High Technology in Implant Dentistry: Part 1

The final restorative treatment of implant dentistry has significant consequences when the teeth involved are located in the aesthetic zone. Not only does the final restoration have to be functionally sound, but it also has to be acceptable in the way it appears. Today’s population wants treatment now! With the advent of technology in dentistry such as computed tomography (CT) scans and lasers, the patient’s requests and aesthetic goals are much easier to accomplish.
The immediate placement of dental implants (with tooth extraction) is an approach that has become more popular in recent years. This approach is used successfully, according to the Immediate Function Consensus Conference (November 7, 2003, 52nd Annual Meeting of the American Academy of Implant Dentistry, Hollywood, Fla). The terminology was established, and suggested guidelines for teeth/tooth replacement were made.¹ Concerns do exist when the extraction presents with an active infection because of periodontal, endodontic, or root fracture associated lesions. Furthermore, the possibility also exists for a residual infection in the extraction area that could compromise immediately placed implant osseointegration.  The use of a YSGG laser to detoxify the osteotomy site (eg, use of lasers in endodontics) has diminished this problem.²
The use of CT scan technology as a tool for diagnosing and treatment planning dental implants has allowed for a more accurate understanding of the tooth-to-bone anatomical relationship. In recent years, it has provided us the opportunity to use true 3-dimensional reconstructions and stereolithographic models for improved presurgical prosthetic planning.³ Such reconstructions and models can be created from CT scans with the use of  the SimPlant Planner (Materialise). This program helps the dentist to accurately measure distances, angles, and density, resulting in precise implant placement. SimPlant allows manipulation of the gray scale presentation to help locate various anatomical structures, such as the hard-to-find inferior alveolar canal. Also, with the software one can visualize implants and abutments that are planned for placement. The position and orientation of implants can be altered interactively in the 3-dimensional view. One final helpful tool is the ability to determine the quality of bone in which one plans to place the implants.
The Er,Cr:YSGG laser (Biolase Technology) has assisted in speeding healing time, decreasing postoperative pain, and increasing bone-to-implant contact.⁴ Since Maimon developed the ruby laser in 1960,⁵ lasers have slowly been incorporated into the dental world. Today, they have FDA approval for cutting bone, enamel, dentin, and soft tissue. For implant dentistry, lasers can be used to cut flap preparations, detoxify the osteotomy site, start regional acceleratory phenomenon (RAP), ^6-9 weld tissue, accelerate angiogenesis, and promote biostimulation to help to repair damaged cells while reducing pain.^10-13
The purpose of this article is to present 2 cases: (1) immediate load and (2) a 2-stage approach. These cases utilize CT technology to achieve exact implant placement, along with a YSGG laser to accomplish faster healing, less tissue shrinkage, and increased bone-to-implant contact. This allows the dentist/lab technician to develop a custom post and crown and to deliver treatment with greater aesthetics, quicker case completion, and most importantly, reduced postoperative discomfort. Part 1 of this article presents the immediate load case. The case with a 2-stage approach will be presented in Part 2.

CASE REPORT NO. 1

Figure 1. Patient presents with loosening and discoloration of tooth No. 7.	Figure 2. CT scan is reformatted for use with SimPlant software.

A 52-year-old male presented to the office for evaluation of tooth No. 7 for replacement with a dental implant. The patientís main complaint was loosening of the tooth and discoloration of the coronal portion (Figure 1). Upon clinical observation, palatal swelling with mid palatal bone loss was found. This was associated with a vertical fracture of the root. A pocket of 8 mm in the mid lingual aspect was also found upon probing. Bleeding occurred during probing, and suppuration originating from the pocket area occurred as a result of digital pressure applied to the gingival tissues.
There were no significant medical problems noted on the patient’s health history. The patientís dental history presented with numerous alloy restorations in posterior teeth, crowns on teeth Nos. 8, 19, and 30, as well as root canal treatment of teeth Nos. 7 and 8. The patient was also missing teeth Nos. 1, 16, 17, and 32. There was no soreness in the muscles of mastication or any history of TMD problems. The toothís history indicated RCT therapy 6 years prior to the exam. The dental records obtained included a periapical x-ray of tooth No. 7, a panorex film, and upper and lower impressions for SurgiGuide (Materialise) creation.  A CT scan was completed at the time the patient presented to our office; this was reformatted for use with the SimPlant software (Figure 2). From the SimPlant program, infection was identified on the lingual/apical portion of the tooth (approximately 2.5 by 5.5 mm). Hounsfield values were in the 1,000 range, adequate for immediate load. The width of the tooth was 4.5 mm, and the depth of the tooth was 5.5 mm. Thus, it was determined that a Nobel Biocare Nobel Replace Tapered Groovy 5.0 x 13.0-mm length would be the implant of choice. The case was treatment planned on the computer using the SimPlant Planner and e-mailed to Materialise for fabrication of the Surgi-Guide. After being informed about the pros and cons of every option, the patient opted for an implant-supported crown.

SURGICAL PHASE FOR THE PLACEMENT OF AN IMPLANT IN POSITION NO. 7

The patient rinsed with Peridex (Zila) for 30 seconds, and then IV sedation was performed to produce a mildly sleepy state. The drugs given were Versed, Nubain, and Benadryl. On completion of the sedation, dexamethasone and cefazolin were used. Local anesthetic of 20 mg of lidocaine with 10 mcg of epinephrine and 5 mg of Marcaine with 5 mcg of epinephrine were used as well. The tooth was removed with the aid of periotomes and forceps, without damaging tissue and surrounding bone (Figures 3 to 5). Upon removal of the tooth, the fracture lingual to the apex of the tooth was found, as the SimPlant study had shown.

Figure 6. SurgiGuide with 3.5-mm-diameter ring and internally irrigated drill is used, followed by 4.3-mm-diameter and 5.5-mm-diameter rings and drills.	Figure 7. Laser tip is initiated at apex of the osteotomy site, then moved coronally in counterclockwise pattern.
Figure 8. The implant is tested at 35N of reverse torque.	Figure 9. Impression post is seated and verified radiographically.

The SurgiGuide with a 3.5-mm-diameter ring was seated, and an internally irrigated drill that corresponds to the ring was used. This was followed by a 4.3-mm-diameter ring and drill in the same fashion (Figure 6). Finally, the 5.0-mm-diameter ring and drill were used. The osteotomy was assessed with a curette to determine if any fibrous tissue remained after the osteotomy cuts had been completed. Feeling no fibrous tissue, a YSGG laser was used as reported by Kusek. Periotest values increased by 40% when lased areas were compared to nonlased areas.¹⁴ These results were achieved by a single use with a setting of 0.5 W 20 Hz 3/8 used in such a way that the laser tip was initiated at the apex of the osteotomy site and then moved up coronally in a counterclockwise pattern (Figure 7). Using this technique appears to start the RAP to increase the amount of fibroblasts forming in the area, thus affecting the increased Periotest values. This procedure not only detoxifies the site but increases fibroblast attachment to the implant. As stated by Misch,¹⁵ “the amount of implant-bone contact is directly related to the density of bone. Consequently, less dense bone compared to dense bone requires greater implant surface area to obtain the same amount of implant-bone contact. Therefore, with less bone contacting the implant body, the overall stress will increase.” Thus, numerous companies have changed the shapes of implants and have added a roughened surface. The author is suggesting that a D-4 bone can be changed to D-3 or even to D-2. This allows more biomechanical stress in the bone, which will ultimately increase success rates.
The implant was seated 3 mm below the gingival crest.¹⁶ No grafting needed to be performed due to the close adaptation of the osteotomy and the socket site. The implant was tested to see if it could withstand 35N of reverse torque; it was able to withstand the force, allowing for immediate load (Figure 8). An impression post was seated and then verified using a radiograph to ensure that it had a tight adaptation to the implant body (Figure 9). A custom tray was utilized and filled with Aquasil impression material (DENTSPLY; Figures 10 and 11). Blu-Mousse impression material (Parkell) was used for a bite registration. The temporary post was then seated and fabricated to fit into space No. 7 (Figure 12). This was followed by tissue welding, performed with the use of a YSGG laser at 0.5 W 20 Hz 0/12 setting (Figure 13). A polycarbonic temporary crown was then fabricated and seated (Figure 14). Finally, after sedation had been completed, a face-bow was acquired using the Panadent system (Figure 15).

The laboratory partner was Americus Dental Laboratory in New York, which completed a custom post with the facial margin 1 mm from the base of the implant (Figure 16). The crown was also completed, developing emergence in accordance with the wishes of the laboratory and doctor (Figure 17). Because the gingival tissue would only shrink by approximately 0.5 mm, the crown could be confidently planned to match the contralateral position. Advantages of the laser used with soft tissues are as follows: reduction in bleeding, postoperative pain, swelling, and edema. It also aids in precise coagulation and cutting. There are also advantages to using the laser to cut bone: gentler than bone saws or high-speed drills, less postoperative pain and swelling, less necrosis of surrounding tissue, minimal trauma due to heat transfer, and no trauma to the periosteum when removing bone for grafting. The use of lasers in endodontics for disinfection properties gives the clinician the confidence to complete the case with the lab before ìosseointegrationî has been completed.

Figure 12. Temporary post is seated and fabricated to fit space No. 7.	Figure 13. Tissue welding using the YSGG laser.
Figure 14. Polycarbonic temporary crown is fabricated and seated.	Figure 15. Face-bow is acquired using the Panadent system.
Figure 16. Laboratory completes custom post with facial margin 1 mm from base of implant.	Figure 17. Crown is completed with proper emergence.
Figure 18. Biostimulation is accomplished 3 times within a 2-week period.	Figure 19. Four days postoperative.

Figure 20. Note tissue adaptation on completion of the case.

Biostimulation (LaserSmile [Biolase Technology]) was done in the area 3 times within a 2-week period (Figure 18). Using biostimulation allows cells to repair themselves quickly and reduce histamine release. Biostimulation energizes the mitochondria within the cells to produce this effect.¹⁷ The patient rated the pain index for this surgery at a 1 on a scale from 0 to 10 (with 10 being the most severe pain ever experienced). In fact, the patient stated that he only took his initial pain analgesic and did not need any other pain medication. Figure 19 is a 4-day postoperative photo, and Figure 20 is the final prosthesis at 3 months.
The case was completed within 3 months, when the temporary crown and post were simply removed and the permanent post and crown were seated. Note Figure 20 and the tissue adaptation on completion of the case.

Acknowledgment

The author thanks his staff for their assistance and encouragement, and his patients, who share his enthusiasm for these new techniques.

References

1. Misch CE, Hahn J, Judy KW, et al; for the Immediate Function Consensus Conference. Workshop guidelines on immediate loading in implant dentistry. November 7, 2003. J Oral Implantol. 2004;30:283-288.
2. Matsumoto K. Lasers in endodontics. Dent Clin North Am. 2000;44:889-906.
3. Ganz SD. The reality of anatomy and the triangle of bone. Inside Dentistry. 2006;6:72-77. Available at: http://www.drganz.com/insidedentistryfinal.pdf. Accessed February 12, 2007.
4. Rizoiu IM, Eversole LR, Kimmel AI. Effects of an erbium, chromium: yttrium, scandium, gallium, garnet laser on mucocutaneous soft tissues. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 1996;82:386-395.
5. Maiman TH. Stimulated optical radiation in ruby. Nature. 1960;187:493-494. Available at: http://www.nature.com/nature/journal/v187/n4736/pdf/187493a0.pdf. Accessed February 12, 2007.
6. Frost HM. The biology of fracture healing: an overview for clinicians. Part I. Clin Orthop Relat Res. 1989;248:283-293.
7. Frost HM. The biology of fracture healing: an overview for clinicians. Part II. Clin Orthop Relat Res. 1989;248:294-309.
8. Frost HM. The regional acceleratory phenomenon: a review. Henry Ford Hosp Med J. 1983;31:3-9.
9. Shih MS, Norrdin RW. Regional acceleration of remodeling during healing of bone defects in beagles of various ages. Bone. 1985;6:377-379.
10. Pinheiro AL, Pozza DH, Oliveira MG, et al. Polarized light (400-2000 nm) and non-ablative laser (685 nm): a description of the wound healing process using immunohistochemical analysis. Photomed Laser Surg. 2005;23:485-492.
11. Trelles MA, Mayayo E. Bone fracture consolidates faster with low-power laser. Lasers Surg Med. 1987;7:36-45.
12. Takeda Y. Irradiation effect of low-energy laser on alveolar bone after tooth extraction: experimental study in rats. Int J Oral Maxillofac Surg. 1988;17:388-391.
13. Dˆrtbudak O, Haas R, Mallath-Pokorny G. Biostimulation of bone marrow cells with a diode soft laser. Clin Oral Implant Res. 2000;11:540-545.
14. Kusek ER. Use of the YSGG laser in dental implant surgery: scientific rationale and case reports. Dent Today. Oct 2006;25:98-103.
15. Misch CE. Consideration of biomechanical stress in treatment with dental implants. Dent Today. May 2006; 25:80-85.
16. Tarnow DP, Eskow RN. Preservation of implant esthetics: soft tissue and restorative considerations. J Esthet Dent. 1996;8:12-19.
17. Hamajima S, Hiratsuka K, et al. Effects of low-level laser irradiation on osteoglycin gene expression in osteoblasts. Lasers Med Sci. 2003;18:78-82.

Dr. Kusek is a 1984 graduate of the University of Nebraska School of Dentistry. He has been a general dentist for more than 22 years in Sioux Falls, SD. He is a Diplomate of the American Board of Oral Implantology/Implant Dentistry and the International Congress of Oral Implantologists, a Fellow of the American Academy of Implant Dentistry, and has earned Mastership in the World Clinical Laser Institute and the AGD. He is adjunct professor at the University of South Dakota and lectures nationally on YSGG lasers. He can be reached at (605) 371-3443 or implantdental@midconetwork.com.

Disclosure: The author has no financial interest in Biolase or funding from the manufacturer for research studies.