Site-level progression of periodontal disease during a follow-up period.

Periodontal disease is assessed and its progression is determined via observations on a site-by-site basis. Periodontal data are complex and structured in multiple levels; thus, applying a summary statistical approach (i.e., the mean) for site-level evaluations results in loss of information. Previous studies have shown the availability of mixed effects modeling. However, clinically beneficial information on the progression of periodontal disease during the follow-up period is not available. We conducted a multicenter prospective cohort study. Using mixed effects modeling, we analyzed 18,834 sites distributed on 3,139 teeth in 124 patients, and data were collected 5 times over a 24-month follow-up period. The change in the clinical attachment level (CAL) was used as the outcome variable. The CAL at baseline was an important determinant of the CAL changes, which varied widely according to the tooth surface. The salivary levels of periodontal pathogens, such as Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans, were affected by CAL progression. "Linear"- and "burst"-type patterns of CAL progression occurred simultaneously within the same patient. More than half of the teeth that presented burst-type progression sites also presented linear-type progression sites, and most of the progressions were of the linear type. Maxillary premolars and anterior teeth tended to show burst-type progression. The parameters identified in this study may guide practitioners in determining the type and extent of treatment needed at the site and patient levels. In addition, these results show that prior hypotheses concerning "burst" and "linear" theories are not valid.

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.