Clinical Evaluation Of Marginal Bone Resorption After Three Years Of Restoration With Thommen Implant

Objective: To analyze the marginal bone resorption after three years of restoration with Thommen implant,to evaluate the clinical effect of Thommen implant,providing data reference and clinical guidance for subsequent research and application.Methods: From June 2013 to December 2017,53 patients were treated in the Implant Center of Stomatology Hospital affiliated to Dalian Medical University,They are including 36 males(67.9%)and 17 females(32.1%),with an average age of 45.5 which eldest in the group is 76 and youngest is 18.Patients totally implanting 147 Thommen implants,with 77 teeth in the maxillary(including 20 teeth in maxillary anterior region,25 in the maxillary premolar area,32 teeth in maxillary molars),and 70 teeth mandibular,(including 8 teeth in mandibular anterior teeth,14 teeth in mandibular premolars,48 teeth in mandibular molar region),respectively.Among them,112 implants with conventional implant surgery,8 implants with maxillary sinus lift,11 implants with osteotomy,8 implants with guided tissue regeneration,6 implants with immediate implant,and 2 implants with flapless implant.Moreover,all implants remove the stitches 7 to 10 days after surgery,stage?surgery was arranged 3 to 6 months after surgery for submerged implant,and to finish implant restoration 2 weeks later.And restoration was arranged 3 months after surgrey for non-submerged implant.Furthermore,to assess the marginal bone loss after 3 years of restoration with Thommen implant,all the patients were took X-ray radiographs,calculated the absorption value of marginal bone,and measured implant gingival index,modified plaque statistical index and implant survival rate,patients were also asked for implant restoration degree of satisfaction.Results:(1)All patients felt well in the postoperative,without pain and swelling.Only one case had a wound slight dehiscence and slight periosteal exposure at one week after surgery,which due to suture tension.Treated by washing and medicine anti-inflammatory therapy,the case was healed in second week.No postoperative complications were found in a the remaining patients.(2)One implant fell off and the survival rate was 99.3%.The patient smoked more than 10 cigarettes a day and had poor oral hygiene,he had removed the loosening implant and was scheduled to perform re-implantation for 6 months.(3)The gingival index,modified plaque index examination: only one patient with long-term smoking cause gum index grade 2,modified plaque index for grade 3,poor oral hygiene;two patients with moderate inflammation of the gums,three patients with scaling and health education.(4)The average marginal bone resorption value of 147 implants was 0.55 mm±0.40.Mesial marginal bone resorption value was 0.54 mm ± 0.38,and distal marginal bone resorption value was 0.56 mm±0.43.(5)All cases were completed restoration in 3~6 months after operation,only one case with repair abutment loosening,removed the prosthesis,reapplied the force to 25 Ncm for abutment screw,and rebonded restoration.(6)All 53 cases were satisfied with the restoration of function such as mastication and speech after implant restoration,only one patients expressed a desire to reduce anterior teeth crown length and extend anterior crown.However,if prolonged the lower anterior teeth crown,the ratio of crown to root is too large and is not conducive to the long-term efficacy due to the insufficient mandibular jaw bone.Conclusion: This clinical study showed that the low marginal bone loss value of Thommen implant after three years of restoration.It reduces bone resorption,increases the survival rate of implant,and kprovides long-term stability for patients.