International Journal of Periodontics & Restorative Dentistry, 03/2001

A series of 21 men and 41 women received grafts resulting in mean faciolingual augmentation of 5.1 mm and mean vertical augmentation of 3.9 mm. In most patients, bone was obtained from the iliac crest. At the time of implant placement, the bone at the site was restored anatomically to type B in 50 patients and to type C in 12. The patients received from one to ten posterior implants, which were placed simultaneously with (n = 5) or approximately 6 months after grafting. All of the implants were loaded, with the follow-up ranging from 12 to 96 months (mean 37.3 months). Ceramometal restorations were ultimately used in all patients. Five patients suffered partial graft loss at a total of 21 implants, of which five (24%) failed. The total failure rate for implants placed in patients who received sinus + veneer grafts was 4% (9/222). In patients who received sinus and J grafts, the final implant failure rate was 2%. All implants placed in anteroposterior J grafts and mandibular grafts were successful. Overall, including replacement implants, the failure rate was 7% (23/329). Posterior implants can be placed after graft reconstruction with a success rate similar to that obtained without grafting, thereby improving the function and esthetic outcome.

A field study using five different private periodontal practices was conducted; it compared two microbiologic culture samples simultaneously secured from the same sites within 23 individual patients and submitted for bacterial identification and antibiotic sensitivity testing to two separate laboratories. The results from the two laboratories were often different. In no instance did both laboratories agree on the presence of identical bacterial species. When only bacteria above threshold levels were compared, agreement was found in only nine of 23 cases. When examining antibiotic sensitivity, using 100% kill of all tested pathogens as the ideal, agreement between the two laboratories was poor. The laboratories agreed on the use of amoxicillin 17% of the time, tetracycline 26% of the time, and metronidazole 48% of the time. The use of amoxicillin and metronidazole in combination yielded a 78% agreement when the results of both laboratories were combined. It would appear from the data that the empirical use of amoxicillin-metronidazole combination therapy may be more clinically sound and cost effective than culturing and antibiotic selection based on the results of culture from any single microbiologic testing laboratory.

The purpose of this study was to histologically evaluate four teeth with recession defects that were treated with guided tissue regeneration (GTR). The amount of root coverage obtained ranged from 16.7% to 50.0%. In one of the defects treated, new bone was formed but none of the new bone was coronal to the original gingival margin. Additionally, in this one case new cementum and connective tissue attachment was formed. However, because the new bone, new cementum, and new connective tissue were not coronal to the original gingival margin, this result could not be classified as regeneration. The vast majority of the attachment in this defect was long junctional epithelial attachment in the portion of the recession defect covered by the root-coverage procedure. In the other three defects treated, there was a loss of bone. All of the root coverage obtained was a long junctional epithelial attachment in three of the four defects. The results of this study do not show regeneration in any of the four defects treated.

The present study was designed to compare recombinant human bone morphogenetic protein-2 (rhBMP-2) impregnated on an absorbable collagen sponge (ACS) with particulate cancellous bone and marrow (PCBM) harvested from the iliac crest in an animal model of maxillary sinus floor augmentation. Bilateral sinus floor augmentation procedures were performed in 30 adult Japanese white rabbits. rhBMP-2/ACS or PCBM was grafted to each maxillary sinus. Animals were sacrificed at 2, 4, or 8 weeks after grafting, and bone formation in response to each implant was evaluated histologically and histometrically. Histometric results compared by analysis of variance revealed no statistically significant difference in the bone volume at augmented areas between the two types of implant (P > 0.05). Histologic evaluation documented that the trabeculae with a lamellar structure were embedded in fatty marrow at 8 weeks in both implant sites. These results suggest that sinus floor augmentation with rhBMP-2/ACS or PCBM induces comparable histologic and histometric evidence of bone formation in rabbits.

This article will address the evolution of occlusal disease from childhood and the deciduous dentition forward. It will include the evolution of anterior wear with emphasis on "cross over" of the mandible. Having classified the types and extent of occlusal disease, new evidence will be shown, on the adult dentition with pathognomonic manifestations, of cross-over or bruxed-braced occlusal disease. Its potential effect on restorative dentistry and dental implants will be discussed.

In part I of this article, the evolution of bruxism from childhood was discussed. Further, the different types of anterior tooth wear were reviewed. Specifically, the type of wear noted in bruxed-braced or cross-over position was pointed out. Examples were illustrated to allow the practitioner to recognize the type of parafunction in advance of treatment. This article will continue the discussion of cross over with moderate to extreme examples. Suggestions for treatment are discussed depending on the severity of the problem. Restorative failure and the implications for implant dentistry are noted.

Removal of barrier membranes may complicate second-stage implant surgery, particularly in mandibular areas characterized by a shallow vestibule and minimal amount of keratinized tissue. A new surgical technique that permits implant exposure and membrane removal combined with a plastic procedure to improve soft tissue quality both buccally and lingually is presented. A midcrestal incision preserving the keratinized tissue available on the lingual side is designed. A double-layer flap is elevated, allowing membrane removal. The inner, full-thickness layer is then sutured back into place, thus protecting the regenerated bone and allowing a recipient bed for a free gingival graft. The outer, partial-thickness flap is sutured apically, thus deepening the vestibule. The advantages and technical aspects of the procedure are discussed.

The aim of the present study was to investigate the healing of alveolar ridge defects augmented with cancellous bovine bone mineral. In six partially edentulous patients, bone augmentation was necessary prior to implant placement because of severe alveolar ridge resorption. The defect sites, all located in the maxilla, were filled with Bio-Oss and covered with the resorbable collagen membrane Bio-Gide. Biopsies were obtained from the defect sites 6 to 7 months following grafting and were processed for ground sectioning. The histologic analysis revealed that the Bio-Oss particles occupied 31% of the total biopsy area. An intimate contact between woven bone and Bio-Oss was detected along 37% of the particle surfaces. A mixed type of bone was found; it contained woven bone and parallel-fibered bone, which demonstrates features of remodeling activity. Signs of resorption of the grafting material were observed in the histologic sections, which indicates that the material takes part in the remodeling process. It is suggested that Bio-Oss may be a very suitable material for staged localized ridge augmentation in humans.

It is the aim of this article to present a surgical option to the traditional method of returning lost biologic width where invasion of the junctional and/or connective tissue attachment associated with a tooth has occurred. The alternative to conventional osseous resection involves reshaping the existing tooth surface in combination with conservative removal of the supporting alveolar bone to create the width needed for the restoration to be biologically acceptable. This procedure accomplishes several goals: (1) minimum supporting bone is removed; (2) deleterious root surface anatomy, such as grooves, concavities, and cementoenamel projections, is diminished; (3) a smooth root surface that is more biologically acceptable to soft tissue is created; (4) Class I and II furcation lesions may be decreased or eliminated; and (5) improved gingival contours and space for restorative materials can be created in situations in which close root proximity is present. This article will present a step-by-step approach to using root reshaping as an alternative to traditional crown lengthening.