Case report on immediate replacement for maxillary posterior teeth with fixed implant-borne restorations: need – opportunity – feasibility of avoiding conventional sinus floor elevation

Background. Development of present implant-borne prosthetic rehabilitation approaches focused on the possibility to obtain the most patient-centered outcomes considering not only functional and esthetic criteria, but also time- and cost-beneficial results. Objective. To represent potential for simultaneous usage of multiple adaptive treatment modalities, including transcrestal sinus floor elevation, angled implant positioning, implant placement within the pterygoid process and intraoral welding, in case of immediate replacement of maxillary posterior teeth with implant-borne fixed restorations. Case report. 50-year-old male patient referred to dental clinic complaining on bilateral aedentia within the distal regions of maxilla and signs of excessive tooth wear in the projection of frontal mandibular teeth. Intraoral scanning procedure helped to agree plan of proposed complex dental rehabilitation with the patient, and later intraoral scanning results were coupled with CBCT data to plan surgical stage of future interventions through specialized software. During the planning stage implant scan bodies were uploaded from the virtual library and positioned on the virtual model following obtained digital treatment plan. Such approach helped to initiate provisional dentures manufacturing within dental lab even before any surgical intervention was provided. Provisional implant-borne dentures were reinforced with the partial titanium bars disconnected from each other in the area of the pontics during modelling stage, but connected later within oral cavity by welding procedure. Considering the need for realization of immediate implant loading protocol to decrease overall treatment duration, it was decided to position needed number of implants avoiding sinus floor elevation through lateral window approach. Taking this into account dental implant in the projection of tooth 1.5 was positioned in adaptive angled positions following sinus wall projection. The lack of space within the left maxillary region did not allow us to choose the same treatment tactics in this area, so it was decided to place the implant in area of missing tooth 2.5, while providing transcrestal sinus floor elevation position before. Placement of dental implant in the projection of tooth 2.7 was provided into the pterygoid process of the sphenoid bone, considering the need in achievement of corresponding primary stability for the immediate loading approach. All implant were placed by using surgical guides manufactured with 3D printing technology within dental clinic conditions. Conclusion. Need for avoidance of conventional sinus floor elevation procedure through lateral window access may be interpreted as prerequisite condition for the realization of immediate implant loading protocol in cases of bilateral aedentia at the distal regions of maxilla. Digital planning expands possibilities for effective complex dental rehabilitation and supports reduction of overall treatment duration, nevertheless, such requires sufficient knowledge and experience for correct performance within intricated clinical conditions. Ethical aspects Authors confirm that they have followed all relevant ethical norms and requirements during the treatment described within present case report and preparation of present manuscript. Authors obtained full patient’s agreement regarding publication of following case report, and such was approved by corresponding consent form signed by the patient personally. No information in present case report may disclose any personal data about the patient, which further may be used for patient’s personal identification. Any information related to patient’s identity disclosure was either deleted or anonymized within present case report. Authors confirm that they have followed CARE guidelines while preparing present case report with intention for further publication. Conflict of Interest Author does not have any potential conflict of interests that may influence the decision to publish this article. Funding No funding was received to assist in preparation and conduction of this research, as well as in composition of this article.