Vittorio Checchi

Radiographic analysis of a transalveolar sinus-lift technique: a multipractice retrospective study with a mean follow-up of 5 years.

BACKGROUND Various sinus-lift techniques have been described in the literature. The aim of this retrospective study is to evaluate the efficacy of a transalveolar sinus-lift technique in terms of implant survival, marginal bone loss, and complications. METHODS A total of 538 patient records were examined, and after applying exclusion and inclusion criteria, a sample of patients was included with a mean follow-up of 5 years. Implants with a smooth or tapered surface were considered. Therefore, only sinus lifts with inorganic bovine bone matrix or demineralized bone matrix were included, and 1,536 periapical radiographs were analyzed. Outcome measures were implant success, implant failure (peri-implantitis and loss of osseointegration), marginal bone resorption, and biologic complications (membrane perforations, sinusitis, and intraoperative and/or postoperative hemorrhage). Periapical radiographs were evaluated before surgery, post-surgery, and after 6 months and 1, 3, and 5 years. We analyzed the residual crestal bone height under the sinus, the amount (mm) of height increase after surgery, and values of implant marginal bone resorption for considered follow-ups. RESULTS Two hundred eighty-two (282) patients were excluded. Therefore, 256 patients treated with the transalveolar sinus-lift technique were included. A total of 376 dental implants and 323 sinus lifts were analyzed. The overall rates of implant success and failure were 94.9% and 5.1%, respectively. The mean bone loss around implants was 1.98 mm (mean follow-up of 5 years). Patients treated with inorganic bovine bone matrix showed a better implant success rate (P = 0.03) than did patients treated with demineralized human matrix. Three Schneiderian membrane perforations occurred in the 323 sinus lifts. In these cases, the surgeon performed another surgical operation after 3 months. Postoperative complications were peri-implantitis (six cases) and osseointegration losses (13 cases). CONCLUSIONS The transalveolar sinus-lift technique was a safe, minimally invasive technique with an implant success rate comparable to traditional implantology. The implant success rate was positively affected by the low-resorption graft material, and a low bone-resorption rate around implants was found.

Variables Affecting the Gingival Embrasure Space in Aesthetically Important Regions: Differences between Central and Lateral Papillae

This study evaluated different variables to determine their role in the appearance of the central and lateral upper jaw papillae. 292 interdental embrasures were examined. Personal variables were: age, smoke, and use of interproximal hygiene devices. The clinical characteristics were: tooth shape, periodontal biotype and papilla appearance. Radiographic measurements were: root to root distance at the cemento-enamel junction (horizontal distance), and bone crest to interdental contact point distance (vertical distance). The papilla recession increased with patient age. The horizontal distance of the central papilla was always greater (up to 1 mm) than that of the other papillae. The vertical distance of the central papilla was greater (up to 2 mm) than that of the other papillae for each class except for the normal one (Nordland & Tarnow classification). For vertical distances ≤5 mm, papillae were almost always present; for distances up to 6 mm, the lateral papillae belonging to the normal class disappeared, while the central papilla remained in 11% of cases; central papillae of class 1 were present in larger proportions until a vertical distance of 8 mm. The present observational study shows that differences on clinical and radiographic determinants do exist between central and lateral papillae. This variance should be strictly taken in account for a harmonious and stable treatment outcome on this highly aesthetic area.

Soft Tissue Response to Titanium Abutments with Different Surface Treatment: Preliminary Histologic Report of a Randomized Controlled Trial

The aim of this preliminary prospective RCT was to histologically evaluate peri-implant soft tissues around titanium abutments treated using different cleaning methods. Sixteen patients were randomized into three groups: laboratory customized abutments underwent Plasma of Argon treatment (Plasma Group), laboratory customized abutments underwent cleaning by steam (Steam Group), and abutments were used as they came from industry (Control Group). Seven days after the second surgery, soft tissues around abutments were harvested. Samples were histologically analyzed. Soft tissues surrounding Plasma Group abutments predominantly showed diffuse chronic infiltrate, almost no acute infiltrate, with presence of few polymorphonuclear neutrophil granulocytes, and a diffuse presence of collagenization bands. Similarly, in Steam Group, the histological analysis showed a high variability of inflammatory expression factors. Tissues harvested from Control Group showed presence of few neutrophil granulocytes, moderate presence of lymphocytes, and diffuse collagenization bands in some sections, while they showed absence of acute infiltrate in 40% of sections. However, no statistical difference was found among the tested groups for each parameter (p > 0.05). Within the limit of the present study, results showed no statistically significant difference concerning inflammation and healing tendency between test and control groups.

The Use of a Disclosing Agent During Resective Periodontal Surgery for Improved Removal of Biofilm

A total removal of the bacterial deposits is one of the main challenges of periodontal therapy. A surgical approach is sometimes required in order to allow a correct access to the areas not thoroughly reached during the initial therapy. The present study focuses on the surgical scaling effectiveness in root deposits removal; the potential support of a disclosing agent during this procedure is also evaluated. Forty surgical periodontal patients were randomly divided between surgeries where the operator was informed about a final examination of the residual root deposits and surgeries where the operator was not informed. Straight after scaling procedures a supervisor recorded the O’Leary Plaque Index of the exposed roots by mean of a disclosing agent and the percentage of teeth with residual biofilm. After the stained deposits removal, a second chromatic examination was performed and new data were collected. Mann-Whitney U-test and Wilcoxon test for paired samples were used for comparisons respectively between the two surgery groups and the first and the second chromatic examination; one-sided p-value was set at 0.05. At first examination no significant differences between the two groups were observed regarding Plaque Index (p=0.24) and percentages of teeth with residual biofilm (p=0.07). The 100% removal of roots deposits was never achieved during the study but a significant reduction of 80% of root deposits was observed between first and second examination (p=0.0001). Since root deposits removal during periodontal surgery resulted always suboptimal, the use of a disclosing agent during this procedure could be a useful and practical aid.

How Stable is Dentin As a Substrate for Bonding

Purpose of ReviewThis paper reviews the complexity of the composition of dentin, and the repercussions of this composition on the stability of dentin over time, particularly in relation to adhesive dental procedures.Recent FindingsDentin is a complex and dynamic structure that comprises the major part of the tooth. Most adhesive procedures in dentistry involve bonding to dentin. The hybrid layer (HL) created on the very variable and dynamic organic dentin phase may fail over time, leading to the failure of dental restorations. Literature showed that the collagen fibers in the HL are prone to hydrolysis and mechanical strain, as well as endogenous proteolytic activity (collagenolytic activity of matrix metalloproteinases and cysteine cathepsins). Hydrolysis of the resin phase of the HL also occurs over time.SummaryAdvancements in the area of dental adhesion have been huge. Silencing of collagenolytic enzymes (protease inhibitors and cross-linking agents) is one of the main strategies to decrease the degradation of the HL. In the following years, new techniques will also probably be available, and efficacy of some of the available techniques will perhaps be further clarified.

Evaluation of Clinical Effectiveness and Subjective Satisfaction of a New Toothbrush for Postsurgical Hygiene Care: A Randomized Split-Mouth Double-Blind Clinical Trial

The aim of this RCT was to evaluate plaque control and gingival health promotion effectiveness of a new toothbrush with extra-soft filaments in postsurgical sets. Ten consecutive patients with at least two scheduled symmetrical periodontal surgeries were selected. Following the first periodontal surgery, a test (TB1) or control (TB2) toothbrush was randomly assigned. After the second surgery, the remaining toothbrush was given. Patients were asked to gently wipe the surgical area from days 3 to 7 postoperatively and to gently brush using a roll technique from day 7 till the end of the study. Baseline evaluation took place on the day of surgery and follow-ups were performed at days 7, 14, and 30 postoperatively. A more evident PI reduction was recorded for test toothbrush where a regular decrease was observed till day 14; then, this parameter tended to stabilize, remaining however lower than that recorded for the control toothbrush. There were no statistical differences in the GI between test and control toothbrushes. All patients introduced the test toothbrush at surgical site at third day; the control toothbrush was introduced within a mean of 9 days. The introduction of the test toothbrush 3 days after periodontal surgery may be recommended.

Microbiological Response to Periodontal Therapy: A Retrospective Study

Background: Periodontitis is a multifactorial infection caused by a complex of pathogenic bacterial species that induce the destruction of periodontal structures. Objective: The aim of this study is to evaluate the presence and bacterial load of six periodontal pathogens bacteria, measured at initial visit and after osseous surgery in patients affected by chronic periodontitis and treated between 2005 and 2007. Methods: This cohort study was carried out on a sample of 38 consecutive patients affected by severe chronic periodontitis, diagnosed at baseline on the basis of probing depths equal to 6.68 ± 1.47 mm. On each subject, a microbiological test was performed before periodontal initial therapy and after osseous surgery (one year later). Five compromised teeth were chosen for each patient (the same teeth, before and after surgery), for a total of 190 teeth. Real-time PCR based analysis computed total bacterial load of the samples and quantified six periodontal pathogens: Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, Fusobacterium nucleatum and Prevotella intermedia. Data collection was made consulting medical charts. Results: Pocket probing depth reduction after surgery was 4.50 ± 1.54 mm (p=0.0001). The mean number of sites with bleeding at baseline was 2.08 ± 1.17 and 0.58 ± 1.00 after surgery (p=0.001). The mean number of sites with suppuration at baseline was 0.26 ± 0.86 and 0 after surgery (p=0.02). Cell count of each pathogen and total cell count were significantly higher at baseline than after surgery. Almost all bacteria presented a mean percentage reduction equal to that of the total count, except for Aa and Pi, which seemed to show a greater resistance. The difference of bacterial load, both before and after surgery, between smokers and non-smokers was not statistically significant (p<0.05). A statistically significant correlation was detected between pocket probing depth variation and bleeding on probing variation before and after the surgery, controlling for age (r=0.6, p=0.001). No significant correlations were observed between pocket probing depth and bacterial loads, except for Pg (r=0.5, p=0.001), Tf (r=0.6, p=0.001) and Td (r=0.4, p=0.02). Conclusions: Reduction of presence and bacterial load of the examined periodontal pathogens bacteria after osseous surgery, along with periodontal pocket reduction, appeared to be essential to achieve and maintain periodontal stability over years.

A New Transalveolar Sinus Lift Procedure for Single Implant Placement: The Ebanist Technique. A Technical Description and Case Series

Background: Nowadays, there are many techniques to compensate bone atrophies of the posterior maxilla in order to obtain an implant-supported rehabilitation. Objective: This case series describes the Ebanist technique: a sinus lift procedure to be used in case of extremely resorbed bone crests (≤3 mm) allowing simultaneous implant placement. Methods: With a dedicated cylindrical trephine bur, it is possible to harvest a cylinder of bone from a fresh mineralized frozen homologous bone block graft and to simultaneously create a trapdoor on the recipient site. The trapdoor cortical bone is detached from the sinus membrane and removed. Dental implant is placed into the graft before the grafting procedure since the cylindrical block, once inserted in the recipient area, is not able to oppose sufficient resistance to the torque needed for implant placement. Results: Second-stage surgery and following prosthetic rehabilitation were performed after 5 months. In all cases, implant stability was manually checked and no pathological symptoms or signs were recovered at any follow-up visit. Conclusion: This technique can be considered a valid procedure for implant therapy on atrophic posterior upper maxillae, when the residual bone crest is extremely resorbed.

Reconstruction of Atrophied Posterior Mandible with an Inlay Technique and Allograft Block: Technical Description and Histologic Case Reports

This paper presents a technical description of the inlay technique performed with an allograft block in the reconstruction of a severely atrophic posterior mandible. It includes a histologic case series of five patients treated with the same grafting procedure and rehabilitated with dental implants 2 months after placement of the graft. The histologic analysis showed large amounts of newly formed bone in tight connection with the allograft and large marrow spaces with intense cellular activity and the presence of osteocytes. Allografts might serve as an alternative to autogenous and heterologous grafting in posterior mandible augmentation using the inlay technique.

Safe New Approach to the Lingual Flap Management in Mandibular Augmentation Procedures: The Digitoclastic Technique

Purpose: This article describes the digitoclastic technique, an innovative procedure for coronal displacement of the lingual flap. The new technique has the potential to obtain primary flap closure without surgical risks to the anatomical structures on the lingual side of the mandible. Materials and Methods: Reconstruction of an atrophic mandible with guided tissue regeneration (guided bone regeneration) and implant placement is described, using the digitoclastic technique to displace the lingual flap coronally. Results: Coronal flap displacement was sufficient to obtain complete passive coverage of the grafted area. No bleeding or neurosensory complications were recorded, and no membrane exposure occurred. Conclusions: The digitoclastic technique reduces the risk of damage to the lingual nerve and minimizes the amount of bleeding during surgery, allowing progressive and controlled retraction of the flap until the desired detachment is achieved.