Ultrasonography-Derived Elasticity Estimation of Live Porcine Oral Mucosa.

OBJECTIVES: To investigate the biomechanical properties of porcine oral tissues with in vivo ultrasonography and to compare the difference between oral alveolar mucosa and gingival tissue concerning compressional and tensile mechanical strain. MATERIALS AND METHODS: Sinclair minipigs (6 females and 4 males, 6 to 18 months of age) were anesthetized for ultrasonography. In vivo high-frequency tissue harmonic ultrasound (12/24 MHz) cine-loops were obtained while inducing mechanical tissue stress (0 to 1 N). Post-processing strain analysis was performed in a cardiac speckle tracking software (EchoInsight®). Region of interest (ROI) was placed for gingival and alveolar mucosa tissues for longitudinal (compressional) and tensile strain analyses. A calibrated gel pad was employed to determine the absolute force (pressure) for the measured tissue strain response function. The resulting elasticity data was statistically analyzed using custom Matlab scripts. RESULTS: In total, 38 sonography cine-loops around the third premolars were included in the investigation. The longitudinal strain of alveolar mucosa ε AM L was found to be significantly (P < .05) larger than that of gingiva ε G L . Across the measured force range, ε AM L ~ 1.7 × Îµ G L . Significant differences between alveolar mucosa and gingiva tissues were found for all forces. The tensile strain of the alveolar mucosa ε AM T was found to be ~2 × Îµ G T (on the epithelial surface of the gingiva). Both were statistically significantly different for forces exceeding ~0.08 N. At depth, that is, 500 and 1000 µm below the epithelial surface, the gingiva was found to have less ability to stretch contrary to the alveolar mucosa. Gingival tissue at 500 µm depth has significantly less tensile strain than at its surface and more than at 1000 µm depth. In contrast, the tensile strain of alveolar mucosa is largely independent of depth. CONCLUSION: Ultrasonography can reveal significant differences in oral alveolar mucosal and gingival elastic properties, such as compressional and tensile strain. Under minute forces equivalent to 10 to 40 g, these differences can be observed. As dental ultrasound is a chairside, and noninvasive modality, obtaining real-time images might soon find clinical utility as a new diagnostic tool for the objective and quantitative assessment of periodontal and peri-implant soft tissues in clinical and research realms. As ultrasound is a safe modality with no known bioeffects, longitudinal monitoring of areas of concern would be particularly attractive.

Doppler ultrasonographic evaluation of tissue revascularization following connective tissue graft at implant sites.

AIM: To assess the Doppler ultrasonographic tissue perfusion at dental implant sites augmented with connective tissue graft (CTG) using coronally advanced flap (CAF) or tunnel technique (TUN). MATERIALS AND METHODS: Twenty-eight patients presenting with isolated healthy peri-implant soft-tissue dehiscence (PSTD) were included in this randomized clinical trial. PSTDs were treated with either CAF + CTG or TUN + CTG. Ultrasound scans were taken at baseline, 1 week, 1 month, 6 months and 12 months. Tissue perfusion at the mid-facial, mesial and distal aspects of the implant sites was assessed by colour Doppler velocity (CDV) and power Doppler imaging (PDI). Early vascularization of the graft and the flap at 1 week and at 1 month were evaluated via dynamic tissue perfusion measurements (DTPMs), including flow intensity (FI), mean perfusion relief intensity (pRI) and mean perfused area (pA). RESULTS: Regression analysis did not reveal significant differences in terms of mid-facial CDV and PDI changes between CAF and TUN over 12 months (p > .05), while significant differences between the two groups were observed at the interproximal areas (p < .001 for both CDV and PDI changes). Higher early DTPMs were observed at the TUN-treated sites in terms of mean FI of the graft (p = .027) and mean FI (p = .024) and pRI of the flap (p = .031) compared with CAF-treated sites at 1 week. Assessment of the FI direction showed that CTG perfusion at 1 week and at 1 month mainly occurred from the flap towards the implant/bone. Early tissue perfusion outcomes were found to be associated with the 12-month mean PSTD coverage and mucosal thickness gain. CONCLUSIONS: Doppler ultrasonography shows tissue perfusion changes occurring at implant sites augmented with CTG. The main differences in tissue perfusion between CAF and TUN were observed at the interproximal sites, with early perfusion associated with clinical and volumetric outcomes at 12 months.

Coronally advanced flap versus tunnel technique for the treatment of peri-implant soft tissue dehiscences with the connective tissue graft: A randomized, controlled clinical trial.

AIM: To evaluate the efficacy of coronally advanced flap (CAF) versus tunnel technique (TUN) in covering isolated mid-facial peri-implant soft tissue dehiscences (PSTDs). MATERIALS AND METHODS: Twenty-eight participants presenting with isolated non-molar implants exhibiting PSTDs were enrolled and randomized to receive either CAF or TUN, both with a connective tissue graft (CTG). The primary outcome of the study was the percentage of mean PSTD coverage at 12 months. Secondary endpoints included the frequency of complete PSTD coverage, changes in keratinized mucosa width (KMW) and horizontal mucosal thickness (MT), as assessed with transgingival probing, 3D optical scanning and ultrasonography, professional aesthetic evaluation and patient-reported outcome measures (PROMs). RESULTS: At 12 months, the mean PSTD coverage of the CAF and TUN groups was 90.23% and 59.76%, respectively (p = .03). CAF-treated sites showed a substantially higher frequency of complete PSTD coverage (p = .07), together with significantly greater gain of KMW (p = .01), increase in MT (p = .02), volumetric gain (p < .01) and professional aesthetic outcomes (p = .01). Both interventions showed an improvement in patient-reported aesthetics and a reduction of the anxiety related to the appearance of the implant compared to baseline, with the CAF group obtaining significantly higher scores (p = .03 for both PROMs). CONCLUSIONS: CAF + CTG resulted in superior PSTD coverage outcomes, greater gain in KMW and MT, and better PROMs than TUN + CTG for the treatment of isolated PSTDs (ClinicalTrials.gov NCT03498911).

Preliminary Experience in Transducer Preparation for Intraoral Imaging.

Intraoral scanning must meet a stringent infection control standard because of contact with the oral mucosa. A preparation protocol is thus presented for increased inquiries about intraoral scanning requirements. Materials required for such a preparation include: a single-use bubble-free gel packet, a gel standoff pad, and a transducer probe cover. Postscan reprocessing of the ultrasound transducer requires high-level disinfection. Examples for proper and improper use are provided as well as limitations of this preparation protocol and recommendations for future development. This guidance meets the current infection control standard and may guide the user to obtain consistent ultrasound image quality.

Life satisfaction and peace of mind among dentists: a cross-sectional study.

OBJECTIVES: This study sought to identify the factors associated with the life satisfaction and peace of mind (PoM) of dentists not in full-time clinical training. MATERIALS AND METHODS: Cross-sectional questionnaires were distributed to dentists in Taiwan to collect their life satisfaction, PoM, sociodemographic data, and dental career-related characteristics. Life satisfaction was measured using a 5-item Satisfaction with Life Scale. PoM was measured using a 7-item Peace of Mind Scale. Descriptive statistics and multiple linear regression models were estimated to explore potential associations between the two scales and the examined factors. RESULTS: A total of 1196 dentists (45.6% female; mean age = 44.12) completed the questionnaires. The response rate of completed questionnaires from email invitations was 32.9%. On multivariable analysis, life satisfaction and PoM were associated with age (b = 0.008 in both), better perceived health (b = 0.262 and 0.308, respectively), family interaction (b = 0.264 and 0.207, respectively), and friend relationships (b = 0.076 and 0.091, respectively). Being married (b = 0.191), being specialized (b = 0.127), working in private practice, and spending 10 to 39 h per week with patients (b = 0.101 to 0.162) were associated with a higher level of life satisfaction but not PoM. CONCLUSIONS: Specialists working in private practice without working overtime were associated with better life satisfaction. However, the dentists' health and relationships with family were more related to their subjective well-being than their professional achievements. CLINICAL RELEVANCE: Our findings can help policymakers increase awareness of the well-being of general dentists and those in academia or hospitals to promote their mental health.

Recombinant human platelet-derived growth factor improves root coverage of a collagen matrix for multiple adjacent gingival recessions: A triple-blinded, randomized, placebo-controlled trial.

AIM: To evaluate the efficacy of recombinant human platelet-derived growth factor (rhPDGF)-BB combined with a cross-linked collagen matrix (CCM) for the treatment of multiple adjacent gingival recession type 1 defects (MAGRs) in combination with the coronally advanced flap (CAF). MATERIALS AND METHODS: Thirty patients were enrolled in this triple-blind, randomized, placebo-controlled trial and treated with either CAF + CCM + rhPDGF, or CAF + CCM + saline. The primary outcome was mean root coverage (mRC) at 6 months. Complete root coverage, gain in gingival thickness (GT), keratinized tissue width, volumetric and ultrasonographic changes, and patient-reported outcome measures were also assessed. Mixed-modelling regression analyses were used for statistical comparisons. RESULTS: At 6 months, the mRC of the CCM + rhPDGF and CCM alone groups were 88.25% and 77.72%, respectively (p = .02). A significant gain in GT was consistently observed for both treatment arms, and more so for the patients receiving the matrix containing rhPDGF through time (0.51 vs. 0.80 mm, on average, p = .01). The rhPDGF + CCM treated patients presented greater volume gain, higher soft tissue thickness, and a superior aesthetic score. CONCLUSION: rhPDGF enhances the clinical, volumetric, and aesthetic outcomes of MAGRs above the results achieved with CAF + CCM alone (ClinicalTrials.gov NCT04462237).

Ultrasonographic tissue perfusion analysis at implant and palatal donor sites following soft tissue augmentation: A clinical pilot study.

AIM: To describe the application of power Doppler Ultrasonography (US) for evaluating blood flow at implant and palatal donor sites following soft tissue augmentation with the connective tissue graft (CTG). MATERIALS AND METHODS: Five patients exhibiting a peri-implant soft tissue dehiscence received treatment with a coronally advanced flap and corresponding CTG. Power Doppler US was used for assessing blood volume at baseline, 1 week, 1 month, 6 months and 12 months post-surgery for assessing blood-flow dynamics at the implant and palatal donor sites. The speed-weighted and power-weighted colour pixel density (CPPD) were computed from colour velocity (CV) and colour power (CP), respectively. RESULTS: A mean increase in CV of 199.25% was observed at the midfacial region of the implant sites after 1 week compared to baseline. CV and CP were increased in all sites at 1 week and 1 month. At 6 and 12 months, the mean CV appeared lower than baseline at the implant sites. CCPD was increased at the palatal donor sites and at the great palatine foramen areas at the 1-week and 1-month post-operative evaluations. CONCLUSIONS: Power Doppler US is a non-invasive and valuable tool for estimating tissue perfusion and CPPD variation during different phases of intra-oral soft tissue graft healing.

Maintenance visit regularity has a different impact on periodontitis-related tooth loss depending on patient staging and grading.

AIM: To assess whether maintenance variables have a differential effect on tooth loss due to periodontitis (TLP) based on staging and grading. MATERIALS AND METHODS: Patients treated for periodontitis for a minimum of ≥10 years follow-up were included and categorized according to their stage and grade at baseline. Impact of number, regularity, and pattern of supportive periodontal therapy visits (SPT) on TLP was explored by dividing teeth into test (5 year time periods prior to TLP events) and control groups (random 5 year periods without tooth loss). RESULTS: The regularity of maintenance visits, but not the overall quantity, had a significant impact on risk of TLP and showed higher importance as staging and grading increased (larger impact for stages III/IV and grade C). The minimum threshold of visits below which the risk of TLP was equivalent to that of the control group was one visit every 7.4 months for stages I-II, 6.7 months for stage III-IV, 7.2 months for grade B and 6.7 months for grade C. This frequency should be increased for former and current smokers, diabetics and elderly patients. Stage III and IV patients who skip more than 1 year of maintenance in a 5 year period have an increased risk of TLP (OR = 2.55) compared to those only miss 1 year. A similar trend was noted for grade C patients, but not for stages I/II or grades A/B. CONCLUSIONS: Lack of SPT regularity and missing multiple years of maintenance had a larger influence on risk of TLP for higher-level staging and grading.

Comprehensive peri-implant tissue evaluation with ultrasonography and cone-beam computed tomography: A pilot study.

OBJECTIVES: The aim of the present study was to explore the feasibility of ultrasonography (US) for clinical imaging of peri-implant tissues. MATERIAL AND METHODS: Patients with ≥1 implant, a cone-beam computed tomography (CBCT) scan, an US scan, and clinical photographs taken during the surgery were included. The crestal bone thickness (CBT) and facial bone level (FBL) were measured on both US and CBCT modalities, and direct FBL measurements were also made on clinical images. US measurements were compared with CBCT and direct readings. RESULTS: A total of eight implants from four patients were included. For FBL measurements, US and direct (r2 = 0.95) as well as US and CBCT (r2 = 0.85) were highly correlated, whereas CBCT correlated satisfactorily with the direct reading (r2 = 0.75). In one implant without facial bone, CBCT was not able to measure CBT and FBL accurately. The estimated bias for CBT readings was 0.17 ± 0.23 mm (p = .10) between US and CBCT. US blood flow imaging was successfully recorded and showed a wide dynamic range among patients with different degrees of clinical inflammation. CONCLUSION: US is a feasible method to evaluate peri-implant facial crestal bone dimensions. Additional US features, for example, functional blood flow imaging, may be useful to estimate the extent and severity of inflammation.

Intraoral scanning reduces procedure time and improves patient comfort in fixed prosthodontics and implant dentistry: a systematic review.

OBJECTIVES: The primary aim of this systematic review was to evaluate whether intraoral scanning (IOS) is able to reduce working time and improve patient-reported outcome measures (PROMs) compared to conventional impression (CI) techniques, taking into account the size of the scanned area. The secondary aim was to verify the effectiveness of IOS procedures based on available prosthodontic outcomes. MATERIALS AND METHODS: Electronic and manual literature searches were performed to collect evidence concerning the outcomes of IOS and CI performed during the treatment of partially and complete edentulous patients for tooth- or implant-supported restorations. Qualitative analysis was conducted to evaluate the time efficiency and PROMs produced by the two different techniques. Clinical prosthodontic outcomes were analyzed among the included studies when available. RESULTS: Seventeen studies (9 randomized controlled trials and 8 prospective clinical studies) were selected for qualitative synthesis. The 17 included studies provided data from 430 IOS and 370 CI performed in 437 patients. A total of 7 different IOS systems and their various updated versions were used for digital impressions. The results demonstrated that IOS was overall faster than CI independent of whether quadrant or complete-arch scanning was utilized, regardless of the nature of the restoration (tooth or implant supported). IOS was generally preferred over CI regardless of the size of the scanned area and nature of the restoration (tooth- or implant-supported). Similar prosthodontic outcomes were reported for workflows implementing CI and IOS. CONCLUSIONS: Within the limitations of this systematic review, IOS is faster than CI, independent of whether a quadrant or complete arch scan is conducted. IOS can improve the patient experience measured by overall preference and comfort and is able to provide reliable prosthodontic outcomes. CLINICAL RELEVANCE: Reduced procedure working time associated with the use of IOS can improve clinical efficiency and the patient experience during impression procedures. Patient-reported outcome measures (PROMs) are an essential component of evidence-based dental practice as they allow the evaluation of therapeutic modalities from the perspective of the patient. IOS is generally preferred by patients over conventional impressions.

Efficacy of microsurgery and comparison to macrosurgery for gingival recession treatment: a systematic review with meta-analysis.

OBJECTIVES: Microsurgical principles, techniques, and armamentarium have made significant contributions to the periodontal plastic surgery. The present meta-analysis aimed to investigate the overall efficacy of microsurgery on root coverage, and its clinical outcomes when compared to traditional macrosurgery. MATERIAL AND METHODS: Electronic searches on PubMed, Embase, and CINAHL were used to retrieve prospective clinical trials. Primary outcomes were the mean root coverage (mRC) and probability of achieving complete root coverage (cRC), with secondary outcomes as other periodontal parameters and patient-reported outcome measures (PROMs). RESULTS: Nineteen studies were included in the quantitative analysis. Microsurgery was estimated to achieve 83.3% mRC and 69.3% cRC. From a subgroup of 9 comparative studies, it was estimated microsurgery increased mRC by 6.6% (p<0.001) and cRC by 27.9% (p<0.01) compared to macrosurgical control treatments. Operating microscope (OM) yielded a significantly 6.7% higher mRC than the control group (p=0.002), while using loupes showed 6.16% increase in mRC with a borderline significance (p=0.09). OM and loupes-only had a 31.05% (p=0.001) and 25.54% (p=0.001) increases in achieving cRC compared to control, respectively. As for PROMs, microsurgery reduced postoperative pain (p<0.001) and enhanced esthetics (p= 0.05). CONCLUSIONS: Microsurgery significantly improved mean root coverage, probability of achieving complete root coverage, esthetics, and post-surgical recovery. Microsurgery enhances not only subclinical healing but also clinical outcomes, possibly owing to its minimally invasive approach and surgical precision. CLINICAL RELEVANCE: Periodontal plastic microsurgery is minimally invasive, inducing less surgical trauma and ultimately resulting in improved clinical outcomes, patient's satisfaction, and quality of life.

Potential of Using an Implant Fixture as a Ridge Expander for Minor Ridge Augmentation: An Ex Vivo Randomized Controlled Study.

To place implants with minimal trauma is what the patient and clinician are seeking. Hence, the aim of this study was to quantify the potential of using an implant fixture as a ridge expander in an underprepared osteotomy. Thirty-eight edentulous sites in 12 human cadaver jaws with ridge widths ranging from 4 to 6 mm and with type 3 or type 4 bone density were randomly assigned into 2 groups. In the ridge expansion group (RE), each osteotomy was drilled to a width of 2.8 mm and depth of 11.5 mm. In the non-ridge expansion (NE) control group, each osteotomy was drilled to a width of to 3.4 mm and depth of 11.5 mm. A 3.7 mm × 11.5 mm tapered implant was inserted into each site. The ridge width before (RW1) and after (RW2) implant placement as well as the buccal plate thickness (BPT) post-insertion were measured and analyzed. In the RE group, the average RW1 and RW2 were 4.69 ± 0.45 mm and 5.54 ± 0.35 mm, respectively, corresponding to a statistically significant ridge expansion of 0.85 mm (P < .01). In the NE group, no ridge width gain was observed (RW1: 4.79 ± 0.40 mm, RW2: 4.88 ± 0.42 mm). Compared to NE, RE resulted in a statistically greater BPT (1.08 ± 0.28 mm after RE vs 0.71 ± 0.37 mm after NE, P < .001). Our study determined that it was physically possible to widen a ridge by an average of 0.85 mm by osteotomy underprepation in ridge with type 3 or type 4 bone density, which effectively turned the implant upon insertion into a ridge expander. The physiological consequences of this method of ridge expansion in a living person must be established before drawing further conclusions about its clinical indications or efficacy.

Ultrasonographic characterization of lingual structures pertinent to oral, periodontal, and implant surgery.

OBJECTIVES: Increased applications of ridge augmentation in the lingual posterior mandible call for an urgent need to study its anatomy. Therefore, our first aim was to validate ultrasound in measuring the mandibular lingual structures in human cadavers. Secondarily, to test its feasibility in imaging the lingual nerve in live humans. MATERIALS AND METHODS: Nine fresh un-embalmed fully/partially edentulous cadaver heads were utilized for aim 1. Three areas in the lingual mandible were imaged (mandibular premolar, molar, and retromolar). Immediately after, biopsies were harvested from each site. The thickness of the mucosa, mylohyoid muscle, and lingual nerve diameter was measured via ultrasound and statistically compared to histology. Similarly, the lingual nerve in live humans was also imaged. RESULTS: None of the differences between the ultrasound and histology measurements reached statistical significance (p > .05). The mean mucosal thickness via ultrasound and histology was 1.45 ± 0.49 and 1.39 ± 0.50 mm, 5 mm lingual to the mylohyoid muscle attachment. At 10 mm beyond the attachment, the ultrasound and histologic values were 1.54 ± 0.48 and 1.37 ± 0.49, respectively. The mean muscle thickness measured via ultrasound and histology was 2.31 ± 0.56 and 2.25 ± 0.47 mm, at the 5 mm distance. At the 10 mm distance, the measurements were 2.46 ± 0.56 and 2.36 ± 0.5 mm, respectively. The mean ultrasonic lingual nerve diameter was 2.38 ± 0.44 mm, versus 2.43 ± 0.42 mm, with histology. The lingual nerve diameter on 19 live humans averaged to 2.01 ± 0.35 mm (1.4-3.1 mm). CONCLUSIONS: Within its limitations, ultrasound accurately measured mandibular lingual soft tissue structures on cadavers, and the lingual nerve on live humans.

Life satisfaction of Taiwanese dental graduates received residencies in the U.S.: a cross-sectional study.

BACKGROUND: Each year, more than 200 international dental graduates start U.S. specialty trainings to become specialists. It is unknown if their life satisfaction is associated with any dental career-related factor before residencies (e.g. dental school class rank, research experience, or private practice experience) and after residencies (e.g. staying in the U.S., teaching status, workplace, or board certification). This cross-sectional study aimed to identify these potential factors by surveying Taiwanese dental graduates who pursued U.S. residencies. METHODS: Life satisfaction was measured with a structured questionnaire, Satisfaction With Life Scale (SWLS), which includes five statements on a 5-point Likert scale. Online surveys were sent out to 290 Taiwanese dental graduates who were known to pursue U.S. residencies. T-test, one way analysis of variance, and multivariable adjusted generalized linear model (GLM) were used to assess the differences of mean SWLS scores from different variables. RESULTS: Surveys were completed by 158 dentists. Mean SWLS score of 125 specialists was higher (p = 0.0007) than the score of 33 residents. For the 125 specialists, multivariable adjusted GLM demonstrated better life satisfaction was positively associated with multiple independent factors, such as having research experience, being ranked in the top 26 ~ 50% of the class in dental school, starting U.S. residency within 4 years after dental school, starting residency before year 1996, and specializing in endodontics (vs. periodontics). Life satisfaction was not associated with any factors after residency (e.g. staying in the U.S. afterwards, teaching status, or workplace), but better mean life satisfaction score was significantly associated with being American specialty board certified (p < 0.001) for the specialists in the 26 ~ 75% of their class in dental school. For the 33 residents, better mean life satisfaction score was associated with better dental school class rank in both bivariate (p = 0.020) and multivariable adjusted GLM (p = 0.004) analyses. CONCLUSIONS: The life satisfaction of Taiwanese dental graduates pursuing U.S. residencies might be associated with some professional factors, such as research experience, dental school class rank, residency timing, specialty type, and specialty board certification. We hope our results may provide some objective information on making career decisions for international dental graduates/students who are preparing for U.S. residency.

A randomized controlled trial to compare aesthetic outcomes of immediately placed implants with and without immediate provisionalization.

INTRODUCTION: There are mixed results regarding the aesthetic advantage of immediate provisionalization of dental implants. Therefore, this study aimed to compare facial mucosal level of single immediately placed implants with and without immediate provisionalization. METHODS: Single implants were immediately placed to replace a hopeless maxillary anterior or premolar tooth in 40 subjects. Each implant was randomly assigned to receive a non-occluding temporary crown or a healing abutment after implant placement. At 4 months, these implants were permanently restored and followed up for 12 months. Clinical and radiographic parameters were measured and compared. RESULTS: The implant survival rate at 12 months in the test and control group was 90% and 100%, respectively. Mid-facial mucosal marginal level and papilla height changes were minimal within groups, and no significant differences were found between the two groups. The amount of marginal bone remodelling was modest, with no significant difference between the two groups. Radiographic bone changes were not statistically different between the groups, except for the vertical crestal bone resorption. CONCLUSION: Immediate implant placement with or without provisionalization can achieve stable vertical soft tissue level for 12 months as compared to pre-extraction level. However, immediate provisionalization was not able to improve the aesthetic outcome further.

Microscope and micro-camera assessment of Schneiderian membrane perforation via transcrestal sinus floor elevation: A randomized ex vivo study.

OBJECTIVE: We sought to assess the effectiveness of using a microscope and non-invasive camera for assessing sinus membrane perforations during transcrestal sinus floor elevation (TSFE). MATERIALS AND METHODS: Five fresh human cadaver heads corresponding to eight maxillary sinuses (six bilateral and two unilateral) underwent 4 TSFEs per sinus (a total of 32 single site elevations). Each elevation was randomly assigned to receive a three or six mm membrane elevation height (MEH). A microscope and micro-camera were used to assess the sinus membrane perforation. Afterwards, radiological and clinical membrane perforation assessments were performed. The statistical analysis results are expressed using the means, standard deviations, range values of the residual ridge height (RRH), residual ridge width (RRW), sinus membrane thickness (SMT) and incidence of perforation (IoP). Generalized linear methods were used to test for the correlation of RRH and MEH to the microscope and micro-camera perforation assessments and the correlation of microscope and micro-camera assessments with the post-operative CBCT and crestal liquid evaluation. RESULTS: The cumulative percentage of IoP was 40.62%, (23.07% with 3 mm MEH, and 76.92% with 6 mm MEH, p < 0.05). The perforation assessed using either the microscope or micro-camera coincided with the post-operative CBCT and crestal liquid assessment in 87.55% sites. No significant correlation was found between the microscope or micro-camera assessments with RRH or MEH. CONCLUSION: Application of a microscope and micro-camera during transcrestal sinus floor elevation may allow the detection of the integrity of the Schneiderian membrane with greater than 85% accuracy in this ex vivo model.

Schneiderian membrane perforation via transcrestal sinus floor elevation: A randomized ex vivo study with endoscopic validation.

OBJECTIVE: To endoscopically determine the incidence of Schneiderian membrane perforation during transcrestal maxillary sinus floor elevation (SFE), in relation to the bone preparation technique, amount of bone graft, membrane elevation height and different surgical steps. MATERIALS AND METHODS: Seven cadaver heads corresponding to 12 maxillary sinuses were used to perform three SFE via transcrestal approach per sinus (36 elevations). Each sinus was randomly assigned to either the Sinus Crestal Approach (SCA) drill kit technique (experimental group) or the conventional osteotome technique (control group). During all phases of the surgery, the integrity of the sinus membrane was monitored through endoscopic examination. RESULTS: A significant difference was found in the incidence of perforation (p = 0.007) and vertical elevation height (p < 0.001) between the study groups, favoring the experimental group. A safety elevation threshold of 5 mm without bone graft and implant placement was estimated. A significant correlation was observed between the residual ridge height and the incidence of perforation (p < 0.001; OR = 0.51). CONCLUSION: The SCA drill kit may demonstrate superior osteotomy preparation and membrane elevation capabilities to the osteotome technique, and significantly when a 6-mm SFE is indicated. Residual ridge height and vertical elevation height are risk determinant factors.

Ultrasonography for noninvasive and real-time evaluation of peri-implant tissue dimensions.

AIM: Existing methods for evaluating marginal bone loss and tissue biotype around dental implants present with many limitations. The aim of this study was to examine the accuracy of high-resolution, 3-dimensional ultrasound to measure peri-implant tissue dimensions. MATERIAL AND METHODS: A 25-MHz ultrasound probe prototype was used to scan peri-implant tissues of 17 implants from seven fresh human cadavers. Four ultrasonic measurements were made as follows: the marginal bone level/thickness, and mucosal level/thickness. The readings were statistically compared to cone beam computed tomography (CBCT) and/or open bone measurements. RESULTS: The correlations (r) between the ultrasound and direct/CBCT readings of the four parameters ranged from 0.85 to 0.98 (p < 0.0001). The mean absolute difference in the four parameters between ultrasound-direct and ultrasound-CBCT ranged from 0.033 to 0.24 mm. CONCLUSION: Encouraging evidence is shown that ultrasound can accurately measure peri-implant tissue dimensions. Following clinical trial validations, ultrasound offers potential as a valuable tool to evaluate long-term peri-implant tissue stability without concerns of ionizing radiation and image artefacts around implants.

Association of Inflammatory Status and Maxillary Sinus Schneiderian Membrane Thickness.

OBJECTIVES: Certain Schneiderian membrane thicknesses (SMT) have shown to be more prone to tearing/perforation, and some pathologies might influence SMT. Henceforth, we aimed at studying the correlation of inflammatory status to SMT in human fresh cadaver heads. MATERIAL AND METHODS: A total of 14 fresh cadaver heads including 27 Schneiderian membrane specimens were histologically collected. A 10-item inflammatory score was determined in the entire sample and also in the thinner and thicker areas of each sample. Data was analyzed by using the Wilcoxon rank test and the Spearman's rank correlation. RESULTS: The mean measured SMT was 0.40 ± 0.12 mm and the median was 0.33 ± 0.12 mm. A weak positive correlation was found between the mean SMT and inflammation score without a statistical significance. (r = 0.385, p = 0.115). The Wilcoxon signed-rank test showed a statistical difference between the medians of the thinner and thicker areas (p < 0.001). The mean inflammation score of the thinner and thicker areas was 8.55 ± 2.57 and 11.61 ± 2.65, respectively. A moderate positive and statistically significant correlation was found between the inflammation score and the thickness of the thinner and thicker areas (r = 0.638, p = 0.000). CONCLUSION: A moderate association between the Schneiderian membrane thickness and the level of inflammation exists.

The Association Between Buccal Mucosa Thickness and Periimplant Bone Loss and Attachment Loss: A Cross-Sectional Study.

PURPOSE: The aim of this study was to assess if there is an association between buccal mucosa thickness and periimplant attachment loss after 1 year of function. MATERIALS AND METHODS: A total of 28 patients (14 periimplantitis implants and 14 healthy implants) were included. The buccal mucosal thickness was assessed using K-files at 3 mm apical to the soft tissue margin of the implant. Probing depth, recession (REC), clinical attachment level (CAL), bleeding on probing, and radiographic bone loss on mesial and distal sites of the implant were recorded. RESULTS: The data showed that there was a statistically significant difference in midfacial REC between thin and thick buccal mucosa groups. However, the CAL was not statistically significant different between both groups. In addition, there was no statistically significant difference in mesial and distal bone loss between implants with thin and thick mucosa. CONCLUSION: When the midfacial soft tissue thickness was thin, the midfacial REC was greater and the CAL also tended to be higher. There was no association between buccal mucosa thickness and periimplant bone loss on mesial and distal sites of the implant after 1 year of function.