There are limited long-term treatment results for patients who receive full-mouth laser-assisted new attachment procedure (LANAP). The present study examined cases of full-mouth LANAP therapy for tooth retention, including clinical and radiographic changes. Sixty-six generalized stage III/IV periodontitis patients aged 30 to 76 years were identified via consecutive retrospective chart reviews in a private practice limited to periodontics. Following treatment with the LANAP protocol, differences between baseline and the patient's most recent periodontal maintenance visit (mean: 6.7 years) were determined regarding interproximal probing depths (iPD) and interproximal bone loss (iBL) percentages. Factors affecting tooth loss were analyzed using Cox proportional hazard regression survival analysis. The average tooth loss for the study population was 0.11 teeth/patient/year. Premolars were more likely to be retained compared to the reference group of incisors (hazard ratio = 0.38; 95% CI = 0.16 to 0.90; P = .03), adjusting for canines, molars, and other potential confounding factors. Age at the time of LANAP treatment, gender, history of diabetes, and baseline iBL and iPD were all significantly associated with tooth loss after full-mouth LANAP treatment. Clinical changes in iPD were more significant among premolars and molars when followed up for a period of less than 7 years. Tooth retention after full-mouth LANAP treatment was favorable in this cohort of private practice patients. Int J Periodontics Restorative Dent 2023;43:181-191. doi: 10.11607/prd.6418.