The aim of this study is to evaluate the bone loss after extraction. The surgery protocol is flapless, and the teeth are mandibular premolars or molars leaving sockets with 4 walls intact or at least 3 walls intact and the buccal wall at 80% . This study will include 40 patients

Primary objective :

Estimate the percentage of bone volume loss o and the percentage thickness loss of the buccal and palatal cortical for patients who underwent natural healing in the mandibular molar and premolar areas.

Methods :

Before tooth extraction of a premolar or molar in mandibular area by flapless technique, a CBCT preoperative is performed to verify the integrity of cortical and measure the height and width of the residual cavity. Caliper measurements will also be performed during surgery in order to integrate also the thickness of the bone tables and gingival thickness.

After natural healing , the pre-implant scan performed at six months postoperatively will measure the height and width of the grafted cell, to compare measurements and evaluate the dynamics of alveolar resorption.

Inclusion criteria

• patients requiring tooth extraction
• aged 18 to 80
• Patients showing no indication against-General to surgery

Exclusion criteria

• Patient with against-indication for surgical treatment.
• Patients with an important loss of vestibular cortical
• Patients requiring and accepting a bone graft
• Unstabilized periodontal disease or aesthetic indication.
• Inability to maintain a good level of oral hygiene and good cooperation.
• Higher tobacco consumption has 10cig / day
• Acute dental infection

Population of patients aged between 18 and 80 years with one to two posterior mandibular teeth to extract in absence of bone graft and able to benefit from a flapless technique.

NC