Polishing-paste-induced silica granuloma of the gingiva

Polishing-paste-induced silica granuloma of the gingiva, an uncommon condition, may mimic various local or systemic pathological entities. A 33-year-old woman and a 42-year-old man were referred for a localised refractory gingival inflammation. Clinical diagnoses included allergy, lichen planus and herpes. Biopsy showed well-demarcated non-caseating granulomas, associating epithelioid and Langhans giant cells. Special bacterial and mycological stains were negative. Systemic examination and laboratory tests ruled out sarcoidosis and Crohn's disease. Polarised light revealed birefringent crystalline foreign material. A diagnosis of silica granuloma was made. Both patients had frequent dental hygiene treatment including polishing with abrasive paste, suggesting an iatrogenic implantation of the foreign bodies. Gingival damage can result from the use of some dental materials containing silica. Often asymptomatic, sometimes producing visible lesions, granulomatous gingivitis may mislead into wrong diagnosis and treatment. Old silica granulomas may become symptomatic if the patient contracts sarcoidosis.

Muco-gingival and periodontal health recovery following reimplantation of teeth

Reimplantation of avulsed permanent teeth following traumatic injuries is a widely accepted therapeutic measure; however, though periodontal healing is considered to be the major determinant of long-term survival of reimplanted teeth, the mucogingival reaction to reimplantation has never been assessed. In the present study, hygiene level and gingival inflammation of 13 reimplanted teeth were assessed according to the plaque index (PI) and the gingival index (GI) around both reimplanted and control teeth. The periodontal condition was evaluated by measuring probing depth and probing attachment level at the same location. The clinical parameters of the reimplanted teeth were compared with those of contralateral teeth with the help of the non-parametric Wilcoxon signed ranks test. There were no statistically significant differences in PI and GI scores at any points of measurements around both reimplanted and control teeth; neither did probing depths and probing attachment levels differ between reimplanted and contralateral teeth. The results of the present study indicated that the muco-gingival reaction following traumatic avulsion did not affect the long-term prognosis of the reimplanted teeth.

A longitudinal study of various crevicular fluid components as markers of periodontal disease activity

In order to examine the relationship of possible crevicular biochemical parameters to attachment loss (ALOSS), 330 sites from 8 untreated adult patients were monitored longitudinally at 3-month intervals, for up to 1 year. Attachment levels were measured with a force-sensing probe and an acrylic stent in duplicates at each study point. Crevicular samples were collected and used for the determination of the following 11 markers: number of polymorphonuclear leukocytes (PMNs), prostaglandin E2 (PGE2), osteocalcin (OC), alkaline phosphatase (ALP), collagenase (COL), beta-glucuronidase (BG), antigenic and functional elastase (AEL and FEL), alpha-1 antitrypsin (a1AT), alpha-2 macroglobulin (a2M) and aspartate aminotransferase (AST). 10 sites with ALOSS of > or = 1.5 mm per 3 months (active sites) and 43 sites with negligible changes (inactive sites) were identified. Total amounts of ALP, BG and COL were found to be significantly higher in active as compared to inactive sites, prior to significant ALOSS, without any significant differences in crevicular fluid volume and clinical indices. When biochemical parameters were expressed as ratios to the number of PMNs, PGE2/ PMNs was significantly elevated in active sites. The capacity of such individual parameters to distinguish between active and inactive sites was limited. However, linear discriminant analysis using total amounts of PGE2, COL, ALP, a2M, OC and AEL showed more significant diagnostic values (sensitivity: 80%, specificity: 91%). These findings suggest that the combination of several biochemical parameters in crevicular fluid could give more information to predict future clinical ALOSS.

Bone density of class II furcation lesions treated by guided tissue regeneration. A follow-up study by digital analysis of superimposable radiographs

12 buccal or lingual class II furcation lesions were selected in the lower molars of 7 patients after treatment by routine scaling. In each of the 7 patients, 1 lesion was treated by guided tissue regeneration (GTR) with expanded polytetrafluoroethylene membranes, while 5 neighbouring molars underwent conventional flap operations. The index of gingival inflammation, the plaque index, the depths of the pockets, the horizontal and vertical attachment levels were measured before and 6 months, 1 year and 2 years after surgery. Standardized reproducible radiographs were taken before treatment, post-operatively (at the time of membrane removal for the GTR treated sites), at 6 months, 1 year and 2 years after treatment. The density of bone was quantified in several areas by using high-resolution digital analysis. With the exception of the higher gain in horizontal attachment observed in the GTR treated furcations, the improvement of clinical parameters was similar in all sites during the 2 years of follow-up. The radiographical analysis showed no statistically significant changes neither in the GTR nor in the conventionally treated lesions over this period of time, even when they were compared to untreated bone control areas. However, in this study limited to 7 patients, the interdental bone next to the GTR treated furcations showed significant signs of remodeling.

A case of localized juvenile periodontitis: treatment and 3 years follow-up with superimposable radiographs

A 17-year-old male patient with localized juvenile periodontitis was treated by subgingival instrumentation with full thickness flap on the lower molars, combined with a 3-week course of systemic tetracycline, and a programme of supervised oral hygiene. The treatment was rapidly followed by dramatic clinical and microbiological improvement. However, despite good oral hygiene, gingival inflammation recurred at regular intervals. It was necessary to maintain the clinical results by periodic subgingival instrumentation with an ultrasonic scaler. Healing of alveolar bone was monitored in the lower 1st molar regions over 3 years by using superimposable radiographs. Quantitative analysis of bone density performed with a high-resolution digitalisation technique showed a considerable improvement 1 year after therapy. However, continuous remodelling, probably related to variations in inflammation, occurred during the 3 postoperative years.

Reliability of a paralleling instrument for dental radiographs

The reliability of a paralleling instrument for dental radiographs was retrospectively evaluated in the course of a 6-month clinical study. The angular variation between successive exposures was precisely quantified. Ninety-one percent of the angular variations were below a 1.4 degree threshold, but some paired images were found unsuitable for quantitative analysis. A mathematic procedure to assess the global angular projection error of any similar coupled x-ray cone-film holder device is proposed. This mathematic procedure should be routinely used to check superimposability of serial radiographs before density quantification or subtraction.

Comparison of photodensitometric with high-resolution digital analysis of bone density from serial dental radiographs

Photodensitometry is known to provide high spatial resolution and continuous measurement of optical density for the analysis of dental radiographs, whereas digitization allows powerful image manipulations but, when using conventional video cameras, gives less spatial resolution and fewer grey levels. The aim of this study was therefore to develop a technique of high-resolution digital analysis for the measurement of bone density following the same principles as those of photodensitometry and based upon the use of a CCD Scanner Camera which provides up to 4096 grey levels and a spatial resolution of 4096 x 4096 pixels. Twenty-four zones were analysed with both techniques in five serial dental radiographs taken before and after periodontal therapy in eight patients. Statistical comparison of the results obtained by digital analysis and photodensitometry shows that the two techniques have the same accuracy.

Increase of interproximal bone density after subgingival instrumentation: a quantitative radiographical study

Ten interproximal sites, with periodontal pockets deeper than 5 mm and showing loss of bone on standard dental radiographs, were treated by subgingival instrumentation in 10 patients properly motivated and given thorough hygiene instructions. The index of gingival inflammation, the plaque index, the degree of mobility, the depth of the pockets, and the loss of attachment were measured before starting the treatment, and 2 months, 6 months, and 1 year after treatment. Standardized reproducible radiographs of the 10 sites were taken by using a recently developed paralleling instrument before treatment, immediately after and 2 months, 6 months, and 1 year afterwards. The density of the interdental bone was measured on the radiographs by a computer assisted densitometric technique at three levels of the interdental septum: the most occlusal or "superficial" level; the "deep" level, arbitrarily chosen 1.5 mm below; and the "control" level, in a much deeper area of interproximal bone. As further control, the density of the superficial crestal bone was also followed in 5 healthy untreated sites from 5 of the patients. As expected, a significant improvement of the clinical parameters was observed during the year following therapy. The results of the radiographical analysis showed statistically significant increases of both the superficial and deep average densities of interproximal bone at 6 months and 1 year after treatment. The superficial bone density was, on the average, 13% higher at 6 months and 16% higher at 1 year, as compared to that measured immediately after treatment.(ABSTRACT TRUNCATED AT 250 WORDS)