International Journal of Periodontics & Restorative Dentistry, 05/2000

The present study evaluated the clinical performance of bonded porcelain veneers (PV) restoring substantial coronal volume and length in the anterior dentition. Forty-eight PVs were placed in 16 patients, with systematic coverage and reconstitution of the incisal edge, including well-defined anterior guidance. A standardized protocol comprising diagnostic steps that integrate additive waxups and acrylic mockups was used. PVs were fabricated using feldspathic and low-fusing porcelains in a refractory die technique. Incisal overlaps featured freestanding porcelain spans ranging from 1.5 to 5.5 mm. After a mean clinical service of 4.5 years, 13 clinical parameters for each tooth and 4 parameters that applied to persons were recorded. Permutation tests evaluated the effects of margin location, incisal edge span of porcelain, overbite, opposing contact location, and restoration age on ceramic failure and clinical marginal adaptation and seal. At recall, 100% of the veneers were satisfactory with minor interventions. The effect of slight marginal defects and porcelain cracking was negligible. Biologic, periodontal, and esthetic parameters showed excellent results, which were supported by 100% patient-reported satisfaction. All patients felt comfortable with the newly defined anterior guidance. Aging was negligible, and there were no significant effects of margin location (P > 0.08), incisal edge span of the ceramic, or overbite (P > 0.22) on ceramic failure and marginal performance. Minor alterations of the palatal margin, however, tended to be more frequent compared to facial locations, and were found especially when the opposing tooth contact in centric occlusion was located on the palatal margin (P = 0.028). Bonded ceramic restorations represent a reliable, effective procedure to restore extensive coronal volume and length in the anterior dentition.

This study examined the healing of intrabony defects around 5 teeth treated with bioactive glass ceramic (PerioGlas). Healing was evaluated by clinical measurements, radiographic observation, and histologic analysis. The protocol included a presurgical phase of scaling and root planing therapy, with measurements obtained immediately prior to the surgical procedures and after 6 months of healing. Following therapy there was a mean of 2.7 mm of probing depth reduction, 2.2 mm of clinical attachment gain, and 0.5 mm of recession. The histologic analysis revealed healing by a long junctional epithelium with minimal new connective tissue attachment to the teeth, except in one case where the intrabony region demonstrated new cementum formation and new connective tissue attachment. Graft particles were found to be biocompatible, as evidenced by being embedded in a stroma of dense connective tissue with minimal inflammatory infiltrate. There was minimal new bone formation limited to the most apical borders of the defects. No signs of periodontal regeneration as defined by new cementum, periodontal ligament, and bone formation on a previously diseased root surface were observed. Although the clinical results are encouraging and radiographs evidenced radiopacities within the defects, histologic analysis revealed that as a periodontal grafting material, bioactive glass ceramic has only limited regenerative properties.

In periodontitis lesions with interproximal craters, periodontal flap surgery with osseous recontouring allows more apical positioning of the soft periodontal tissue than flap surgery without osseous recontouring. The present study determined the clinical and microbiologic responses to periodontal surgery with and without osseous recontouring in adult periodontitis lesions with interproximal craters. In 7 osseous surgery patients, osteoplasty and ostectomy were performed from the lingual/palatal aspect to eliminate interproximal osseous defects and to partly mimic the original alveolar bony transition to neighboring teeth. In 7 nonosseous surgery patients, the surgical flap was adapted to the preexisting osseous level. Clinical monitoring included periodontal probing depth, Plaque Index, gingival bleeding index, and radiographic examination. Samples of the subgingival microbiota were examined. In sites treated with osseous surgery, mean pocket depth was 5.5 mm at baseline, 1.9 mm at 1 month, 2.0 mm at 3 months, and 2.1 mm at 6 months. In sites not receiving osseous recontouring surgery, the corresponding pocket depths were 5.9 mm, 3.1 mm, 3.8 mm, and 4.1 mm. At baseline in the osseous surgery group, Actinobacillus actinomycetemcomitans was recovered from one patient and Porphyromonas gingivalis from 5 patients; posttreatment, these microbiota were not detected in any patient. In the nonosseous surgery group, the presence of A actinomycetemcomitans increased posttreatment, and levels of P gingivalis remained essentially unchanged after therapy. This study suggests that in patients not receiving adjunctive antibiotic therapy, apically positioned flap surgery with osseous recontouring is more effective than apically positioned flap surgery without osseous recontouring in reducing periodontal pocket depth and levels of major periodontal pathogens.

This article describes the use of short, porous-surfaced root-form dental implants and an indirect, simultaneous, osteotome-mediated sinus elevation procedure to restore the posterior maxilla when as little as 3 mm of bone remain below the sinus floor. Results with 16 patients who are part of an ongoing prospective clinical trial using the Endopore implant show 100% success (using established criteria) with a mean implant length of 6.9 mm and a mean functional time of 11.1 months. This treatment approach greatly simplifies the management of the posterior maxilla with minimal bone height below the sinus floor.

The role of polypeptide growth factors in periodontal regeneration has been documented through animal and human studies. Human platelets contain platelet-derived growth factor (PDGF) and transforming growth factor-beta (TGF-beta) in their alpha granules. PDGF has been shown to play a role in periodontal regeneration. It has been demonstrated that TGF-beta has a very potent effect on cells associated with bone. The case reports presented demonstrate a new biotechnology in which platelet gel is used in combination with demineralized freeze-dried bone allografts for the treatment of periodontal osseous defects. The treated teeth presented with severe bone loss and a guarded prognosis. Platelet gel biotechnology was used as a novel treatment modality. A significant reduction in probing depths was noted, and radiographically significant amounts of new bone were visible as early as 2 months postoperative. Results up to 2 years postoperative are presented.

This study evaluated the long-term clinical performance of a new resin composite restorative system with a 4-META dentin-bonding agent to seal complete crown preparations prior to temporization and after permanent luting with a companion resin cement. Complete-coverage crown preparations were completed on 33 vital teeth and 5 nonvital teeth (control). The new restorative material demonstrated satisfactory clinical performance for the 3-year test period. The dentin-bonding agent and its companion resin cement successfully eliminated postoperative hypersensitivity in 100% of the prepared vital teeth over the 3-year term, suggesting excellent seal of dentinal tubules exposed by the complete-crown preparations.

There are many possible goals and outcomes of periodontal surgical therapy, but the ultimate goal is regeneration. Since the definition of periodontal regeneration is histologic, it is difficult to document. The purpose of this study was to evaluate a technique that combined a bone graft and guided tissue regeneration (GTR) to see if regeneration occurred. Four teeth with dehiscence-type osseous defects that were scheduled for extraction were treated with bone grafts and GTR. During the surgical procedure, a notch was placed into the root at the apical extent of the calculus. The teeth were extracted with conservative block sections 7 months after the treatment. They were processed, sectioned, stained, and evaluated histologically. The results revealed that regeneration did not occur in any of the teeth treated. In 2 of the teeth new connective tissue attachment was formed. In these 2 teeth cementum could be seen in the notch with connective tissue fibers inserting into the cementum. In one of the teeth the junctional epithelium extended apical to the notch, while in 3 cases the epithelium stopped at or coronal to the notch. In this case report, no regeneration could be documented, but new attachment could be seen in 2 of the 4 teeth treated.

This study presents the histologic analysis of an implant retrieved 14 months after loading because of a fracture in the collar region. The implant (Biovent) was removed with part of the periimplant tissues, and the block was prepared using cutting and grinding equipment to obtain 3 sections approximately 30 µm thick. The examination evidenced a high degree of osseointegration, with a bone-to-implant contact of 74% ± 13%. The lamellar bone was dense and in close relation with the hydroxyapatite coating of the implant. The connection between the 0.4-mm hydroxyapatite coating and the metal was always very tight. The thickness of the metal at the break point was assessed to be 1.6 mm. Besides the relative weakness of the metal at the neck of the implant, other possible causes of failure are discussed.