In dental repair, it is a very important step to make silicone rubber model for patients. Whether the model is correct or not directly determines the accuracy of the prosthesis. In general, after making silicone rubber model in the mouth of patients, dentists will check the making of impression to see whether the lower surface is intact? Are there any defects? Then what are the defects that need to be remodeled? These 10 situations mentioned below are worthy of your attention.


1、 No tray


The probability of this kind of situation is not high, and it is very easy to check, but it is worth noting that once there is no tray, please make it again immediately.






2、 Separation of impression material and tray


In this case, we should pay attention to the following two situations. 1、 The demoulding position is not at the tooth body, and the area is small. At this time, it is not necessary to make it again, just use glue for retention. 2、 The demoulding position appears at the tooth, or the demoulding area is relatively large, so it needs to be made again at this time.






3、 Incomplete molars


In particular, the frequency of such cases is very high, and clinicians can evaluate whether such defects need to be re taken in combination with the treatment plan. If the molar relationship is maintained and 1 / 2 of the last crown has been taken, it is not necessary to take it again. If the molar needs to be designed to move but not taken completely, please take the mold again. At the same time, when such defects occur, please also indicate whether the molar relationship is maintained in the entrusted processing sheet or the mid-term feedback form, so as to avoid giving the defect description feedback to the clinic due to the unclear scheme during the silica gel acceptance.






4、 No final impression coverage at dentition


Because of the characteristics of the initial impression material, it is difficult to ensure the clarity and accuracy of the tooth shape after the removal of the impression. If the tooth shape is not clear when the silicon offset impression is detected clinically, especially when the gingival margin line is fuzzy, do not hesitate to take the impression again.






5、 Tooth form shortage


Sometimes, because of the insufficient depth of the impression bite or the insufficient amount of the impression, the tooth shape will be in short supply. In clinical practice, doctors can evaluate whether to take it again according to the gingival marginal line. The defect less than 1 / 3 of a single tooth can be repaired in the later stage, but it can not be taken again.






6、 Delamination and fold at the initial and final impression


In general, the initial and final impression are two kinds of color materials. In the clinical examination of silica gel, if the color separation of some parts is particularly obvious, a probe can be used to check whether the edge transition is smooth. If it is found that the two materials are not well combined or there are steps, it is necessary to take the mould again.






7、 Deformation of impression in dentition


If there is any obvious deformation on the surface, please take it again clinically. If there is any inconformity with the normal tooth anatomy, please refer to the actual shape of the patient's mouth for confirmation. If the patient has abnormal teeth, please also note the tooth position in the entrusted processing sheet or provide the oral photo to ensure that the tooth position is photographed clearly. When the silica gel is accepted, the company needs to refer to the relevant data to determine whether it is Defects.






8、 Air bubble, cavity and die undercut


These three defects are also common problems. We can judge whether to take them again according to the position of teeth. Generally, as long as it doesn't occur at the cutting angle and tooth tip, the smaller area can be trimmed later, and it doesn't need to be retaken.






9、 Incomplete curing of impression


In case of uneven color mixing on the surface of the impression, please use a clinical probe to check its hardness. If incomplete curing is found, it may affect the accuracy of the impression, so it needs to be taken again.






10、 Removable denture not removed


Before taking the model, we must remove the movable denture in the mouth of the patient first. If not, the model is not accurate, and it is also made again.