The restoration of teeth with clinically short crowns poses a multifactorial challenge in modern restorative and prosthetic dentistry.
Inadequate coronal tooth structure compromises the retention, resistance, and marginal integrity of restorations, often leading to restorative failure, periodontal inflammation, or esthetic dissatisfaction.
This clinical scenario is frequently encountered in cases of altered passive eruption, subgingival caries, extensive tooth wear, and fractures close to or below the gingival margin.
To overcome these limitations, periodontal plastic surgery—particularly crown lengthening procedures—has emerged as a critical component of interdisciplinary dental treatment planning.
These procedures aim to harmonize the interface between hard and soft tissues, create sufficient supragingival tooth structure for optimal prosthetic outcomes, and ensure the preservation of periodontal health by respecting the biologic width.
Importantly, the demand for esthetic outcomes in both anterior and posterior zones has elevated the role of periodontal plastic surgery beyond simple functional correction.
Today, it is an integral part of comprehensive esthetic rehabilitation, requiring collaboration between periodontists, prosthodontists, and restorative dentists.
Understanding the Problem: What Are Clinically Short Crowns?
A "clinically short crown" refers to a situation where insufficient coronal structure is exposed above the gingival margin, impairing the preparation, retention, and longevity of prosthetic restorations such as crowns or bridges.
This can be caused by:
✔ Altered passive eruption (APE)
✔ Subgingival caries or restorations
✔ Tooth wear (abrasion, attrition, erosion)
✔ Cervical fractures
✔ Gingival overgrowth due to medications or inflammation
If prosthetic margins are placed too deep to compensate, biologic width violation may occur, leading to chronic gingival inflammation, attachment loss, and bone resorption.
Periodontal Plastic Surgery and Crown Lengthening Techniques
Crown lengthening surgery is designed to apically reposition the gingival and, if necessary, the alveolar bone to expose additional tooth structure.
There are several surgical modalities depending on the clinical case:
✔ Gingivectomy (for thick biotypes with sufficient keratinized tissue)
✔ Apically positioned flap (APF) with or without osseous resection
✔ Laser-assisted gingival contouring
✔ Guided crown lengthening using digital planning and surgical guides
These approaches are particularly effective when integrated with digital smile design (DSD) and CAD/CAM prosthetic workflows.
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Respecting the Biologic Width
The biologic width (approximately 2.04 mm on average) comprises the junctional epithelium and connective tissue attachment to the tooth.
Restoration margins must be placed at least 3 mm coronal to the alveolar crest to avoid biologic width infringement.
Failure to respect this dimension can result in:
✔ Persistent inflammation
✔ Pocket formation
✔ Bone loss
✔ Patient discomfort
Therefore, surgical crown lengthening should always be guided by a biologic and prosthetic assessment, including radiographs, periodontal sounding, and esthetic analysis.
Clinical Integration and Prosthetic Planning
Successful prosthetic rehabilitation of short crowns involves:
✔ Establishing a ferrule effect of at least 1.5–2 mm
✔ Creating a stable, symmetric gingival architecture
✔ Facilitating ideal emergence profile for crowns
✔ Avoiding subgingival margin placement where possible
In high-esthetic-demand areas, soft tissue management must be approached conservatively and often combined with connective tissue grafting or papilla preservation techniques to maintain gingival harmony.
Long-Term Outcomes
Recent clinical studies report stable periodontal health, predictable tissue remodeling, and high patient satisfaction following well-planned crown lengthening procedures.
Healing generally occurs within 6–12 weeks, with tissue stability suitable for final prosthesis fabrication by 3–6 months postoperatively.
Conclusion
Periodontal plastic surgery, especially crown lengthening, is essential for predictable prosthetic rehabilitation in cases of clinically short crowns.
When executed with precise surgical technique and interdisciplinary coordination, it not only restores function but enhances esthetics and long-term periodontal stability.
In the era of digital dentistry and esthetic-driven treatments, the role of periodontally guided prosthetics has never been more relevant.
Scientific References
- Qali, A. et al. (2024). Clinical Considerations for Crown Lengthening.
- Martínez Hernández, R. & Marín González, M. G. (2019). Periodontal plastic surgery performed in clinically short crowns for prosthetic rehabilitation.
- International Dental Journal. Volume 74, Supplement 1, October 2024. Prosthodontic rehabilitation with crown lengthening by guided periodontal surgery.
- Ola Khairallah, Aseel Al-Mashout, Aous Dannan (2024). Oral Rehabilitation Case enhanced by Plastic Periodontal Surgery using Sub-epithelial Connective Tissue Grafting.
