To assess the effectiveness of a chlorhexidine chip in the treatment of chronic periodontitis: A clinical and radiographic study.

CONTEXT: Controlled local delivery of disinfecting agents has been demonstrated to be efficient in improving the outcome of periodontal therapy. AIMS: The aim of the present study was to evaluate the efficacy of a controlled-release biodegradable chlorhexidine chip (Periocol CG) when used as an adjunct to scaling and root planing in the treatment of periodontitis. SETTINGS AND
DESIGN: The study was carried out as randomized controlled two-group parallel clinical trial.
MATERIALS AND METHODS: Forty patients in the age group of 30-65 years suffering from mild to moderate chronic periodontitis, having pocket depth ranging between 5 and 8 mm, were selected for the study. At the screening visit, complete history taking, periodontal examination and full-mouth supragingival scaling was carried out for each patient. At the baseline visit (on the 7(th) day), all clinical parameters and radiographic parameters were recorded at selected sites and patients were randomly assigned to either the control group (group A) or the treatment group (group B). All patients in both the groups received complete subgingival scaling and root planing. Then, in group B, chlorhexidine chip (Periocol CG) was inserted at the selected site. Patients were recalled at 1 month, 2 months and 3 months from the baseline for recording clinical observations, and radiographic parameters were recorded at the end of the study. STATISTICAL ANALYSIS: Mean, standard deviation, Chi-square test, "t" test for equality of means and paired samples correlations were used.
RESULTS: There was a statistically significant clinical attachment gain, reduction in bleeding index scores, probing pocket depth reduction and bone gain in both the groups, but group B showed better results than group A, and these differences were statistically significant.
CONCLUSIONS: The results of this study show that chlorhexidine chip (PerioCol-CG) is an effective adjunctive therapy to scaling and root planing in the treatment of chronic periodontitis.

RCT Entities:   Population Interventions Outcomes

INTRODUCTION

The periodontal diseases represent a group of localized microbial-induced infections involving the gingival and supporting tissues of the teeth. The process of periodontal pocket formation represents the pathological sequel of microbial- and inflammatory-mediated degradation of collagenous connective tissues and alveolar bone.[1]

Recent developments in science and technology have revolutionized the basic outlook and approach to the periodontal disease. A thorough understanding of the etiopathogenesis of periodontal disease has provided the clinicians and researchers with a number of diagnostic tools and techniques that has widened the treatment options.[2]

Conventional periodontal treatment consists of mechanical debridement to eliminate the subgingival microbiota and infected tissue in the inflamed pocket, usually performed by scaling and root planing.[3] The aim of nonsurgical periodontal therapy is to eliminate both living bacteria in the microbial biofilm and calcified biofilm microorganisms, i.e. dental calculus, from the root surface and from the subgingival area without surgical reflection of the soft tissues surrounding the teeth.[1]

However, deep periodontal pockets, especially with root surface concavities or furcation involvement, prevent the effectiveness of scaling and root planing. Consequently, this has led to the adjunctive use of antimicrobials, assuming that chemical aids would compensate for technical limitations and prevent early microbial recolonization to, ultimately, ensure the best chance for clinical improvements.[4] Goodson et al. first proposed the concept of controlled delivery of drug therapy in the treatment of periodontitis.[2] The advantage of this form of therapy is that it reaches the base of the periodontal pocket and is maintained for an adequate time for the antimicrobial effect to occur. Local administration of antimicrobial drugs directly into the periodontal pocket has been suggested as a means of bypassing systemic complications and targeting localized areas of periodontal destruction. The local concentration achieved can be much higher than is possible by the systemic route, and there is no dependence on patient compliance for success of the therapy.[5]

Different drugs used for local delivery are tetracyclines, including doxycycline[16] and minocycline,[7] metronidazole[89] and chlorhexidine.[10-14] Of all the chemical plaque control agents, chlorhexidine has proven to be the most effective, safe and clinically effective in reducing plaque and gingivitis and is the time-tested gold standard for the treatment of periodontal diseases. The aim of the present study was to evaluate the efficacy of a controlled-release biodegradable chlorhexidine chip (Periocol CG; Eucare Pharmaceuticals Pvt. Ltd., Chennai, India) when used as an adjunct to scaling and root planing in the management of periodontitis.

MATERIALS AND METHODS

Forty patients (28 males and 12 females) in the age group of 30–65 years suffering from mild to moderate adult periodontitis were selected among the patients visiting the dental OPD. The study protocol was approved by the institutional ethical committee. The patients were duly informed about the study and their signed consent was obtained.

Inclusion criteria

Patients with probing pocket depth ranging between 5 and 8 mm in one or both sides of the arches.

Patients with absence of any periapical/pulpal alteration on qualifying teeth.

Patients without any history of drug allergy to chlorhexidine.

Patients not using any medicated toothpaste/antibacterial mouthwash/antibiotics or any anti-inflammatory drug before the commencement of study for at least the past 3 months.

Exclusion criteria

Pregnant/nursing women.

Patients wearing any orthodontic appliance or other restorative appliance that can impinge on the tissues being assessed.

Patients on medication that may influence the pattern of tissue response.

Patients having soft or hard tissue tumors of the oral cavity.

Patients on any drug/alcohol abuse.

Material

A new preparation of sustained-release chlorhexidine (Periocol CG) containing approximately 2.5 mg chlorhexidine gluconate in a biodegradable matrix of type I collagen of fish origin was used in this study. The chip measures 4 mm in length, 5 mm in width and 0.25–0.35 mm in thickness (4 mm × 5 mm × 0.25–0.35 mm), and a single chip weighs about 10 mg. It is self-retentive and releases chlorhexidine in vitro, with a release profile of approximately 40–45% within the first 24 h and there on in a linear fashion for 7–8 days. Collagen-based membranes are resorbed after 30 days; however, their coronal edge degrades within the first 10 days. Its shelf life is 2 years [Figure 1].

Figure 1

Bullet shape of the sterile collagen periodontal chip with 2.5 mg chlorhexidine gluconate (PerioCol-CG)

Study plan

A flow chart indicating chronological order of procedures performed during the study period is shown in Figure 2. For each patient, the screening visit was scheduled 1 week before the baseline visit.

Figure 2

Flow chart indicating chronological order of procedures performed during the study period

At the screening visit (1 week before the baseline visit), after complete history taking and clinical examination, gingival index and probing pocket depth were recorded and full-mouth supragingival scaling was performed. At baseline, patients selected at the screening visit returned to the department and were enrolled in the study if they were willing to continue participation and met the enrolment criteria. Before starting any treatment, all clinical parameters (probing pocket depth, clinical attachment level,[1516] beeding index[17]) and radiographic parameters were recorded at selected sites for all the subjects.

Grouping

Patients were randomly assigned to one of two groups as follows:

Group A – Scaling and root planing alone (20 patients)

Group B – Scaling and root planing and application of a degradable drug delivery system containing 2.5 mg chlorhexidine (20 patients).

In group A, complete subgingival scaling and root planing was performed with hand instruments. In group B, after complete subgingival scaling and root planning, the experimental site was isolated and dried with compressed air for the placement of chlorhexidine chip as a wet chip becomes soft and more difficult to insert. Chlorhexidine chip was carried using dental forceps, with the round side of the chip facing away from the forceps. At the opening of the periodontal pocket, the round edge was kept along the long axis and the chip was inserted into the pocket until resistance was felt [Figure 3]. The patient was permitted to perform normal hygiene procedures, but instructed not to floss for 10 days in the selected sites and adjacent sites at the same interproximal regions to avoid the possibility of chlorhexidine chip dislodgement from the crevice. Patients were also instructed not to use any chemotherapeutic mouthrinse or oral irrigation devices.

Figure 3

Method of placement of chlorhexidine chip (PerioCol-CG) within the periodontal pocket

Patients were recalled for follow-up at 1, 2 and 3 months from the baseline for recording clinical observations, and radiographic parameters were recorded at the end of the study only.

RESULTS

Forty patients were enrolled in the study but 38 patients (26 males and 12 females) completed the study. Data from two patients who failed to attend an examination during two consecutive time frames were excluded from the study. The mean age of the patients was 38.6 years (range, 30–54 years) and there were 28 males (70.0%) and 12 females (30.0%). The male:female ratio was 16:4 (M=80.0%, F=20.0%) and 12:8 (M=60.0%, F=40.0%) in group A and group B, respectively. No statistically significant difference was found between the two groups on the basis of cross-tabulation of sex groups by using the Chi-square test at baseline.

Probing pocket depth

In group A, the mean probing pocket depth of 20 participants at baseline was 5.36±0.59 mm, and it decreased to 5.26±0.65 mm, 5.21±0.71 mm and 4.94±0.97 mm at 1-, 2- and 3-month intervals, respectively [Table 1]. The difference between the mean score when put to statistical analysis was found to be statistically significant only between observations made at baseline and at 3-month intervals.

Table 1

Mean values of all the clinical parameters taken during the study in both the control group (group A) and the experimental (group B)

In group B, the mean probing pocket depth of 20 participants at baseline was 6.94±0.84 mm, and it decreased to 6.47±0.84 mm, 5.89±1.41 mm and 5.68±1.60 mm at 1-, 2- and 3-month intervals, respectively [Table 1]. The difference between the mean score when put to statistical analysis was found to be statistically highly significant for the observations made between baseline and 1-month intervals and between baseline and 3-month intervals [Table 2,Figure 4].

Table 2

Comparison of pocket depth changes for both control group (group A) and experimental group (group B) at each recall visit

Figure 4

Line diagram showing comparison of changes in pocket depth and clinical attachment level in both control group (group A) and experimental group (group B)

Paired samples correlation

In group A, a statistically highly significant correlation was found between baseline and 1-month interval and statistically significant correlations were also observed between baseline and 2-month intervals and between baseline and 3-month intervals.

In group B, a statistically highly significant correlation appeared between baseline and 1-month interval, between baseline and 2-month intervals and between baseline and 3-month intervals when the mean observations for pocket depth reduction were compared [Table 3].

Table 3

Paired samples correlations of probing pocket depth in both control group (group A) and experimental group (group B)

Clinical attachment level

In group A, the mean clinical attachment level of 20 patients at baseline was 7.36±1.06 mm. The mean clinical attachment level at 1-, 2- and 3-month intervals was 7.21±1.18 mm, 7.36±1.11 mm and 6.89±1.04 mm, respectively [Table 1]. The difference between the mean scores when put to statistical analysis was found to be statistically insignificant between baseline and 1-month interval, baseline and 2-month intervals and baseline and 3-month intervals.

In group B, the mean clinical attachment level of 20 patients at baseline was 9.52±0.90 mm. The mean clinical attachment level at 1-, 2- and 3-month intervals was 9.15±1.01 mm, 8.47±1.34 mm and 8.86±1.53 mm, respectively [Table 1]. The difference between mean scores when put to statistical analysis was found to be statistically significant at 1-month interval and highly significant at 2- and 3-month intervals when compared with observations made at baseline [Table 4,Figure 4].

Table 4

Comparison of change in clinical attachment level for both control group (group A) and experimental group (group B)

In group A, a statistically highly significant correlation was found in clinical attachment level at 1 month compared with baseline readings and at 2 months compared with baseline but a nonsignificant relation was found in clinical attachment level at 3 months compared with the baseline readings.

In group B, a statistically highly significant correlation was found in clinical attachment level at 1 month compared with baseline readings and a statistically significant correlation was found in clinical attachment level at 2 months compared with baseline (P= 0.013) and at 3 months compared with baseline readings [Table 5].

Table 5

Paired samples correlations of clinical attachment level in both control group (group A) and experimental group (group B)

Bleeding index scores

In group A, the mean bleeding index score of 20 patients was 1.15±0.33, 0.94±0.55, 1.0±0.44 and 0.89±0.39 at 0, 1, 2 and 3 months intervals, respectively [Table 1]. The difference between the mean scores when put to statistical analysis was found to be statistically significant only at 3-month intervals.

In group B, the mean bleeding index score of 20 patients was 1.28±0.41, 1.05±0.52, 0.87±0.40 and 0.89±0.48 at 0, 1, 2 and 3 months intervals, respectively [Table 1]. The difference between the mean scores when put to statistical analysis was found to be statistically insignificant only at the 1-month interval and highly significant at the 2- and 3-month intervals when compared with baseline readings [Table 6,Figure 5].

Table 6

Comparison of bleeding index score in both control group (group A) and experimental group (group B)

Figure 5

Line diagram showing comparison of bleeding index (Muhlemann and Sons) in both control group (group A) and experimental group (group B)

At all periods of observation, a statistically nonsignificant correlation was observed in the bleeding index score in group A as well as in group B when compared with the baseline readings [Table 7].

Table 7

Paired samples correlations of bleeding index in both control group (group A) and experimental group (groupB)

Radiographic findings

At 3-month intervals, 21% of the sites in patients of group A showed bone gain ranging from 1 to 2 mm, 5% sites showed bone loss and 74% of the sites maintained the bone level as compared with baseline observations. In patients of group B, 47% of the sites showed bone gain ranging from 1 to 2 mm, none of the sites showed bone loss and 53% of the sites maintained the bone level. The difference between these scores when put to statistical analysis was found to be statistically highly significant [Table 8,Figure 6].

Table 8

Comparison of percentage of sites exhibiting changes in alveolar bone height in both control group (group A) and experimental group (group B)

Figure 6

Bar diagram showing radiographic changes from baseline to 3 months interval in alveolar bone height in both control group (group A) and experimental group (group B)

Adverse effects

Adverse effects were noted in only five subjects of group B and none of the subjects of group A showed any adverse effects due to treatment procedure. The difference between these scores when put to statistical analysis was found to be statistically significant [Table 9,Figure 7].

Table 9

Comparison of any adverse effects of treatment in both control group (group A) and experimental group (group B)

Figure 7

Bar diagram showing any adverse effects of treatment outcomes in both control group (group A) and experimental group (group B)

DISCUSSION

The present study was undertaken to evaluate the efficacy of subgingivally placed controlled-release degradable chlorhexidine chip (Periocol CG) as an adjunct to scaling and root planing in the management of chronic periodontitis. Three months had been selected as the time duration of the study because effects of locally delivered controlled-release chlorhexidine have been shown to be evident up to 11 weeks after administration,[1819] and 3 months correspond to the typical recall interval for periodontal patients.[4]

Mean reduction in pocket depth from baseline for the duration of the study at 1 month, 2 months and 3 months were 0.10+0.45 mm, 0.15+0.60 mm and 0.42+0.76 mm, respectively, for group A (scaling and root planing alone group) and 0.47+0.61 mm, 1.05+0.91 mm and 1.26+1.19 mm, respectively, for group B (scaling and root planing plus chlorhexidine chip group) [Table 2]. Our results are in accordance with those of Srinivas et al.[20] and Rodrigues et al.,[21] who found a statistically significant difference in mean pocket depth reduction between the scaling and root planing group and the combination group. According to Soskolne et al.,[22] if, after definitive periodontal therapy, there are still residual pockets of ≥5 mm remaining, then combined routine periodontal maintenance therapy along with the chlorhexidine chip is advisable.

Clinical attachment gain from the baseline for the duration of study at 1 month, 2 months and 3 months intervals were 0.15±0.37 mm, 0.00±0.57 mm and 0.47±1.26 mm, respectively, for group A and 0.36±0.76 mm, 1.05±1.12 mm and 1.15±1.30 mm, respectively, for group B [Table 4]. The findings of our study are in partial accordance with those of Azmak et al.,[3] who observed a significant improvement in the clinical attachment level in both the scaling and root planing plus chlorhexidine chip group and the scaling and root planing alone group at 1 month, 3 months and at 6 months as compared with baseline.

At the end of the study, the mean change in clinical attachment level from baseline was 0.47±1.26 mm for group A and 1.15±1.30 mm for group B [Table 4]. These findings are in accordance with those of Jeffcoat et al.,[23] who observed improved attachment levels over the 9-month period for the scaling and root planing plus chlorhexidine chip group and a significant improvement compared with the scaling and root planing alone group at 9 months.

Reduction in the bleeding index score at 1 month, 2 months and 3 months intervals was 0.21±0.65, 0.15±0.55 and 0.26±0.45, respectively, for group A and 0.23±0.69, 0.42±0.44 and 0.39±0.56, respectively, for group B as compared with baseline [Table 6]. There was a statistically significant difference in the bleeding index score observed at 3 months interval in group A and statistically highly significant difference in bleeding index score at 2 months and at 3 months intervals in group B compared with baseline. These findings are in accordance with those of Azmak et al.,[3] who found a mean reduction in bleeding index score at 1 month and 3 months for both the combination group and the scaling and root planing alone group when compared with baseline. However, at all periods of observations, a statistically nonsignificant correlation was observed in the bleeding index score in between groups A and B. With respect to radiographic findings, 21% of the sites in group A and 47% of the sites in group B experienced bone gain at the end of the study, whereas 74% and 53% of the sites in group A and group B, respectively, maintained bone level that was statistically highly significant (P=0.001). The results of our study are in accordance with those of Jeffcoat et al.,[23] who observed with digital substraction radiography technique that 15% of the sites in the scaling and root planing alone group and 11% of the sites in the scaling and root planing plus placebo chip group experienced bone loss during the study; in contrast, no sites in the scaling and root planing plus chlorhexidine chip group exhibited bone loss. The differences in the results observed may be attributed to the use of intraoral periapical radiograph along with X-ray mesh in our study for assessing changes in alveolar bone height, which is a comparatively less-sensitive technique for the detection of small osseous changes.

About five patients (26%) observed adverse effects like gingival pain and tender gums in group B, whereas there was not even a single patient in group A who reported any side-effect due to the treatment procedure. Adverse effects occurring in the first week of the study appeared to be associated with chip placement at baseline after scaling and root planing. None of the changes discovered on oral examination were of a serious and irreversible nature.[24]

CONCLUSION

In conclusion, the results of this study show that chlorhexidine chip containing 2.5 mg chlorhexidine gluconate (Periocol CG) is an effective adjunctive therapy to scaling and root planing in the treatment of chronic periodontitis. It provides a safe, easily applied single-dose means of achieving significantly better clinical results than scaling and root planing alone. The adjunctive use of the chlorhexidine chip with scaling and root planing resulted in a clinically meaningful improvement in pocket depth reduction and clinical attachment level gain compared with scaling and root planing alone.