Enucleation combined with guided bone regeneration in small and medium-sized odontogenic jaw cysts

BACKGROUND The odontogenic jaw cyst is a cavity containing liquid,semifluid or gaseous components,with the development of the disease.In recent years,with the rapid development of oral materials and the transformation of treatment of jaw cysts,more options are available for treatment of postoperative bone defect of jaw cysts.Guided bone regeneration(GBR)places biomaterials in the bone defect,and then uses biofilm to separate the proliferative soft tissue and the slow-growing bone tissue to maintain the space for bone regeneration,which is widely used in the field of implantology.AIM To observe the clinical effect of GBR in repairing bone defect after enucleation of small and medium-sized odontogenic jaw cysts.METHODS From June 2018 to September 2020,13 patients(7 male,6 female)with odontogenic jaw cysts were treated in the Department of Oral Surgery,Ninth People’s Hospital,Shanghai Jiao Tong University School of Medicine.Adults without hypertension,heart disease,diabetes or other systemic diseases were selected.The diagnosis was based on the final pathological results:11 cases were diagnosed as apical cysts,one as primordial cyst,and one as dentigerous cyst.The lesions were located in the maxilla in seven cases,and in the mandible in six cases.All cases were treated with the same method of enucleation combined with GBR.RESULTS Three to four months after the operation,the boundary between the implant site and the surrounding normal stroma was not obvious in patients with small-sized odontogenic jaw cysts.The patients with tooth defects were treated with implant after 6 mo.For the patients with medium-sized odontogenic jaw cysts,the density of the center of the implant area was close to the normal mass at 6 mo after surgery,and there was a clear boundary between the periphery of the implant area and the normal mass.The boundary between the periphery of the implant area and the normal mass was blurred at 8-9 mo after surgery.Patients with tooth defects were treated with implants at>6 mo after the operation.CONCLUSION Enucleation combined with guided bone regeneration in small and medium-sized odontogenic jaw cysts can shorten the time of osteogenesis,increase the amount of new bone formation,reduce complications,and improve quality of life.

Intracystic negative pressure may promote bone formation around jaw cysts

The growth and enlargement of jaw cysts are associated with raised intracystic pressure and bone resorption surrounding the cysts.The major bone-resorbing cells are the osteoclasts.They are acting under the influence of local bone-resorbing factors: prostaglandins,proteinases and cytokines.It was found that positive pressure enhanced the expression of IL-1αmRNA and protein in epithelial cells of odontogenic keratocyst,and increased the secretion of matrix metalloproteinase and PGE2 in a co-culture of odontogenic keratocyst fibroblasts and epithelial cells.However,the signal intensities for IL-1α mRNA and protein in the epithelium were significantly decreased after marsupialization which relived intracystic pressure.Experimental study indicated that intermittent negative pressure could promote osteogenesis in human bone marrow-derived stroma cells(BMSCs) in vitro.We propose a hypothesis that bone formation around the cyst of the jaws would be stimulated by intracystic negative pressure.

Efficacy of bone grafts in jaw cystic lesions:A systematic review

BACKGROUND Bone grafts have been applied for many years in orthopedic surgery to assist with bone repair for defects or bone discontinuity caused by trauma and tumors as well as periodontal defects.Jaw cysts are another common benign disease of the maxillofacial region which may lead to pathological bone fracture,loss of teeth,and infection.However,whether bone grafts are beneficial for bone regeneration in jaw cystic lesions and when bone grafts should be used remains unclear.AIM To study the efficacy of bone grafts compared to spontaneous healing in the treatment of jaw cystic lesions.METHODS A literature search was performed in Medline,Cochrane Library and Embase to identify related articles published in English in the last ten years.The following key words and Me SH terms were used:“jaw cyst”,“cystic lesion”,“odontogenic cyst”,“periapical cyst”,“dentigerous cyst”,“follicular cyst”,“keratocyst”,“treatment”,“surgery”,“bone graft”,“enucleation”,“cystectomy”,and“bone regeneration”.Case reports,clinical trials,clinical studies,observational studies and randomized controlled trials were included.Study quality was evaluated.RESULTS Ten studies(n=10)met the inclusion criteria.Five studies reported spontaneous bone healing after enucleation,three studies investigated the efficacy of various bone grafts,and two randomized comparative studies focused on the comparison between spontaneous healing and bone grafting.Over 90%of bone regeneration occurred within 6 mo after bone grafting.The bone regeneration rate after cystectomy showed great variation,ranging from 50%to 100%after 6 mo,but reaching over 90%after 12 mo.CONCLUSION While the long-term superiority of bone grafting compared with spontaneous healing after cystectomy is unclear,bone grafts accelerate the process of healing and significantly increase bone quality.