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Table of Contents   
ORIGINAL RESEARCH  
Year : 2014  |  Volume : 25  |  Issue : 3  |  Page : 316-320
Osteoporosis and periodontitis: Is there a possible link?


Department of Periodontics and Oral Implantology, A.M.E's Dental College, Hospital and Research Centre, Raichur, Karnataka, India

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Date of Submission15-Feb-2013
Date of Decision03-Sep-2014
Date of Acceptance10-Jun-2014
Date of Web Publication7-Aug-2014
 

   Abstract 

Background: Periodontitis and osteoporosis are two diseases found worldwide having the main characteristic of increasing intensity with age. Periodontitis is associated with resorption of the alveolar bone. Osteoporosis is characterized by bone loss leading to structural bone transformation. The association between periodontitis and osteoporosis is continually being examined. The aim of this study is to examine the condition of periodontal tissues in patients suffering from osteoporosis and establish a possible link.
Materials and Methods: Cross-sectional study with 200 samples having test (n = 100) and control group (n = 100) were checked for periodontal condition. A total of 100 patients diagnosed as having osteoporosis based on bone mineral density at distal end of radius were regarded as test group and 100 subjects included in control group were healthy. Periodontal parameters measured were plaque index (PI), gingival index (GI), probing depth (PD), and clinical attachment loss (CAL). Statistical test performed were Student's paired t-test and unpaired t-test and Pearson's correlation coefficient.
Results: Probing depth and CAL were significantly negatively co-related with T-score in test group when compared with control group. This meant an inverse relationship in between the T-score and the clinical parameters, PD and CAL. Furthermore, some difference was noted in test group in PI, GI and PD, CAL and T-score when compared with the controls.
Conclusion: Thus, we conclude that there is a definite relationship between osteoporosis and periodontitis based on PD and CAL.

Keywords: Clinical attachment loss, osteoporosis, T-value

How to cite this article:
Aspalli SS, Shetty V S, Parab PG, Nagappa G, Devnoorkar A, Devarathnamma M V. Osteoporosis and periodontitis: Is there a possible link?. Indian J Dent Res 2014;25:316-20

How to cite this URL:
Aspalli SS, Shetty V S, Parab PG, Nagappa G, Devnoorkar A, Devarathnamma M V. Osteoporosis and periodontitis: Is there a possible link?. Indian J Dent Res [serial online] 2014 [cited 2020 Sep 26];25:316-20. Available from: http://www.ijdr.in/text.asp?2014/25/3/316/138327
Osteopenia together with osteoporosis is bone reduction resulting from imbalance between resorption and bone formation, with resorption tending to increase. [1] According to the World Health Organization, osteoporosis is considered to be present when bone mineral density (BMD) is 2.5 standard deviations below the young normal. Osteoporosis before fractures is termed a "silent disease". [2]

Periodontitis, an inflammatory disease characterized by resorption of the alveolar bone as well aloss of soft tissue attachment to the tooth, is a major cause of tooth loss in adults. [3] Like osteoporosis, it is a silent disease, not causing symptoms until late in the disease process. Both periodontitis and osteoporosis are bone-resorptive diseases. [2]

The aim of this study was to examine the condition of periodontal tissues in people who were diagnosed with osteoporosis and to compare the results with periodontal tissues in people not suffering from osteoporosis.


   Materials and methods Top


This cross-sectional study included 200 subjects who were selected randomly, out of which 100 were in the test group consisting of patients diagnosed with osteoporosis on the basis of T-score. The control group comprised of

100 people diagnosed as not having osteoporosis or osteopenia. Subjects were recruited from September 2010 to November 2011 in A.M.E's Dental College and Hospital, Raichur, Karnataka. Both males and females were included in this study, aged between 35 and 65 years. All the patients were checked for the prevalence of periodontitis based on certain clinical parameters. The osteoporotic patients underwent a regular medical treatment in a private clinic for osteoporosis hereafter. Controls were of similar age structure as the test group.

The clinical parameters used for determining the condition of periodontal tissues included: Plaque index (PI), [4] gingival index (GI), [5] probing depth (PD) and clinical attachment loss (CAL). All clinical parameters were checked by the same examiner PP to avoid interexaminer bias. Exclusion criteria considered was: (i) Patients with any systemic diseases (ii) patients who received periodontal treatment in last 6 months (iii) patients on any medications affecting calcium metabolism (iv) pregnant women and lactating mothers and (v) smokers.

Conventional radiography was not used due to its shortcomings. Shortening or elongation of X-rays, physiological variations in contrast and density, as well as superimpositions of anatomic structures, makes this method useless in determining destruction and treatment of the alveolar bone. Diagnosis of osteoporosis was done based on the T-score as determined by bone densitometer at the distal end of the radius by an orthopedic surgeon in

his private clinic. Materials used to examine periodontal status in the study were disposable mouth mirrors and William's graduated periodontal probe along with disposable gloves, mouthmasks, and kidney trays.

The study has been approved by the Ethical Committee in A.M.E'S College, Hospital and Research Center, Raichur. Oral and written informed consent was obtained from all the participants in the study.

Statistical analysis

Paired t-test and unpaired t-test were used to study the relation in between the clinical parameters in test group and control groups and for intergroup comparison. Furthermore, Pearson's correlation coefficient was used to find an association between the T-score and the clinical parameters.


   Results Top


The demographic data of the subjects included in this study are summarized in [Table 1]. The groups under examination consisted of the same number of patients of similar age approximately. The patients had an average age of 44.6 ± 5.4 years in the test group and 46.3 ± 6.9 years in the control group. [Table 2] gives standard periodontal measurements. Test group, as expected, had higher baseline PI, GI, PD and CAL than the control group subjects. Comparison of clinical parameters and T-score between test and the control group showed a P value that were highly significant for the parameters such as PI, GI, CAL and T-score. PD showed slightly significant P value in comparison with the control group participants. Mean difference in the T-score calculated as -3.13 and CAL as 2.09 mm. P value was considered as significant when P < 0.05.

Relationship between osteoporosis (T-scores) and clinical parameters in cases and controls were analyzed by Pearson's correlation coefficient [Table 3]. Only the relationship between T-score with PD and CAL was significant in the test group. For this reason the r-value is calculated and it can be positive or negative depending upon the situation. Here, it can be noted that the r-value is negative indicating that there is an inverse relationship between the T-score and the two clinical parameters, that is, PD and CAL. P < 0.01 is considered to be significant here.

[Figure 1] shows the T-score in two groups that represents the BMD value, showing a mean value of -3.08 in the test group and 0.05 mean in the control group. Furthermore, [Figure 2] and [Figure 3] indicate that an inverse relationship exist between the T-score and the clinical parameters, PD and CAL. Thus, it can be considered that as the BMD decreases, the PD and CAL increases.
Figure 1: Comparison of T-score in test and control group

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Figure 2: Relationship between probing depth and T-score

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Figure 3: Relationship between clinical attachment loss and T-score

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Table 1: Demographic data of the subjects


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Table 2: Comparison of clinical parameters and T-scores between osteoporosis and control subjects


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Table 3: Relationship between osteoporosis (T-score) and clinical parameters in test and control groups


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   Discussion Top


Periodontitis includes infection and a form of illness associated with specific pathogenic bacteria existing in the subgingival area. The onset and progression of periodontal infection can be significantly modified by local and systemic conditions, known as "risk factors". Local factors are various and directly related to periodontal tissues. They accelerate the invasion of bacteria and development of dental plaque. Systemic risk factors have been considered in recent epidemiological studies. [2],[6],[7] Risk factors include diabetes mellitus [8] and smoking. [9] These two risk

factors are related to the, onset and progression of periodontitis and they are extremely important when periodontitis prevention and therapy are to be considered. Recent studies have documented the existence of some other potentially important periodontal risk factors such as stress, sex, age, genetic factors and also osteopenia (osteoporosis as a consequence of estrogen deficit). [10],[11] Definition of osteoporosis has now evolved beyond low BMD to recognize impaired bone qualities related to bone size, bone morphology, material properties of bone, and matrix and bone remodeling are responsible for bone density insufficiency fractures. Most common insufficiency fractures are fractures of spine, hip and wrist. [12] Discussions about the association between these two bone-damaging diseases started in 1960. [13] According to some studies, osteoporosis may be a very important factor of tooth loss. Kribbs compared patients with osteoporosis and without it and found out that the osteoporotic group comprised more subjects with no teeth or with a greater number of lost teeth. [14] Positive association was found in between osteoporosis and periodontal disease in a review despite of the incipient evidence linking the two diseases. [15]

Brennan et al. stated that there is association between BMD at different skeletal sites and CAL; however, the most consistent and strongest associations with CAL were found with total forearm and whole body BMD had worst site T-score. [16] Therefore, in the present study distal radius BMD was measured for determining the T-score value. Ronderos et al. in a NHANES III study, found that women with high calculus index and low BMD had significantly more CAL than women with a similar calculus index and normal BMD. [17] Shen et al. showed increased attachment loss in osteoporotic sites in postmenopausal women suggesting that osteoporosis may act as a risk factor for periodontitis. [18] von Wowern et al. concluded, severe osteoporosis reduces the bone mineral content that may be associated with less favorable attachment level in case of periodontal disease. [19] Similar findings were shown in a cross-sectional investigation of the association between systemic BMD and periodontal status. In this study, 30 postmenopausal, Asian-American women were screened for osteoporosis and chronic periodontitis. Periodontal assessments included tooth loss, PI, PDs, and clinical attachment levels. Statistically significant negative correlations were found between BMD and tooth loss and also BMD and CAL, independent of plaque scores. [20] Similarly, in this study, comparison between mean PI, GI and CAL in cases and controls gave highly statistical significant difference in test and control group. Correlation analysis between T-scores, PI, and GI gave a negative correlation, although this wasn't statistically significant. A negative correlation was found in T-score and CAL and also PD in the test group that was statistically significant. Interpretation of the results suggests that as the BMD decreases the CAL and PD increases. A longitudinal study conducted in community dwelling older adults suggested a positive relation between CAL and BMD. [21] Recent studies provide stronger evidence of an association between osteoporosis and CAL in humans. [22],[23],[24] In contrast, cross-sectional study demonstrated that periodontal attachment loss was correlated with tooth loss, but not with vertebral or proximal femur bone density. [25] Elders et al. concluded that systemic bone mass was not an important factor in the pathogenesis of periodontitis. [26] In controlling for some potential confounding factors of age, smoking and number of remaining natural teeth, Weyant et al. were still not able to provide statistically significant association between the parameters of periodontal disease and measures of systemic BMD. [27]

A review of 17 articles on relationship between osteoporosis and periodontal disease shows that 11 articles showed a positive relation between osteoporosis and periodontal disease and 6 articles showed no significant relation between the two. [13] Another review article on osteoporosis and periodontal disease updated that epidemiological and clinical data provide limited but convincing evidence to suggest an association between the two bone-destructive diseases. The review also added that this relation could probably be due to the common risk factors associated with both the diseases. [28]

Besides the presence of common risk factors, a possible interplay between osteoporosis and periodontal disease is also suggested at a pathogenetic level. In fact, a bi-directional interference between the two diseases has been proposed: In particular, the reduced BMD, characterizing OP and the related alteration of trabecular pattern may lead to a more rapid jawbones resorption caused by PD, resulting in the invasion of periodontal bacteria. Invading bacteria, in turn, may alter the normal homeostasis of bone tissue, increasing osteoclastic activity and reducing local and systemic bone density by both direct effects (release of toxins) and/or indirect mechanisms (release of inflammatory mediators). [29] A significant connection between periodontitis and osteoporosis can be confirmed by the action of pro-inflammatory cytokines and prostaglandins. Since these mediators develop in both periodontitis and osteoporosis, there is a possibility of double connection between these two diseases. [30],[31] Further studies relating osteoporosis and periodontitis to heredity, poor oral hygiene, tobacco usage in any form should be undertaken to establish a better relationship between the two diseases.


   Conclusion Top


Periodontitis, as a chronic inflammatory disease, which influences the appearance of pro-inflammatory cytokines through its pathogen bacteria, could be at the same time the source of osteoporosis. This hypothesis is becoming more and more relevant and should be proved in the future. In addition, a close cooperation between doctors-rheumatologists and periodontists-is necessary for this reason. By treating periodontitis, mediators of inflammation and bone resorption are decreased and development of osteoporosis may be thus retarded and vice versa. This study shows that PD and CAL are inversely correlated to T-score that measures the BMD. Thus osteoporosis can be considered as a risk factor for periodontitis. Clinical consequence of these findings suggests that osteoporotic patients should be advised to give more attention toward their oral health to prevent periodontal problems. Further longitudinal studies with larger sample size are required for better understanding of the relationship between these two diseases.

 
   References Top

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26.Elders PJ, Habets LL, Netelenbos JC, van der Linden LW, van der Stelt PF. The relation between periodontitis and systemic bone mass in women between 46 and 55 years of age. J Clin Periodontol 1992;19:492-6.  Back to cited text no. 26
    
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Correspondence Address:
Shivanand S Aspalli
Department of Periodontics and Oral Implantology, A.M.E's Dental College, Hospital and Research Centre, Raichur, Karnataka
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/0970-9290.138327

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    Tables

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