en Dental implant Dental implant Original article Original article <p style="text-align: justify;"><span style="font-size:14px;"><span style="font-family:Times New Roman;"><b><span style="color:#2e74b5">Background and Aim:</span></b> Keratinized mucosa width (KMW) has an essential role in peri-implant health. This study aimed to evaluate the impact of KMW on marginal bone loss (MBL) around overdenture-supported dental implants.<br> <b><span style="color:#2e74b5">Materials and Methods: </span></b>In this cohort study, completely edentulous patients received an overdenture with implants in the maxilla and mandible. Two implants were placed in the maxilla and mandible. Ball attachments were used. KMW was measured, and gingival biotype was determined. MBL was evaluated on digital parallel radiographs taken at 12 and 24 months after loading. KMW was the predictive factor, and MBL was the outcome of the study. Data were analyzed using SPSS 21 via Pearson&rsquo;s correlation test, independent t-test, and Chi-square test (alpha=0.05).&nbsp;<br> <b><span style="color:#2e74b5">Results: </span></b>Eighty implants in 20 patients were studied. The mean KMW was 2.05&plusmn;0.88 mm. The mean MBL was 1.32&plusmn;0.46 mm at 12 months after loading, and 1.71&plusmn;0.49 mm at 24 months after loading. Analysis of the data demonstrated a correlation between MBL at 12 and 24 months after loading with KMW and dental implant diameter (P<0.001).<span style="font-family:"Verdana",sans-serif"></span><br> <b><span style="color:#2e74b5">Conclusion:</span></b> It appears that narrow KMW may be associated with an increase in MBL in two-implant-supported overdentures. Gingival biotype may play a role in the detrimental effect of narrow keratinized mucosa on MBL.</span></span><br> &nbsp;</p> Alveolar Bone Loss, Dental Implants, Gingiva, Mouth Mucosa 80 85 http://jrdms.dentaliau.ac.ir/browse.php?a_code=A-10-598-6&slc_lang=en&sid=1 Reza Tabrizi tabmed@gmail.com 100319475328460012270 0000000172047746 No Oral and Maxillofacial Surgery Department, School of Dentistry, Shahid Beheshti University of Medical Sciences, Tehran, Iran. Mahsa Safavi mahsaasafavi@yahoo.com 100319475328460012271 0000000251233141 No Private Dentistry Practice, Tehran, Iran. Mohsen MalekiGorji mohsen_malekigorji@yahoo.com 100319475328460012272 0000000187341833 Yes Oral and Maxillofacial Surgery Department, School of Dentistry, Shahid Beheshti University of Medical Sciences, Tehran, Iran. Majid Torabzadeh torabzadeh.majid@gmail.com 100319475328460012273 0000000202124344 No Department of Periodontics, School of Dentistry, Shahid Beheshti University of Medical Sciences, Tehran, Iran.