Antibacterial activity of povidone-iodine against an artificial biofilm of Porphyromonas gingivalis and Fusobacterium nucleatum.

OBJECTIVE: To investigate the antibacterial activity of povidone-iodine (PVP-I) on an artificial dual species biofilm of periodontal pathogens. DESIGN: Porphyromonas gingivalis or Fusobacterium nucleatum grown in broth culture was inoculated on polycarbonate membrane (PCM) tissue culture inserts. After incubation for 72 h, PVP-I solutions were applied to the biofilm for the time period ranging from 0.5 to 5 min. After addition of a deactivator, each PCM was removed and the biofilm on the PCM was serially diluted and plated on blood agar plates and cultured anaerobically for 7 days. Then viable bacteria were enumerated. RESULTS: In the dual species biofilm model, F. nucleatum showed an approximately 200-fold increase in viable counts when compared with mono-microbial biofilm. In dual species biofilm, PVP-I with concentration equal to or greater than 2% was required to significantly reduce P. gingivalis and F. nucleatum. When the contact time of PVP-I was increased to 1 min or greater, no difference in antibacterial activity of PVP-I was observed in any concentration. CONCLUSION: These results suggest that 30s application of 2% PVP-I would be effective in suppressing both P. gingivalis and F. nucleatum in dual-species biofilm, and this provides clinical implication for the control of subgingival biofilm.

Potential impact of surgical periodontal therapy on oral health-related quality of life in patients with periodontitis: a pilot study.

AIM: To gain insight into the impact of periodontal surgery on oral health-related quality of life (QoL) of patients with periodontitis. MATERIAL AND METHODS: Study participants were recruited from moderate to severe periodontitis patients. After initial periodontal therapy, participants received periodontal surgery. Oral Health-related Quality of Life Model for Dental Hygiene (OHRQL) was used to assess participant's QoL at each time point of periodontal evaluation (baseline, at least 3 weeks after initial therapy and 3-4 months after surgery). RESULTS: A total of 21 patients completed OHRQL assessment after surgery. Compared with baseline, a progressive improvement in periodontal parameters was observed during the periodontal therapy. The total mean OHRQL score at baseline (25.5 ± 11.4) was significantly reduced (improved) after initial therapy and after surgery (16.7 ± 9.5 and 15.0 ± 9.7, respectively; p < 0.01). However, no significant difference was found between the OHRQL score after initial therapy and that after surgery. CONCLUSIONS: No significant differences in patients' oral health-related QoL were observed between post-initial therapy and post-surgery intervals, although a tendency of surgery to determine an improvement in QoL was observed when compared with post-initial treatment.

Effect of initial periodontal therapy on oral health-related quality of life in patients with periodontitis in Japan.

BACKGROUND: It is becoming increasingly important for periodontists and dental hygienists to take a biopsychosocial approach to care when considering periodontal interventions. However, information on how patients perceive periodontitis and its treatment is limited. The purpose of the present study is to gain insight into the patient perception of oral health and the impact that periodontitis and treatment have on self-assessed quality of life (QoL). METHODS: This was a prospective, two-center, clinical study in Japan. Patients with periodontitis were assessed for their perceptions of oral health by using an instrument for oral health-related QoL (OHRQL) before and after initial periodontal therapy. RESULTS: A total of 58 patients (mean age: 53.6 years; 23 male and 35 female) participated in the study and completed initial periodontal therapy. At baseline, 97% of the patients perceived that their oral health status impacted on their QoL in one or more ways. Pain, eating and chewing, and psychologic function were identified as compromised OHRQL domains. More than one-half of the patients rated their overall oral health as poor. Initial periodontal therapy, consisting mainly of oral hygiene instructions and scaling and root planing, significantly improved OHRQL scores (P = 0.0027). The effect size was calculated to be 0.51, indicating a moderate improvement. Compared with baseline, a significantly higher proportion of patients reported rarely or never having a problem regarding OHRQL domains such as pain (P = 0.0049) and eating and chewing (P = 0.0145) after treatment. No significant difference in the OHRQL improvement was found with respect to disease severity. CONCLUSIONS: Periodontitis negatively affected QoL in this population of Japanese patients with periodontitis. Conventional non-surgical periodontal therapy has a potential to ameliorate patient perceptions of oral health.

Improvement of hydrogelation abilities and handling of photocurable gelatin-based crosslinking materials.

Three types of eosin-derivatized gelatins (eosin-gelatins) with different molecular weights (M(w)) of ca. 15 kDa (low-molecular-weight eosin-gelatin, LEG), ca. 30 kDa (medium-molecular-weight eosin-gelatin, MEG), and ca. 95 kDa (high-molecular-weight eosin-gelatin, HEG) were prepared. All the eosin-gelatins except for HEG dissolved completely in water at 37 degrees C within several hours even at high concentrations of 35 or 40 wt % along with polyamine (poly(N,N-dimethylaminopropylacrylamide)) to produce photo-crosslinkable materials. The materials had appropriate viscosity for in situ molding at 37 degrees C and could be handled as a liquid at low temperatures of up to 25 degrees C. Upon photoirradiation for several tens of seconds, the materials were converted almost completely to hydrogels in the desired form with a microporous network structure by the radical coupling reaction. The mechanical strength of the produced hydrogels could be controlled by selecting a particular molecular weight or concentration of eosin-gelatins. The hydrogels obtained from LEG (40 wt %) or MEG (35 wt %) had elasticity similar to that of goat periodontal tissue. The handling of the photo-crosslinkable materials at room temperature and their photogelation ability were drastically improved by reducing the M(w) of eosin-gelatin. The potential usefulness of the photo-crosslinkable materials to periodontal regeneration has been discussed.

Fusobacterium nucleatum enhances invasion of human gingival epithelial and aortic endothelial cells by Porphyromonas gingivalis.

Invasion by Porphyromonas gingivalis has been proposed as a possible mechanism of pathogenesis in periodontal and cardiovascular diseases. Porphyromonas gingivalis have direct access to the systemic circulation and endothelium in periodontitis patients by transient bacteremia. Periodontitis can be described as one of the predominant polymicrobial infections of humans. In the present study, P. gingivalis strains were tested for their ability to invade a human gingival epithelial cell line (Ca9-22) and human aortic endothelial cells in coinfection with Fusobacterium nucleatum using antibiotic protection assays. Coinfection with F. nucleatum resulted in 2-20-fold increase in the invasion of host cells by P. gingivalis strains. The invasive abilities of P. gingivalis strains were significantly greater when incubated with a F. nucleatum clinical isolate (which possesses strong biofilm-forming ability), than when incubated with a F. nucleatum-type strain. In inhibition assays with metabolic inhibitors, a difference in inhibition profiles was observed between mono- and polymicrobial infections. Collectively, our results suggest that F. nucleatum facilitates invasion of host cells by P. gingivalis. Investigations of polymicrobial infection of host cells should improve our understanding of the role of P. gingivalis in periodontal infection and proatherogenic mechanisms.

The efficacy of povidone-iodine products against periodontopathic bacteria.

A total of 8 strains of 6 bacterial species, Porphyromonas gingivalis ATCC33277 and TDC286, Actinobacillus actinomycetemcomitans ATCC29523 and JP2, Fusobacterium nucleatum No. 2, Tannerella forsythensis ATCC43937, Prevotella intermedia ATCC25611 and Streptococcus anginosus ATCC33397, were treated with povidone-iodine (PVP-I) gargle (PVP-I: 0.47 and 0.23% w/v) or chlorhexidine gluconate (CHG) gargle (CHG: 0.002% w/v) for 15, 30 or 60 s, after which they were inoculated into various media, cultured and counted for residual bacteria. At both concentrations, PVP-I gargle reduced the viable cell count of all 8 bacterial strains to below the measurable limit within 15 s. By contrast, there were more than 1,000 viable colonies 60 s following treatment with the CHG gargle. The results demonstrate that povidone-iodine gargle has rapid bactericidal activity against the causative bacteria of periodontal disease.

A case of a slipped medial rectus muscle after strabismus surgery.

BACKGROUND: A slipped muscle after strabismus surgery is a well known complication, but only a few cases have been reported in the medical literature. Here, we report a case of a slipped medial rectus muscle that occurred after strabismus surgery for esotropia. CASE REPORT: The patient was a 10 year old male with an acquired esotropia of 20 PD at distance. For treatment, 3.5 mm bilateral medial rectus recessions was performed. There were no complications during the procedure. On postoperative day 8, the eye position was orthotropic in primary position, but a right exotropia was observed in left gaze. The boy was frequently observed rubbing his right eye after surgery. The right exotropia increased to 30 PD 2 months after surgery. Limited adduction of the right eye, a large widening of the lid fissure on adduction, and mild exophthalmos were observed. Based on the above findings, a slipped medial rectus was suspected, and a second surgery, advancement of the right medial rectus muscle was performed 2.5 months after the initial procedure. After this second procedure, the eyes became orthotropic, and the adduction disorder, large widening the lid fissure, and mild exophthalmos resolved. CONCLUSION: The slipped muscle may have been caused by insufficient suture and/or excessive rubbing of the eye by the patient. When divergent strabismus is observed after recession of the medial rectus muscle, a slipped muscle should be considered as a differential diagnosis.

Gingipains as candidate antigens for Porphyromonas gingivalis vaccine.

Porphyromonas gingivalis (P. gingivalis), a gram-negative anaerobe, is involved in the pathogenesis of periodontal disease, and is found frequently in the subgingival flora in patients with periodontitis. This organism possesses a variety of virulence factors including lipopolysaccharide, capsular material, fimbriae and proteases (enzymes). Among the P. gingivalis antigens, enzymes such as Arginine-specific gingipains (RgpA, RgpB) and lysine-specific gingipain (Kgp) have been studied for their ability to induce biologically significant antibodies. This review summarizes recent information on the gingipains and their possible application in the development of an anti-P. gingivalis vaccine.