Time management in multistep periodontal and implant treatments: a practical guide

In addition to the proper selection of techniques, appropriate treatment sequencing and prioritization are prerequisites for successful periodontal and implant procedures. The aim of this study was to provide evidence-based time frames for various procedures pertaining to periodontal and implant treatment. A literature review was conducted to collect data on tissue healing; in areas in which data were lacking, the viewpoints of experienced clinicians were solicited to establish a consensus. This review reports recommended time frames for the healing processes associated with surgical crown-lengthening procedures (both functional and esthetic), fresh socket management, alveolar ridge management, soft tissue management, sinus floor augmentation, implant loading, and peri-implant defect management.

Randomized controlled multi-centre study comparing shorter dental implants (6 mm) to longer dental implants (11-15 mm) in combination with sinus floor elevation procedures: 10-year data

AIM

To compare implant survival and complication rates between shorter and standard-length implants with sinus augmentation and restored with single crowns, at 10 years of loading.

MATERIALS AND METHODS

One-hundred and one patients (137 implants) with a ridge height of 5-7 mm in the posterior maxilla were randomly assigned to two treatment modalities: shorter implants (6 mm) (group short [GS]) or standard-length implants (11-15 mm) with sinus grafting (group graft [GG]). Following the insertion of final restorations, patients were regularly recalled for up to 10 years. Assessed outcomes encompassed implant survival, marginal bone levels (MBLs), biological and technical parameters and patient-reported outcome measures (OHIP-49 = Oral Health Impact Profile). Non-parametric statistical analysis was used to analyse the data.

RESULTS

For the 5- to 10-year follow-up period, 77 patients with 105 implants (GS: 36 patients/48 implants; GG: 41/57) were available for re-examination (drop-out rate 21%). Implant survival rates at the patient level were 96.0% (GS; 2 failures) and 100% (GG) (inter-group p = .24). Median MBLs amounted to 0.00 mm (min 0.00; max 3.25; GS) and 0.00 mm (min 0.00; max 4.55; GG) (inter-group p = .73). Technical complications predominantly occurred within the first 5 years (inter-group p > .05). Peri-implantitis rates were 4.2% (GS) and 13.3% (GG) (intergroup p = .37). Median OHIP-49 scores were 7.00 (0.00; 39.00; GS) and 9.00 (0.00; 196; GG) (inter-group p = .61) at 10 years.

CONCLUSIONS

Based on similar 10-year implant survival rates, reduced patient morbidity and lower costs, the use of shorter dental implants might well serve as an alternative treatment concept to longer implants placed in conjunction with sinus grafting for patients with a limited ridge height in the posterior maxilla. Study register: https://clinicaltrials.gov/ct2/show/NCT01030523.

Dynamically guided transantral piezoelectric endodontic microsurgery: A case report with technical considerations

AIM

Endodontic microsurgery (EMS) of maxillary molars may represent a complex challenge to the clinician due to the location of the roots and the proximity of the maxillary sinus floor. This report aimed to describe the simultaneous use of a computer-assisted dynamic navigation (C-ADN) system and piezoelectric bony-window osteotomy for the transantral microsurgical approach of a maxillary left first molar with adequate root canal filling and symptomatic apical periodontitis.

SUMMARY

This case report highlights the importance of C-ADN to carry out a minimally invasive buccal surgical access to palatal roots affected by apical periodontitis and provides a practical example to help clinicians make treatment decisions based on the available evidence. Clinical and tomographic evaluations were performed before the surgical procedure and at 24-month follow-up. This case was treated using a C-ADN system fitted to a piezotome for the buccal approach of the buccal roots, maxillary sinus membrane lifting, and for transantral location, root-end resection, cavity preparation, and filling of the palatal root. The navigation system allowed to achieve an accurate apical canal terminus location and root-end filling of the three roots with a minimally invasive piezoelectric crypt approach. At the 24-month follow-up examination, the patient remains asymptomatic, with normal periapical structures, and regeneration of maxillary sinus walls. It was concluded that the combination of dynamic navigation with piezoelectric bony-window osteotomy offers enhanced accuracy, tissue preservation, diminished risk of iatrogenic complications, and could maximize success and survival rates in transantral EMS.

Deep learning for the identification of ridge deficiency around dental implants

OBJECTIVES

This study aimed to use a deep learning (DL) approach for the automatic identification of the ridge deficiency around dental implants based on an image slice from cone-beam computerized tomography (CBCT).

MATERIALS AND METHODS

Single slices crossing the central long-axis of 630 mandibular and 845 maxillary virtually placed implants (4-5 mm diameter, 10 mm length) in 412 patients were used. The ridges were classified based on the intraoral bone-implant support and sinus floor location. The slices were either preprocessed by alveolar ridge homogenizing prior to DL (preprocessed) or left unpreprocessed. A convolutional neural network with ResNet-50 architecture was employed for DL.

RESULTS

The model achieved an accuracy of >98.5% on the unpreprocessed image slices and was found to be superior to the accuracy observed on the preprocessed slices. On the mandible, model accuracy was 98.91 ± 1.45%, and F1 score, a measure of a model's accuracy in binary classification tasks, was lowest (97.30%) on the ridge with a combined horizontal-vertical defect. On the maxilla, model accuracy was 98.82 ± 1.11%, and the ridge presenting an implant collar-sinus floor distance of 5-10 mm with a dehiscence defect had the lowest F1 score (95.86%). To achieve >90% model accuracy, ≥441 mandibular slices or ≥592 maxillary slices were required.

CONCLUSIONS

The ridge deficiency around dental implants can be identified using DL from CBCT image slices without the need for preprocessed homogenization. The model will be further strengthened by implementing more clinical expertise in dental implant treatment planning and incorporating multiple slices to classify 3-dimensional implant-ridge relationships.

Radiographic assessment of maxillary sinus membrane and lateral wall thickness using cone-beam CT in different facial types in southwestern Saudi Arabia

The anatomy of the edentulous posterior maxilla and maxillary sinus possess unique challenges in implant dentistry. The purpose of this study was to assess maxillary sinus membrane thickness (MT) and lateral wall thickness (LWT) in different facial index profiles and to describe the clinical implications. A retrospective image analysis of 75 CBCT scans was done, which yielded a total of 150 sinus images. The facial index was calculated as per the formula given in the text and grouped as euryprosopic, mesoprosopic and leptoprosopic. The images obtained were of 36 women (48%) and 39 men (52%), with maximum subjects in 30-39 years age group. MT and LWT were measured at three different points on the radiograph at every 3mm from the base of the sinus floor in premolar and molar regions of each image. Results showed females had significant differences from males in LWT in both premolar and molar regions (p = 0.018 and 0.032 respectively). Subjects in 40-49 years of age had significant differences (p = 0.021) in MT in premolar region only. Also, difference in MT in premolar and molar regions were also statistically significant. Lastly, the present study did not find any statistically significant difference in MT and LWT in all three facial indices groups. It can be concluded that different facial indices have no positive correlation with maxillary sinus membrane thickness and lateral wall thickness. Hence, surgical complications are avoidable with proper detailed knowledge and appropriate identification of the anatomic structures characteristic to the maxillary sinus.

Effect of Sinus Membrane Thickness on Membrane Perforation and Bone Augmentation in Transcrestal Sinus Floor Elevation: A Retrospective Study

Sinus membrane thickening is a common maxillary sinus disease. However, a consensus has not been reached on the effect of sinus membrane thickness on the transcrestal sinus floor elevation. This retrospective study evaluated the perforation and bone formation at transcrestal sinus floor elevation sites with different sinus membrane thicknesses. A total of 117 sites in 87 patients treated with transcrestal sinus floor elevation were included in this study. The surgical sites were divided into four groups according to the baseline sinus membrane thickness: Group A (0 to 1 mm), Group B (1 to 2 mm), Group C (2 to 4 mm), and Group D (> 4 mm). CBCT scans were taken before surgery, immediately after surgery, and 6 months after surgery. The mean baseline sinus membrane thickness was 2.16 ± 2.54 mm, and the mean residual alveolar bone height was 6.58 ± 1.85 mm. The mean endosinus new bone height was 3.76 ± 1.95 mm. The perforation rate and endosinus new bone height showed no significant difference among the groups (P > .05). The incidence rates of membrane thickening and perforation were significantly higher in smoking patients (P < .05). Membrane thickening without ostium obstruction may have little impact on transcrestal sinus floor elevation surgery in regards to perforation rate and bone formation. In addition, smoking may be a risk factor for membrane thickening, and the sinus membrane is more likely to perforate during transcrestal surgery when the patient has a history of smoking.

Variables Influencing Bone Formation After Transcrestal Sinus Floor Elevation: Radiographic and Tomographic Evaluations

PURPOSE

To evaluate the influence of initial implant protrusion within the subantral space on hard tissue gain for implants placed simultaneously with transcrestal sinus floor elevation (TSFE) with a biomaterial.

MATERIALS AND METHODS

A total of 50 implants were placed after TSFE in 44 patients using either a human demineralized bone matrix or a deproteinized bone mineral matrix. Intraoral radiographs were obtained before and immediately after surgery. CBCT scans were obtained at the last follow-up (mean: 6.6 years).

RESULTS

The initial bone crest height was 4.6 ± 1.4 mm, and the initial protrusion of the implants above the sinus floor was 3.5 ± 1.4 mm. At the follow-up assessments, the hard tissue mean gain was 2.5 ± 1.5 mm, resulting in a mean residual protrusion of 1.1 ± 1.3 mm. Only 10 implants did not protrude above the apical level of hard tissue. Positive correlations were found between hard tissue gain and initial protrusion (r = 0.55; 95% CI: 0.32 to 0.72; P = .0001), between the initial and final protrusions (r = 0.38; 95% CI: 0.10 to 0.60; P = .007), and between the follow-up period and final protrusion (r = 0.35; 95% CI: 0.07 to 0.58; P = .012).

CONCLUSIONS

The higher the initial protrusion was, the higher were the hard tissue gain and the final protrusion of the implant above the apical level of the hard tissue.

Quantitative analysis of change in bone volume 5 years after sinus floor elevation using plate-shaped bone substitutes: a prospective observational study

PURPOSE

Tricalcium phosphate (TCP) has osteoconductive ability and reportedly offers similar clinical results as autogenous bone grafts in dental implant treatment. However, few reports quantify temporal changes in augmented bone volume after sinus augmentation. We aimed to establish a three-dimensional (3D) quantification method to assess bone volume after sinus augmentation and to evaluate biocompatibility of the TCP plate.

METHODS

Maxillary sinus floor augmentation was performed employing the lateral window technique, and plate-shaped β-TCP (TCP plate) was used instead of granular bone grafting materials. After lifting the sinus membrane, the TCP plate was inserted and supported by dental implants or micro-screws. The changes in bone volumes in the maxillary sinus before and after surgery were recorded using cone-beam computed tomography, saved as Digital Imaging and Communications in Medicine-formatted files, and transformed to Standard Triangle Language (STL)-formatted files. Pre- and post-operative STL data of bone volume were superimposed, and the augmented bone volume was calculated. Moreover, changes in bone volumes, TCP plate resorption rates, and bone heights surrounding the implants were three dimensionally quantified.

RESULTS

Fifteen implants in nine subjects were included in this study. TCP plates secured long-term space making, with results similar to those of granular bone substitutes. Newly formed bone was identified around the implant without bone graft material. TCP plate was absorbed and gradually disappeared.

CONCLUSIONS

A novel 3D quantification method was established to evaluate changes in bone volume. Clinical application of TCP plate in sinus augmentation could be a better procedure in terms of prognosis and safety.

Volume change after maxillary sinus floor elevation with apatite carbonate and octacalcium phosphate

PURPOSE

Maxillary molars have low alveolar bone height diameter due to the presence of the maxillary sinus; thus, a sinus lift may be required in some cases. Changes in the volume of bone substitutes can affect the success of implant therapy. Therefore, this study aimed to compare the changes in the volume of two different bone substitutes-one based on carbonate apatite and the other on octacalcium phosphate-used in maxillary sinus floor elevation.

METHODS

Nineteen patients and 20 sites requiring maxillary sinus floor elevation were included in the study. Digital Imaging and Communications in Medicine data for each patient obtained preoperatively and immediately and 6 months postoperatively were used to measure the volume of the bone grafting material using a three-dimensional image analysis software. The immediate postoperative volume of octacalcium phosphate was 95.3775 mm3 per piece of grafting material used. It was multiplied by the number of pieces used and converted to mL to determine the immediate postoperative volume.

RESULTS

The mean resorption values of carbonate apatite and octacalcium phosphate were 12.7 ± 3.6% and 17.3 ± 3.9%, respectively. A significant difference in the amount of resorption of the two bone replacement materials was observed (P = 0.04).

CONCLUSIONS

The results of this study indicate that both bone substitute materials tend to resorb. The two bone grafting materials that are currently medically approved in Japan have not been in the market for a long time, and their long-term prognosis has not yet been reported. Further clinical data are warranted.

[Review of clinical effects of disk-up sinus reamer(DSR)-based internal sinus floor elevation with implantation in 10 years]

PURPOSE

To analyze the bone remodeling around the implant 10 years after disk-up sinus reamer(DSR)-based internal sinus floor elevation with implantation and to investigate the influence of different factors on implant retention.

METHODS

The clinical and imaging data of patients undergoing DSR-based sinus floor elevation with simultaneous implantation were collected from the Department of Dental Implantology, Affiliated Hospital of Qingdao University from January 2008 to December 2011. Panoramic film and CBCT were used to measure the changes of bone mass around implant in different periods. Kaplan-Meier and Log-rank tests were used to analyze the effects of different factors on implant retention with SPSS 26.0 software package.

RESULTS

The study included 98 patients with a total of 128 implants. During the follow-up of 0-168 months, 7 implants failed, and the remaining formed good osseointegration and functioned, with a 10-year cumulative retention rate of 94.53%. The height of bone formation was (0.29±0.15) mm at the top and (2.74±0.66) mm in the sinus of 75 implant sites with complete imaging data obtained ten years after surgery. Kaplan-Meier and Log-rank tests showed that 8 factors including initial bone height, elevated bone height, mucosal perforation, implant length, implant torsion, diabetes, smoking and periodontitis had significant effects on implant retention.

CONCLUSIONS

The DSR-based internal sinus floor elevation with implantation is a reliable and stable bone augmentation operation for vertical bone defect in maxillary posterior region, with a 10-year cumulative retention rate of no less than 94%. Initial bone height, elevated bone height, mucosal perforation, implant length, implant torsion, diabetes, smoking and periodontitis are the important factors affecting the long-term retention rate of implants.

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.

Utilizing a Novel AI Tool to Detect the Posterior Superior Alveolar Artery's Location's Impact on Maxillary Sinus Mucosal Thickening in the Presence of Periapical Lesions

Periapical lesions have been implicated in sinus-related complications, but the precise influence of anatomical variations in the posterior superior alveolar artery (PSAA) on mucosal thickening remains an uncharted aspect. The new AI tool employed in this research utilizes advanced image processing algorithms to enhance image visualization. Background and Objectives: This study examines the accuracy of a new cone beam computed tomography (CBCT) software (eVol DXS, version 1.0.1.0) employing AI to detect the PSAA's location and the effect of that on maxillary sinus thickening in the presence of periapical lesions. Materials and Methods: This retrospective study included 120 CBCT cases with posterior maxillary periapical lesions and 120 without odontogenic infections. Teeth with proximity (<2 mm) to the sinus were excluded in both groups to eliminate the sinus floor's perforation effect. Both the PSAA locations and maxillary sinus thickening were classified and compared. Results: The mucosal thickening differs significantly (p < 0.001) between the study group and the control group. The study showed that an increased sinus thickness occurred when the PSAA was beneath the sinus membrane in the study group (62.5% compared to 8.6%; p < 0.001 *). The AI tool helped to achieve a 100% identification rate in determining the PSAA locations. Conclusions: AI algorithms for PSAA localization, which affects mucosal thickness in response to periapical lesions, yield excellent results.

Characteristics of CBCT versus panoramic signs of the surrounding bone of molar root protrusions into the maxillary sinus

The study aimed to (a) investigate the amount and characteristics of the surrounding bone of protruded molar roots into the maxillary sinus using cone-beam computed tomography (CBCT) and (b) assess the correlation between the amount of bone with panoramic high-risk signs. Radiographs of 408 roots protruding beyond the sinus floor were evaluated. Axial CBCT images were used to investigate then classify eight characteristics of surrounding bone: no bone; bone < half the root girth in the proximal or buccal-palatal aspect; bone covering half the root girth in the proximal or buccal-palatal aspect; bone > half the root girth in the proximal or buccal-palatal aspect; and, complete bone. These were then grouped into four degrees of bone support: no bone; bone ≤ half the root girth; bone > half the root girth; and, complete bone. Panoramic signs were subclassified as: projection of root; interruption of the sinus floor; darkening of the root; upward curving of the sinus floor; absence of periodontal ligament space; and, absence of the lamina dura. Correlation between the degree of bone and the panoramic signs was evaluated using the Chi-square or Fisher's exact tests. Positive and negative predictive values, sensitivity, specificity, accuracy, and receiver operating characteristic analysis were calculated. Complete bone support was the most common. 'Projection of root' had a high negative predictive value and sensitivity. 'Absence of the periodontal ligament space and lamina dura' had a high positive predictive value, specificity, accuracy, and area under the curve. These two signs were significantly correlated with the degree of bone support.

Single crowns in the posterior maxilla supported by either 11-mm long implants with sinus floor augmentation or by 6-mm long implants: A 10-year randomized controlled trial

OBJECTIVES

To compare the clinical performance of single crowns in the posterior maxilla supported by either 11-mm long implants combined with maxillary sinus floor augmentation (MSFA) surgery or by 6-mm long implants during a 10-year follow-up period.

MATERIALS AND METHODS

Subjects were randomly allocated to receive one 11-mm long implant in combination MFSA or to receive one 6-mm long implant without any grafting. Twenty-one implants in 20 patients were placed in the 6-mm group and 20 implants in 18 patients were placed in the 11-mm group. Both groups were followed by clinical and radiographic examinations up to 10 years. Patients' satisfaction was also scored before treatment.

RESULTS

Two patients died and eight patients moved during the follow-up. Two patients lost an implant in the 6-mm group and one implant was lost in the 11-mm group (implant survival 89.5% and 90.9%, respectively). From loading to 10 years' follow-up, mean ± SE marginal bone loss in the 6-mm group and 11-mm group was 0.18 ± 0.10 mm and 0.26 ± 0.12 mm, respectively, without a significant difference between the groups at 10 years (p = .650). In both groups, indices scores for plaque, calculus, gingiva and bleeding were low as well as mean pocket probing depth. Patients' satisfaction at 10 years was high in both groups; mean overall satisfaction in the 6-mm group and 11-mm group was 9.6 ± 0.6 and 9.2 ± 0.8, respectively (p = .168).

CONCLUSIONS

Placement of 6-mm implants or 11-mm implants combined MFSA are equally successful during a 10-year follow-up period when applied for supporting a single restoration.

Nasoseptal Flap to Repair Large Maxillary Sinus Floor Defects

This case highlights the successful use of a large nasoseptal flap to repair a large maxillary sinus floor defect. Surgeons can therefore rely on this flap for repairing maxillary sinus floor defects of most sizes and locations. Laryngoscope, 134:87-91, 2024.

Allogeneic versus autogenous shell technique augmentation procedures: a prospective-observational clinical trial comparing surgical time and complication rates

OBJECTIVES

Autogenous and allogeneic blocks for shell augmentation of the jaw have shown comparable results. This observational clinical study aimed to compare both materials for shell augmentation concerning surgery time and intra- and postoperative complications.

MATERIAL AND METHODS

Bone augmentation with the shell technique using autogenous or allogenous bone was performed in 117 patients with segmental jaw atrophy. The primary study parameter was the surgical time, comparing both materials. Subsequently, intra- and postoperative complications were recorded.

RESULTS

Allogeneic (n = 60), autogenous (n = 52), or both materials (n = 5) were used. The use of allogeneic material led to a significantly shorter operation time (p < 0.001). A more experienced surgeon needed significantly less time than a less experienced surgeon (p < 0.001). An increasing number of bone shells (p < 0.001), an additional sinus floor elevation, and intraoperative complications also significantly increased the operation time (p = 0.001). Combining allogeneic and autogenous shells (p = 0.02) and simultaneous sinus floor elevation (p = 0.043) significantly impacted intraoperative complications. No correlations were found between the included variables for postoperative complications (all p > 0.05). In total, 229 implants were inserted after a healing time of 4-6 months, with a survival of 99.6% after a mean follow-up duration of 9 months.

CONCLUSIONS

Compared to the autogenous technique, allogeneic shell augmentation has a shorter surgical time and a similar rate of intra- and postoperative complications as autogenous bone. Together with its promising clinical results, this technique can be recommended.

Effectiveness, Morbidity, and Costs of Transcrestal and Lateral Sinus Floor Elevation at Sites with Different Residual Bone Heights: A Re-Analysis of Data from a Parallel-Arm Randomized Trial

PURPOSE

To comparatively evaluate transcrestal sinus floor elevation (tSFE) and lateral sinus floor elevation (lSFE) at sites with different residual bone heights (RBHs).

MATERIALS AND METHODS

A re-analysis of data from a parallel-arm, randomized trial comparatively evaluating tSFE and lSFE was performed. Within each RBH interval (< 4 mm or ≥ 4 mm), tSFE and lSFE groups were compared for chair time, surgery-related costs, morbidity, and radiographic parameters (including the proportion of the implant surface in direct contact with the radiopaque area [totCON%]).

RESULTS

The intention-to-treat (ITT) population consisted of 29 and 28 patients in the tSFE and lSFE groups, respectively. Irrespective of RBH, both tSFE and lSFE lead to a median totCON% of 100%. At sites with RBH < 4 mm, pain severity was significantly higher at days 0 and 1 in the tSFE group, with no intergroup difference in the dose of analgesics. LSFE was associated with a significantly higher frequency of bruising and greater cost. At sites with RBH ≥ 4 mm, a significantly lower frequency of postoperative signs/symptoms, less chair time, and lower costs were observed in the tSFE group.

CONCLUSIONS

The selection of tSFE or lSFE within the investigated RBH intervals seems to be supported by differences in chair time, costs, and morbidity between the two techniques. At sites with RBH < 4 mm, clinicians preferring tSFE should encourage the administration of analgesics according to a predefined plan in the early postoperative phase. At sites with RBH ≥ 4 mm, tSFE should be preferred to lSFE due to reduced chair time, costs, and morbidity.

A survey on systemic antibiotic prescription among dentists in Romandy

Antimicrobial resistance (AMR) is a significant global health threat that arises from the excessive and incorrect use of antibiotics. As key players in the evolution of AMR, medical and dental practitioners are often questioned on their indications for antibiotic prescription during daily practice. The present survey aimed to evaluate self-reported practices regarding systemic antibiotic prescription among Swiss dentists in Romandy. An electronic questionnaire was sent to 331 dentists working in the French-speaking part of Switzerland and the responses were analyzed on a three-point Likert scale. The response rate was 28%. Results showed that the main indications for antibiotic use were abscesses with systemic symptoms (89%), cellulitis (81.5%), acute sinusitis (62%) and necrotizing periodontitis (52%). Surgical procedures most frequently combined with antibiotics were sinus floor elevation (59.8%) and implant placement (60.9%). Amoxicillin was the first-choice antibiotic, and clindamycin was mostly prescribed for patients with a penicillin allergy (87%). The majority of dentists recommended prophylaxis with 2g of amoxicillin, one hour before the procedure for patients with a high risk of endocarditis (82.6%), immunodeficiency / immunosuppression (50%), or joint replacement during the last year (47.8%). Most participants (76.1%) expressed the need for specific guidelines on the use of antibiotics in dentistry. The research findings suggested antibiotic prescriptions in dentistry could profit from stricter guidelines.

Clinical and patient-centered outcomes following rehabilitation of atrophic edentulous maxilla using six implants placed simultaneously with bilateral maxillary sinus augmentation: A retrospective case series

OBJECTIVES

To evaluate treatment success, patient satisfaction, and oral health-related quality of life (OHRQoL) after rehabilitation of atrophic edentulous maxilla (AEM) with six implants placed simultaneously with bilateral maxillary sinus floor augmentation (MSFA).

MATERIALS AND METHODS

The selected patients were fully edentulous with atrophic maxillary posterior residual ridges and rehabilitated with six implants placed simultaneously with bilateral MSFA and immediate All-on-4 provisional fixed prosthesis (PFP). After 7-12 months of implant surgery, all patients have received an All-on-6 definitive fixed prosthesis (DFP). After at least one year of function with DFP, clinical and radiographic examinations were performed. Patient satisfaction was assessed through a visual analog scale (VAS). The OHRQoL before treatment (T0), during provisional (T1), and after definitive prosthesis (T2) was evaluated using OHI-14.

RESULTS

20 maxillary edentulous patients were rehabilitated with 120 implants, 20 immediate All-on-4 PFP, and 20 All-on-6 DFP. Of those, 12 patients have passed at least a year follow-up after DFP insertion and were eligible to be included in the assessment of treatment success. After a mean of 20 (12-36) months follow-up, the implant and prosthesis survival rates were 100%. The success rate at the implant level was 98.6%. The mean marginal bone loss (MBL) was 0.09 ± 0.06 mm. No prosthetic or postoperative complications, and the mean general satisfaction was (91.75 ± 7.06). There was a significant improvement in all OHIP-14 domains during the final All-on-6 prosthesis (T2) (P < 0.01).

CONCLUSIONS

Rehabilitation of atrophic edentulous maxilla using six implants with simultaneous bilateral MSFA and immediate All-on-4 PFP is a successful treatment approach associated with minimal postoperative complications and significant improvement in OHRQoL.

Surgical and prosthetic rehabilitation of siblings with Witkop tooth and nail syndrome using zygomatic implants: a familial case series of 3 patients with up to 15-year follow-up

Witkop tooth and nail syndrome is a rare, autosomal dominant type of ectodermal dysplasia that can have significant effects on dentition, including hypoplastic and malformed dentition and significantly atrophic maxillas. Endosseous implants have become one possible solution to replace missing teeth, although their use in areas where bone is sparse becomes challenging. Due to the severe atrophy of the maxillary alveolus, extensive preprosthetic surgeries including orthognathic surgery, extensive bone grafting, and sinus floor augmentations have been recommended prior to placement of endosseous dental implants. Although this treatment has shown favorable outcomes, it requires multiple surgical procedures, contributing to a prolonged treatment course and increased morbidity. An alternative treatment of atrophic maxillas in patients with ectodermal dysplasia includes the use of zygomatic implants. This familial case series discusses 3 siblings, all previously diagnosed with Witkop Syndrome, who underwent comprehensive preprosthetic surgery and prosthetic rehabilitation using zygomatic implants with a follow-up period up to 15 years.

Maxillary sinus membrane elevation and coagulum compared with maxillary sinus floor augmentation and a composite graft: A 1-year single-blinded randomized controlled trial

OBJECTIVE

The aim was to evaluate the 1-year implant outcome and patient-related outcome measures (PROMs) after maxillary sinus membrane elevation and coagulum (test) compared with maxillary sinus floor augmentation and a 1:1 ratio of autogenous bone graft from the buccal antrostomy and deproteinised porcine bone mineral (DPBM) (control).

MATERIALS AND METHODS

Forty patients (30 female, 10 male) with a mean age of 50 years (range 25-71 years) and an alveolar ridge height between 4 and 7 mm were randomly allocated to test or control. Outcome measures included survival of suprastructures and implants, implant stability quotient, health status of the peri-implant tissue, peri-implant marginal bone loss, frequency of complications and PROMs using Oral Health Impact Profile-14 combined with questionnaires assessing patient's perception of the peri-implant soft tissue, implant crown, function of the implant, and total implant treatment outcome using visual analogue scale. Mean differences were expressed with standard deviation and 95% confidence interval. Level of significance was 0.05.

RESULTS

All suprastructures and implants were well-functioning after 1-year of functional implant loading. No significant difference in any of the applied outcome measures was observed between test and control. Both treatments revealed high patient satisfaction scores and significant improvement in oral health-related quality of life.

CONCLUSION

There were no significant differences in implant outcome and PROMs between test and control, after 1-year of functional implant loading. Neither of the treatments can therefore be considered better than the other. Thus, long-term randomized controlled trials are needed before definitive conclusions can be provided about the two treatment modalities.

Alveolar antral artery: cone beam computed tomography study and clinical context

Purpose

Anastomosis between posterior superior alveolar artery and infraorbital artery can go through bony canal in the lateral wall of the maxilla. This artery is called alveolar antral artery. It can complicate lateral sinus lift procedure by bleeding and hemosinus formation or bone graft wash out. The artery can also go in soft tissues where is not visible on cone beam computed tomography. In previous studies, the relation of this artery to sinus floor or alveolar process was measured. These structures are highly unstable during lifetime and after tooth loss. The aim of this study is to study presence and relations of bony canal in the lateral maxillary wall, to characterize the group of patients which is more likely to have bone canal in the lateral maxilla. The aim and the novelty of this study is the describing of the relationship of the bony canal to the more stable structure of hard palate and describing the relation of presence of bony canal on width of maxillary sinus, and to facilitate the prediction of presence of the alveolar antral artery.

Materials

The cone beam computed tomography scans of the patients (251 in number) of the university hospital were examined for presence of alveolar antral artery (148 was fulfilled inclusion criteria), patient were characterized by gender, age, and sinus type (wide, average, narrow). The diameter of the bony canal and its relation to the level of sinus floor and hard palate were measured.

Results

The cone beam computed tomography scans of 148 patients, out of it 55 man (37,2%) and 93 women (62,8%). Bony canal containing alveolar anastomosis was found in 69 cases (57,0%). Presence of the bony canal in the lateral wall of maxillae showed statistical probability depending on age with p = 0, 064 according to Mann-Whitney test. The older patients have more likely the bony canal. The presence of the alveolar antral artery was found more likely in the wide sinuses. The hard palate level can serve as a prediction point of alveolar antral artery only in first molar and second premolar region. In accordance with previous studies the width of bony canal is significantly higher in group of man (p = 0, 015). There was found a correlation between smaller distance of bony canal from sinus floor in the presence of teeth (p = 0, 067). After tooth loss the distance between sinus floor and bony canal increases, but the distance of bony canal to hard palate level stays constant. This can be explained hypothetically so that periodontal ligaments and root surface acts as a barrier for sinus pneumatization.

Conclusion

Lateral sinus lifting in some cases can be unenviable, the knowledge about alveolar antral artery anatomy can reduce the risk of arterial bleeding. The cone-beam computed tomography is a routine examination prior to augmentation surgery and therefore the data obtained from it has an impact on clinical practice.

Comparison of 2D, 2.5D, and 3D segmentation networks for maxillary sinuses and lesions in CBCT images

BACKGROUND

The purpose of this study was to compare the segmentation performances of the 2D, 2.5D, and 3D networks for maxillary sinuses (MSs) and lesions inside the maxillary sinus (MSL) with variations in sizes, shapes, and locations in cone beam CT (CBCT) images under the same constraint of memory capacity.

METHODS

The 2D, 2.5D, and 3D networks were compared comprehensively for the segmentation of the MS and MSL in CBCT images under the same constraint of memory capacity. MSLs were obtained by subtracting the prediction of the air region of the maxillary sinus (MSA) from that of the MS.

RESULTS

The 2.5D network showed the highest segmentation performances for the MS and MSA compared to the 2D and 3D networks. The performances of the Jaccard coefficient, Dice similarity coefficient, precision, and recall by the 2.5D network of U-net +  + reached 0.947, 0.973, 0.974, and 0.971 for the MS, respectively, and 0.787, 0.875, 0.897, and 0.858 for the MSL, respectively.

CONCLUSIONS

The 2.5D segmentation network demonstrated superior segmentation performance for various MSLs with an ensemble learning approach of combining the predictions from three orthogonal planes.

Medication-related Osteonecrosis of the Jaw Induced by Regenerative Therapy in Implant Dentistry: A Scoping Review

OBJECTIVES

There is limited scientific evidence regarding the medication-related osteonecrosis of the jaw (MRONJ) induced by regenerative therapy (RT) associated with dental implant treatment. Thus, the current scoping review systematically maps the MRONJ research induced by RTs in implant dentistry and recognizes the existing gaps in knowledge.

DATA

Original studies and reviews investigating the impact of RT on the development of MRONJ were included.

SOURCES

Two reviewers independently searched the MEDLINE-PubMed and Scopus databases according to the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) extension for Scoping Review and included articles published in English up to March 31, 2023.

STUDY SELECTION

Eighteen articles that fulfilled the inclusion and exclusion criteria were included in this study. Ten mapping parameters for investigating the association of RTs with MRONJ development were examined and evaluated within the selected articles.

RESULTS

There was severely limited information regarding the procedures of RTs including; the grafting materials, surgical protocols, and success and failure rates. The RT associated with MRONJ cases was sinus floor augmentation in patients taking bisphosphonate and denosumab. Moreover, there were limited data on the implant treatment associated with RTs such as time of insertion, implant length and diameter, and loading protocol.

CONCLUSION

The current scoping review revealed that some specific RTs associated with other factors hold a potential risk of MRONJ occurrence. However, the scientific evidence is limited with many gaps. Further investigations are needed to establish an evidence-based clinical guideline for treating high-risk patients.

CLINICAL SIGNIFICANCE

Clinicians should cautiously assess the risk of MRONJ development during implant treatment planning for patients undertaking antiresorptive medications. The adverse outcome of RT procedures should not be underestimated and a complete explanation of the possible risks should be given to the patients.

Do autologous platelet concentrates (APCs) have a role in intra-oral bone regeneration? A critical review of clinical guidelines on decision-making process

In the past decades, personalized regenerative medicine has gained increased attention. Autologous platelet concentrates (APCs) such as PRP, PRGF, and L-PRF, all serving as a source of a large variety of cells and growth factors that participate in hard and soft tissue healing and regeneration, could play a significant role in regenerative periodontal procedures. This narrative review evaluated the relative impact of APCs in alveolar ridge preservation, sinus floor augmentation, and the regeneration of bony craters around teeth, both as a single substitute or in combination with a xenograft. L-PRF has a significant beneficial effect on alveolar ridge preservation (bone quality). The data for PRGF are less convincing, and PRP is controversial. L-PRF can successfully be used as a single substitute during transcrestal (≥3.5 mm bone gain) as well as 1-stage lateral window sinus floor elevation (>5 mm bone gain). For PRGF and especially PRP the data are very scarce. In the treatment of bony craters around teeth, during open flap debridement, L-PRF as a single substitute showed significant adjunctive benefits (e.g., >PPD reduction, >CAL gain, >crater depth reduction). The data for PRP and PRGF were non-conclusive. Adding PRP or L-PRF to a xenograft during OFD resulted in additional improvements (>PPD reduction, >CAL gain, >bone fill), for PRGF no data were found. Autologous platelet concentrates demonstrated to enhance bone and soft tissue healing in periodontal regenerative procedures. The data for L-PRF were most convincing. L-PRF also has the advantage of a greater simplicity of production, and its 100% autologous character.

Treatment alternatives for the rehabilitation of the posterior edentulous maxilla

Rehabilitation of the edentulous maxilla with implant-supported fixed dental prostheses can represent a significant clinical challenge due to limited bone availability and surgical access, among other factors. This review addresses several treatment options to replace missing teeth in posterior maxillary segments, namely the placement of standard implants in conjunction with maxillary sinus floor augmentation, short implants, tilted implants, and distal cantilever extensions. Pertinent technical information and a concise summary of relevant evidence on the reported outcomes of these different therapeutic approaches are presented, along with a set of clinical guidelines to facilitate decision-making processes and optimize the outcomes of therapy.

Change in Maxillary Sinus Mucosal Thickness in Patients with Preoperative Maxillary Sinus Mucosal Thickening as Assessed by Otolaryngologists: A Retrospective Study

Background and Objectives: Maxillary sinus pathologic conditions may increase the risk of complications during posterior maxillary sinus augmentation surgery. The purpose of this study was to evaluate the changes in participants with preoperative maxillary sinus mucosal thickening and to assess this factor as a preoperative risk indicator for sinusitis after maxillary dental implantation. Materials and Methods: We compared the preoperative and postoperative maxillary sinus mucosal thickness (MSMT), the distance between the maxillary sinus ostium and sinus floor (MOD), and the MSMT/MOD ratio. The participants were divided into three groups (sinus augmentation, bone grafting, and no grafting). Results: The mean preoperative MSMT was 4.3 ± 2.0 mm, and the mean MSMT/MOD ratio was 0.13 ± 0.05. No postoperative sinusitis was observed in these patients, including cases caused by anatomical variations. The mean postoperative MSMT was 4.5 ± 2.3 mm, and the mean postoperative MSMT/MOD ratio was 0.15 ± 0.06. There was no statistically significant difference between the groups at each time point (p > 0.05). Conclusions: The study found no significant change in MSMT at post-treatment evaluation, even when considering different subgroups. It underscores the importance of preoperative maxillary sinus radiographic assessments and collaboration between dentists and otolaryngologists for better outcomes in patients with preoperative maxillary sinus mucosal thickening.

Maxillary sinus floor augmentation: a review of current evidence on anatomical factors and a decision tree

Maxillary sinus floor augmentation using lateral window and crestal technique is considered as predictable methods to increase the residual bone height; however, this surgery is commonly complicated by Schneiderian membrane perforation, which is closely related to anatomical factors. This article aimed to assess anatomical factors on successful augmentation procedures. After review of the current evidence on sinus augmentation techniques, anatomical factors related to the stretching potential of Schneiderian membrane were assessed and a decision tree for the rational choice of surgical approaches was proposed. Schneiderian membrane perforation might occur when local tension exceeds its stretching potential, which is closely related to anatomical variations of the maxillary sinus. Choice of a surgical approach and clinical outcomes are influenced by the stretching potential of Schneiderian membrane. In addition to the residual bone height, clinicians should also consider the stretching potential affected by the membrane health condition, the contours of the maxillary sinus, and the presence of antral septa when evaluating the choice of surgical approaches and clinical outcomes.

Mucosal adhesion phenomenon after maxillary sinus floor elevation: A preclinical study

AIM

To describe the histological events that occur after maxillary sinus floor elevation when the elevated and undetached sinus mucosa are in close proximity or in contact with each other.

MATERIALS AND METHODS

From 76 rabbits, 152 elevated maxillary sinuses were analyzed histologically. Sites without adhesions were classified as "No proximity," whereas the adhesion stages were divided into "Proximity," "Fusion," and "Synechia stages." The width of the pseudostratified columnar epithelium and the distance between the two layers of the elevated and undetached sinus mucosae were measured at various standardized positions.

RESULTS

Thirty-one sites presenting with adhesions were found. Twelve sites were in the proximity stage," presenting cilia of the two epithelial layers that were shortened and interlinked within the mucous context. Hyperactivity of the goblet cells was also observed. In the other cases, the hyperplastic epithelium showed attempts to reach the contralateral mucosa. The 15 "fusion stage" sites presented regions with epithelial cells of the two mucosal layers that penetrated each other. Four sites presented "synechiae stages," represented by bridges of connective tissue connecting the two lamina propria.

CONCLUSIONS

Close proximity or tight contact between the elevated and undetached mucosa adhering to the bone walls might occur after maxillary sinus floor elevation. This induced hyperplasia of the epithelial cells and adhesion of the two layers until synechiae formation.

SMOKERS MAY BE SUBJECT TO A HIGHER RISK OF SCHNEIDERIAN MEMBRANE PERFORATION THAN NONSMOKERS DURING MAXILLARY SINUS AUGMENTATION

ARTICLE TITLE AND BIBLIOGRAPHIC INFORMATION

Association between smoking and Schneiderian membrane perforation during maxillary sinus floor augmentation: A systematic review and meta-analysis. Wang, X., Ma, S., Lin, L., & Yao, Q. Clinical Implant Dentistry and Related Research. 2022., 25.1: 166-176.

SOURCE OF FUNDING

National Natural Science Foundation of China, Grant/Award Number: 81801021; Hunan Provincial Health Commission, Grant/Award Number: B202308056991.

TYPE OF STUDY/DESIGN

Systematic review and meta-analysis.

Assessment of the relationships between posterior root apices and the maxillary sinus floor: a comparison of panoramic radiography and cone beam computed tomography

The aim of this study was to evaluate the relationships between the apices of posterior teeth and the maxillary sinus floor, comparing the results of assessments performed with panoramic radiography and cone beam computed tomography (CBCT). This retrospective cross-sectional study consisted of 96 participants with a total of 302 maxillary posterior teeth. On both panoramic radiographs and corresponding CBCT images, 735 roots were classified into 3 categories according to their topographic relationship with the maxillary sinus: class 1, clear, distinct distance between the root tips and the floor of the sinus; class 2, roots adjacent to the floor of the maxillary sinus; or class 3, roots protruding into the maxillary sinus cavity. Panoramic radiographic signs of root protrusion into the sinus (class 3) were categorized as projection, discontinuity, missing lamina dura, darkening, or kinking. The observed data were analyzed using statistical software, and the Cohen κ coefficient was calculated. The level of significance was set at P < 0.05. Multiple logistic regression was performed to identify the predictive radiographic signs of protrusion into the sinus. The overall correlations between panoramic radiography and CBCT classifications were 90.8%, 66.8%, and 47.1% for the class 1, class 2, and class 3 categories, respectively. The radiographic signs of projection and darkening were significant predictors of root protrusion (P < 0.05). Panoramic radiography is reliable for assessing root posi¬tions when there is a clear distance between the roots and the floor of the maxillary sinus. However, when the roots are in contact with or have protruded into the sinus on panoramic images, the results are not definitive, and CBCT should be performed.

Patterns of senescence and apoptosis during development of branchial arches, epibranchial placodes, and pharyngeal pouches

BACKGROUND

Many developmental processes are coregulated by apoptosis and senescence. However, there is a lack of data on the development of branchial arches, epibranchial placodes, and pharyngeal pouches, which harbor epibranchial signaling centers.

RESULTS

Using immunohistochemical, histochemical, and 3D reconstruction methods, we show that in mice, senescence and apoptosis together may contribute to the invagination of the branchial clefts and the deepening of the cervical sinus floor, in antagonism to the proliferation acting in the evaginating branchial arches. The concomitant apoptotic elimination of lateral line rudiments occurs in the absence of senescence. In the epibranchial placodes, senescence and apoptosis appear to (1) support invagination or at least indentation by immobilizing the margins of the centrally proliferating pit, (2) coregulate the number and fate of Pax8+ precursors, (3) progressively narrow neuroblast delamination sites, and (4) contribute to placode regression. Putative epibranchial signaling centers in the pharyngeal pouches are likely deactivated by rostral senescence and caudal apoptosis.

CONCLUSIONS

Our results reveal a plethora of novel patterns of apoptosis and senescence, some overlapping, some complementary, whose functional contributions to the development of the branchial region, including the epibranchial placodes and their signaling centers, can now be tested experimentally.

The healing capacity and osteogenesis pattern of demineralized dentin matrix (DDM)-fibrin glue (FG) compound

Demineralized dentin matrix (DDM) is an osteoconductive and osteoinductive material that has been successfully used in sinus floor augmentation and alveolar ridge augmentation in clinical applications. It releases bone morphogenetic proteins (BMPs) and other growth factors, making DDM a suitable grafting material. However, the granular particle of DDM makes it difficult to anchor into the bone defect area. The aim of this study was to investigate the biological effects and osteoinductivity of the combination of DDM and Fibrin Glue (FG) at an optimal ratio on bone healing from a critical bone defect in an animal model. The mouse osteoblastic cell line (MC3T3-E1) was co-cultured with various ratios of DDM and FG to examine their effects on osteoblast proliferation and differentiation, as indicated by alkaline phosphatase (ALP) activity, osteocalcin (OC) production and mineralized nodules formation. The optimal ratio was then chosen for further study with a rabbit calvarial defective model, in which they were implanted with DDM or DDM-FG1 (1 g: 0.1 ml) and DDM-FG2 (1 g: 0.5 ml) compounds, or left blank for 2, 4, 8 and 12 weeks to investigate soft tissue and new bone regeneration. Micro-CT and histology analysis were used to evaluate the total grafting properties according to the different healing periods. The result from in vitro studies demonstrated that the ratio of 1:0.1 induced more ALP activity and mineralized nodules, while the ratio of 1: 0.5 (DDM-FG combined) induced more osteocalcin (OC) at specific time points. In the animal model, the 3D new bone volume in all DDM-FG treatment groups was significantly greater than that in the blank group at 2, 4, 8 and 12 weeks. Furthermore, the new bone volume was greater in DDM-FG2 when compared to the other groups during the early weeks of the healing period. In histological analysis, clusters of osteoblasts were formed adjacent to the DDM particles, and newly formed bone was observed in all groups, suggesting an osteoinductive property of DDM. Moreover, the greater new collagen synthesis observed at 4 weeks suggested that early bone healing was induced in the DDM-FG2 group. This study demonstrated that at an optimal ratio, the DDM-FG compound enhances osteogenic activities and bone regeneration.

Digitally Guided Lateral Sinus Floor Elevation With Simultaneous Implant Placement: 3 Case Reports With Technical Considerations

A sinus floor elevation via lateral window (LSFE) is one of the most widely used bone augmentation procedures for implant therapy in the posterior area of the maxilla. Locating and preparing a correct opening window on the lateral sinus wall is a key step of this procedure. Conventionally, the surgeon designs and locates the window after the flap is reflected based on the information obtained from cone-beam computed tomography (CBCT) images or other diagnostic aids. Nevertheless, in spite of the advancements in CBCT imaging, clinicians may still experience hardships in situating and procuring meticulous access to the maxillary sinus by using CBCT alone. Therefore, in cases requiring an LSFE simultaneous to implant placement, a maxillary sinus surgical guide has been tested and reported to be the amiable method to be utilized as a conjunct to prevent unpredictable consequences according to its application in implying both the direction for the implant and the location of the lateral window. This article presents 3 clinical cases with a fully digital approach to guide the opening of the lateral wall of the maxillary sinus as well as the simultaneous placement of a single implant in an ideal 3D position. Based on the CBCT images and intraoral scan, a surgical guide was fabricated based on 3D software. During surgery, this teeth-supported template can be placed intraorally, guiding sinus window opening preparation. This technique makes the sinus window opening procedure simple and predictable, reduces surgical time and the risk of complications, and allows the placement of the implant in the ideal 3D position.

Evaluation of the relation between the maxillary sinus and the posterior teeth using digital panoramic radiography

This research aimed to determine the relationship between the maxillary posterior teeth and maxillary sinus floor (MSF), as well as the impact of nearby tooth loss on the space between MSF and posterior maxillary roots. A number of 120 digital panoramic radiographs were obtained from the archives of several clinics in Al-Najaf, Iraq, with the overall teeth examined in these radiographs including 236 of the 1st premolars, 227 of the 2nd premolars, 227 of the 1st molars, and 231 of the 2nd molars, from the right and left sides. The distances between the apices of the teeth and the maxillary sinus were determined. There are three categories of relationships between upper posterior teeth roots and MSF. These include type Os (root apex exists below or outside MSF), Type Co (root apex in contact with the MSF), and Type Is (root apex above or inside MSF). Type Os is the most encountered among premolars, Type Co is mostly encountered among the 2nd molars, and Type Is, in the 1st and 2nd molars. The study finds no correlation between age, gender, and the distribution of maxillary posterior tooth roots attached to the MSF. The first premolars were the furthest from MS, while the first molars were the closest. The most frequent link between maxillary molar roots and the MS was the Co-relation for the 2nd maxillary molar and the Is relation for the 1st maxillary molar. There is a non-significant decrease in the distance between the apices of the 1st maxillary premolar, 2nd maxillary premolar, and 1st maxillary molar and the MS before and after extraction.

Cone-beam computed tomographic analysis of maxillary sinus septa among Yemeni population: a cross-sectional study

BACKGROUND

Maxillary sinus septa increase perforation risk of Schneiderian membrane during the sinus floor elevation (SFE). Cone Beam Computed Tomography (CBCT) allows for a more precise assessment of the septal position; thus, preoperative CBCT analysis is substantial to avoid possible complications. This study aims to investigate the 3D characteristics of the maxillary sinus septa based on CBCT images. To our knowledge, no study reported the CBCT-based investigation for the sinus septa among Yemeni population.

MATERIALS AND METHODS

This is a retrospective cross-sectional analysis of 880 sinus CBCT images 440 patients. The septa prevalence, locations, orientations, morphology, and associated factors were analyzed. The effect of age, gender, and dental status on the sinus septa and the relationship between sinus membrane pathology and sinus septa were also analyzed. Anatomage (Invivo version 6) was used for CBCT images analysis. Descriptive and analytical statistics were performed, and a P-value < 0.05 was significantly considered.

RESULTS

The maxillary sinus septa were found among 63.9% of patients and 47% of sinuses. The average septa height was 5.2 mm. 15.7% of patients had septa in the right maxilla, 18% in the left, and 30.2% in both. Gender, age, and dental condition had no influence on the presence of septa, and septa presence did not influence sinus membrane pathology. Many septa originated from the floor (54.5%), located in the middle (43%), with coronal orientation (66%) and complete configuration (58.2%).

CONCLUSION

Based on our findings, the septa prevalence, locations, orientations, and morphology were significant and equivalent to the highest recorded in the literature yet. Thus, when sinus floor elevation is planned, CBCT imaging of the maxillary sinus is recommended for safe dental implantation.

Effect of the implant apical exposure and coverage < or ≥ 2 mm bone graft on transcrestal sinus floor elevation: a 1- to 7-year retrospective cohort study

OBJECTIVES

This study aimed to analyze the effect of the apex coverage by the bone graft, including exposure and coverage less than or greater than 2 mm on implant survival rate and peri-implant bone and soft tissue remodeling.

MATERIALS AND METHODS

A total of 264 implants in 180 patients who had undergone transcrestal sinus floor elevation (TSFE) with simultaneous implant placement were included in this retrospective cohort study. Radiographic assessment was used to categorize the implants into three groups based on apical implant bone height (ABH): ≤ 0 mm, < 2 mm, or ≥ 2 mm. The implant survival rate, peri-implant marginal bone loss (MBL) during short-term (1-3 years) and mid- to long-term (4-7 years) follow-up, and clinical parameters were used to evaluate the effect of implant apex coverage after TSFE.

RESULTS

Group 1 had 56 implants (ABH ≤ 0 mm), group 2 had 123 implants (ABH > 0 mm, but < 2 mm), and group 3 had 85 implants (ABH ≥ 2 mm). There was no significant difference in the implant survival rate between groups 2 and 3 compared to group 1 (p = 0.646, p = 0.824, respectively). The MBL during short-term and mid- to long-term follow-up indicated that apex coverage could not be considered a risk factor. Furthermore, apex coverage did not have a significant effect on other clinical parameters.

CONCLUSIONS

Despite limitations, our study found that implant apex coverage by the bone graft, including exposure and coverage levels less than or greater than 2 mm, did not significantly affect implant survival, short-term or mid- to long-term MBL, or peri-implant soft tissue outcomes.

CLINICAL RELEVANCE

Based on 1- to 7-year data, the study suggests that implant apical exposure and coverage levels of less than or greater than 2 mm bone graft are both valid options for TSFE cases.

Prevalence and pattern of proximity of maxillary posterior teeth to maxillary sinus with mucosal thickening: A cone beam computed tomography based retrospective study

Context

Odontogenic sinusitis is a prevalent but frequently unrecognized condition, and periapical pathologies of maxillary posterior teeth are accused as one of the main causative factors.

Aim

This study aimed to evaluate the relationship between the periapical status of maxillary posterior teeth and its proximity to the maxillary sinus floor in the occurrence of incidental sinus pathologies using cone-beam computed tomography (CBCT).

Methodology

CBCT scans of 118 patients of age range 18-77 years were evaluated retrospectively to determine the relationship of maxillary posterior teeth to sinus floor in which vertical relationship was assessed using modified Kwak's classification and periapical status using CBCT periapical index. Statistical analysis was performed using SPSS statistics software.

Results

Of all 227 sinuses examined, 56.8% showed pathological changes, with mucosal thickening being the most common. More than 50% (50.2%) of sinuses were associated with periapical lesions of at least one maxillary posterior tooth based on evidence of pathological mucosal thickening. The presence of pathologic mucosal thickening was also significantly related (P < 0.05) to the presence of periapical pathologies. There was a significant association between tooth position and pathological sinus mucosal thickening, especially with second molars, first molars, and second premolars, respectively (P < 0.05). Second molar involvement was the most significant (P < 0.05).

Conclusion

The present study established a positive association between periapical disease status of maxillary posteriors and maxillary sinus mucosal thickening. Maxillary second premolar and first and second molars pathologies can significantly affect the maxillary sinus compared to other maxillary posterior tooth. CBCT proved to be an efficient imaging modality in detecting these changes.

Characteristics of maxillary sinus ostia and their correlation with anatomic variations of the osteomeatal complex: Indications for sinus floor elevation

Background

Knowledge of the anatomy and variations of the maxillary sinus is essential for reducing oral surgery complications, such as sinus floor elevation, and increasing surgery success. The CBCT images of 385 patients were examined.

Materials and Methods

The prevalence, localization, and height of PMO (Primer Maxillary Ostium) and AMO (Accessory Maxillary Ostium) were evaluated with respect to sex, dentition, dental treatment, Schneiderian membrane (SM) thickness, concha bullosa, Haller Cells, and septal deviation.

Results

The PMO was present in 87.3% of all patients. Further analysis showed that the mean PMO diameter was 1.42 ± 0.62 mm. Although 11.6% of the PMO was in the inferior region, 60.4% was in the middle and 28% in the superior region. The effect of age and SM on the height and diameter of the PMO was found to be statistically significant. An AMO was present in 20% of the CBCT images. The mean AMO diameter was 2.55 ± 1.25 mm. Although 45.4% of the AMO was in the inferior region, 48% was in the middle and 6.6% was in the superior region. Moreover, SM thickness seemed to influence the height. A significant positive relationship was found between the PMO and AMO height. Also, a significant relationship was observed between the presence of the AMO and septum deviation.

Conclusion

The presence of the AMO, PMO diameter, and height should be added to the preoperative evaluation criteria for the success of sinus floor evaluation. Specifically, sinonasal and demographic conditions should be carefully examined preoperatively for the long-term success of the surgery.

Sinusitis Following Reduction Malarplasty

The aim of this paper was to search for reported cases of sinus infection following reduction malarplasty and present guidelines for the prevention of sinusitis. Two cases of maxillary sinusitis that developed after reduction malarplasty has been reported, which were treated with endoscopic sinus surgery. Histologically, thickness of the mucosal lining of the maxillary sinus (Schneiderian membrane) was 0.41 mm at sinus floor, and 0.38 mm at 2 mm above the floor. In functional endoscopic sinus surgery (FESS), the uncinate process is removed, exposing the hiatus semilunaris. The anterior ethmoid air cells are opened, allowing better ventilation but leaving the bone covered with mucosa. FESS improves the function of the osteomeatal complex and therefore provides better ventilation of the sinuses. In odontogenic maxillary sinusitis, regeneration of the mucosal lining (ciliated epithelium regeneration and bone healing) was achieved in 1.4±1.2 years after modified endoscopic sinus surgery. In in zygomatic implant surgery, 12.3% patients presented maxillary sinusitis, and the most common treatment was antibiotics alone or combined with FESS. To prevent sinusitis after reduction malarplasty, accurate osteotomy and fixation are needed, especially when using only an intraoral incision. After surgery, radiological examinations (Water's view, computed tomography if needed) should be performed as part of follow-up. Prophylactic antibiotics (macrolides) are recommended for 1 week if the sinus wall is opened. If swelling or air-fluid level persists, re-exploration and drainage should be performed. In patients with risk factors such as age, comorbidities, smoking, nasal septal deviation, or other anatomical variants, simultaneous FESS is suggested.

Influence of Smoking on Periodontal and Implant Therapy: A Narrative Review

BACKGROUND

smoking is considered the most modifiable risk factor for periodontal disease.

OBJECTIVE

the aim of this narrative review is to emphasize the effect of smoking on periodontal and implant therapy.

METHODS

The authors reviewed the literature reporting the clinical outcomes of smoking on periodontal surgical and nonsurgical treatment. The impact of smoking on implant therapy and sinus lifting procedures were also reviewed.

RESULTS

Periodontal and implant therapy outcomes are adversely affected by smoking. Smokers respond less favorably to periodontal therapy and periodontal flap procedures as compared to nonsmokers. Clinical outcomes for smokers are 50-75% worse than for nonsmokers. Studies reveal that smokers experience a significantly lower reduction in pocket depth compared to nonsmokers as well as less bone growth after treating infra-bony defects with guided tissue regeneration. The relative risk of implant failure is significantly higher in patients who smoke 20 cigarettes or more per day compared to nonsmokers. Additionally, smoking has also been shown to increase postoperative wound dehiscence and infection rates following sinus floor elevation. Longitudinal studies on smoke cessation have shown a reduction in bone loss and probing depths for periodontitis patients after cessation compared to those who smoke.

CONCLUSION

Smoking cessation can reduce probing depths and improve clinical attachment after nonsurgical periodontal therapy. There is insufficient evidence regarding the effect of smoking on peri-implantitis, as well as the loss of implants in the long-term.

Comparison of calcium sulfate and tricalcium phosphate in bone grafting after sinus lifting for dental implantation: A randomized controlled trial

BACKGROUND

Maxillary sinus grafting is considered the most common surgical technique to secure a sufficient bone height for placing dental implants. It is carried out either by making a bony window in the lateral wall of the maxillary sinus (the external procedure) or through the alveolar entrance technique by using alveolar osteotomes (the internal procedure), depending on the quality and quantity of the remaining bone.

OBJECTIVES

The aim of the present study was to compare radiologically the amount of bone gain (an increase in bone dimensions) and bone reduction (the loss of the graft volume) obtained by using tricalcium phosphate (TCP) and calcium sulfate (CS) grafts mixed with advanced platelet-rich fibrin (A-PRF).

MATERIAL AND METHODS

Nine patients (18 maxillary sinuses) participated in this study, all of whom had bilateral edentulism involving the premolar/molar areas and a bone height of 0.5-5 mm between the sinus floor and the alveolar ridge. Two biomaterials were used in the sinus augmentation procedures. Each patient underwent a bilateral maxillary sinus lift with the use of different bone graft materials - with CS mixed with A-PRF used on one side, and TCP mixed with A-PRF on the other side. The grafting site was selected randomly. Afterward, bone gain and bone reduction were evaluated at the grafting site by using cone-beam computed tomography (CBCT).

RESULTS

The mean bone gain on the side treated with TCP mixed with A-PRF was 7.532 ±1.150 mm, and on the side treated with CS mixed with A-PRF side it was 7.961 ±2.781 mm. The comparison of bone gain and bone reduction between the 2 groups showed no statistically significant differences at a 6-month follow-up.

CONCLUSIONS

Using CS or TCP mixed with A-PRF was beneficial and safe in the two-stage maxillary sinus lifting procedure. A sufficient amount of bone was obtained for dental implantation.

Effect of Maxillary Sinus Anatomy on Bone Gain After Lateral Window Sinus Floor Elevation: A Case-Control Study

Purpose: To evaluate the effect of maxillary sinus anatomy on sinus floor elevation (SFE) operations performed with the lateral window approach. Materials and Methods: CBCT and digital panoramic radiographs were evaluated before and at least 6 months after maxillary sinus floor elevation (SFE) operations performed in 33 maxillary sinus regions in 26 patients. Maxillary sinus volume, grafted volume (GV), sinus width (SW), residual bone height (RBH), and vertical graft resorption (VGR) were calculated. The effects of RBH and SW on GV and VGR were evaluated statistically. Results: The mean GV values in the maxillary sinuses classified as narrow, average, and wide were 2.60 ± 0.57, 3.44 ± 0.65, and 3.70 ± 0.64 cm³, respectively. The mean VGR was 2.12 ± 1.67 mm, and in the sites classified as narrow, average, and wide, the mean VGR values were 1.50 ± 0.79, 1.58 ± 1.28, and 3.46 ± 2.06 mm, respectively. A statistically significant difference in GV and VGR was found between the SW groups. The mean posterior maxillary RBH was 2.30 ± 1.05 mm, and 17 and 16 sinuses were classified as ≤ 2 and > 2 mm, respectively. There was no statistically significant difference in the effect of RBH on GV or VGR. Conclusion: Although posterior maxillary RBH did not affect new bone formation in the sinuses grafted only with hydroxyapatite-derived inorganic bovine bone, with increasing SW, the GV decreased and the VGR increased.

Clinical and patient-reported outcomes of tissue engineering strategies for periodontal and peri-implant reconstruction

Scientific advancements in biomaterials, cellular therapies, and growth factors have brought new therapeutic options for periodontal and peri-implant reconstructive procedures. These tissue engineering strategies involve the enrichment of scaffolds with living cells or signaling molecules and aim at mimicking the cascades of wound healing events and the clinical outcomes of conventional autogenous grafts, without the need for donor tissue. Several tissue engineering strategies have been explored over the years for a variety of clinical scenarios, including periodontal regeneration, treatment of gingival recessions/mucogingival conditions, alveolar ridge preservation, bone augmentation procedures, sinus floor elevation, and peri-implant bone regeneration therapies. The goal of this article was to review the tissue engineering strategies that have been performed for periodontal and peri-implant reconstruction and implant site development, and to evaluate their safety, invasiveness, efficacy, and patient-reported outcomes. A detailed systematic search was conducted to identify eligible randomized controlled trials reporting the outcomes of tissue engineering strategies utilized for the aforementioned indications. A total of 128 trials were ultimately included in this review for a detailed qualitative analysis. Commonly performed tissue engineering strategies involved scaffolds enriched with mesenchymal or somatic cells (cell-based tissue engineering strategies), or more often scaffolds loaded with signaling molecules/growth factors (signaling molecule-based tissue engineering strategies). These approaches were found to be safe when utilized for periodontal and peri-implant reconstruction therapies and implant site development. Tissue engineering strategies demonstrated either similar or superior clinical outcomes than conventional approaches for the treatment of infrabony and furcation defects, alveolar ridge preservation, and sinus floor augmentation. Tissue engineering strategies can promote higher root coverage, keratinized tissue width, and gingival thickness gain than scaffolds alone can, and they can often obtain similar mean root coverage compared with autogenous grafts. There is some evidence suggesting that tissue engineering strategies can have a positive effect on patient morbidity, their preference, esthetics, and quality of life when utilized for the treatment of mucogingival deformities. Similarly, tissue engineering strategies can reduce the invasiveness and complications of autogenous graft-based staged bone augmentation. More studies incorporating patient-reported outcomes are needed to understand the cost-benefits of tissue engineering strategies compared with traditional treatments.

[History of frontal sinus surgery and current view of the problem. Part 2]

Surgical treatment of inflammatory diseases of the frontal sinus is one of the biggest challenges of modern otorhinolaryngology. Close proximity of the frontal sinus and frontal sinus drainage pathways to the skull base, the orbit and the anterior ethmoid artery, great limitations with its visualization and instrumentation, and high risk of the frontal recess scarring cause difficulties in either endoscopic or external approaches to the frontal sinus. At the same time endoscopic approach to the frontal sinus is considered as preferred method of frontal sinusitis surgical treatment by majority of peers nowadays. The introduction of extended approaches to the frontal sinus pathology treatment with frontal sinus floor and interfrontal sinus septum drill-out as well as superior septectomy with common drainage pathway formation gave an opportunity to greatly decrease a rate of indications for external frontal sinus procedures. In this paper historical backgrounds of endonasal approaches to frontal sinuses are presented, current controversies in proper selection of extent and methods of the frontal sinus surgery are analyzed and endoscopic as well as external approaches to frontal sinuses are summarized.

[Impact of maxillary sinus floor on the mesial movement of maxillary first molar]

PURPOSE

To investigate the impact of maxillary sinus floor on the mesial movement of maxillary first molar.

METHODS

Orthodontic patients with maxillary first premolars extracted were selected. Their maxillary first molars were divided into case group and control group according to whether their roots were in contact with the maxillary sinus floor. The case group was further divided into three subtypes according to the depth of the root extruded into the maxillary sinus. A total of 64 maxillary first molars from 32 patients were enrolled in this study, including 34 in the case group (five in subtype Ⅱ, fourteen in subtype Ⅲ, and 15 in subtype Ⅳ) and 30 in the control group. The mesial movement distance of each root and crown and the inclination of each root long axis were measured, and resorption of each root was evaluated. SPSS 22.0 software package was used for data analysis.

RESULTS

After orthodontic treatment, the mesial movement distance of roots from both groups were all lager than 2 mm. The mesial movement distance of the crown was not statistically different between the two groups (P＞0.05), while the mesial movement distance of the roots in the control group was significantly larger than in the case group（P＜0.05）. Inclined movement towards the mesial direction was found in both groups, and the inclination angle was significantly larger in the case group（P＜0.05）. The inclination angle of the first molars in the subtype Ⅳ was significantly larger than that in the subtype Ⅲ and the control group. Most of the maxillary first molars from both groups had no obvious root resorption（P＞0.05）.

CONCLUSIONS

With the proper force system, maxillary first molars with roots extruded into the maxillary sinus floor can be moved mesialy with mild or no root resorption, while a larger inclination can be found compared with maxillary first molars without root extruding into the maxillary sinus floor. The deeper the root extruding into the maxillary sinus, the larger the inclination angle will be.

Spatial Relationship of Maxillary Posterior Teeth with Maxillary Sinus Floor in Sagittal, Coronal and Axial Planes by Using Cone-Beam Computed Tomography in a Subpopulation of Central India

Inadvertent perforation of the root apex during endodontic procedure in maxillary posterior teeth may unnecessarily invite the complications of sinusitis or inflammatory responses. This becomes even more important when performing endodontic surgical procedures. Thus, it is mandatory to have the precise knowledge of anatomic structures which are in close proximity to the apex of roots and its variations among different geographic area. This retrospective observational study was performed in the Central India to assess the spatial relationships between the maxillary second pre-molar (sPM), maxillary first molar (M1), maxillary second molar (M2) with the maxillary sinus floor using cone beam computed tomography (CBCT) in all three axial, sagittal and coronal sections from year 2016 to 2021. Three hundred and sixty teeth were examined through sixty full volumes CBCT scans of the patients in between year 2016-2021 in Indore, (MP, India). The Distances (D) between the examined roots and the sinus floor, were evaluated using CBCT in all three sections, and grouped in 7 classes. To simplify, Class 1 and 2 were grouped as Negative Configuration where apices are protruding into sinus floor, Class 3 as Zero and Class 4-7 as Positive configuration. The data were analyzed statistically using SPSS system. The prevalence of class 1 and 2 (negative configuration) was the highest for the Palatal of M1 (16.67%) followed by Distobuccal of M1 (13.34%). The prevalence of class 3 that is Zero configuration was the highest for the Mesiobuccal of M2 (63.33%). The results suggested all the three teeth roots showed closed proximity with sinus floor, closest relationship with the sinus floor was seen in palatal of M1 in this study.

Presence of Periopathogens in Sinus Floor Augmentation Sites: A Cohort Study

PURPOSE

To investigate the effects of periopathogens on bone grafts for maxillary sinus floor augmentation and implant survival.

MATERIALS AND METHODS

A cohort study was designed. Samples from maxillary sinus floor augmentation sites and from periodontal pockets in adjacent teeth of the same patients were collected during the surgery and following periodontal maintenance and plaque removal. Polymerase chain reaction (PCR) was performed by an external lab service for analysis of the following periopathogens: Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythia, and Treponema denticola. Correlations between the presence of periopathogens in sinus sites and periodontal pockets in adjacent teeth and the clinical findings (bone and implant survival) were studied.

RESULTS

A total of 23 patients were suitable for study inclusion. Periopathogens were found in sinus sites in 6 patients (26%) and in tooth sites in 15 patients (65%). There was low correlation for the presence of periopathogens between tooth sites and sinus sites and for complications.

CONCLUSION

The presence of periopathogens as revealed by PCR was lower in sinus sites compared with tooth sites. Their presence neither caused bone pathology nor affected dental implant survival. The presence of periopathogens in sinus sites is inevitable even under periodontal maintenance. Although its presence did not endanger implant survival, future studies are recommended for studying this issue. Further analyses of the presence of periopathogens in cases of bone resorption at the apex of dental implants inserted into sites of augmented sinuses are warranted.

[Clinical practice of infratemporal fossa benign tumor endoscopic transnasal/oral surgery in 36 patients]

Objective:According to the characteristics of endoscopic transnasal and transoral surgery for infratemporal fossa tumors, we divided and named subzones of the infratemporal fossa, to explore the approaches of endoscopic transnasal and transoral surgery for infratemporal fossa tumors, and to analyze their advantages and disadvantages. Methods:We retrospectively analyzed the clinical data of 36 patients with benign tumors of infratemporal fossa successfully resected through nose or mouth under endoscope, summarized and analyzed the localization characteristics of these tumors in infratemporal fossa, and made a subzone naming rule of infratemporal fossa. We also summarized the selection principles, advantages and disadvantages of endoscopic transnasal and transoral surgical approaches. Results:The infratemporal fossa area is divided into ABC area. Area A is the fat pad area posterolateral of maxillary sinus. Area B is further divided into B1 （above the plane of maxillary sinus floor, anterior styloid process）, B2 （below the plane of maxillary sinus floor, anterior styloid process）, and B3 （posterior styloid process to anterior vertebra）; Area C is retropharyngeal and eustachian tube area. The location of the tumor in the infratemporal fossa determines the choice of transnasal and transoral approaches. All tumors were completely removed, and no tumor recurred during the follow-up. A few patients had temporary local sensory function decline, and recovered during the follow-up. Conclusion:The infratemporal fossa region naming rule according to the characteristics of endoscopic transoral and transnasal surgery approach is simple and practical, which can effectively guide the operation of the infratemporal fossa region and has clinical application value.