Augmentation of keratinized tissue using autogenous soft-tissue grafts and collagen-based soft-tissue substitutes at teeth and dental implants: Histological findings in a pilot pre-clinical study.

AIM: To histomorphometrically assess three treatment modalities for gaining keratinized tissue (KT) at teeth and at dental implants. MATERIALS AND METHODS: In five dogs, the distal roots of the mandibular second, third and fourth premolars were extracted. Dental implants were placed at the distal root areas 2 months later. After another 2 months, KT augmentation was performed at both distal (implants) and at mesial root (teeth) areas in the presence (wKT groups) or absence (w/oKT groups) of a KT band at the mucosal/gingival level. Three treatment modalities were applied randomly: apically positioned flap only (APF), free gingival grafts (FGGs) and xenogeneic collagen matrices (XCMs). A combination of the above produced six groups. Two months later, tissue sections were harvested and analysed histomorphometrically. RESULTS: The median KT height and length were greatest at implants with FGG in both wKT (3.7 and 5.1 mm, respectively) and w/oKT groups (3.7 and 4.6 mm), and at teeth with FGG in wKT groups (3.7 and 6.1 mm) and with APF in the w/oKT groups (3.9 and 4.4 mm). The XCM and APF produced more favourable results at teeth than at implants. CONCLUSIONS: FGG was advantageous in gaining KT, especially at implants.

Effects of implant placement timing and type of soft-tissue grafting on histological and histomorphometric outcomes in a preclinical canine model.

AIM: To determine the effects of implant timing and type of soft-tissue grafting on histological and histomorphometric outcomes in a preclinical model. MATERIALS AND METHODS: Four implant placement protocols were randomly applied at the mesial root sites of the third and fourth mandibular premolars in 10 mongrel dogs: immediate placement (group IP), early placement (group EP), delayed placement with/without alveolar ridge preservation (groups ARP and DP, respectively). A connective-tissue graft (CTG) or porcine-derived volume-stable collagen matrix (VCMX) was applied to enhance the ridge profile (simultaneously with implant placement in group IP and staged for others), resulting in five sites for each combination. All dogs were sacrificed 3 months after soft-tissue grafting. Histological and histomorphometric analyses were performed, and the data were analysed descriptively. RESULTS: CTG and VCMX were difficult to differentiate from the augmented area. The median total tissue thickness on the buccal aspect of the implant was largest in group IP/CTG (between 2.78 and 3.87 mm). The soft-tissue thickness was generally favourable with CTG at all implant placement timings. Within the DP groups, CTG yielded statistically significantly larger total and soft-tissue thickness than VCMX (p < .05). Among the groups with VCMX, group EP/VCMX showed the largest soft-tissue thickness at apical levels to the implant shoulder. CONCLUSIONS: CTG generally led to greater tissue thickness than VCMX.

A Novel Approach for the Treatment of Recurrent Oroantral Fistula Occurring at an Infected Sinus Augmentation Site.

Closing a recurrent oroantral fistula (OAF) that occurs at an infected sinus augmentation site is a challenge for clinicians. The recurrent OAF has a detrimental impact on bone regeneration and subsequent implant placement. This case report includes three cases in which sinus graft infection and OAF occurred after maxillary sinus augmentation (MSA). In these cases, treatments to control sinus infection were performed using an otolaryngologist; then, intraoral interventions comprising mucosal flap procedures, bone grafts, and barrier membrane applications were performed 2-5 times by oral surgeons. Nevertheless, OAF recurred persistently. The failure to stop OAF recurrence may be due to the inability to effectively block air pressure at the OAF site. Following a comprehensive debridement of the infected tissue at the previous sinus augmentation site, a pouch was created through sinus mucosal elevation. The perforated sinus mucosa at the OAF site was covered with a non-resorbable membrane in one case and with resorbable collagen membranes in the other two cases, followed by bone grafting within the pouch. Lastly, this procedure was completed by blocking the entrance of the pouch with a cortical bone shell graft and a resorbable collagen membrane. The cortical bone shell graft, obstructing the air pressure from the nasal cavity, facilitated bone formation, and, ultimately, allowed for implant placement. Within the limitations of the present case report, the application of a guided bone regeneration technique involving a cortical bone shell graft and a barrier membrane enabled the closure of the recurrent OAF and subsequent implant placement.

Changes in sinus mucosal thickening in the course of tooth extraction and lateral sinus augmentation with surgical drainage: A cone-beam computed tomographic study.

OBJECTIVES: The objective of the study was to evaluate the radiographic changes in sinus mucosal thickness (SMT) in patients with mucosal thickening of odontogenic origin after maxillary molar extraction and lateral sinus augmentation with simultaneous surgical drainage and implant placement. MATERIALS AND METHODS: Forty-six patients were included in this study. The changes in SMT were evaluated using cone-beam computed tomography images produced at four time points: before extraction (T0), before surgery (T1), immediately after surgery (T2), and after prosthesis delivery (T3), and statistical differences between time points were analyzed. The changes in SMT and augmented bone height (ABH) regarding the reason of extraction, smoking, ostial patency, and the presence of postoperative sinusitis were also evaluated. RESULTS: Over time points, SMT gradually decreased (T0: 19.44 ± 9.22 mm, T1: 15.10 ± 8.89 mm, T2: 8.42 ± 6.01 mm, and T3: 4.16 ± 4.91 mm) (p < .05). Five out of 6 patients with ostial obstruction at T1 presented ostial patency at T3. Two patients developed postoperative sinusitis but recovered with medication. Ostial patency at T1, SMT at T1, and reason of extraction did not statistically significantly influence SMT at T3. SMT at T1 had no statistically significant impact on ABH change between T2 and T3. CONCLUSION: Sinus mucosal thickness was gradually reduced by extraction of compromised teeth and drainage during lateral sinus augmentation. The drainage contributed more to the reduction in SMT.

Keratinized tissue augmentation using collagen-based soft tissue substitute with/without epidermal growth factor on buccally positioned implants: a pilot preclinical study.

OBJECTIVES: To investigate the effect of epithelial growth factor (EGF) with collagen matrix (CM) on the gain of KT for buccally positioned implants in dogs. MATERIALS AND METHODS: In five dogs, four implants were placed buccally with the whole part of KT excision on the buccal side (two implants per each hemi-mandible). After one month, KT augmentation was performed: 1) free gingival grafts (FGG), 2) collagen matrix (CM) only, 3) CM soaked with 1 µg/g of EGF, and 4) CM soaked with 10 µg/g of EGF (n = 5 in each group). The experimental animals were sacrificed three months post-KT augmentation. Clinical, histologic, and histomorphometric analyses were performed. RESULTS: The clinical KT zone was the highest in group FGG (5.16 ± 1.63 mm). Histologically, all groups presented buccal bony dehiscence. Regarding newly formed KT, no specific difference was found among the groups, but robust rete pegs formation in some specimens in group FGG. Histomorphometric KT height (4.66 ± 1.81 mm) and length (5.56 ± 2.25 mm) were the highest in group FGG, whereas similar increases were noted in the rest. The buccal soft tissue thickness at the coronal part of the implant did not exceed 2 mm in all groups. CONCLUSION: All groups presented increased KT zone, but FGG treatment was more favored. The addition of EGF to CM appeared not to enhance KT formation. CLINICAL RELEVANCE: FGG treatment was more favorable to re-establish the KT zone than other treatment modalities.

Management of Posterior Mandibular Bone Cavitation for Dental Implant Placement: A Case Series of 5-24 Years of Follow-Up.

Focal osteo-cavitation in the posterior mandible is a condition that clinicians do not know well. Inadvertent implant placement in such areas may result in nerve damage due to abrupt drill penetration and implant displacement in the medullary space. In the present case series, focal osteo-cavitation was managed with the following procedures: (1) undersized drilling, (2) gentle trabecular curettage, (3) bone substitute material grafting in the cavity, and (4) long healing period for osseointegration. In all cases, a sudden loss of drilling pressure immediately after passing through the thin cortical layer revealed focal osteo-cavitation. Following undersized drilling and gentle trabecular curettage, the bone substitute material was packed into the cavity with care not to press the inferior alveolar canal. Implant placement was subsequently performed. Despite a lack of primary implant stability in 3 of 4 cases, all implants were successfully osseointegrated after 6-9 months. Over 5-24 years, all implants functioned well.

Successful Management of Late Sinus Graft Infection via Functional Endoscopic Sinus Surgery and Press-Fit Block Bone Graft: A Case Report.

The purpose of this case report is to feature an interesting case where a staged approach was used to manage a failed implant site that led to a late sinus graft infection and sinusitis with an oroantral fistula (OAF), by using functional endoscopic sinus surgery (FESS) and an intraoral press-fit block bone graft technique. Sixteen years ago, a 60-year-old female patient underwent maxillary sinus augmentation (MSA) with 3 implants placed simultaneously in the right atrophic ridge. However, No. 3 and 4 implants were removed due to advanced peri-implantitis. The patient later developed purulent discharge from the site, headache, and complained of air leakage due to an OAF. The patient was referred to an otolaryngologist for FESS to treat the sinusitis. Two months after FESS, the sinus was re-entered. Residual inflammatory tissues and necrotic graft particles in the OAF site were removed. A block bone harvested from the maxillary tuberosity was press-fitted to the OAF site and grafted. After 4 months of grafting, the grafted bone was well incorporated with the surrounding native bone. Two implants were successfully placed in the grafted site with good initial stability. The prosthesis was delivered 6 months after implant placement. After the 2 years of follow-up, patient was functioning well without sinus complications. Within limitation of this case report, the staged approach via FESS and intraoral press-fit block bone graft is an effective method that can be used to successfully manage OAF and vertical defects at the implant site.

Lateral Peri-Implantitis: Successful Management via Guided Bone Regeneration at Mandibular First Molar Implant.

Infections occurring around implants are divided into marginal peri-implantitis and retrograde peri-implantitis (RPI). Marginal peri-implantitis starts in the crestal bone and progresses to the apical portion, and RPI starts in the apical bone and progresses to the coronal portion. However, lateral peri-implantitis (LPI) occurring on the side of the implant body has not yet been reported, and the cause is unclear. This 63-year-old male patient is a case of unusual bone resorption that occurred in the lateral portion of the implant body 26 months after lateral bone augmentation. The origin of LPI was an infection at the site of laterally augmented bone. Rather than implant removal, this report demonstrates an alternative treatment option of guided bone regeneration after the enucleation and detoxification of the implant surface with successful clinical and radiographic results for 2 years.

Submerged Technique of Partially De-Epithelialized Free Gingival Grafts for Gingival Phenotype Modification in the Maxillary Anterior Region: A Case Report of a 34-Year Follow-up.

A coronally advanced flap combined with a subepithelial connective tissue graft is considered the gold standard for achieving root coverage on exposed root surfaces. Nevertheless, challenges arise when this technique is applied to multiple teeth and when the palatal soft tissue is very thin. Several surgical modifications have been reported to simultaneously achieve both single or multiple root coverage and widening of the keratinized gingiva. In this context, there have been no reported cases utilizing the submerged technique with partially de-epithelialized free gingival grafts. We intend to introduce a submerged technique involving partially de-epithelialized free gingival grafts for the modification of soft tissue phenotypes in the maxillary anterior region.

Bone Regenerative Potential of Cross-Linked Collagen Membrane in Peri-Implant Osseous Defect: Case Series with Histologic/Micro-Computed Tomographic Findings.

The role of a barrier membrane is crucial in guided bone regeneration (GBR) for space creation and cell occlusiveness. Those properties of the membrane should be sustained for a sufficient period. For such purpose, several cross-linked collagen membranes were introduced and demonstrated favorable clinical outcomes. However, histologic data were not sufficient to support the effect of cross-linked collagen membranes. In the present case series, healing after GBR using a cross-linked collagen membrane was investigated in-depth via histologic and micro-computed tomographic (micro-CT) analyses. 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide cross-linked collagen membrane was used in GBR for treating various peri-implant bone defects in seven patients. After 4-7 months of healing, newly formed tissue of hard consistency was observed over the implant platform. This tissue was carefully harvested and assessed. In micro-CT and histological analyses, evident new bone formation was revealed, especially in the vicinity of the collagen membrane. Moreover, it was histologically found that some newly formed bone was in intimate contact with the membrane. Although the exact mechanism of bone regeneration in the present cases was not clearly elucidated, the cross-linked collagen membrane appeared to contribute to ossification in GBR. Further studies are needed to confirm the findings of the present case series.

Dimensional ridge changes in conjunction with four implant timing protocols and two types of soft tissue grafts: A pilot pre-clinical study.

AIM: To determine the effect of (1) implant placement timing and (2) the type of soft tissue graft in terms of ridge profile changes. MATERIALS AND METHODS: Four implant treatment modalities were applied in the mesial root areas of the third and fourth mandibular premolars of 10 mongrel dogs alongside connective-tissue graft (CTG) and volume-stable cross-linked collagen matrix (VCMX): immediate, early, and delayed placement (DP), and DP following alveolar ridge preservation (ARP). All dogs were sacrificed 3 months after soft tissue augmentation. Standard Tessellation Language files from designated time points were analysed. RESULTS: Compared with the pre-extraction situation, the median width of the ridge demontstrated a linear increase only in group ARP/CTG (0.07 mm at the 2-mm level), whereas all other groups showed a reduction (between -1.87 and -0.09 mm, p > .05). Groups ARP/CTG (0.17 mm) and DP/CTG (0.05 mm) exhibited a profilometric tissue gain in a set region of interest (p > .05). The net effect of CTG and VCMX ranged from 0.14 to 0.79 mm. CONCLUSIONS: Dimensional ridge changes varied between treatment protocols. ARP with CTG led to the smallest difference in ridge profile between the pre-extraction and the study end time point. Both CTG and VCMX enhanced the ridge contour.

Effectiveness of hydraulic pressure-assisted sinus augmentation in a rabbit sinus model: a preclinical study.

OBJECTIVES: To investigate the effectiveness of hydraulic pressure-assisted sinus augmentation (SA) in a rabbit sinus model in terms of radiographical and histological healing. MATERIALS AND METHODS: Bilateral SA was performed in 12 rabbits. Each sinus was randomly assigned to either a hydraulic pressure-assisted SA (test) or a conventional SA (control) group. Healing periods of 2 and 4 weeks were applied (n = 6 for each week). Healing pattern including newly formed bone (NB) and residual bone substitute material (RM) was analyzed with microcomputed tomographically, histologically, and histomorphometrically. RESULTS: No sinus membrane perforation was detected in either group. In the microcomputed tomographic analysis, the test group exhibited higher apico-coronal spread of RM compared to the control group (p < 0.05). Particularly, the test group exhibited several masses of NB out of the cluster of RM. Histologically, the test group showed an elongated shape of the augmented space, whereas the control group generally presented a dome shape. Histomorphometrically, the total augmented area and the area of NB (1.32 ± 0.56 vs. 0.84 ± 0.40 mm2 at 2 weeks, 2.24 ± 1.09 vs. 2.22 ± 0.85 mm2 at 4 weeks) were not significantly different between the test and the control groups at both healing periods (p > 0.05). CONCLUSION: Hydraulic pressure-assisted SA led to new bone formation in the distant areas from the bony access hole, but similar histological healing pattern to conventional SA. CLINICAL RELEVANCE: Hydraulic pressure-assisted SA is a promising option for treating pneumatized posterior maxilla.

Infra- and labio-position of two maxillary central incisor implants in an older adult at a 17-year follow-up.

OBJECTIVE: This report aims to present an infra- and labio-version of the implants relative to the surrounding teeth in an older patient. BACKGROUND: Infra-positioning of dental implants has been sometimes observed in young adults but not in older patients. MATERIALS AND METHODS: Two implants were placed in both central incisor areas in a 63-year-old female patient in 2002. A splinted implant prosthesis was inserted six months later. RESULTS: After 17 years, a deviation in the position of the implant crown on the #21 area was 9.94 mm labially and 4.69 mm apically with respect to the adjacent tooth (#22). The corresponding values of the implant crown on the #11 area were 5.96 and 2.34 mm (with respect to #12), respectively. CONCLUSION: Dental implants in older adults might develop horizontal and vertical discrepancies relative to the neighbouring teeth.

Endodontic sealer-induced maxillary sinusitis: intraoral surgical approach and implant placement at a site of failed nasal endoscopic surgeries.

A 28-year-old male patient was referred from an otorhinolaryngologist for managing unilateral chronic maxillary sinusitis (MS). The patient had undergone two functional endoscopic sinus surgeries (FESS), although the MS was not resolved. Based on his dental history, endodontic treatment had been done on the symptomatic area. A leak of endodontic sealer and peri-apical lesion on tooth #14 was found on cone-beam computed tomographic examination. Extraction of tooth #14 and the modified Caldwell-Luc operation were performed to remove the endodontic sealer material and relevant inflammatory tissue. The sinus membrane lining was maintained as much as possible during the surgery. Implant placement was performed on the tooth extraction site. All clinical symptoms disappeared after the surgery. Radiographic and endoscopic examination revealed successful osseointegration of the implant and complete resolution of the MS. FESS alone may not be sufficient to treat MS derived from dental origin. For unilateral MS, dental history should be carefully checked.

Effectiveness of xenogeneic and synthetic bone-block substitute materials with/without recombinant human bone morphogenetic protein-2: A preclinical study using a rabbit calvarium model.

AIM: To investigate new bone (NB) formation by using bone-block substitute materials with/without recombinant human bone morphogenetic protein-2 (rhBMP-2). MATERIALS AND METHODS: Three synthetic bone-block substitute materials [biphasic calcium phosphate (BCP); nanostructured hydroxyapatite (NH); 3D-printed tricalcium phosphate/hydroxyapatite (3DP)] and one xenogeneic deproteinized bovine bone mineral (DBBM) block substitute were affixed to rabbit calvarium using osteosynthesis screws, either with rhBMP-2 (n = 12) or without rhBMP-2 (n = 16). At 2 or 12 weeks (n = 6 with rhBMP-2 and n = 8 without rhBMP-2 for each week), histologic, histomorphometric and microcomputed tomography analyses were performed. RESULTS: The application of rhBMP-2 increased NB formation in all experimental groups at both weeks. DBBM resulted in a greater area of NB compared with synthetic blocks either with or without rhBMP-2 at 2 weeks (2.8 ± 0.9 vs. 1.4 ± 0.5-1.9 ± 1.4 mm2 ; 1.4 ± 1.0 vs. 0.6 ± 0.3-0.9 ± 0.5 mm2 ) and without rhBMP-2 at 12 weeks (3.0 ± 0.8 vs. 1.7 ± 0.7-2.6 ± 1.5 mm2 ) (p > 0.05). NB formation did not differ significantly for DBBM and the three types of synthetic block with rhBMP-2 at 12 weeks (4.5 ± 2.0 vs. 3.8 ± 0.7-5.1 ± 1.1 mm2 ; p > 0.05). CONCLUSIONS: rhBMP-2 enhanced NB in all blocks. DBBM blocks yielded more NB than synthetic blocks without rhBMP-2. The application of rhBMP-2 appears to compensate for differences in late healing.

Complication and Salvage of Sinus Floor Elevation in the Maxillary Sinus With Asymptomatic and Noncalcified Fungus Colonization: A Case Report.

The present study aimed to report (1) the sequela of sinus floor elevation (SFE) in the posterior maxilla with severe sinus membrane thickening and an undiagnosed fungal colonization but a patent ostium and (2) a treatment course without implant removal. A 73-year-old woman underwent dental implant placement in the left posterior maxillary area. Although the patient was asymptomatic, severe sinus membrane thickening with Haller cells was observed on a radiographic examination, but the ostium was patent. After SFE and simultaneous implant placement, the patient developed acute sinusitis and was referred to an otolaryngologist. Functional endoscopic sinus surgery (FESS) was performed, resulting in resolution of the infection and salvage of the augmentation and the implant. The histopathologic examination revealed the fungal ball that could not be diagnosed on preoperative dental radiography. During the 2 years after the delivery of the final prosthesis, a significant reduction in membrane thickness was observed. The implants were functioning well. Clinicians should recognize fungal colonization as an etiology of sinus membrane thickening and provide proper pre- and postoperative management, including FESS.

Late implant placement following ridge preservation versus early implant placement: A pilot randomized clinical trial for periodontally compromised non-molar extraction sites.

AIM: To compare late implant placement following alveolar ridge preservation (LP/ARP) and early implantation (EP) in periodontally compromised non-molar extraction sites with respect to soft tissue levels, aesthetics, and patient-reported outcomes. MATERIALS AND METHODS: Sixteen patients were randomly allocated to groups LP/ARP (n = 9) or EP (n = 7). Group LP/ARP received ARP using deproteinized bovine bone mineral containing 10% collagen and a native bilayer collagen membrane, and group EP received only extraction. Implant placement was performed 4-8 weeks post-extraction in group EP and 4 months post-alveolar ridge preservation in group LP/ARP. The soft tissue levels, pink/white esthetic scores, and periodontal parameters were evaluated at 1 year post-loading. Patient's discomfort level was evaluated in terms of extraction/ARP and implant placement. RESULTS: No implant failure or biologic complications occurred. There was no statistically significant difference in the median change of the midfacial mucosal margin (0.03 for group LP/ARP, -0.19 mm for group EP) and the mesial/distal papilla (0.62/0.25 mm for group LP/ARP, 0.29/-0.5 mm for group EP), pink/white esthetic scores, periodontal parameters, and patient's discomfort between the two groups. CONCLUSION: Both implant placement protocols led to comparable outcomes in soft tissue levels, periodontal parameters, and patient's discomfort level.

Augmentation of keratinized tissue at tooth and implant sites by using autogenous grafts and collagen-based soft-tissue substitutes.

AIM: To investigate the effect of three treatment modalities on the gain of keratinized tissue (KT) at tooth and implant sites in dogs. MATERIALS AND METHODS: In five dogs, the distal roots of the mandibular second, third and fourth premolars were extracted, while the mesial roots were maintained. After 2 months of healing, implants were placed with KT excision. After another 2 months of healing, free gingival grafts, collagen-based matrices and apically positioned flap only were applied. The height of KT was measured during implant placement, immediately before soft-tissue grafting and after 10, 30 and 60 days. RESULTS: Two months after KT excision, spontaneous KT regrowth was greater at tooth sites than at implant sites (median, 2.0 mm vs. 1.1 mm). The outcomes of soft-tissue grafting at implant sites favoured the free gingival graft treatment, with a greater final median height (5.0-5.5 mm) and increase in KT (4.0-4.2 mm). Locations of the recipient sites significantly influenced KT regeneration at both tooth and implant sites. CONCLUSIONS: At implant sites, the free gingival graft treatment led to higher KT regeneration. At tooth sites, however, the differences between the three treatment modalities seemed clinically irrelevant.

Explorative randomized controlled study comparing soft tissue thickness, contour changes, and soft tissue handling of two ridge preservation techniques and spontaneous healing two months after tooth extraction.

OBJECTIVES: To compare two ridge preservation techniques and spontaneous healing in terms of soft tissue thickness, contour changes, and soft tissue handling two months after tooth extraction. METHODS: Thirty-six patients were included with buccal bone plate dehiscences of up to 50% after single-tooth extraction in the esthetic zone. They were randomly assigned to receive one of three procedures: a deproteinized bovine bone mineral with 10% collagen (DBBM-C) covered with a collagen matrix (DBBM-C/CM), DBBM-C alone, or spontaneous healing (SH). Two months later, the status of soft tissue healing was assessed, and the thickness of the mucosa was measured at the center of the site. Thereafter, implants were placed and the need for further guided bone regeneration (GBR) to cover exposed implant surfaces was assessed. RESULTS: Thirty-six patients were evaluated at the day of implant placement. An invagination of the soft tissues was recorded in 41.7% (n = 12), 53.8% (n = 13), and 90.9% (n = 11) of the sites in groups DBBM-C/CM, DBBM-C, and SH, respectively. The median thickness of the mucosa measured was 3.0 mm in group DBBM-C/CM, 2.1 mm in group DBBM-C, and 1.5 mm in group SH. Additional GBR was necessary in 66.7% (n = 12), 53.8% (n = 13), and 90.9% (n = 11) of the sites in groups DBBM-C/CM, DBBM-C, and SH, respectively. CONCLUSIONS: The present explorative study revealed slight tendencies for more favorable soft tissue conditions with less invaginations as well as increased soft tissue volume and thickness in groups having received an alveolar ridge preservation procedure compared to spontaneously healed sites at 8 weeks of healing.

Functional Endoscopic Sinus Surgery for Paranasal Sinusitis Originating From a Peri-implantitis-Triggered Infection in the Augmented Maxilla: A Case Report.

The aim of this case report was to report the course of treatment for advanced paranasal sinus infection triggered by peri-implantitis, managed using functional endoscopic sinus surgery (FESS), with outcomes. A nonsmoking male patient received sinus augmentation with implant placement on his left posterior maxilla 15 years ago. Possibly due to noncompliance to maintenance, peri-implantitis developed and progressed into the augmented bone area in the maxilla. Eventually, maxillary sinusitis occurred concomitantly with a spread of the infection to the other paranasal sinuses. Implant removal and intraoral debridement of inflammatory tissue were performed, but there was no resolution. Subsequently, FESS was performed, with removal of nasal polyp and sequestrum. After FESS, the patient's sinusitis resolved. Histologically, the sequestrum was composed of bone substitute particles, necrotic bone, stromal fibrosis, and a very limited cellular component. Two implants were placed on the present site, and no adverse event occurred for up to 1 year after the insertion of the final prosthesis. Peri-implantitis in the posterior maxilla can trigger maxillary sinusitis with concomitant infection to the neighboring paranasal sinuses. FESS should be considered to treat this condition.