Stage 4 – Surgical procedure
Surgery was performed under local anesthesia [Fig. 10](11) and
inhalation sedation with permanent monitoring of vital functions, after
a complete pre-opperative evaluation by the AIC (anesthesia and intensiv
care) doctor. The patient was instructed to administer himself orally
amoxicillin 875 mg + clavulanic acid 125 mg every 12 hours for two days
prior to surgery.
A crestal incision was performed from tuberosity to tuberosity, with one
relieving incision in the midline. Buccal and palatal flaps were raised,
exposing the anterior nasal spine, the pyriform apertures, the canine
fossae, the zygomatic buttresses and the posterolateral maxillae.
Drawing the incision line must be done with a firm movement (for a good
elevation of the mucoperiosteum), thus offering increased comfort to the
clinician during the medical procedure, by the fact that the bleeding is
minimal, a good post-operative healing is ensured (dehiscences are
avoided, which at least in the case subperiosteal implant represents an
element that can compromise its integrity).
In cases with severe bone atrophy, we can meet two types of mucosae: 1)
residual hypertrophic mucosa, with low resilience, very loose, which
must be adjusted intraoperatively becuase it has poor vascularity and is
very reactive or 2) residual thin mucosa, which can cause difficulties
in rounding the edges of the wound. In this case, the mucosae has been
reduced during surgery.
The next step after elevating the flap is represented by the placement
of the implant itself, after this was removed from the sterile storage
box [Fig. 13](11). The implant has a position of maximum intimacy
with the residual alveolar bone, intimacy that must be followed,
identified and exploited.
The first ostheosynthesis screws that are fixed are those at the
extremities of the implant. The initial tightening is not definitive,
but gradually, manually.
The flap was closed through multiple single knot ties [Fig. 16](11)
done with a synthetic suture, manufactured by polymerising propylene
[Fig. 15] (10). The suture is hydrophobic, it absorbs practically no
water and is chemically inert. It ensures excellent know security and
has a consistently high tear resistence, property which helps us prevent
the dehiscences. It is ideal for skin or mucosa suture, where an
excellent cosmetic result is critical (6).
Prosthetic impressions were taken immediately after closure, and
prosthesis was successfully adapted in the same day, prior to patient
discharge. Patient’s old removable denture was used as a provisional,
and was padded in office. Thus, the patient being used to it, a much
easier transition was endured. After it has been adapted and the
abutments were placed, the denture was temporarilly cemented.
Discussion
In the last decades, although a decrease in the number of edentulous
patients could be observed, their number still remains high, and with
the increase in life expectancy, their need to replace lost teeth also
rises. Furthermore, studies show that 1 out of 5 seniors aged 65 or more
lost all his teeth. These being said, clinicians must offer viable
treatment solutions to patients’ problems.
Endosseous implants have been and still are a suitable solution for
those missing teeth, but unfortunatelly in cases with severe bone
atrophy they have their limitations. As an alternative, more that 50
years ago, the subperiosteal implant was designed to fulfill this acute
need for bone support and has been used ever since. However, the
subperiosteal implants were soon surrounded by multiple complications
such as implant exposure/woond dehiscences, implant mobility/implant
loss, lack of intimacy with the bone due to impression material
instability, and of course their popularity decreased. Recently,
dentistry has been going through a digital revolution. It’s all about
digital acquisition, better software, and more advanced fabrication.
It’s the start of a whole new world of fixed prosthetics, including
custom implant therapy.
In their study, Cerea and Dolcini described a group of 70 patients who
had received custom-made titanium subperiosteal implants made using
direct metal laser sintering (DMLS), which demonstrated a survival rate
of 95.8% and low complication rates over a 2-year follow-up period.
They came to the conclusion that when endosseous implants could not be
placed, custom-made DMLS subperiosteal implants could offer a viable
alternative treatment method for prosthetic restoration of severely
atrophic jaws (7,8).
Conclusion
Althought subperiosteal implants are no longer the only option to
restore atrophic jaws, they still remain a less invasive solution. Their
high success rates and predictability remain undisputed advantages and,
along with the technological evolution and the imprint left by the
digital revolution even the worst disadvantages are losing ground, so
that the treatment period was reduced from two surgical interventions to
only one and thus the physical trauma inflicted on the patient is
minimal. By using digital technology, the clinician has the opportunity
to foresee the final result of the treatment plan, to realize the design
of the future implant based on a 3D model of the patient’s anatomy, thus
reducing almost to a minimum the possibility of error in execution. The
important aspects that the clinician must continue to pay attention to
are the healing stage and the complications associated with
subperiosteal implants: dehiscences, implant mobility, framework
fracture. These being said, the clinician’s skills to propose, design
and place a subperiosteal implant remain and for sure will be an
important asses in any ideal treatment plan.
References
- Ioan Sîrbu, DDS (DMSc); Subperiosteal Implant Technology: Report
from Rumania . J Oral Implantol 1 August 2003; 29 (4): 189–194
- Garrido-Martínez P, Quispe-López N, Montesdeoca-García N,
Esparza-Gómez G, Cebrián-Carretero JL. Maxillary reconstruction with
subperiosteal implants in a cancer patient: A one-year follow-up. J
Clin Exp Dent. 2022 Mar 1;14(3):e293-e297. doi: 10.4317/jced.59331.
PMID: 35317297; PMCID: PMC8916599.
- Lopes LF, da Silva VF, Santiago JF Jr, Panzarini SR, Pellizzer EP.
Placement of dental implants in the maxillary tuberosity: a systematic
review. Int J Oral Maxillofac Surg. 2015 Feb;44(2):229-38. doi:
10.1016/j.ijom.2014.08.005. Epub 2014 Sep 26. PMID: 25260833.
- https://www.treatstock.co.uk/machines/item/220-eosint-m-280
accesat: 02.10.2023
- Resnik R. Misch’s Contemporary Implant Dentistry . 4th ed. St.
Louis: Mosby; 2021
- https://www.resorba.com/ accesat: 09.10.2023
- Ângelo DF, Vieira Ferreira JR. The Role of Custom-made Subperiosteal
Implants for Rehabilitation of Atrophic Jaws - A Case Report. Ann
Maxillofac Surg. 2020 Jul-Dec;10(2):507-511. doi:
10.4103/ams.ams_263_20. Epub 2020 Dec 23. PMID: 33708606; PMCID:
PMC7943994.
- Cerea M, Dolcini GA. Custom-made direct metal laser sintering titanium
subperiosteal implants: A retrospective clinical study on 70
patients. BioMed Res Int. 2018;2018:11
- Link: https://www.ab-dent.com/u-product/
- Link: https://resorba.com/region/row/product/sutures/mopylen-cv/
- Courtesy of Prof. Ioan Sirbu, surgery day.
- Dicom images from the CBCT of the pacient realized one month before
the surgery
- STL images from AB Dental International design of the future implant