100% oxygen at 2.5
atmospheres for 80 min after implant surgery in addition to the
antimicrobial prophylaxis as applied in the non-HBO group
GROUP II – 13 PATIENTS
After randomization with regard to age, gender, site and stage of the primary
tumour, reconstructive procedure and total dose of irradiation
All patients started with broad-spectrum antibiotics 1 day before implant surgery and
continued for 2 weeks

48.  In all patients the implants were placed in the interforaminal region of the
mandible as a one-stage surgical procedure by the same surgeon (GM).
 The most lateral implants were placed at least 5 mm medially of the mental
foramen and there was an equal distance between the implants.
 After an osseointegration period of six months, fabrication of implant-
retained prostheses was started according to standard clinical and
laboratory procedures.
 A new maxillary complete denture and a mandibular overdenture
supported by an individual made bar-clip construction were fabricated.

49. Clinical assessments
 The clinical assessment included dental status, oral
condition and prosthetic rehabilitation.
 Postoperative complications and implant survival were
recorded from the time of surgery until 1 year after
placement of the prostheses.
 Periodontal indices were assessed six weeks after
placing the new dentures (T1) and 12 months later (T2).
 The periodontal indices included the following
parameters: plaque index, bleeding index, gingival
index, probing depth, and implant mobility.

50. Radiographic analysis
 The oblique lateral radiographic technique was used to determine
resorption patterns of the edentulous mandible and to study bone
(re)modeling processes following the placement of dental implants.
 At the start of prosthetic loading (T1) and after 12 months (T2), four oblique
lateral radiographs were made to depict the lateral and frontal parts of the
mandible.
 The mesial/distal bone height was defined as the distance between the
apex of the implant and the marginal bone level at the mesial/distal side of
the implant.

51. Functional assessment and quality of
life
 Preoperatively the patients (T0) were asked to fill out questionnaires
regarding oral functioning and quality of life.
 Similar questionnaires had to be completed six weeks (T1) and 12 months
(T2) after placing the new dentures.
 assessed using the core questionnaire (EORTC QLQ-C30) and the head and
neck module (EORTC H&N35) of the European Organization for Research
and Treatment of Cancer (EORTC).
 The core questionnaire consisted of 30 questions (items) exploring six multi-
item functional scales (physical function, role function, social function,
emotional function, cognitive function, and overall health status/QoL),
three multi-item symptom scales (pain, fatigue and emesis) and six single
items (bowel function, breathing, appetite, sleep disorders and economic
sequelae.

52.  The head and neck module contained 35 items exploring symptoms and side
effects of treatment.
 It comprised six multi-item scales (pain, swallowing, senses, speech, social
eating, social contact, sexuality) and seven single items
 All scores ranged from 0 to 100.
 With regard to the functional scales of the EORTC QLQ-C30, higher scores
meant higher QoL and better results.
 In the symptom scales and the single-item scales of the EORTC QLQ-C30, higher
levels represent higher degrees of problems caused by the symptom, so that
the best result in these scales was a score of 0.
 The scores of the H&N module finally also have a range from 0 to 100 with
higher scores representing higher degrees of problems and good results
showing low scores.

53.  The physical, psychological and social impact of oral disorders was
assessed using the Oral Health Impact Profile(OHIP) questionnaire
comprising of six multi-item scales.
 Responses on each item ranged from ‘very often’ (score 4) to ‘never’
(score 0). Adding the scores results in a total score per scale; a high score
means a high impact on the aspect concerned.
 The six OHIP scales assessed were functional limitation (9 items, range 0–36),
physical pain (9 items, range 0–36), physical disability (9 items, range 0–36),
psychological discomfort (5 items, range 0–20), psychological disability (6
items, range 0–24) and social disability (5 items, range 0–20).
 In addition the OHIP-14 (14 items, range 0–56), a short form of the original
OHIP- measuring the overall-impact of dental problems, was used.

54. ASSESSMENT OF DENTURE SATISFACTION
 A validated questionnaire consisting of eight separate items focusing on
the function of upper and lower dentures, and on specific features such as
esthetics, retention and functional comfort.
 Each item was presented with a five point rating scale on which the patient
indicated the extent he or she was (dis)satisfied.
 Overall denture satisfaction was expressed on a 10-point rating scale (0–
10), ‘0’ being completely dissatisfied, ‘10’ being completely satisfied.

55. SUBJECTIVE CHEWING
ABILITY
 Assessed by using a 9-item
questionnaire on which the
patient could rate on a 3-point
scale her/his ability to chew
different kinds of food.
IMPACT OF DENTURE
PROBLEMS IN SOCIAL
ACTIVITIES
 assessed with the Groningen
Activity Restriction Scale Dentistry
(GARS-D).50 GARS-D is an 11-item
scale yielding a score ranging
from 0 to 22; the higher the score,
the larger the impact on social
activities.

56. .
26
PATIENTS
17 MEN 9 WOMEN
RANGE 47-
77 YEARS
mean age
60.1 ± 7.5
years
The interforaminal area of the lower jaw in which
the implants were inserted received a
cumulative radiation dose of at least 46 Gy
(mean 61.4 ± 12.9 Gy, range 46–116 Gy) at the
implant site.
2 patients past
away during the
osseointegration
23 patients
implant-retained
overdentures
were fabricated
1 patient no
prosthesis – loss of
implants d/t ORN
At the 1 year evaluation,
six patients were lost to
follow-up due to serious
illness not related to
implant surgery

57. Clinical assessments
All patients receiving HBO therapy were
able to fulfill the complete treatment
without problems.
(interforaminal bone volume was sufficient
to enable reliable placement of implants)
LOST
IMPLANTS
TOTAL
IMPLANTS
PLACED
103
11
8- BEFORE
LOADING
3- AFTER
LOADING

58.  The difference
between the
groups was not
significant.
Moreover, loss of
implants was not
related to the
time interval
between
radiotherapy
and placement
of implants.
in two patients
treated without
HBO three implants
were lost (implant
survival rate 93.9%)
At the one-year evaluation
In five patients
treated with HBO
eight implants were
lost (implant survival
rate of 85.2%).

59.  No significant difference was
found in percentage of
successful dentures on
implants between the both
groups, neither existed a
correlation between the
reconstructive procedures
irradiation dose, implant
survival and success of the
denture.
 Osteoradionecrosis
developed in one patient in
the HBO group.
There was no significant difference in peri-implant
health between both groups except for plaque-
index at the 1-year interval
peri-implant parameters were low at all evaluation
periods and did not change significantly over time,
except for pocketdepth in the HBO group where a
significant increase was observed.

60. Radiographic evaluation
 During the first year after loading a minor, although significant, peri-implant
bone loss of 0.7 ± 0.6 mm was observed at all implant sites (0.6 ± 0.6 mm
and 0.7 ± 0.7 mm at the HBO and non-HBO sites, respectively).
 No significant difference in peri-implant bone loss was observed between
the HBO and non-HBO patients

61. Quality of life
 All functional scales of the EORTC QLQ-C30
showed a strong tendency towards
improvement especially in the non-HBO
group, but only emotional functioning
improved significantly.
 The symptom scales and single items
showed no changes except for a
temporary increase on dyspnoea at T1 in
the HBO group and a decrease on pain at
T1 in the non-HBO group
 The items of the head and neck module
showed no significant changes.
 Also no improvement could be observed
from HBO therapy on dryness of the mouth.

62.  The results of the Oral Health Impact Profile questionnaire showed a
beneficial effect of the treatment on psychological discomfort and strong
tendencies towards improvement on all other scales especially in the non-
HBO group.

63. Functional assessments and denture
satisfaction
 showed significant improvement in time, but no differences between the
HBO and non-HBO group were seen.
 The impact of denture problems on social activities, as assessed with the
GARS-D, and the ability to chew different kind of foods showed tendencies
towards improvement for both groups

64. Conclusions
 Radiotherapy should not be considered an absolute contraindication for
implant therapy in the mandible.
 HBO therapy does not influence the failure rate of implants inserted in
mandibles when compared to patients treated without HBO therapy.
 The study sample was too small to make such a firm conclusion against a
potential benefit of HBO therapy with regard to implant survival.
 An implant-supported prosthesis is not a guarantee for uncompromised oral
function after head and neck oncology treatment, but can be considered
a significant factor contributing to the well-being of these patients

65.  The objective of this systematic review was to investigate the effectiveness of HBO
therapy on dental implant survival rate in irradiated maxillofacial patients who require
prosthodontic rehabilitation.
 An electronic search without time restrictions was undertaken in April 2016 using
databases: PubMed, Google Scholar, and the Cochrane Oral Health Group Trials
Register

68.  The results show decreased
implant failure rate in HBO group
(9.21%) compared to non-HBO
group (22.44%).
 The potential limitations of this
study are amount of radiation
doses used, period lasting from
radiotherapy to the placement of
the implants, and follow-up
period which varies for every
subject of the included study,
which can affect the treatment
outcome.

69.  Although there are many sensitive articles
published about HBO, including a number of
review papers, RCTs are still lacking.
 According to the statistical analysis, it can be
concluded that preventive HBO therapy can
reduce the risk of implant failures in
irradiated patients by 1.21 (relative risk) with
95% confidence interval (P < 0.001).
 HBO can be the effective treatment
protocol for the implant treatment in
irradiated maxillofacial patients.

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