How a Single Dental Implant Is Planned From a 3D Scan

By Dr. Nojan Jahedmanesh, DDS · Reviewed by Dr. Masih Rezaei, DDS · Published September 23, 2026 · Implants · 7 minute read · More articles

A single dental implant is planned backwards. We decide where the crown needs to sit first. Then the titanium fixture is positioned on a 3D cone beam scan to support that crown. Then a surgical guide carries the position into your mouth. This article walks through what the scan shows, the measurements that decide the plan, and what happens between the scan and the finished tooth at Pearl32 Dentistry and Wellness in Laguna Hills. For the treatment itself, see our single dental implants page.

What does the 3D scan show that an x-ray does not?

Width. A flat x-ray shows the height of the bone and nothing about its thickness. The cone beam scan shows the bone from cheek to tongue, in millimeters, on every slice. That one measurement decides whether a fixture fits without a graft.

The scan also shows the path of the nerve canal in the lower jaw. It shows the floor of the sinus above the upper back teeth. Both have to be avoided, and both are invisible in depth on a flat image.

The scan itself takes under a minute. You sit or stand while the arm rotates once around your head, and nothing encloses you. The images are on the screen in the operatory within a few minutes and we go through them with you, slice by slice. Our 3D CBCT imaging page covers dose and what the scan will not show.

Why the crown is planned before the implant

An implant placed where the bone happens to be, rather than where the tooth needs to be, gives a crown that is tilted, too long or hard to clean. So the order at Pearl32 is crown first.

We take a digital intraoral scan of your teeth. No impression trays. On the computer the missing tooth is drawn in at the size and angle that matches its neighbors and meets the tooth in the opposite jaw. Then the fixture is placed on the cone beam scan underneath that crown. If the two do not line up, the plan changes now, on the screen, rather than in the chair.

The numbers that decide the plan

A few measurements settle most single implant plans. They are planning rules, not promises, and they are why the scan matters.

• Bone width. A standard fixture is roughly 4 mm across. It needs about 1 mm of bone on the cheek side and on the tongue side, so a ridge close to 6 mm wide is the usual working minimum. A narrower ridge means a narrower fixture or a graft.
• Bone height. Most fixtures are 8 to 13 mm long. In the lower jaw we keep a safety margin of about 2 mm above the nerve canal. In the upper back jaw the sinus floor sets the limit.
• Distance to the neighbors. About 1.5 mm from the root of the tooth on either side, so their bone and blood supply are left alone.
• Bone density. The scan shows whether the bone is dense or soft. That changes how the site is prepared and how long we wait before the crown goes on.

When the scan shows a shortfall, the plan says so in writing. A small defect is grafted at the same visit as the implant. A larger one is grafted first and left three to six months to heal. Our bone grafting page explains socket grafts, ridge grafts and sinus lifts.

What the surgical guide does

Once the fixture position is agreed on the screen, the plan becomes a surgical guide. It is a thin printed or milled template that seats over your teeth, with a metal sleeve where the implant goes. On the day, the drill passes through the sleeve. Depth, angle and position follow the plan rather than the hand alone.

A guide narrows the margin of error but does not remove it. Khaohoen and colleagues, writing in BMC Oral Health in 2024, reported mean deviations for guided placement of 1.11 mm at the implant head, 1.40 mm at the tip and 3.51 degrees of angle. We build that margin into the plan. It is one reason the 2 mm nerve margin exists.

From the scan to the finished tooth

1. Consultation and scan. Plan on about an hour. You leave with the plan in writing, itemized, with the stages and the timing.
2. Placement. 45 to 90 minutes under local anesthetic. Sedation is available if you want it, in which case bring a driver.
3. Healing. The fixture bonds to the bone over three to four months in the lower jaw and four to six in the upper. For a front tooth we arrange a temporary so you are not without a tooth.
4. The crown. We scan the healed fixture, design the crown and mill it on the CAD/CAM unit in our own office. It is often fitted in one visit. Some cases need laboratory-made parts.

With enough bone at the site, allow 16 to 28 weeks from consultation to finished tooth. If a graft or sinus lift comes first, nine to twelve months is realistic. These are typical ranges rather than promises.

Missing every tooth in a jaw is a different plan, with different daily trade-offs. Our article on what daily life is like with All-on-4 or dentures covers that. If you are weighing an implant against a bridge for one tooth, our implant versus bridge comparison sets the two side by side.

Questions people ask

Do I need a 3D scan for one dental implant?

For nearly every one, yes. The scan shows bone width and the distance to the nerve canal or sinus floor, and neither is measurable on a flat x-ray. It also lets us position the fixture for the crown rather than only for the bone. If you had a scan elsewhere within the last twelve months, bring the raw data file and we can often use it.

Is a cone beam scan safe?

The dose is low compared with a medical CT of the same area, and higher than a single dental x-ray. We scan the smallest field that answers the question and only when the images will change the plan. Tell us if you are or may be pregnant.

Can I see the implant plan before I decide?

Yes. You look at the scan with us, slice by slice, and see the fixture positioned under the planned crown before anything is booked. The itemized estimate comes in writing at the same visit, with optional items marked as optional.

What if the scan shows there is not enough bone?

Then the plan includes a graft, and says so. A small defect is grafted when the implant is placed. A larger one is grafted first and left three to six months. In the upper back jaw a sinus lift adds height beneath the sinus floor. The scan tells us which applies before anything starts.

This article is general information, not a diagnosis. What is right for you can only be decided after an examination.