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The Predictive Value of Patient-Based
Questionnaires in Treatment of Edentulism
Sittana Elfadil Hassan Ahmed
DDS (A U ST), MFD RCSI
DECLARATION
• I declare that this thesis has not been subm itted as an exercise for a degree at this or
any other university and it is entirely m y own work.
• I acknow ledge assistance from Ms. Bridget Johnston in relation to statistical analysis
and the collaboration w ith Cork U niversity Hospital in data collection in Cork's
centre.
• I agree to deposit this thesis in the U niversity’s open access institutional repository or
allow the library to do so on my behalf, subject to Irish Copyright Legislation and
Trinity College Library conditions o f use and acknow ledgem ent.
iJ^T R IN IT Y C O L L E G E '
5 JAN 2015
«^^ L I E R A ^ 'D U B L I N
Signed:
SUMMARY
Statement of the problem:
Edentulism is a common chronic disabling condition that
impacts on an individual’s health, self-perception and social interaction. Although edentulous
people present with a wide range o f functional and psychological needs, which may require
different levels o f intervention, there is no systematic approach to their diagnosis and
treatment.
Aim:
Identify patient groups with characteristics o f edentulism that relate to choice of
treatment, satisfaction and success o f conventional complete dentures (CCDs) and implant
overdentures (lODs).
Materials and methods:
Edentulous patients attending Dublin and Cork Dental Hospitals
were provided with CCDs and then offered the option o f two small-diameter dental implants
in the mandible. They were assessed at three time points: T l, baseline, T2, three months after
the provision CCDs, and T3, three months after the provision o f mandibular lODs. The
interview consisted o f a clinical examination (objective measures) using the Prosthodontic
Diagnostic Index for Complete Edentulism (PDI-CE) and a set o f questionnaires (subjective
measures) including Oral Health Impact Profile - Edentulous (OHIP-EDENT), Denture
Satisfaction Questionnaire (DSQ), Life Orientation Test (LOT) - an optimism scale, and a
Dental Treatment Uptake scale (DTUS). Patients were divided into subgroups based on T2
general satisfaction and their implant treatment preferences.
comparable for those who chose and did not choose implant treatment and also for those who
were satisfied and dissatisfied after T2. The LOT scores were similar among subgroups with
p-values o f 0.19 for implant choice subgroups and 0.43 for T2 satisfaction groups. Those who
chose implants reported significantly
{p =
0.01) higher DTUS levels at baseline compared to
those who refrained this choice (14.6 vs. 46.2). T2 satisfied patients had significantly
{p =
0.04) higher DTUS scores at baseline than T2 dissatisfied patients (44.7 vs. 41.5). Those who
chose implant treatment were significantly younger
(p < 0.05), had newer dentures at
presentation
{p < 0.05), and reported low baseline OHIP-EDENT total scores {p = 0.02). The
majority o f participants were satisfied with CCDs (67%) compared to dissatisfied patients
(22%), yet only 28% o f the latter group accepted implant treatment. Fifty percent o f patients
reported fear o f surgery as their main barrier.
ACKNOWLEDGEMENTS
I w ould like to thank Cork University Hospital for their collaboration, the gatekeepers for
their help and professionalism . Dr loannis Polyzois and D r Paul Brady for executing the
surgical part o f the study, H ealth Research Board and ACE Surgical Supply Com pany Inc©
for sponsorship, and lastly the participants o f this study for their w illing participation, w ithout
all this study w ould not have been possible.
I w ould like to express my gratitude to my supervisor P ro f Brian O'Connell for the
invaluable advice and guidance through the learning process o f this thesis.
1 w ould like to express my appreciation to Ms. Bridget Johnston for her priceless assistance
in statistics and also P ro f Charles N orm and for statistical expertise. My special thanks to
P ro f Finbarr Allen for his guidance and advisory role.
TABLE OF CONTENTS
Title page...I
D eclaration...II
S u m m ary ... I ll
A cknow ledgem ents...V
T able of C o n te n ts... VI
T able o f Figures... XI
Table o f T a b le s... X III
1
C h a p te r O ne: In tro d u c tio n ... 1
1.1
Edentulism...1
1.1.1
International demographics o f edentulism...2
1.1.2
National demographics o f edentulism ... 4
1.1.3
Aetiology and risk factors for edentulism...5
1.1.4
Classification o f edentulism...6
1.1.5
Impact o f edentulism on oral and general health...6
1.1.6
Treatment options for edentulism ...7
1.1.6.1
Conventional complete d en tu res... 8
1.1.6.2
Implant-retained and tissue-supported prostheses...9
1.2.2
A ttachm ent system for im plant o verden tu res...11
1.2.3
Size o f im plants for overd en tu res... 12
1.2.3.1
Small-diameter im plants for overd en tu res... 12
1.2.4
Success o f im plant overdentures... 14
1.3
Treatment o u tco m es... 14
1.3.1
Quality o f L ife...16
1.3.1.1
Quality o f Life in oral h e a lth ... 18
1.3.1.2
M easuring oral-health related quality o f L ife... 19
1.3.1.3
Oral Health Impact Profile questionnaire...21
1.3.1.4
A modified short version of OHIP for edentulous a d u lts...24
1.3.2
Patient satisfaction... 24
1.3.2.1
M easuring satisfaction with d en tu re s...25
1.3.2.2
Denture satisfaction questionnaire... 26
1.3.3
OHRQoL and Denture satisfaction outcom es in edentulism and its treatment .27
1.3.4
Dental treatment uptake by edentulous p a tie n ts... 29
1.3.4.1
Dental Treatment Uptake S cale... 30
1.3.5
Psychological param eters... 31
1.3.5.1
Life Orientation T e s t ... 32
2
Aims and objectives... 33
2.1
Rational for current study...33
2.3
A im ...36
2.4
O bjectives... 36
2.5
H ow will this research contribute to the fie ld ? ...37
3
Chapter Two: Material and methods... 39
3.1
Patient recru itm e n t...39
3.2
Ethical approval... 41
3.3
Data collection and sto ra g e ...41
3.4
Operation o f the stu d y ...42
3.5
Study booklet... 45
3.5.1
Demographic data and relevant histories...46
3.5.2
Clinical assessm en t...47
3.5.2.1
American college o f prosthodontists' Prosthodontic Diagnostic Index for
Complete Edentulism (P D I-C E )... 47
3.5.3
Q uestionnaires... 52
3.5.3.1
Oral health Im pact P ro file ... 52
3.5.3.2
Satisfaction w ith dentures... 54
3.5.3.3
Dental treatm ent uptake scale... 56
3.5.3.4
Life Orientation T e s t ... 58
3.6
Implant s u rg e ry ... 60
4
Statistical an alysis...
5
Funding, sponsorship and institutional affiliation
63
66
6
Chapter Three: R esults... 68
6.1
Descriptive statistics... 68
6.2
Investigation o f edentulous patients' degree o f satisfaction and Oral H ealth Impact
Profile at T 1 ,T 2 , and T 3 ... 72
6.3
Exam ination o f the PDI-CE diagnostic com plexity o f p a tie n ts... 78
6.4
Investigation o f the psychological trait o f optim ism o f the participants using the Life
O rientation T e s t... 81
6.5
Exam ination o f "Dental Treatm ent U ptake Scale" scores in edentulous subgroups 83
6.6
Comparison o f groups based on im plant choice, exam ining characteristics that may
indicate treatm ent c h o ic e ... 83
6.7
Investigation o f groups based on satisfaction and exam ination o f baseline
characteristics o f edentulous patients that can indicate satisfaction and treatm ent success 89
7
Chapter Four: D iscussion... 96
7.1
General aspects... 96
7.2
Basic data descriptive an aly sis...99
7.3
Investigation o f edentulous patients' degree o f satisfaction and Oral H ealth Impact
Profile for Edentulous at T l, T2, and T 3 ... 101
7.5
Investigation o f the psychological trait o f optim ism o f the participants using the Life
O rientation T e s t... 106
7.6
Exam ination o f "Dental Treatm ent Uptake Scale" scores in the edentulous
subg ro ups...107
7.7
Com parison o f groups based on im plant choice, exam ining characteristics that may
indicate treatm ent c h o ic e ... 108
7.8
Investigation o f groups based on satisfaction and baseline characteristics o f
edentulous patients that can indicate satisfaction and success for treatm ent... 113
7.9
O utcom es o f sm all-diam eter im plants... 116
8
Limitations, future studies and su g g estio n s... 117
9
Chapter Five: C o n c lu sio n s...121
10 C happter Six: A ppendices and R e fere n ce s...124
10 A p p e n d ic e s... 124
TABLE OF FIGURES
Figure 1-1: C om pletely edentulous m o u th ... 1
Figure 1-2: C onventional com plete dentu res...8
Figure 1-3: Im plant o v erd en tu re... 9
Figure 1-4: Sm all- and regular- diam eter im plants... 13
Figure 1-5: Conceptual model showing pathw ays for the edentulism -general health
relationship ( 7 6 ) ... 18
Figure 1-6: C riteria for evaluating health-related quality o f life m e a su re s ... 21
Figure 1-7: Conceptual model for m easuring oral health - Locker, 1988 ... 22
Figure 3-1: Study tim e/event li n e ... 43
Figure 3-2: Basic D a ta ... 46
Figure 3-4: Panoram ic X-ray o f Class I p a tie n t... 49
Figure 3-3: Clinical photo o f class I patient... 49
Figure 3-5: Exam ple o f class II maxilla and m an d ib le...50
Figure 3-6: Clinical exam ples o f a class III p a tie n t...51
Figure 3-7: Clinical presentation o f a Class I V ... 52
Figure 3-8: Life O rientation T e s t...59
Figure 3-9: X -R ays custom -m ade aiming d e v ic e ... 63
Figure 6-1: Flow chart o f p articip an ts...69
Figure 6-4: Y ears o f edentulism at T 1 ...70
[image:13.543.6.528.26.727.2]
(14)TABLE OF TABLES
Table 1-1: Prevalence (percentage) o f edentulousness in the elderly reported for selected
cou ntries...3
Table 1-2: Percentage o f adults in Ireland who were edentulous by age group, gender and
m edical card status in 1989/’90 and in 2000/’02 ... 4
Table 1-3: N um ber o f adults, and the percentage who were edentulous, by age group and
general health status (ASA) (17 )... 5
Table 1-4: Oral health outcom e measures - A dapted from Locker D and Allen F, 2007 (83) 20
Table 3-2 Prosthodontic D iagnostic Index for Complete Edentulism (P D I-C E )...48
Table 3-3 O H IP -E D E N T ...53
Table 3-4 Denture Satisfaction Q uestionnaire...55
Table 3-5: Dental Treatm ent Uptake S cale...57
Table 6-1: D em ographic and denture history data descriptive statistics at baseline ( T l )
68
Table 6-2: Patient g e n d e r...68
I'able 6-3: Patient O ccu p atio n ... 71
Table 6-5: D escriptive data for O H IP-D EN T total and dom ain scores for each tim e po in t....75
Table 6-6: W ilcoxon signed-rank test p-values for DSQ scale... 76
Table 6-7: W ilcoxon signed-rank test p-values for O HIP-EDENT scale...77
Table 6-8: Intraclass Correlation Coefficient for inter-rater reliability and reproducibility o f
PD I-C E ...79
Table 6-9: PDI-CE Classification in implant choice subgroups...80
Table 6-10: PDI-CE Classification according to satisfaction g ro u p s...81
c h a p te r One
1 Introduction
To raise new questions, new possibilities, to regard old problem s fro m a
new angle, require creative imagination and marks real advance in science
- Albert Einstein
1.1 Edentulism
Edentulism is
"the state o f being edentulous; without natural teeth"
(1). A ccording to the
World Health O rganization (W HO) (2), it meets the International Classification o f
Functioning D isability and Health's definition o f impairment, disability, handicap and
dysfunction since an im portant body part w hich is associated with social and medical
disability is lost. Total tooth loss is an incapacitating perm anent condition and is described as
the “ultim ate m arker o f disease burden for oral health” (3).
Edentulism can affect a person's quality o f life (QoL) and daily activities in m any aspects:
socially, functionally, and psychologically (2, 4-7). Being edentate is a very basic indicator o f
oral health; hence many oral health organizations are targeted tow ards natural teeth
preservation program s (8, 9). Edentulism continues to be a personal problem , a professional
responsibility, and a continuous public health concern (9).
1.1.1 International demographics of edentulism
Edentulism is an international phenom enon. In 2010, around 158 m illion people globally
w ere estim ated to be edentate (2.3% o f the population), and w om en are m ore com m only
affected (2.7% ) than m en (1.9% ) (10). Oral disease com bined (edentulism , caries, and
periodontitis) brought about 15 m illion "years lived with disability" (YLD s), a term used to
describe life lived in less than ideal health. Those three conditions have equal shares in YLDs
(
10).
The pace o f tooth loss has declined rapidly in most developed countries in the past two
decades. On the other hand, given that people now live longer, the prevalence o f edentulism
WMO region/Country Percentage edentulous
Age group (years) African
Madagascar 25 65-74
The Americas
Canada 58 65*
USA 26 65-69
Eastern Meditenanean
Egypt 7 65+
Lebanon 35 65-75
Saudi Arabta 3 1 ^ 654.
European
Albania 69 65*
Austria 15 65-74
Bosnia and HefTegovina 78 65*
Bulgaria 53 65*
Denmark 27 65-74
Finland 41 65*
Hungary 27 65-74
Iceland 72 65*
Italy 13 65-74
Lthuania 14 65-74
Poland 25 65-74
Romania 26 65-74
Slovakia 44 65-74
Sk}venia 16 65*
United Kingdom 46 65*
South-East Asia
India 19 65-74
Indonesia 24 65*
Sri Lanka 37 65-74
Thailand 16 65*
Western Pteific
Cambodia 13 65-74
China n 65-74
Malaysia 57 65*
Singapore 21 65*
I 'a h l e l - l : l’ r e \ a l c n c e ( p e r c e n t a g e ) o f e d e n t i i l o u s n e s s in t h e e l d e r l y r e p o r t e d f o r s e l e c t e d c o u n t r i e s
1.1.2 National dem ograp h ics o f ed en tu lism
Edentulism in Ireland has sim ilarities to global trends. D espite the decrease in the percentage
o f the edentulous population since 1979 (17), it has not and will not disappear soon (16).
A ccording to census, the population o f the elderly in Ireland is rising and 11% is aged 65 or
over (18).
Although considered a developed country, Ireland possesses one o f the highest percentages o f
edentulous people (19). A ccording to the national survey o f Oral Health o f Adults undertaken
between O ctober 2000 and June 2002, 40.9% o f those aged 65 years or over w ere edentulous
(17), that is; around 180,000 people (18). Am ong edentulous people who were 65 years or
older, 6% had no dentures in 2000/02. Around 47% o f edentulous adults were w earing
com plete dentures that are at least 10 years old. A high percentage (40.8% ) o f those 65 years
or over was not satisfied with their dentures. Edentulism am ong the same age group was
more prevalent in fem ales (45.6% ) than m ales (34.6% ) and in m edical card holders (45.6% )
than non-holders (29.4% ) - Table 1-2 (17).
M a l e
l 9 8 9 / ’90
I
2 0 0 0 / ’02M e d i c a l C a r d H o l d e r s
F e m a l e
l 9 8 9 / ’9 0 \ 2 0 0 0 / ’02
T o t a l
l 9 8 9 / ’90
I
I OOQI ' 021 6-2 4 y e a r - o l d s 0 0 0 0 0.0 GO 0 0 0 0 '
3 S -4 4 y e a r - o l d s 3 2 12 7 8 1 5 6 J 1 4
6 5 + y e a r - o l d s 48.2 40.1 72.2 4 9 2 6 2 2 4 5 6
N o n M e d i c a l C a r d H o l d e r s
M a l e Fenrl a l e T o ta l
l 9 8 9 / ’90 2 0 0 0 / ’02 1 9 8 9 / ’9 0 2 0 0 0 / ’02 19 8 9 /’90 2 0 0 0 / ’02
1 6-2 4 y e a r - o l d s 0.0 0 0 0.0 0 0 0.0 0.0
3 5 - 4 4 y e a r - o l d s 2.7 0 1 3 4 0.7 3 4 0.4
6 5 + y « a r - o l d s 1 7 0 23 9 42 9 35.2 3 0 8 2 9 4
[image:21.543.5.528.23.796.2]Edentulism also is m ore evident in those w ith systemic diseases (classified according to the
A m erican Society o f A naesthesiologists -A SA - Classification) w ith percentages o f 35.1% ,
53.8% and 47.7% o f ASA 1, ASA 2 and A SA 3 o f adults respectively - Table 1-3 (17).
A g e A S A 1 A S A 2 1 A S A 3 A S A 4 Total
G r ou p n % Edent n % E d en t n 1% Edent n % Edent n % Edent
16-24 1139 0 0 50 0 0 5 ♦ 0 * 1 194 0 0
3 5-44 914 0 8 57 2 9 5 * 0 « 976 0 9
65+ 464 3S 1 206 53 8 43 4 7 7 1 * 714 40 9
* n < 30 I a b l e 1-3: \ i i m l ) e r o f acliilts. a n d t h e p e r c e n t a g e « l i o w e r e e d e n t u l o u s , b \ a g e g r o u j i a n d g e n e r a l h e a l t h s t a t u s
( AS A) (17)
1.1.3 Aetiology and risk factors for ed en tu iism
Tooth loss is the term inal consequence o f m ultiple etiological factors. A lthough total
edentulism is usually acquired due to biologic processes (caries, periodontitis, pulpal disease,
traum a, or cancer), it can be congenital. Caries and periodontal disease are the main two
etiologic factors associated with edentulism (12). N on-biologic causes related to dental
treatm ent include access to care, patient preference, third-party paym ent, and treatm ent
options (12). O ther causes include iatrogenic, traum atic and therapeutic reasons (9).
T ooth loss is strongly associated with age although it is not necessarily a consequence o f
ageing (13).
Also, edentulousness is inversely related to income level and education.
Personal and behavioural aspects such as patient neglect and poor oral hygiene are strong
influencing risk factors. Other prognosticators include gender, socio-econom ic class, marital
1.1.4 Classification o f ed en tu lism
Edentate people exhibit a wide range o f physical and biological differences and cannot be
grouped as one diagnostic group. The A m erican College o f Prosthodontists (ACP) has
established the Prosthodontic D iagnostic Index for Com plete Edentulism (PDI-CE) to
classify com plete edentulism according to the severity o f diagnostic findings. This
classification system can assist the dental profession to standardize the diagnostic criteria and
plan suitable treatm ent for this group o f patients. Four classes are identified, with Class I
having the sim plest clinical presentation and Class IV being the m ost com prom ised. The ACP
has identified objective criteria to classify patients for each category (20).
PD I-CE is the first m ultidim ensional diagnostic tool for edentulousness. The Harvard study
(21) has identified its construct validity by dem onstrating a high percentage o f correct global
diagnosis. Pan et al.(22) dem onstrated good intra- and inter-exam iner reliability o f PDI-CE
but did not find a relationship between categories o f severity and patient-perceived denture
satisfaction.
1.1.5 Impact o f e d en tu lism on oral and general health
Edentulism is a chronic condition that can affect basic life actions such as eating, speaking,
and m eeting people, w hich can affect negatively the social and psychological w ell-being o f
those w ho cannot cope (6).
Tallgren (23), in her classical longitudinal study o f residual alveolar ridges reduction in
height o f the residual alveolar bone and the dim ensions o f the denture bearing area
significantly dim inish over time. Substantial loss can lead to soft-tissue profile changes.
Furtherm ore, edentulous people can suffer from functional and sensory disorders o f oral
organs such as m ucosa, m uscles and salivary glands (13).
Tooth loss is a disability that impairs m astication. Bite strength and m asticatory force with
com plete dentures falls to about one-fifth to one-fourth that o f a dentate dentition (24).
Denture w earers may modify their food choices and have less than an optim um diet with a
low er intake o f protein, fibre, calcium , iron, and vitam in C than those with a natural dentition
( 8 ).
Edentate people are in greater risks for various systemic conditions and m ortality rate.
Edentulism has deleterious consequences on general health as it increases the risk o f
cardiovascular and gastrointestinal diseases, type II diabetes m ellitus, chronic renal diseases,
and sleep-disordered breathing (13).
1.1.6 Treatment options for edentulism
Edentulous individuals with different clinical presentations, physical and psychological needs
and co-m orbidities create diagnostic and treatm ent planning difficulties that dem and various
levels o f prosthetic treatm ent. The m anagem ent o f edentulism requires understanding o f the
tissue-supported rem ovable overdentures, im plant-supported and retained fixed com plete
dentures.
1.1.6.1 Conventional complete dentures
For over a century, provision o f conventional com plete dentures was the accepted therapy for
an edentulous patient. Dentures restore appearance and function to some extent. D espite the
advances in denture m aterials, conventional dentures, particularly the m andibular, have a
reputation for discom fort as well as poor stability and retention (9, 14, 25). O ver 50% o f
m andibular com plete denture wearers suffer from com prom ised retention and stability, and
66% o f elderly patients were not happy with their com plete dentures (26, 27). Such
dow'nsides may im pair a person psychosocially and physically (14). D espite all the
inadequacies o f com plete dentures, many people are satisfied, adapt well to their disability
and manage to eat, talk and function with these prostheses (6, 28-30). For those who struggle
to adapt, alternatives m ust be considered (31).
[image:25.543.13.526.25.792.2]Denture w earing com pared to natural teeth may be associated w ith less self-confidence,
prem ature ageing, distorted self-im age, and changes in social activities and interrelationships
(5). Com pared to no teeth dentures im prove appearance and socializing, w hich may im prove
self-im age and psychological w ell-being (13). For certain people w here age, oral and general
health and socio-econom ic status conditions allow, com plete dentures can be a safe,
predictable, and econom ic treatm ent option (29).
The construction technique and denture quality do not relate directly to denture success
unless there is an obvious technical fault (denture base extension, ja w relation) that may
identify the reason for dissatisfaction (25). On the other hand, the literature strongly points
tow ards patient-related factors as key factors to success (6, 9).
1.1.6.2 Implant-retained and tissue-supported prostheses
The introduction o f dental im plants, and consequently im plant overdentures, overcam e many
draw backs o f conventional denture treatm ent. By im proving stability and retention, im plants
addressed several functionality problem s so that an im plant-retained overdentures was
considered by the M cG ill (14) and York [4] consensuses as the
"m inim um offered first-choice standard o f care for the
edentulous m andibular arch". D espite these consensuses and
the w idely available high-level supporting evidence, the
provision o f im plant overdentures is not a routine treatm ent
(14). Cost and provider expertise are the probable barriers
Burns concluded in his review (26) that the following general consensus about m andibular
dentures is substantiated in the literature:
• Com prom ised retention and stability negatively im pact the treatm ent outcom es o f
conventional dentures
• Implants dem onstrate rem arkable success rates in the anterior m andibular region and
they also slow the bone resorption rate
• Implant m andibular overdentures have many benefits over conventional dentures
rendering the form er a superior treatm ent choice from a patient satisfaction point o f
view
• Peri-im plant tissue and bone react favourably in overdenture treatm ent
• There is a potential for com plications that necessitates a structured m aintenance
scheme with im plant overdenture treatm ent
Implant overdentures offer m any advantages over im plant-supported fixed prosthesis;
they are less expensive and provide better accessibility for oral hygiene and less food
impaction, with no significant difference regarding function and patient satisfaction (9,
32, 33). Some long-term denture wearers have expressed a preference for overdentures
over fixed-im plant prostheses (32).
1.2 Implants for overdentures
random ised controlled trials and system atic reviews, supports the superiority o f m andibular
im plant-overdentures over their conventional counterpart from a general satisfaction and oral-
health quality o f life viewpoint, regardless o f the im plant anchor system (14, 15, 35). This is
probably due to an im provem ent in denture stability, retention, com fort, chew ing ability and
nutrition (15, 36). A systematic review (37) validated that the m asticatory ability o f
m andibular im plant overdentures is significantly im proved over conventional dentures, but
only w here ridges are severely resorbed and/or m al-adaptation to conventional treatm ent is
evident.
1.2.1 Number of implants for overdenture treatment
V arious num bers o f im plants ranging from one to four have been advocated for m andibular
im plant overdentures. M cGill (15) and York (14) consensus statem ents recom m ended two
implants. Four versus two im plants have been shown not to be significantly different
regarding im plant survival, com plications and patient satisfaction. Hence, a tw o-im plant
overdenture is advantageous given its cost-effectiveness, prosthetic sim plicity and surgically
m inimal invasive nature (33, 38). Reducing the num ber further to one im plant has also been
advocated (39). A lthough prom ising, single im plant overdentures may pose com plications
related to anatom ical factors and residual ridge resorption. Further evidence is still required
(38).
1.2.2 Attachment system for implant overdentures
clip attachm ents on rigid bar joining im plants, and (3) m agnet attachm ents. It is concluded
that overdentures may m aintain health and excellent prognosis irrespective o f retention
systems used over ten years o f service (40). One review (41) has stated that there is no
significant difference in stress distribution betw een free-standing and splinted attachm ents
provided that the overdenture is w ell-designed and treatm ent conditions are controlled. A
high level o f evidence cannot suggest significant superiority o f one attachm ent system over
the other but there is reasonable evidence to suggest inferior satisfaction w ith m agnets (42).
Bar and clip attachm ents tend to show a need for less aftercare (43). It is uncertain w hich
attachm ent is best biom echanically. M ericske-Stem (44) advocates selection based on a
particular clinical scenario and specific patient's needs.
A lthough un-splinted two im plant-overdentures provide low er retention values than splinted
implants, this difference is not reflected in patients' satisfaction ratings. Furtherm ore, two-
im plant retained overdentures exhibited no difference regarding im plant failure, marginal
bone levels, probing attachm ents w hether the im plants were splinted or not (45). Therefore,
the sim plest treatm ent form (single stud attachm ents) is sufficient (46).
1.2.3 Size of implants for overdentures
1.2.3.1 Small-diameter implants fo r overdentures
include potential cost reduction with m ini-im plants, m inim ization o f discom fort and surgical
traum a and the possibility o f im m ediate loading in patients who could not have been treated
w ith im plants otherw ise (48, 49).
Slightly m ore bone loss was observed by Jofre et al. (50) around two
sm all-diam eter im plants in com parison to standard-diam eter implants.
This was attributed to increased m om ent loads due to higher the flexural
m odulus in smal 1-diameter im plants and subsequently increased peri-
im plant bone resorption. On the other hand in a review by Renouard (51),
bone loss around reduced-diam eter im plants was found to be com parable
to that around standard-diam eter implants. Treatm ent with m ini-im plants
l i s m c i - 4 : S m n i i - i uui r e j i ul i i r - d h i m e t e r i m p l a n t smay be less predictable in the m axilla and with short implants(52).
Though the cost o f im plant treatm ent can be an issue for edentulous patients, another obstacle
is anxiety about surgery (53). Interestingly, in one study even w hen im plants were offered for
free, 36% o f edentulous patients refused treatm ent m ainly due to apprehension about surgical
risks (54). Sm all-diam eter im plants may offer a m ore appealing treatm ent option w ith sim ilar
success, especially if a flapless protocol is used (53). Certainly, the possibility o f im m ediate
restoration o f m astication and aesthetics for patients during the healing period is an advantage
o f sm all-diam eter im plants (55, 56).
restored w ith conventional protocols. The long term success o f m ini-im plants placed w ith a
flapless protocol, unsplinted and im m ediately loaded, remains to be dem onstrated.
1.2.4 Success of implant overdentures
It has been reported that dentures retained by narrow -diam eter im plants provide good patient
satisfaction; and clinical success and survival rates for these im plants are acceptable (55, 59,
60). A recent literature review (53) has exam ined the survival o f 10,093 sm all-diam eter
im plants in 22 studies with follow up duration ranging from 5 m onths to over 9 years.
Survival rates w ere com parable to those o f standard w idth im plants w hich ranged from 95%
to 99.9% (53).
1.3 T reatm en t ou tcom es
D ecision m aking in dentistry involves an appreciation o f the outcom e o f treatm ent m easures
that com pare the benefits o f one treatm ent option over another. G uckes et al. (61) have
identified four categories o f treatm ent outcom es for im plant treatment:
•
Survival/longevity (im plant and prosthesis survival, m ortality and morbidity)
•
Physiological/Physical (m asticatory efficiency, bite force, bone level, nutrition
impact)
•
B ehavioural/psychological (appearance, body image, quality o f life, treatm ent
satisfaction, self-esteem)
The literature describes many outcom e m easures designed to evaluate chewing, denture
satisfaction, personality, self-confidence, body image and psycho-social well-being. Those
scales are either standardized; o f know n validity and reliability, or ad hoc; developed by
investigators for the purpose o f the research (62). The choice o f w hich clinical outcom e is
used depends on the question asked and who is asking. Each researcher has a different
hypothesis to test and each party in the treatm ent process (patient, clinician, treatm ent payer)
has different concerns. Thus, no one universal outcom e scale exists to m easure treatm ent
outcom es in prosthodontics (63).
im plant prostheses have highlighted that denture satisfaction and oral-health quality o f life
are the m ost im portant patient-centred outcom e measures in the m anagem ent o f edentulism .
1.3.1 Quality o f Life
Quality o f Life (QoL) is a term that was initially identified in 1920 but not used extensively
and in its today's context until 1960s (70). Since then, many definitions have evolved. QoL is
a phrase used to em brace several notions including health status, function, and life
circum stances (13). QoL is defined by the W HO as
"an individua l’s perception o f his or her
position in life, in the context o f the culture an d value system s in which they live, an d in
relation to their goals, expectations, a n d concerns. It is a broad ranging concept affected in a
com plex way by the p e r s o n ’s p h ysica l health, psychological state, level o f independence,
social relationships, and their relationships to salient fe a tu res o f their environm ent" (71). It
is im portant to find out how satisfied or not a person is about a particular aspect o f his/her
life, keeping in mind that this can be highly individual (64). QoL differs between and w ithin
people. It changes over tim e for the same individual due to variation in experiences or any o f
its constituting elem ents (13, 72). For exam ple, changes in psychological patterns such as
adaptation, self-control, and expectancy can m odify and change attitude tow ards the same
event over tim e (72). QoL is a m ultidim ensional term that considers variable aspects o f life
(73) and relates to how personal hopes m ay m atch with an individual's experience (74).
is derived from issues o f psychosocial w ell-being, com fort, function, confidence, aesthetics,
and patients' perception on treatment, quality o f life is a fundam ental asset in planning
treatm ent (62).
W HO have defined health as
"a state o f complete physical, m ental and social w ell-being and
not m erely the absence o f disease or infirm ity”
(75). H ealth-related quality o f life (HRQoL)
has em erged from understanding this m ulti-dim ensional definition which incorporates the
physical and psycho-social elements o f w ell-being. HRQoL is defined as the
"optimum levels
o f mental, physical, role (e.g. work, parent, carer, etc.) a n d social functioning, including
General resistance resources
Sociodemographic vanables
Health care
policy
nutrition
Steep disease
(^lalityof life
General Health
Physiologic modifications
Psychological
inqjacts
Cheumg efficiency
Bite force
Masticatoiy ability
Health coodition and health behauour
F i g u r e 1-5: C o n c e p t u a l m o d el s h o w in g p a t h w a y s f o r t h e e d e n t u l i s m - g e n e r a l h e a l t h r e la t i o n s h i p (76)
1.3.1.1 Quality o f Life in o ra l health
[image:35.543.14.533.21.787.2]Oral health-related quality o f life (O HRQ oL) was first described by G ift et al. in 1992 (78) as
"the self-perceived inform ation particularly related to oral health. This include the fu n ctio n a l
(e.g. eating, speaking), social (e.g. m eeting other people), an d psychological (e.g. self-image,
s e lfe ste e m ) impacts o f oral disease to general well-being". Since the recognition o f
O HRQ oL as a valid factor in patient evaluation in alm ost every aspect o f physical and
psychosocial oral healthcare, m any instrum ents have been developed (79). OHRQoL can be
used to assess both negative and positive perceived oral health outcom es (79).
O HRQ oL is im portant since: (1) oral health can affect general health; (2) patient-centred
inform ation is becom ing more evolved in the decision-m aking practice, (3) the necessity for
evidence-based practice is widely known, (4) traditional scales failed in m anagem ent o f many
conditions (80). M ore and more, appreciation o f the im portance o f patients’ perceptions o f
oral health is expanding in the estim ation o f general w ell-being and healthcare outcom es (13).
1.3.1.2 M easuring Oral-Health R ela ted Quality o f Life
specific treatment in the oral cavity or to an oral clinical condition (76). This is because
generic measures may be affected by relevant external conditions if used in specific cases and
consequently may miss responsiveness. Rather, a specialized measure can be developed to be
more appropriate, provided it suits the population, shows adequate responsiveness to changes
resuhing from treatment, demonstrate evidence o f reliability (gives same result if re-tested in
the same sample), content validity (covers all relevant aspects o f the outcomes o f interest),
and construct validity (related to other scales in the expected way) (63).
Since 1997, many OHRQoL instruments have been published, examples are shown in Table
1-4(83).
P re-1 9 9 7 • Social Im p acts o f D en tal D isea se (C u s h in g A M et al,, 1986)
• G e n e r a l (G e r ia tr ic ) O ra l H ea lth A sse ssm e n t In d ex (G O IlA I )(A tc h iso n , 1990) * • D ental Im pact P ro file (D IP ) (S tra u s R P. 1993)
• O ra l H ealth Im p a ct P r o file (C H I P ) (S la d e D G , 1 994) *
• O ra l Im p a cts on D a ily P e r fo r m a n c e s (O II)P ) (A d u ly a n o n S , 1997) * • S u b je c tiv e O ral H ealth S tatu s In d ic a to rs (S O H S l) (L o c k e r D ,1 9 9 4 ) • O ral H e alth -R ela te d Q u a lity o f Life M ea su re (K re ssin N R 1 9 9 7 ) • D en tal Im p act on D aily L iv in g (D ID L S ) (L ea o A . 1994) • O ral H ealth Q u a lity o f L ife In v e n to ry (C o rn ell JE , 1997) • R an d D en tal Q u e stio n s (D o lan T A . 1997)
P o s t- 1997 • O H Q o L -U K (M c G rath C, 2 0 0 1 )
• C h ild O ra l H ea lth Q u a lity o f L ife Q u e stio n n a ir e (C O H Q o L ) (J o k o v ic A , 2 0 0 2 )* • C h ild O ID P (G h e ru n p o n g S, 2 0 0 4 )
• O H R Q O L for D en tal H y g ien e (G a d b d u ry -A m y o t C C , 1999) • O rth o g n a th ic Q O L Q u e stio n n a ire (C u n n in g h a m S J, 2 0 0 0 )
• S u rg ical O rth o d o n tic O u tc o m e Q u e stio n n a ire (S O O Q ) (L o ck e r D, 2 0 0 7 )
l a h l e 1 -4 : O r a l h e a lt h o u t c o m e m e a s u r e s - A d a p t e d f r o m l . o c k e r I) a n d A lle n K. 2 0 0 7 ( 8 3 ) (M arked with * are the m ost commonly used)
Some o f these scales are ambiguous regarding their construct validity (what actually these
tools are supposed to measure) as well as their importance in the target-population.
Furthermore, some scales are claimed to be patient-centred while they are in fact expert-
centred (83). Locker and Allen (83) have proposed guidelines to assess outcome measures o f
D id th e invesligatt>rs eunceptiuilly id en tify w h a t th e y m eant by q u a lity o f life?
D id Lhciy sla te th e d o m a in s they w an te d to m e asu re as co m p o n en ts o f q u a lity of life?
17id the in v estig ato rs giv e reasons for choosing Ihe in stru m e n ts they used?
Did th e investig.'itors -iggregate the resu lts from m u ltip le item s, d o m a in s o r in stru m o n ts into a single com posite score?
W ere p atien ts ask ed to give th eir ow n global ratin g for q uality of life?
W as overall q u ah ty of life d istin g u ish ed from health-related quality o f life?
W ere p atients invited to su p p le m e n t the item s listed in the in stru m e n ts offered by th e investigators? If so, w ere these supplen'iental item s incorporated
in to the final ratii\g?
W ere p atien ts aslted to indicate w hich item s w ere personally im p o rta n t to them?
If so, w ere these im portance ratings in c o rp o rated in to the final rating?
Do th e au th o rs shoiv that aspects of p atien ts' lives they have m easu red are im p o rta n t to the patients? If not, have p revious stu d ies d em o n strate d their
im portance?
Do the Investigators exam ine aspects of p a tie n ts' lives th a t clinical experience indicates p atients value? Arc there aspects of IIR QL that are im p o rta n t to
patients that have been om itted?
W ere indiv id u al p atien ts asked to directly placc a value on th eir lives?
F i g u r e 1- 6: C r i t c r i n f o r e \ : i h i a t i n g h e a l t h - r e l a t e d q u a l i t y o f l i f e m e a s u r e s
In a research context, OHRQoL measures can be used as a survey tool to look at trends in
oral health and population-based needs. Oral healthcare planners can gain much from
indentifying individual characteristics and needs when planning for population-based policy
m odels. In clinical studies, OHRQoL can be used as an evaluative outcom e measure. For
exam ple, in longitudinal trials; pre- and post- intervention assessm ent can indicate service
users' perceptions o f treatment effectiven ess and efficien cy, and can be used to evaluate
quality and improved care (79).
1.3.1.3 Oral Health Im p a ct Profile q u estio n n a ire
The Oral Health Impact Profile (OHIP) is a
'‘sc a le d index o f the so c ia l im pact o f oral
w idely used questionnaire and considered the m ost com prehensive and sophisticated outcom e
scale o f OHRQoL (85). OHIP w as developed by Slade and Spencer in 1994 (84) to m easure
the impact o f oral health on the quality o f life. It evaluates the self-perception o f the "social
impact" o f oral conditions on som eone's life and w ell-being, taking into account the
dysfunction, discom fort and disability caused by the oral disorder (84).
OHIP has seven dim ensions, namely; functional lim itation, physical pain, psychological
discom fort, physical disability, psychological disability, social disability, and handicap (84).
These domains have em erged from the theoretical conceptual fram ework model o f oral health
by Locker (86) (Figure 1-7) w hich in turn is based on the W HO classification o f im pairm ent,
disability and handicap (2). This model represents a m ajor shift in the dental care tow ards
patient-oriented care (87). Com plete edentulism fits Locker's model and W HO's classification
since it is considered an im pairm ent (a part o f the body is lost), disability (im pedes on ability
to carry daily functions including chewing and speaking), and handicap (em barrassm ent o f
m eeting people due to dentures) (88).
D iscom fort &. pain
Disability » *
D is e a s e — ^ Im pairm ent ^ ► H andic ap
Functional limitation
F^ychologi<al
Sodd
F i g u r e 1-7: C o n c e p t u a l m o d e l f o r m e a s u r i n g o r a l h e a l t h - l . o c k e r . f ‘)88
