Evaluation of a surgical debridement bur for use in periodontal surgery.

The Evian Debridement Bur facilitates two fundamental techniques in periodontal surgery--soft-tissue debridement and root planing. The bur debrides granulation and other soft tissues attached to the root or bone and removes hard deposits from root surfaces. It can also be used as an adjunct while performing crown-lengthening procedures and endodontic surgery. The bur is made with blunted flutes and, if used with a relatively light touch, will not cut into the alveolus and will not damage the tooth surface. This article reviews the use and advantages of this bur and shows its effect on the root surface at the ultrastructural level.

One-stage surgery with a nonsubmerged implant system.

Although nonsubmerged implant surgery can reduce patient trauma and costs by eliminating the uncovering procedure, one-piece implants cannot be shortened for esthetic results. However, a new implant design that comes preattached on a multipurpose collar is used for insertion, nonsubmerged healing, and as an abutment base. For submucosal margins, the collar can be replaced by an esthetic abutment that connects directly to the implant. Surface treatments include midsections roughened by hydroxyapatite or titanium plasma spray coatings, with smoother, acid-etched necks and self-tapping apical ends. Screw-retained, friction-fit abutments offer prosthodontic stability and uniformity, despite the submucosal implant type.

A comparison of hydroxyapatite-coated Micro-Vent and pure titanium Swede-Vent implants.

This article compares the survival rates of two root-form implants-hydroxyapatite-coated (HA-coated) Micro-Vent and pure titanium Swede-Vent implants-during a 6-year period. A total of 390 implants were placed in 166 patients aged 18 to 81 years. Fifteen implants were lost before prosthesis placement, and one was lost after prosthesis loading. The overall success rates were 96.8% for the HA-coated Micro-Vent implants and 95.2% for the titanium Swede-Vent implants. The survival rates were similar for both the maxilla and the mandible and for the anterior and the posterior areas. Although most of the HA-coated implants were generally placed in types III and IV bone, results indicated that the survival rate was similar to that of pure titanium implants, which were placed more often in types I and II bone.

Direct replacement of failed CP titanium implants with larger-diameter, HA-coated Ti-6Al-4V implants: report of five cases.

Failure to osseointegrate traditionally mandates immediate implant removal, followed by a 1-year healing period before placing a second implant into the same area. This report presents five cases in which failed screw-type, commercially pure titanium implants were immediately replaced by ledge-type, hydroxyapatite-coated, Ti-6Al-4V implants in the same sockets. These cases suggest that the 1-year healing period may not be necessary, provided that (1) the socket can be reprepared to eliminate thread grooves and invasive soft tissue, (2) the replacement implant is larger in diameter than the original implant, and (3) sufficient available bone remains for the procedures.

Autogenous gingival grafts as epithelial barriers for immediate implants: case reports.

The purpose of this study was to evaluate the use of autogenous gingival grafts as barriers for endosseous implants placed directly into fresh extraction sockets. This study consisted of four patients who presented with hopeless teeth due to endodontic pathology, caries, or root resorption. In all cases, the teeth in question were extracted at the Stage 1 surgery. An endosseous root form implant was immediately placed into the extraction socket in each case. As a consequence of immediate placement, there was a lack of primary closure over the fixture and a large space was present between the fixture and the remaining alveolus. An autogenous gingival graft was sutured in place to cover the fixture and act as a physical barrier to epithelium, food debris, and possibly bacteria. At the Stage 2 surgery, all implants achieved complete osseointegration clinically and radiographically. The results at 16 to 24 months reveal continued success in all four cases. This report demonstrates the potential of autogenous gingival grafts in immediate implant placement. A clinical trial to fully assess the potential of this procedure is recommended.

Altered passive eruption: the undiagnosed entity.

Excessive gingiva can result from delayed or altered tooth eruption. This condition should be considered in restorative dentistry, orthodontic and esthetic treatment.

Use of a root-form implant as a dental pin in a submerged canine for prosthesis support: a case report.

A cavity was prepared in a submerged and impacted maxillary canine in the location of a missing lateral incisor. An 8-mm-long Screw-Vent implant was threaded into the site to function as a dental pin via mechanical retention. A Swede-Vent implant was placed in the area of the adjacent central incisor. After a 6-month submerged healing period, the Swede-Vent implant had clinically osseointegrated, and no breakdown of the dental tissue around the Screw-Vent implant was observed. The implants were restored with a two-unit splinted fixed prosthesis.

Serum IgA and IgG antibodies to Treponema vincentii and Treponema denticola in adult periodontitis, juvenile periodontitis and periodontally healthy subjects.

13 patients with untreated adult periodontitis (AP) were compared to 8 subjects free of periodontal disease (H) with respect to plaque index (PlI), gingival index (GI), probing depth (PD) and differential counts of subgingival bacterial morphotypes from a pooled sample of 6 surfaces with the greatest probing depth. Serum antibody levels to T. vincentii and T. denticola strains were also determined in these subjects as well as in the sera from 5 subjects with localized juvenile periodontitis (LJP). Subjects with AP had significantly elevated proportions of spirochetes and motile rods and lower proportions of coccoid cells than H subjects. They also exhibited significantly higher PlI and GI scores and greater probing depths. Antibody levels were normalized against a standard serum and expressed as ELISA units (EU). IgA and IgG antibody levels to all tested spirochete strains were significantly elevated in AP subjects as compared to subjects in group H or subjects with LJP. No significant differences in antibody titers were detectable between the H and LJP groups with respect to any of the tested strains. No significant correlation could be demonstrated between serum antibody titers to any of the oral spirochete strains tested and the proportions of oral spirochetes determined microscopically.

Comparative longitudinal study of 2 methods of scheduling maintenance visits; 2-year data.

This report compares the clinical and microbiological status of 2 groups of subjects with treated periodontis on different maintenance schedules. 43 control (C) subjects were given prophylaxes every 3 months. 40 test (T) subjects were given this service on a flexible schedule according to the proportions of spirochetes and/or motile rods in fresh smears of subgingival scrapings. Both groups were examined every 6 months clinically and microbiologically. This report presents base line, 1- and 2-year data. Generally, mean values for both groups did not differ significantly from one another. Both groups exhibited comparable increases in GI and PLI scores during the first 2 years of this study. No change in probing depth was noted between base line and the 2-year examination. However, a slight increase in attachment level, as determined by probing, was noted in both groups. Both groups also exhibited similar proportions of bacterial morphotypes at base line and subsequent examinations. Disease recurrence, defined as an increase in probing depth of 3 mm or more from base line on any tooth surface during the 2-year period, tended to be more prevalent in the C than in the T group (15/43 C and 9/40 T subjects). However, the proportional difference between the groups was not statistically significant. Subjects with disease recurrence in the T group had greater proportions of spirochetes at base line than subjects in the same group without disease recurrence (20.2% versus 9.8%, p less than 0.01). This difference in proportions persisted if both groups were examined jointly, but was only of borderline significance (16.0% versus 10.5%, p = 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Ultrastructure of durapatite-periodontal tissue interface in human intrabony defects.

The ultrastructure of the interface between Durapatite (hydroxylapatite) and human periodontal tissues was examined. Durapatite was implanted into the intrabony periodontal defects during periodontal surgery. Reentry procedures were performed after 1 year and the tissues in the defects were biopsied and processed for transmission electron microscopy. Nineteen tissue blocks from four patients were examined, 17 contained Durapatite particles embedded in fibrous tissue and two contained particles encased in bone, all without inflammation. The fibrous connective tissue consisted of densely packed collagen fibrils surrounding the implant particles. The bone surrounding the Durapatite consisted in one case of relatively mature bone, and in the other of osteoid tissue. A granular, amorphous, collagen-free, electron-dense layer was routinely observed between implant and tissue. This layer was thicker in the bone-encased samples than in those surrounded by fibrous connective tissue. Except for the particle surrounded by mature bone, this layer was continuous with an organic meshwork located on the periphery of the implant spaces. The ultrastructural features of the interface are consistent with the existence of a mucopolysaccharide "bonding zone" described by other investigators. The organic meshwork appears to outline areas similar in size and shape to the individual crystallites of hydroxylapatite. This may indicate that the reactive surface of hydroxylapatite is much larger than merely the exterior surface of the implant, a finding which may explain the apparently good tissue adhesion to the implant.

Comparative differential dark-field microscopy of subgingival bacteria from tooth surfaces with recent evidence of recurring periodontitis and from nonaffected surfaces.

Ninety-two subjects with a history of treatment for chronic periodontitis were monitored on a regular basis for an average period of 10.7 months. During this monitoring period, in spite of their participation in a preventive maintenance program, 19 subjects out of 92 showed evidence of significantly increased probing depth (greater than or equal to 3 mm from base line measurements) on at least one tooth surface, or approximately 1% of the dental units at risk in this population. A comparison of differential microscopic counts of subgingival bacteria from the affected tooth surfaces with a pooled sample of 6 other surfaces with the greatest probing depth, in the same mouth, taken at the same appointment, revealed no significant differences between proportions of coccoid cells, spirochetes, motile rods or other cell types. These findings suggest that disease recurrence, as measured by a comparatively rapid increase in probing depth, might be accounted for on the basis of the following hypotheses: an alteration in the host response without a detectable change in the composition of the subgingival microbiota, a qualitative change in the microbial flora not detectable by a microscopic assay, relatively brief episodes of disease activity which may be accompanied by brief, transient, qualitative changes in the local microbiota that cannot be readily detected by biannual examinations.

Bacterial variability within diseases periodontal sites.

The purpose of this study was to examine the variability in bacterial proportions between individual periodontal sites in patients with chronic periodontitis by means of differential dark-field microscopy. Fourteen patients with untreated, moderate to advanced disease were included. Probing depth, plaque and gingival index scores were recorded for each patient. Microbial samples were collected from the tooth surface with the greatest proving depth in each sextant and examined individually by dark-field microscopy. The results indicated that proportions of spirochetes and motile rods at any given probing depth varied considerably, ranging from those expected at healthy sites to those expected at diseased sites. In accordance with previous studies, mean percentages of spirochetes tended to vary directly with increased PD, PlI and GI scores, while mean percentages of coccoid cells tended to follow a reverse pattern. However, no significant correlations could be demonstrated when measurements from individual sites were analyzed. Most of the variance in the data was due to differences between subjects rather than differences between sites. It is postulated that the large variance between subjects and sites is due in part to the cyclical nature of the disease and to the lack of synchrony between remissions and exacerbations at different sites and in different patients.

The osteogenic activity of bone removed from healing extraction sockets in humans.

Cores of bone from healing extraction sites were studied at time intervals of 4, 6, 8, 10, 12 and 16 weeks. The results revealed that between 4 and 8 weeks proliferation of cellular and connective tissue elements occur within the healing socket. Islands of new bone with an osteoid seam surrounded by osteoblasts are present within the connective tissue. From 8 to 12 weeks the bone undergoes maturation and forms a trabecular pattern. Although less pronounced, and osteoid seam is still present and osteoblasts occur in fewer numbers. By 12 to 16 weeks the bony trabeculae are mature with very little osteoid and few osteoblasts. This bone resembles alveolar trabecular bone. Two phases of bony regeneration are apparent from the present study. From 4 to 8 weeks there is a progressive osteogenic phase with proliferation of osteogenic cells and immature bone formation. From 8 to 12 weeks the osteogenesis slows down and the trabeculae mature and increase in volume. From 12 to 16 weeks the bone appears to stabilize with an established alveolar trabecular bone being present. Very little osteogenesis occurs as evidenced by minimal or no osteoid seam with only occasional osteoblasts. It is apparent that in the period between 8 and 12 weeks a substantial quantity of relatively mature well formed bone is present which contains osteoblasts and an osteoid seam. This appears to be an optimal time period to secure bone from a healing extraction site for grafting purposes.

Juvenile periodontitis - healing following therapy to control inflammatory and traumatic etiologic components of the disease.

A case of localized juvenile periodontitis with bone loss affecting molars and premolars with advanced destruction around the lower first molars is described. These lesions were associated with areas of excess occlusal trauma. The ramifications of combined therapy aimed at the elimination and control of both the inflammatory and occlusal components of the disease are discussed relative to the successful treatment of this case. A description of the periodontal status of a sibling of the patient has been included. Extensive defects are associated with the anterior teeth and in this case the patient presented with excessive trauma in the anterior region. Considering the localities of the disease and the similarities between the inflammatory components in both cases, a link between occlusal trauma and juvenile periodontitis is discussed.