Bone graft added to the dental socket immediately after tooth extraction prevents atrophy and deformity of the bone at the site of element loss, enabling rehabilitation with implants. Photobiomodulation accelerates bone healing; stimulates blood flow; activates osteoblasts, decreases osteoclastic activity, and improves the integration of the biomaterial with bone tissue. The study aims to develop a protocol for the management and preservation of alveolar bone after the loss of first and/or second permanent molars in patients aged between 8 and 17 years, with an indication for extraction associated or not with 808 nm infrared laser treatment. . Materials and methods: 60 patients aged between 8 and 17 years will be randomized and randomly divided into 4 groups, n= 15: Exo (extraction), Exo+Laser (extraction and laser treatment), Exo+Biomat (extraction with graft biomaterial), Exo+Biomat+Laser (biomaterial extraction and grafting and laser treatment). The biomaterials of choice will be Plenum® OSShp and Plenum® Guide (Brazil), added to the alveolus immediately after molar extraction, groups that will receive the laser (λ = 808 nm, power = 100 mW, radiant energy 3J per point in 3 buccal, occlusal and lingual/palatal points), will receive the irradiation in the surgical act, 48 hours and 10 days after the surgery, in the Exo and Exo+Biomat groups a similar laser device without emission of irradiation will be used, the operator who will apply the laser and the patient will be blind to the device used and the patient will not know whether or not he received the biomaterial. Analysis: computed tomography and intraoral scanning were performed pre-surgery, 3 and 6 months after surgery; to assess bone volume by measuring the height and width of the socket in each group, as well as trabecular bone and the interdental space of the teeth lateral to the missing element. Statistical analysis will be performed using the Shapiro-Wilks test, Student's t-test, or Wilcoxon-Mann-Whitney test for parametric and non-parametric data, respectively, they will be two-tailed and the significance level adopted will be α = 0.05.

Clinical, randomized, triple-blind, triple-blind study (the patient will not know whether or not he has received the laser treatment or grafted with the biomaterial, and the operator who will apply the laser will also be blinded to the device with or without laser irradiation.

60 participants will be recruited to attend the dentistry clinic of Universidade Nove de Julho, in the courses of surgery, endodontics, and pediatric dentistry, as well as in a private office, with an indication for the removal of first and second upper and lower molars. This recruitment will only take place after approval by the ethics committee.

4.3 Sample size: The sample size was determined based on the primary outcome of the study: alveolar preservation with scaffold biomaterial. Based on data from Rosero et al. (Photobiomodulation as adjuvant therapy for alveolar preservation: a preliminary study in humans) and Araújo et al. (Ridge changes after engraftment of fresh extraction sockets in man. A randomized clinical trial) Our initial sample size estimate was 9 subjects per group for a significant level of 0.05 and an estimated test power of 80% for references 104 and 105. To account for the possible non-parametric distribution of the data, 15% more subjects should be added to each group. Another 25% will be added to account for possible dropouts, resulting in 13 participants per group and for greater safety and reliability, 15 patients were established in each group. G*Power 3.1.9.6 was used to perform the calculations.

Materials used in the study:

The biomaterial chosen for this research is the Plenum® OSShp and Plenum® Guide (Brazil) allograft. They are completely synthetic bone grafts and resorbable regenerating membranes (free of animal and human origin).

Plenum® OSShp is a porous synthetic biphasic bioceramic (hydroxyapatite: β - tricalcium phosphate, HA: β-TCP - 70:30%), and the granules are 500 - 1000 µm.

Plenum® Guide is a polydioxanone (PDO)-based synthetic membrane material whose surface morphology closely mimics the extracellular matrix.

Randomization:

All participants will be invited to participate in the research and after signing the informed consent will be randomized into blocks of 4; 60 participants will be randomly divided into 4 groups n=15 Exo (extraction), Exo+Laser (extraction and treatment with 808 nm laser), Exo+Biomat (extraction with biomaterial graft), Exo+Biomat+Laser (extraction and grafting of biomaterial and 808 nm laser treatment). Participants will be randomly allocated by a computer-generated list (Excel) 4.7 CLINICAL PROCEDURE: At the pre-surgical moment, the patient will be submitted to a CT scan (Figure 12) and intraoral scanning (Figure 13) for initial measurement of the vertical and horizontal bone dimensions of the alveolus and between the adjacent teeth of the tooth to be extracted in position in the alveolus and dental arch, and surgical planning, as recommended by the best current dentistry practices, and will sign the Image Use Authorization Term (ANNEX 4). Pre-surgical guidance and delivery of prescriptions with the established drug protocol will also be carried out. All research patients will receive the same post-surgical guidance care (ANNEX 3) and the drug protocol performed for all tooth removal surgery with or without grafting with biomaterials. The tooth will be extracted using an odontosection technique to remove the roots with the least possible trauma. It will not be necessary to lift the soft tissue flap due to the properties of the membrane that will be used, reducing tissue trauma and helping to repair the surgical site. After the extraction, the biomaterial will be added and accommodated to the socket with instruments that allow this insertion and covered by a membrane that will serve as a mechanical barrier, preventing the invagination of the gingival tissue and the formation of keratinized tissue to close the surgical wound so as not to compromise the osseointegration of the bone biomaterial. grafted.

The Exo+Laser and Exo+Biomat+Laser groups will receive, in addition to the drug protocol and guidelines, laser treatment. The Exo and Exo+Biomat groups will use a similar laser device, however, it will not emit irradiation.

In the postoperative period at 3 and 6 months, new intraoral digital scanning and digital computed tomography exams will be performed to take images and perform volumetric analysis with specific software.

Inclusion Criteria:

• All genders, aged between 8 and 17 years, without comorbidities, present satisfactory oral hygiene and present a condition of loss of first or second permanent molars

Exclusion Criteria:

• Habitual use of analgesic and anti-inflammatory medication for other comorbidities, present allergies to the proposed drug protocol, in neurological/psychiatric treatment, presence of teeth with lesions to be treated in the same hemiarch of the tooth to be removed, current smoking habit, pregnant or breast-feeding, presenting photosensitivity disorders, with the presence of neoplasia in the oral region; and patients with operative complications whose surgical time exceeds 90 minutes