Background: After local anesthesia, which is frequently used in pediatric dentistry, long-term soft tissue numbness can cause various problems. The aim of this study was to evaluate the effectiveness of PBMT in reversing soft tissue anaesthesia in children following local anaesthesia administration.

Methods: In a split-mouth randomized study, 40 children aged 4 to 9 years, eligible to receive local infiltration injection on both maxillary (n=20) and mandibular (n=20) right and left sides, will included. Maxillary and mandibular quadrants will be randomly assigned to laser or sham laser groups. Normality will assessed using the Kolmogorov-Smirnov test. Categorical variables between laser and control groups will compared using the McNemar paired sample test. Significance will be set at p<0.05.

Inclusion Criteria:

• - Children whose parents signed the written informed consent form and who themselves gave assent,
• Children with a Frankl behaviour rating scale score of 3 or 4,
• Children aged between 4 and 9 years old who can understand soft tissue sensation and respond to it,
• Children requiring treatment with local infiltration anaesthesia for multiple teeth in both the mandible and maxilla,
• Children with no history of allergy to materials used for anaesthesia or sulphite,
• Children who have not taken any analgesic medication at least 24 hours before treatment,
• Children without any systemic conditions that would interfere with dental treatment under local anaesthesia.

Exclusion Criteria:

• Occurrence of an error during anaesthesia injection resulting in insufficient anaesthesia for treatment,
• Inability of the patient to provide clear assessments of response to soft tissue anaesthesia,
• Presence of systemic conditions that would prevent anaesthesia administration or dental treatment,
• Children requiring urgent dental treatment priority such as acute painful teeth.