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C r o s s - a r c h i m p l a n t - s u p p o r t e d f i x e d r e s t o r a t i o n Varying degrees of marginal bone loss are nor- mally seen around dental implants, regardless of all the efforts to eliminate it.21 Maintenance and improvement of periimplant bone, as well as the establishment and maintenance of a soft-tissue barrier around the implant abutment, are prerequisites for long-term esthetic and functional success of an implant-supported res- toration.5 However, during clinical function, some implants may show extensive and some- times continuous bone loss, whose primary cause is not well understood. Previous authors have proposed several factors that may increase marginal bone loss around dental implants, including surgical trauma, biological width establishment, lack of passive fit of the super- structure, implant–abutment microgap and occlusal overload.21, 22 Continuous bone loss with clinical signs of infection, such as bleeding and suppuration, is referred to as periimplantitis, irrespective of the sequence of events.12 Depend- ing on the definition, the prevalence of contin- uous bone loss in long-term studies has been reported to range from 7.7 to 39.7%;12 however, some authors have regarded this as unrealisti- cally high.10 These figures are mainly based on implants with a machined and relatively smooth surface. Today, most implants have some type of surface treatment to promote a stronger bone tissue response, such as blasting, etching, anodic oxidation and combinations of techniques.23, 24 The moderately rough, highly crystalline, and phosphate-enriched titanium oxide surface of the TiUnite implants features an increased tita- nium dioxide layer, a moderately rough micro- structure that enlarges the osseointegrable surface area, and it has been reported to enhance the adhesion of human osteoblastlike MG-63 cells to titanium without significantly affecting the pattern of gene expression.23 Concerns have been raised that bone loss and subsequent expo- sure of a rough implant surface may facilitate establishment of a periimplant infection.24 Though the numbers of longer-term follow-up are small, positive clinical and radiographic per- formance of implants with a porous anodized surface has been reported.18, 24 This contradicts a short-term animal study that stated that the porous anodized surface of TiUnite is more sus- ceptible to progressive periimplant loss once established.25 In the presented case, the patient’s chief desire was to have her hopeless teeth replaced with implant-supported fixed restorations, keeping the remaining teeth. The patient understood and agreed to the treatment plan and was informed about the higher risk of implant failure owing to her periodontal disease. The outcomes of this case depended on patient compliance with the periodontal program. Follow-up and intervention, when indicated, are important in a case with a history of periodontal disease. In particular, the good outcome at site 47 demonstrates the benefit of flap intervention to remove retained cement and, potentially, the added benefit of subgingival antimicrobial deliv- ery to address periimplantitis and recover lost radiographic bone despite prior infection and bone loss. This would suggest that a contami- nated microrough surface does not always lead to progressive bone loss if there is suitable inter- vention. Also in this case, the usage of the brux- ism appliance was critical to reduce potential biological and technical complications. Accord- ing to a recent systematic review, bruxism is unlikely to be a risk factor for biological compli- cations around dental implants, but it is more likely to be a risk factor for technical complica- tions.16 The caution that is urged when using implants to support dental prostheses in bruxers is due to the common fear that bruxism can cause overloading and may affect osseointegra- tion and/or compromise the integrity of techni- cal components and veneering materials. Keep- ing this in mind, care must be exercised in periodic control of occlusal design and presence of nonaxial loads on implant-supported resto- rations, and adequate levels of oral hygiene must be maintained in the long term in order to avoid increasing the risk of periimplant disease. Conclusion Implant treatment in patients exhibiting ongoing active periodontal disease and bruxism is not contraindicated provided that adequate infec- tion control and an individualized maintenance program are assured. The results of this case illustrated good clinical and radiographic out- comes with long-term prosthetic stability. Con- founding factors, such as the minimally rough surface of the implant, did not seem to cause bone loss. Competing interests The authors declare that they have no compet- ing interests. 54 Volume 3 | Issue 3/2017 Journal of Oral Science & Rehabilitation