The success of dental implants is highly dependent on integration between the implant and intraoral hard/soft tissue. Initial breakdown of the implant-tissue interface generally begins at the crestal region in successfully osseointegrated endosteal implants, regardless of surgical approaches (submerged or nonsubmerged). Early crestal bone loss is often observed after the first year of function, followed by minimal bone loss (< or =0.2 mm) annually thereafter. Six plausible etiologic factors are hypothesized, including surgical trauma, occlusal overload, peri-implantitis, microgap, biologic width, and implant crest module. It is the purpose of this article to review and discuss each factor Based upon currently available literature, the reformation of biologic width around dental implants, microgap if placed at or below the bone crest, occlusal overload, and implant crest module may be the most likely causes of early implant bone loss. Furthermore, it is important to note that other contributing factors, such as surgical trauma and penimplantitis, may also play a role in the process of early implant bone loss. Future randomized, well-controlled clinical trials comparing the effect of each plausible factor are needed to clarify the causes of early implant bone loss.

Due to lack of the periodontal ligament, osseointegrated implants, unlike natural teeth, react biomechanically in a different fashion to occlusal force. It is therefore believed that dental implants may be more prone to occlusal overloading, which is often regarded as one of the potential causes for peri-implant bone loss and failure of the implant/implant prosthesis. Overloading factors that may negatively influence on implant longevity include large cantilevers, parafunctions, improper occlusal designs, and premature contacts. Hence, it is important to control implant occlusion within physiologic limit and thus provide optimal implant load to ensure a long-term implant success. The purposes of this paper are to discuss the importance of implant occlusion for implant longevity and to provide clinical guidelines of optimal implant occlusion and possible solutions managing complications related to implant occlusion. It must be emphasized that currently there is no evidence-based, implant-specific concept of occlusion. Future studies in this area are needed to clarify the relationship between occlusion and implant success.

The absence of adequate KM or AM in endosseous dental implants, especially in posterior implants, was associated with higher plaque accumulation and gingival inflammation but not with more ABL, regardless of their surface configurations. Randomized controlled clinical trials are needed to confirm the results obtained in this retrospective clinical study.

This paper reviews the current literature concerning the most common periodontal diseases affecting children: chronic gingivitis (or dental plaque-induced gingival diseases) and early onset periodontitis (or aggressive periodontitis), including prepubertal and juvenile periodontitis. In addition, systemic diseases that affect the periodontium and oral lesions commonly found in young children are addressed. The prevalence, diagnostic characteristics, microbiology, host-related factors, and therapeutic management of each of these disease entities are thoroughly discussed.

Guided bone regeneration (GBR) evolved from the concept of guided tissue regeneration (GTR) and has been used for reconstructing sites with bone deficiencies associated with dental implants. For GBR, the use of absorbable collagen membranes has been increasing, but, at present, scientific information on the use of collagen membranes for GBR is limited. This study was aimed to clinically and histomorphometrically compare two collagen membranes, Bio-Gide(R) and BioMend ExtendTM, for the treatment of implant dehiscence defects in eight mongrel dogs. Implant dehiscence defects were surgically created in edentulous ridges, followed by the placement of three endosseous implants bilaterally in the mandible. Each implant dehiscence defect was randomly assigned to one of three treatment groups: (1) control (no membrane), (2) porcine dermis collagen barrier (Bio-Gide) or (3) bovine tendon collagen barrier (BioMend Extend). Dogs were sacrificed at 4 and 16 weeks (four dogs each) after treatment. Histomorphometric analysis included percentage linear bone fill (LF), new bone-to-implant contact (BIC) and area of new bone fill (BF). The results of the study revealed no significant differences among groups for any parameter at 4 weeks. However, at 16 weeks, more LF, BIC, and BF were noted in the membrane-treated groups than controls. BioMend Extend-treated defects demonstrated significantly greater BIC than control (P < 0.05) at this time point. BIC at 16 weeks was significantly greater than 4-week BIC (P < 0.05). Membrane exposure occurred in 9 out of 15 sites examined, resulting in significantly less LF and BIC than the sites without membrane exposure (P < 0.05). The results of this study indicate that: (1) GBR treatment with collagen membranes may significantly enhance bone regeneration, manifested at late stage (16 weeks) of healing; and (2) space maintenance and membrane coverage were the two most important factors affecting GBR using bioabsorbable collagen membranes.