At Neo Lab, we approach every problem systematically, following the stages of product development from the idea, conceptualization, detailing, to testing and improvement of the final product. This approach was used to address our client’s issue of All-on-X provisional restorations fracturing under immediate implant loading. The primary role of provisional restorations under immediate implant loading is to stabilize the implant in the bone, enhance the osseointegration process, and restore masticatory, phonetic, and aesthetic functions. Therefore, fractures in provisional restorations during the early stages of treatment can negatively impact the therapy's success, the osseointegration of the implants, and the patient's psychological confidence in the treatment and the clinician. Scientific and professional literature indicates that 40% of provisional restorations experience fractures, although the exact causes remain poorly understood and unproven. 

Figure 1: Fracture in provisional restoration 

There are notable differences in the rigidity of provisional restorations produced by subtractive (milling) and additive technologies, where the latter is significantly more prone to notch effects directly linked to fractures. Since the exact cause is unknown, it was decided to propose reinforcing the provisional restoration as a solution, as this approach addresses a broader range of causes, reducing fracture occurrences regardless of the underlying issue. The solution was based on research by Dr. Holtzclaw ​[1]​, who tested provisional restorations reinforced with braided steel wire. For the initial prototype, or proof of concept, titanium wire welded to temporary abutments was used, over which the provisional restoration was constructed. This solution was applied in 14 cases, with only one restoration showing a crack but no complete fracture, as the inserted wire prevented the crack from propagating across the restoration’s cross-section. Observing deficiencies during testing led to the development of a new prototype and improvements to the solution. The initial step in generating the new prototype involved analyzing the mechanical impact of different titanium wire configurations using the Finite Element Analysis (FEA) method. FEA simulation showed that the wire consistently absorbs the largest share of the load, and in configurations with two wires (V3 and V4), the additional wire acts as insurance against complete fracture. 

Figure 2: FEA analysis of different wire configurations in the provisional restoration 

An upgraded design with grooves to accommodate the wire was developed, eliminating the need for welding and thereby avoiding residual stress in the provisional restoration. This solution ensures controlled insertion and connection of the wire with the restoration, enhancing the overall strength of the provisional restoration, resulting in durability and reliability at low production costs and with a simple manufacturing process.  

Figure 3: Prototype of a provisional restoration reinforced with titanium wire 

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​[1] D. Holtzclaw, “Effects of Reinforcement on the Fracture Rates of Provisional All-On-4 Restorations: A Retrospective Report of 257 Cases Involving 1182 Dental Implants,” The Journal of Implant & Advanced Clinical Dentistry, 2016. 

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