International Journal of Periodontics & Restorative Dentistry, 04/1997

There is little support in the dental literature to justify the use of lasers for periodontal root therapy. To the contrary, there are several in vitro studies suggesting potentially adverse effects when lasers are applied to root surfaces. The purpose of this study was to evaluate, in vivo, soft tissue attachment to root surfaces following CO2 laser irradiation. Using a four-quadrant design with one quadrant serving as an untreated control, the remaining quadrants in each of two dogs were treated by (1) scaling and root planing, (2) laser only, and (3) laser followed by scaling and root planing. Prior to the assigned treatments, the roots of three teeth in each quadrant (including the control) were exposed by flap reflection and ostectomy. After root therapy the flaps were repositioned and allowed to heal for 28 days. Clinical attachment levels were determined prior to surgery, at 28 days, and by histologic measurement. Results indicate that specimens treated with laser only lost attachment compared to controls and other treatment groups. Furthermore, there was no histologic evidence of soft tissue attachment to a laser-treated surface that featured a residual char layer.

An index to assess the size of the interproximal gingival papillae adjacent to single implant restorations was described and preliminary tested in a pilot study of retrospective material comprising 25 crowns in 21 patients. The result indicated a significant spontaneous regeneration of papillae (P .001) after a mean follow-up period of 1.5 years. Based on these results, the general conclusion was made that the proposed index allows scientific assessment of soft tissue contour adjacent to single-implant restorations. The results also indicated that soft tissue changed in a systematic manner during the ti me period between insertion of the crowns and follow-up 1 to 3 years later.

Periodontitis resulting from Papillon-Lefevre Syndrome has been known to cause early loss of primary dentition with subsequent involvement of the permanent dentition. In this stu dy, two Papillon-Lefevre Syndrome patients were followed for 3 years after initial treatment and improvement of their periodontal condition. In addition, two new cases of Papillon-Lefevre Syndrome are presented. The follow-up treatment of the first two patients included monitoring the oral hygiene and performing ultrasonic scaling. Their present clinical appearnace is very satisfactory. The periodontal condition of the third (new ) patient was brought under control by extracting the involved deciduous teeth under antibiotic coverage, and by scaling and root planing the already erupted permanent teeth as well as by maintaining a high standard of oral hygiene. In the fourth case, all permanent teeth had erupted and the periodontium had already been severely destroyed. Actinobacillus actinomycetemcomitans was not detected by microbiologic examination after the periodontal conditions improved, except in the fourth case. Western blot analysis showed that the three first three patients had positive antibody response to the same anti gens of Actinobacillus actinomycetemcomitans. Phagocytosis by polymorphonuclear neutrophil leukocytes) had not decreased, but the expression of surface receptors of polymorphonuclear neutrophil leukocytes was within the normal limits.

The elevation of the floor of the maxillary sinus is becoming a routine surgical procedure to develop the site for dental implants. This delicate procedure is best performed with diagnostics of the highest magnitude. To this point, computer tomographic scans provide valuable information, especially when defining the location and extension of septae transversing the sinus. Additional useful information is provided by a replicate resin model that is constructed from a magneto-optical disk compatible with a personal computer. The image data is then converted to a DOS format. Bone structures of interest are thresholded in each slice based on single-pixel gray levels. Object profiles with linear interpolation and their elaboration generate the three-dimensional surface of the object. Finally, the physical resin model is fabricated.

Bioglass particulates were surgically placed in the periodontal osseous defects of 12 patients. The clinical parameters studied were probing depth, attachment level as measured with the Florida Probe, and standardized bitewing radiograph comparisons. Data was collected initially, and at 3-, 6- and 24-month posttreatment intervals. Statistically significant improvements were demonstrated in all clinical parameters studied. There was a mean probing depth reduction of 3.33 mm, a mean attachment gain of 1.92 mm, and a mean radiographic bone fill of 3.47 mm. Results were stable over the 24-month period. Ease of handling and excellent tissue response were characteristic of the material.

The influence of end abutment and cantilever fixed partial dentures on periodontal health was examined in 12 patients with periodontally reduced residual dentition. The prosthetic appliances had been integrated for 4 to 6 years before the first follow-up examination and had no technical defects at baseline. Two follow-up examinations were performed at a 12-month interval to record clinical and microbiologic parameters of 62 abutment teeth, 45 of which were fitted with end abutment fixed partial dentures and 17 with cantilever fixed partial dentures. Both types of fixed partial dentures were represented in all patients. The patients were on a 6 to 8-week recall schedule throughout the study period and had good oral hygiene. At both examinations, subgingival plaque samples were taken at all proximal surfaces and evaluated by dark-field microscopy. The clinical parameters used were Gingival Index, Plaque Index, pocket probing depth, and attachment level. The results showed that both types of fixed partial dentures were compatible with periodontal health subject to optimal oral hygiene. The clinical parameter s recorded remained stable at a very low level throughout the study period and were almost identical in both groups. A slight gain in clinical attachment level, with a mean value of 0.19 mm for abutment teeth fitted with cantilever fixed partial dentures and of 0.32 for end abutment fixed partial dentures, was registered during the study period. The composition of the subgingival plaque showed a microflora reflecting virtually health periodontal conditons. The proportion of motile rods and spirochetes was slightly elevated in both groups. In conclusion, it can be stated that both fixed partial denture t ypes display identical characteristics in the periodontally damaged dentition and do not lead to deteriorati on of the periodontal situation if oral hygiene is closely monitored.

A computer imaging technique has been advocated for measuring the volumetric fill in furcation defects. Histologic material for this investigation was obtained from an animal study using five adult baboons (Papio anubis). The photographed histology was converted into digitized electronic information, and a computer calculated the overall volume of defect fill for the treated and the untreated control sites. All volumetric measurements were expressed as a percentage of the original surgically created defect size, with 100% indicating complete healing of the defect. The results indicate that none of the defects acheived complete healing. Teeth that had received flap debridement had the most overall defect fill (79.50%). Teeth that received a biodegradable barrier (Epi-Guide) showed a mean overall defect fill of 74.98% while sites treated with ane xclusion barrier (Gore-Tex) showed 70.75% overall fill. The untreated control teeth showed a mean overall fill of 78.70%. A variety of statistical tests revealed no significant differences among teeth within the same animal and between treatments and controls. The following conclusions were drawn: (1) digital imaging technology is a useful research tool for determining the volume of defect fill in surgically created grade II molar periodontal furcation defects in the baboon model; and, (2) no significant differences were found among the treatment modalities and the untreated control sites.

The authors have developed a set of four modified sonic scaler inserts with variously shaped shafts and diamond-coated budded inserts. The inserts are specially designed for the furcation area since instruments used hitherto have not been successful in completely preventing slow continuous periodontal breakdown in multirooted teeth. To test their clinical effectiveness, the displacement amplitude of the different sonic scalers was measured under varying load applications. Each scaler insert generated idfferent and characteristic displacement amplitudes from rest position. The conventional insert was continuously dampened under increasing load application, whereas the diamond-coated inserts showed only minor variations of oscillation pattern. In a clinical situation, both insert types should be used, with the least possible application load to maintain effectiveness and minimize removal of hard tissue.