Screw-retained implant crown
In May 2017 our male patient contacted Suba Dentál Clinic with the following complaints:
- At the root canal treated upper right second molar (tooth no. 17) he experienced a sharp radiating pain on bite
In course of the examinations it was found that the root canal treated tooth broke in two on a forceful bite. The tooth proved beyond repair and had to be removed.
Panoramic radiograph from May 2017, prior to extraction
Following 4 months’ healing a CBCT (Cone beam computed tomography) scan was made in order to examine residual bone mass in 3 dimensions prior to implantation. Based on the CT scan it was established that in the area of the missing molar bone height and width were adequate for an implant to be installed (a DIO implant 5 mm in diameter and 10 mm in length). The primary stability of the implant was over 30 Ncm at implantation, a gingiva former was therefore used to seal the implant straight away.
Follow-up panoramic radiograph following implantation, September 2017
Third treatment (5 workdays)
Following 3 months’ healing the permanent crown for the implant was prepared in December 2017. P. Z opted for a screw-retained implant crown, having considered the following benefits:
- Easy repairability: should any injury occur to the ceramics, or if further tooth loss indicates another, more extensive tooth replacement, or if an old implant crown falls due for replacement, the crown can be removed non-destructively.
- Incidental inflammation of the gum or inflammation presenting around the implant is easier to treat with the crown screwed off and screwed back on following treatment.
- Ensures more accurate and professional cleaning by virtue of its removability.
As the implant was sealed with a gingiva former no further surgery was required. By protruding from the gum the gingiva former shapes the gum in such a way as to form an ideal gum contour for the permanent abutment.
Ideal gumline formed by the gingiva former above the implant.
Precision impressions were taken of the implants by means of a special closed-spoon impression coping. A few days later the framework (substructure) was test fitted (tried in) to check whether the impressions were accurate and the denture framework was true. All tooth replacements should now be in perfect alignment with the master cast. This is also when the bite and the length of the framework and teeth are verified.
At handover the finished metal ceramic crown was screwed in place with a special torque wrench with the appropriate torque applied. As the surface of the crown was non-continuous due to the through bolt, a small black cavity was visible that had to be sealed with an aesthetic white filling once the crown was screwed in.
Our patient is thoroughly satisfied with the result and was particularly happy that he had a missing tooth restored by Christmas. J
Implant-borne tooth replacements require as much, if not more care and follow-up as natural tooth-borne varieties.
There is a very close relationship between oral hygiene and the longevity of implants.
Upper view of the screw-retained implant crown on the master cast.
Upper view of the screw-retained implant crown on the master cast with the screwdriver.
Side view of the screw-retained implant crown on the master cast. The cavity on the crown is invisible especially in case of upper rear teeth.
The screw-retained implant crown on the master cast with pink artificial gums ensuring that the crown snugly and seamlessly fits the gums in the mouth
As can been seen, with screw-retained implant crowns the abutment and crown are integrated and cannot be dismantled.
The screw-retained implant crown and the special screwdriver with which to fasten the crown in place.
Bottom view of the upper screw-retained implant crown in the mouth. The discontinuity of the crown is readily discernible, with the gap serving as a slot for the through bolt securing the finished crown in the implant.
Side view of the absolutely aesthetic upper screw-retained implant crown in the mouth with the black cavity through which it was screwed in being invisible.
Bottom view of the upper screw-retained implant crown in the mouth sealed with an aesthetic white composite filling, visible only with the help of a mirror. Under normal circumstances the white filling on the surface of the crown is indistinguishable during eating or speech.