Is loss of attachment due to root planning and scaling in sites with minimal probing depths a statistical or real occurrence?

BACKGROUND: Following root planing and scaling many studies have implied an association between a loss of clinical attachment at sites with initially shallow pockets (1 to 3 mm) and gains in attachment level for deeper probing depths. However, these effects are also consistent with a statistical phenomenon referred to as regression towards the mean. This principle suggests that extreme values will moderate the next time they are recorded. The purpose of this report was to estimate the effect that regression towards the mean has on perceived changes in attachment level after root planing and scaling. METHODS: During the initial examination, 2 different investigators conducted 2 full-mouth probings. Two quadrants were randomly selected to be root planed and scaled until the root surfaces were smooth by tactile touch of an explorer. The 2 remaining quadrants were not treated. At 4 to 6 weeks after treatment, another full mouth probing was done. An examiner who was blind to the quadrants that had been scaled measured attachment level and probing depth after therapy. This study design provided periodontal measurements before and after root planing and scaling, measurements before and after a period of 4 to 6 weeks of no therapy, and duplicate measurements at the beginning of the study. RESULTS: Using the repeat examination when no true change could occur, shallow sites (< or =3 mm of probing depth) showed average negative differences between repeat attachment level measurements (-0.23 mm), which mimicked loss of periodontal attachment. Deep sites, (>6 mm) showed average positive values (0.40) mimicking gain in attachment level. These results suggest that regression towards the mean is a significant effect in this data set. Both shallow non-scaled and scaled sites had similar differences in repeat measures (-0.28 mm, -0.25 mm) which were also similar to and not statistically different from changes after therapy for both non-scaled (-0.21 mm) and scaled sites (-0.08 mm). Thus not only does this data set exhibit regression towards the mean, but it explains the majority of perceived loss of periodontal attachment after scaling at sites that have minimal probing depth. CONCLUSIONS: These results suggest that the majority of perceived loss of attachment due to scaling at sites of minimal probing depth that have been reported in many studies may be due a statistical phenomenon called regression towards the mean.

Treatment of human mucogingival defects utilizing a bioabsorbable membrane with and without a demineralized freeze-dried bone allograft.

BACKGROUND: The use of guided tissue regeneration (GTR) has become an effective procedure for the treatment of gingival recession. No reports exist on the use of a bioabsorbable membrane in combination with a demineralized freeze-dried bone allograft (DFDBA) for the treatment of these defects. METHODS: Fourteen (14) patients with 17 recession defects were included in this clinical study. Each patient had at least 1 tooth with 3 mm or greater marginal tissue recession on the facial surface as measured from the cemento-enamel junction (CEJ). Each patient was treated by GTR using a bioabsorbable membrane. When the first patient presented for inclusion in the study, a coin was flipped to determine if the tooth being treated would be a test tooth (DFDBA) or a control tooth (no DFDBA). Each subsequent patient was alternated between test and control. Immediately prior to the surgical procedure, measurements were made which included recession depth, recession width at the widest point, probing depth, amount of keratinized tissue, and marginal tissue thickness. Local anesthesia was administered, and a measurement from the CEJ to the bone crest was made by sounding through the attachment. RESULTS: The mean initial recession for all defects was 3.35 mm (SD +/- 0.49) and at 6 months postsurgery, mean recession was 0.47 mm (SD +/0.62). This correlated to 86% root coverage for both treatments. For all defects treated, there was a statistically significant increase in keratinized tissue (mean 0.88 mm) and tissue thickness (mean 0.47 mm) and a significant decrease in probing bone level (mean 0.76 mm). No statistically significant differences were observed between groups for any parameter. CONCLUSIONS: Although only 14 subjects with 17 defects were included in this study, the results suggest that the treatment of human gingival recession with a bioabsorbable membrane with or without the use of DFDBA results in significant root coverage, and slight, but significant improvements in keratinized tissue, tissue thickness, and bone level. The greatest limitation of the study was its lack of statistical power. Twenty-two (22) subjects would have been required for the results of the study to show equivalence between groups.

Hydroxyapatite cement implant for regeneration of periodontal osseous defects in humans.

A newly developed calcium phosphate cement used to promote bone regeneration in craniofacial defects was examined to determine its potential for treatment of periodontal osseous defects. Sixteen patients with moderate to severe periodontal disease and 2 bilaterally similar vertical bony defects received initial therapy including scaling and root planing followed by treatment with either calcium phosphate cement, flap curettage (F/C) or debridement plus demineralized freeze-dried bone allograft (DFDBA). Standardized radiographs were exposed at baseline and 12 months postsurgery for computer assisted densitometric image analysis (CADIA). The extent of the bony defect was determined during initial and 12 month re-entry surgery. Within 6 months of implant placement, 11 of 16 patients treated with calcium phosphate cement exfoliated all or most of the implant through the gingival sulcus. At all 16 test sites, a narrow radiolucent gap formed by 1 month postsurgery at the initially tight visual interface between the radiopaque calcium phosphate cement and the walls of the bony defect. Mean probing depth reduction and clinical attachment gain at sites treated with calcium phosphate cement were 1.6 mm and 1.3 mm, respectively at 1 year. Minimal bony defect fill was accompanied by mean crestal resorption of 1.4 mm. Alveolar crestal resorption at sites with calcium phosphate cement was statistically significant (P=0.001). These findings contrasted with the more favorable outcomes for controls treated with DFDBA or F/C. DFDBA sites exhibited probing depth reduction of 3.1 mm, clinical attachment gain of 2.9 mm, and defect fill of 2.4 mm. Respective clinical changes at F/C sites were 2.4 mm, 1.4 mm, and 1.1 mm. CADIA revealed clinically significant trends between the three treatment modalities at various areas-of-interest. Based on the findings of this study, there is no rationale available to support the use of hydroxyapatite cement implant in its current formulation for the treatment of vertical intrabony periodontal defects.

Effects of guided bone regeneration around commercially pure titanium and hydroxyapatite-coated dental implants. II. Histologic analysis.

The purpose of this study was to determine which treatment of a large osseous defect adjacent to an endosseous dental implant would produce the greatest regeneration of bone and degree of osseointegration: barrier membrane therapy plus demineralized freeze-dried bone allograft (DFDBA), membrane therapy alone, or no treatment. The current study histologically assessed changes in bone within the healed peri-implant osseous defect. In a split-mouth design, 6 implants were placed in edentulous mandibular ridges of 10 mongrel dogs after preparation of 6 cylindrical mid-crestal defects, 5 mm in depth, and 9.525 mm in diameter. An implant site was then prepared in the center of each defect to a depth of 5 mm beyond the apical extent of the defect. One mandibular quadrant received three commercially pure titanium (Ti) screw implants (3.75 x 10 mm), while the contralateral side received three hydroxyapatite (HA) coated root-form implants (3.3 x 10 mm). Consequently, the coronal 5 mm of each implant was surrounded by a circumferential defect approximately 3 mm wide and 5 mm deep. The three dental implants in each quadrant received either DFDBA (canine source) and an expanded polytetrafluoroethylene membrane (ePTFE), ePTFE membrane alone, or no treatment which served as the control. Clinically, the greatest increase in ridge height and width was seen with DFDBA/ePTFE. Histologically, statistically significant differences in defect osseointegration were seen between treatment groups (P < 0.0001: DFDBA/ePTFE > ePTFE alone > control). HA-coated implants had significantly greater osseointegration within the defect than Ti implants (P < 0.0001). Average trabeculation of newly formed bone in the defect after healing was significantly greater for HA-coated implants than for titanium (P < 0.0001), while the effect on trabeculation between treatments was not significantly different (P = 0.14). Finally, there were significantly less residual allograft particles in defect areas adjacent to HA-coated implants than Ti implants (P = 0.0355). The use of HA-coated implants in large size defects with DFDBA and ePTFE membranes produced significantly more osseointegration histologically than other treatment options and more than Ti implants with the same treatment combinations. The results of this study indicate that, although the implants appeared osseointegrated clinically after 4 months of healing, histologic data suggest that selection of both the implant type and the treatment modality is important in obtaining optimum osseointegration in large size defects.

Effects of guided bone regeneration around commercially pure titanium and hydroxyapatite-coated dental implants. I. Radiographic analysis.

The purpose of this study was to determine which treatment of a large osseous defect adjacent to an endosseous dental implant would produce the greatest regeneration of bone and degree of osseointegration: barrier membrane therapy plus demineralized freeze-dried bone allograft (DFDBA), membrane therapy alone, or no treatment. The current study assessed radiographic density changes in bone within the healed peri-implant osseous defect. In a split-mouth design, 6 implants were placed in edentulous mandibular ridges of 10 mongrel dogs after preparation of 6 cylindrical mid-crestal defects, 5 mm in depth and 9.525 mm in diameter. An implant site was then prepared in the center of each defect to a depth of 5 mm beyond the apical extent of the defect. One mandibular quadrant received three commercially pure titanium (Ti) screw implants (3.75 X 10 mm), while the contralateral side received three hydroxyapatite (HA) coated root-form implants (3.3 X 10 mm). Consequently, the coronal 5 mm of each implant was surrounded by a circumferential defect approximately 3 mm wide and 5 mm deep. The three dental implants in each quadrant received either DFDBA (canine source) and an expanded polytetrafluoroethylene membrane (ePTFE), ePTFE membrane alone, or no treatment (control). Standardized radiographs were taken at 1 week and 4 months post-implant placement. Computer-assisted densitometric image analysis (CADIA) was performed at 6 areas of interest (coronal, middle, and apical defect areas mesial and distal to each implant) for each of the implant sites. Significantly greater increase in bone density was obtained using DFDBA/ePTFE compared to ePTFE alone or the controls; likewise, ePTFE alone resulted in greater bone density change than the controls. There were no significant differences in radiographic bone density adjacent to Ti versus HA-coated implants. When 3 dogs having postoperative membrane complications were eliminated from the analysis, the results were similar with the exception that defects adjacent to Ti implants had significantly less density gain when compared to HA-coated implants. The results of this study indicate the use of DFDBA/ePTFE in large surgically-created defects promotes a denser healing of bone adjacent to implants when measured radiographically than either ePTFE alone or no treatment.

A comparative study of the effects of metallic, nonmetallic, and sonic instrumentation on titanium abutment surfaces.

This study compared the effects of metallic, nonmetallic, and sonic instrumentation on titanium abutment surfaces in vitro. Designated test surfaces in each of seven abutments were instrumented either for 25 strokes or 30 seconds, and for 50 strokes or 5 minutes. One abutment served as an untreated control. Scanning electron microscopy photomicrographs were coded and scored by five investigators and designated as smooth (comparable to control (0), slightly roughened, (1), moderately roughened (2), or severely roughened (3). Based on this investigation, the increasing order of surface alteration for each instrumentation was as follows: Implacare < Implant Support < Steri-Oss < Dynatip < Columbia 13/14 < Sonic scaler < Implarette scaler. The Implacare and Implant Support nonmetallic (plastic) scalers appear to be the instruments of choice for debridement of titanium abutment surfaces if preservation of surface integrity is the primary objective.

Periodontitis in the baboon: a potential model for human disease.

Advances in periodontics with respect to disease activity, microbiology and immunology have demonstrated the multifactorial nature of periodontal diseases. This serves to underscore the need for an ideal animal model for periodontal research. Non-human primates are most similar to man in comparison to other animal models. The baboon is an Old World monkey that has infrequently been used in periodontal research. Periodontal exams were accomplished on 116 baboons (Papio anubis, P. cynocephalus) ages 5 to 30 years with one baboon year being roughly equivalent to 3 to 4 human years. The study population consisted of 29 males and 87 females. Clinical parameters including probing depth, attachment level, mobility, plaque index and gingival index were collected. Radiographs were taken on 25 animals and correlated to clinical findings. Results showed a significant increase in mean probing depth and mean attachment level with age (p = 0.0001). Disease prevalence and severity were not significantly different between genders. Mobility was uncommon; however, the prevalence and severity of furcation involvement increased with age. Radiographs suggested horizontal and isolated vertical bone loss. Plaque and gingival indices were at sustained high levels for all age groups and showed a statistically significant increase with age. Some baboons were found to develop a naturally-occurring periodontitis that increased in severity with age. This primate may be a suitable model for studies in human periodontal disease.

Observations of root surfaces from patients with early-onset periodontitis and leukocyte adhesion deficiency.

The purpose of this investigation was to report observations of the root surfaces of teeth from 2 siblings with leukocyte adhesion deficiency (LAD). In previous publications, the clinical, radiographic and immunologic findings in the family were presented. 38 permanent teeth from the 2 siblings were prepared for microscopic examination, 11 for light microscopy (LM), and 27 for scanning electron microscopy (SEM). In addition, 8 healthy teeth obtained from 2 patients requiring extractions for orthodontic treatment served as controls. LM observations on healthy teeth revealed cementum with normal structural appearance which exhibited a mosaic or mogul-like pattern with SEM. In LAD specimens, cementum apical to the dentogingival junction exhibited resorption lacunae and areas of poor structural definition characterized by aplasia and hypoplasia (hypomineralization). Areas of hypoplasia presented as distinct irregular surfaces with a pebbly or globular-like appearance. Alteration in cementum formation and maturation may play a role in the etiology of early-onset periodontitis.

Use of furcal bone sounding to improve accuracy of furcation diagnosis.

Accurate diagnosis of periodontal destruction in the furcation region of multi-rooted teeth is a critical component of treatment planning, with different therapeutic approaches chosen based upon clinical determination of the severity of involvement. The current study assessed both vertical and horizontal depths of 274 furcations from 67 patients at three separate time points: by probing prior to anesthesia, by bone sounding after administration of anesthesia, and by direct measurement at the time of surgery. All measurements were made to the nearest millimeter. The mean vertical (1.8 mm) and horizontal (2.16 mm) furcation depths determined prior to anesthesia were significantly less than surgical measurements (2.79 mm and 3.65 mm, respectively). Use of sounding significantly improved the mean accuracy of vertical (2.40 mm) and horizontal (3.11 mm) furcation depth measurements relative to surgical determinations (P = 0.000). Surgical vertical depth was exactly the same as pre-anesthesia probing in 42% of furcations, within +/- 1 mm in 72.3% and within +/- 2 mm in 83.6%. Use of post-anesthesia sounding improved agreement in vertical measurements to 59.5%, 85.7%, and 93.1%, respectively. Surgical horizontal depth was exactly the same as pre-anesthesia probing measurements in 47.1% of furcations, within +/- 1 mm in 68.3% and within +/- 2 mm in 77.4%. Sounding improved agreement of horizontal measurements to 64.2%, 83.6%, and 88.3%, respectively. Underestimation of surgical furcation depths by pre-anesthesia probing was much more common than overestimation. Sounding reduced the percent and degree of underestimation in all furcation types. The data demonstrate the ability of post-anesthesia bone sounding to significantly improve the diagnostic accuracy of furcation invasions.

Clinical perspectives of periodontal and restorative interactions.

Restorative treatment and periodontal health are directly interrelated. A restorative treatment plan must consider periodontal support and provide for adequate maintenance of the health of the periodontium. For example, prosthetic design must facilitate hygiene practices and not violate the physiologic dimensions of the periodontium. The relation of the periodontium to margin preparation, margin placement, crown contours, and pontic design are discussed in this article.

The clinical effectiveness of open versus closed scaling and root planing on multi-rooted teeth.

Scaling and root planing are the most common techniques utilized to achieve a biologically-acceptable root surface. Thorough root debridement is a demanding task, with residual deposits of plaque and calculus a not uncommon finding after instrumentation. This study evaluated the effectiveness of scaling and root planing via a closed versus an open flap approach. Sixty multi-rooted teeth were assigned to one of three groups: untreated controls, closed scaling/root planing, and open flap scaling/root planing. Following debridement, teeth were extracted, immersed in methylene blue, and examined for the percent surface area having stainable residual deposits. The mean percent stained surface area covered by residual plaque and calculus was 54.3% in the closed root planing group compared to 33.0% in the open flap root planing group. The untreated control teeth had 91.0% of the root surface covered with stainable deposits. Within-group comparisons showed no significant difference in the percent stained residual plaque and calculus in shallow areas of the pocket (< or = 3 mm apical to the gingival margin) compared to deeper areas (> 3 mm subgingival). Examination of furcation regions demonstrated heavy residual stainable deposits for both treatment methods, with no significant differences between techniques. There was no correlation between the time spent in root debridement and the percent residual deposit area. The results demonstrate that hand instrumentation alone is inadequate for thorough debridement of furcations and suggest that new approaches are needed to provide a root surface which is compatible with formation of new periodontal attachment. High frequency ultrasonic instruments, rotary burs, and chemical agents may assist in debridement of such surfaces.(ABSTRACT TRUNCATED AT 250 WORDS)

Closure of oroantral communication using guided tissue regeneration and an absorbable gelatin membrane.

Surgical intervention into the maxillary posterior area can lead to inadvertent communication with the maxillary sinus. Spontaneous healing of 1 to 2 mm openings can occur. However, in patients with larger oroantral communications and those with a history of sinus disease, surgical closure is often indicated. Acute and chronic oroantral fistula and sinusitis can occur as a result of inadequate treatment. The most common causes of complications include inadequate site preparation, flap closure, flap necrosis, infection, and patient non-compliance. A technique for the closure of oroantral communications using guided tissue regeneration is described. This technique utilizes an absorbable gelatin film (membrane), allogenic bone graft material (DFDBA), and non-resorbable expanded polytetrafluoroethylene (ePTFE) membrane. The gelatin membrane prevents displacement of graft material into the antrum and sinus epithelial cell migration, while the ePTFE membrane promotes selective cell population with subsequent regeneration of the osseous wall of the oroantral defect.

Diagnosis and treatment of subpontic osseous hyperplasia. Report of a case.

This report describes a case of subpontic osseous hyperplasia that occurred in the posterior mandible of a healthy 67-year-old woman. The two hard masses, which were removed from beneath a fixed partial denture that was placed 35 years ago and spanned the lower left first premolar and the first and second molars, consisted of normal viable dense cortical bone. Only 30 cases of this phenomenon defined as a slow-growing, benign osseous proliferation occurring on the crest of the alveolar ridge beneath the pontic of a fixed partial denture have been described in the literature. Possible causes, including genetic programming, functional stimulus, and mild chronic irritation are discussed, as well as rationale for treatment of this anomaly.

Occurrence and resolution of focal epithelial hyperplasia in two siblings with leukocyte adhesion deficiency.

Focal epithelial hyperplasia is an uncommon disorder characterized by formation of multiple asymptomatic oral mucosal papular and/or nodular lesions. This article relates the occurrence and clinical course of FEH in 2 adolescent siblings with leukocyte adhesion deficiency. Histological findings are described and insights into potential causes are discussed.

Periodontal manifestations of the heritable Mac-1, LFA-1, deficiency syndrome. Clinical, histopathologic and molecular characteristics.

The clinical, histopathologic and functional consequences of the genetic deficiency of leukocyte Mac-1, LFA-1 and p150,95 were assessed among three affected patients, heterozygotes and unaffected individuals among two generations of a single kindred. Longitudinal assessments of this family afforded the unique opportunity to characterize the natural history of severe periodontal manifestations associated with this disorder. Features uniformly observed among each patient included recurrent, necrotic soft tissue infections, impaired pus formation, delayed wound healing, constant granulocytosis, severe abnormalities of adhesion-dependent granulocyte functions and a profound deficiency (3%-6% of normal) of Mac-1 glycoproteins on granulocyte surfaces. Characteristic features of generalized prepubertal periodontitis including rapidly progressive alveolar bone loss affecting the primary and permanent dentitions (leading to premature tooth loss), recession, clefting and migration in association with intense gingival inflammation were uniformly observed. Biopsies of inflamed periodontal tissues in these individuals demonstrated dense infiltrates of mononuclear leukocytes but a striking absence of extravascular neutrophil granulocytes. Heterozygous family members demonstrated approximately half normal Mac-1 protein expression but no susceptibility to systemic infections and normal, adhesion-dependent leukocyte functions. Prepubescent heterozygotes demonstrated no periodontal manifestations but a 31-year-old heterozygous female exhibited clinical and radiographic features typical of postjuvenile periodontitis. The profound periodontal manifestations recognized in this clinical-pathologic model emphasize the physiologic importance of leukocyte adhesion reactions in defense of the periodontium and further suggest a possible pathologic role for Mac-1 proteins in other forms of early-onset periodontitis.

Flossing clefts. Clinical and histologic observations.

Clinical and histologic observations of 14 marginal tissue clefts associated with improper floss manipulation are presented. Newly acquired lesions were characteristically inflamed, ulcerated and symptomatic while clefts of chronic duration were asymptomatic and un-noticed by the patient. Cleft sites exhibiting varying degrees of epithelialization generally presented apical bifurcations suggesting reinjury by the patient during lateral positional shifts of the floss. The terminology "flossing cleft" is suggested by the authors to describe linear or V-shaped interdental marginal tissue deformities that result from dental floss-induced injury. While these clefts may serve as a potential source of bacteremia during vigorous flossing and associated oral tissue manipulation, in no instances were they determined to constitute a morphologic impediment to effective plaque control efforts.

The severe and moderate phenotypes of heritable Mac-1, LFA-1 deficiency: their quantitative definition and relation to leukocyte dysfunction and clinical features.

An inherited syndrome characterized by recurrent or progressive necrotic soft-tissue infections, diminished pus formation, impaired wound healing, granulocytosis, and/or delayed umbilical cord severance was recognized in four male and four female patients. As shown with subunit-specific monoclonal antibodies in immunofluorescence flow cytometry and 125I immunoprecipitation techniques, in addition to a NaB3H4-galactose oxidase labeling assay, granulocytes, monocytes, or lymphocytes from these individuals had a "moderate" or "severe" deficiency of Mac-1, LFA-1, or p150,95 (or a combination)--three structurally related "adhesive" surface glycoproteins. Two distinct phenotypes were defined on the basis of the quantity of antigen expressed. Three patients with severe deficiency and four patients with moderate deficiency expressed less than 0.3% and 2.5%-31% of normal amounts of these molecules on granulocyte surfaces, respectively. The severity of clinical infectious complications among these patients was directly related to the degree of glycoprotein deficiency. More profound abnormalities of tissue leukocyte mobilization, granulocyte-directed migration, hyperadherence, phagocytosis of iC3b-opsonized particles, and complement- or antibody-dependent cytotoxicity were found in individuals with severe, as compared with moderate, deficiency. It is proposed that in vivo abnormalities of leukocyte mobilization reflect the critical roles of Mac-1 glycoproteins in adhesive events required for endothelial margination and tissue exudation. The recognition of phenotypic variation among patients with Mac-1, LFA-1 deficiency may be important with respect to therapeutic strategies.

Focal epithelial hyperplasia (Heck's disease). A case report.

The occurrence of focal epithelial hyperplasia (Heck's Disease) in a 12-year-old Mexican-American female is presented. Focal epithelial hyperplasia is a relatively unusual and benign disorder characterized generally by multiple asymptomatic nodules, occurring most commonly in younger segments of indigenous populations and ethnic groups. The clinical behavior, histologic appearance and possible etiologic factors of focal epithelial hyperplasia are discussed.