Group 1 (n=26): Participants in the intervention group will receive two melatonin patches (each containing 1mg of melatonin, AVEELA, USA) attached to the skin of their forearm 30 minutes prior to their dental appointment according to the manufacturer's instructions. Pulse rate, blood pressure, and modified child dental anxiety scale will be measured prior to patch placement, 30minutes after their placement, after local anesthesia injection, and after completion of invasive dental treatment.

Group 2 (n=26): The control group will receive two placebo stickers attached to the skin of their forearm at the same time point (30 minutes prior to the appointment). Pulse rate, blood pressure, and modified child dental anxiety scale will be measured prior to patch placement, 30minutes after their placement, after local anesthesia injection, and after completion of invasive dental treatment.

Group 1 (n=26): Participants in the intervention group will receive two melatonin patches on their forearm (each containing 1mg of melatonin, AVEELA, USA) attached to the skin of their forearm 30 minutes prior to their invasive dental treatment. Pulse Rate, Blood Pressure, and Modified Child Dental Anxiety Scale will be measured before melatonin patches application, after 30minutes of patches application, then after local anesthesia injection, and finally after completing the invasive dental treatment.

The child's anxiety will be measured using the five faces version of the modified child dental anxiety scale (MCDAS). It contains five-point Likert scale each corresponding to a smiley face that describe one of the feelings ranging from "relaxed/not worried" (1) to "very worried" (5). This will be recorded at baseline (pre-intervention), 30 minutes after melatonin patch placement (peri-operatively phase I), then immediately after local anesthesia injection (peri-operatively phase II), and immediately post-operatively.

Measuring patients' systolic and diastolic blood pressure using a digital blood pressure scale. This will be recorded at baseline (pre-intervention), 30 minutes after melatonin patch placement (peri-operatively phase I), then immediately after local anesthesia injection (peri-operatively phase II), and immediately post-operatively.

Measuring patients' pulse rate using digital pulse oximeter scale. This will be recorded at baseline (pre-intervention), 30 minutes after melatonin patch placement (peri-operatively phase I), then immediately after local anesthesia injection (peri-operatively phase II), and immediately post-operatively.

Measuring patients' oxygen saturation using digital pulse oximeter scale. This will be recorded at baseline (pre-intervention), 30 minutes after melatonin patch placement (peri-operatively phase I), then immediately after local anesthesia injection (peri-operatively phase II), and immediately post-operatively.