Abstract
Objective: To determine the impact of periodontal disease and periodontal therapy on oral health-related quality of life using the German version of the Oral Health Impact Profile, taking into account the possible effects of age, gender and socioeconomic factors. Methods: This is a study of 93 patients of both sexes aged 27–74 years. The sample included 82 patients with a diagnosis of periodontal diseases, 11 patients without periodontitis (control group). All patients used the German 14-item version of the Oral Health Impact Profile, as well as a socioeconomic and demographic questionnaire. This was used to assess oral health-related quality of life issues. The questionnaire and clinical inspection were done before and 6–8 weeks after the periodontal treatment. Results: Periodontal diseases have an effect on oral health-related quality of life issues. Scores for the German 14-item version of the Oral Health Impact Profile were associated with severity of periodontal diseases, sex, age, oral hygiene and smoking habits. The highest scores included those patients with a probing pocket depth of >7 mm. The median score of these patients was reduced from 14.4 at baseline to 5.5 after treatment (P = 0.007). These patients perceived physical, social and psychological changes in oral health-related quality of life after periodontal therapy. Median OHIP-G-14 scores were reduced from 6.3 at baseline to 4.8 6–8 weeks after treatment (P < 0.001). The number of teeth with a probing pocket depth >3 mm could be reduced from 76.0% at baseline to 27.6% after treatment. Conclusion: The association between periodontal diseases and the oral health-related quality of life was determined. The positive effect of the periodontal treatment on the oral health related quality of life was also shown and was most pronounced for patients with a probing pocket depth of >7 mm.
Key words: Periodontitis, periodontal diseases, oral health, quality of life, periodontal treatment, socioeconomic factors
INTRODUCTION
Periodontal diseases are a major oral health problem, as they are still the main reason for tooth loss in industrialised countries. It has been shown that the rate of tooth loss can be decreased by new forms of therapy and prophylactic dental measures1. At the same time the increase in periodontal diseases has become an important issue.
The fourth German Oral Health Study (DMS IV) of 2005 is a representative cross-sectional study of the German population. In Germany 35–44-year-olds (adults) and 65–74-year-olds (senior citizens) are especially affected by an increase in periodontal diseases.
In comparison with the previous study (DMS III 1997)2 there has been an increase in the community periodontal index (CPI) [score of 3 (pocket depth 4–5 mm) and 4 (pocket depth >5 mm)] for the 35–44-year-old age-group from 46.3% (DMS III) to 73.2% (DMS IV). Similarly senior citizens had a CPI score of 3 and 4 in the DMS III of 64.1% but 8 years later, in the DMS IV, the score was of 87.8%. This rapid increase in periodontal diseases within the last eight years between these two studies was less severe when the probing pocket depth was assessed.
In clinical studies, clinical parameters, such as the decrease in pocket depth and bleeding index scores, are most often used as therapeutic outcomes. The impact of oral health on the quality of life and on periodontal therapy on oral health-related quality of life (OHQoL) is seldom the focus of such studies.
The term ‘quality of life’ is an important factor, which brings the patient and their view into the heart of consideration. ‘Quality of life’ is a multidimensional construct with no final definition.
The World Health Organisation (WHO) describe the quality of life as follows:
‘Quality of life is defined as an individual’s perception of their position in life in the context of the culture and value systems in which they live and relation to their goals, expectations, standards and concerns. It is a broad ranging concept affected in a complex way by the person’s physical health, psychological state, level of independence, social relationship and their relationship to salient features of their environment’ (WHO 1997)3.
The OHQoL focuses on this part of quality of life which is influenced by the stomatognathic system4. The OHQoL describes patients’ subjective experience of oral health and delivers information to complement objective clinical parameters.
A number of measuring instruments have been developed, in the form of questionnaires, for the assessment of OHQoL. Major aspects of OHQoL in these instruments are functional limitation, orofacial pain, dentofacial aesthetics and the psychosocial influence of oral health5.
The most common questionnaire for detecting the OHQoL is the Oral Health Impact Profile (OHIP). This was been developed in Australia by Slade & Spencer6 and included 49 questions. The OHIP was translated into German (OHIP-G) by John et al.7 and they also developed three short versions (with 5, 14 and 21 questions). The OHIP has been used in many countries, for example, in England, where toothless patients were restored with implant-stabilised or conventional complete dentures and were questioned about their OHQoL before and after treatment8. Larrson et al.9 used the Swedish version of the Oral Health Impact Profile (OHIP-S) for patients with craniomandibular dysfunctions. In their 2006 study, Ng & Leung10 examined the correlation between OHQoL and periodontal status. A total of 767 patients were questioned using the Chinese short version of the OHIP and it was determined that there was a statistically significant connection between OHQoL and periodontal disease.
The aim of this study was to investigate the effect of periodontal diseases and periodontal therapy on OHQoL, taking into account the possible effects of age, gender and socioeconomic factors.
METHODS
This study was carried out in full accordance with the World Medical Association Declaration of Helsinki. All patients were asked to give written consent to receive periodontal treatment. All patients were informed and asked verbally to complete written health questionnaires before and after the periodontal treatment. The periodontal treatment in the study was done according to the guidelines of the German Society of Periodontology and the Kassenzahnärztliche Bundesvereinigung (KZBV). The evaluation of the study was performed with a quality of life questionnaire, therefore no ethical board was involved.
The patients of a practice with symptoms of periodontal disease presented themselves for treatment in the years 2009 and 2010. A total of 93 patients participated in this study (35 males, 58 females, age range 27–74 years, mean 51 years). To be included in the study, patients had to be 18 years of age or older and have had no acute medical disease (including psychological disorders or mental problems) that might affect their ability to understand and/or to answer the questionnaire.
The procedure of the present study consisted of the following steps: initial diagnosis at baseline and patient information; hygiene period (supragingival scaling); subgingival scaling and root debridement under local anaesthesia; follow-up diagnosis 6–8 weeks after treatment.
Clinical parameters, such as probing pocket depth (PPD) and papillary bleeding index (PBI), were recorded at baseline and 6–8 weeks after treatment. The PPD is a clinical test to determine the coronoapical extension of the periodontal pocket. It defines the distance between marginal gingiva and most coronal periodontal fibres. The level of gingival inflammation was determined by the PBI11.
The impact of oral health on the patients’ quality of life was assessed using the OHIP-G-147. The OHIP-G-14 includes 14 questions with the seven domains: functional limitation, physical pain, psychological discomfort, psychological disability, physical disability, social disability and handicap. The questionnaire was answered at baseline (before subgingival scaling) after treatment (6–8 weeks after subgingival scaling). The OHIP has been shown to be reliable12 and sensitive to changes13.
In addition, the participants were questioned about ‘gum bleeding’ and ‘unpleasant taste in mouth’. After treatment, the participants could describe changes in their oral health using the questionnaire (answer options were: ‘big improvement’, ‘small improvement’, ‘equal’, ‘small deterioration’, ‘big deterioration’) and possible positive effects after treatment, such as ‘better feeling in mouth’ or ‘better breath’.
Other contents of the questionnaire were:
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•
Tooth-cleaning frequency
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Use of dental service
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•
Consumption of tobacco
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Sociodemographic factors (age, gender, school education).
The patients were assigned into groups depending on the severity of the periodontitis measured by the baseline PPD and the CPI score: control group (PPD < 4 mm, CPI score 0–2), patients with CPI score of 3 (PPD = 4–5 mm) and patients with CPI score of 4 (PPD > 5 mm). The group with CPI score of 4 was subdivided into two parts: patients with PPD = 6–7 mm and patients with PPD > 7 mm.
Statistical analyses were performed using Microsoft Excel 2002, version 10.0. The data were analysed using Student t-test, with the significance level set as P < 0.05.
RESULTS
In total, 93 patients participated in the study. The study included a control group (n = 11) consisting of healthy volunteers with PPD < 4 mm (CPI score 0–2). A total of 82 participants diagnosed with periodontitis completed the whole process of periodontal therapy and completed the questionnaire at baseline and 6–8 weeks after treatment. Mean PPD at baseline was 4.0 mm. The mean age of the 93 patients was 51 years (range 27–74 years). The demographic characteristics of the study population are shown in Table 1. The level of school education was used as criterion for the social state. Nearly half of the population had finished the German High School or examinations or a university degree (high social status). About three-quarters of the patients used the dental services (regular dental visit for check-up/professional cleaning) and 18% of the subjects were smokers.
Table 1.
Demographic characteristics of the study population (n = 93)
| Demographic characteristics | n (%) |
|---|---|
| Gender | |
| Male | 35 (37.6) |
| Female | 58 (62.4) |
| Age (years) | |
| <45 | 25 (26.9) |
| 45-64 | 52 (55.9) |
| >64 | 16 (17.2) |
| Social state | |
| Low | 18 (19.3) |
| Medium | 29 (31.2) |
| High | 46 (49.5) |
| Oral hygiene | |
| Good | 48 (51.6) |
| Bad | 45 ( 48.4) |
| Tobacco consumption | |
| Yes | 17 (18.3) |
| No | 76 (81.7) |
| Use of dental services | |
| Control oriented | 63 (67.7) |
| Pain oriented | 30 (32.3) |
| Professional situation | |
| Currently not in employment | 5 (5.4) |
| Part-time working | 22 (23.7) |
| Full-time working | 42 (45.2) |
| Retired | 16 (17.2) |
| Housewife/househusband | 6 (6.5) |
| In education | 2 (2.2) |
Table 2 shows the therapeutic outcomes of periodontitis patients from baseline to 6–8 weeks after treatment, according to CPI score, gender, age and tobacco consumption. Mean PPD decreased significantly (P < 0.001) from 4.0 mm at baseline to 2.97 mm 6–8 weeks after treatment. The mean PBI dropped from 0.56 at baseline to 0.20 after treatment (P < 0.001). The mean PPD in the group with a CPI score of 4 declined from 4.3 mm at baseline to 3.1 mm after treatment (P < 0.001). In the patient group with CPI scores of 4 and pocket depths >7 mm the decrease of PPD and PBI was very high. In this group the mean PPD showed a reduction from 5.8 mm at baseline to 4.1 mm after treatment (P < 0.001) and the mean PBI significantly decreased from 0.82 at baseline to 0.19 after treatment (P < 0.001). In our treatment group smokers had a higher mean PPD (4.4 mm at baseline, 3.2 mm after treatment) than that of non-smokers (3.9 mm at baseline, 2.9 mm after treatment).
Table 2.
Mean probing pocket depth (PPD) and mean papillary bleeding index (PBI) of periodontitis patients (n = 82) at baseline and 6–8 weeks after treatment, according to community periodontal index (CPI) score, gender, age and tobacco consumption
| Mean PPD | Mean PBI | |||||
|---|---|---|---|---|---|---|
| At baseline | After treatment | P | At baseline | After treatment | P | |
| All periodontitis patients (n = 82) | 4.0 | 2.97 | P < 0.001* | 0.56 | 0.20 | P < 0.001* |
| CPI score | ||||||
| 3 (n = 30) | 3.4 | 2.7 | P < 0.001* | 0.55 | 0.21 | P < 0.001* |
| 4 (n = 52) | 4.3 | 3.1 | P < 0.001* | 0.55 | 0.19 | P < 0.001* |
| CPI score of 4 | ||||||
| PPD 6–7 mm (n = 41) | 3.9 | 2.9 | P < 0.001* | 0.47 | 0.19 | P < 0.001* |
| PPD >7 mm (n = 11) | 5.8 | 4.1 | P < 0.001* | 0.82 | 0.19 | P < 0.001* |
| Gender | ||||||
| Female (n = 54) | 4.0 | 3.0 | P < 0.001* | 0.57 | 0.22 | P < 0.001* |
| Male (n = 28) | 4.0 | 2.9 | P < 0.001* | 0.50 | 0.15 | P < 0.001* |
| Age | ||||||
| <45 years (n = 19) | 3.7 | 2.9 | P < 0.001* | 0.54 | 0.24 | P < 0.001* |
| 45-64 years (n = 47) | 4.1 | 3.0 | P < 0.001* | 0.57 | 0.19 | P < 0.001* |
| >64 years (n = 16) | 4.1 | 2.9 | P < 0.001* | 0.54 | 0.18 | P = 0.002* |
| Tobacco consumption | ||||||
| Yes (n = 16) | 4.4 | 3.2 | P = 0.002* | 0.50 | 0.10 | P < 0.001* |
| No (n = 66) | 3.9 | 2.9 | P < 0.001* | 0.56 | 0.21 | P < 0.001* |
Student t-test: *significant.
Figure 1 shows the mean scores for OHIP-G-14 of the control group and periodontitis patients from baseline to 6–8 weeks after treatment, according to CPI score, gender, age and tobacco consumption. The study results show that periodontitis has a statistically significant impact on individuals’ OHRQoL. The mean OHIP-G-14 score of the control group was 1.4 whereas patients with periodontal disease had a significantly higher mean score of 6.3 at baseline. The analysis also revealed that periodontitis therapy positively affected the OHRQoL. The mean OHIP-G-14 score decreased from 6.3 at baseline to 4.8 6–8 weeks after treatment (P < 0.001). The periodontal treatment had a highly positive effect on OHRQoL of patients with a PPD > 7 mm. Their mean OHIP-G-14 score showed a statistically significant decrease from 14.4 at baseline to 5.5 after treatment (P = 0.007). The presence of tobacco consumption, lower age and female gender were found to be associated with a higher OHIP-G-14 score and thus with a lower OHRQoL.
Figure 1.
Mean scores for 14-item German version of the Oral Health Impact Profile (OHIP-G-14) of subjects at baseline and 6–8 weeks post treatment, according to community periodontal index (CPI) score, gender, age and tobacco consumption. Significance (Student t-test): *P < 0.05, **P < 0.01, ***P < 0.001, n.s. = not significant.
The distribution of responses according to the items of the OHIP-G-14 at baseline and 6–8 weeks after treatment is shown in Table 3. Changes over the study period were observed for psychological discomfort ‘feeling of uncertainty’ and psychological disability ‘be upset’. These problems decreased by 12.2% and 8.4% from baseline to after treatment (response frequency ‘occasionally’, ‘often’ and ‘very often’ added). The biggest change over time was observed for the two added questions ‘gum bleeding’ and ‘unpleasant taste in mouth’. These discomforts reduced by 29.3% and 19.5% after periodontal therapy (response frequency ‘occasionally’, ‘often’ and ‘very often’ added). No change was analysed for the functional limitation ‘trouble pronouncing words’. Fewest problems at baseline and after treatment were observed for the handicap ‘unable to function’ and the social disability ‘unable to work’.
Table 3.
Distribution of German version of the 14-question Oral Health Impact Profile (OHIP-G-14) individual items response of periodontitis patients (n = 82) at baseline (at b) and 6–8 weeks after treatment (post t) (plus added questions ‘gum bleeding’ and ‘unpleasant taste in mouth’)
| Never | Hardly ever | Occasionally | Often | Very often | |
|---|---|---|---|---|---|
| At b./post t. (%) | At b./post t. (%) | At b./post t. (%) | At b./post t. (%) | At b./post t. (%) | |
| Functional limitation | |||||
| Trouble pronouncing words | 89/91.5 | 7.3/6.1 | 2.4/2.4 | 0/0 | 89/91.5 |
| Less flavour in food | 82.9/79.3 | 11/11 | 2.4/7.3 | 1.2/1.2 | 2.4/1.2 |
| Physical pain | |||||
| Uncomfortable to eat | 68.3/67.1 | 9.8/19.5 | 11/12.2 | 9.8/0 | 1.2/1.2 |
| Pain in oral area | 47.6/53.7 | 29.3/20.7 | 14.6/20.7 | 4.9/1.2 | 3.7/1.2 |
| Psychological discomfort | |||||
| Uncertainty | 58.5/69.5 | 15.9/17.1 | 11/7.3 | 7.3/3.7 | 6.1/1.2 |
| Tense feeling | 65.9/74.4 | 17.1/13.4 | 11/9.8 | 4.9/1.2 | 1.2/1.2 |
| Physical disability | |||||
| Difficult chewing | 85.4/87.8 | 4.9/11 | 7.3/1.2 | 2.4/0 | 0/0 |
| Interrupt meals | 86.6/90.2 | 7.3/6.1 | 2.4/3.7 | 3.7/0 | 0/0 |
| Psychological disability | |||||
| Upset | 63.4/78 | 15.9/9.8 | 14.6/7.3 | 4.9/2.4 | 1.2/1.2 |
| Being embarrassed | 75.6/84.1 | 11/8.5 | 8.5/6.1 | 2.4/1.2 | 1.2/0 |
| Social disability | |||||
| Trouble getting on with others | 75.6/82.9 | 14.6/8.5 | 6.1/3.7 | 1.2/1.2 | 1.2/0 |
| Unable to work | 84.1/90.2 | 8.5/6.1 | 3.7/2.4 | 2.4/1.2 | 0/0 |
| Handicap | |||||
| Life less satisfying | 58.5/84.1 | 25.6/7.3 | 6.1/6.1 | 3.7/2.4 | 3.7/0 |
| Unable to function | 92.7/96.3 | 4.9/2.4 | 2.4/1.2 | 0/0 | 0/0 |
| Added questions | |||||
| Gum bleeding | 25.6/53.7 | 34.1/35.4 | 31.7/9.8 | 8.5/1.2 | 0/0 |
| Unpleasant taste in mouth | 35.4/56.1 | 29.3/29.3 | 15.9/8.5 | 13.4/3.7 | 4.9/2.4 |
DISCUSSION
The present study attempted to analyse the impact of periodontal disease and non-surgical periodontal therapy on OHQoL. A total of 93 patients participated in the study, including 82 patients with periodontitis and a control group (n = 11). Two-thirds of the subjects reported that they regularly used the dental services.
Quality of life is an important factor, which brings the subjective feelings of patients into the heart of consideration. The OHQoL describes the patients’ subjective experience of oral health and provides information to complement objective clinical parameters such as PPD and PBI. The OHQoL was assessed using the German short-form version of the OHIP (OHIP-G-14)7, which has been shown to be reliable12 and sensitive to changes13.
Clinical outcomes of this study were comparable to previous reports using non-surgical periodontal therapy14. The mean PBI dropped from 0.56 at baseline to 0.20 after treatment (P < 0.001). There was a significant decrease in mean PPD of 1.03 mm from baseline to 6–8 weeks after treatment (P < 0.001). For patients with pockets 4–5 mm (CPI score 3) there was a mean difference in PPD of 0.7 mm between baseline and examination after treatment (P < 0.001). For patients with pockets 6 mm and greater (CPI-score 4) the mean difference was 1.2 mm (P < 0.001). The reduction in depth of pocket was related to the initial level of severity of the periodontal diseases. Morrison et al.14 reported a mean difference in pocket depth of 0.96 mm (P < 0.0001) between pretreatment and four weeks after treatment for pockets 4–6 mm. For pockets 7 mm or greater the mean difference was 2.22 mm (P < 0.0001).
This is in line with other studies using non-surgical periodontal therapy. Other studies have reported a reduction in PPD between 0.5 mm and 2.0 mm 48 months after treatment15., 16..
The impact of oral health on the quality of life of the patient group was appreciable, 25% (21/82) perceived an impact on their quality of life ‘often’ or ‘very often’ in one or more of the OHIP-G-14 items. Oral health status affected patients’ quality of life in regard to psychological discomfort (‘uncertainty’, ‘tense feeling’), psychological disability (‘upset’) and physical pain (‘pain in oral area’, ‘uncomfortable to eat’).
Oral health-related quality of life was significantly influenced by periodontal disease. Patients with a PPD > 7 mm had significantly higher mean OHIP-G-14 scores, which means that those patients had poorer OHRQoL. This highlights the influence of periodontal disease on quality of life and suggests that the OHRQoL measure is sensitive to periodontal health.
Periodontitis therapy positively affected the OHRQoL. The mean OHIP-G-14 score decreased from 6.3 at baseline to 4.8 6–8 weeks after treatment (P < 0.001). The periodontal treatment especially had a highly positive affect on the OHRQoL of patients with a PPD > 7 mm. Those patients showed a statistically significant reduction in their OHIP-G-14 score from 14.4 at baseline to 5.5 after treatment (P = 0.007). This demonstrates that periodontal therapy improves quality of life and suggests that this measure is sensitive to periodontal therapy.
These results of the present study are in accord with other studies that aimed to determine the impact of oral health on quality of life17 and which found that the patients with a greater number of deep periodontal pockets had poorer OHRQoL (Needleman et al. 2004)17. Ng & Leung10 showed an association between clinical periodontal status and OHRQoL and those patients with high/severe attachment loss scored significantly higher on the impact of oral health on their quality of life in the OHIP-14S.
The study demonstrates that age, gender and tobacco consumption are associated with the OHIP-G 14 score. It was found that women had a statistically higher OHIP-G 14 score than men. The impact of gender on quality of life has been demonstrated in a study by McGrath & Bedi18. This study showed that women perceived oral health as having a greater impact on their quality of life than men. In the present study patients with tobacco consumption had a higher OHIP-G 14 score than non-smokers. This is in line with a study of Fritschi et al.19 who reported a significantly lower health-related quality of life for smokers than for non-smokers. In comparison with the DMS IV, findings in the present study differ in that age was associated with older patients reporting a lower impact of OHRQoL.
Acknowledgements
We thank Dr W. Micheelis from the Institut der Deutschen Zahnärzte for fruitful discussions in the preparation of the study.
Conflict of interest
None declared.
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