Page 12 - GP Fall 2020

A Conservative Method of Subgingival Overhang Removal on a
Terminal Tooth: A Case Report

By Erini Farid, Shariss Ostrager, DDS, Mary Salama, DDS, Tejal Gohil, BDS,
Francis F Tung, DMD, MPH, and Analia Veitz-Keenan, DDS

Introduction loss of periodontal attachment than those Patient Description
The goal of restorative dentistry is to re- without. 4,7,10,13 A 26-year-old female with a non-contribu-
establish the function, esthetics, and form, tory medical history, presented to NYU Col-
of the teeth involved, with the intention of Correction of a restorative overhang has lege of Dentistry in 2016 for comprehensive
preventing any recurrent decay. A common been consistently shown to increase gingi- care with the chief complaint, “I am here
1
problem encountered in operative dentistry val and periodontal health parameters. This for a check up.” Clinical examination re-
is a restorative overhang, defined as “an ex- is because the provision of smooth margins vealed low caries risk and good periodontal
tension of restorative material beyond the enables plaque control and effective plaque health, however, an incidental finding was
confines of a cavity preparation.” Reports removal. 7,10,13 Studies have shown that when noted on radiographic exam. Her lower left
2,3
have indicated that the prevalence of over- overhangs are removed from restorations, a mandibular second molar (tooth #18) had
hangs may be as high as 76% of restored decrease in probing depths, gingival crevic- a subgingival restoration with a significant
surfaces, and is most frequently seen on ular fluid (GCF) volume, and disease-asso- overhang. The patient reported that she had
interproximal surfaces of posterior teeth. ciated microflora are all seen, along with an her impacted third molars extracted because
2-4
Overhanging restorations may be the result increase in alveolar bone support. 6,10 The re- they were causing decay. Post-extraction,
of numerous factors. Dental operators are duction in probing depths and GCF volume her previous dentist had gained access to the
more likely to produce restorations with an indicates a reduction of periodontal inflam- decay on tooth #18 and performed a subgin-
overhang when there is limited access to mation, as GCF is composed of inflammato- gival restoration. Her previous dentist had
margins causing difficulty polishing, when ry enzymes and cytokines as well as tissue informed her that there was overhang on the
using low viscosity materials or with an im- breakdown products. 11,13 restoration due to difficulty with access.
proper or inappropriately used matrix sys-
tem. 3,5,6 In addition to these iatrogenic fac- There are numerous methods of correcting
tors, the risk of producing a restoration with a restorative overhang, most commonly by
overhang is greater in cases with subgingi- recontouring or by removal and replace-
val margins. 3,7,8,9 Establishing proper mar- ment of the restoration. The majority of
6
ginal integrity is further complicated by the methods reported in the literature are spe-
challenge for dental operators to clinically cific to amalgam overhangs, and it is noted
detect subgingival overhangs when check- that composite overhang correction is more
ing the outcomes of restorative therapy pro- challenging and has fewer available repair
vided; as such, radiographic assessment is techniques. With the trend of restorative
3,8
the most reliable way to detect a restorative dentistry favoring composite restorations
overhang. 10 over amalgam restorations, the prevalence
of restorative overhangs may increase.
3
Cervical overhangs pose concerns for the Many instruments are described as effec-
restorative and periodontal prognosis of re- tive in the removal of amalgam overhangs,
stored teeth through several mechanisms. 10,11 including sickle scalers, curettes, chisels,
From the restorative perspective, secondary ultrasonic scalers, trimmers, rotary instru-
caries are more common with overhang- mentation with diamond finishing burs, and
ing margins due to their increased plaque surgical blades. 4,6,8,9 Finishing strips of vari-
retention and microleakage. Overhangs ous thickness and coarseness have also been
4,6
also reduce access of interproximal clean- applied as a supplemental technique in re-
ing devices, which creates an environment moving restorative overhangs. Specifically,
4
that is more ideal for the accumulation of one study found that sickle scalers produced
plaque. 3,6,8,10 Increased plaque retention fur- the least smooth margins, and that diamond
ther affects periodontal prognosis, as plaque flame burs caused the greatest amount of
promotion disrupts the ecological balance tooth damage. Furthermore, damage to Figure 1. Pre-operative bitewing and periapical
6
in the gingival sulcus, shifting the subgingi- adjacent tooth structure and soft tissue was radiographs showing overhang on the distal of
val microflora from predominantly aerobic reported as the most common complication tooth #18.
gram-positive strains to destructive anaero- when removing an overhang. The body
4,6
bic gram-negative strains. 2,3,7,10 Accordingly, of literature evaluating different methods During her next periodic exam at NYU Col-
restorative overhangs are also known to be of composite resin and amalgam overhang lege of Dentistry, the patient was informed
involved in the development of gingivitis, removal is limited despite the heavy prev- again about the risk factors associated with
which may develop into periodontitis. 4-8,10-12 alence of overhangs and their resulting the overhang and was motivated to find a
Interproximal restorations with overhangs impact on restorative and periodontal prog- solution. Upon further examination, tooth
may also violate supracrestal attached tis- nosis. This case report details the correc- #18 had good periodontal health and no car-
6,8
sue (formerly known as biologic width). tion of a subgingival overhang of unknown ies noted. The restoration and overhang in
13
Consequently, it is well documented that material on the distal of a mandibular sec- question were completely subgingival and
teeth with overhanging restorations expe- ond molar without proximal contact using a were not visible clinically. An endodon-
rience greater gingival inflammation and minimally invasive technique. tic evaluation was completed. Tooth #18
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