To observe the application effects of simultaneous dental implant treatment with alveolar process expansion combined with guided bone regeneration (GBR) grafting on patients with severely deficient bone width. Methods The case data of 123 patients with severely deficient from 2016.10 to 2020.10 at Chuzhou Traditional Chinese Medicine Hospital Affiliated to Anhui University.Among them, 66 cases underwent simultaneous dental implant treatment with alveolar process expansion combined with GBR bone grafting and were included in observation group, and 57 cases underwent simultaneous dental implant treatment with traditional alveolar bone dissection and were included in control group.The postoperative bone healing time, bone resorption around the implant (proximal resorption, distal resorption) before surgery and at 1 year after surgery, incidence rates of complications within 1 year after surgery and patient's subjective feelings scores (retention function, masticatory function, aesthetics, comfort) were compared between the two groups.Results The postoperative bone healing time in observation group was shorter than that in control group (P＜0.05).At 1 year after surgery, the proximal resorption and distal resorption of alveolar bone around the implant in the two groups were decreased compared with those before surgery, and the two indicators in observation group were lower than those in control group (P＜0.05).The total incidence rate of complications in observation group within 1 year after surgery was lower than that in control group (P＜0.05).At 1 year after surgery, the subjective feelings scores of retention function, masticatory function, aesthetics and comfort in observation group were higher than those in control group (P＜0.05).Conclusion Alveolar process expansion combined with GBR bone grafting has an exact efficacy, few complications and good postoperative subjective feelings of retention function, masticatory function and aesthetic comfort in the treatment of patients with severely deficient bone width