Male Infertility and Dental Health Status: A Systematic Review

Is there an association between periodontal disease and infertility? A systematic review

BACKGROUND

Today, idiopathic infertility is becoming more frequent, affecting more than 186 million people in the world. The presence of comorbidities makes patient management complex, requiring individualized infertility treatment. Periodontal diseases could contribute negatively to the management of infertility, increasing inflammation, oxidative stress and insulin resistance, and contributing negatively to the development and progression of comorbidities associated with these two entities. The aim of this systematic review is to explore whether there is an association between periodontal diseases and male and female infertility and deepen into the possible mechanisms underlying this association.

MATERIAL AND METHODS

The studies analyzed in this research included a total of 4871 patients (732 men and 4139 women), were original studies with high quality, mostly with a control group. Authors who have investigated idiopathic infertility suggest that infertility is associated with diseases that present low-grade chronic inflammation, oxidative stress and insulin resistance (such as obesity, type 2 diabetes and polycystic ovary syndrome), which are in turn related to periodontal diseases.

RESULTS

A higher prevalence of periodontal disease was found in patients with infertility compared with controls. Periodontal diseases could initially be mediated by a local and systemic proinflammatory environment, which favors a pro-oxidant state, leading to oxidative stress and, finally, irreversible destruction of the periodontal tissue. Insulin resistance, oxidative stress and inflammation are present in the pathologies associated with an increase in the prevalence and severity of periodontal diseases (such as obesity, type 2 diabetes and polycystic ovary syndrome). Therefore, IR, low-grade chronic inflammation and the oxidative stress could be the pathophysiological mechanisms linking idiopathic infertility and periodontal diseases.

CONCLUSIONS

Studies suggest an association between infertility and periodontitis. Future researches are necessary to find causality factors. Studying the patient in a global and multidisciplinary way could help in the management and treatment of idiopathic infertility.

The association between oral inflammatory load and semen and sperm functional analysis: A cross-sectional study

Background

Studies have suggested a correlation between periodontitis and reduced male fertility. Inflammation has been described as the link between these ailments. Oral inflammatory load (OIL) can be measured through oral polymorphonuclear neutrophil (oPMN) count, which is associated with periodontal diseases. This cross-sectional study assessed the possible correlation between OIL and the functional parameters of sperm cells.

Methods

In 229 volunteers, oral rinse and semen samples were assessed for oPMN, semen polymorphonuclears (sPMNs), sperm concentration, total sperm count, motility, morphology, and sperm DNA fragmentation index (SDFi). A multiple linear regression model was conducted to evaluate the relationships between oPMN and semen parameters.

Results

The effect of elevated oPMN counts on total motility rate, progressive rate, and percentage of sperm cells with normal morphology was significant (P<0.001), with an inverse relationship, i.e., with every unit increase in oPMN count, the mentioned parameters would decline by 0.573, 0.367, and 0.407 units, respectively. oPMN counts also correlated positively with sPMN counts and SDFi (P<0.001), i.e., with every unit increase in the oPMN measures, sPMN counts would increase by 0.126 million/mL, with an 0.733% increase in SDFi. However, there was no significant association between oPMN counts and sperm concentration.

Conclusion

OIL, as represented by oPMN counts, might affect male fertility as there is a positive correlation between the levels of these inflammatory cells and decreased sperm motility, abnormal morphological changes, increased sPMN counts, and increased SDFi.

Can periodontal disease affect conception? A literature review

Today periodontal health is considered as an integral part of systemic health itself and no longer as a single factor. The literature recognizes that the presence of periodontal disease can represent a risk factor for numerous systemic conditions such as heart disease and diabetes. In recent years, we have witnessed a progressive interest regarding the influence exerted by this condition on reproduction, as well as the possible repercussions on conception possibilities. Upon analyzing a limited number of studies available for the correlation between periodontal disease and female infertility, it could be inferred that this condition can be equated to the presence of a real outbreak of infection and therefore exert its influence, not only through bacterial translocation in the bloodstream, causing the systemic dissemination of pathogens, but also through the production of cytokines and immunoglobulins by inflammatory mediators. This situation limits bacterial growth, but it could cause damage to the fetus, to the reproductive system, and could hinder conception attempts. Although further research is needed to better clarify the mechanism underlying the possible correlation between periodontal disease and female infertility, the present article aims to review all the available literature on this topic.

Characterization of Human Genes Modulated by Porphyromonas gingivalis Highlights the Ribosome, Hypothalamus, and Cholinergic Neurons

Porphyromonas gingivalis, a bacterium associated with periodontal disease, is a suspected cause of Alzheimer's disease. This bacterium is reliant on gingipain proteases, which cleave host proteins after arginine and lysine residues. To characterize gingipain susceptibility, we performed enrichment analyses of arginine and lysine proportion proteome-wide. Genes differentially expressed in brain samples with detected P. gingivalis reads were also examined. Genes from these analyses were tested for functional enrichment and specific neuroanatomical expression patterns. Proteins in the SRP-dependent cotranslational protein targeting to membrane pathway were enriched for these residues and previously associated with periodontal and Alzheimer's disease. These ribosomal genes are up-regulated in prefrontal cortex samples with detected P. gingivalis sequences. Other differentially expressed genes have been previously associated with dementia (ITM2B, MAPT, ZNF267, and DHX37). For an anatomical perspective, we characterized the expression of the P. gingivalis associated genes in the mouse and human brain. This analysis highlighted the hypothalamus, cholinergic neurons, and the basal forebrain. Our results suggest markers of neural P. gingivalis infection and link the cholinergic and gingipain hypotheses of Alzheimer's disease.

Relationship between periodontal disease and male infertility: A case-control study

OBJECTIVES

To compare the prevalence of chronic periodontitis between men who had semen abnormalities and those who had normozoospermia through a case-control study.

MATERIALS AND METHODS

Male patients who visited the assisted reproduction clinic of a large general hospital and were diagnosed with semen abnormalities were included in the case group. The control group was composed of patients of the same clinic with normozoospermia. The semen analysis included sperm concentration, count and progressive and total motility, which were measured in the laboratory. A questionnaire and clinical periodontal examination were conducted for all participants. Logistic regression was performed to explore the relationship between chronic periodontitis and male infertility.

RESULTS

A total of 192 participants were included: 63 participants (32.8%) had some type of semen abnormality (case group), while 129 participants (67.2%) had normozoospermia (control group). The case group had a significantly higher prevalence of moderate/severe periodontitis than the control group (33.3% vs. 17.8%, p = .012). The logistic regression showed that participants who had moderate/severe periodontitis had a greater chance of having semen abnormalities after adjusting for other confounding factors (OR = 3.377, p = .005).

CONCLUSIONS

Periodontitis is associated with semen abnormalities and sperm motility in men.

The State of Men's Health Services in the Veterans Health Administration

PURPOSE OF REVIEW

For many diseases that place a large burden on our health care system, men often have worse health outcomes than women. As the largest single provider of health care to men in the USA, the Veterans Health Administration (VA) has the potential to serve as leader in the delivery of improved men's health care to address these disparities.

RECENT FINDINGS

The VA system has made recent strides in improving benefits for aspects of men's health that are traditionally poorly covered, such as treatment for male factor infertility. Despite this, review of Quality Enhancement Research Initiatives (QUERIs) within the VA system reveals few efforts to integrate disparate areas of care into a holistic men's health program. Policies to unify currently disparate aspects of men's health care will ensure that the VA remains a progressive model for other health care systems in the USA.

"Low Testosterone Levels in Body Fluids Are Associated With Chronic Periodontitis"

There is a debate over the association between low testosterone levels in body fluids and the occurrence of chronic periodontitis (CP). The aim of the present systematic review was to assess whether low testosterone levels in body fluids reflect CP. In order to identify studies relevant to the focus question: “Is there a relationship between low testosterone levels in body fluids and CP?” an electronic search without time or language restrictions was conducted up to June 2016 in indexed databases using different keywords: periodontitis, chronic periodontitis, periodontal diseases, testosterone, and gonadal steroid hormones. A total of eight studies were included in the present systematic review. The number of study participants ranged from 24 to 1,838 male individuals with ages ranging from 15 to 95 years. Seven studies measured testosterone levels in serum, two studies in saliva, and one study in gingiva. Four studies reported a negative association between serum testosterone levels and CP. Two studies reported a positive association between decreased testosterone levels in serum and CP. Increased levels of salivary testosterone among patients with CP were reported in one study; whereas one study reported no significant difference in the concentration of salivary testosterone between patients with and without CP. One study identified significant increase in the metabolism of testosterone in the gingiva of patients with CP. Within the limits of the evidence available, the relationship between low testosterone levels and CP remains debatable and further longitudinal studies and control trials are needed.