2005
The Impact of a Clinical Pathway on Treatment Outcomes of Patients with Periodontitis in Public University Settings: A Quasi-Experimental Study
Tuti Ningseh Mohd-Dom1, Shahida Mohd-Said1*, Ooi Yow Hian1, Siti Lailatul Akmar Zainuddin2, Munirah Yaacob3, Haslinda Ramli4, Erni Noor5, Aznida Firzah Abdul Aziz6
Faculty of Dentistry, The National University of Malaysia, Kuala Lumpur, Malaysia1 School of Dental Sciences, University of Science Malaysia, Kubang Kerian, Malaysia2 Kulliyyah of Dentistry, International Islamic University of Malaysia, Kuantan, Malaysia3
Faculty of Dentistry, Islamic Science University of Malaysia, Kuala Lumpur, Malaysia4 Faculty of Dentistry, MARA University of Technology, Sungai Buloh, Malaysia5 Faculty of Medicine, The National University of Malaysia, Kuala Lumpur, Malaysia6
Corresponding author: 1*
Keywords: ABSTRACT
Care pathway, Periodontics, Dental scaling, Treatment outcome, Patient-reported outcome
This study tested a newly-developed clinical pathway (CP) to manage periodontitis patients against patients managed using usual care. This study was a multi-center quasi-experimental involving newly-diagnosed chronic periodontitis patients. Five dental schools at Malaysian public universities participated in the study. A total of 36 patients participated as a test group and received non-surgical periodontal treatment based on the CP and reviewed at 6, 12 and 24 weeks. Treatment outcomes at each review were compared with data of 36 patients who had been treated without CP and matched as historical controls. Outcome variables were clinical parameters namely probing pocket depth (PPD), clinical attachment level (CAL), gingival bleeding index and visible plaque index.
Improvements in these parameters for both groups were compared using independent t-test for normally distributed data and Mann–Whitney U test for non-normally distributed data. Both groups showed statistically significant post-treatment improvements for all clinical parameters. The CP group had significantly reduced number of sites for PPD ≥ 7mm and CAL gain compared to control group at 12th week (p=0.040) and 24th week (p=0.041), as well as between baseline to 24 weeks (p=0.039) with Cohen’s effect size 0.87, respectively. The use of a CP could lead to significant clinical improvement for patients with chronic periodontitis.
Its use could be recommended in dental settings involving multiple operators to ensure best outcomes based on standardized optimal care and shared guidelines for clinical decision-making.
This work is licensed under a Creative Commons Attribution Non-Commercial 4.0 International License.
1. INTRODUCTION
2006 Periodontitis is defined as inflammation of the gingiva and the adjacent attachment apparatus and characterized by loss of clinical attachment due to destruction of the periodontal ligament and loss of the adjacent supporting alveolar bone. A recent systematic review of epidemiologic data on severe periodontitis found it to be ranked as the sixth most prevalent condition out of 291 diseases and injuries affecting 10.8%
of world population [1], [2] and also an arising concern in the local scenario [3], [4]. The recent Global Burden of Study analysis cited severe periodontitis as having a high disability-adjusted life years (DALY) score when compared to other diseases and injuries [1]. While effective periodontal treatment is available [5], it has been shown to incur substantial burden on healthcare systems [6] thus defining periodontitis as a serious public health problem. Treatment of periodontitis requires professional removal of dental plaque and its various retentive elements and effective personal oral hygiene known as non-surgical periodontal therapy (NSPT). A major challenge despite the availability of authoritative guidelines and protocols for periodontal therapy [7- 9], the uptake of these guidelines is slow with many practitioners continuing to perform periodontal therapies based on their own habit, unscientific or outdated evidence [10].
One of the approaches to enhance quality of care is to reduce variations among practitioners and move practitioners to contemporary practice. In the general health system, care pathways or clinical pathways (CP) has been shown to reduce variation, and subsequently reduce the cost and time spent in hospitals and primary health clinics while maintaining the provision of high-quality services to patients [11- 13]. A CP is defined as an integrated plan of care for a homogenous group of patients with a particular diagnosis designed to avoid delays, optimally utilize available resources, and provide high quality of care that are based on the best clinical practice where multidisciplinary aspects are taken into account [14]. Realizing the benefits to patients and healthcare providers and its limited use in dentistry, our group had developed a CP to improve the non-surgical clinical management of patients with chronic periodontitis and the details of it are described elsewhere [15]. Established measures of periodontal therapy treatment outcomes are clinical parameters namely clinical attachment level (CAL), probing pocket depth (PPD), gingival bleeding index (GBI) and visible plaque index (VPI).
This present study aims to investigate the impact of introducing use of a clinical pathway on treatment outcomes of patients with chronic periodontitis managed by multiple operators in selected public universities.
2. MATERIALS AND METHODS
2.1 Study setting, participants and design
This study was conducted in five public universities between the period of 1st February 2016 to 28th February 2017. Patients who were adults aged 18 years and above, who have two or more interproximal sites (not on same tooth) with clinical attachment loss (CAL) of at least 4mm or with pocket depths (PD) of at least 5mm - all this affecting not less than 30% of tooth surface were included [16]. While patients who were pregnant or nursing or have received antibiotics or periodontal therapy in the previous three months were excluded from the study. New patients at each clinic who met the study inclusion criteria were invited to participate and receive treatment according to the CP.
For each patient, the following outcome variables were recorded: clinical attachment level (CAL), probing pocket depth (PPD), gingival bleeding index (GBI) and visible plaque index (VPI). These clinical parameters were recorded at baseline before treatment followed by 6 weeks, 12 weeks and 24 weeks post- initial instrumentation. Demographic data (age, gender, smoking status, and diabetic status) were also recorded at baseline. In addition, patient-based outcomes were also recorded using Oral Health Impact
2007 Profile 14-Malaysian (OHIP-14M) [17], Euroqol utilities (EQ-5D-3L) [18] and Euroqol Visual Analogue Scale (VAS) [18]. The study design flow is summarised in Figure 1 below.
Figure 1 Study flow-chart
To estimate the sample size required for this study, we used means and standard deviations of CAL measurements in a previous study [5]. The power analysis estimated that 36 patients, with α=0.05, yielded 90% power to detect significant CAL differences between groups. Clinical examiners in this study underwent a standardization and calibration session for CAL and PPD prior to the study - we used Nissin SRP upper and lower jaw models which had varying levels of CAL and PPD present on the teeth. The final measure of both parameters in intra-examiner and inter-examiner agreements were good to excellent (Kappa values ranging from 0.70 to 0.98).
2008 2.2 Statistical analysis
The Shapiro–Wilk test was used to determine normality of the outcome variables’ distributions. We measured within group differences for these variables at four time-points and differences in outcomes were analyzed using Friedman test. Differences of outcome variables between the two groups were analyzed using independent t-test for normally distributed data and Mann–Whitney U test for non- normally distributed data. A difference of p<0.05 was considered statistically significant. The data analysis was performed using SPSS V.23 (SPSS, IBM).
3. RESULTS
3.1 Patient characteristics: comparison between test and control group
Patients in this study had a mean age of 47.6 years (S.D 10.1 years) and almost equal proportions of males and females (Table 1). Majority (94.5%) had severe chronic periodontitis, about a quarter were smokers and one-fifth were confirmed to have diabetes mellitus. The characteristics of test and control groups were comparable at baseline.
Table 1 Comparison of patient characteristics between test and control group
Parameter All patients
(n=72)
Test n=36
Control n=36
p-value Age (SD) 47.6 (10.1) 46.1 (9.6) 48.9 (10.3) 1.190, t-test
Age range (years) 24-64 28-71
Female (%) 39 (54) 21 (58) 18 (50) 0.059, χ2
Severity of Disease (%):
Moderate 4 (5.6) 3 (8.3) 1 (2.8)
Severe 68 (94.5) 33 (91.7) 35 (97.2) 0.614, χ2
Smokers (%) 18 (25.0) 10 (27.8) 8 (22.2) 0.801, χ2
Diabetes (%) 17 (20.8) 8 (22.2) 7 (19.4) 0.772, χ2
3.2 Post-treatment clinical outcomes
Both test and control groups showed statistically significant improvements (p <0.001) in all clinical parameters except for the number of teeth where both groups had fewer teeth after periodontal therapy was carried out (Table 2). The test group had a significantly reduced number of sites with PPD ≥ 7mm than the control group recorded at 12th week (p=0.040) and 24th week (p=0.041) (Table 3). There was no other statistically significant difference (p > 0.05) between both groups recorded for all clinical parameters at other time points.
Table 2 Post-treatment clinical outcomes within groups Parameter Group Baseline
Median (IQR)
6 weeks Median (IQR)
12 weeks Median (IQR)
24 weeks Median (IQR)
p-value
No. of teeth Test 25.5(7) 25 (8) 24.5 (8) 24.5 (8) <0.001*
Control 27(9) 25 (10) 25 (9) 24 (10) <0.001*
GBI Test 70.5(42.9) 28.5 (36.4) 25.2(27.9) 26.1 (27) <0.001*
Control 66.3(36.7) 29.1(29.3) 22.8(19.6) 22 (15.6) <0.001*
VPI Test 64 (46.9) 38 (41.4) 35.5 (31.2) 26.5 (38.1) <0.001*
Control 55.4(38.5) 38 (47.2) 30 (25) 20 (26.1) <0.001*
PPD (mm) Test 3.6 (1.5) 2.9 (.9) 2.6 (.69) 2.4 (.67) <0.001*
2009 Control 3.7 (.1) 2.9 (.6) 2.8 (.83) 2.7 (.92) <0.001*
CAL (mm) Test 4.3 (2) 3.9 (1.6) 3.6 (1.6) 3.7 (1.6) <0.001*
Control 4.9 (1.7) 4.4 (1.6) 4.4 (1.7) 4.4 (1.8) <0.001*
*Statistically significant difference noted at different time point (Friedman test, p <0.05)
Table 3 Post-treatment clinical between test and control groups
Parameter Time point Test n=36 Control n=36 p-value No. of teeth
Median (IQR)
Baseline 25.5(7) 27(9) 0.655
6 weeks 25 (8) 25 (10) 0.664
12 weeks 24.5 (8) 25 (9) 0.619
24 weeks 24.5 (8) 24 (10) 0.972
GBI
Median (IQR)
Baseline 70.5(42.9) 66.3(36.7) 0.899
6 weeks 28.5 (36.4) 29.1(29.3) 0.958
12 weeks 25.2 (27.9) 22.8 (19.6) 0.728
24 weeks 26.1 (27) 22 (21.6) 0.835
VPI
Median (IQR)
Baseline 64 (46.9) 55.4(38.5) 0.730
6 weeks 38 (41.4) 38 (47.2) 0.986
12 weeks 35.5 (31.2) 30 (25) 0.144
24 weeks 26.5 (38.1) 20 (26.1) 0.276
No. of sites with:
PPD ≥7 mm Median (IQR)
Baseline 6 (16) 7 (9) 0.452
6 weeks 1.5 (5) 2 (6) 0.121
12 weeks 1 (4) * 2(4) * 0.040
24 weeks 0 (3) * 2 (6) * 0.041
PPD (mm) Baseline b 3.6 (1.5) 3.7 (.1) 0.677
6 weeks b 2.9 (.9) 2.9 (.6) 0.359
12 weeks a 2.7 (.6) 3 (.5) 0.172
24 weeks a 2.6 (.6) 2.9 (.4) 0.488
CAL (mm) Baseline a 4.5 (1.3) 4.6 (1.1) 0.938
6 weeks b 3.9 (1.6) 4.4 (1.6) 0.301
12 weeks b 3.6 (1.6) 4.4 (1.7) 0.241
24 weeks a 3.6 (1.1) 4.3 (.9) 0.100
a Mean (SD), b Median (IQR)
*Statistically significant differences noted in between both groups (Mann Whitney test, p <0.05)
3.3 PPD reduction and CAL gain (mm) between test and control group
Clinical outcomes specifically reduction of PPD and gain of attachment (CAL) for both groups throughout the study intervals show no statistically significant differences in PPD reductions between test and control group (Table 4). In contrast, there appears to be significantly higher gains of clinical attachment in the test group at 24 weeks post treatment (0.91 and 0.49 respectively, p=0.039) with effect size 0.87, as compared to gains achieved by the test group. According to [19], an effect size of d=0.8 suggests a large magnitude difference of treatment effect between test and control group.
Table 4 Pocket depth reduction and gain of clinical attachment level gain
2010 Parameter Duration from
baseline
Test n=36 Control n=36 p-value Effect Size PPD reduction
(mm)
Median (IQR)
6 weeks 0.6 (1.06) 0.59 (0.87) 0.573 -
12 weeks 0.86 (1.22) 0.77 (0.88) 0.285 -
24 weeks 0.9 (0.92) 0.85 (1.08) 0.738 -
CAL gain (mm) Mean (SD)
6 weeks 0.64 (0.63) 0.47 (0.61) 0.442 0.25
12 weeks 0.8 (0.73) 0.48 (0.67) 0.098 0.50
24 weeks 0.91 (0.7) * 0.49 (0.62)* 0.039 0.87
Statistically significant difference noted in between both groups (Independent t-test, p <0.05)
3.4 Patient-based outcomes for test groups over period of study
The multiple time point comparisons revealed that the improvements in overall OHIP-14 (reduction of impacts), VAS (increase) and utilities (increase) scores over the study period was significant (p < 0.001, Friedman test) (Table 5). We were not able to compare patient-based outcomes for the historical cohort as there was no baseline data.
Table 5 Patient-based outcomes (mean and standard deviation) for test group and comparison across different time points
Time point OHIP-14 Visual Analogue Scale
EQ-5D utilities score
Baseline 25 (18) 70 (34) 0.84 (0.19)
6 weeks 16 (17) 80.5 (20) 0.94 (0.12
12 weeks 11 (13) 85.5 (10) 0.94 (0.12)
24 weeks 10.5 (12) 90.0 (15) 0.94 (0.12)
P-value
(Friedman’s test) <0.001 <0.001 0.03
3.5 Use of clinical pathway variance analysis
Three variances had been recorded which took place at baseline. One was due to patient factor (who turned out late and the scheduled treatment could not be performed), and the other two was clinician factor and related to prescribing of 0.12% Chlorhexidine which was not stated in the clinical pathway.
4. DISCUSSION
In this study, patients responded favorably to NSPT regardless whether they had been managed with CP or usual care. Clinical improvements after non-surgical periodontal therapy (NSPT) are consistent with findings of major studies [20- 23]. For the Gingival Bleeding Index (GBI), patients in both groups started with the highest value at baseline followed by steady reduction with time. The control group had its lowest GBI at 24th week. Conversely, patients in the test group were noted to have a spike in GBI at 24th week for 0.9%. This could be contributed by two patients in the test group who were smokers at baseline and had successfully quit smoking during reassessment after 24 weeks of post treatment. It is well established that smokers had lower bleeding index due to the fewer gingival vessels [24]. In addition, the smoking cessation rate of the present study was higher than smoking cessation rates in other studies [25-], [26]. Smokers in this present study were referred to and had attended the “Quit Smoking” clinics, which are under the purview of the Ministry of Health, Malaysia. There were no statistically significant differences in visible plaque index between both groups at all time points despite efforts were given in the CP to standardize and reinforce oral hygiene instruction, and to make sure clinicians review as well as reinforce patients’ oral hygiene at every visit. This could indicate that reinforcement of oral hygiene had been a part of
2011 management protocol in the control group despite it not being recorded in the patients’ case notes. With regards to use of systemic antibiotics in the management of patients with periodontitis, its advantages had been indicated in few studies [27- 29]. Its use was advocated in the CP if clinicians deemed an adjunct periodontal therapy to be necessary. In the CP, the use of other adjuncts was not advocated, and clinicians could only prescribe systemic antibiotics if adjunct therapy was indicated. In contrast, the clinicians in the control group (usual care) had prescribed a wide array of therapy including locally delivered minocycline, diode laser or subgingival irrigation with 0.12% Chlorhexidine as an adjunct to initial root surface debridement.
The benefits of systemic over locally delivered antibiotics in terms of greater PPD reductions and CAL gains have been reported by several studies [28]. Moreover, a recent evidence-based clinical guideline from the United States did not advocate the use of locally delivered minocycline or diode laser as an adjunct to initial root surface debridement [8] - the use of minocycline microspheres was based on expert opinion as the evidence was lacking and the level of certainty was low. Use of diode laser was not recommended as its use as an adjunct to initial root debridement is not supported by current evidence [8]. With regards to the use of chlorhexidine for subgingival irrigation during initial root debridement, a German study showed no clinical benefits (PPD, CAL and bleeding on probing) in the use of 0.12% Chlorhexidine digluconate or 7.5% povidone–iodine [30].
Findings from this study suggest that the use of CP in non-surgical management of chronic periodontitis patients would lead to better treatment outcomes as measured by greater deep pocket reduction (initial PPD
≥7mm) at 3 and 6 months as well as CAL gain between baseline to 6 months post-treatment than patients managed with usual care. The usefulness of this CP however is by far limited to university settings whereby the multiple operators in this study were either periodontists or specialists in training. Patients in the CP and usual care were recruited from university settings, and this could have diluted the clinical significance of using clinical pathways as usual practice among the operators in these settings may not have much variation. It is not known if its use in different clinic settings shall yield similar outcomes or even larger differences between CP and usual care because clinical variations among operations may be greater.
Another consideration related to the usefulness of the CP is the follow-up period. This study had recalled patients up to 6 months-post treatments but tissue healing after NSPT could take place up to 9 months especially among patients with severe periodontitis. Given this need for additional follow-up period for complete healing, evaluation of the CP effectiveness at a later time-frame may yield larger improvements of clinical parameters hence supporting the use of CP for better quality care.
5. Conclusion
The use of CP among patients with chronic periodontitis had significantly reduced the number of sites with PPD ≥7mm at 3 and 6 months as well as significantly gained CAL between baseline to 6 months post treatment when compared to patients managed with usual care. Patients managed using the CP reported significant improvements in quality-of-life measures. Its use could be recommended in dental settings involving multiple operators to ensure best outcomes based on standardized optimal care and shared guidelines for clinical decision-making.
Acknowledgement
The authors gratefully acknowledge all clinical staff who participated in data collection and patient management at all study sites. This work was supported by the Ministry of Higher Education (Grant number: ERGS/1/2013/SKK11/UKM/02/2). This funding source had no role in the design and conduct of
2012 the study; collection, management, analysis, and interpretation of the data; and preparation, review or approval of the manuscript.
Conflict of Interest
The authors declare that there is no conflict of interests in the conduct of the study and in the preparation of this manuscript.
Ethical Policy and Institutional Review board statement
Permission to conduct the study was granted by the ethics committees of each of these universities prior to its commencement (main reference: UKM 1.5.3.5/244/DD/2015/007(2)). All the procedures have been performed as per the ethical guidelines laid down by Declaration of Helsinki 2013.
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