Single Piece Implants- Disadvantages

Single Piece Basal / One Piece Compressive / Monobloc Conventional Implants- Disadvantages

What are the types of Dental Implants? – Clinically we can divide implants into Single Piece/ One Piece Implants ,Two Piece Implants/ and the third type is Single stage implants. Each implant has its own pros and cons, advantages and disadvantages. 

There are 3 parts in a Dental Implant- Implant Fixture, Implant Abutment, and Implant crown. There are many disadvantages of Single Piece Implants but we place them in some limited cases where the load or stress is less, especially in the front teeth or Maxillary Lateral Incisors. Different doctors have different skill sets and are comfortable with the 3 different types of implants mentioned. We stopped doing Single Stage and Single Piece Implants because of various disadvantages. Single piece cementable implants have more disadvantages than advantages. The same problem is with 2 piece implants or single stage implants with cementable prosthetics. PLEASE NOTE: THE PROBLEM IS NOT WITH THE IMPLANT USED  THE PROBLEM IS WITH THE ABUTMENT USED WHICH ARE CEMENTABLE. WE STOPPED DOING CEMENTABLE BONE IMPLANT LEVEL ABUTMENTS BECAUSE OF VARIOUS COMPLICATIONS WHICH CAN OCCUR DURING THE COURSE OF YOUR LIFE.  Single Piece Implants come in various designs. Compressive, Basal, Disc etc. Most of the implantologists do single piece implants because its easier to do but its not the case. In a Single piece or One Piece Implant, the difference is that the Abutment and Implant fixture is one piece during the fabrication. THAT'S THE REASON WHY THE PROSTHETICS NEEDS TO BE CEMENTED WHICH WILL BECOME A NIGHTMARE TO REPAIR DURING ANY COMPLICATIONS. ANY IMPLANT BE IT SINGLE PIECE OR TWO PIECE IMPLANT WHEN PLACED IMPLANT IMMEDIATELY AFTER TOOTH EXTRACTION WE CAN EXPECT GINGIVA – GUM SHRINKAGE. THEY LOOK GOOD INITIALLY BUT THERE CAN DEVELOP A GAP BETWEEN THE GINGIVA AND THE CROWN WHICH CAN LEAD TO FOOD LODGEMENT AND LATER LEAD ESTHETIC AND HALITOSIS PROBLEMS. This problem can be solved with 2 piece implants only and not with single piece implants.  In a Two-Piece Implant the abutment and Implant fixture are separate and are connected with a screw. The major disadvantage of the conventional two-piece system is the screw loosening. The latest BIOLOCK  connection CAD CAM technology makes the two-piece implant into a one-piece implant by tightening the screw at 35 Newton Centimetre torque. We at The Dental Specialists use the advanced morse Biolock connection technology to convert the two-piece implants to One piece implants (No more Screw loosening as it used to happen in Conventional Two-Piece Implants).

At The Dental Specialists, we follow the unique advanced TTPHIL technique for most of our implants. The absence of a micro gap and micromovements between the implant and the prosthetic abutment (BIOLOCK connection technology) at the bone crest level offers TT PHIL implants many clinical and technical advantages like strong unibody design, no split parts,single-stage surgery with either  flapless approach and simple prosthetic technique.

The only advantage of single or one piece implant is that it reduces the cost of the abutment because it is manufactured in one piece. Hence it is cheaper when compared to a two-piece implant. There are too many disadvantages of single piece implants when compared to TTPHIL-ALL TILT™ Technique. The prosthetic options in Single piece implants or One-piece implants are very less. Hence the crown and bridges’ aesthetic quality is very poor. Single piece implants or One-piece implants cannot be placed in tilted fashion because they come with straight abutments. NOWADAYS THE SINGLE PIECE IMPLANTS ARE COMING WITH SCREW RETAINED PROSTHETICS SOLUTIONS. But again they are expensive. So most of the implantologists do not do screws. Ask for screw retained prosthetics if you wish to get single piece basal or Compressive Implants. This is a better option than single piece basal cementable abutments. 

Must read for those who want to undergo Single piece implants. 

15 reasons why we don’t use Single piece or One piece implants in all situations…

1. Abutments cannot be customised. The company  manufactures the abutment with an implant. Hence no customisation possible. The Single or one piece implants can only be bent around 15 degrees in compressive implants. It all depends again on the anchorage of the cortical plate. By placing a bicortical implant or implant apex engaging basal cortical bone doesn't mean you always get a very high torque which is predictable. These implants can never be made parallel to the adjacent implant abutment which is possible in the laboratory by CAD CAM abutment milling only. We used to do a lot of trimming and abutment shaping in the patient's mouth. This leads to a lot of titanium dusting which is not good if swallowed. Only Direct impressions (Impressions need to be taken directly) which will take up a lot of time keeping the patient's mouth open for a long time which is traumatic for the implant patient. If it's a full mouth case we have to do a lot of work on the chair side. This problem can be avoided in conventional Implants, where the Indirect Impressions (Customisation of the abutment is possible and is done in the laboratory reducing the chair side time)  can be taken, avoiding the patient to keep his mouth open for so long. Abutment milling done in the mouth and abutment milling done in the dental laboratory with the aid of CAD CAM ROBOTIC TECHNOLOGY (Computer Aided Designing, Computer Aided Machining) Which is precise according to you- Milling in the mouth or Milling in the laboratory? In single piece implants , you do have an option to take abutment level but the problem is in the lab they do parallelling of the implants based on the laboratory technician prosthesis we had to do trimming of the abutments in the patient's mouth. As a prosthodontist this is against the rules. We need to fabricate the crown based on the abutment not trim the abutment based on the crown fabricated. Anyways we have gone beyond the quackery job. Stopped doing this kind of job anymore.

TTPHIL Implants takes the advantage of fabricating the abutments and prosthesis with CAD CAM technology. Hence reducing the chair side time keeping the mouth open for so long, making the patient comfortable and less traumatic to the Implant Patient. TTPHIL implants utilises the 2 piece digital technology to fabricate the crowns. One of the most important criteria is to customise the abutment based on case to case which gives predictable esthetics and prevents food lodgement. Retrievability of the abutments from the implant solves most of the complications. 

2. After the implant placement the abutment milling has to be done directly in the mouth itself. There is no other option because the implant fixture and the abutment are connected which is why it is  called single piece or one piece implants. Sometimes in reduced interarch spaces if the implants are not milled immediately the abutments touch the opposing teeth not allowing the opposing arch to occlude, sometimes in full mouth cases the abutments are not parallel to each other, Hence to make the abutments parallel, they are milled in the mouth (As said in the first point, they can never be made parallel precisely compromising in the final outcome) Disadvantages of milling the abutment in the mouth 1)Milling in the mouth requires lot of chair side time keeping the implant patient’s mouth open for a very long time which is more traumatic to the patient. 2) This leads to a lot of titanium dusting which is not good if swallowed.  3) This leads to lot of stresses on the implant affecting the healing of the bone around the implant. 4) Abutment milling in Single piece implants is done with the airotor handpiece with Tungsten carbide burs which is not precise, Moreover leads to lot of frictional heat generation which is not good for bone healing around the implant or Osseointegration 5) Abutment milling in the mouth immediately after implant placement when the stability of the implant is not very good can lead to failure of the implant. Sometimes the implants can never be stable because of the quality of the bone. The bone may be very spongy. In such cases we do not get predictable primary stability. In such cases we have to load the implants forcefully because there is no choice.  Bone is something which is not in our or your hands. We need to respect bone biology and decide whether we can load or not to load in your mouth. Please be aware that in such cases loading the implants when there is no bone predictable primary stability just by splinting the implants will have chances of failures. In MPHIL or 2 piece implants we have at least an option to bury the implants which can have secondary healing- THE OSSEOINTEGRATION.  Once the secondary healing happens the implants become stable.

 

TTPHIL Implants at THE DENTAL SPECIALISTS take the advantage of fabricating the abutments and prosthesis with CAD CAM technology, hence reducing the chair side time keeping the mouth open for so long, making the patient comfortable and less traumatic to the Implant Patient.

3. In certain cases the bone availability and bone density may be less and bone thickness may be less, the implant stability in those cases is compromised or it may not be beyond 40 Newton Centimeter torque (which is the most essential factor for immediate loading). But we are forced to load the implant. Because it is a one piece system we cannot bury it also and keep it for bone integration or Osseointegration which is the most essential thing for long term success of the implant. Crestal Conventional Implants have the advantage of leaving the implant buried in the bone helping it for osseointegration. TTPHIL Implants has the advantage of both OSSEOFIXATION AND OSSEOINTEGRATION. We can at least bury the implant instead of losing the implant.

 

 

TTPHIL implants engage the basal cortical bone which is very strong and least resistant to resorption. The Tall and Tilted implants are the key factor for the success, Hence we at THE DENTAL SPECIALISTS are able to give immediate loading to our implants. We achieve very high torque beyond 80 Newton Centimeter which is strategic and key determinant factor for implant success. We engage all the strategic cortical basal bone which is highly mineralised and hence least resistant to resorption. The difference between the TTPHIL Implants and conventional Implants is that the Conventional Implants there is no bicortical anchorage, hence the stability achieved in most of the cases is less than 40 Newton Centimetre. Even if the conventional Implants achieve high torque during the Implant Insertion, the apical tip of the cortical bone rests in the soft trabecular bone, which is least resistant to resorption. This bone is very soft which helps only for the blood and nutritional supply. TTPHIL Implants engage the Bicortical Basal at the Strategic locations to achieve a very high torque beyond 70 NC, at the same time able to deliver high and precise prosthetic solutions with CAD CAM Zirconia and DMLS CAD CERAMIC CROWNS AND BRIDGES which is screw retained. (This point is discussed in detail in POINT 14)

4. Monobloc implants are very thin when compared to two piece  Conventional implants. In the above picture you can see the different implant types. Why does the company have to manufacture two piece implants when single piece implants can be done in all the cases. For example, when most of the time 6 implants or sometimes 8 implants are placed to replace the upper full mouth complete edentulous jaw (When all teeth are missing in the upper jaw), why do we need to place more implants.

Imagine the surface area of the implants when compared to Single or One piece conical Implants. The TTPHIL Implants almost have double the surface area when compared to one piece implants. Hence 6 implants in most of the cases are sufficient. Why do you need to give more money when there is no advantage of placing more implants? Usually in the molar region when one implant is sufficient the single implant specialists use two implants which is not required in all the cases unless the edentulous space is more. The single piece implants are core conical, thin and engage the apical cortical bone, they need to be splinted. Hence the place 2 implants instead of one. Approximately 10- 12 single implants are placed for the upper jaw. The more implants – More expensive it is. Think about it! 

 

5. Less Surface area- Conical Implants- Smooth Surface Implants- More Implants Required- More Money- More Investment. Since these implants are thin we need to place more implants. For example In a full mouth rehabilitation in the upper jaw, 6 implants are sufficient to hold the bridge of 14-16 teeth depending on case. The same thing when we use single piece implants we need to place a minimum of 10 to 12 implants.

6. Single piece or One Piece Implant abutments will not have a finish margin. There can never be a precise finish margin since the abutment is already thin; we cannot refine it more in the patient's mouth. Moreover it will not be done in the laboratory for precise finish margins. Any abutment done outside the mouth we can clearly define the finish margins according to gum levels in individuals.

7. Since the abutment is thin the crown fabricated will have overhanging margins. This will be a big problem when we restore single piece implants in the back region of the jaw. This leads to a lot of food lodgement over a period of years. It is impossible to clean and maintain oral hygiene in these cases.

8. No CAD CAM software can be detected for single piece implants. The crowns have to be done manually. Precision fit can never be given in these implant cases

9. We need to take direct impressions with Alginate or polyether or polyvinyl siloxane impression materials. In all cases we cannot take the impressions with Polyvinyl Siloxane (PVS) or polyether impression material which is more precise because they are rigid impression materials. In case the impression is taken with PVS impression material after the impression is poured with Die stone the cast breaks because the implant abutments are very thin. Precision is a factor when a direct impression is taken for fabrication of the crowns. Now some single piece implantologists use disposable transfers to avoid the breakage of the abutments in the cast. But to make them parallel the laboratory technician does a lot of modifications in the laboratory. This will make the patient again open their mouth for a long time , giving a traumatic experience to the patient. The doctor needs to modify the implants according to the technician who fabricated the prosthesis. In Screw retained technology the technician does according to the doctor’s impressions taking the help of CAD CAM SOFTWARE, which is highly precise.Nothing can go wrong here unless the doctor doesn’t take the impressions properly. The Implant specialist needs to be a Prosthodontist or a very good trained dentist to get precise Screw Retained Prosthetic Solutions- SRPS (Crown and Bridge or Bar  supported fixed hybrid dentures or Malo Bridge)  Food lodgement is the most important factor to be considered going for single piece implants. Usually to avoid food lodgement the single piece implantologists recommend supra gingival finish line and space between the crown and bridge and the bone. They consider this as an advantage but for the patient always the patient feels that there is space between the prosthesis and the gums. Most of the patients complain that their tongue goes between the prosthesis and the gum which is very very Irritating, Moreover there is speech problem because of the gap. They complain that the pronunciation is not like before leading to compromised life.

10. The abutment for a single piece is the same for both front or back teeth cases. Back teeth we need a wide abutment to prevent over hangings and optimum porcelain thickness to prevent ceramic chipping.

11. Sub gingival finish margins are not possible in Single Piece or One Piece Implants. When we open the flap and a flapless technique is not possible in certain cases where bone availability is less, and ridge splitting is indicated these implants are not suggested.

12. Single piece implants are not suggested when the bone density is less which can be diagnosed with the Xray and Hounsfield units. In these cases we will not be able to achieve good torque ( 4oNC) beyond. Still the implant is exposed to the oral environment leading to stresses on the Implant from Day 1, which can lead to an implant failure.

13. Single piece implants are not possible when we use TTPHIL ALL TIL™ Technique,also ALL ON 4 implants technique. New concepts show that the tilted implants taking Bi cortical encourage , the implants can be loaded immediately.

14. Screw retained option is not possible. If any complication or food lodgement occurs in  Single Piece  implants, then the only option is to cut the crowns because they are cemented. Check the video below.

15. The crowns or bridges in Single Piece implants have to be cemented. This cement gets entrapped between the gums leading to bone loss and gum irritation. Whatever cement is used radiopaque or Radiolucent cements it is impossible to remove the complete implant residue below the crown and bridge, which goes into the gums. Cement retained prosthetic Solutions have a disadvantage that the implants are all connected to each other. If one of the implants is rejected and pain starts and is mobile( moving) , the whole bridge needs to be cut. This is the most traumatic experience for the doctor and the patient. Patient needs to open his or her mouth for so long to cut the bridge. Cutting the bridge is not so easy when compared to cutting the tooth. The airotor handpiece which rotates at 200000 RPM (Rotations per Minute) needs to cut the metal which should be done very carefully without injuring the cheeks, lips and tongue. Screw retained prosthetics avoids this hazard. As a patient one should be prepared. Both Single piece and conventional Implants can fail. Servicing is easy in  conventional Implants because they are screw retained which is not possible in Single Piece Implants.