Editor’s intro: Dr. Cary A. Shapoff illustrates several cases using Laser-Lok microchannel technology to preserve crestal bone and soft tissue esthetics.
Dr. Cary A. Shapoff shares patient cases involving a surface treatment shown to attract a true, physical connective tissue attachment
Numerous published animal and human dental implant studies report crestal bone loss from the time of placement of the healing abutment to various time periods after restoration. The bone loss can result in loss of interproximal papilla and recession of crown margins. These case examples demonstrate the long-term results that can be obtained utilizing a variety of implant and abutment styles and sizes with the Laser-Lok® (BioHorizons®) microchannel collar design to preserve crestal bone and soft tissue esthetics. Case 1 involved extraction, socket grafting, 6-month delayed implant placement, and final restoration in 6 months. This case was the first reported use of laser-microchannel technology (Laser-Lok) and justified the continued use and documentation of numerous other case examples in a private practice setting.
Case 1 (Figures 1-5)
First reported use of a Laser-Lok implant
A 34-year-old female presented with external resorption at the level of the cementoenamel junction (CEJ) of tooth No. 9. Various treatment options were presented, and the patient elected extraction and dental implant placement. After atraumatic extraction, the socket anatomy did not allow for immediate placement with acceptable initial stability. The socket was grafted with allograft calcified bone and allowed to heal for 6 months. At that time, a dental implant with a 1 mm Laser-Lok microchannel collar design was placed. A subepithelial connective tissue graft was also utilized on the adjacent tooth No. 10 for root coverage. Six months after placement, second-stage surgery was performed, and the tooth was restored with a customized abutment and PFM crown. Note the maintenance of excellent crestal bone levels on the Laser-Lok microchannel collar (within 0.5 mm of the implant/abutment interface) at 19 years post-restoration. The soft tissue margins have remained stable and exhibit excellent periodontal health.
Case 2 (Figures 6-10)
A 45-year old female presented with non-restorable caries under existing crown on tooth No. 7. Treatment decision: Single tooth implant — immediate extraction, immediate placement with provisional loading utilizing BioHorizons Plus (platform-switched) implant (4.6 x 12 mm with 3.5 mm platform).
Case 3 (Figures 11-14)
Two adjacent BioHorizons Laser-Lok dental implants (4.6 mm x 12 mm)
A 52-year-old female patient presented with maxillary central incisors that were deemed non-restorable and replacements with dental implant restorations selected after discussing restorative options.
Cases 4 and 5 (Figures 15-23)
Clinical use of laser-microtextured CAD-CAM abutments
Laser-Lok microchannels are a proprietary dental implant surface treatment developed from over 25 years of research, initiated to create the optimal implant surface. Through this research, the unique Laser-Lok surface has been shown to elicit a biologic response that includes the inhibition of epithelial downgrowth and the attachment of connective tissue.2-10 This physical attachment produces a biologic seal around the implant that protects and maintains crestal bone health. The Laser-Lok phenomenon has been shown in post-market studies to be more effective than other implant designs in reducing bone loss.11,12,13,14,27
Unique surface characteristics
Laser-Lok microchannels are a series of cell-sized circumferential channels that are precisely created using proprietary laser ablation technology. This technology produces extremely consistent microchannels that are optimally sized to attach and organize both osteoblasts and fibroblasts.15-25 The Laser-Lok microstructure also includes a repeating nanostructure that maximizes surface area and enables cell pseudopodia and collagen microfibrils to interdigitate with the Laser- Lok surface.
Different from other surface treatments
Virtually all dental implant surfaces on the market are grit-blasted and/or acid-etched. These manufacturing methods create random surfaces that vary from point to point on the implant and alter cell reaction depending on where each cell comes in contact with the surface.10 While random surfaces have shown higher osseointegration than machined surfaces,11,26 only the Laser-Lok surface has been shown using light microscopy, polarized light microscopy, non-human and human histologic specimens, and scanning electron microscopy to also be effective for inhibiting epithelial downgrowth and formation of connective tissue attachment.2-10
The clinical advantage
The Laser-Lok surface has been shown in several studies to offer a clinical advantage over other implant designs. In a prospective, controlled multi-center study, Laser-Lok implants, when placed alongside identical implants with a traditional surface, were shown at 37 months post-op to reduce bone loss by 70% (or 1.35 mm).11 In a retrospective, private practice study, Laser-Lok implants placed in a variety of site conditions and followed up to 3 years minimized bone loss to 0.46 mm.12 In a prospective, University-based overdenture study, Laser-Lok implants reduced bone loss by 63% versus NobelReplace™ Select.13
The establishment of a physical, connective tissue attachment to the Laser-Lok surface has generated an entirely new area of research and development: Laser-Lok applied to abutments. This provides an opportunity to use Laser-Lok abutments to create a biologic seal and Laser-Lok implants to establish superior osseointegration15 — a solution that offers the best of both worlds. Alternatively, Laser-Lok abutments can support peri-implant health around implants without Laser-Lok. Multiple pre-clinical and clinical studies support both concepts.5-9 Laser-Lok abutments can inhibit epithelial downgrowth — physically attach connective tissue to protect and maintain crestal bone. Most recently, the combination of Laser-Lok abutments, implants, and platform switching was shown to regenerate crestal bone surrounding the implant.5 Cases 4 and 5 demonstrate the use of the Ti-base laser-microtextured abutments with the titanium base and the custom zirconia core abutment. These cases have maintained exceptional crestal bone and excellent soft tissue contours during the 5-year follow-up period.
Restorations for cases 1 and 4 by Jeffrey A. Babushkin, DDS (Trumbull, Connecticut). Restorations for cases 2 and 5 by David J. Wohl DDS, (Fairfield, Connecticut). Restorations for case 3 by Jeffery D. O’Connell, DMD (Fairfield, Connecticut).
Before his microchannel technology experiences, Dr. Cary Shapoff wrote about treating compromised sites with narrow implants. Read his article here.
- Implant success rate is the weighted average of all published human studies on BioHorizons implants. These studies are available for review in BioHorizons document number ML0130.
- Nevins M, Nevins ML, Camelo M, Boyesen JL, Kim DM. Human histologic evidence of a connective tissue attachment to a dental implant. Int J Periodontics Restorative Dent. 2008;28(2):111-121.
- Weiner S, Simon J, Ehrenberg DS, Zweig B, Ricci JL. The effects of laser microtextured collars upon crestal bone levels of dental implants. Implant Dent. 2008;17(2):217-228.
- Shin SY, Han DH. Influence of a microgrooved collar design on soft and hard tissue healing of immediate implantation in fresh extraction sites in dogs. Clin Oral Implantsl Res. 2010;21(8):804-814.
- Nevins M, Nevins ML, Gobbato L, et al. Maintaining interimplant crestal bone height via a combined platform-switched, Laser-Lok implant/abutment system: a proof-of-principle canine study. Int J Periodontics Restorative Dent. 2013;33(3):261-267.
- Nevins M, Kim DM, Jun SH, et al. Histologic evidence of a connective tissue attachment to laser microgrooved abutments: a canine study. Int J Periodontics Restorative Dent. 2010;30(3):245-255.
- Geurs NC, Vassilopoulos PJ, Reddy MS. Histologic evidence of connective tissue integration on laser microgrooved abutments in humans. Clin Adv Periodontics. 2011;1(1):29-33.
- Nevins M, Camelo M, Nevins ML, Schupbach P, Kim DM. Connective tissue attachment to laser microgrooved abutments: a human histologic case report. Int J Periodontics Restorative Dent. 2012;32(4):385-392.
- Nevins M, Camelo M, Nevins ML, Schupbach P, Kim DM. Reattachment of the connective tissue fibers to the laser-microgrooved abutment surface. Int J Periodontics Restorative Dent. 2012;32(4):e131-e134.
- Iglhaut G, Becker K, Golubovic V, Schliephake H, Mihatovic I. The impact of dis-/reconnection of laser microgrooved and machined implant abutments on soft- and hard-tissue healing. Clin Oral Implants Res. 2013;24(4):391-397.
- Pecora GE, Ceccarelli R, Bonelli M, Alexander H, Ricci JL. Clinical evaluation of laser microtexturing for soft tissue and bone attachment to dental implants. Implant Dent. 2009;18(1):57-66.
- Shapoff CA, Lahey B, Wasserlauf PA, Kim DM. Radiographic analysis of crestal bone levels on Laser-Lok collar dental implants. Int J Periodontics Restorative Dent. 2010;30(2):129-137.
- Botos S, Yousef H, Zweig B, Flinton R, Weiner S. The effects of laser microtexturing of the dental implant collar on crestal bone levels and peri-implant health. Int J Oral Maxillofac Implants. 2011;26(3):492-498.
- Bae HEK, Chung MK, Cha IH, Han DH. Marginal tissue response to different implant neck design. J Korean Acad Prosthodont. 2008;46(6):602-609.
- Frenkel SR, Simon J, Alexander H, Dennis M, Ricci JL. Osseointegration on metallic implant surfaces: effects of microgeometry and growth factor treatment. J Biomed Mater Res. 2002;63(6):706-713.
- Ricci JL, Grew JC, Alexander H. Connective-tissue responses to defined biomaterial surfaces. I. Growth of rat fibroblast and bone marrow cell colonies on microgrooved substrates. J Biomed Mater Res A. 2008;85(2):313-325.
- Grew JC, Ricci JL, Alexander H. Connective-tissue responses to defined biomaterial surfaces. II. Behavior of rat and mouse fibroblasts cultured on microgrooved substrates. J Biomed Mater Res A. 2008;85(2):326-335.
- Soboyejo WO, Nemetski B, Allameh S, et al. Interactions between MC3T3-E1 cells and textured Ti6Al4V surfaces. J Biomed Mater Res. 2002;62(1):56-72.
- Ricci J, Charvet J, Frenkel SR, et al. Bone response to laser microtextured surfaces. In Davies JE, ed. Bone Engineering. Toronto, Canada: Em2 Inc.; 2000.
- JC Grew, JL Ricci. Cytoskeletal organization in three fibroblast variants cultured on micropatterned surfaces. Presented at the Sixth World Biomaterials Congress. May 15-20, 2000; Kamuela, HI.
- JC Grew, SR Frenkel, E Goldwyn, T Herman, JL Ricci. Cytological characteristics of 3T3 fibroblasts cultured on micropatterned substrates. Presented at the 24th Annual Meeting of the Society for Biomaterials. April 22-26, 1998; San Diego, CA.
- JC Grew, JL Ricci, AH Teitelbaum, JL Charvet. Effects of surface microgeometry on fibroblast shape and cytoskeleton. Presented at the 23rd Annual Meeting of the Society for Biomaterials. April 30-May 4, 1997; New Orleans, LA.
- Ricci JL, Rose R, Charvet JK, Alexander H, Naiman CS. Cell interaction with microtextured surfaces. Presented at the Fifth World Biomaterials Congress. May 29-June 2, 1996; Toronto, Canada.
- Ricci JL, Charvet JK, Sealey R, et al. In vitro effects of surface roughness and controlled surface microgeometry on fibrous tissue cell colonization. Presented at the 21st Annual Meeting of the Society for Biomaterials. March 18-22, 1995; San Francisco, CA.
- Boyan BD, Schwartz Z. Surface topography modulates osteoblast morphology. In Davies JE, ed. Bone Engineering. Toronto, Canada: Em2 Inc.; 2000.
- Wennerberg A, Albrektsson T. Effects of titanium surface topography on bone integration: a systematic review. Clin Oral Implants Res. 2009;20(suppl 4):172-184.
- Nevins M, Leziy S, Kerr E, Janke U, et al. A Prospective Clinical and Radiographic Assessment of Platform-Switched Laser-Microchannel Implants Placed in Limited Interimplant Spaces. Int J Periodontics Restorative Dent. 2017;37(1):33-38.