Application Study Of Apical Preservation Combined With Guided Bone Regeneration In Jaw Cyst Surgery

Objective To explore the curative effect of apical preservation combined with guided bone regeneration in jaw cyst surgery.The aim is to preserve the involved teeth in the lesion area,promote osteanagenesis and accelerate bone remodeling in the bone defect area,and shorten the postoperative healing time,thus providing a new idea for jaw cyst surgery.Method1.From October 2017 to June 2018,55 cases of Odontogenic Cyst(OC)treated in Department of Oral & Maxillofacial Surgery were selected as the study subjects,aged 15-45 years.They were randomly divided into 2 groups,including 15 cases in the experimental group and 40 in the control group.2.All patients took Cone Beam Computed Tomography(CBCT)and/or Digital Panoranic Radiography(OPG)before operation to evaluate the OC position range.The number of OC caused dysfunctional teeth was counted,and dental pulp vitality was measured with pulp vitality tester.Involved non-vital teeth were treated with single visit root canal therapy 3 days before operation.All patients underwent complete ultrasonic supragingival scaling one week before operation;lesions in the acute stage of inflammation were controlled before elective surgery.3.In the experimental group,periapical curettage was performed during the surgery to preserve the root tip,and only Bio-oss bone dust was used to cover the cyst involved lack of part of the root exposed to jaw,and the surface of bone graft material was covered with Haiao artificial biomembrane.The control group underwent simple cyst excision plus apicoectomy.4.The subjects were followed up at 3,6,and 12 months postoperatively,and the number of teeth recovered from cyst involvement was counted in the two groups of patients.Bone regeneration and reconstruction were analyzed by CBCT or OPG in the apical preservation plus bone augmentation areas and the spontaneous healing area.Result1.Except for delayed wound healing in 4 patients of the control group,the rest of the patients healed well after operation.No symptoms like biomembrane exposure or bone dust loss occurred in the experimental group.At 6 months after operation,no recurrent symptoms occurred in either group,and the dislodged and expanded soft and hard tissues caused by the cysts basically returned to their normal positions.2.Postoperative follow-up examination for the teeth recovered from OC involvement consisted of 45 teeth in the experimental group and 144 in the control group.The differences in the number of involved teeth and cyst caused dysfunctional teeth were compared between the two groups,and P > 0.05 was obtained,indicating that there were no significant differences,and that the two groups were comparable.3.At 3,6,and 12 months after operation,the recovery of tooth function was re-examined.According to statistical analysis results,P < 0.05 was statistically significant,indicating that the normal function recovery in cyst involved teeth in the experimental group was faster than that in group B,and that the efficacy was better.4.Examination of oral CBCT and OPG of the experimental group At 3 months after operation,Imaging examination revealed that the gray value of the apical bone augmentation area in the OC residual bone cavity in the experimental group was significantly higher than that in the autogenous healing area;part of the new bone were formed in the bone augmentation area,and their gray value was slightly higher than that of adjacent healthy bone tissue.There was little change in osteogenesis in the spontaneous healing area compared to that before operation.6 months after operation,the OC residual bone cavity was significantly reduced to the normal range,the bone texture of the apical bone augmentation area was gradually formed,and osseointegration proceeded in an orderly manner.The bone cavity boundary was faintly visible,but the bone mineral density was not uniform.In the spontaneous healing area,osteogenesis still progressed slowly,no obvious trabecular structure was visible,and transparent zone of the bone cavity was still visible.After 12 months of operation,the apical bone graft material was roughly absorbed,and the bone texture was clearly visible.Its mineral density was close to that of the surrounding bone without obvious boundaries.The bone mineral density in the spontaneous healing area was slightly higher than 6 months ago,but the osteogenic quality was significantly worse than that of the apical bone augmentation.Local low-density images were still visible in the center of the bone cavity in some cases.Conclusion1.By using the method of apical preservation and guided bone regeneration in odontogenic cyst surgery,there was no recurrence of the cyst after 12 months of follow-up.2.The use of apical preservation combined with guided bone regeneration during odontogenic cyst operation is beneficial to preserving cyst involved teeth and accelerating the stabilization of loose teeth.3.Apical preservation combined with guided bone regeneration stimulates osteanagenesis at the apex of bone cavity after OC surgery.This technique is feasible and conducive to postoperative bone repair and reconstruction,providing a new idea for jaw cystectomy.