medicina

Case Report
Full-Mouth Rehabilitation of a Patient with Gummy
Smile—Multidisciplinary Approach: Case Report
Kinga Mária Jánosi 1 , Diana Cerghizan 1, * , Florentin Daniel Berneanu 1,† , Alpár Kovács 2 , Andrea Szász 2 ,
Izabella Mures, an 1 , Liana Georgiana Hănt, oiu 1 and Aurit, a Ioana Albu 1

1 Faculty of Dental Medicine, George Emil Palade University of Medicine, Pharmacy, Science,
and Technology of Targu Mures, 38 Gh. Marinescu Str., 540142 Targu Mures, Romania
2 Private Practice, SC Maxdent Office SRL, 540501 Targu Mures, Romania
* Correspondence: diana.cerghizan@umfst.ro; Tel.: +40-740-076-876
† Authors with equal contribution as the first author.

Abstract: The impairment of aesthetic function leads to a decreased quality of life. An unaesthetic
smile due to excessive gingival exposure demands, most of the time, a complex treatment in which
the objective is the vertical reduction of the amount of exposed fixed gingiva by obtaining a complete
exposure of the anatomical crown of the teeth and restoring the ideal dimensions of the biological
width. This paper presents a case of a 48-year-old female patient who was unsatisfied with her
aesthetics and had disturbed masticatory function due to the absence of some posterior teeth. The
cone beam computed tomography was performed to evaluate the facial and dental morphology. The
treatment plan included diode laser and piezo-surgery utilization for the frontal area of the upper
arch and implants to restore the distal area of the lower and upper arch. Zirconia ceramic was used
for the final restorations. This complex and multidisciplinary full-mouth rehabilitation lasted for two
years, and the patient was pleased with the result. This case showed that a well-established treatment
plan is necessary to obtain long-lasting results. The use of adequate procedures and equipment
ensures a predictable result.

Keywords: oral rehabilitation; laser-assisted crown-lengthening; piezo-surgery; implants; zirconia ceramics

Citation: Jánosi, K.M.; Cerghizan, D.;
Berneanu, F.D.; Kovács, A.; Szász, A.;
Mures, an, I.; Hănt, oiu, L.G.; Albu, A.I.
Full-Mouth Rehabilitation of a
Patient with Gummy Smile— 1. Introduction
Multidisciplinary Approach: Case Inadequate facial aesthetics due to an unaesthetic smile, especially in the case of a
Report. Medicina 2023, 59, 197. gummy smile, with a high smile line, can harm patients’ quality of life, even leading to
https://doi.org/10.3390/ psychical problems in some cases [1]. The American Academy of Periodontology (AAP)
medicina59020197 defines the gummy smile as a deformity and mucogingival condition that affects the area
Academic Editor: Gaetano Isola around the teeth [2]. The excessive gingival display is characterized by overexposure of
the maxillary gingiva during smiling or speaking [3]. According to Allen, gum exposure
Received: 9 December 2022 of less than 2–3 mm can be considered attractive. An overexposure of more than three
Revised: 5 January 2023
mm is known as the gummy smile [4] and is generally considered an aesthetic problem [5].
Accepted: 16 January 2023
In some European countries, a gingival display up to 4 mm or more is acceptable [4].
Published: 19 January 2023
Etiological factors related to a gummy smile can be gingival (passive eruption), skeletal
(vertical maxillary excess), and muscular (upper lip hyperfunction) [6]. The high smile line
and excessive gingival exposure must be considered during the treatment plan [6] because
Copyright: © 2023 by the authors.
sometimes corrections are needed during full-mouth rehabilitation.
Licensee MDPI, Basel, Switzerland. The treatment procedure depends on the diagnosis and the etiological factors.
This article is an open access article Aesthetic crown lengthening is one of the most common surgical treatments for a
distributed under the terms and gummy smile. The objective of this procedure is the vertical reduction of the amount of
conditions of the Creative Commons exposed fixed gingiva by obtaining a complete exposure of the anatomical crown of the
Attribution (CC BY) license (https:// teeth and restoring the ideal dimensions of the biological width [7]. Following crown-
creativecommons.org/licenses/by/ lengthening surgery, the biological width is restored to a minimum of 2 mm, with the
4.0/). epithelial attachment of 0.97 mm and connective tissue of 1.07 mm width [8].

Medicina 2023, 59, 197. https://doi.org/10.3390/medicina59020197 https://www.mdpi.com/journal/medicina

 Aesthetic crown lengthening is one of the most common surgical treatments for a
gummy smile. The objective of this procedure is the vertical reduction of the amount of
exposed fixed gingiva by obtaining a complete exposure of the anatomical crown of the
teeth and restoring the ideal dimensions of the biological width [7]. Following crown-
Medicina 2023, 59, 197 2 of 11
lengthening surgery, the biological width is restored to a minimum of 2 mm, with the
epithelial attachment of 0.97 mm and connective tissue of 1.07 mm width [8].
During the development of the treatment plan, tridimensional imagistic investiga-
tionsDuring the development
are necessary. Cone beam of the treatment
computed plan, tridimensional
tomography (CBCT) can imagistic
provide investigations
accurate in-
are necessary. Cone beam computed tomography (CBCT) can provide accurate
formation about the alveolar bone and the periodontal status of the teeth. Measurements information
about
can bethe alveolarto
performed bone andthe
define thelength
periodontal status of the
of the anatomical teeth.
crown and Measurements
root, which iscan be
neces-
performed to define the length of
sary to realize the surgery correctly [9]. the anatomical crown and root, which is necessary to
realize the surgery correctly [9].
The greatest desire during the surgery is good visibility, without bleeding in the
The greatest
working area. The desire
diode during
laser’sthe surgery
most is goodadvantages
significant visibility, without
are the bleeding in theopera-
non-bleeding work-
ing
tivearea.
field,The diode
tissue laser’s most
evaporation significant
ability, advantages
adequate are the
sterilization ofnon-bleeding operative
the interventional areafield,
and
tissue evaporation ability, adequate
minimal postoperative pain and edema [10]. sterilization of the interventional area and minimal
postoperative pain and edema [10].
Piezo-surgery offers a promising alternative to bone resection with significant bene-
Piezo-surgery offers a promising alternative to bone resection with significant benefits
fits compared to traditional methods. It reduces the bleeding rate by 25–30% because it
compared to traditional methods. It reduces the bleeding rate by 25–30% because it does
does not damage the soft tissues or blood vessels, ensuring a clean operating field during
not damage the soft tissues or blood vessels, ensuring a clean operating field during the
the intervention [11]. Its combination with the minimal flap technique significantly re-
intervention [11]. Its combination with the minimal flap technique significantly reduces
duces postoperative pain and edema [12].
postoperative pain and edema [12].
The gingival phenotype and the suture technique influence the evolution of the heal-
The gingival phenotype and the suture technique influence the evolution of the healing
ing process after the surgery [13].
process after the surgery [13].
Dental implants have been considered one of the most important discoveries in den-
Dental implants have been considered one of the most important discoveries in den-
tistry in the past decades. In modern dentistry, the implant-prosthetic approach allows
tistry in the past decades. In modern dentistry, the implant-prosthetic approach allows the
the treatment of partially edentulous spaces with fixed restorations, considerably improv-
treatment of partially edentulous spaces with fixed restorations, considerably improving
ing patient’s
the the patient’s quality
quality of life
of life [14].
[14]. The
The implanttherapy,
implant therapy,combined
combinedwithwithzirconia
zirconia ceramic
ceramic
restorations, allows the rehabilitation of function and aesthetics
restorations, allows the rehabilitation of function and aesthetics [15]. [15].

2. Case
2. Case Report
Report
This case report
This case report isis aa full-mouth
full-mouth rehabilitation
rehabilitation of
of aa 48-year-old
48-year-old female
female patient.
patient. She
She
wanted to
wanted to improve
improve herher aesthetics,
aesthetics, disturbed
disturbed by thethe shape
shape andand orientation
orientation of the
the upper
upper
frontal teeth
frontal teeth and
and the
the excessive
excessive visibility
visibility of
of the
the gingiva.
gingiva. The patient also reports difficulties
difficulties
in mastication
mastication dueduetotothe
theabsence
absence of of
numerous
numerous posterior teeth
posterior in the
teeth in lower arch. arch.
the lower To estab-
To
lish the preliminary diagnosis, intraoral examinations (Figure 1a) and a
establish the preliminary diagnosis, intraoral examinations (Figure 1a) and a panoramic panoramic X-ray
(Figure
X-ray 1b) were
(Figure 1b) performed.
were performed.

(a) (b)
Figure 1. Initial situation of the patient: (a) Unaesthetic metal-ceramic crowns with chronic inflam-
Figure 1. Initial situation of the patient: (a) Unaesthetic metal-ceramic crowns with chronic inflam-
mation of the gingival margins and oblique interincisal line; (b) Initial panoramic X-ray.
mation of the gingival margins and oblique interincisal line; (b) Initial panoramic X-ray.
The clinical
The clinical examination
examination revealed
revealed the
the presence
presence of
of inadequate
inadequate metal-ceramic
metal-ceramic restora-
restora-
tions, teeth with unsatisfactory periodontal status (grade I mobility), aesthetical
tions, teeth with unsatisfactory periodontal status (grade I mobility), aesthetical and
and func-
func-
tional problems.
tional problems. A full-mouth CBCT
A full-mouth CBCT scan
scan was
was performed
performed for
for the
the final
final diagnosis
diagnosis and
and to
to
establish the treatment plan. The treatment objective was to perform full-mouth rehabilita-
tion and improve the smile’s aesthetics by reducing the excessive gingival displacement.
A crown-lengthening surgery was planned before the prosthodontic rehabilitation.
The long-term success of future restorations is conditioned by accurately reestablishing
the vertical dimension and the occlusal plane. The functional rehabilitation of the jaws
needed an implant-prosthodontic approach. The treatment plan was established following
the patient’s agreement, considering the principles of the Declaration of Helsinki involving
 establish the treatment plan. The treatment objective was to perform full-mouth rehabili-
tation and improve the smile’s aesthetics by reducing the excessive gingival displacement.
A crown-lengthening surgery was planned before the prosthodontic rehabilitation.
The long-term success of future restorations is conditioned by accurately reestablishing
Medicina 2023, 59, 197 the vertical dimension and the occlusal plane. The functional rehabilitation of the3 of jaws
11
needed an implant-prosthodontic approach. The treatment plan was established following
the patient’s agreement, considering the principles of the Declaration of Helsinki involv-
ing humans
humans as revised
as revised in 2013.
in 2013. Informed
Informed consent
consent was was obtained
obtained fromfrom the patient
the patient regarding
regarding the
the treatment, and written informed consent has been obtained to
treatment, and written informed consent has been obtained to publish this paper. publish this paper.
Thefull-mouth
The full-mouthrehabilitation
rehabilitationofofthis
thiscase
casewas
wasperformed
performedfor fortwo
twoyears.
years.
Basedon
Based onthe
theCBCT
CBCTmeasurements,
measurements,the thepostoperative
postoperativemaxillary
maxillarycrown/root
crown/rootratio
ratiowas
was
defined(Figure
defined (Figure2).
2).The
Theright
rightcentral
centralincisor
incisorpresented
presentedaashortshortroot
rootlength
lengthto
tosupport
supportfuture
future
exposureduring
exposure duringthethecrown-lengthening
crown-lengtheningprocedure.
procedure. Therefore,
Therefore, ititwas
wasdecided
decidedto toextract
extract
this tooth. The extraction of periodontally compromised 17 and 15 teeth
this tooth. The extraction of periodontally compromised 17 and 15 teeth was recommended was recom-
mended
with with implant-prosthodontic
implant-prosthodontic rehabilitation
rehabilitation of the rightofposterior
the right area.
posterior area.

Figure2.2.Evaluation
Figure Evaluationofofthe
theperiodontal
periodontalstatus
statusand
androot
rootlength
lengthofofthe
themaxillary
maxillaryteeth
teethon
onCBCT.
CBCT.

Thesurgical
The surgicalpre-prosthetic
pre-prosthetictreatment
treatment protocol
protocol combines
combines laser
laser therapy
therapy with
with the the pi-
piezo-
ezo-surgery
surgery to achieve
to achieve a minimally
a minimally invasiveinvasive intervention
intervention with reduced
with reduced postoperative
postoperative symp-
symptomatology.
tomatology. Intraoral
Intraoral mock-ups
mock-ups were created
were created to simulate
to simulate and individualize
and individualize future
future results
results
and and to
to guide guide
the the surgery
surgery (Figure 3).
(Figure 3).

(a) (b)
Figure3.3.Planning
Figure Planningthe
thesurgical
surgicaltreatment
treatmentoutcomes:
outcomes:(a)
(a)Initial
Initialmock-up;
mock-up;(b)
(b)Surgical
Surgicalguide.
guide.

Theold
The old restorations
restorations were removed.
removed. The Thesurgical
surgicalguide
guidewaswasrealized after
realized thethe
after prelim-
pre-
inary preparation
liminary preparation of of
thethe
abutments
abutmentswith
withthethe
vertical preparation
vertical technique.
preparation technique.During
Duringthe
the surgical
surgical interventions,
interventions, the Optragate
the Optragate (Ivoclar
(Ivoclar Vivadent
Vivadent AG, Schaan,
AG, Schaan, Principality
Principality of
of Liech-
Liechtenstein) retractor
tenstein) retractor waswas used,
used, which
which ensured
ensured goodvisibility
good visibilityand
andadequate
adequate access
access totothe
the
working
workingarea.
area.The
TheLasotronix
LasotronixSmart
SmartM MProProdiode
diodelaser
laser(Lasotronix
(LasotronixSp.
Sp.zzo.o.,
o.o.,Piaseczno,
Piaseczno,
Poland)
Poland)waswasused
usedfor
forthe
theguiding
guidingincisions
incisionsatatthe
thegingival
gingivalmargin,
margin,following
followingthethecervical
cervical
line
line of the mock-up. No elongation was performed at the right central incisor becausethis
of the mock-up. No elongation was performed at the right central incisor because this
tooth
toothneeded
neededto tobe
beextracted
extractedatatthe
theend
endof ofthe
thesurgery.
surgery.TheThealveolar
alveolarbone
bonemargins
marginswerewere
removed using the Ultrasurgery US-III LED piezo-surgery device (Guilin Woodpecker
Medical Instrument Co., Ltd, Guangxi, P. R. China) (Figure 4).
To obtain long-lasting results, the placement of the margins of the future restorations
must be at a minimum distance of 5 mm from the alveolar bone. Therefore, this desirability
was considered during the surgery (Figure 5).
 Medicina 2023, 59, x FOR PEER REVIEW
removed 4 of 11
using the Ultrasurgery US-III LED piezo-surgery device (Guilin Woodpecker
Medical Instrument Co., Ltd, Guangxi, P. R. China) (Figure 4).
Medicina 2023, 59, 197 4 of 11
removed using the Ultrasurgery US-III LED piezo-surgery device (Guilin Woodpecker
Medical Instrument Co., Ltd, Guangxi, P. R. China) (Figure 4).

(a) (b) (c) (d)

Figure 4. The used devices and the settings: (a) Lasotronix Smart M Pro laser; (b) The setting of the
laser device for the gingivectomy; (c) Ultrasurgery III LED piezo-surgery device; (d) The setting of
(a) (b)
the piezo-surgery device. (c) (d)
Figure 4. The used devices and the settings: (a) Lasotronix Smart M Pro laser; (b) The setting of the
Figure The used
To4.obtain devices andresults,
long-lasting the settings: (a) Lasotronix
the placement Smart
of the M Proof
margins laser;
the (b) The restorations
future setting of the
laser device for the gingivectomy; (c) Ultrasurgery III LED piezo-surgery device; (d) The setting of
laser device
must be at afor the gingivectomy;
minimum (c) Ultrasurgery III LED piezo-surgery device; (d) The setting of
the piezo-surgery device.distance of 5 mm from the alveolar bone. Therefore, this desirabil-
the was
ity piezo-surgery
considered device.
during the surgery (Figure 5).
To obtain long-lasting results, the placement of the margins of the future restorations
must be at a minimum distance of 5 mm from the alveolar bone. Therefore, this desirabil-
ity was considered during the surgery (Figure 5).

(a) (b) (c) (d)

Figure
Figure 5.
5. The
The steps
steps of
of the crown-lengthening surgery:
the crown-lengthening surgery: (a)
(a) The
The abutments
abutments after
after the
the removal
removal of
of the
the
old restorations and a preliminary preparation before the surgery; (b) Predefinition of the gingival
old restorations and a preliminary preparation before the surgery; (b) Predefinition of the gingival
(a) margins using the(b)surgical guide and the Lasotronix(c) Smart M Pro laser; (c) The(d) limits of the new
margins using the surgical guide and the Lasotronix Smart M Pro laser; (c) The limits of the new
gingival margins after the removal of the surgical guide; (d) The aspect of the prosthodontic field
Figure 5.margins
gingival The steps of the
theremoval
crown-lengthening surgery:
guide;(a)(d)The
Theabutments afterprosthodontic
the removal of the
after the piezo andafter
laser surgery. of the surgical aspect of the field
old restorations
after and
the piezo and a preliminary
laser surgery. preparation before the surgery; (b) Predefinition of the gingival
margins using the surgical guide and the Lasotronix Smart M Pro laser; (c) The limits of the new
Aftermargins
gingival
performing the surgeryofand
after the
extracting the(d) right central incisor, socket preser-
After performing theremoval
surgery andthe extracting
surgical guide;
the right The aspectincisor,
central of the prosthodontic
socket preserva-field
vation
after and
the bone
piezo augmentation
and laser surgery. were done to maintain the alveolar bone dimensions. Pro-
tion and bone augmentation were done to maintain the alveolar bone dimensions. Provi-
visional restoration was made to restore the aesthetics and function temporarily. Com-
sional restoration was made to restore the aesthetics and function temporarily. Complete
plete healing
After was achieved
the after six months. As expected, the central
results obtained were stable.
healing wasperforming
achieved after surgery
six andAs
months. extracting
expected,thetheright
results incisor,
obtained weresocket
stable.preser-
The
The gingival
vation and contour
bone was exposed
augmentation butdone
were symmetrical
to andthe
maintain satisfactory
alveolar during
bone the smile. The
dimensions. Pro-
gingival contour was exposed but symmetrical and satisfactory during the smile. The final
final
Medicina 2023, 59, x FOR PEER REVIEW preparation of
visional restoration the abutments
was made was performed with a heavy chamfer finish line,
5 and
of 11
preparation of the abutments wastoperformed
restore the aesthetics
with a heavy and function
chamfer finishtemporarily. Com-
line, and zirconia
zirconia ceramic
plete healing restorations
was achieved were
afterfor used
six the
months.for the prosthodontic
As expected, rehabilitation
the results obtained (Figure
were 6).
ceramic restorations were used prosthodontic rehabilitation (Figure 6). Thestable.
bite
The
The bite template
gingival was
contour used
was to reestablish
exposed but the vertical
symmetrical dimension.
and The
satisfactory color
during of
template was used to reestablish the vertical dimension. The color of the restorations was the
the restora-
smile. The
tions
final was B1 (Vita
preparation Classical
of the shade
abutments
B1 (Vita Classical shade guide). guide).
was performed with a heavy chamfer finish line, and
zirconia ceramic restorations were used for the prosthodontic rehabilitation (Figure 6).
The bite template was used to reestablish the vertical dimension. The color of the restora-
tions was B1 (Vita Classical shade guide).

(a) (b) (c) (d) (e)

Figure 6. The
Figure 6. The steps
steps of the prosthodontic
of the prosthodontic rehabilitation:
rehabilitation: (a)
(a) Final
Final aspect
aspect of
of the abutment after
the abutment the
after the
healing period; (b) One-step impression with A silicone—Variotime Heavy Tray and Medium Flow
healing period; (b) One-step impression with A silicone—Variotime Heavy Tray and Medium Flow
(Zhermack); (c) The zirconia frame on the master cast; (d) The try-in of the zirconia frame; (e) The
(Zhermack); (c) The zirconia frame on the master cast; (d) The try-in of the zirconia frame; (e) The
final restoration after cementation.
final restoration after cementation.
After the extraction of teeth 15 and 17, two implants were inserted. The osteointegra-
tion of the implants can be seen in the panoramic X-ray after six months (Figure 7).
 (a) (b) (c) (d) (e)
(a) (b) (c) (d) (e)
Figure 6. The steps of the prosthodontic rehabilitation: (a) Final aspect of the abutment after the
Figure 6. The steps of the prosthodontic rehabilitation: (a) Final aspect of the abutment after the
healing period; (b) One-step impression with A silicone—Variotime Heavy Tray and Medium Flow
healing period; (b) One-step impression with A silicone—Variotime Heavy Tray and Medium Flow
(Zhermack); (c) The zirconia frame on the master cast; (d) The try-in of the zirconia frame; (e) The
(Zhermack); (c) The zirconia frame on the master cast; (d) The try-in of the zirconia frame; (e) The
Medicina 2023, 59, 197 final restoration after cementation. 5 of 11
final restoration after cementation.

After the extraction of teeth 15 and 17, two implants were inserted. The osteointegra-
After the extraction of teeth 15 and 17, two implants were inserted. The osteointegra-
tion of the implants can be seen in the panoramic X-ray after six months (Figure 7).
tion
Afterthe
of theimplants can
extraction of be seen
teeth 15in the17,
and panoramic X-raywere
two implants afterinserted.
six months
The(Figure 7).
osteointegra-
tion of the implants can be seen in the panoramic X-ray after six months (Figure 7).

Figure 7.7. Panoramic

Panoramic X-ray with the osseointegrated implants and and
the maxillary prosthodontic reha-
Figure
Figure 7. PanoramicX-ray
X-raywith
withthe
the osseointegrated implants
osseointegrated implants themaxillary
and the maxillary prosthodontic
prosthodontic reha-
bilitation on the natural teeth.
rehabilitation
bilitation ononthe
thenatural
naturalteeth.
teeth.

Pre-prosthetic treatments
Pre-prosthetic treatments were
were performed on
performed the
on on lower arch
thethe
lower arch during
during the
the upper
upper arch
arch
Pre-prosthetic treatments were performed lower arch during the upper arch
healing period.
healing period. The endodontic
TheThe
endodontic retreatments
retreatments of the
of the lower
lower premolars
premolars were
were successful.
successful. The
The
healing period. endodontic retreatments of the lower premolars were successful. The
preparation of
preparation of the
the teeth
teeth was
was carried
carried out
out with
with aa subgingivally
subgingivally placed
placed heavy
heavy chamfer
chamfer finish
finish
preparation of the teeth was carried out with a subgingivally placed heavy chamfer finish
line. Single
Single crown
crown zirconia ceramic restorations and a
line. Single crown zirconia ceramic restorations andbridge were
a bridge realized,
were preserving
realized, preserving
tooth vitality in all abutments (Figure
(Figure 8).
8).
tooth vitality in all abutments (Figure 8).

(a) (b) (c) (d) (e)

(a) (b) (c) (d) (e)
Figure 8. The steps of the prosthodontic rehabilitation: (a) The prepared abutments with the first
Figure 8. The
Figure steps
8. The of the
steps prosthodontic
of the prosthodonticrehabilitation: (a) (a)
rehabilitation: TheTheprepared abutments
prepared with
abutments thethe
with firstfirst
impression cord; (b) One step impression with A silicone; (c) The zirconia frame on the master cast;
impression cord;
impression (b) (b)
cord; OneOnestepstep
impression with
impression A silicone;
with (c) The
A silicone; zirconia
(c) The frame
zirconia on on
frame thethe
master cast;
master cast;
(d) The try-in of the zirconia frame; (e) The final restoration after cementation.
(d) (d)
TheThe try-in
try-in of the
of the zirconia
zirconia frame;
frame; (e) The
(e) The finalfinal restoration
restoration afterafter cementation.
cementation.

For the restoration of the edentulous space on the lower arch, implant therapy was
applied. Two implants were inserted.
In the case of the upper arch, a screw-retained titanium-based zirconia ceramic bridge
was realized after the osseointegration period. The closed impression tray technique was
used (Figure 9).
A panoramic X-ray was taken to verify the osseointegration of the lower implants
(after six months) (Figure 10).
Due to the lack of parallelism of the implant bodies, a cemented zirconia ceramic
bridge was realized to re-establish the function on the lower arch. In this case, the open-tray
technique was used for the impression (Figure 11).
The final aspect of the complex, multidisciplinary full-mouth rehabilitation is pre-
sented in Figure 12.
 applied. Two implants were inserted.
used
In (Figure
the case9).
of the upper arch, a screw-retained titanium-based zirconia ceramic bridge
was realized after the osseointegration period. The closed impression tray technique was
For the restoration of the edentulous space on the lower arch, implant therapy was
used (Figure 9).
applied. Two implants were inserted.
Medicina 2023, 59, 197 In the case of the upper arch, a screw-retained titanium-based zirconia ceramic bridge
6 of 11
was realized after the osseointegration period. The closed impression tray technique was
used (Figure 9).

(a) (b) (c) (d) (e)

(a) (b) (c) (d) (e)

(a) (b)(f) (c)(g) (h)

(d) (e)
Figure 9. The sequences of the implant-prosthodontic therapy in the maxilla: (a) The emergence
profile after the removal of the healing caps; (b) The impression copings in the mouth; (c) The
(f)transfer caps applied on the(g)impression copings; (d) The (h) master cast with the artificial gingiva and
titanium abutments; (e) The zirconia frame on the master
Figure 9. The sequences of the implant-prosthodontic therapy cast; (f)in
The intraoral
the maxilla:try-in of the
(a) The titanium
emergence
abutments; (g) The intraoral try-in of the zirconia frame; (h) The final restoration
profile after the removal of the healing caps; (b) The impression copings in the mouth; (c) Theafter the intraoral
(f)fixation.
transfer caps applied on the (g)impression copings; (d) (h) The master cast with the artificial gingiva and
titanium
Figure 9.abutments; (e) The
The sequences zirconia
of the frame on the master
implant-prosthodontic cast; (f)
inThe
the intraoral
maxilla: try-in
(a) Theofemergence
the titanium
Figure A The
9.
abutments; panoramic
(g)sequences
The X-ray
of the
intraoral was
try-in taken
implant-prosthodontic
of the zirconia thetherapy
to verifyframe; osseointegration
therapy
(h) The in
final of the
therestoration
maxilla: lower
(a)after
Thethe implants
emergence
intraoral
profile after the removal of the healing caps; (b) The impression copings in the mouth; (c) The
(after
profile sixthe
after
fixation. months)
removal (Figure
of the 10). caps; (b) The impression copings in the mouth; (c) The transfer
healing
transfer caps applied on the impression copings; (d) The master cast with the artificial gingiva and
caps applied
titanium on the impression
abutments; copings;
(e) The zirconia frame(d)onThe
themaster
mastercast
cast;with theintraoral
(f) The artificialtry-in
gingiva and
of the titanium
titanium
A panoramic
abutments;
abutments; (e)
(g)The X-rayframe
Thezirconia
intraoral was
try-in taken
onofthe to verify
themaster cast;
zirconia the osseointegration
(f) The
frame; (h)intraoral
The finaltry-in ofof
thethe
restoration lower
titanium
after implants
the abutments;
intraoral
(after
Thesix
fixation.
(g) months)
intraoral (Figure
try-in 10).
of the zirconia frame; (h) The final restoration after the intraoral fixation.

A panoramic X-ray was taken to verify the osseointegration of the lower implants
(after six months) (Figure 10).

Figure 10. Panoramic X-ray with the osseointegrated implants on the lower arch and the good
marginal adaptation of all the restorations.

Due to the lack of parallelism of the implant bodies, a cemented zirconia ceramic
Figure
bridge
Figure 10.was
10. Panoramic X-ray
realizedX-ray
Panoramic with the
the osseointegrated
to re-establish
with osseointegrated implants
the function onimplants on arch.
the lower
on the lower
the lower arch
In this andthe
case,
arch and theopen-
the good
good
marginal adaptation
tray technique wasof all
used the restorations.
marginal adaptation of all thefor the impression (Figure 11).
restorations.
Figure 10. Panoramic X-ray with the osseointegrated implants on the lower arch and the good
Due to the lack of parallelism of the implant bodies, a cemented zirconia ceramic
marginal adaptation of all the restorations.
bridge was realized to re-establish the function on the lower arch. In this case, the open-
tray technique
Due to thewas
lackused for the impression
of parallelism (Figurebodies,
of the implant 11). a cemented zirconia ceramic
bridge was realized to re-establish the function on the lower arch. In this case, the open-
tray technique was used for the impression (Figure 11).
Medicina 2023, 59, x FOR PEER REVIEW 7 of 11

(a) (b) (c) (d) (e)

(a) (b) (c) (d) (e)

(a) (b) (c) (d) (e)

(f) (g) (h) (i) (j)
Figure 11. The sequences of the implant-prosthodontic therapy in the mandible: (a) The healing
Figure 11. The sequences of the implant-prosthodontic therapy in the mandible: (a) The healing caps;
caps; (b) The impression copings in the mouth; (c) The try-in of the open tray; (d) The impression
(b) The
with the impression copings
technical analogs (e)inThe
theprepared
mouth; (c) The try-in
abutments andof the
the artificial
open tray; (d) The
gingiva onimpression
the master with
cast; the
technical
(f) analogs
The zirconia (e) The prepared
framework abutments
on the cast.; (g) The and
finalthe artificialon
restoration gingiva on (h)
the cast; the The
master cast;
try-in of (f)
theThe
zirconiaframe;
zirconia framework on the
(i) Closing thecast.;
hole (g) Theabutments;
on the final restoration
(j) The on the
final cast; (h) The
restoration aftertry-in of the zirconia
the cementation.
frame; (i) Closing the hole on the abutments; (j) The final restoration after the cementation.
The final aspect of the complex, multidisciplinary full-mouth rehabilitation is
presented in Figure 12.
 Figure 11. The sequences of the implant-prosthodontic therapy in the mandible: (a) The healing
caps; (b) The impression copings in the mouth; (c) The try-in of the open tray; (d) The impression
with the technical analogs (e) The prepared abutments and the artificial gingiva on the master cast;
(f) The zirconia framework on the cast.; (g) The final restoration on the cast; (h) The try-in of the
zirconia frame; (i) Closing the hole on the abutments; (j) The final restoration after the cementation.
Medicina 2023, 59, 197 7 of 11
The final aspect of the complex, multidisciplinary full-mouth rehabilitation is
presented in Figure 12.

(a) (b)

(c)
Figure
Figure 12.
12. The
The final
final result
result of
of the
the full-mouth
full-mouth rehabilitation:
rehabilitation: (a)
(a) Intraoral
Intraoral aspect
aspect of
of the
the restorations;
restorations;
(b) The improved smile with minimal gingival display; (c) Panoramic X-ray after
(b) The improved smile with minimal gingival display; (c) Panoramic X-ray after one year.one year.

3. Discussion
3. Discussion
Several studies
Several studies have
have demonstrated
demonstrated the the need
need for
for these
these surgical
surgical interventions
interventions to
to obtain
obtain
an aesthetic
an aesthetic smile,
smile, predominantly
predominantly in in the
the case
case of
of female
female patients
patients [16],
[16], as
as in
in the presented
presented
case. The
case. The patient’s
patient’s initial
initial problem
problem was was the
the gingival
gingival smile
smile with
with the
the visibility
visibility of
of unaesthetic
unaesthetic
metal-ceramic prosthetic works. In this situation, resolving the patient’s problems
metal-ceramic prosthetic works. In this situation, resolving the patient’s primary primary
was possible
problems wasonly by performing
possible full-mouthfull-mouth
only by performing rehabilitation.
rehabilitation.
The surgical
The surgicalcorrection of the
correction ofupper clinical crown:root
the upper ratio and gingival
clinical crown:root ratio anddisplacement
gingival
was necessarywas
displacement before the prosthodontic
necessary approach.
before the prosthodontic approach.
According to
According to Narayan
Narayan et et al.,
al., the
the pretreatment
pretreatment planning
planning included
included aa complex
complex clinical
clinical
evaluation regarding:
evaluation regarding:
•• The patient’s
The patient’s systemic
systemic health
health and
and her
her expectations;
expectations;
•• The evaluation of the face and smile
The evaluation of the face and smile line; line;
•• The lip
The lip thickness
thickness and
and size;
size;
•• The size and shape of
The size and shape of the the teeth;
teeth;
•• The gingival biotype and the
The gingival biotype and the width width of
of keratinized
keratinized gingiva;
gingiva;
•• The thickness and contour of the alveolar bone
The thickness and contour of the alveolar bone [17]. [17].
CBCT evaluation was performed by measuring the existent and the future crown: root
ratio and the crestal bone relation to the cementoenamel junction to decide the surgery type.
In the presented case a, mock-up guided crown lengthening procedure was performed
based on the diagnostic wax-up, similar to the technique described by Jurado et al. [18] in
their case report. Using a precise 3D-printed surgical guide for crown lengthening can help
to prevent or reduce the chance of under or over-contouring hard and soft tissues during
the procedure [19].
The crown-lengthening surgery combined two modern, minimally invasive techniques
(laser therapy for soft tissue remodeling and piezo-surgery for bone resection) and the con-
ventional technique to obtain long-lasting results with minor post-interventional symptoms
and reduced healing time. The methods reduced surgical chair time and operative trauma,
accelerating the healing process and making the patient more comfortable. The flapless
surgery was undesirable because it did not allow direct visualization of the operative
field and can be challenging regarding soft tissue damage [20]. Performing a reduced flap
without vertical incisions was beneficial.
Medicina 2023, 59, 197 8 of 11

The thick gingival phenotype of the patient facilitated the healing process. Three
months post-operatively, stabile results were obtained, probably due to minimally invasive
techniques and the favorable gingival phenotype. The recovery period, a controversial topic
in the literature, can differ individually. After soft tissue remodeling, the final rehabilitation
can be done after a healing period of three months [21,22]. According to Herrero et al.,
in the case of bone remodeling with biological width modification, the healing period
must be about six months before the prosthodontic rehabilitation [23], and it is essential to
define a proper distance between the finish line and the bone margin during post-surgical
prosthodontic treatment [24]. In our case, the healing period was six months.
After this period, the re-preparation of the teeth was carried out with a subgingivally-
placed heavy chamfer finish line at a greater distance from the bone margin than 5 mm. Zir-
conia ceramic single crown restorations and bridges were used for aesthetic and functional
rehabilitation. Several studies have been carried out regarding the marginal adaptation of
these restorations, which are superior to conventional metal-ceramics [25,26]. Proper teeth
preparation and a good impression technique are essential to achieve the best results [27,28].
In the case of digital workflow during the zirconia frame’s design, the cementation space
can influence the quality of the marginal adaptation. Defining the dimensions of this space
must be done with caution [29]. Dittmer et al. [30] and Kohorst et al. [31] demonstrated
in their studies that the successive application and firing of ceramic layers on the zirconia
frame could cause marginal discrepancies, contradictory to Vigolo et al. findings [32]. The
zirconia framework presents a lower occurrence of discrepancies than metal-ceramics [33];
this can contribute to obtaining long-lasting aesthetical results. The perfect marginal fit of
the restorations is essential in maintaining periodontal health and ensuring the restorations’
natural appearance, especially in the frontal area.
In the literature, different recommendations can be found for the cementation of
zirconia ceramic restorations on teeth and implants. Some studies recommend the adhesive
cementation technique in case of poor retention of the abutments [34,35]. Other studies
have shown the importance of treating the inner surfaces of zirconia restorations to achieve
good adhesion after cementation [36,37]. In the presented case, the zirconia restoration
internal surface was sandblasted and treated with Ivoclean (Ivoclar). The vitality of the
teeth influenced our choice of adhesive material. The adhesive cementation was abandoned
to avoid pulpal irritation related to etching. Resin-modified glass ionomer cement was
used for the final cementation of the restorations in the case of natural teeth.
In the case of implants, the fixation method (screw or cement retained) of the restora-
tions might not directly influence their survival rate. However, it can lead to certain
complications (mainly periimplantitis) [38]. Each retention method has its indication
with advantages and disadvantages [39]. According to de Brandao et al., there is no ev-
idence of differences in the marginal bone loss around the cement and screw-retained
restorations [40]. Several studies demonstrated a higher success rate of screw-retained
restorations versus classically cemented ones [38,41]. Park et al. recommend choosing the
appropriate fixation method depending on the implants’ parallelism and considering the
occlusal relations. It is crucial in the case of the upper premolar region the possibility to
place the access hole of the screw on the central fossa [42], as it was in our case.
The patient was satisfied with the obtained results, even though she still had a moder-
ate gummy smile. The lip-repositioning surgery represents future possibilities for better
aesthetical results [43], as does the injection of botulinum toxin A [44].
The patient chose a less invasive way to improve the final aesthetics in the future by
using hyaluronic acid filler to make the lips look fuller and more youthful.
The limitations during the follow-up:
• Lack of periodical CBCT evaluation (at three months, six months, and one year)
• Lack of periodical periodontal evaluation using periodontal probing.
Digital planning and using a 3D-printed surgical guide can improve the expected
results. A good collaboration between a multidisciplinary dental team and a facial plastic
surgeon can result in even better aesthetics.
Medicina 2023, 59, 197 9 of 11

4. Conclusions
The crown-lengthening surgery is an efficient method to improve aesthetics in the
case of a gingival smile. Laser therapy and piezo-surgery are modern methods that allow
minimally invasive and efficient interventions with fast postoperative recovery. The zirco-
nia ceramic restorations can be used to restore aesthetics and function with good results.
Screw-retained restorations have a better long-term prognosis compared to cemented ones,
demonstrated by the one-year follow-up Panoramic X-ray.

Author Contributions: Conceptualization: K.M.J.; methodology: K.M.J. and F.D.B.; formal analysis:
A.S. and A.K.; investigation: I.M.; resources: L.G.H.; data curation: A.I.A.; writing—original draft
preparation: K.M.J., F.D.B. and A.I.A.; writing—review and editing: K.M.J.; visualization: D.C.;
supervision: D.C. All authors have read and agreed to the published version of the manuscript.
Funding: This research received no external funding.
Institutional Review Board Statement: The case report was conducted according to the guidelines of
the Declaration of Helsinki on experimentation involving human subjects, as revised in 2013. Ethical
review and approval were waived due to the design of the present case report. Our Institutional
policy does not require the Ethical Committee approval in this case as the patient signed the informed
consent requested for the publication of the present case report. Ethical approval was not sought for
the present case report also because no experimental procedures were performed during the patient’s
treatment, and none of the materials or equipment used were prototypes. All of them are available
on the market in their current form, and they were used according to the manufacturer‘s instructions
without requiring off-label protocols.
Informed Consent Statement: Informed consent was obtained from the patient. Written informed
consent has been obtained from the patient to publish this paper.
Data Availability Statement: The dataset analyzed during this case report are available from the
first author on request.
Acknowledgments: The authors declare no financial affiliation or involvement with any commercial
organization with a direct financial interest in the materials discussed in this manuscript.
Conflicts of Interest: The authors declare no conflict of interest.

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