In the maxillary molar area, especially when the distance from the base of the maxillary sinus to the alveolar crest is too small and insufficient bone tissue support is lacking, sinus elevation is generally used to solve the problem of insufficient bone mass. This is also a major difficulty in oral implants.
Professor Wei Bin warns us that a comprehensive preoperative assessment is essential to achieve accurate maxillary sinus lifting!
This should be the most comprehensive preoperative assessment in history, with a total of 15 assessment points including hard tissue assessment and soft tissue assessment. Let's take a closer look at the cbct images and the effective messages conveyed to us by clinical examinations. This is also the most detailed preoperative assessment in history, allowing us to understand the level of surgical difficulty of the patient at hand, and Professor Wei Bin told us the detailed method of coping with each level of difficulty, so that we no longer panic in the face of maxillary sinus lifting
Assessment of hard tissue
The first is the assessment of the hard organization, which includes 12 points. Before, before listening to Director Wei Bin's speech, the little rookie would only stare at the bones shown by the cbct in a daze, a paste. Now look at the cbct film, these 12 points correspond to the past, the understanding of the difficulty of surgery and the surgical measures to be taken are really clear!
1. Alveolar crest top line
Difficulty 1: The alveolar crest top line and the bottom line of the maxillary sinus are clear, and the operation can be performed using conventional surgery
Difficulty 2: There are unclear parts at the top of the alveolar crest, and the soft tissues in the tooth socket need to be scratched clean and bone grafted
Difficulty three: the alveolar crest top line is complex, there is no bone regeneration in the extraction socket, and soft tissue scratching and gbr are required
Non-indications:
The maxillary sinus mucosa and alveolar mucosa heal, and if there is no alveolar bone at the incision site, it is easy to cause postoperative mucosa to crack and cause infection.
2. Maxillary sinus bottom line
Difficulty two: the bottom line of the maxillary sinus is not clear, and the mucous membrane at the bottom of the maxillary sinus may be perforated
Difficulty three: complex forms of calcides can be seen in the maxillary sinuses, the bottom line of the maxillary sinuses is complex, and special attention should be paid to the design of the window
Non-indications: the bottom line of the maxillary sinuses is not clear, and the mucous membrane of the bottom of the maxillary sinuses may be perforated when peeling off
3. Distance from the base of the maxillary sinus to the top of the alveolar crest
Difficulty 1: The distance from the bottom of the maxillary sinus to the top of the alveolar crest is 8 mm, and implants can be implanted at the same time
Difficulty 2: The distance from the bottom of the maxillary sinus to the top of the alveolar crest is 3-5 mm, and it is recommended to postpone implantation
Difficulty 3: The distance from the bottom of the maxillary sinus to the top of the alveolar crest is less than 3 mm, and the mucosa of the maxillary sinus is hypertrophied, and it is recommended to postpone implantation
Non-indications: the connection of the maxillary sinus mucosa to the alveolar mucosa is a contraindication to surgery
4. Alveolar crest top width
Difficulty 1: The width of the alveolar crest top is above 6mm, no gbr is required, and implants implants at the same time
Difficulty 2: The width of the alveolar crest top is 5mm, gbr is required, and if the distance from the top of the alveolar crest to the maxillary sinus is 5 to 9mm, the implant can be implanted at the same time.
Difficulty three: the width of the alveolar crest top is about 2 mm, and maxillary sinus lifting and gbr are performed at the same time, and implanted into the implant after a period of no-load healing
5. Near and far distance of the inner wall of the maxillary sinuses
Difficulty 1: 20mm near and far middle distance, only need to prepare a window, you can peel off the maxillary sinus near and far mucous membrane
Difficulty two: near and far middle distance 30mm, prepare a window, but need to extend the window distance between the near and far
Difficulty three: the length of the inner wall of the maxillary sinus is 35mm, and 2 or 3 windows should be prepared, often bounded by the zac line, and one window in the near middle and one window in the far middle.
6． Width of the maxillary sinuses
Difficulty 1: Width is 16mm, side window (flip-in type or uncovered type)
Difficulty 2: The width is 19mm, and the width is large, which is suitable for surgery with the uncovered cover
Difficulty three: For the case of toothless jaw, the window opening site is closer to the top, the maxillary sinus at the window opening is wider, and the nasal side mucosa is more difficult to peel off, which is suitable for surgery with uncovered cover
7. The height of separation within the maxillary sinuses
Difficulty 1: There is no separation on the sagittal and coronal ct images, and conventional surgery can be used
Difficulty 2: Sagittal ct images show the presence of separations of less than 5 mm at the base of the maxillary sinuses
Difficulty 3: Sagittal ct images show that the separation is protruding from the base of the maxillary sinus, such as the separation at the base of the maxillary sinus is 5 mm wide, the tip is 1 mm wide, and the height is 8 mm
Non-indications: ct images show the presence of a 4- to 5 mm high septum on the sagittal surface, and when the maxillary sinus mucosa is peeled from the buccal side window, the separated buccal mucosa can be peeled, but the separated jaw side mucosa cannot be peeled off. In addition, due to the presence of depressions in the bottom of the maxillary sinuses and the complex morphology, it is easy to cause perforation when peeling off the mucous membrane of the bottom of the maxillary sinuses, which should be regarded as non-indications.
8. The thickness of the bone wall of the side window opening site
Difficulty 1: The thickness of the bone wall of the window opening part is about 2mm, and it can be turned into the type or uncovered.
Difficulty two: the thickness of the bone wall is less than 1mm, suitable for the use of the flip-in type, the bone wall of the window opening site and the maxillary sinus mucosa together to lift; if the cover surgery is used, it is not easy to obtain stability, and it is easy to form dead bone
Difficulty 3: the thickness of the bone wall at the window opening site is 3mm, and the presence of the posterior upper alveolar artery can be seen, and the possibility of perforation of the maxillary sinus mucosa is very large when grinding the bone groove;
Grinding of the bone groove and peeling of the bone wall should be carried out in stages.
9. Alveolar intraosseous lesions
Difficulty 1: There is no image of suspicious lesions in the alveolar bone of the toothless area
Difficulty two: there is less than 4 mm of bad granulation tissue at the top of the alveolar bone, it is recommended to perform gbr after scraping the bad granulation tissue
Difficulty three: there is bad granulation tissue of more than 4 mm in the maxilla, and bone grafting and gbr are required after the granulation tissue is removed
Non-indications: significant transmission of alveolar bone communicates with the nasal mucosa; inability to peel off and lift the maxillary sinus mucosa
10. Lesions of adjacent root tips
Difficulty 1: There is no lesion around the root tip of the adjacent tooth; the maxillary sinus mucosa around the adjacent tooth can be removed by conventional methods
Difficulty 2: There is a lesion at the root tip, more than 2 mm from the bottom of the maxillary sinus, and root canal treatment is required before surgery
Difficulty 3: There is a significant lesion at the root tip, less than 2 mm from the bottom of the maxillary sinus, and root canal treatment is required before surgery
Non-indications: part of the root tip lesion of the second anterior molar is communicated with the maxillary sinus mucosa, which predisposes to chronic maxillary sinusitis; it should be regarded as a non-indication for surgery
11． Adjacent root tip position
Difficulty 1: No root tip protrudes into the maxillary sinus; conventional surgical methods can be used to peel off the maxillary sinus mucosa
Difficulty 2: The root tip protrudes less than 2 mm in the maxillary sinus, and the mucous membrane of the maxillary sinus is peeled off when the alveolar bone at the root tip is clearly seen
Difficulty 3: The root tip protrudes about 2 mm inside the maxillary sinus, and when the perimonal membrane of the root cuspid is found to be connected to the maxillary sinus mucosa, the operation should be terminated immediately.
Non-indications: the root tip protrudes about 3 mm in the maxillary sinus; because the root tip is too prominent, it is difficult to peel off the mucous membrane around it, which is easy to cause mucosal perforation, which should be regarded as a non-indication for surgery.
12.ct value
Bone density is low in the posterior maxillary area, usually of class d3 or D4 bone classified by lekholm and zalb bone density.
Bone density is judged by ct value. Bone density will affect the initial stability of the implant after implantation; as a reference for whether to implant implants at the same time.
Soft tissue assessment
13. Hypertrophic thickness of the maxillary sinus mucosa
Difficulty 1: The maxillary sinus mucosa is free of hypertrophy and conventional surgical methods are used
Difficulty 2: The thickness of the maxillary sinus mucosa is about 3 mm
Difficulty three: Hypertrophy of the maxillary sinus mucosa is close to 8 mm
Non-adaptation: the thickness of the maxillary sinus mucosa is more than 8 mm, and there is no room for lifting the mucous membrane in the maxillary sinus, which is a non-indication for surgery.
14. Maxillary sinus lesions
Indications: Clear projection images in the maxillary sinuses, no mucosal hypertrophy and lesions
Non-indications: root canal treatment of the lateral root of the first molar tooth and periodontal infection causing maxillary sinusitis, there is a fluid accumulation in the maxillary sinuses; it is a non-indication for surgery.
15. Blood vessels on the bone wall at the site of the window opening
Difficulty 1: Walk without blood vessels, using conventional methods
Difficulty two: there are blood vessels with a diameter of less than 2 mm on the inner side of the bone wall of the window opening site
Difficulty three: there are blood vessels with a diameter of 2-3 mm on the inner side of the bone wall at the window opening site; when grinding the bone groove or peeling off the bone wall, special attention should be paid not to injure the blood vessels.
Non-indications: if CT shows that the posterior upper alveolar artery enters the maxilla and runs transversely through the window opening site, the blood vessels with a diameter of more than 3 mm walk on the lateral bone wall of the maxillary sinus at the window opening site, which is a non-indication for surgery.
After reading the whole text, is it the same as the little rookie, I think there are many things to consider for maxillary sinus lifting ~ When learning with the director, the little rookie marveled at how to come up with the treatment plan so quickly, and each step was considered in advance, which was really annoying~
However, they can't go thousands of miles without accumulating steps, and their achievements are slowly accumulating ~ so at the beginning they are clumsy that each point of consideration corresponds to the past, and one day they can also skillfully and calmly cope with the complexity of surgery ~ cheer together~
Author Profile: Huang Jingjing Master of Restoration