Dental Implant Crown Dropped Out!

Dental Implant Crown Dropped Out!

Regardless if you have a cement or screw-retained dental implant crown, a common complication is that the crown may sometimes come off. So what should you do if your dental implant crown dropped out?

In the case of cemented crowns, the problem could be due to one of four possibilities. The first is the cementation of the crown onto the dental implant abutment. Under normal usage, the forces exerted on the implant crown during function may lead to failure of the cement layer. This layer holds the crown onto the implant abutment. Assuming that the dental abutment and crown have been designed correctly, the crown and the implant can be cleaned. The crown can then be recemented.

Sometimes the implant abutments are not designed with sufficient retenton and resistance form. This is usually is due to the walls of the implant abutments being too short or too tapered. The implant crown cannot securely grip the implant abutment.

In these instances, if the crown is recemented, it will just fall out again. The implant abutments need to be properly redesigned and remade. A new dental implant crown will also be needed.

Another possibility is that the implant abutment screw connecting the abutment to the implant fixture may break. If the screw fragment can be removed from the implant fixture, and the dental implant crown and the implant fixture are not damaged, a new implant abutment screw can be inserted, and the implant abutment securely bolted to the implant fixture.

The last possibility is that the dental implant crown split into two or more parts. In this situation, a new implant crown will need to be fabricated and delivered to the patient.

For screw-retained crowns, the failure can also take place at one of three points. Firstly, the implant abutment screw can fracture, leading to dislodgment of the dental implant crown. Similar as to with the cemented implant crowns, if the crown and the implant fixture are undamaged, the implant abutment screw can be replaced.

If a titanium base is used, it may debond from the implant crown. If the crown is intact, the crown and the titanium base can be cleaned and bonded together again. If the crown has damaged, it will need to be remade.

Lastly, the implant crown may have suffered a catastrophic fracture. A new implant crown would need to be fabricated and inserted.

If you are experiencing a problem with your implant crown, Contact Us to schedule an appointment to learn what treatment options are available to you.

Abutment Screw Fracture

Abutment Screw Fracture

The dental implant fixture is connected to the implant-retained crown or implant abutment with a retaining screw, know as the implant abutment screw. This is usually a titanium or stainless steel screw that is tightened to a particular torque value. This is known as the Preload or clamping force on the implant abutment screw.

After the dental implant and crown has been in function for a period of time, this retaining screw is subjected to vertical and lateral forces, that may result in the implant abutment screw loosening, or being damaged and breaking. If the implant abutment screw fractures, the implant crown will drop out.

When this happens, part of the implant abutment screw may be still embedded within the dental implant fixture. Sometimes this can be removed easily by turning the broken fragment with an explorer or ultrasonic scaler. If this does not work, most implant systems will have a screw removal kit that can be used to retrieve the fractured implant abutment screw that is custom designed for this purpose.

Fig. 1 Fractured Abutment screw in Implant Fixture.

Fig. 2 Implant Crown with Broken Abutment Screw

Fig. 3 Intact Abutment Screw

Fig. 4 Fractured Abutment Screw removed from Fixture

If the implant abutment screw can be removed without damaging the internal screw threads of the implant fixture, the dental implant crown can be reconnected to the implant fixture and a new implant abutment screw inserted and tightended to the appropriate preload.

However, if the screw threads are damaged, a replacement screw cannot be used. Some implant systems allow for the implant fixtured to be retapped, and a rescue implant abutment screw, which has a slightly larger diameter, can be used to secure the implant crown.

If such an option is not available, then a custom post can be fabricated, as is done with root canal treated teeth. This post is then cemented into the implant fixture, and a crown is cememnted onto it.

If this is not possible, the implant will need to be surgically removed. After a period of healing, a new dental implant fixture is inserted in the same position. Once fusion of the dental implant fixture to the jaw bone has occured, a new implant crown can be fabricated. This process usually takes 6-8 months to be completed.

If you are facing a similar issue with one of your dental implants, Contact Us for a comprehensive examination. We will assess your specific issue and inform you of the treatment options that are available to you.

Fig. 5 Cast Post Core in Implant Fixture

Managing Broken Teeth

Managing Broken Teeth

If you find yourself with broken teeth, it can be a true dental emergency. Whether it's due to trauma or biting down on something hard, such as a small stone or bone fragment, the fracture may vary in severity.

In some cases, the tooth can be smoothened or restored with an adhesive restoration. But for more catastrophic fractures, tooth extraction may be necessary. This can be done at an emergency appointment or scheduled for a later date if needed. In situations where extraction is delayed, removing the tooth nerve may be required to alleviate pain and discomfort.

When dealing with a missing tooth, there are four treatment options to consider. While no treatment may suffice for back teeth, most patients prefer replacing a front tooth. Options include a removable partial denture, a dental bridge, or a dental implant. Of these options, the dental implant stands out as the optimal solution. It doesn't involve adjacent teeth and provides superior aesthetics and functionality.

Throughout the dental implant treatment process, the challenge lies in ensuring a suitable tooth replacement.

Fixed provisional restoration are the preferred solution as they afford greater comfort and are less disruptive. If the neighboring teeth are intact or have small fillings, they can be utilized to seamlessly support the interim restoration. If the clinical crown of the fractured tooth is intact, it can be adhered directly to the adjacent teeth. In more complex cases where the affected tooth is broken into multiple fragments, an impression will be taken to create a provisional restoration out of composite dental resin. It effectively fills the gap left by the broken tooth and restores both form and function.

For patients with higher aesthetic demands, the adhesive Maryland Bridge is recommended. Crafted with a metal framework overlaid with porcelain, this restoration allows for greater customization to achieve a natural blend in both shape and shade with the existing dentition.

In some cases, adjacent teeth with crowns can provide support for a provisional bridge with a cantilevered pontic or replacement tooth. Additionally, patients with existing implants next to the broken tooth can benefit from a provisional restoration connected to the implant with a cantilever pontic. However, if fixed provisional restoration is not feasible or cost-effective, a removable partial denture can be used.

After the broken tooth is extracted, a 3-month healing period allows for the assessment of available bone volume and the need for bone grafting. A minor surgery follows to insert the dental implant into the jaw bone. After another 2-4 months of bone healing, a definitive restoration is fabricated through an impression.

While the process of replacing broken teeth may seem complex, with multiple steps and stages, it typically takes around 6-8 months. If you require further information on broken teeth replacement options, feel free to Contact Us.

Managing Dental Implant Angle

Managing Dental Implant Angle

Is your dental implant angle off? you facing challenges with dental implants that are not in an ideal position? 

Whether the dental implant angle was a deliberate decision to avoid bone grafting or a surgical oversight, we understand the need for a solution.

Our expertise lies in compensating for misangulated implants prosthetically, using specialized components.

By carefully considering factors such as angulation, position within the bone, and implant depth, we can devise a bespoke plan to rectify the situation.

In more severe cases where the misalignment is substantial, implant removal procedures may be necessary, followed by grafting and healing.

Once the site is ready, we can place a new implant in a more optimal position and restore it to ideal function and aesthetics.

If the malignment is mild, a cemented restoration can be used to restore the clinical portion of the tooth. A ceramic or metal post is connected to the dental implant with a retaining screw, then a crown is fabricated to fit this abutment. This is similar to crowns which are done on teeth.

Care has to be taken during the cementation to ensure that all the excess cement is removed, to prevent the extra cement from causing infection under the gums.

The main disadvantage of a cemented crown is retrievability of the crown. Occassionally, the crown may need to be removed for maintenance of the implant. Cemented crowns sometimes cannot be removed without breaking, and a new crown might need to be fabricated.

Specialized parts known as angled multiunit abutments can occassiuonally be used to redirect the direction of the implant retention screw.

These come in predetermined angulations, resulting in some limitations to how much correction can be made.

The extra parts increase prosthetic complications as well as the cost of restoring the implant.

A more innovative solution has been the development of dynamic axes screws, such as the Dynamic Abutment. These sophisticated screws allow for engagement at an offset of up to 25 degrees. In most cases, this is sufficient to redirect the access hole from the outer surface of the crown to the inner surface.

They not only do not require additional restorative space, but do not require additional components. The conventional abutment screw is exchanged for the dynamic axis screw.

These can be used either as part of a conventional analog work flow, or as part of a integrated digital CAD/CAM workflow.

The reduced number of parts and the larger implant retaining screw also decrease the incidence of prosthetic problems.

These revolutionary screws have significantly impacted how these cases can be managed, reducing the number of implants that have to be removed and lowering the costs of restoring these cases.