The limited ability to screen prions within the animal genome, along with a long latency period to manifestation of the disease (1 to over 50 years) in infected patients, provides a framework for discussing posible long-term risks of the xenografts that are used so extensively in dentistry. We suggest abolishing the use of bovine bone.

The frequency of dental implant related surgeries that involve soft tissue and bone augmentation procedures has increased significantly. Bovine-derived substitutes have been by far the most commonly used xenografts in dentistry. Albeit literature is replete with clinical studies in favor of bovine-derived graft materials, bibliographical data reporting on risks and clinical complications is scarce. Clinical impression and concern for patient safety led to the report we have provided. The aim of the present case series was to raise awareness on the long-term risks and late clinical complications of bovine-derived graft materials. Patients were referred to a private practice due to bone augmentation complications. Demographics, significant medical and dental findings are reported. Complications included sinus and maxillary bone pathoses, displacement of the graft materials, oroantral communications, implant failure, foreign body reactions, encapsulation, chronic inflammation, soft tissue fenestrations and associated cysts. Bovine-derived graft materials were not biodegradable. Resolution of the associated lesions and symptoms was achieved after the removal of the bone graft materials. The surgical removal of the xenograft materials may require advanced clinical skills because of the different configurations clinicians might encounter of the non-resorbed and migrated particles. The authors’ concern is that patient morbidity may not be reduced with xenografts, due to the inherent risks and associated complications. Clinicians seeking to provide functional and esthetic outcomes should be aware of the complications of the bovine-derived graft materials. The long-term safety of xenografts and their potential association with disease are valid concerns.

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Objective Limited clinical evidence has been reported in dental literature regarding zirconia dental implants. The aim of the present retrospective consecutive case series was to evaluate the clinical outcome of zirconia dental implants with 1 to 5 years of follow‐up. Clinical considerations The clinical outcome of 24 implants in 12 consecutive patients (male 5, female 7) with a mean age of 55 years (range 27‐86) is reported. Radiographic crestal bone level was assessed by the use of “ImageJ” software program. Gingival and plaque indices were recorded at baseline and latest follow‐up. Conclusion The overall success rate of zirconia implants was 92%. Within the limitations of the present clinical evaluation, zirconia implants provided excellent clinical results and esthetic outcomes. A mean periimplant bone loss of 0.3 mm was measured in 33.3% of the implants and 66.7% were not affected by radiographic detectable periimplant bone loss. Two implants in two patients failed. Low gingival and plaque indices were predominant values for both interim and final restorations. The apparent less affinity to plaque accumulation may favor soft tissue health around zirconia dental implants and decrease the risk of inflammation or infection. Zirconia dental implant merits further investigation. Clinical significance Zirconia dental implants are emerging as an option in clinical practice of implant dentistry providing stable clinical results and esthetic outcomes.

The evolution of teeth and maxillary/mandibular bones has distinctively differed in origins and development contributing to tooth impaction and overcrowding. This study demonstrated that closed flap surgery is a reliable procedure for the treatment of impacted teeth that provides periodontal health and esthetic appearance post-orthodontic treatment.