Digital Versus Conventional Impression Used in The CAD / CAM Constructed 4- Implant Supported Mandibular Overdenture Base: Bone Height Changes
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 20
- 试验地点
- 1
- 主要终点
- Bone height changes
研究概览
简要总结
This clinical study was done to compare between digital with conventional impression used in the CAD/CAM constructed 4- implant supported mandibular overdenture base regarding their effect on the bone height changes
详细描述
The patients were classified randomly into two equal groups according to impression techniques of mandibular implants and residual ridge:
Group 1: conventional impression group (CIG). Group 2: digital impression group (DIG).
For group 1 :
- Unscrew the provisional acrylic denture from the implants
. - The long transfer copings (implant level) were screwed to the implants.
- The transfer copings were splinted with orthodontic ligature wire and light cure composite resin before impression making to prevent movement of the transfer coping during impression procedure.
- A stock/special tray was perforated to allow passing of the transfer copings through it without interference and permit unscrewing of the transfer after setting of the impression
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Treatment
- 盲法
- Single (Participant)
入排标准
- 年龄范围
- 40 Years 至 60 Years（Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •All patient wearing maxillary conventional denture.
- •All patients had temporary mandibular overdenture supported by vertically inserted 4-implant at least six months ago.
- •A Cone Beam Computed Tomography (CBCT) done to verify the accurate position and success of the inserted implant.
- •They were healthy, free from any systemic diseases relating to bone resorption such as uncontrolled diabetics or osteoporosis. This was achieved through medical history and clinical examination by physician.
- •At least 15 mm restorative space must be available (from the mucosa covering the crest of the residual ridge to proposed occlusal plane) to permit construction of all types of tested prosthesis (class I according to Ahuja and Cagna). This was detected by a tentative jaw relation.
- •All patients are of angel's class I maxillo-mandibular relationships.
排除标准
- •Patients had head and neck radiotherapy, patients with bleeding disorders or hepatic patients.
- •Patients with metabolic disorders as diabetes mellitus, osteoporosis and hepatic disorders that might affect osseointegration.
- •Long term immunosuppress and corticosteroid drug therapy.
- •Patient with abnormal habits as clenching and bruxism.
- •Smoking patient.
- •Uncooperative patients.
- •Neuromuscular diseases.
- •Patient with problems in TMJ.
研究组 & 干预措施
conventional impression procedures
Implant analogues were screwed to the transfer copings inside the impression and the master cast were obtained. Attachments were screwed to the analogues and metal housing wasplaced on their position on master cast. Master cast will be scanned extra orally to obtain STL file of the master cast.
干预措施: conventional impression group (Other)
digital impression procedures
A digital scanner (shining 3D scanner, Germany) was utilized to fabricate the definitive prostheses. The attachments were screwed to the implants intra orally and metal housing on their position which scanned by using intra oral scanner.
- Intra oral scanner transformed into a virtual volume the three-dimensional geometry of dental arches using the principle of structured light. A scanning stitching strategy carried out by the same experienced investigator and applied to DIG group for the attachments on their position on implants.
- The software automatically was applied a stitching algorithm in order to merge the two halves, based on the area between the two anterior implants, shared by both the separate scans.
- The virtual model was created of the dental implant and attachments in position which used to obtain 3d printed master cast by using 3D printer (WANHAO desktop 3D printer, Zhejiang, China).
干预措施: digital impression group (Other)
结局指标
主要结局
Bone height changes
时间窗: one year
Long cone paralleling technique and a film holder designed specifically for implant imaging were used for intraoral radiograph. To maintain the same film- implant distance and cone implant distance, a modification was carried out for the film holder. This modification is a hole drilled exactly above the implant fixture so the distance was maintained during subsequent film exposures. A long screw of the impression coping was used to secure the holder to the implant. Through this modification, standardized radiographs were achieved.
次要结局
未报告次要终点