Observation On The Effect Of Alveoloplasty Combined With Alveolar Bone Defect Reconstruction In Immediate Extraction And Full-Arch Immediate Implant Restoration

Objective: To evaluate the clinical effect of alveoloplasty combined with alveolar bone defect reconstruction in 20 patients with immediate extraction and full-arch immediate implant restoration.Materials and Methods: From June 2017 to December 2022,20 patients with immediate extraction and immediate loading of immediate implant-supported full-arch prostheses were selected in Oral Implant Center of Inner Mongolia People’s Hospital.A total of 119 implants were implanted in 20 pairs of monobtained-bridge prostheses(10 upper and 10 lower).Surgical SAC assessment and aesthetic risk assessment were performed according to the ITI guidelines.Preoperative intraoral and facial photos were recorded to determine the maxillofacial relationship and vertical distance,and the imaging examination and digital implant plan design were perfected.The remaining teeth were extracted,the granulation tissue in the extraction socket was removed,the extraction socket was thoroughly scratched,the horizontal incision was made along the crest of the alveolar ridge,the longitudinal incision was added,and the full thickness mucoperiosteal flap was inverted.According to the preoperative design,the alveolar process was repaired with ultrasonic bone curettage,rongeur and bone drill,and the holes were prepared successively at the implant sites.The bone blocks obtained by alveolar bone trimming were used for alveolar bone defect reconstruction.The immediate loading polymethacrylic resin provisional restoration was made by chair-side immediately after operation.Three months to one and a half years after operation,the titanium cutting frame and polymer veneering porcelain restoration bridge were repaired.The height and width of the alveolar bone were measured in CBCT images of 20 patients before and immediately after the operation,and the changes of alveolar bone were analyzed.The retention rate of the implant and surgical complications during the follow-up period were recorded.Two patients who underwent alveolar bone trimming and alveolar bone defect reconstruction were selected from the 20 patients.The bone resorption height,gray value,and bone graft area of the marginal bone of the implant at the alveolar bone defect reconstruction site immediately after surgery and 15 months after surgery were measured to evaluate the clinical effect of alveolar bone trimming combined with alveolar bone defect reconstruction in immediate extraction and full-arch immediate implant restoration.Results: None of the 20 patients were lost to follow-up.One implant was lost,and the cumulative implant survival rate was 99.2%.The incidence of alveolar bone erosion was 100% in 20 patients.The alveolar bone height of the anterior teeth changed most after surgery.The alveolar bone height of the maxillary anterior teeth changed by2.49±2.41 mm and that of the mandibular anterior teeth changed by 2.17±1.70 mm.The highest incidence of alveolar bone remodeling was 100% in the maxillary anterior tooth area,and the lowest incidence was 30% in the maxillary molar area.The frequency of alveolar bone remodeling increased in the order of maxillary and mandibular molar,premolar,and molar.After alveolar bone remodeling,the increment of alveolar bone width in the molar,premolar,and anterior areas of the upper and lower jaws increased in sequence.Only in the maxillary molar area,the alveolar bone width decreased in 1.5% of sites.During the follow-up,no surgical complications occurred.The average value of marginal bone loss after 15 months of 6alveolar bone defect reconstruction sites in 2 patients with alveolar bone dressing combined with alveolar bone defect reconstruction was: The average relative ratio of bone graft area at 15 months after surgery and immediately after surgery was 90.7%.There was no significant difference in gray value of alveolar bone defect reconstruction site immediately after surgery and 15 months after surgery.In typical cases,alveolar bone repair combined with alveolar bone defect reconstruction can achieve good clinical results in immediate extraction and full-arch immediate implant restoration.Conclusions: In the surgery of immediate extraction and full-arch immediate implant restoration,alveolar bone remodeling mostly occurred in the maxillary and mandibular anterior teeth,followed by the premolar area.The rate of alveolar bone remodeling was the lowest in the molar area.Before and after alveolar bone remodeling,the alveolar bone height loss and width gain in the anterior teeth were higher than those in the molar and premolar areas.During the follow-up,one implant fell off,and no surgical complications occurred,indicating that the surgery achieved good clinical results.According to the measurement and analysis of the bone graft site in 2 patients with alveolar bone trimming combined with alveolar bone defect reconstruction,the short-term follow-up clinical effect of alveolar bone trimming combined with alveolar bone defect reconstruction was good.