Evaluation of the Prevalence of Different Treatment Failure Modes after Crown Lengthening Surgical Procedures

Amirreza Babaloo, Mahdi Rahbar, Shima Ghasemi, Mohammad Taghi Chitsazi, Saman Abbasi


Introduction: Preservation of the health of periodontium is very important for the long-term success of restored teeth and a balance should always be created between the patients’ esthetic requirements and the periodontal health. Failures of crown lengthening procedures are classified into early and late failures. The aim of this study was to evaluate the prevalence of early failures of crown leathering surgical procedures. Materials and methods: In this descriptive/cross-sectional study, 96 patients were selected from those referring to the Department of Periodontitis, Tabriz Faculty of Dentistry, who required crown lengthening procedures. The particulars of these patients were recorded in special forms and the reasons for the failure of surgical procedures were separately determined at 2- and 6-week intervals. In addition, the frequencies of the reasons for failures were determined in percentages and absolute frequencies. Data were analyzed with descriptive statistics (frequencies and percentages) using SPSS 21. Statistical significance was set at P<0.05. Results: Evaluation of patients 6 weeks after surgery showed a failure rate of 14.5% for crown lengthening procedures in patients referring to the Department of Periodontics, Tabriz Faculty of Dentistry. The most common reasons for such early failures in the 6th week, in descending order, were a lack of sufficient keratinized gingiva around in tooth in question, fracture of the tooth structure after surgery, inadequate surgery (not creating a proper distance between the healthy margin and the crest) and the coronal returning of the gingival tissue on the tooth. A lack of sufficient keratinized gingiva around the tooth was the most frequent reason for the early failure of crown lengthening procedure at both study intervals. Conclusion: It can be concluded from the results of the present study that during the 6th postoperative week the crown lengthening procedures exhibited a 14.5% failure rate and a lack of sufficient keratinized gingiva around the tooth was the most frequent reason for early failures of such procedures.


Key words: Crown lengthening surgical procedures; treatment failure; keratinized gingiva;

Full Text:



Bader JD, Rozier RG, McFall WT, Ramsey DL. Effect of crown margins on periodontal conditions in regularly attending patients. The Journal of prosthetic dentistry. 1991;65(1):75-9.

Bader J, Rozier R, McFall W. The effect of crown receipt on measures of gingival status. Journal of dental research. 1991;70(10):1386-9.

Carranza FA, Newman MG, Takei H, Klekkevold PR. The periodontal pocket. Clinical Periodontology, 10th ed Philadelphia: Saunders/Elsevier. 2006:881-91,15-20.

Orkin D, Reddy J, Bradshaw D. The relationship of the position of crown margins to gingival health. The Journal of prosthetic dentistry. 1987;57(4):421-4.

Block P. Restorative margins and periodontal health: a new look at an old perspective. The Journal of prosthetic dentistry. 1987;57(6):683-9.

Lanning SK, Waldrop TC, Gunsolley JC, Maynard JG. Surgical crown lengthening: evaluation of the biological width. Journal of periodontology. 2003;74(4):468-74.

Nevins M, Skurow H. The intracrevicular restorative margin, the biologic width, and the maintenance of the gingival margin. The International journal of periodontics & restorative dentistry. 1984;4(3):30.

Minsk L. Esthetic crown lengthening. Compendium of continuing education in dentistry (Jamesburg, NJ: 1995). 2001;22(7):562.

Studer S, Zellweger U, Schärer P. The aesthetic guidelines of the mucogingival complex for fixed prosthodontics. Practical periodontics and aesthetic dentistry: PPAD. 1996;8(4):333-41; quiz 42.

Gargiulo AW, Wentz FM, Orban B. Dimensions and relations of the dentogingival junction in humans. Journal of Periodontology. 1961;32(3):261-7.

Kois J. " The gingiva is red around my crowns"--a differential diagnosis. Dental economics-oral hygiene. 1993;83(4):101-2.

Parma-Benfenali S, Fugazzoto P, Ruben M. The effect of restorative margins on the postsurgical development and nature of the periodontium. Part I. The International journal of periodontics & restorative dentistry. 1984;5(6):30-51.

Pontoriero R, Carnevale G. Surgical crown lengthening: a 12-month clinical wound healing study. Journal of Periodontology. 2001;72(7):841-8.

Smith DH, Ammons Jr WF, Van Belle G. A Longitudinal Study of Peridontal Status Comparing Osseous Recontouring With Flap Curettage: I. Results After 6 Months. Journal of periodontology. 1980;51(7):367-75.

Oakley E, Rhyu I-C, Karatzas S, Gandini-Santiago L, Nevins M, Caton J. Formation of the biologic width following crown lengthening in nonhuman primates. The International journal of periodontics & restorative dentistry. 1999;19(6):529-41.

Hempton TJ, Dominici JT. Contemporary crown-lengthening therapy: a review. The Journal of the American Dental Association. 2010;141(6):647-55.

Wilderman MN, Pennel BM, King K, Barron JM. Histogenesis of repair following osseous surgery. Journal of periodontology. 1970;41(10):551-65.

Brägger U, Lauchenauer D, Lang N. Surgical lengthening of the clinical crown. Journal of clinical periodontology. 1992;19(1):58-63.

Ayubian N. Evaluation of dimensional changes of supraosseous gingiva following crown lengthening. Journal of Periodontology & Implant Dentistry. 2011;2(2):61-5.

Pérez JR, Smukler H, Nunn ME. Clinical evaluation of the supraosseous gingivae before and after crown lengthening. Journal of periodontology. 2007;78(6):1023-30.

Deas DE, Moritz AJ, McDonnell HT, Powell CA, Mealey BL. Osseous surgery for crown lengthening: a 6-month clinical study. Journal of periodontology. 2004;75(9):1288-94.

Arora R, Narula SC, Sharma RK, Tewari S. Evaluation of supracrestal gingival tissue after surgical crown lengthening: a 6-month clinical study. Journal of periodontology. 2013;84(7):934-40.

Han W, Ouyang X, Wang X. [Prospective study on results of the surgical crown lengthening and its associated factors]. Zhonghua kou qiang yi xue za zhi= Zhonghua kouqiang yixue zazhi= Chinese journal of stomatology. 2004;39(4):280-3.

Diniz DE, Okuda KM, Fonseca CR, Gonzalez MKS, Greghi SLA, Valle ALd, et al. Surgical crown lengthening: a 12-month study-radiographic results. Journal of Applied Oral Science. 2007;15(4):280-4.

Müller H-P, Eger T. Masticatory mucosa and periodontal phenotype: a review. The International journal of periodontics & restorative dentistry. 2002;22(2):172-83.


  • There are currently no refbacks.

Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 International License.

2013-2023 (CC-BY) Australian International Academic Centre PTY.LTD.

Advances in Bioscience and Clinical Medicine