Long-term effects of sinus membrane perforation on dental implants placed with transcrestal sinus floor elevation: A case-control study

Association between sinus septa and lateral wall thickness with risk of perforation during maxillary sinus lift surgery: A systematic review and meta-analysis

OBJECTIVE

Sinus membrane perforation is a common complication of sinus lift surgery. This review aimed to examine if anatomical factors such as the presence of septa and lateral wall thickness influence the risk of membrane perforation.

METHODS

This study was registered on PROSPERO (CRD42023488259). PubMed, Embase, and Web of Science were searched for relevant studies published up to 26th June 2024. The outcome of interest was the risk of perforation based on presence of septa and lateral wall thickness. Random-effects meta-analysis was conducted with dichotomous data to obtain the odds ratio (OR) of perforation using Review Manager.

RESULTS

Ten studies with 1865 patients undergoing 2168 "lateral" sinus lift procedures were included. The total incidence of Schneiderian membrane perforations was 19% (405 cases). Schneiderian membrane perforation was present in 169/425 cases (39.76%) with sinus septa and 184/1492 cases (12.33%) without septa. Meta-analysis showed that septa were significantly associated with an increased risk of perforation (OR: 4.03 95% CI: 1.77, 9.19) with high heterogeneity (I2 = 87%). The certainty of the evidence was very low. Data on lateral wall thickness and risk of perforation was too heterogeneous for a meta-analysis. Studies reported mixed results on the risk of perforation based on lateral wall thickness.

CONCLUSIONS

Our results show, with very low-quality evidence, that the presence of septa significantly increases the risk of perforations during maxillary sinus lift surgery. Evidence on the association between lateral wall thickness and a risk of perforations during sinus lift surgery is conflicting, and no clear conclusions can be derived at this stage.

Perforating dental implants and maxillary sinus pathology

OBJECTIVES

To study the association between perforation dental implants into the maxillary sinus cavity and the development of sinus pathology.

METHODS

We retrospectively examined 3732 computerized tomography (CT) scans to detect maxillary implants. The detected scans were grouped based on apparent or lack of perforated dental implants in the maxillary sinus (study and control group, respectively). Clinical data was gathered including the CT indication, patients' demographics, comorbidities and medications, implant features, and the radiographic appearance of the maxillary sinuses. We conducted a logistic regression to identify risk factors to develop radiopaque thickening in the sinuses.

RESULTS

Included in the study were 198 patients with 719 maxillary implants; of these, 236 and 483 implants were in the study and control groups, respectively. Sinus opacification was associated with implants' perforations (p < 0.001), diameter, and side and place (p < 0.05). Implants' perforation (OR = 3.679; 95% CI = 1.891-7.157) and diameter (OR = 1.608; 95% CI = 1.067-2.424), sinus floor augmentation (OR = 2.341; 95% CI = 1.087-5.042), male gender (OR = 2.703; 95% CI = 1.407-5.192), and smoking (OR = 6.073; 95% CI = 2.911-12.667) were associated with ipsilateral sinus fullness.

CONCLUSIONS

A first large study on the association between maxillary dental implant and sinus pathology. Dental implant perforation is associated with sinus opacification. Considering dental implant diameter, rather than vertical depth of penetration into the sinus, as an important criterion when examining perforated dental implants necessitates a new approach to clinical decision-making.

Clinical Outcomes of Maxillary Sinus Floor Perforation by Dental Implants and Sinus Membrane Perforation during Sinus Augmentation: A Systematic Review and Meta-Analysis

The aim of the present systematic review was to investigate the clinical outcomes after the perforation of the maxillary sinus by dental implants, or after maxillary sinus membrane perforation during sinus lift procedure. Twenty-nine publications were included. Failure rates of implants in cases where perforation of sinus floor had happened (11 studies) was generally low, and only one case of transient sinusitis was reported. The estimated failure rate of these implants was 2.1% (SE 1.0%, p = 0.035). There were 1817 implants (73 failures) placed in augmented sinuses in which the sinus membrane was perforated and 5043 implants (274 failures) placed in sinuses with no perforated membrane, from 18 studies. The odds of implant failure difference between the groups were not significant (OR 1.347, p = 0.197). log OR of implant failure between perforated and non-perforated membrane groups did not significantly change with the follow-up time (-0.004/month; p = 0.500). In conclusion, implant failure rate is generally low either for implants penetrating in the floor of the maxillary sinus or implants placed in augmented sinuses in which the sinus membrane was perforated. The prevalence of postoperative infection/sinusitis is low, and it may depend either on the dimensions of the perforation or on the anatomical predisposition.

The transalveolar approach with the small segmentation method for inclined maxillary sinus floor elevation: A retrospective study

OBJECTIVE

To evaluate the clinical outcome of the transalveolar approach with the small segmentation method for inclined maxillary sinus floor elevation.

METHODS

Sixty-one patients with an inclined maxillary sinus floor (tilt angle ≥ 10°) and insufficient residual bone height in the posterior maxilla were included and grouped according to the tilt angle of the sinus floor, with group A having patients with the tilt angle ≥ 10° and ≤ 30° and group B having patients with the tilt angle > 30°. After completing sinus membrane elevation and bone augmentation using bone substitute materials, the implants were inserted at the same appointment, and the restoration was completed after 5-6 months of osseointegration. The preoperative sinus floor level and sinus floor elevation achieved postoperatively were assessed and recorded. At pre- and post-operative timepoints, the sagittal plane of the cone beam computed tomography was used to evaluate the bone height changes at the peak, middle and valley points in the slope segment intended for implant implantation.

RESULTS

Osseointegration was evident in all 61 patients, and the final restoration was completed with functional loading. After assessing the normality and homogeneity of variance, two-sample t-test or nonparametric tests were employed to estimate the differences in the bone height changes. The degrees of freedom (df) for this analysis were 59. The elevation attained at the middle point in groups A and B were 6.71 ± 1.38 and 5.75 ± 1.56 mm, respectively, demonstrating a significant difference (p < 0.05). Furthermore, at the peak and valley points, group A exhibited bone height changes of 5.79 ± 1.74 and 6.06 ± 1.45 mm, respectively, compared to group B with changes measuring 4.63 ± 2.18 and 5.58 ± 2.39 mm, respectively, with no significant difference in the two groups (p ≥ 0.05). The prevalence of intraoperative sinus membrane perforation was assessed using the chi-square test. It was found that four cases in group A and five cases in group B experienced sinus membrane perforation, with no significant difference in the two groups (p ≥ 0.05, df  = 1).

CONCLUSION

The transalveolar approach using the small segmentation method suggests a promising approach for elevating the inclined maxillary sinus floor.

Dental implant as a potential risk factor for maxillary sinus fungus ball

Fungus ball is the most common form of non-invasive fungal sinusitis, and maxillary sinus is the most commonly involved site. Maxillary sinus fungus ball (MFB) accounts for a considerable proportion of unilateral maxillary sinusitis. The prevalence of MFB has recently increased; however, its contributing factors are unclear. This study analyzed the association between MFB and dental implants. One hundred one patients who underwent unilateral maxillary sinus surgery were divided into two groups based on surgical biopsy results: unilateral bacterial sinusitis (UBS, n = 45) and MFB (n = 56). Stratified random sampling of 30 patients from each group was performed to adjust for age. The number of dental implants on maxillary teeth and degree of penetration into the maxillary sinus was radiologically evaluated. The number of patients with dental implants was greater (P = 0.085) and the number of implants was significantly higher (P = 0.031) in the MFB group. Dental implant can be a potential risk factor for MFB development. Therefore, dental implant surgeons should take caution in penetrating the maxillary sinus floor during implant insertion and otolaryngologists should consider the possibility of fungus ball when assessing patients with sinusitis who have dental implants.

Combination of a surgical template and a collagen strip for guiding sinus floor elevation in the oblique sinus floor: A technical note

Sinus floor elevation (SFE) by transcrestal approach has been proven to be a predictable and minimally invasive treatment that augments posterior maxilla with insufficient bone height, allowing the prosthetic rehabilitation of this area with dental implants. However, precise and sufficient elevation of the Schneiderian membrane without perforation is challenging through this blind technique especially in the presence of anatomical restrictions. This note describes a novel technique combining a surgical template and an absorbable collagen sponge (ACS) strip for transcrestal SFE in the oblique sinus floor. A surgical template was used to locate the oblique sinus floor and a collagen strip was placed to orient membrane elevation, meanwhile, protect the sinus membrane. Within the limits of present observation, this technique may increase the manipuility while reducing the risk of complications.

Clinical efficacy of transcrestal sinus floor augmentation, in comparison with lateral approach, in sites with residual bone height ≤6 mm: A systematic review and meta-analysis

OBJECTIVE

This paper addressed two focused questions: Focused question 1 (Q1) "what is the clinical efficacy of transcrestal sinus floor augmentation (TSFA), as compared to lateral sinus floor augmentation (LSFA) in sites with residual bone height (RBH) ≤6 mm, in randomized clinical trials (RCTs) and controlled clinical trials (CCTs)?"; Focused question 2 (Q2) "what is the estimated effectiveness of TSFA for outcomes in Q1, in RCTs, CCTs or cohort studies?"

MATERIALS AND METHODS

An electronic search (PubMed, EMBASE, The Cochrane Central Register of Controlled Trials) and hand search were conducted from January 1986 until December 2022. All eligible clinical studies expressly reporting TSFA in sites with RBH ≤6 mm were included. The data were extracted, and the risk of bias in individual studies was evaluated. Meta-analysis was performed whenever possible.

RESULTS

Seven RCTs were included for Q1 and 25 studies (9 RCTs, 2 CCTs, 14 single arm cohort studies) for Q2. Q1: Meta-analysis did not show significant difference in the implant survival, sinus membrane perforation and marginal bone loss between TSFA and LSFA groups. Q2: Meta-analysis showed TSFA had a high implant survival rate (96.5%, 95% CI: 93.2%-98.9%) at least 1 year after surgery, and limited sinus membrane perforation (5.4%, 95% CI: 2.7%-8.8%). The results also presented higher patient satisfaction for TSFA.

CONCLUSION

With the limitations of the present study (high risk of bias in individual studies), it can be concluded that there was no significant difference in implant survival, Schneiderian membrane perforation and MBL between two approaches in sites with RBH ≤6 mm.

Factors impacting new bone formation in transcrestal sinus floor elevation followed by implant placement: a cross-sectional study

Objectives

This study aimed to evaluate factors related to new bone formation (NBF) following simultaneous implant placement with transcrestal sinus floor elevation (TSFE).

Materials and methods

Between 2008 and 2020, 357 implants (276 patients) were placed with TSFE. Clinical and radiographic examinations were performed at the preoperative, postoperative, restoration, and follow-up stages. Marginal bone loss, during healing, and the survival rate were retrospectively analyzed.

Results

Implant protrusion lengths (IPL: 3–5 mm) significantly influenced NBF during the healing period (P-value = 0.026, Odds Ratio = 1.15, 95% confidence interval = 1.02- 1.30). Bone grafting was correlated with NBF (P-value = 0.001). The distance between the implant and lateral wall of the sinus (mesial: P-value = 0.041, distal: P-value = 0.019, buccal: P-value = 0.032, lingual: P-value = 0.043) and angle between the implant and sinus floor significantly influenced NBF in four directions (mesial: P-value = 0.041, distal: P-value = 0.02, buccal: P-value = 0.047, lingual: P-value = 0.005). Implant shape (cylindrical or conical), perforations, smoking, and diabetes did not significantly affect NBF during the healing period (P > 0.05).

Conclusion

Increasing the distance and angle between the implant and lateral wall of the sinus floor corresponded with reduced NBF. IPL may be an important factor that should be considered.

Clinical relevance

Our study analyzed new bone formation following transcrestal sinus floor elevation among patients who underwent this procedure with simultaneous implant placement, several factors (including angle and distance between sinus and lateral wall and implant protrusion length) were included in our study.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12903-022-02352-6.

Effect of Sinus Perforation with Flaplessly Placed Mini Dental Implants for Oral Rehabilitation: A 5-Year Clinical and Radiological Follow-Up

Background: Flaplessly placed one-piece mini dental implants (MDI) are an option to support maxillary overdentures. Evenly distribution of the implants over the atrophic alveolar process implies a risk of accidental sinus perforation in the posterior area which could induce sinus-related pathology. Methods: Thirty-one patients received 5–6 maxillary MDIs. Schneiderian membrane swelling was assessed with CBCT at the deepest point of the sinus in the mid-sagittal plane prior to surgery (baseline), after 2 and 5 years. Additionally, subjective patient-reported rhinosinusitis complaints, the effect of smoking, and gender differences were investigated. Results: Mean thickness of the Schneiderian membrane was 2.87 mm at baseline, 3.15 mm at 2 years, and 4.30 mm at 5 years in 27 of 31 initially treated patients. MDI perforation was detected in 21/54 sinuses. At 2 years, perforation length does not affect membrane thickness whereas baseline swelling does. In smokers, each perforated mm induced 0.87 mm additional swelling. After 5 years, the effect of baseline swelling becomes smaller whereas perforation length became statistically significant, with 0.53 mm increase for every perforated mm. The effect of smoking lost its significance. No relations between gender, membrane thickness changes, or subjective clinical sinus complaints and MDI perforation were found. Conclusion: Accidental MDI sinus perforation induces Schneiderian membrane swelling but does not interfere with clinical sinusal outcome after 5 years.

Maxillary Sinusitis as a Complication of Zygomatic Implants Placement: A Narrative Review

Aims: The aim of this review is to consider maxillary sinusitis as a complication of zygomatic implants placements. Maxillary sinusitis a common complication but in the literature there are no reviews that focus only on this condition and its possible treatment. This review was carried out with to highlight the main findings of the literature on this topic and to improve knowledge in this field. Methods: The search strategy resulted in 155 papers. After selection of the inclusion criteria only 11 papers were examined. From the papers these, 12.3% patients presented maxillary sinusitis but only four studies evaluated sinusitis (both clinical and radiological evaluation). The most common treatment used by the authors were antibiotics alone or combined with functional endoscopic sinus surgery (FESS). Results: The literature shows an absence of precise and shared guidelines diagnosis and post-operative follow-up, and of the treatment of maxillary sinusitis following zygomatic implantology. It has not been determined if the surgical placement of ZIs is better than the other techniques for treatment of the onset of maxillary sinusitis in the post-operative period. Conclusion: To date there are no shared protocols for maxillary sinusitis treatment. In our experience, and according to the literature in the presence of risk factors such as age, comorbidities, smoking, nasal septal deviation or other anatomical variants, we suggested that FESS is performed at the same time as placement of zygomatic implants.