Endoscopic-Assisted Sinus Floor Augmentation Combined With Removal of an Antral Pseudocyst of the Ipsilateral Maxillary Sinus

Treatment of Mucous Retention Cyst in Association with Sinus Lift and Implant Placement: A Case Report with 1-Year Follow-Up

Sinus lift augmentation techniques, lateral or crestal approaches, have been well documented, with bone substitute graft, or without bone material, with immediate or delayed implant placement as a treatment option for the atrophic maxilla in the posterior area. However, the sinus lift procedures performed in the presence of cysts, mucoceles, mucous retention cysts (MRCs), and antral pseudo-cysts could mainly decrease the sinus cavity volume and could increase the possibility of ostium obstruction and might lead to infection followed by failure of the grafting procedure. A radiological assessment should be made with computerized tomography (CT) or cone-beam CT to evaluate the remaining bone volume and to detect any pathology in the sinus. Different techniques were described in the literature for sinus lifting and bone grafting in patients with cysts. For some authors, cysts should be treated before sinus grafting and six months later, the procedure could be performed. For others, sinus lifting can be performed without lesion removal. At this time, controversy exists regarding the decision on whether lesions must be removed/aspirated or not before sinus grafting. In this study, we report a case where an MRC was aspirated and instantaneously, the sinus membrane was lifted and grafted, and implants were installed with 1-year follow-up after loading. Identifying lesions in the maxillary sinus is essential before planning any type of sinus augmentation and implant placement.

Maxillary Antral Pseudocyst Drift after Osteotome Sinus Floor Elevation with Simultaneous Implant Placement: A Case Report and Literature Review

This report describes maxillary antral pseudocyst drift after maxillary sinus floor augmentation through osteotome sinus floor elevation with simultaneous implant placement. 3D Slicer was used to measure the pseudocyst and maxilla for the placement of the implants; follow-up visits were scheduled at 6, 12, and 22 months. No adverse effects were observed during or after surgery, and all implants exhibited osseointegration without mobility. At 6 months after surgery, the pseudocyst had moved posterolaterally from the preoperative position near the anterior medial maxillary sinus, then returned to its original position at 12 months. However, it had remigrated to the posterolateral position at 22 months. The preoperative volume of the pseudocyst was 3.795 mm³; it was 2.370, 3.439, and 2.930 mm³ at 6, 12, and 22 months after surgery, respectively. The changes in pseudocyst drift and volume did not have a substantial negative influence on the implants, presumably because of cystic attachment and the recurrence of multiple pseudocysts at different locations. The risks associated with changes in a pseudocyst can be avoided, if an appropriate treatment plan is selected.

Maxillary sinus floor augmentation comparing removing versus retaining antral pseudocyst: A retrospective cohort study

OBJECTIVES

To retrospectively compare multilevel volumetric changes in both hard and soft tissues between antral pseudocyst (AP) removal and retainment before maxillary sinus floor augmentation (MSFA) and immediate implant placement.

MATERIAL AND METHODS

Twenty-six patients with thirty-eight implants placed from 2016 to 2021 were included and divided according to a cohort design as follows: 13 removing the cyst (RC group) and 13 "leaving alone" the cyst (LC group). 3D radiographic parameters (primary outcome), 2D parameters and clinical records (secondary outcome) involving both hard and soft tissues were evaluated for 4 periods (T1: immediate postoperative, T2: 6-month, T3: 12-month, and T4: 2- to 5- year follow-up). Possible confounding factors, including sinus anatomical features and implant distribution, were also analyzed to eliminate their disturbance.

RESULTS

The 3D volumetric change rate of bone grafts in the RC group (-9.32 ± 10.01%) from T2 to T3 was significantly lower than that in the LC group (-19.8 ± 10.59%) (p < .05). The change rate of apical bone height (ABH), endo-sinus bone gain (ESBG) and other 2D parameters were not significantly different between the two groups. 5.3% implants in RC group and 9.1% implants failed during follow-ups. 0% postoperative complications were observed in RC group. The Schneiderian membrane of RC group was significantly thinner than that of LC group at two measuring points in sinus.

CONCLUSION

The present study demonstrated that compared to AP retainment, AP removal before MSFA and immediate implant placement can obtain higher bone graft volumetric stability and favorable prognosis. The study protocol was approved by the Medical Ethics Committee of the Affiliated Hospital of Stomatology, School of medicine, Zhejiang University, China (Acceptance number: 2021-117(R)).

Prevalence of and factors associated with maxillary sinus cyst in a Chinese population

PURPOSE

This study used cone-beam computed tomography (CBCT) to assess the prevalence of and factors associated with maxillary sinus cysts (MSCs) in a Chinese population.

METHODS

A total of 2,571 CBCT scans of 5,000 sinuses were analyzed. MSCs were diagnosed on the basis of imaging features within the maxillary sinus. Sex, age, dental condition, and anatomic condition were assessed. Associations with these factors were evaluated with logistic regression and a generalized estimating equations model.

RESULTS

The prevalence of MSCs was 15.46% at the sinus level and 23.44% at the patient level. The prevalence of MSCs was higher for men (OR = 1.864, P < 0.001) and for patients with apical lesions (OR = 1.76, P < 0.001), severe bone loss (OR = 1.363, P < 0.05), tooth roots in contact with the sinus floor (OR = 1.68, P < 0.001), and pits or septa on the floor of the maxillary sinus (OR = 1.539, P < 0.001).

CONCLUSION

This large sample had a high prevalence of MSCs. MSC prevalence was associated with multiple factors, including sex, dental condition, and anatomic condition. Maintenance of healthy dental and periodontal status might help prevent MSCs.

Are mucous retention cysts and pseudocysts in the maxillary sinus a risk factor for dental implants? A systematic review

Background

Mucous retention cysts and pseudocysts of the maxillary sinus are benign lesions present in up to 13% of adult patients. Different surgical approaches for sinus lift and dental implant placement in the presence of these lesions have been proposed.

Material and Methods

A systematic review was performed following the PRISMA statement recommendations to answer the PICO question: Does the aspiration or removal of mucous retention cysts/pseudocysts before or during sinus lifting and dental implant placing, affect the survival of the implants? The study was pre-registered in PROSPERO (CRD42020185528). Included articles quality was assessed using the “NIH quality assessment tool” and “The Newcastle-Ottawa scale”.

Results

Previous literature in this field is scarce and with a low level of evidence. There are no randomized prospective studies. Only 19 studies were identified, being composed of 2 cohort studies and 17 case series/reports. These studies involved 182 patients with a previous history of mucous retention cyst or pseudocyst in 195 maxillary sinuses where 233 implants were placed. The mean age of the patients was 45.5 (range: 12-80 years); 122 (67%) were male patients and 60 (33%) were female patients. The mean follow-up of the patients was 17.6 (range: 4-90 months). Only two fail was reported. No differences were identified in relation to the surgical approach or in relation to the removal/aspiration of the sinus lesion (prior to or simultaneous to sinus grafting) or not.

Conclusions

The level of evidence was grade 4 according to the CEBM and further studies are needed to confirm this observations, but with the available data, dental implants placement after sinus lift procedure in patients with mucous retention cysts and pseudocysts seems to be safe and present high survival regardless on the removal of the lesion or not.

Key words:Dental implants, maxillary sinus, sinus lift, mucous retention cyst, pseudocyst.

Endoscope-controlled maxillary sinus floor elevation: a review of the literature

A systematic review of the literature was conducted to assess the safety and efficacy of endoscope-assisted maxillary sinus elevation. PubMed, Embase, Web of Science, and the Cochrane database were searched for articles in English. Published studies involving patients who had undergone endoscope-assisted maxillary sinus floor augmentation were selected. The validity of the included articles was evaluated. After going through full texts, a total of 12 studies met the eligibility criteria and were included. It was concluded that endoscope-controlled maxillary sinus floor elevation was a viable and beneficial method, providing direct visualisation of the integrity of the mucosa and placing of bone graft material. The endoscope could be inserted into the maxillary sinus lumen, subantral space below the Schneiderian membrane, or through the alveolar crest. With the endoscope, perforations can be detected and managed precisely. However, high-quality clinical trials are still needed to validate the predictability and advantages of this surgical procedure.

Endoscopic Approach to Remove a Dental Implant With Simultaneous Laser-Cystectomy

BACKGROUND

Removal of dental implants from the maxillary sinus may require surgical treatment of comorbidities.

METHOD

Canine fossa endoscopy with an additional laterobasal access originally has been used for flapless sinus floor augmentation. The combined technique is presented to remove a titanium screw from the maxillary sinus. The same portals served for dissection of a mucocele using a diode laser.

CONCLUSIONS

The combination of canine fossa endoscopy and laterobasal access allows an appropriate instrumentation and triangulation of the scope for the endoscopically assisted implant removal and dissection of the mucocele.