High levels of cholesterol and triglycerides may have a negative effect on the immune system and bone health, leading to lower bone mineral density, an increased risk of osteoporosis, and bone fractures, and could therefore also be related to a significant worsening of peri-implant health. The purpose of the following study was to evaluate whether the altered lipid profile in patients who undergo implant insertion surgery represents a prognostic factor capable of influencing clinical outcomes. This prospective observational study was conducted on 93 subjects; patients were required to have taken blood tests to obtain triglycerides (TG), total cholesterol, low-density lipoprotein (LDL), and high-density lipoprotein (HDL) levels prior to the surgical procedure to classify them according to current American Heart Association guidelines. The outcomes considered were marginal bone loss (MBL) 3 years after implant placement, full-mouth plaque score (FMPS), and full-mouth bleeding score (FMBS) 3 years after surgery. A statistically significant correlation was found between hypertriglyceridemia and MBL as well as between total cholesterol and MBL. There is no statistically significant correlation between the variables analyzed and the secondary outcomes 3 years after implant placement. Peri-implant marginal bone loss may be influenced by hyperlipidemia. However, further studies are needed, with larger samples and more extensive follow-ups, to confirm these results.