A dental implant is a piece of titanium or other materials that looks like a screw. It is put into the jaw where the missing tooth’s roots were. Over time, bone grows around the implant, which helps to hold it in place. That phenomenon is called osseointegration.
Dental implant already has more than 40 years and the sucess rate is more than 95%. After the osseointegration, the crown can be installed in the implant. Dental implant not only function good and also esthetically pleasant. But it need to have enough bone and soft tissue around, and have enough space around the adjacent teeth.
Implant is a good option to replace the missing tooth. The other option is dental bridge and it need to prepare the two adjacent teeth in order to support the missing teeth.
Dental implant can used to replace missing tooth and also support the denture or fixed full mouth bridge.
All-on-4 dental procedure , invented by Portuguse dentist Paulo Malo, refers to’all’ teethbeing supported ‘on four’ dental implants, a prosthodontics procedure[for total rehabilitation of the edentulous (toothless) patient, or for patients with badly broken down teeth, decayed teeth, or compromised teeth due to gum disease。
Advantage:
- It minimizes the bone augmentation procedure by placing two implants vertically in the anterior region and two oblique implants in the posterior region. By placing two oblique implants, it can avoid the maxillary sinus and inferior alveolar nerve.
- Immediate loading with minimal trauma. The patient can have soft diet after surgery.
Disadvantage:
- For the plan of the final prosthesis, some of the alveolar bone may need to removed.
- Need to have good oral hygiene for the long term periodontal health. Otherwise, one of the implants failed will affected the prosthesis.
The guides consisted of four parts: the base guide, pin guide, implant guide and hybrid provisional guide. (Fig 6) The base guides were stabilised over the remaining teeth and pins were used to anchor the base guides to the maxillary and mandibular bones. The remaining teeth were then extracted, and the implant guide was placed over the base guide for the guided implant surgery. (Fig 7).
Provisional prosthesis
The provisional prosthesis were fixed immediate after surgery. The patient needed to have soft diet for six weeks and waiting for the full osseointegration. (Fig 8)
The bone and soft tissue will be matured after 3 months, final impressions and record were taken for the final prosthesis. (Fig 9)
Final Prosthesis
The patient fully adapted in speaking, eating and the appearance. The laboratory technician will copy all the detail to fabricate the final prosthesis. (Fig 10,11)
Case:
Patient wanted to get rid of the denture。(圖1）
X-Ray & CBCT Checkup (Fig 2): Patient only have right caine, central incisor and left premolar in the maxilla, and left canine, premolar and bridgework.
Treatment plan:
Patient has high caries risk and over erupted lower teeth. All-on-4 implant procedure is recommended.
Facial Analysis:
With the use of photo and video, the dentist measure the mobility of upper and lower lip, the midline and the smileline.(Fig 3), it is essential to plan for the margin of the final prosthsis, and make sure that the margin won’t be show while speaking and smiling. Fig 5, 6).
The lab will merge the patient photo , STL file of the intra-oral scan and Dicom data of CBCT scan for the implant surgery. In addition, the lab will also prepare the virtual smile design in the photo for the assessment.(Fig 7)
Facial Analysis for the Digital Planning of Full Mouth Implant Rehabilitation. Ryan Tak On Tse Compend Contin Educ Dent.2021 March;42(3):128-133
