Clinical and Radiographic Evaluation of Local Melatonin Application on Osseointegration of Immediate Mandibular Implants

Dental implant is a treatment option that offers great functional and biologic advantages alongside noticeable long-term success outcomes with survival rates exceeding 95% . Delayed implant placement has been widely and successfully used for replacing missing teeth However, there are some challenges faced with delayed implant placement protocol due to the postextraction alveolar ridge resorption in buccolingual and apicocoronal directions .

The percentage of the post-extraction horizontal and vertical dimensional changes are 29-63% and 11-22% respectively . This is attributed to the disruption of vascular supply due to damage of periodontal ligament leading to pronounced bundle bone resorption . This pronounced post-extraction bone resorption usually leads to functional challenges and the need for augmentation procedures . In order to avoid such challenges, immediate post-extraction implant placement concept was introduced to avoid the bone resorption following tooth extraction and to reduce treatment time . Immediate implant placement showed a high overall implant placement rate reaching 97.1% as reported in the systematic review and 94.9% in the meta-analysis

Although immediate implant placement is effective in preservation of the alveolar bone dimensions but it fails to completely prevent the postextraction dimensional changes . Therefore, attempts were done regarding placement of various biomaterials in the peri-implant gap to increase the immediate implant stability and to minimize or even prevent the post-extraction bone dimensional changes if possible. Multiple materials were successfully used such as bone grafting materials like xenografts , autogenous graftsin addition to the application of bone morphogenetic proteins (BMPs), platelet rich fibrin (PRF) .

Melatonin (MLT) among these agents which are of a great interest for the recent researches whether in the medical or dental fields due to their confirmed physiological and structural functions, their biocompatibility and non-antigenic properties .

MLT is a natural hormone with powerful antioxidant properties, released mainly the pineal gland . It is successfully used in various conditions as sleep disorders, cardiovascular, chronic inflammatory diseases and parkinsonism

Inclusion criteria

• Patients aged between 21 and 60 years.
• Good general health (ASA I).
• Non-smokers or light smokers (<10 cigarettes/day).
• Presence of a single non-restorable mandibular tooth indicated for extraction (incisor, canine, or premolar).
• Adequate bone volume to receive a dental implant.
• Patients with good oral hygiene.

Exclusion criteria

• Medically compromised patients (e.g., uncontrolled diabetes, immunosuppressive therapy, bisphosphonate use)
• Pregnant and lactating women.
• Active periodontal disease at the implant site.
• Acute infection at the extraction site (abscess or sinus tract).
• Severe parafunctional habits (e.g., bruxism, clenching).