Introduction There is general agreement that a thick zone of the keratinized tissues around implants promotes accurate prosthetic procedures, permits oral hygiene maintenance, resists recession, and enables esthetic blending with surrounding tissues. A new procedure called Choukroun's technique has been suggested, and it consists of a combination of horizontal apical mattress suture with regular suture to increase the keratinized tissue in the mandibular arch during the first stage after implantation. The proposed procedure has not been evaluated yet in a cohort of patients. Therefore, this prospective study aimed to evaluate the impact of Choukroun's technique on the width and thickness of the keratinized gingiva after oral surgery. Materials and methods A one-group prospective cohort study was conducted on patients referred to the Department of Oral and Maxillofacial Surgery at the Dental College of Al-Wataniya Private University who had been referred to undergo dental implant surgery. The inclusion criteria for the study group were as follows patients with mandibular missing teeth, good oral health, good general health, 18-70 years old, at least 1 mm thickness of keratinized gingiva, and at least 1 mm width of the attached gingiva. A total of 14 patients aged 27-67 years were included in the study. After inserting the dental implants, the suturing was accomplished according to Choukroun's method. The width and thickness of the keratinized gingiva were assessed before surgery and at one and two months post-surgery. Repeated measures analysis of variance (ANOVA) was applied to detect significant differences between assessment times. Results The study sample comprised 14 patients, of which four were females (28.6%) and 10 were males (71.4%). Patients' ages ranged from 27 to 67 years, with a mean age of 54.86 ± 11.73 years. The surgical procedure was performed in three different regions the upper posterior teeth with four patients (28.6%), the upper anterior teeth with three patients (21.4%), and the lower posterior teeth with seven patients (50%). The mean gingival width before surgery was 5.78 mm, whereas the mean gingival thickness was 2.82 mm. There was no significant difference between the three evaluation times in the mean gingival width (P=0.222), and there was a significant difference between the three evaluation times in the mean gingival thickness (P<0.001). The mean mean gingival thickness one month after surgery was significantly greater than its mean value before surgery (mean difference 0.749 mm). Additionally, the mean gingival thickness two months after surgery was significantly greater than its mean value before (mean differences 0.636 mm). Conclusions Using horizontal apical mattress sutures (Choukroun's technique) does not provide any advantage in increasing the width of the keratinized gingiva. However, it does lead to an increase in the thickness of keratinized gingiva in the surgical area. Therefore, the use of horizontal apical mattress sutures is recommended.