Three-dimensional technologies for personalized external breast prostheses: a comparative user evaluation after unilateral mastectomy

Background: Commercial external breast prostheses are commonly used after mastectomy, but standardized models may not accommodate individual anatomical characteristics, affecting comfort, stability, and appearance. Three-dimensional technologies enable anatomical personalization; however, technical feasibility does not necessarily ensure a satisfactory user experience. Aims: To compare the experiences of women after unilateral mastectomy using personalized external breast prostheses and their routinely used commercial prostheses. Methods: This exploratory comparative study combined quantitative ratings and qualitative observations. Fourteen women who had undergone unilateral mastectomy without reconstruction completed a preliminary interview about prosthesis use and satisfaction. Five participants reporting neutral or negative overall satisfaction were selected for personalization. Individualized models were developed from three-dimensional scans of the remaining breast and mastectomy region. Three participants completed the final evaluation, wearing each prosthesis for 20 minutes and performing standardized body movements. Comfort, thermal sensation, stability, anatomical accommodation, weight, shape, size, and overall satisfaction were evaluated using five-point Likert-scale questions and qualitative observations. Results: All three participants rated the posterior fit of the personalized prostheses positively but rated their commercial prostheses negatively for this attribute. The weight of the personalized models was also positively evaluated by all participants. Two reported increased overall satisfaction with the personalized prosthesis, whereas one maintained a neutral assessment. No consistent differences were observed in incision discomfort or thermal sensation. Perceptions of external shape and size varied. Qualitative observations identified excessive lateral volume, anterior projection, interference with arm movements, and instability during forward trunk flexion as aspects requiring refinement. Conclusion: Anatomical personalization may improve chest-wall accommodation and user satisfaction. Nevertheless, anatomical correspondence alone does not ensure overall suitability. User evaluation should guide the refinement of external geometry, physical properties, stability, and interaction with the body during movement.