Howard Sa

Bio: Howard Sa is an academic researcher. The author has an hindex of 1, co-authored 1 publications receiving 59 citations.

Relationship between the percentage of subgingival spirochetes and the severity of periodontal disease.

Abstract: The purpose of this study was to determine the correlations between various clinical assessments of inflammatory periodontal disease and the percentage of motile bacteria in the subgingival flora of sites representing widely varying states of periodontal disease. Darkfield microscopy was used to determine the percentage of spirochetes and other motile bacteria at two sites from each of 60 volunteers. For each site the following clinical assessments were recorded: Plaque Index (PII), gingival exudate (GE), Gingival Index (GI), bleeding tendency (BT), pocket depth (PD), connective tissue attachment loss (AL) and Periodontal Disease Index (PDI). Statistically significant (P < 0.001) positive correlations (r) were found between the percentage of subgingival spirochetes and PlI (r = 0.54), GE (r = 0.61), GI (r = 0.57), BT (r = 0.59), PD (r = 0.56), AL (r = 0.54) and PDI (r = 0.61). Clinically healthy sites harbored much lower percentages of motile bacteria than did clinically diseased sites. Most of the observ...

Metronidazole in Periodontitis: I. Clinical and Bacteriological Results after 15 to 30 Weeks*

Abstract: The statistical association of certain anaerobic organisms such as black pigmented bacteroides (BPB) species and spirochetes with clinical signs of active periodontitis, i.e. bleeding upon probing and bone loss, suggests that the lesions may actually reflect a "specific infection" involving these or unidentified species. All the known oral species of BPB and spirochetes are anaerobes which suggests that antimicrobial treatment directed specifically against anaerobes might be effective in periodontal therapy. In this report, the short-term results of metronidazole treatment plus mechanical debridement in patients with extensive periodontal disease and of a double-blind clinical study in which metronidazole plus mechanical debridement is compared to placebo plus mechanical debridement are described. The findings indicate that 1 week of systemic metronidazole can optimize the clinical reduction of pockets and increase the apparent attachment in periodontitis patients who receive concurrent mechanical debridement of their root surfaces. In patients with extensive clinical involvement, metronidazole resulted in a significant reduction in the number of sites exhibiting pocket depths and attachment loss greater than or equal to 7 mm. When metronidazole plus mechanical debridement was compared with placebo plus mechanical debridement in a double-blind study, the metronidazole patients exhibited a significant improvement in those sites initially greater than or equal to 7 mm. The beneficial effect of the metronidazole was associated with a significant and sustained reduction of certain anaerobic organisms such as Bacteroides gingivalis and the large spirochetes. These data indicate that treatment aimed specifically toward the anaerobic component of the plaque flora can be associated with impressive clinical improvements 15 to 30 weeks after the initiation of treatment.

Treatment of periodontal infections due to anaerobic bacteria with short‐term treatment with metronidazole

Abstract: In the present report, five selected periodontal patients were treated for 1 week with metronidazole. Two of the patients had their teeth scaled and root-planed the week they received metronidazole. Prior to treatment, B. asaccharolyti cus accounted for 41 % of the cultivable isolates and the spirochetes averaged 29 % of the microscopic count in plaque removed from each of four pockets per patient. The presence of these elevated proportions of periodontopat hic bacteria combined with the presence of periodontal pockets and attachment loss suggested that the patients were in a state of an active infectious pro- cess involving primarily anaerobic bacteria. If this be the case, then antimicrobial therapy directed against these anaerobes with metronidazole was indicated. The 1-week treatment with metronidazole significantly reduced the proportions of these organisms for up to 6 months after treatment. Coincident with these findings was an improvement in the clinical parameters, especially in those sites that initially had greater than 5 mm pocket or at- tachment loss. These sites showed a 2 mm or more reduction in pocket depth and an almost 2 mm gain in apparent attachment that was evident 6 months after treatment. The results obtained were in only five patients. However, the magnitude of improvement suggests that antimicrobial therapy directed against anaerobic organisms may be a valuable adjunct to periodontal therapy.

Hydrogen Peroxide: A Review of Its Use in Dentistry

Abstract: Several dentifrices that contain hydrogen peroxide are currently being marketed. The increased use of bleaching agents containing (or generating) H2O2 prompted this review of the safety of H2O2 when used in oral hygiene. Daily exposure to the low levels of H2O2 present in dentifrices is much lower than that of bleaching agents that contain or produce high levels of H2O2 for an extended period of time. Hydrogen peroxide has been used in dentistry alone or in combination with salts for over 70 years. Studies in which 3% H2O2 or less were used daily for up to 6 years showed occasional transitory irritant effects only in a small number of subjects with preexisting ulceration, or when high levels of salt solutions were concurrently administered. In contrast, bleaching agents that employ or generate high levels of H2O2 or organic peroxides can produce localized oral toxicity following sustained exposure if mishandled. Potential health concerns related to prolonged hydrogen peroxide use have been raised, based on animal studies. From a single study using the hamster cheek pouch model, 30% H2O2 was referred to as a cocarcinogen in the oral mucosa. This (and later) studies have shown that at 3% or less, no cocarcinogenic activity or adverse effects were observed in the hamster cheek pouch following lengthy exposure to H2O2. In patients, prolonged use of hydrogen peroxide decreased plaque and gingivitis indices. However, therapeutic delivery of H2O2 to prevent periodontal disease required mechanical access to subgingival pockets. Furthermore, wound healing following gingival surgery was enhanced due to the antimicrobial effects of topically administered hydrogen peroxide. For most subjects, beneficial effects were seen with H2O2 levels above 1%.

Periodontal diagnosis. Current status and future needs

Abstract: This literature relating to current methods of periodontal diagnosis is reviewed. There exists a future need for objective diagnostic techniques which reflect the dynamics of periodontal disease activity.