Restorative design and associated risks for peri-implant diseases.

The prevalence of inflammatory conditions around dental implants is significant. Current analysis indicates that the rates for peri-mucositis and peri-implantitis may be as high as 40%-65% and 20%-47%, respectively. Over the last decade, many risk factors have been associated with peri-mucositis and peri-implantitis, creating a multifactorial disease etiology that complicates both diagnosis and treatment. Furthermore, additional considerations such as initial surgical implant placement position, disruption of the biologic interface associated with the implant-abutment interface manipulation, or prosthetic design may also influence the host response to commonly employed oral prostheses or the diagnosis of inflammatory states. Coupled with the temporal nature of disease progression around implants, understanding and accounting for these additional parameters may help reduce the number of variables that the surgeon/restorative team face when incorporating implant therapy into daily practice. Therefore, this review discusses the importance of surgical and restorative design by reviewing the concepts of natural and prosthetic emergence profile and implant design and position, as well as many other restorative concepts related to potential implant complications and disease. Understanding both the inflammatory nature of peri-implant disease and additional parameters related to both surgical and prosthetic procedures may provide the best possible approach to reducing the prevalence of both peri-mucositis and peri-implantitis within the realm of dental implant therapy.

Diagnosis and Clinical Management of Human Papilloma Virus-Related Gingival Squamous Cell Carcinoma in a Patient With Leukemia: A Case Report.

INTRODUCTION: Close clinical inspection for intraoral lesions in patients with leukemia that develop chronic graft-versus-host disease (cGVHD) is critical. Additionally, neoplasias developing in bone marrow transplant patients after treatment for leukemia represent a significant obstacle for long-term patient survival, necessitating lifetime follow-up by health care providers. This case report describes the identification, diagnosis, and treatment of gingival squamous cell carcinoma (SCC) in a patient with leukemia who was treated previously with a stem cell transplant and referred for routine periodontal care. CASE PRESENTATION: A 53-year-old male was referred to the Department of Periodontics for an assessment of tooth #10 with 2+ mobility and associated cross-bite occlusion. The patient was diagnosed with acute myeloid leukemia at age 39 years, received hematopoietic stem cell transplantation (HSCT), and later developed cGVHD followed by human papilloma virus (HPV) infections. During the periodontal evaluation, a large, non-painful, exophytic, alveolar gingival mass was identified and later diagnosed as SCC. It is unusual that oral SCC presents as an exophytic, gingival swelling. The patient received comprehensive periodontal management in coordination with his otolaryngology team before and during the diagnosis of SCC secondary to cGVHD and HPV infection. CONCLUSIONS: Patients with a history of HSCT treatment for leukemia and subsequent cGVHD are at a high risk of developing second primary oral malignancies, including SCC. Exposure to oncogenic HPV infection may compound this risk. Therefore, it is important for dentists to be aware of special treatment concerns and to frequently screen these patients to achieve early diagnosis and treatment of these neoplasms.

Supracrestal Bone Grafting Success With a Novel Application of an Absorbable Space-Maintaining Material.

INTRODUCTION: Developing regenerated ridge form with resorbable materials has been difficult because of a lack of space-maintaining properties of available materials. Further combining the regeneration with the placement of implants to gain supracrestal ridge height can save the patient from additional procedures. This case series reports on the use of a shapeable, space-forming absorbable material in conjunction with implant placement, bone grafting, and allogenic dermal material. To our knowledge, this is the first implant site development application of this type of absorbable space-maintaining material. CASE SERIES: Cases were chosen from a larger group to demonstrate clinical outcomes and minor complication management. Patients with large ridge defects were treated with simultaneous implant placement and supracrestal bone reconstruction. CONCLUSIONS: These cases demonstrate a favorable outcome with a unique material borrowed from cranial reconstruction. With careful surgical technique, this material may be used to gain adequate bone in a defined form, and implant placement may be considered simultaneously.

Accuracy of implant placement using precision surgical guides with varying occlusogingival heights: an in vitro study.

STATEMENT OF PROBLEM: Surgical guides may interfere with effective use of surgical instrumentation during implant placement in the posterior segments where interocclusal distance may be limited. PURPOSE: The purpose of this study was to measure and compare the accuracy of posterior implant placement using 3 precision surgical guides with varying occlusogingival heights, and to evaluate the difference in accuracy of implant placement through precision guides as compared to freehand placement. MATERIAL AND METHODS: Three groups of surgical guides were fabricated with occlusogingival heights of 4, 6, and 8 mm, respectively. A jig was fabricated to allow for accurate positioning in bone substitute blocks. Ninety implants were placed in the mandibular first molar site on a manikin. Thirty implants (Astra Tech AB) were placed for each group, with 15 through the guide and 15 freehand. Distances between a reference implant and each placed implant were measured at both implant and abutment levels using a coordinate measuring machine. Apex position and angular discrepancy were calculated using the coordinates of the centers of the implant platform and of the occlusal aspect of the abutment. Data was assessed using 2-way ANOVA (alpha=.05). RESULTS: Two-way ANOVA demonstrated that guide height did not significantly affect the accuracy of the implant position. The distance from the reference point to the point of measurement was significantly smaller for placement through the guide compared to freehand placement at both implant (P<.001) and abutment levels (P<.001). The angular discrepancy was also significantly smaller for placement through the guide (P<.001). CONCLUSIONS: Precision surgical guides with 4-mm occlusogingival height allow placement as accurate as precision guides with 8-mm height. Placement through the guide reproduced the target position more accurately than freehand insertion.

Histologic comparison of a thermal dual-etched implant surface to machined, TPS, and HA surfaces: bone contact in vivo in rabbits.

PURPOSE: To evaluate the bone contact percentage around a proprietary high-temperature dual-etched (DE) implant surface (Osseotite) versus implants with machined, hydroxyapatite (HA), and titanium plasma-sprayed (TPS) surfaces. MATERIALS AND METHODS: Each implant type was placed in rabbit tibiae of the same animal and assessed at 1 to 8 weeks. Histologic sections were prepared and analyzed histomorphometrically. RESULTS: The DE implant surface achieved higher levels of bone contact percentage than the other surfaces. This enhanced contact level was apparent by 3 weeks and seen at all time intervals except 2 weeks, at which machined exceeded the DE mean. In evaluating which surface outscored the others in each individual rabbit, there was a statistically significant confidence for the DE surface (P < .001). The other 3 surfaces failed to show significance, although the numeric scores for the TPS surfaces were below random expectations and the machined scores were slightly above. There was no correlation between degree of roughness and bone contact percentage. DISCUSSION: Arbitrarily roughening the implant surface may not result in a large change in bone conductivity. The specific texture of the DE process yielded more contact, possibly as the result of better fibrin clot retention and growth factor enhancement. CONCLUSIONS: There was no advantage demonstrated in this model to an HA surface over titanium. The bone contact to the rough HA surface scored similarly to that for the TPS surface of similar roughness, and well below that for the DE titanium surface. The DE surface appeared to have an advantage in bone contact percentage, particularly in early healing in a rabbit tibia model.