paper

Prevalence of xerostomia and hyposalivation and their association with quality of life in elderly patients in dependence on dental status and prosthetic rehabilitation: A pilot study

Sebastian Hahnel a,*, Simone Schwarz a, Florian Zeman b, Lina Schäfer a, Michael Behr a

a Department of Prosthodontics, Regensburg University Medical Center, Regensburg, Germany b Centre for Clinical Trials, Regensburg University Medical Center, Regensburg, Germany

j o u r n a l o f d e n t i s t r y 4 2 ( 2 0 1 4 ) 6 6 4 – 6 7 0

a r t i c l e i n f o

Article history:

Received 23 September 2013

Received in revised form

4 February 2014

Accepted 6 March 2014

Keywords:

Xerostomia

Hyposalivation

Quality of life

a b s t r a c t

Objectives: The aims of this pilot study were to investigate the prevalence of xerostomia and

hyposalivation and their impact on quality of life in a cohort of elderly patients including

dental status and the character of potential prosthetic restorations as independent vari-

ables.

Methods: Patients aged 60 years or older without any objective or subjective need for

prosthodontic treatment taking part in a regular recall programme were included in the

trial. Quality of life was assessed using the German version of the GOHAI; prevalence and

severity of xerostomia was investigated using the shortened version of the Xerostomia

Inventory (XI). Stimulated salivary flow rate was determined using a sialometric approach.

Dental status and the character of prosthetic restorations (no/fixed restorations and re-

movable but tooth-supported dentures vs. gum-supported dentures) were assessed in a

clinical examination by experienced dentists specialized in prosthodontic treatment.

Results: A total of 68 patients were included in the trial; a prevalence of xerostomia of 16%

and a prevalence of hyposalivation of 31% were identified. The quality of life in the study

cohort decreased significantly as a function of xerostomia severity but not salivary flow;

moreover, a significant impact of the number of teeth/implants in the upper jaw and the

presence of gum-supported dentures in both jaws on GOHAI scores could be identified.

Conclusions: Within the limitations of a pilot study, the results support the assumption that

the quality of life in elderly patients is particularly related to their subjective perception of

xerostomia. A decline in salivary flow, the dental status and the character of prosthetic

restorations appear to play a subordinate role for the quality of life in elderly patients.

Clinical significance: The quality of life in elderly patients may be severely diminished due to

an increased subjective perception of dry mouth. Dental treatment should focus on allevi-

ating xerostomia, whereas the impact of dental status and prosthetic restoration appear to

be subordinate.

# 2014 Elsevier Ltd. All rights reserved.

* Corresponding author at: Department of Prosthodontics, Regensburg University Medical Center, 93042 Regensburg, Germany. Tel.: +49 9419446059; fax: +49 9419446171.

E-mail address: [email protected] (S. Hahnel).

Available online at www.sciencedirect.com

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journal homepage: www.intl.elsevierhealth.com/journals/jden

http://dx.doi.org/10.1016/j.jdent.2014.03.003 0300-5712/# 2014 Elsevier Ltd. All rights reserved.

j o u r n a l o f d e n t i s t r y 4 2 ( 2 0 1 4 ) 6 6 4 – 6 7 0 665

1. Introduction

Numerous people suffer from dry mouth, and previous

epidemiological studies highlighted that its prevalence even

increases with age.1,2 In fact, in patients older than 60 years, it

has been estimated that by far more than 30% suffer from dry

mouth in dependence on the methodology applied for its

estimation,1,3,4 whereas the overall prevalence ranges be-

tween 7% and 29%.5,6 The correlation between the prevalence

of dry mouth and age is – in many causes – caused by the

consumption of xerogenic drugs affecting either perception or

secretion of saliva; other causes of ‘‘dry mouth’’ in elderly

patients include autoimmune diseases or radiation therapy of

malignancies. A decreasing production of saliva by the

salivary glands with increasing age is, however, still contro-

versially discussed.

Although numerous studies investigated the prevalence of

‘‘dry mouth’’ in elderly patients, only very few of them

employed a scientifically sound approach towards the

epidemiological evaluation of dry mouth.7 The terms xerosto-

mia and hyposalivation, which may be regarded as the

scientifically correct definitions of the subjective (xerostomia)8

and objective (hyposalivation) component of dry mouth, are

frequently employed as synonyms. Patients suffering from

xerostomia do not necessarily have hyposalivation,9 which

underlines that both the subjective and the objective

implications of dry mouth need to be determined in a

scientifically valid approach. For the determination of xer-

ostomia as the subjective perception of dry mouth, a

questionnaire labelled Xerostomia Inventory has been intro-

duced in the recent years,9,10 which was actually the first

scientifically validated tool to investigate the prevalence of

xerostomia. For the analysis of hyposalivation, however, the

measurement of salivary flow rate is commonly accepted as a

simple and reproducible means to determinate either unsti-

mulated or stimulated salivary flow.

The conventional wisdom is that both xerostomia and

hyposalivation may limit the quality of life of the affected

individuals. In elderly patients, previous studies have identi-

fied problems with daily routine as the most frequent

complaint associated with xerostomia, including problems

with speaking, chewing and biting.4,11 However, the character

and quality of prosthetic restorations and their relation to the

quality of life in patients suffering from xerostomia and/or

hyposalivation have almost been ignored. Particularly remov-

able denture prostheses cover the marginal and gingival areas

of the toothless jaw areas and, in dependence of the number of

residual abutment teeth or implants, require saliva as a

lubricant and agent for denture retention. The latest national

study on oral health issues in Germany revealed that complete

dentures are worn by more than 22% of the persons older than

65 years,12 which indicates that prosthetic rehabilitation of

patients with removable denture prostheses is still common.

With regard to the diminished availability of saliva in patients

with hyposalivation, it can be controversially discussed

whether these patients have a reduced quality of life in

comparison to patients with no or fixed dentures, and also

whether it should be recommended to avoid supplying these

patients with removable prostheses at all. Although the

authors of a recent review on this topic could not identify

sufficient scientific evidence for this assumption as a result of

the lack of clinical studies,13 it is likely that particularly in

patients suffering from either xerostomia or hyposalivation or

both, the number of residual teeth and the character of a

prosthetic restoration impacts their quality of life.

The primary aim of this clinical study was to elucidate the

prevalence of xerostomia and hyposalivation in a cohort of

elderly patients taking part in a regular recall programme and to

investigate the impact of xerostomia severity and salivary flow

on their oral health-related quality of life. The primary study

hypothesis was that the quality of life diminishes with an

increased perception of xerostomia and decreased salivary

flow. In addition to that, dental status and character of potential

prosthetic restorations were included as independent variables

in regression analyses, as we hypothesized that the quality of

life in patients wearing removable or gum-supported dentures

is lower than in patients with no or fixed prosthetic restorations

or tooth-supported removable restorations.

2. Materials and methods

2.1. Study design

The study was performed at the Department of Prosthodontics

of the University Medical Center Regensburg, Germany,

between January and December 2012. Patients aged 60 years

or older, who took part in a regular recall programme offered by

the Department of Prosthodontics and had not received

prosthodontic treatment for at least 6 months, were asked to

participate in the study. Patients suffering from dementia or

temporomandibular disorders were excluded, as were patients

consuming drugs or saliva substitutes for alleviating xerosto-

mia or hyposalivation. Acquisition of data was performed at a

single occasion during a regular recall appointment. All patients

were examined by an experienced dentist specialized in

prosthodontics; only patients with no objective need for any

prosthetic treatment were included in the study.

The study design was approved by the local ethics

committee of the University of Regensburg (no. 11-101-

0315). All patients gave their written consent to participate

in the study.

2.2. Determination of quality of life

Quality of life was determined employing the German version

of the Geriatric Oral Health Assessment Index (GOHAI).14,15 Data

were collected using a Likert-type scale. Each item in the

GOHAI had a scoring range from 1 to 5, corresponding with

‘‘never’’, ‘‘seldom’’, ‘‘occasionally’’, ‘‘frequently’’ and ‘‘very

often’’. The participating patients’ responses to the items were

summed up; high GOHAI sums correspond to lower quality of

life. Cronbach’s alpha indicated an internal consistency of .64

for the GOHAI data.

2.3. Assessment of xerostomia

Xerostomia as the subjective perception of dry mouth

was assessed using the shortened Xerostomia Inventory

j o u r n a l o f d e n t i s t r y 4 2 ( 2 0 1 4 ) 6 6 4 – 6 7 0666

questionnaire introduced by Thomson et al.10, including the

following items:

(1) My mouth feels dry when eating a meal.

(2) My mouth feels dry.

(3) I have difficulty in eating dry foods.

(4) I have difficulties swallowing certain foods.

(5) My lips feel dry.

The questionnaire was translated into a German version by

the supervising dentist (S.H.). Data were collected using a

Likert-type scale. Each item in the Xerostomia Inventory had a

scoring range from 1 to 3, corresponding with ‘‘never’’,

‘‘occasionally’’, and ‘‘often’’. The participating patients’

responses to the items were summed up; high sums

corresponded to a pronounced perception of xerostomia.

Cronbach’s alpha indicated an internal consistency of .75 for

the XI data.

2.4. Determination of salivary flow

Assessment of hyposalivation was performed prior to any

dental examination or prophylaxis treatment to exclude

potential impacts on salivary flow. Salivary flow rate was

determined using a sialometric approach. Patients were asked

to rinse their mouth with tap water prior to the determination

of salivary flow. After expectoration, secretion of saliva was

stimulated by chewing on a commercially available paraffin

pellet (CRT Paraffin, Ivoclar Vivadent, Schaan, Liechtenstein)

with a frequency of 1/s. Patients were asked to expectorate the

saliva collected during the first 30 s into the spittoon bowl of

the dental unit; subsequently, stimulated saliva was collected

by expectoration into a tube for a period of 5 min. Stimulated

salivary flow rate was determined in ml/min.

2.5. Dental status

Dental status was determined in a clinical examination by an

experienced dentist specialized in prosthetic dentistry; the

number of teeth in each jaw was recorded. Dental implants

were treated as natural teeth. Patients without any prosthetic

restorations and those supplied with crowns or fixed partial

dentures were merged into a single subgroup. For patients

with removable dentures, the localization of the denture in

either one or both jaws was recorded. Furthermore, it was

determined whether prosthetic restorations were tooth/

implant-supported (i.e. patients with no prosthetic restora-

tion, patients with crowns and fixed partial dentures, patients

with removable dentures fixed to at least four teeth) or gum-

supported (patients with removable dentures supported by

less than four teeth, patients with complete dentures).

2.6. Statistical analysis

No calculation of sample sizes has been performed due to the

lack of values required for proper calculation. Patient

characteristics are summarized as means (SD) and range

(minimum to maximum) for continuous variables, as well as

frequency counts and percentages for categorical data.

Patients with a stimulated salivary flow rate �0.7 ml/min

were regarded as patients with hyposalivation, and patients

with an XI sum score �10 were regarded as patients with xerostomia. Categorical data were compared by an exact

unconditional test using Pearson’s statistic. Simple and

multiple linear regression models were calculated to assess

the effect of clinical parameters and XI score as independent

variables on the GOHAI score as dependent variable. Multi-

collinearity was assessed by the variance inflation factor (VIF);

a VIF >5 was considered as high multicollinearity. The level of

significance (a) was set to 0.05. Statistical analysis was

performed using SPSS 21.0 for Windows (SPSS Statistics, IBM).

3. Results

Table 1 shows patient data, GOHAI, and XI scores and

stimulated salivary flow rates of the entire cohort and patients

with xerostomia and hyposalivation, Table 2 depicts the

analysis of the categorical data by displaying the percentage of

study participants responding ‘‘occasionally’’, ‘‘fairly often’’,

or ‘‘very often’’ to the various GOHAI items, and Table 3 shows

effect sizes according to mean GOHAI scores for patients with

and without xerostomia and hyposalivation.

A prevalence of xerostomia of 16% (patients with XI scores

�10) and a prevalence of hyposalivation of 31% (patients with stimulated salivary flow rate �0.7 ml/min) were identified.

All predictors (XI, salivary flow rate, number of teeth/

implants in the upper and lower jaw, presence of removable

dentures, tooth/implant- or gum-support of prosthetic

restorations) of the GOHAI score were analyzed using simple

linear regression models. The only significant predictor of

GOHAI was the XI score (R2 = 0.41, B = �1.95 (95% CI: �2.53, �1.38), p < 0.0001) (Table 4), with a B value of �1.95 indicating that a one unit increase in the XI score corresponds to a

decrease of the GOHAI score to almost 2 units.

By adding all variables into a multiple linear regression

model, the number of teeth/implants in the upper jaw and the

presence of gum-supported dentures in both jaws had a

significant influence on GOHAI score next to XI. With an R2

value of 0.48, almost 50% of the GOHAI variance could be

explained by all variables (Table 5). There were no multi-

collinearity issues according to the VIF.

4. Discussion

The results of this clinical study suggest only partial

acceptance of the primary research hypothesis, indicating

that the quality of life in elderly patients decreases as a

function of an increased subjective perception of dry mouth

but not stimulated salivary flow.

The results of numerous of the vast amount of studies

dealing with the prevalence of xerostomia in elderly patients

have to be interpreted with caution, as until the publication of

the Xerostomia Inventory questionnaire in its original and –

more recently – shortened (SXI-D) version,9,10 there were no

commonly accepted tools for evaluating the subjective

sensation of dry mouth on the basis of a scientifically

approved approach. In the cohort investigated in this study,

the mean SXI-D sums ranged around 8 and were similar to the

Table 1 – Survey on the clinical data gathered for the entire cohort and patients with hyposalivation and xerostomia.

Entire cohort Patients with hyposalivation Patients with xerostomia

N 68 21 11

Female/Male 49/19 16/5 9/2

Mean age (SD; range) 68.6 (6.5; 60–93) 68.3 (5.9; 61–81) 69.0 (4.1; 63–75)

Mean GOHAI score (SD) 50.7 (7.4) 50.5 (6.9) 41.0 (7.9)

Mean XI score (SD) 7.5 (2.4) 8.6 (3.1) 12.1 (1.8)

Mean stimulated salivary flow rate, ml/min (SD) 1.1 (0.6) 0.5 (0.1) 0.7 (0.5)

Mean N teeth/implants (SD; range)

Upper jaw 7.2 (5.0; 0–14) 7.8 (4.9; 0–14) 5.5 (5.2; 0–14)

Lower jaw 8.3 (4.7; 0–14) 7.6 (4.8; 0–14) 5.2 (5.3; 0–14)

Prosthetic construction

No/crowns/fixed partial dentures 26 (38.2%) 8 (38.1%) 2 (18.2%)

Removable denture upper jaw 7 (10.3%) 1 (4.8%) 1 (9.1%)

Removable denture lower jaw 7 (10.3%) 2 (9.5%) 3 (27.3%)

Removable dentures both jaws 28 (41.2%) 10 (47.6%) 5 (45.5%)

Denture support

Tooth/implant 45 (66.2%) 13 (61.9%) 5 (45.5%)

Gum-supported in one jaw 9 (13.2%) 4 (19.0%) 2 (18.2%)

Gum-supported in both jaws 14 (20.6%) 4 (19.0%) 4 (36.4%)

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SXI-D scores reported for larger cohorts of elderly patients in

previous studies.10 With a Cronbach’s alpha of .75, XI data

showed a satisfactory internal consistency.16 However, al-

though interpretation of SXI-D scores allows an estimation of

the degree of xerostomia, no threshold value for the percep-

tion of xerostomia has yet been determined, which still makes

it difficult to estimate its overall prevalence. As SXI-D sums

may range from 5 (lowest perception of xerostomia) to 15

(highest), the authors regarded patients with SXI-D sums

equal or higher than 10, representing patients with the top 50%

SXI-D sum scores, as patients with xerostomia. As a result, a

xerostomia prevalence of 16% was identified, which was in the

lower range of xerostomia prevalences in elderly patients that

had been reported in previous studies.1,2,4,9,11,17–20 Most likely,

this phenomenon can be attributed to the application of a

scientifically defined questionnaire rather than a simple

standard question such as ‘‘How often does your mouth feel

dry?’’, and the rigid criteria applied for the definition of a

Table 2 – Percent of study participants responding ‘‘occasiona

GOHAI items Entire cohort Hy

(n = 68) �0.7 ml/min (n = 21, 31%)

Trouble biting/chewing food 31 (45.6%) 8 (38.1%)

Swallow without problems 60 (88.2%) 16 (76.2%)

Prevented from speaking 9 (13.3%) 4 (19.0%)

Eat without discomfort 61 (89.7%) 20 (95.2%)

Use medication to relieve pain 7 (10.3%) 2 (9.5%)

Teeth, gums sensitive to hot/cold 17 (25%) 6 (28.5%)

Happy with appearance 62 (91.2%) 20 (95.2%)

Worried or concerned 33 (48.5%) 9 (42.9%)

Nervous or self-conscious 19 (27.9%) 5 (23.8%)

Uncomfortable eating in front of people 15 (22.1%) 3 (14.3%)

Limit kinds or amounts of food 16 (23.4%) 8 (38.1%)

Limit contact with others 4 (5.8%) 2 (9.5%)

Bold letters refer to statistically significant values. * p-Values calculated according to an exact unconditional test using Pea

xerostomia threshold based on SXI-D sum score values. As

patients consuming drugs or saliva substitutes for the

alleviation of xerostomia and hyposalivation were excluded

from participating in the study, it might be possible that this

procedure caused a selection bias, resulting in an underesti-

mation of the prevalence of xerostomia and hyposalivation.

Although no information about the absolute number of

patients excluded for this reason is available, the authors

discussed this circumstance thoroughly and agree that the

number of patients excluded from the trial due to the

consumption of drugs or saliva substitutes is negligible.

Treatment of xerostomia and hyposalivation in elderly

patients with saliva substitutes and drugs is not common in

Germany and, in very most cases, restricted to patients

suffering from radiation-induced xerostomia and hyposaliva-

tion, which were not the typical patient included in the trial. In

addition to that, the patient cohort analyzed in this study was

very distinct from those in previous investigations, as merely

lly’’, ‘‘fairly often’’, or ‘‘very often’’ to each GOHAI item.

posalivation Xerostomia

>0.7 ml/min (n = 47, 69%)

p-Value* XI < 10 (n = 57, 84%)

XI � 10 (n = 11, 16%)

p-Value*

8 (17.0%) 0.06 17 (29.8%) 10 (90.9%) 0.001

44 (93.6%) 0.039 50 (87.7%) 10 (90.9%) 0.88

5 (10.6%) 0.41 5 (8.8%) 4 (36.4%) 0.014

41 (87.2%) 0.34 51 (89.4%) 10 (90.9%) 0.93

5 (10.6%) 0.91 11 (19.3%) 5 (45.5%) 0.08

11 (23.4%) 0.75 12 (21.1%) 5 (45.5%) 0.09

42 (89.4%) 0.48 52 (91.2%) 10 (90.9%) 1.00

24 (51.1%) 0.60 23 (40.4%) 10 (90.9%) 0.009

14 (29.8%) 0.73 11 (19.3%) 8 (72.7%) 0.001

12 (25.5%) 0.32 26 (45.6%) 10 (90.9%) 0.013

8 (17.0%) 0.06 7 (12.3%) 9 (81.8%) <0.001

2 (4.2%) 0.44 3 (5.3%) 7 (63.6%) <0.001

rson’s statistic.

Table 3 – Effect sizes for the categorical GOHAI data for patients with and without hyposalivation and with and without xerostomia.

Hyposalivation Xerostomia

�0.7 ml/min >0.7 ml/min XI < 10 XI � 10 Mean GOHAI (SD) 50.5 (6.9) 50.8 (7.7) 52.6 (5.6) 41.0 (7.9)

Cohen’s d 0.04 1.69

p-Value* 0.893 <0.001

Bold letters refer to statistically significant values. * Calculated by Student’s t-test.

Table 4 – Simple linear regression models on GOHAI score.

Predictors B (95% CI) p-Value R2

XI �1.95 (�2.53, �1.38) <0.001 0.41 Salivary flow rate 2.48 (�0.49, 5.45) 0.100 0.04 Number of teeth/implants in the upper jaw 0.17 (�0.19, 0.53) 0.349 0.01 Number of teeth/implants in the lower jaw 0.29 (�0.09, 0.67) 0.133 0.03

Presence of removable dentures

One jaw �2.17 (�7.09, 2.76) 0.384 0.01 Both jaws �0.38 (�4.43, 3.67) 0.852

Tooth/implant- or gum-support of prosthetic restorations

One �2.42 (�7.85, 3.01) 0.376 0.01 Both 0.24 (�4.31, 4.79) 0.918

Bold letters refer to statistically significant values.

j o u r n a l o f d e n t i s t r y 4 2 ( 2 0 1 4 ) 6 6 4 – 6 7 0668

elderly patients taking part in a regular dental recall programme

offered by the ambulatory Department of Prosthetic Dentistry at

the University Medical Center Regensburg and without any

subjective and objective need for prosthetic intervention were

included. With regard to this aspect, numerous of the previous

studies were conducted in patients living in nursing homes, and

only very little attention has been paid to the dental status or the

condition of prosthetic restorations.

SXI-D sum score was the only highly significant predictor of

the GOHAI in both regression models, and high values for the

regression coefficient B and the R2 value further underline the

relevance of the subjective sensation of dry mouth on elderly

patients’ quality of life. This phenomenon becomes particularly

Table 5 – Multiple linear regression model on GOHAI score.

Predictors B (95% CI) p-value

XI �1.99 (�2.64, �1.33) <0.001 Salivary flow rate �0.49 (�3.02, 2.04) 0.702 Number of teeth/implants

in the upper jaw

0.57 (0.053, 1.09) 0.031

Number of teeth/implants

in the lower jaw

0.36 (�0.23, 0.96) 0.224

Presence of removable dentures

One jaw 2.34 (�2.33, 7.02) 0.320 Both jaws 3.24 (�3.04, 9.52) 0.306

Tooth/implant- or gum-support

of prosthetic restorations

One jaw 4.34 (�0.98, 9.65) 0.108 Both jaws 7.32 (1.31, 13.32) 0.018

Model summary: R2 ¼ 0:48; R2corr ¼ 0:41; F ¼ 6:75

Bold letters refer to statistically significant values.

obvious in the high effect sizes observed for the categorical

GOHAI scores and the significantly higher percentage of

patients with an SXI-D sum score equal or higher than 10

responding ‘‘occasionally’’, ‘‘fairly often’’, and ‘‘very often’’ to

the GOHAI items analyzing functional limitations and psycho-

logical and behavioural impacts in comparison to patients with

an SXI-D sum score lower than 10. However, with a Cronbach’s

alpha of .64 GOHAI data yielded rather low internal consistency

in the present study and should thus be interpreted with

caution. It should be borne in mind that both XI and GOHAI

assess functional components such as difficulties in eating or

swallowing, which indicates that both tools overlap at least in

parts. However, the XI is the only validated tool available for the

determination of xerostomia, and the GOHAI is a measure that

has been designed particularly for the evaluation oral health

related quality of life in elderly patients,21 which were the

reasons why the authors chose these questionnaires and

accepted the overlapping components of the GOHAI and the XI.

In the present study, a commonly accepted threshold

stimulated salivary flow rate of 0.7 ml/min was used for

identifying patients with hyposalivation.22 Despite of the high

hyposalivation prevalence of 31%, stimulated salivary flow rate

was not a significant predictor of the GOHAI neither in the

simple nor the multiple linear regression models, indicating

that elderly patients with hyposalivation do not per se suffer

from a limited quality of life. This observation becomes

particularly obvious in the fact that for the categorical GOHAI

data, effect sizes between patients with and without hyposa-

livation were very low and the only significant difference

identified between patients with hyposalivation and those

without was for the GOHAI item ‘‘swallow without problems’’,

where patients with hyposalivation responded significantly

less often ‘‘occasionally’’, ‘‘fairly often’’, and ‘‘very often’’. There

are only very few clinical studies investigating both xerostomia

j o u r n a l o f d e n t i s t r y 4 2 ( 2 0 1 4 ) 6 6 4 – 6 7 0 669

and hyposalivation in elderly patients. The prevalence of

hyposalivation identified in this study was markedly higher

than in other recently published studies,23,24 which is most

likely due to differences in study methodology and the

hyposalivation thresholds applied. However, the high preva-

lence of hyposalivation in this cohort indicates that dentists

should pay particular attention to the clinical side effects

associated with hyposalivation such as caries or fungal

infections of the oral cavity.

With regard to the secondary research hypothesis, simple

linear regression models identified no significant influence of

the dental status and the character of a prosthetic restoration

on the GOHAI. However, using the multiple linear regression

models, we identified a significant impact of the number of

teeth/implants in the upper jaw and the presence of gum-

supported prosthetic restorations in both jaws. With regard to

these results, it has frequently been proven that both

character and quality of a prosthetic restoration may

significantly impact patients’ quality of life.25,26 The conven-

tional wisdom is that with a decreasing number of residual

teeth or implants, removable denture prostheses need to

transfer chewing forces to toothless jaw areas. As a result, it is

clear that the relevance of saliva for denture retention,

lubrication and comfort increases as a function of a decreasing

number of supporting teeth and implants. It has been shown

that the insertion of implants may significantly improve

quality of life in patients that had originally been supplied with

conventional denture prostheses.27 To the knowledge of the

authors, the present study is actually the first investigation

that attempts to analyze the impact of xerostomia, hyposa-

livation, dental status and character of prosthetic restorations

on the quality of life in elderly patients. Due to the strict

inclusion criteria – only elderly patients with subjectively and

objectively sufficient prosthetic restorations taking part in a

regular recall programme – and the heterogeneity of the study

population with regard to the prosthetic constructions, the

authors were fully aware that the statistical power that could

be achieved in this respect could only meet the levels of a pilot

trial. As the overall number of patients with xerostomia

(n = 11) or hyposalivation (n = 21) in the study cohort was low,

the authors refrained from performing subgroup analyses to

investigate correlations between quality of life, dental status,

and the character of prosthetic restorations in patients with

xerostomia or hyposalivation, but included these issues as

independent variables into simple and multiple linear regres-

sion models. The results indicate that xerostomia is a

significantly better predictor of the quality of life in elderly

patients than the dental status or the character of prosthetic

restorations. Nevertheless, data showed that both the number

of teeth/implants in the upper jaw and the presence of gum-

supported dentures in both jaws may significantly impair the

quality of life in elderly patients, which supports the conven-

tional wisdom currently available. Thus, the presence of

removable dentures or gum-supported dentures in only one

jaw does not a priori impair the quality of life in elderly patients.

Although almost 50% of the GOHAI could be explained by all

variables in the multiple linear regression model, it is very

wishful that larger follow-up studies in simplified patient

cohorts and multi-centre studies are performed to corroborate

the results of the present study and to elucidate, whether

elderly patients suffering from xerostomia and/or hyposaliva-

tion wearing gum-supported denture prostheses have an

impaired quality of life in comparison to patients with tooth-

or implant-supported prosthetic restorations.

5. Conclusions

The results of this pilot study underline the relevance of the

subjective sensation of dry mouth on the quality of life of

elderly patients and indicate that effective strategies need to

be developed to alleviate xerostomia in elderly patients.

Within the limitations of this pilot trial, the results indicate

that the presence of removable dentures is not a priori

correlated to lower quality of life in comparison to patients

without removable prosthetic restorations or tooth-supported

dentures. Follow-up studies in simplified cohorts and multi-

centre studies are wishful to corroborate these findings.

r e f e r e n c e s

1. Nederfors T, Isaksson R, Mörnstad H, Dahlöf C. Prevalence of perceived symptoms of dry mouth in an adult Swedish population – relation to age, sex and pharmacotherapy. Community Dentistry and Oral Epidemiology 1997;25:211–6.

2. Johansson AK, Johansson A, Unell L, Ekbäck G, Ordell S, Carlsson GE. Self-reported dry mouth in Swedish population samples aged 50, 65 and 75 years. Gerodontology 2012;29:e107–15.

3. Ship JA, Pillemer SR, Baum BJ. Xerostomia and the geriatric patient. Journal of the American Geriatrics Society 2002; 50:535–43.

4. Gerdin EW, Einarson S, Jonsson M, Aronsson K, Johansson I. Impact of dry mouth conditions on oral health-related quality of life in older people. Gerodontology 2005;22:219–26.

5. Guggenheimer J, F Moore P.A.. Xerostomia – etiology, recognition and treatment. Journal of the American Dental Association 2003;134:61–9.

6. Villa A, Polimeni A, Strohmenger L, Cicciù D, Gherlone E, Abati S. Dental patients’ self-reports of xerostomia and associated risk factors. Journal of the American Dental Association 2011;142:811–6.

7. Quandt SA, Savoca MR, Leng X, Chen H, Bell RA, Gilbert GH, et al. Dry mouth and dietary quality in older adults in North Carolina. Journal of the American Geriatrics Society 2011; 59:439–45.

8. Davies AN. The management of xerostomia: a review. European Journal of Cancer Care 1997;6:209–14.

9. Thomson WM, Chalmers JM, Spencer AJ, Williams SM. The Xerostomia Inventory: a multi-item approach to measuring dry mouth. Community Dental Health 1999;16:12–7.

10. Thomson WM, van der Putten GJ, de Baat C, Ikebe K, Matsuda KI, Enoki K, et al. Shortening the xerostomia inventory. Oral Surgery Oral Medicine Oral Pathology Oral Radiology and Endodontology 2011;112:322–7.

11. Locker D. Dental status, xerostomia and the oral health- related quality of life of an elderly institutionalized population. Special Care in Dentistry 2003;23:86–93.

12. Micheelis W, Schiffner U. Vierte deutsche Mundgesundheitsstudie (DMS IV). Köln: Deutscher Ärzte- Verlag; 2006: 19.

13. Turner M, Jahangiri L, Ship JA. Hyposalivation, xerostomia and the complete denture: a systematic review. Journal of the American Dental Association 2008;139:146–50.

j o u r n a l o f d e n t i s t r y 4 2 ( 2 0 1 4 ) 6 6 4 – 6 7 0670

14. Atchison KA, Dolan TA. Development of the Geriatric Oral Health Assessment Index. Journal of Dental Education 1990;54:680–7.

15. Hassel AJ, Rolko C, Koke U, Leisen J, Rammelsberg P. A German version of the GOHAI. Community Dentistry and Oral Epidemiology 2008;36:34–42.

16. Bland JM, Altman DG. Cronbach’s alpha. British Medical Journal 1997;314:572.

17. Österberg T, Landahl S, Hedegard B. Salivary flow, saliva, pH and buffering capacity in 70-year-old men and women. Journal of Oral Rehabilitation 1984;11:157–70.

18. Gilbert GH, Heft MW, Ducan RP. Mouth dryness as reported by older Floridians. Community Dentistry and Oral Epidemiology 1993;21:390–7.

19. Närhi TO. Prevalence of subjective feelings of dry mouth in the elderly. Journal of Dental Research 1994;73:20–5.

20. Hochberg MC, Tielsch J, Munoz B, Bandeen-Roche K, West SK, Schein OD. Prevalence of symptoms of dry mouth and their relationship to saliva production in community dwelling elderly: the SEE project. Journal of Rheumatology 1998;25:486–91.

21. Locker D, Matear D, Stephens M, Lawrence H, Payne B. Comparison of the GOHAI and OHIP-14 as measures of the oral-health related quality of life of the elderly. Community Dentistry and Oral Epidemiology 2001;29:373–81.

22. Laaksonen M, Ramseier A, Rovò A, Jensen SB, Raber- Durlacher JE, Zitzmann NU, et al. Longitudinal assessment

of hematopoietic stem cell transplantation and hyposalivation. Journal of Dental Research 2011;90:1177–82.

23. Ikebe K, Matsuda K, Morii K, Wada M, Hazeyama T, Nokubi T, et al. Impact of dry mouth and hyposalivation on oral- health related quality of life of elderly patients. Oral Surgery Oral Medicine Oral Pathology Oral Radiology and Endodontology 2007;103:216–22.

24. Ohara Y, Hirano H, Yoshida H, Obuchi S, Ihara K, Fujiwara Y, et al. Prevalence and factors associated with xerostomia and hyposalivation among community-dwelling older people in Japan. Gerodontology 2013. http://dx.doi.org/10.1111/ ger.12101.

25. Montero J, Castillo-Oyagüe R, Lynch CD, Albaladejo A, Castano A. Self-perceived changes in oral health-related quality of life after receiving different types of conventional prosthetic treatments: a cohort follow-up study. Journal of Dentistry 2013;41:493–503.

26. Vogel R, Smith-Palmer J, Valentine W. Evaluating the health economic implications and cost-effectiveness of dental implants: a literature review. International Journal of Oral and Maxillofacial Implants 2013;28:343–56.

27. Harris D, Höfer S, O’Boyle CA, Sheridan S, Marley J, Benington IC, et al. A comparison of implant-retained mandibular overdentures and conventional dentures on quality of life in edentulous patients: a randomized, prospective, within-subject controlled clinical trial. Clinical Oral Implants Research 2013;24:96–103.

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