Fatih Oğuz MD; Abubekir Eltas DDS, PhD; Ali Beytur MD; Ender Akdemir MD; Mustafa Özay Uslu; Ali Güneş MD
ONLINE: December 4, 2012 – The Journal of Sexual Medicine,
Erectile dysfunction (ED), a man’s inability to have an erection suitable for sexual intercourse, is thought to affect an estimated 150 million men worldwide. ED has several possible causes, which can be organic, psychological, or a combination of these. In about 65% of cases, an organic cause is the culprit; vascular dysfunction is the most common organic cause. Emotional stress and depression can also lead to ED.
Chronic periodontitis (CP) refers to a group of infectious diseases caused mostly by bacteria. CP involves inflammation of the gingival tissues and may affect structures that support teeth. Past research suggests that CP leads to endothelial dysfunction, which may cause systemic vascular diseases, such as coronary heart disease, cerebrovascular disease, and chronic obstructive pulmonary disease.
Researchers have found a high prevalence of CP in patients with ED and a strong relationship between the two conditions. However, it is not known how the severity and type of CP affects erectile function. This case-controlled study looked at the relationship between the severity of ED and CP and the correlation between clinical periodontal parameters and ED.
Materials and Methods
This study was a single-blinded, randomized-controlled clinical trial. One group of 80 male participants presented with ED. The control group consisted of 82 men without ED. All of the men were between 30 and 40 years old. After determining their erectile function status, the men’s periodontal health was assessed.
Men were excluded if they had a systemic disease that could affect ED or periodontal health, such as diabetes mellitus, heart disease, or hypertension. Other exclusion criteria were smoking, having periodontal treatment within the last 12 months, and taking antibiotics within the last 6 months.
International Index of Erectile Function (IIEF) Questionnaire
Questions 1-5 and 15 from the International Index of Erectile Function (IIEF) were used to assess ED. Scores above 30 indicated normal erectile function; scores lower than or equal to 25 indicated ED. Subjects with scores of 26 to 29 were excluded to ensure that the men truly had normal function or ED. The IIEF questionnaire was used to evaluate sexual function. Men who reported low or medium erectile confidence were categorized as having ED. Those who had high confidence were excluded. The same clinician explained the questionnaire to all participants.
A previously calibrated periodontist examined each participant to assess periodontal health and evaluated the following:
• Plaque index (PI) – measurement of soft debris and mineralized deposits
• Bleeding on Probing (BoP) – bleeding gums or gingival bleeding, a sign of inflammation
• Probing Depth (PD) – the distance between the gingival margin and the deepest aspect of the pocket
• Clinical Attachment Level (CAL) – the distance between the cementoenamel junction of the tooth and the deepest aspect of the pocket
Full-mouth bleeding scores were determined by the presence or absence of bleeding after PD was measured.
All measurements were taken on 6 surfaces per tooth in all teeth except the third molars.
Periodontal health was defined as the lack of PD ≥ 4 mm. Men who had 1-15 tooth sites with ≥ 4 mm PD and BoP were considered to have mild periodontal disease; those who had ≥ 15 tooth sites with ≥ 4 mm PD and BoP were classified as having severe disease.
The World Health Organization’s decayed, missing, filled teeth index (DMFT) was also used.
Key results included the following:
• The non-ED group consisted of 82 men with a mean age of 35.7 ± 4.8 years.
• The ED group included 80 men with a mean age of 34.9 ± 4.9 years.
• Twenty-three percent of the men in the non-ED group had severe chronic periodontitis.
• In the ED group, 53% of the men had severe CP.
• Logistic regression analysis showed a highly significant association between ED and the severity of CP.
• After adjusting for potential cofounders, men with severe CP were 3.29 times more likely to have ED than the men without CP.
• The men in the ED group had higher mean values for PI, BoP, and higher percentages of sites with PD > 4 mm and sites with CAL > 4 mm. Their DMFT scores were also significantly higher than those of the non-ED group.
• Using Pearson’s chi-square test, the researchers found positive correlations between DMFT, PI, BoP and the percentage of sites with PD > 4 mm and the percentage of sites with CAL > 4 mm with ED. No correlation was found between the mean PD and CAL with ED.
The authors noted that risk factors for atherosclerosis can predispose a person to endothelial dysfunction.
Atherosclerosis can lead to ED. However, problems with endothelial function and smooth muscle relaxation can also contribute to ED. Endothelial dysfunction involves obstructive vascular changes which can result in vascular problems. “Endothelial dysfunction is the first step of vascular pathology,” the authors wrote.
The study results support the hypothesis that CP identified by the presence of
PD > 4 mm and CAL > 4 mm and the increased percentage of sites with BoP is linked to an increased risk for ED.
Aging, smoking, diabetes mellitus, and coronary artery disease appear to be risk factors for both ED and CP. This is why men who were smokers or had systemic disease were excluded from the study. Men between the ages of 30 and 40 were chosen so that the effects of aging would not be prominent.
While past research has examined the higher prevalence of CP among men with ED, there has not been much information on how CP is involved with the pathophysiology of ED. The current study aimed to examine this more closely.
Systemic inflammation caused by periodontitis contributes to atherosclerosis through the activation of a biochemical reaction cascade, plaque formation, and injury of the endothelium. Research by Blum et al. has suggested that treating periodontitis may improve endothelial function and reverse endothelial dysfunction in patients with periodontitis, thus preventing future cardiovascular disease.
The current study shows that CP is present more often in men with ED than in men without ED. It also suggests that CP may increase endothelial dysfunction. The authors propose three mechanisms that explain this:
• Chronic inflammation in endothelial dysfunction is associated with an increase in reactive oxygen species. Excessive production of reactive oxygen species causes an increase in nitric oxide (NO) inactivation. The damage to the antioxidant system may contribute to endothelial dysfunction in patients with periodontitis.
• High levels of inflammatory mediators may be associated with an increased risk of endothelial dysfunction, resulting in increased inflammatory markers in patients with CP.
• Periodontal pathogens or their products could affect endothelial function directly.
In the current study, the researchers did not assess endothelial dysfunction. However, BoP was considered an indicator of clinical inflammation. “The higher level of BoP seen in the ED group in our study compared with the control group and the correlation between BoP and ED support the earlier reports that a high level of infection results in ED due to endothelial dysfunction,” the authors wrote.
Findings on the percentage of PD and CAL sites greater than 4 mm, the DMFT scores in the ED group compared to the control group, and the correlation between ED and these parameters support the relationship between ED and CP. Alterations in parameters were due to periodontal infection caused by a patient’s poor oral hygiene.
Limitations of the study included not evaluating endothelial dysfunction and not assessing the severity of ED or the underlying cause.
This study demonstrated the association between clinical periodontal parameters and ED. It suggested that periodontal inflammation can be associated with ED. The authors suggest that periodontal diseases be considered when evaluating young adults with ED.