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Αbstract Background/Aim: The aim of this study was to investigate healing responses to demineralized freeze-dried bone powder allografts in standardized periodontal fenestration defects, compared with subcutaneous wounds in a dog model. Methods: Circular periodontal fenestration defects were created buccally at all four canines in 14 mongrel dogs. Each site received one of the following underneath a barrier membrane: (a) ethylene oxide (EO)-sterilized demineralized freeze-dried bone allografts (DFDBA), (b) heat-treated DFDBA, (c) non-sterilized DFDBA and (d) ungrafted control. Twelve of the 14 dogs had three subcutaneous chest wall pouches created and one of the three DFDBA materials placed in each. The animals were necropsied at 4 weeks. Histologic sections were prepared through the center of the fenestration sites in an apico-coronal direction. Quantitative analysis using computer-assisted imaging technique was performed. Subcutaneous implants were evaluated histologically and quantified for associated inflammatory cell infiltrate. Results: Fenestration defects healed by partial osseous fill and cementum regeneration with formation of a periodontal ligament. The graft particles generally appeared isolated from the site of osteogenesis and covered by cementum-like substance. Graft particles incorporated into newly formed bone at a distance from the root surface was the exception. No statistically significant differences in new bone formation were observed between treatment groups within animals, but significant inter-animal variation was found (p

Porous coralline hydroxyapatite blocks were implanted in the anterior region of several patients to improve the pontic/ridge relationship for a fixed prosthesis, thereby improving esthetic appearance and oral hygiene performance. A beveled incision on the palate was used to displace the flap coronofacially without leaving an area of denuded bone or graft. Flap margins were sutured to the adjacent palatal tissues. At the 2 1/2- and 3-year postgrafting follow-up, the implant area was healthy and ridge contours have been maintained. The permanent fixed partial denture is functional, and radiographic evaluation indicates the continued presence of the porous coralline hydroxyapatite implant. Three-year results have been promising enough to warrant continuing the procedure in patients requiring localized ridge augmentation.

The purpose of this investigation was to evaluate the histologic response to replamineform (porous) hydroxyapatite grafts in chronically inflamed, surgically created, periodontal pockets in Rhesus monkeys. Forty-eight subcrestal defects were surgically created in 8 Rhesus monkeys. Orthodontic wires were adapted to the base of the defects and left in place for 8 weeks. The defects were randomly assigned a treatment modality so that 8 granular porous and 8 block porous hydroxyapatite grafts were done. Eight sites were left as unoperated controls. Twenty-four contralateral sham-operated sites were treated by open curettage. Histometric measurements of the length of regenerated connective tissue attachment were recorded. Block hydroxyapatite, granular hydroxyapatite, and sham-operated sites exhibited similar amounts of regenerated connective tissue attachment, which was significantly greater than that which occurred in unoperated controls. Newly formed bone was observed within the porous channels of the hydroxyapatite grafts as well as in direct apposition on the surface of implant particles. New bone, cementum, and periodontal ligament was observed in grafted sites and in defects treated by open curettage. In some instances healing occurred by means of a long junctional epithelium. Histology confirmed that unoperated defects remained as unhealed, inflamed periodontal pockets. The results of this study suggest that porous hydroxyapatite grafts have the potential to regenerate the attachment apparatus in primates.

This investigation included a cross-sectional component (284, 20-40-year-old subjects/568 sites) and a longitudinal component (19 subjects with moderate to advanced periodontitis/76 sites). Subgingival plaque samples and clinical data were obtained from all upper second bicuspids and first molars in the longitudinal subjects and from both upper first molars in the cross-sectional subjects. The purpose was to: determine/confirm changes in proportions of selected subgingival microorganisms following root planning combined with conventional oral hygiene procedures in the longitudinal subjects, evaluate those changes in terms of an estimate of the naturally occurring distribution of subgingival microorganisms based on data obtained from the cross-sectional subjects and relate shifts in the subgingival microorganisms to changes in clinical measurements. Changes following treatment at sites with pre-instrumentation probing depths greater than or equal to 4.5 mm included cocci, 18.3 to 46.9%; spirochetes, 20.9 to 3.1%; total motile organisms, 28.5 to 5.9%; Fusobacterium spp., 10.2 to 2.2%; and dark-pigmented Bacteroides spp., 14.0 to 9.7%. Translating proportions of microorganisms in samples from subjects in the longitudinal treatment study to equivalent percentile ranks within the large cross-sectional data base demonstrated that at probing depths greater than or equal to 4.5 mm cocci moved from below the 50th percentile in our estimate of the naturally occurring distribution of subgingival microorganisms to above, and spirochetes, total motile organisms and Fusobacterium spp. moved from above the 50th percentile to below. The microbiological findings were consistent with statistically significant improvements in clinical measurements. Statistically significant changes also occurred in microorganisms at sites with initial probing depths less than 4.5 mm.

The purpose of this study was to evaluate the association between signs of trauma from occlusion, severity of periodontitis and radiographic record of bone support. The maxillary first molars of 300 individuals were independently evaluated by two examiners for signs of trauma from occlusion, pattern or occlusal contacts and severity of periodontitis. Each site was also evaluated radiographically by an independent third examiner. The results indicated that: teeth with either bidigital mobility, functional mobility, a widened periodontal ligament space or the presence of radiographically visible calculus had a deeper probing depth, more loss of clinical attachment and less radiographic osseous support than teeth without these findings, teeth with occlusal contacts in centric relation, working, nonworking or protrusive positions did not exhibit any greater severity of periodontitis than teeth without these contacts, teeth with both functional mobility and radiographically widened periodontal ligament space had deeper probing depth, more clinical attachment loss and less radiographic osseous support than teeth without these findings and given equal clinical attachment levels, teeth with evidence of functional mobility and a widened periodontal ligament space had less radiographic osseous support than teeth without these findings.

This study was designed to examine human subgingival plaque for the presence of dark-pigmented Bacteroides (DPB) species in a large adult population that had been following a rigorous oral hygiene and recall program for 2 years. Subjects received scaling and root planing and oral hygiene instructions at the time of entry and then a prophylaxis and/or oral hygiene instructions at frequent intervals. Clinical measurements were determined and microbial flora identified in subgingival plaque. The DPB species were found in 63% of the subjects and 47% of the total sites. The N-acetyl-B-glucosaminidase-positive DPB species (B. melaninogenicus, B. denticola or B. loescheii), B. intermedius, B. gingivalis and strains of unclassified pigmenting Bacteroides were found in 25, 50, 3 and 40% of the subjects, respectively, and at 15, 35, 2 and 25% of the sites, respectively. Plaque and bleeding indices, probing depth and mean proportions of motile rods and spirochetes were higher at sites with DPB as compared to sites without DPB species. Sites with B. intermedius had higher plaque and gingival indices and greater loss of probing attachment than sites with DPB other than B. intermedius. The prevalence of B. intermedius and other DPB species was high even though subjects were on a rigorous oral hygiene and recall program.

Ideally, the new attachment operation should be confined to subcrestal pockets. The objective of the new attachment operation is to raise the attachment coronally to eliminate the periodontal pocket and to refill the subcrestal defect with new bone. The step-by-step procedure has been described. A partial gingivectomy will remove the marginal epithelium and reduce part of the pocket, namely, a portion of the soft tissue coronal to the alveolar crest. The most common reasons for failure are (1) the lack of complete and thorough root curettage, (2) mobility of the tooth, and (3) leaving some of the soft tissue in the subcrestal defect. If the operation should fail to eliminate the pocket, repetition of the procedures will result in success in the majority of cases. When the alveolar bone refills the subcrestal defect, a new functional periodontal membrane will be formed. This operation, rather than ostectomy or extraction, is the treatment of choice. The new attachment operation can be done successfully by the general practitioner as well as by the periodontist.

The purposes of this 2-year longitudinal study were to: compare the clinical effectiveness of patient applied sodium bicarbonate, hydrogen peroxide, and sodium chloride (S/P) to the use of conventional oral hygiene methods and to investigate the motivational effect of using phase-contrast microscopy in teaching effective oral hygiene. Initially, 972 subjects were screened for signs of periodontitis. From these, 347 with early to moderate periodontitis were selected and each was randomly assigned to one of four home treatment regimens after scaling and root planing. The four treatment regimens included: conventional oral hygiene procedures, conventional oral hygiene procedures plus phase-contrast demonstration of subgingival microbial forms for oral hygiene motivation, S/P oral hygiene, and S/P oral hygiene plus phase-contrast demonstration of subgingival microbial forms for oral hygiene motivation. Plaque, bleeding, gingival inflammation, probing depth, and clinical attachment level were recorded at baseline, 8, 16, and 24 months. Subjects were recalled for reinforcement of oral hygiene and periodontal prophylaxis at various intervals. Data were analyzed based on disease severity, location of index sites and compliance. The results indicated that both conventional oral hygiene procedures and the S/P regimen were effective in reducing clinical signs of disease when combined with professional care. There were no differences between the two regimens in clinical effectiveness and trends favoring microscopic viewing of subgingival plaque for motivational purposes were not statistically significant.

This study of 171 subjects compared the effectiveness of a patient-applied salt and peroxide oral hygiene regimen with the use of conventional oral hygiene methods on clinical measures of periodontal disease, and determined patient compliance with and acceptance of using these two oral hygiene regimens. Results indicated that both regimens, when combined with professional care, were effective in changing clinical measures of periodontal disease to a state favoring periodontal health.

The association between Actinobacillus actinomycetemcomitans and periodontal disease in juveniles has been well documented. The purpose of this investigation was to determine the prevalence and proportions of A. actinomycetemcomitans in supragingival and subgingival plaque samples from the maxillary first molars of a large number of young adults. The study population included 284 adults, aged 20–40, ranging in periodontal disease status from healthy to moderate periodontitis but with the majority exhibiting early periodontal disease. The clinical characteristics of probing depth, attachment level, plaque index, and gingival index were measured. Supragingival and subgingival plaque samples were evaluated microscopically for microbial forms. They were also cultured on supplemented blood agar and various selective agar media including selective media for A. actinomycetemcomitans. The prevalence of A. actinomycetemcomitans in subgingival and supragingival plaque for individuals in the population was 13.0% (37/284) and 4.9% (14/284), respectively. Proportions of actinobacilli, based on total anaerobic counts, were found at or below 1% in 87% of 47 subgingival sites from 37 subjects. Supragingival and subgingival sites with actinobacilli were compared to sites without actinobacilli. Subgingival sites with A. actinomycetemcomitans had a significantly higher mean plaque index, with 79% of these sites having a plaque index greater than 1.0 compared to 30% of sites without actinobacilli. The mean gingival index, probing depth, and attachment level of sites with actinobacilli were also higher, but not significantly, than those without. Of the microbial forms enumerated, only spirochetes had a significantly higher mean proportion at subgingival sites when compared to sites without actinobacilli. Mean proportions of the cultivable microorganisms, Veillonella spp. and Streptococcus spp., were significantly lower at sites with A. actinomycetemcomitans. Differences in the mean proportions of certain microorganisms were compared between the 47 subgingival sites with actinobacilli divided into three groups by probing depth. Mean proportions of A. actinomycetemcomitans were significantly higher at intermediate probing depths between 3.0 and 5.0 mm compared to deeper sites with probing depths above 5.0 mm. On the other hand, dark-pigmented Bacteroides spp. mean proportions were significantly higher at deeper probing depths than at either intermediate or shallow, less than or equal to 3.0 mm, probing depths. There were no significant differences in the mean proportions of spirochetes between shallow, intermediate, or deeper probing depths of the 47 subgingival sites with actinobacilli.