Case presentation :
A 26-year old male patient was referred to the Outpatient and Implantology department of the university dental clinic of monastir. He was non-smoker and the medical history did not reveal any significant systemic diseases.
The chief-complaint was the replacement of the right upper first molar (tooth 16) which was extracted 5 years ago due to dental decay.
Clinically, no horizontal defect was objectified, the present prosthetic space and keratinized tissue were sufficient. An OPG and a CBCT were prescribed and showed a severe vertical defect with a residual ridge height of 2mm.
Moreover, on the inner side of the lateral wall of the maxillary sinus, an osteoma was fortouisly discovered. It had a corono apical long axis of 8 mm and a mesiodistal width of 5mm. (Fig 1, Fig 2)
This benign tumor was completely asymptomatic, but it was located in the site of the missing tooth and would certainly interfere with the lateral window design required in the intended bone augmentation procedure.
Sinus-graft with the lateral approach and delayed implant placement was decided. The patient was informed and consent was obtained.
After an initial mouth rinse with chlorhexidine digluconate 0.2%, local anesthesia was carried using mepivacaïne 2% with epinephrine 1 :100,000 (médicaïne® 2%, Médis, Tunisia).
A crestal incision in the edentulous site, completed with an instrasulcular incision regarding tooth 17 and a releasing incision distal to tooth 15 enabled the relflexion of a full-thickness triangular flap with a sufficient visual access to the surgical site.
The excision of the lateral window, along with the part of the osteoma that impeded on it, was performed using piezoelectric instruments (Mectron®) in order to minimize the risk of perforation of the schneiderian membrane (Fig 3.a). The remaining part of the osteoma was kept in place.
The sinus membrane was elevated and a first resorbable membrane was placed beneath it to reinforce it and prevent a possile leak of the bone particles into the antrum (Fig 3.b ; 3.c).
A xenograft (Apatos - OsteoBiol ®) was condensed to fill the antral cavity (Fig 3.d). The site was then covered with a second resorbable membrane and the flap was repositioned and sutured. (Fig 3.e)
A post-operative retroalveolar radiography was immediately taken (Fig 3.f). An association of amoxicillin/clavulanic acid (1g every 8 hours for 10 days) was prescribed post-operatively. Sutures were removed after 10 days, and implant placement was programmed in 6 months (Fig 3.g)