Nicola Pranno

Early peri-implant bone loss: a prospective cohort study

The aim of this study was to measure the early peri-implant bone level changes before the completion of an implant-abutment connection and to evaluate the influence of demographic, biologically relevant, anatomical, and implant-specific variables on these changes. A prospective cohort study design was used. STROBE guidelines were followed. The sample comprised 493 implants placed using a two-stage surgical procedure. Random allocation was used to determine the implant placement depth. Peri-apical radiographs taken at implant insertion and at the second surgery 2 months later were matched. Kappa statistics were used to compute intra- and inter-examiner reliability. The statistical analysis was performed at the implant level. Two-way analysis of variance (ANOVA) with the Bonferroni adjusted post hoc test was used to evaluate the influence of variables. One-way ANOVA with Tukeys range test and unpaired Student t-tests were used to analyze significant variables. Early marginal bone remodelling was -0.86 mm. The timing of implant placement (P=0.00) and the depth of implant placement (P≤0.05) significantly influenced early bone remodelling. Relevant radiographic early bone loss was found, but implants initially positioned below the alveolar crest and inserted ≥3 months after tooth extraction showed statistically significant higher marginal bone loss during the healing phase.

The Role of 3 Tesla Diffusion-Weighted Imaging in the Differential Diagnosis of Benign versus Malignant Cervical Lymph Nodes in Patients with Head and Neck Squamous Cell Carcinoma

Objective. The aim of this study was to validate the role of diffusion-weighted imaging (DWI) at 3 Tesla in the differential diagnosis between benign and malignant laterocervical lymph nodes in patients with head and neck squamous cell carcinoma (HNSCC). Materials and Methods. Before undergoing surgery, 80 patients, with biopsy proven HNSCC, underwent a magnetic resonance exam. Sensitivity (Se) and specificity (Spe) of conventional criteria and DWI in detecting laterocervical lymph node metastases were calculated. Histological results from neck dissection were used as standard of reference. Results. In the 239 histologically proven metastatic lymphadenopathies, the mean apparent diffusion coefficient (ADC) value was 0.903 × 10−3 mm2/sec. In the 412 pathologically confirmed benign lymph nodes, an average ADC value of 1.650 × 10−3 mm2/sec was found. For differentiating between benign versus metastatic lymph nodes, DWI showed Se of 97% and Spe of 93%, whereas morphological criteria displayed Se of 61% and Spe of 98%. DWI showed an area under the ROC curve (AUC) of 0.964, while morphological criteria displayed an AUC of 0.715. Conclusions. In a DWI negative neck for malignant lymph nodes, the planned dissection could be converted to a wait-and-scan policy, whereas DWI positive neck would support the decision to perform a neck dissection.

Survival Analysis of Implant in Patients With Diabetes Mellitus: A Systematic Review.

Aim:To determine the survival trend of dental implants after functional loading for ≥1 year in diabetic patients. Material and Methods:An electronic search of the Cochrane Oral Health Groups Trials Register, Medline and Embase, plus a manual search up to December 2015 was performed. Studies assessing the survival rate of dental implants in patients with a diagnosis of diabetes mellitus were considered eligible. Screening of studies, quality assessment, and data extraction were conducted independently by 2 reviewers. Life-table analysis and Kaplan–Meier survival curves were used to evaluate implant survival and to plot the cumulative survival rate and cumulative hazard ratio. Results:Seven studies, including 1142 implants were identified. The cumulative survival rate was 0.96 ± 0.10 before loading, 0.93 ± 0.10 and 0.91 ± 0.10 at 1 year, and at the end of the follow-up period, respectively. The hazard ratio was 4% during the period of osseointegration, 3% during the first year of loading, and remained constant over the 6-year follow-up. Conclusions:Patients with diabetes mellitus showed an increasing trend of implant failure during the period of osseointegration and the first year of loading.

3.0 Tesla MRI in the early evaluation of inferior alveolar nerve neurological complications after mandibular third molar extraction: a prospective study

OBJECTIVES To evaluate the use of 3.0 T MRI in the prognosis of inferior alveolar nerve (IAN) sensory disorders after mandibular third molar extraction, in the early post-operative period. METHODS 343 IANs were examined before and 3 days after surgery. Two radiologists evaluated the course of the nerve and the relative signal intensity (RSI). Cohens kappa coefficient (κ) and intraclass correlation coefficient (ICC) were used to evaluate the interobserver (k = 0.891) and intra-observer variability (ICC = 0.927; 0.914, respectively). The IANs were divided into four groups on the basis of neurosensory disorders recovery time. ANOVA was used to evaluate the differences among the RSIs of the four groups, and multiple comparisons were performed with Tukeys range test. RESULTS No differences in the course of IANs were found before and after surgery. In 280 IANs, no iatrogenic paraesthesia was found (Group A). 63 IANs showed a neurosensory impairment. 38 IANs showed recovery of post-operative paraesthesia at 3-month follow-up (Group B). 16 IANs showed a full recovery of iatrogenic paraesthesia at 6-month follow-up (Group C). Seven IANs displayed a full recovery at 12-month follow-up and two IANs showed persistence of neurosensory disorders at 18-month follow-up (Group D). The one-way ANOVA results indicated statistically significant difference among all groups (p < 0.05), except between Groups C and D (p = 0.504). CONCLUSIONS The early evaluation of RSI values represents a valid tool to determine the prognosis of IAN sensory disorders after mandibular third molar extraction.

Comparing proton density and turbo spin echo T2 weighted static sequences with dynamic half-Fourier single-shot TSE pulse sequence at 3.0 T in diagnosis of temporomandibular joint disorders: a prospective study.

OBJECTIVES The aim of this prospective study was to compare dynamic and static sequences in the evaluation of temporomandibular joint disorders using a 3.0 -T imaging unit. METHODS 194 patients were evaluated by static (double echo proton density weighted/turbo spin echo T2 weighted sequences) and dynamic (half-Fourier single-shot turbo spin echo sequences)imaging. Two radiologists evaluated in consensus the quality of images, the disc position and morphological alterations. The Kendall rank correlation coefficient (τ-b) was used to compare the qualitative rating between static and dynamic sequences. Cohens kappa coefficient (k) was used to assess the agreement of disc position and morphological alterations between both sequences. The intraclass correlation coefficient was used to calculate the intraobserver variability. The significance was set at p ≤ 0.05. RESULTS The correlation between both sequences in the qualitative evaluation was τ-b = 0.632. The agreement between both techniques in the evaluation of disc position was k = 0.856. The agreement between both techniques in assessing the morphological alterations was k = 0.487. In the static sequences, the intraclass correlation coefficient was 0.915 in the qualitative evaluation, 0.873 in the evaluation of disc position and 0.934 in the assessment of morphological alterations. In the dynamic sequences, the intraclass correlation coefficient was 0.785 in the qualitative evaluation, 0.935 in the evaluation of disc position and 0.826 in the assessment of morphological alterations. CONCLUSIONS Static imaging remains the gold standard in the evaluation of the temporomandibular joint. Dynamic imaging is a valuable tool that can provide additional information about topographic changes in the disc-condyle relationship.

Performance of Mesenchymal Cell-Scaffold Constructs in Human Oral Reconstructive Surgery: A Systematic Review

Background: Different sources of cultured cells combined with different scaffolds (allogenic, xenogeneic, alloplastic or composite materials) have been tested extensively in vitro and in preclinical animal studies, but there have been only a few clinical trials involving humans. Aim: This study reviewed all of the English language literature published between January 1990 and December 2015 to assess the histological performance of different mesenchymal cell-scaffold constructs used for bone regeneration in human oral reconstructive procedures. Methods: An electronic search of the MEDLINE and Cochrane Central Register of Controlled Trials databases complemented by manual searching was conducted to identify studies involving histological evaluation of mesenchymal cell-scaffold constructs in human oral surgical procedures. The methodological quality of randomized controlled clinical trials and controlled clinical trials was assessed using the Cochrane Collaboration tool for assessing the risk of bias. Heterogeneity was assessed using Review Manager software. Considering the heterogeneity, the data collected were reported by descriptive methods and a meta-analysis was applied only to the articles that reported the same outcome measures. The articles were classified and described based on the material scaffolds used. Results: The search identified 1030 titles and 287 abstracts. Full-text analysis was performed for 32 articles, revealing 14 studies that fulfilled the inclusion criteria. Three randomized controlled clinical trials were identified as potentially eligible for inclusion in a meta-analysis. The studies were grouped according to the scaffold materials used: bone allograft (three studies), polyglycolic-polylactic scaffold (four studies), collagen sponge (two studies), and bovine bone matrix (five studies). The stem cells used in these studies had been sourced from the iliac crest, periosteum, dental pulp and intraoral sites. Conclusions: The very small amount of available data makes it impossible to draw any firm conclusions regarding the increase in bone formation in human oral reconstructive procedures when using graft materials engineered with autogenous stem cells.

Comparative Histological and Histomorphometric Results of Six Biomaterials Used in Two-Stage Maxillary Sinus Augmentation Model after 6-Month Healing

Objectives To evaluate the performances of six different bone substitute materials used as graft in maxillary sinus augmentation by means of histological and histomorphometric analysis of bone biopsies retrieved from human subjects after a 6-month healing period. Materials and Methods Six consecutive patients (3 males, 3 females, aged 50-72 years), healthy, nonsmokers, and with good oral hygiene, presenting edentulous posterior maxilla with a residual bone crest measuring ≤ 4 mm in vertical height and 3 to 5 mm in horizontal thickness at radiographic examination, were selected to receive sinus augmentation and delayed implant placement. Under randomized conditions, sinus augmentation procedures were carried out using mineralized solvent-dehydrated bone allograft (MCBA), freeze-dried mineralized bone allograft (FDBA), anorganic bovine bone (ABB), equine-derived bone (EB), synthetic micro-macroporous biphasic calcium-phosphate block consisting of 70% beta-tricalcium phosphate and 30% hydroxyapatite (HA-β-TCP 30/70), or bioapatite-collagen (BC). After 6 months, bone core biopsies were retrieved and 13 implants were placed. Bone samples were processed for histological and histomorphometric analysis. CT scans were taken before and after surgery. After 4 months of healing, patients were restored with a provisional fixed acrylic resin prosthesis, as well as after further 2-4 months with a definitive cemented zirconia or porcelain-fused-to-metal crowns. Results There were no postoperative complications or implant failures. The histological examination showed that all biomaterials were in close contact with newly formed bone, surrounding the graft granules with a bridge-like network. No signs of acute inflammation were observed. The histomorphometry revealed 20.1% newly formed bone for MCBA, 32.1% for FDBA, 16.1% for ABB, 22.8% for EB, 20.3% for HA-β-TCP 30/70, and 21.4% for BC. Conclusions Within the limitations of the present investigation, all the six tested biomaterials showed good biocompatibility and osteoconductive properties when used in sinus augmentation procedures, although the FDBA seemed to have a better histomorphometric result in terms of newly formed bone and residual graft material. This trial is registered with ClinicalTrials.gov Identifier (Registration Number): NCT03496688.

Efficacy of preoperative administration of paracetamol-codeine on pain following impacted mandibular third molar surgery: A randomized, split-mouth, placebo-controlled, double-blind clinical trial

Objectives. The aim of this study was to determine the effectiveness of preoperative administration of single-dose of paracetamol-codeine, in the relieving of acute postoperative pain after the surgical removal of an impacted mandibular third molar. Materials and Methods. The study cohort consisted of 32 Caucasian outpatients, giving a total of 64 bilateral symmetrical impacted mandibles. Patients were randomized in two experimental groups to receive a preoperative oral dose of paracetamol-codeine (analgesic group) or a placebo (placebo group) at the first and second surgeries. Study participants were asked to record pain intensity scores during the operation and the next 2 days, the time of the first request for rescue analgesic, and the total number of postoperative-supplement paracetamol-codeine tablets. Results. The pain intensity score on the first day was significantly lower in the analgesic group than in the placebo group (p < 0.001). The time to using rescue therapy was significantly longer in the analgesic group than in the placebo group (p = 0.004). The number of paracetamol-codeine tablets used postoperatively did not differ between the analgesic and placebo groups (p = 0.104). Conclusions. Preoperative paracetamol-codeine is effective in providing immediate postoperative pain control after third molar surgery and in delaying the initial onset of pain. This trial is registered with ClinicalTrials.gov Identifier (Registration Number): NCT03049878.

The effects of a common stainless steel orthodontic bracket on the diagnostic quality of cranial and cervical 3T- MR images: A prospective, case-control study

OBJECTIVES To evaluate the effect of orthodontic stainless steel brackets and two different types of archwires on the diagnostic quality of 3-T MR images. METHODS This prospective, case-control study was conducted following Strengthening the Reporting of Observational Studies in Epidemiology guidelines. The recruitment was conducted among orthodontic patients. 80 subjects, requiring MRI for the presence of temporomandibular disorders, were enrolled and divided into four groups: 20 patients using aligners (control group); 20 patients with stainless steel brackets without archwires; 20 patients with stainless steel brackets and nickel-titanium archwires; and 20 patients with stainless steel brackets and stainless steel archwires. Two experts in neuroradiology evaluated the images to determine the amount of distortion in 6 regions and 48 districts. A score was subjectively assigned according to a modified receiver operating characteristic method of distortion classification. Any disagreement was resolved through consensus seeking; when this was not possible, a third neuroradiologist was consulted. The following statistical methods were used: descriptive statistics, Cohens kappa coefficient (k), Kruskal-Wallis test, pairwise comparisons using the Dunn-Bonferroni approach. The significance was set at p ≤ 0.05. RESULTS The presence of stainless steel brackets with or without archwires negatively influenced MRI of the cervical region, paranasal sinuses, head and neck region, and cervical vertebrae but did not influence MRI of brain and temporomandibular joint regions. CONCLUSIONS Patients with a stainless steel multibracket orthodontic appliance should remove it before cervical vertebrae, cervical region, paranasal sinuses, and head and neck MRI scans. The brain and temporomandibular joint region MRI should not require the removal of such appliances.