Biologic Width Demystified
Richard Erickson, MS, DDS
Much fuss is justifiably made by many clinician speakers over violating the biologic width in crown margin placement. We've all seen seminar slides of chronically inflamed tissue around a crown in violation of this sacred region. But what exactly is this so-called biologic width? Why when despite your best efforts to esthetically hide a crown margin in the sulcus, it comes peeking back at you at the next prophy visit? John Kois answered these questions recently1 much more clearly than I have ever heard in a presentation and here are the highlights.
Some healthy dimensions of the gingival area are needed in order to compare to what is abnormal. As you can see on the diagram at left, a kind of symmetry exists in normal healthy gingiva: 1mm sulcular depth, 1mm attached epithelium and 1mm connective tissue before the crest of the bone is reached. This is the biologic width. 85% of healthy patients will exhibit this 3mm dimension, while 2% will be less than 3mm and 13% will be greater than 3mm. Also, the distance between the CEJ and the crest of bone is 2mm on average. When this CEJ to crestal bone distance is less than 2mm, the gingiva ride up the clinical crown making the tooth appear submerged and short. If the CEJ to crestal bone distance is greater than 2mm, the CEJ may be exposed and the tooth will appear too long.
To summarize then, the biologic width is equal to 3mm: 1mm sulcular depth, 1mm attachment epithelium and 1mm connective tissue above the crestal bone. This is true on the broad facial surface. In the proximal papillae area, the correct biologic width increases to 4mm. This can be measured on any tooth using the "sounding" technique.
The "Hybrid Abutment": A New Design for Implant Cemented Restorations in the Esthetic Zones
Cemented implant restorations are widely used by many dentists. The traditional abutment design resembles a natural tooth prepared for a crown with a similar taper and a chamfer finish line. A frequent complication associated with implant restorations in the esthetic zones is the recession of buccal gingiva over time. Abutment morphology, among several other prosthetic factors, may play an important role in the stability of gingival margin in esthetically sensitive areas, but this has never been thoroughly analyzed. With many considerations in mind and recent techniques released, this article proposes the "hybrid abutment: design (HAD), a new design that includes a combination of the two types of features - a feather edge on the buccal side, and a chamfer finish line on the lingual side. This article also presents a rationale for the use of different abutment designs for different situations.
A Biometric Approach To Aesthetic Crown Lengthening: Part 1 - Midfacial Considerations
Although human dental anatomy is taught in university curricula, clinicians often witness restorations that are not proportional to one another. Dental restorations should also be proportional to periodontal supporting tissues as an essential aspect of dental anatomy. Measurements can be performed directly on a patient’s teeth with aesthetic gauges used to confirm the correct position of the supporting osseous topography. This article demonstrates a technique using these gauges to objectively determine the correct position of the underlying hard tissues and render predictable, aesthetic treatment.
Treatment of Excessive Gingival Display and Anterior Overeruption: Rehabilitation and Restoration
In order to develop a normal physiologic relationship
between the osseous crest and correct the incisal positioning of the gingival margin as related to the CEJ,
surgical correction of the patient’s excessive gingival display was required.
The Future of All-Ceramic Restorations
Dr. Blatz discusses the future of all-ceramic restorations.
Implant Supported Overdentures - Design Clinical Techniques and Tooth Selection
Dr. Aldo Leopardi's objective for this presentation is to focus on advanced clinical techniques and concepts for overdenture and fixed restoration of the completely edentulous patient.
Comprehensive Esthetic Therapy in a Patient with an Intra-capsular Disorder - Part 1 of 2
Dr. Rob Ritter discusses comprehensive esthetic work-up and treatment planning in the reconstruction of a patient with an existing intra-capsular disorder.
The Artist Within: How to Create Exceptional Looking Provisionals
In this webinar, Dr. Lerner will demonstrate how smile design, tooth anatomy and the shades of contour, surface texture and colour are all components of a beautiful smile.
Achieving Stable Esthetic Results with Implant Supported Restorations
We will discuss basic concept regarding immediate implant placement and guided bone regeneration procedure related to the esthetic zone before focusing on the soft tissue management. We will describe the prosthetic procedures which are performed before, during and after the surgical procedures. Provisional restorations, impression techniques, prosthetic profiles and restorative materials will be presented. The purpose of the presentation is to provide a check list that will guide the clinician developing a proper analysis and diagnosis for the successful esthetic result with implant supported restoration.
Multidisciplinary Crowns & Bridges
A 5 part course worth 1 CEU.
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