Treatment of Altered Passive Eruption: Periodontal Plastic Surgery of the Dentogingival Junction

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CASE REPORT Publication Treatment of Altered Passive Eruption: Periodontal Plastic Surgery of the Dentogingival Junction Roberto Rossi, DDS, MScD Private Practice Genoa, Italy Remo Benedetti, MD, DDS Private Practice Genoa, Italy Regina Isabel Santos-Morales, DMD Private Practice Makati City, Philippines Correspondence to: Dr Roberto Rossi Torre San Vincenzo 2, 16121 Genova, Italy; phone: 39 010 5958853; fax: 39 010 3460429; e-mail: drrossi@mac.com 212

ROSSI ET AL Publication Abstract Excessive gingival display, frequently seen in adults and resulting in short clinical crowns, has been described in the literature several authors as altered passive eruption. It is defined as a dentogingival relationship wherein the gingival margin is positioned coronally on the anatomic crown and does not approximate the cementoenamel junction due to the disruption in the development and eruptive patterns of the dentogingival unit. This article describes how periodontal plastic surgery can remodel the attachment apparatus, reestablish the correct biologic width, eliminate the excessive show of gingiva, and expose the correct dimensions of teeth. Apically repositioned flaps with osseous recontouring can restore gingival health and the esthetic parameters of the smile line. (Eur J Esthet Dent 2008;3:212 223.) 213

CASE REPORT Publication The periodontal literature has described delayed or altered passive eruption as the condition in which the patient presents with an excessive show of gingiva upon smiling and when the gingival margin overlaps the anatomical crown resulting in short clinical crowns. 1 4 This display of excessive pink soft tissue is also referred to as gummy smile. 5 Anatomical consideration In a normal situation, an adult dentate patient should display a dentogingival relationship where the gingival margin is located on the enamel approximately 0.5 to 2 mm coronally to the cementoenamel junction (CEJ). 2 The gingival margin is located on the enamel whereas the junctional epithelium is located between the base of the sulcus and the CEJ. The connective tissue attachment apparatus has its fibers embedded into the cementum and is located between the alveolar bone and the CEJ. The mucogingival junction is located apical to the crest of bone. The histologic relationships of the dentogingival junction were studied Sicher in 1959. 6 It is composed of, first, the connective tissue fiber attachment of the gingiva, and second, the epithelial attachment. 6 In 1961, Gargiulo et al studied these dimensions using human cadaver teeth. 7 They found the distance from the base of the epithelial attachment to the crest of alveolar bone (connective tissue attachment) to be constant. The mean average length in all stages of eruption was 1.07 mm. The epithelial attachment was variable and averaged 0.97 mm. 7 Biologic width was defined Cohen in 1962 as the space provided on the root surface the attachment of the connective tissue and the epithelial attachment. 8 Biologic width has also been defined Ingber et al as the actual measurement between the bottom of the gingival sulcus and the alveolar bone crest. 9 They found that in healthy normal gingiva, the distance from the CEJ to the crest of the alveolar bone is on average 1.55 mm. They claim that this space is necessary a healthy and stable attachment apparatus. This value should be understood as a theoretical mean as there have been no studies to show the variability of this value in humans. There have been several studies to determine the accuracy of dentogingival measurements. Using cadaver jaws, Vacek et al support the concept that the connective tissue attachment is less variable than the epithelial attachment. 10 Their mean measurements were 1.14 mm and 0.77 mm epithelial and connective tissue attachments, respectively, and these were different from the previous paper. Another paper, Boyle et al, investigated the interproximal bone crest levels in clinically healthy patients ranging in age from 11 to 70 years using bitewing radiographs. 11 Measurements taken from the CEJ to the alveolar bone crest ranged between 0.2 mm and 2.15 mm, with a mean distance of 1.24 mm. They found a graphic expression of regression of CEJ alveolar bone crest distance with age. One of the conclusions of this study was that the normal CEJ alveolar bone crest distance of 1.5 mm described Gargiulo et al 7 has large variations, and may often be as little as 0.2 mm. A more recent study, Alpiste-Illueca, using a reproducible radiographic technique, found values of 2.05 mm the CEJ alveolar bone crest distance and 2.0 mm biologic width. 12 These results corroborate the notion that 214

ROSSI ET AL Publication a b Fig 1 (a and b) Initial presentation. the dimensions of the dentogingival unit are highly variable. The biologic width becomes significant when maintaining gingival health of tissues restorative, orthodontic, periodontal, and esthetic concerns. Coslet et al have classified altered passive eruption in adult patients as follows. 1 Gingival/anatomic crown relationship: Type I gingival margin incisal to the CEJ, where there is a noticeably wider gingival dimension from the margin to the mucogingival junction. Type II dimension from the gingival margin to the mucogingival junction which appears to be within the normal mean width, as described Bowers 3 and Ainamo and Loe. 2 Alveolar crest CEJ relationship: Subtype A the alveolar crest CEJ distance is approximately 1.5 mm. This allows normal attachment of the gingival fibers into cementum. Subtype B the alveolar crest is at the level of the CEJ. Case reports Clinical case 1 (Figs 1 to 5) This is the case of a 30-year-old female complaining of excessive gingival display and short clinical crowns. The patient showed poor oral hygiene and spontaneous bleeding in several sites (Fig 1). After initial therapy consisting of oral hygiene instruction, scaling, and root planing, the gingival condition improved. However, the gingival margin remained on the enamel coronal to the CEJ (Fig 2). Debridement reduced inflammation, allowing accurate evaluation of the extent of altered passive eruption. This case was diagnosed as delayed passive eruption of type II, subtypes A and B, depending on the sites. Radiographic examination revealed no bone loss, and some areas showed bone closely approximating the CEJs of the teeth. Probing depth was 3 to 4 mm, revealing the presence of pseudopockets. Bone sounding was carried out to determine the level 215

CASE REPORT Publication Fig 2 Reevaluation stage after initial therapy. a b c Fig 3 (a, b and c) Intraoral views showing osseous contours upon flap reflection. Both central incisors (b) do not have room the connective tissue and the epithelial attachment (2.0 mm) as the osseous crest is <1mm from the CEJ. a b c Fig 4 (a, b and c) After osseous resective surgery, the interproximal bone has been shaped to accommodate the soft tissue contours and the alveolar crest has been scalloped to provide room the biologic width. 216

ROSSI ET AL Publication Fig 5 Five-year followup shows stability of the established dentogingival interface. of buccal bone and the position of the CEJ in relation to the gingival margin. After local anesthesia was administered, marginal incisions were permed. Fullthickness flaps were reflected buccally and palatally to expose the underlying bone. The height and thickness of the bone showed biologic width was minimal (0.5 mm) on the two maxillary central incisors and 1.5 mm on the lateral incisors (Fig 3). In some areas, such as the maxillary left bicuspids, the alveolar bone was at the CEJ, thus impinging the biologic width. An osseous resective procedure provided biologic width of 2 mm in all teeth, thus creating more space the soft tissue to be repositioned approximately at the CEJ (Fig 4). Scalloping of the gingiva was then permed using a no. 15c blade. The flaps were sutured back with vertical mattress sutures to reposition the papillae in the in- terproximal areas. During a recall visit of the patient 5 years after the procedure, the established dentogingival unit appeared stable (Fig 5). In summary, reducing soft tissue inflammation, apical repositioning of gingival flaps, and establishing a new biologic width (2.0 mm) through osseous resective surgery, the chief complaint of the patient was met with an esthetic outcome. Clinical case 2 (Figs 6 to 20) This is the case of a 27-year-old female complaining of gummy smile and short clinical crowns (Figs 6 to 9). The patient was tall and her short clinical crowns were disproportionate to her face and her smile. The patient exhibited adequate oral hygiene. Radiographs showed very limited biologic width on all the teeth of the upper arch 217

CASE REPORT Publication Fig 6 The smile at rest position during the consultation visit. Fig 7 The gummy smile at the consultation visit. a b c Fig 8 (a, b and c) Preoperative smile line. a b c Fig 9 (a, b and c) Preoperative clinical view. 218

ROSSI ET AL Publication (Fig 10). The diagnosis was altered passive eruption type I subtype B. The treatment plan was to remove the excessive soft tissue to expose the teeth fully to their natural length and to remove osseous structure to give room a biologic width of at least 2 mm. In some areas, one-third of the clinical crowns were covered with gingiva. The clinical crown of the central incisor was only 8 mm. However, the radiographic length measured 12 mm (Figs 11 and 12). The extent of soft tissue removal each Fig 10 Radiograph showing the limited biologic width; the osseous crest is close to cementoenamel junction level. Fig 11 Central incisor: the anatomical crown length was 12 mm. Fig 12 Central incisor: the clinical crown length was only 8 mm. Fig 13 Initial scalloping of the soft tissues, through submarginal incisions. Fig 14 Removal of excessive soft tissue showing the correct clinical crown exposure. 219

CASE REPORT Publication a b c Fig 15 level. Thick, bulbous osseous contours upon flap elevation, situated at almost the cementoenamel junction a Fig 16 (a and b) Frontal view following osseous plastic surgery to provide space the biologic width. b tooth was measured clinically and radiographically prior to the procedure. The surgical planning anticipated the removal of at least 1 mm of alveolar bone at all the sites to restore the correct minimum biologic width and to allow correct bone remodeling in order to provide adequate scalloping and architecture (Fig 13). Fig 17 Single interrupted sutures in place. After local anesthesia was administered, scalloped incisions were made using a no. 15c blade to mark the extent of soft tissue removal (Fig 13). Soft tissues were removed and the true lengths of the clinical crowns were exposed (Fig 14). Full mucoperiosteal flaps were elevated buccally and palatally to expose the thick, bulbous bony architecture (Fig 15). Osseous crests were found approximating the level of the CEJ, thus not allowing the proper biologic width. Osseous recontouring provided at least 2 mm space between the CEJ and the crest of the alveolar bone from teeth 15 to 25, eliminating the thick bony ledges (Fig 16). The flap was repositioned apically using single interrupted resorbable sutures (Fig 17). At the 6-month recall the patient showed a marked improvement in soft tissue quality (Figs 18 to 20). The smile line showed the full length of the teeth, with remarkable esthetic enhancement of the smile. 220

ROSSI ET AL Publication a b c Fig 18 (a, b and c) Healing at 6 months, showing healthy gingiva and proper exposure of enamel. a Fig 19 smile. b The new smile line displays the appropriate amount of teeth and soft tissue, eliminating the gummy Discussion Altered passive eruption is an uncommon occurrence that is only diagnosed upon clinical observation. It is defined as a dentogingival relationship wherein the margin of the gingiva is positioned incisally/occlusally on the anatomic crown in adulthood and does not approximate the cementoenamel junction. 13 This means that the crowns of the teeth appear very short and thus project a gummy smile. The incidence of this condition has not been fully studied in adults, although Volchansky and Cleaton- Jones, in a study in children aged between 6 and 16 years, found the incidence to be 12%. 14 In this study, they also observed that clinical crown height increases with increasing age. Thus, tooth eruption and mation of the dentogingival junction should be clearly understood prior to any treatment. Fig 20 The new smile shows overall enhanced facial esthetics. 221

CASE REPORT Publication In normal dentition, teeth and their alveoli actively erupt from their crypts. They continue to erupt through the gingiva until they make occlusal contact with the teeth in the opposing arch. 15 Orban and Kohler in 1924 described the various stages of eruption of teeth. 16 In stage 1, the epithelial attachment is situated along the enamel surface immediately above the CEJ. In stage 2, the epithelial attachment is situated along both the enamel above the CEJ and the cementum surface of the root of the tooth. In stage 3, the epithelial attachment is situated only on the cementum, immediately below the CEJ. Stages 1 to 3 are physiologic in nature. Finally, in stage 4 the epithelial attachment migrates apically due to periodontal disease or other pathologic conditions. Variations in the height of the gingival margin on the anatomic crown have been observed in adults at various ages. Volchansky and Cleaton-Jones found that in a study in children aged between 6 and 16 years, 12.1% of the 1,025 evaluated patients exhibited delayed passive eruption. 17 The same study found that eruption of teeth was completed the age of 12 years the maxillary central incisors and canines, and the maxillary lateral incisors continued to demonstrate minor changes in gingival margin position up to 16 years of age. However, Morrow et al suggest that passive eruption, resulting in increased clinical crown length, seems to continue throughout the teenage years, until the age of 19. 18 It is, theree, imperative that age is also considered bee treating altered passive eruption cases. Esthetic considerations The dental practitioner can influence the smile correcting tooth length problems, as in altered passive eruption cases. This should be considered in relation to the lip line of the patient. Tooth length has been studied in the literature; Townsend reported that canines and central incisors should be at the same length, and the lateral incisor should be 1 to 2 mm shorter. 19 There should be an interdental papilla of 4.5 to 5 mm from the tip of the papilla to the depth of the marginal scallop, and the most apical part of the gingival scallop should reflect the angle of the long axis of the tooth. The author also mentioned that the mean crown length a maxillary central incisor is 13.5 mm; a maxillary lateral incisor, 12 mm; and a maxillary canine, 13 mm. Wheeler s textbook 20 also reported on tooth sizes, giving average lengths maxillary anterior clinical crowns measured on extracted teeth. The values given were 10.5 mm maxillary incisors, 9 mm lateral incisors, and 10 mm canines. These values should serve as guides and should be regarded as one important aspect of esthetic treatment. Gingivectomy procedures can be permed using these values, while also keeping in mind Loe and Ainamo s description of the ideal clinical crown size a particular patient (Fig 13). 2 222

ROSSI ET AL Publication Resective procedure Once the level of the gingiva has been established, selective osseous recontouring can be achieved perming submarginal incisions to the desired height of the clinical crown. 20 A biologic width of at least 2 mm between the alveolar crest and the CEJ should be attained to ensure the health of the attachment apparatus (Fig 16). The thickness of the gingiva should also be taken into consideration when the flaps are replaced, and maintenance of a good zone of attached gingiva should also be addressed. References Conclusions This paper provides clinical and biologic presentations on the treatment of altered passive eruption, using periodontal plastic procedures such as esthetic crown lengthening. Altered passive eruption occurs on patients who exhibit unesthetic short clinical crowns with gummy smiles. The dentogingival dimensions are taken into consideration in careful diagnosis and treatment planning of the cases. Clinical and radiographic examinations dictate the necessary removal of soft and hard tissues to achieve the desired result. The reestablishment of a new and correct biologic width and the exposure of the correct length of the clinical crown leads to excellent clinical, biologic, and esthetic outcomes. 1. Coslet G, Vanarsdall R, Weisgold A. Diagnosis and classification of delayed passive eruption of the dentogingival junction in the adult. Alpha Omegan 1977;3:24 28. 2. Ainamo J, Loe H. Anatomical characteristics of gingiva. A clinical and microscopic study of the free and attached gingiva. J Periodontol 1966;37:5 13. 3. Bowers GM. A study of the width of attached gingival. J Periodontol 1963;34:201 209. 4. Gottlieb B, Orban B. Active and passive continuous eruption of teeth. J Dent Res 1933;13:213 214. 5. Levine RA, McGuire M. The diagnosis and treatment of the gummy smile. Compend Contin Educ Dent 1997;18:757 762. 6. Sicher H. Changing concepts of the supporting dental structures. Oral Surg Oral Med Oral Pathol 1959;12:31 35. 7. Gargiulo A, Wentz F, Orban B. Dimensions and relations of the dentogingival function in humans. J Periodontol 1961;32:261 267. 8. Cohen DW. Pathogenesis of Periodontal Disease and its Treatment. Washington, DC: Walter Reed Army Medical Center, 1962. 9. Ingber JS, Rose LF, Coslet JG. The biologic width : A concept in periodontics and restorative dentistry. Alpha Omegan 1977;70:62 65. 10. Vacek JS, Gher ME, Assad DA, Richardson AC, Giambarresi LI. The dimensions of the human dentogingival junction. Int J Periodontics Restorative Dent 1994;14:155 165. 11. Boyle W, Via F, McFall W. Radiographic analysis of alveolar crest height and age. J Periodontol 1973;44:236 243. 12. Alpiste-Illueca F. Dimensions of the dentogingival unit in the maxillary anterior teeth: A new exploration technique (parallel profile radiograph). Int J Periodontics Restorative Dent 2004;24:386 396. 13. Volchansky A, Cleaton-Jones P. Delayed passive eruption a predisposing factor to Vincent s infection. J Dent Assoc S Africa 1974;29:291 294. 14. Volchansky A, Cleaton-Jones P. The position of the gingival margin as expressed clinical crown height in children in ages 6 16 years. J Dent Assoc S Africa 1975;4:116 122. 15. Evian CI, Cutler SA, Rosenberg ES, Shah RK. Altered passive eruption: The undiagnosed entity. J Am Dent Assoc 1993;124:107 110. 16. Orban B, Kohler, J. The physiologic gingival sulcus. Z Stomatol 1924;22:353. 17. Volchansky A, Cleaton-Jones P. Clinical crown height (length) a review of published measurements. J Clin Periodontol 2001;28:1085 1090. 18. Morrow LA, Robbins JW, Jones DL, Wilson NHF. Clinical crown length changes from age 12 19: A longitudinal study. J Dent 2000;28:469 473. 19. Townsend CL. Resective surgery: An esthetic application. Int 1993;24:535 542. 20. Wheeler RC (ed). Wheeler s atlas of tooth m, ed 5. Philadelphia: WB Saunders, 1984:136 138. 223