Baseline characteristics of the study participants
Of the 41 participants, sixty-nine percent were female and the average age was 49.2 years (range = 39.0 years, S.D =11.2 years). Over two thirds of the participants were either overweight or obese. Only one person reported cigarette smoking and he had been doing so for more than 10 years. Seventy-five percent of the participants had attended either primary or secondary education with only fourteen-point six percent reporting no school attendance. Ninety-seven-point seven percent had periodontitis and the mean HbA1c was 9.0 (SD=2.9). (See Table 1 in appendix i).
Table 1
A summary of Baseline characteristics of the study participants
Characteristics
|
Frequency (%)
|
BMI
|
|
<18.0 (Underweight)
|
1 (2.4)
|
18.5-24.9 (Normal)
|
10 (24.4)
|
25-29.9 (Overweight)
|
19 (46.4)
|
> 30(Obese)
|
11 (26.8)
|
Monthly income (Ugshs)
|
|
None
|
13 (31.7)
|
<400,000
|
18 (43.9)
|
400,000-1,000,000
|
8 (19.5)
|
>1,000,000
|
2 (4.9)
|
Daily frequency of brushing
|
|
None
|
2 (4.9)
|
Once
|
16 (39.0)
|
Twice
|
23 (56.1)
|
Method of teeth cleaning
|
|
None
|
2 (4.9)
|
Tooth brush
|
2 (4.9)
|
Tooth brush and tooth paste
|
37 (90.2)
|
Diabetic medication
|
|
Oral
|
27 (65.9)
|
Insulin
|
4 (9.8)
|
Both
|
10 (24.4)
|
Diabetic duration
|
|
< 1 year
|
4 (9.8)
|
2-5 years
|
13 (31.7)
|
6-10 years
|
11 (26.8)
|
>10 years
|
13 (31.7)
|
CAL
|
|
0 (0-3 mm)
|
20 (48.8)
|
1 (4-5 mm)
|
10 (24.4)
|
2 (6-8mm)
|
4 (9.8)
|
3 (9-11mm)
|
2 (4.9)
|
4 (12mm +)
|
5 (12.2)
|
Effect of periodontal treatment on periodontal status of study participants
Before treatment, forty participants had periodontitis and only one participant had normal periodontal status. Following periodontal treatment, the number of participants with periodontitis reduced drastically to 39.1%, the majority of these having only mild forms of the disease. The mean difference in number of teeth with bleeding sites was 6.49 (95% CI = 5.09- 7.88, t =9.39, p = 0.000) while that for the number of teeth with pockets 4.34 (95% CI = 3.03- 5.65, t =6.71, p = 0.000). There was a thus a statistically significant improvement in the periodontal status of the study participants following periodontal treatment (Table 2).
Table 2
Periodontal status of the study participants at baseline and after three months
|
Baseline
|
After 3 months
|
Periodontal status (CPI)
|
Frequency (percent)
|
Normal (0)
|
1 (2.4)
|
21 (58.5)
|
Calculus (2)
|
0 (0)
|
1 (2.4)
|
Mild periodontitis (3)
|
25 (61.0)
|
12 (29.3)
|
Severe periodontitis (4)
|
15 (36.6)
|
4 (9.8)
|
Total
|
41 (100)
|
41 (100)
|
Effect of periodontal treatment on selected periodonto-pathogenic bacteria
Following periodontal treatment, there was a reduction in proportion of participants with P. gingivalis from 48.7–31.7%, those with A. actinomycemcomitans from 36.6–24.4%, those with B.forsythus from 43.9–12.2% but no change in the proportion of those with F.nucleatum. There was thus a general reduction in the subgingival microbiota following periodontal treatment. (Table 3)
Table 3
Effect of periodontal treatment on selected periodonto-pathogenic bacteria
Bacteria
|
Frequency (%)
|
|
Baseline
|
After 3 months
|
Poryphromonas gingivalis
|
Present: 20 (48.7)
Absent: 21(51.3)
|
Present: 13 (31.7)
Absent: 28 (68.3)
|
Aggregatibacter actinomycetemcomitans
|
Present: 15 (36.6)
Absent: 26 (63.7)
|
Present: 10 (24.4)
Absent: 31 (75.6)
|
Bacteroides forsythus
|
Present: 18 (43.9)
Absent: 23 (56.1)
|
Present: 05 (12.2)
Absent: 36 (87.8)
|
Fusobacterium nucleatum
|
Present: 03 (7.3)
Absent: 38 (92.7)
|
Present: 03 (7.3)
Absent: 38 (92.7)
|
Effect of periodontal treatment on glycemic control
Generally, there was no difference in HBA1c levels following periodontal treatment (mean difference = 0.024, t = 0.06, p = 0.096). However, in 39% of the participants, there was a significant change in HbA1c levels following periodontal treatment (mean difference =1.85, t = 2.84, p = 0.007). Multilevel regression analysis, while controlling for individual, in these patients identified age younger than 47 years (t = -0.79, p = 0.440), duration of diabetes less than 1.7 years (t = -0.47, p = 0.640), BMI less than 27.7 (t = -1.83, p = 0.075) and HbA1c levels >8.9 (t = 2.03, p = 0.005) at base line to be associated with improved glycemic control. However, this association was only statistically significant for high HbA1c levels at base line.
Association between the different variables with HbA1c
Table 4 provides a summary of the final model multilevel regression modeling containing the set of variables that were retained in relation to their effect of the HbA1c levels controlling for the participant. What stands out in this final model was that the presence of Fusobacterium nucleatum (Fn) was associated with a significant 2.14 reduction in HbA1c levels keeping all other values in the model constant. Overall, the presence of Porphyromonasgingivalis (Pg) and Bacteroides forsythus (Bf) were each associated with an increase in the HbA1c levels. On the other hand, Aggregatibacter actinomycetemcomitans (Aa) was associated with a decrease in the levels of HbA1c. For these other bacteria it is important to note that these effects were not significant. It is also important to note that there was an interaction between the presence of Aggregatibacter actinomycetemcomitans (Aa) and having high random sugar associated with a -0.75 reduction in HbA1c levels (p value = 0.70). On average the intervention led to a 0.23-unit reduction in the levels of HbA1c compared to baseline for all participants. This was not significant. Respondents with a high random blood sugar levels had on average 3.00 units more than those with normal random blood sugar.
Table 4
A table showing the association between the different variables with HbA1c levels.
|
Value
|
Std.Error
|
DF
|
t-value
|
p-value
|
(Intercept)
|
6.14
|
1.27
|
37
|
4.82
|
0.00
|
FnYes
|
-2.14
|
0.94
|
36
|
-2.29
|
0.03
|
PgYes
|
0.24
|
0.49
|
36
|
0.50
|
0.62
|
BfYes
|
-0.86
|
0.59
|
36
|
-1.45
|
0.15
|
AaYes
|
1.07
|
1.86
|
36
|
0.57
|
0.57
|
rbs2High
|
3.00
|
1.32
|
37
|
2.28
|
0.03
|
Treatment.Yes
|
-0.23
|
0.32
|
36
|
-0.52
|
0.61
|
Sex M
|
0.69
|
0.68
|
37
|
1.01
|
0.32
|
AaYes: rbs2High
|
-0.75
|
1.94
|
36
|
-0.39
|
0.70
|