Graduate Periodontics Program - Department of Periodontology and Dental Hygiene, Univer- sity of Detroit Mercy School of Dentistry, Detroit, MI, USAUnited States
Department of Periodontology and Dental Hygiene, University of Detroit Mercy School of Den- tistry, Detroit, MI, USAUnited States
Department of Biomedical and Diagnostic Sciences, University of Detroit Mercy School of Dentistry, Detroit, MI, USAUnited States
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The current case report presents a rare oral pathology of Oral Focal Mucinosis (OFM). The patient developed marginal gingival inflammation subsequent to esthetic crown lengthening surgery. The differential diagnosis included candidal infection, foreign body gingivitis, and Desquamative Gingivitis (DG). An incisional biopsy was performed, indicating a definitive histopathological diagnosis of OFM. OFM is a lesion developing due to over production of hyaluronic acid by fibroblasts, compromising the normal collagen production. Treatment of OFM is excisional biopsy, however; its location near the gingival margin in the aesthetic zone required a minimally invasive surgical approach. Therefore, a less invasive treatment using corticosteroids was administered, leading to resolution of the inflammation.
Keywords: Histology Pathology; Aesthetic Crown lengthening; Osseous Surgery; Mucinoses Rare diseases Complications; Histology; Pathology; Aesthetic; Crown lengthening; Osseous; Surgery; Mucino- ses; Rare diseases; Complications
Oral Focal Mucinosis (OFM) is an asymptomatic, benign soft tissue lesion of unknown 1-3 etiology.1-3 It presents as a pedunculated or sessile growth with most cases occurring in women.
OFM involves the keratinized oral mucosa, with 80% of the lesions developing on the gingiva
and the remainder on the palate. Although Tomich3 first reported 8 cases of the lesions as the oral
counterpart of cutaneous focal mucinosis, it is now recognized that OFM is a separate clinical
entity. Bharti and Singh4 stated that 57 cases of OFM have been reported in the English literature
and 3 in the Indian literature. To date a total of approximately 70 cases of oral focal mucinosis 3-17 have been reported in the literature.3-17
OFM lesions are difficult to diagnose because they have no distinct clinical features.
Therefore, they are often diagnosed as gingival hyperplasia, fibroma, pyogenic granuloma or 1-18 fibrous epulis.1-18 Histopathology of OFM shows a focal myxoid degeneration of the connective
tissue, possibly due to the over production of hyaluronic acid by fibroblasts during collagen
production, and is the definitive diagnosis for OFM.2 In the current case report, OFM occurred
after a routine crown lengthening procedure with clinical presentation resembling that of Des-
quamative Gingivitis (DG).
tient presented with provisional crowns on teeth #7, 8, 9, and
10 (Figure 1). The dental history revealed root canal treatment
and Porcelain Fused to Metal crowns (PFM). The clinical and
radiographic evaluations revealed altered passive eruption19
with impingement on biologic width (Figure 2).20 The treatment
plan included esthetic crown lengthening to increase the clinical
crown length to achieve an esthetically pleasing smile.
Teeth wax up was performed to determine the new
clinical crowns dimensions and a surgical guide was made. Es-
thetic crown lengthening was performed for teeth #4 through
#12 following the new clinical crowns dimensions. The surgical
area was closed using single interrupted vicryl sutures (Ethicon
Inc., Somerville, NJ, USA) and the flap stabilized with a poly-
ether urethane dimethacrylate resin-based dressing (Barricade,
Dentsply International Inc., Milford, DE, USA). The patient was
discharged in good condition and given post-operative instruc-
tions and Ibuprofen 800 mg and Chlorhexidine 0.12% mouth
wash prescriptions. The dressing was removed 2 weeks post-
surgery.
At five weeks post-surgery, the patient presented with
a severe well-demarcated gingival erythematous lesion close to
the free gingival margin of the surgical area (Figure 3). Although
the patient had no known allergies, it was thought that an allergic
reaction to methacrylate had occurred. Differential diagnoses
included candidal infection, foreign body gingivitis and DG. The
patient was advised to have a biopsy performed but declined.
The patient was prescribed Magic Mouthwash consisting of
five ingredients in a 1:1:1:1:1 ratio: Kaopectate (anti-acid
coating agent), Nystatin (anti-fungal), Diphenhydramine (anti-
histamine), Lidocaine (anesthetic) and Prednisolone (anti-
inflammatory), with instructions to use the mouth rinse 4 to 5
times per day.
At eight weeks post-surgery (after two weeks of using
the mouthwash), adequate healing of the soft tissues occurred but
the lesion was still present at the gingival margin extending from
tooth #5 to #9. The patient was referred to an allergist to rule out
reaction to the periodontal dressing. The test was negative to the
dressing but the patient tested positive to nickel allergy. Since
periosteal elevators have trace elements of nickel, it is possible
that some shavings were embedded in the soft tissues during the
crown lengthening surgery. The patient was prescribed systemic
Prednisolone 5 mg for 15 days. Dosage instructions were 5mg
every 6 hours for 5 days tapered down to every 12 hours for
another 5 days and finally once a day for the last 5 days.
At 12 weeks post-surgery marked improvement was
observed but the lesion had not completely resolved (Figure 4).
Adult dental prophylaxis was performed followed by gingivo-
plasty under local anesthesia from #5 to #9. After two weeks,
Triamcinolone acetonide 0.1% corticosteroid (Kenalog® in ® Orabase® Bristol-Myers Squibb Company Princeton, NJ, USA)
via tray was prescribed and significant reduction in erythema
occurred. Five months post-aesthetic crown lengthening proce-
dure and medications, the patient received permanent porcelain
crowns for teeth #7, 8, 9, and 10. At 1 year post-surgery, the
erythematous lesion was reduced but slightly evident on teeth
#8 and #9 (Figure 5). Biopsy was re-advised to the patient to
determine the etiology of the lesion, and the patient consented to
treatment. An incisional biopsy was performed obtaining speci-
mens from the facial gingival margins of teeth #8 and #9 (Figure
6). At 18 days post-biopsy the erythema was still present.
Three biopsy specimens were submitted for analysis
(Immco Diagnostics, Buffalo, NY, USA). The first specimen in
formalin fixation with hematoxylin and eosin staining was not ® consistent with immunologically recognizable autoimmune-me-
diated blistering diseases and therefore the suspected diagnosis
was DG (Figure 7). The second and third specimens were sub-
mitted for immunofluorescence analysis. The specimens were
taken from the gingiva of #9 and processed for immunofluores-
cence microscopy to analyze in vivo deposits of IgG, IgG4, IgA,
IgM, fibrin and complement C3. The specimens were denuded
of surface epithelium while the surrounding normal mucosa
showed an intact epithelium. Immunofluorescence analysis re-
vealed no significant deposits of immunoglobulin, complement
C3 or fibrin. The histopathological diagnosis was oral focal mu-
cinosis.
Although excisional biopsy has been proposed as the
correct treatment for oral focal mucinosis, this was not performed
in this case. Rather, incisional biopsy was performed due to the
aesthetic location and size of the lesion.
Oral focal mucinosis has been reported intraorally at
various locations, with the gingiva and hard palate being the
most common sites. Most of the reported cases have occurred
in females. Tomich3 described it as an oral counterpart of
cutaneous focal mucinosis, but in later reports it has emerged
as a distinct entity. Although its definitive diagnosis is based on
histopathology,a common finding is that its clinical presentation is
mostly on keratinized tissue overlying bone. Clinical differential
diagnosis of OFM cases reported has varied in the literature
and includes fibrous hyperplasia, giant cell fibroma, peripheral
giant cell granuloma, peripheral ossifying fibroma, peripheral
odontogenic fibroma, squamous papilloma, mucoceole and 1-18 pyogenic granuloma.1-18 To the authors knowledge, this is the
first case reported where OFM has resembled the appearance of
DG.
Periodontal esthetic crown lengthening surgery is com-
prised of osteotomy and osteoplasty. Osseous re-contouring in-
flicts trauma to the periodontal tissues and may have contributed
to the development of the lesion in this case. There is contro-
versy as to whether local trauma plays a role in the etiology of
OFM. While Tomich hypothesized that trauma may not be re- 3 18 lated to OFM,3 while Gnepp et al18 claimed that trauma may be
a contributing factor for the development of OFM soft tissue
lesions. In support of the latter, Neto et al8 suggested that fibro-
blasts stimulated by trauma from surgically assisted rapid maxil-
lary expansion produced hyaluronic acid, not osteoid tissues and
caused oral focal mucinosis in a young female patient. Lesions
on the marginal gingiva occurring on the maxillary facial aspect
can be challenging to treat, with esthetics being a major con-
cern. Even though excisional biopsy is the treatment of choice
for OFM, in the present case gingivoplasty was performed. Gin-
givectomy was not the appropriate treatment of choice because
of aesthetics. The marginal erythema significantly subsided at
OFM may be considered in the differential of yet an-
other clinical lesion, namely desquamative gingivitis (DG). The
literature has reported many different forms of OFM but the di-
agnosis can only be confirmed with histopathology. The current
case report highlights oral focal mucinosis as a viable differen-
tial diagnosis when evaluating a clinical appearance consistent
with desquamative gingivitis (DG).
The authors thank Dr. Lakshmanan Suresh for histopathological
consultation.
SOURCES OF SUPPORT: None.
The authors declare that they have no conflicts of interest.
The patient has provided written permission for publication of
the case details and images.