Critical investigation of the pre-surgical anatomic factors that influence the aesthetic result in post-extractive implantology and immediate prosthetic.

The aesthetic goals of implant dentistry should be similar to those of conventional prostheses. In implant-prosthetic rehabilitations of the anterior sectors, the quantity and quality of hard and soft tissue play a fundamental role in achieving the desired aesthetics and in integrating the restoration in a complete and harmonious way into the existing anterior dentition. Post-extraction implantology is a treatment option for implant therapy after the extraction of a single tooth in the anterior jaw. This article presents some key factors to analyze and follow in order to achieve a predictable and acceptable aesthetic result. The creation of a predictable peri-implant aesthetics requires adequate preservation of the bone and soft tissues around the teeth that will be extracted and a correct positioning of the 3D implant. Furthermore, aesthetic success requires the creation of a correct transmucosal path, during the provisional prosthetic phases, which must be replicated and maintained with the definitive crowns.

Guided sinus lift: virtual planning of surgical templates for lateral access.

The sinus lift with lateral approach is a regenerative technique nowadays considered predictable to increase the height of bone in the atrophic posterior maxilla. Knowledge of sinus anatomy and evaluation of risk factors are the basis of regenerative and rehabilitative surgical success. The positioning and size of the lateral antrostomy represent critical factors in the execution of regenerative surgery, due to the difficulty in transferring radiological information to the lateral wall of the maxillary sinus even for skilled surgeons. The knowhow of guided implant surgery in recent years is also finding use in planning and precisely delineating the lateral access to the maxillary sinus using CBCT imaging and dimensional reconstruction software, through the realization of surgical guides with 3D printing, as shown in the presented case.

Endodontic retreatment and bioceramics: A case report.

The success rate in endodontic retreatment can be significantly boosted by using materials that guarantee both intimate adhesion to the canal walls and long-term stability. Bioceramic cements used in root filling show interesting properties including extraordinary sealing capacities, antimicrobial activity that stimulates periapical healing and the continuous production of hydroxyopathitis for a long time. This case report deals with the application of bioceramic cement in endodontic retreatment. The Bioroot RCS (Septodont), thanks to its ability to firmly adhere both to the gutta-percha and to the walls of the canal and to definitively seal the apical third, can allow to obtain extraordinary healing in a relatively short time by exploiting its antimicrobial abilities. However, further studies are needed to assess the effectiveness of this technique over the long term.

Computer-guided implant surgery: analysis of dynamic navigation systems and digital accuracy.

After the static computer-guided implant surgery, borns the concept of "navigated implantology" (NI) that offers significant advantages in the treatment planning and help clinicians to perform successful implant rehabilitation. NI allows an optimal final location, to avoid the risk of damaging the noble anatomical structures near the site and allows the achievement of satisfactory aesthetics. The aim of this study is analyze three different systems: the RoboDent® system (Berlin, Germany, 2001), today not for sale, was the first implant navigation system introduced on the market and made the history of dynamic surgery; X-Guide (Nobel Biocare, 2017), a dynamic computer assisted system that uses the principles of stereoscopic triangulation by optical video cameras. And last, the Navident® dynamic navigation system (Toronto, Canada, 2015), produced by the Canadian company ClaroNav, evolved from the Navient brand used in orthopaedic surgery, neurosurgery and otolaryngology, sharing the motion tracking technology. Dynamic computer assisted surgery systems allow more accurate implant placement when based on an accurate 3D CT-based image data and an implant planning software which minimizes errors and simplify the surgical technique.

MRI findings of working and non-working TMJ during unilateral molar clenching on hard bolus.

The aim of this study is to evaluate with MRI the TMJs behavior during one-side clenching on a hard bolus. The sample consisted of 13 patients. an MRI of TMJ using a 1.5 Tesla superconducting magnet and a dedicated surface coil was performed in all patients. Parasagittal scans of the TMJ (perpendicular to the long axis of the condyles) were made with the mouth closed, open and with a plastic thickness 10 mm high, 15 mm wide and 20 mm long always interposed between the molars of the left side; TSE T2W and DPW sequences were used. The working condyle is always positioned behind the non-working contralateral condyle and the morphology of the retrodiscal tissue upper lamina was curvilinear in all TMJs examined. This work confirmed that, during clenching on a unilateral hard bolus, the working condyle translates less than the balancing one and that the condyle-disc ratios are substantially the same in both sides. The study of the retrodiscal tissue imaging in the different functional phases, suggest that it does not exert any pulling force towards the disc.

Appearance of normal MRI anatomy of the lingual nerve using steady-state free precession sequences at 3-T.

The aim of this study is to assess the value of SSFP MRI sequence in depicting the normal anatomy of the lingual nerve (LN), particularly in the molar region, in order to help the periodontists, dentists and oral surgeons in their daily practice. The study group included 24 patients who were to undergo MR study for a reason unrelated to our purpose. All imaging was performed by using a 3.0T system with a head and neck multiarray coil. The evaluation criteria included image quality factors such as the identification of the LN, its demarcation and its contrast to surrounding tissues on a five-point scale. The LN is clearly visible throughout its course from its origin from the mandibular nerve (MN) to the mylohyoid muscle. In edentulous patients, the LN could be damaged during surgical procedures especially it during the dissection and retraction of a lingual flap and, above all, during the suture due to a direct trauma caused by the needle or indirectly during tying the knot.

Healing of the post extractive socket: technique for conservation of alveolar crest by a coronal seal.

The first aim of the following experimental study was to assess bone changes in the horizontal and vertical dimension when using different socket preservation procedures. The second objective of our work was also to compare two clinical methods of coronal seal's management: an experimental group was treated using the natural extracted tooth; another experimental group saw the use of a provisional resin preformed as a seal technique. In twelve patients a premolar tooth was extracted without elevation of a mucoperiosteal flap and the patients were randomly distributed into four groups. The first and second group was considered as a control groups: in the first, the extraction socket was left with its blood clot and interrupted sutures were applied; In the second, the extraction socket was filled with BioOss Collagen (Geistlich Biomaterials, Wolhusen, Switzerland) and a free gingival graft was sutured to cover the socket. The third and fourth groups was considered as a test group. In the third group, after tooth extraction, for aesthetic reasons, the root of the natural dental element is cut to allow immediate temporary prosthesis. In the fourth group, as in group 3, the patient is discharged through a temporary restoration performed or by the dental technician or directly to the chair. Standardized photographs were taken eight months after tooth extraction. Five competent observers analyzed the esthetic outcome according to the PES. To assess the level of bone healing at the extraction site, the following parameters were evaluated: 1) changes in soft tissue and 2) changes in bone level. As for soft tissues, they were assessed using the PES score by two assessments, four weeks apart. The overall scores of the four treatment groups revealed PES values of 8.47 (SD 2.08, group 3), 6.62 (SD 3.24, group 4). The differences between groups 1 and 2 and were statistically significant (P=0.015 and P=0.047). The single parameter analysis displayed a certain range of fluctuation and heterogeneity. As regards hard tissue, during the 6-month period, bone remodeling occurred in all four experimental groups with different percentages. The mean vertical loss of the buccal bone plate for the Tx 1 group was -2 ± 0.2 mm. The Tx 2 group showed vertical loss of - 0.34 ± 0.2 mm. The Tx 3 group demonstrated - 0.3 mm of mean vertical loss and the 4 groups demonstrated -0.46 of mean vertical loss. The horizontal dimension of the alveolar process was 13.5 ± 0.1 mm, 7.6 ± 0.1 mm e 6.7 ± 0.1 mm at the three different levels for the Tx 1 group. The Tx 2 group depicted bone dimensions of 14.4 ± 0.2 mm, 13.7 ± 0.3 mm e 13.4 ± 0.1 mm. The horizontal dimension of the Tx 3 - Tx 4 group was 13.7 ± 0.3 mm, 13.1 ± 0.1 mm e 13 ± 0.1 mm and 13.5 ± 0.1 mm, 13.2 ± 0.1 mm e 12.9 ± 0.1 mm. The findings from the present study disclose that incorporation of coronal seals define a particular respect to the buccal bone plate.

Human Papilloma Virus associated with oral cancer and preventive strategies: the role of vaccines.

The aim of this paper is to describe the efficacy of Human Papilloma Virus (HPV) vaccines for preventing oral cancer. A systematic review of the literature was conducted to describe the state of the art about HPV vaccines for preventing oral cancer. The aspects of prevention and control of infection by administering vaccines and the diffusion of sexual education campaigns are discussed also. In recent years there has been a growing interest in HPV in dentistry, suggesting a role of such a family of viruses in the development of oral cancers as well as of the uterine cervix. Even if the mass media have increasingly faced the problem, causing frequent alarming among patients, the dentist therefore needs a complete and up-to-date knowledge of this infectious condition that is one of the most common causes of sexually transmitted mucous membrane infections (eg genital, anal and oral). Recent studies about HPV infection are a basic requirement in order to promote the HPV vaccinations and patient’s health.

HPV acting on E-cadherin, p53 and p16: literature review.

In addition to tobacco and alcohol consumption, the two main risk factors for oral squamous cell carcinoma (OSCC), recent studies have revealed infections with human papilloma virus (HPV) as an additional risk factor for OSCC development. In the field of head and neck malignancies, the prevalence of HPV infections in oropharyngeal cancer (OC) ranges in different studies up to 84%. While HPV infection is discussed as an independent risk factor in this region, its distinguished role in carcinogenesis of tumours localized to the oral cavity remains uncertain. A systematic literature search was performed using PubMed, Cochrane library, Science Direct, and the Internet search, with language restricted to English. The search included published studies which dealt with detection methods of HPV-related oral and oropharyngeal cancers and biomolecular studies, particularly regarding the compromising of p53 p16 and e-cadherin’s. P53 Tumour suppressor protein p53 has several functions that are related to maintaining genomic stability and inhibiting cell proliferation in response to DNA damage. For preventing neoplasia to occur, the most important of these functions are cessation of cell growth and induction of either apoptosis or senescence. P16 is a cellular protein involved in cell cycle regulation. It is a cyclin-dependent kinase 4 (CDK4) inhibitor, and is integral to Rb mediated regulation of G1-S phase of the cell cycle. P16 is expressed at a very low level in normal cell as Rb inhibits transcription of p16. Various detection methods ranging from immunohistochemistry (IHC) to molecular techniques have been used to determine the HPV status of HNSCC. E-cadherin, a 120 kDa Type I classical cadherin, is expressed primarily on epithelial cells. It is found on the surface of keratinocytesand Langerhans cells (LC) and E-cadherin mediated adhesion between these cell types is required for LC retention in the epidermis. It is also an important tumour suppressor protein: its loss or inactivation is associated with epithelial-to-mesenchymal transition (EMT), a process involving dedifferentiation, infiltration and metastasis of tumours. Oral carcinogenesis is a multi-factorial process involving socioeconomic, environmental and microbial factors leading to multistep changes. Smoking and tobacco exposure seems to modify the survival and recurrence of HPV positive tumours and should be considered in future trials for risk stratification of HPV positive patients. HPV associated oropharynx cancer represents a distinct clinical and biologic entity with many unresolved issues that will be investigated in future translational, clinical research. We need to further explore and understand why the disease occurs predominantly in males, and whether the natural history of oral HPV infection differences in men and women.

Colonization of Legionella spp. In dental unit waterlines.

Legionella spp. are ubiquitous in aquatic habitats and water distribution systems, including dental unit waterlines. Surveys have shown that the percentage of samples taken at different dental sites that were positive for Legionella spp. were highly variable and ranged from 0% to 100%. Cultivation is the principal approach to evaluating bacterial contamination employed in the past, but applying this approach to testing for Legionella spp. may result in false-negative data or underestimated bacterial counts. PCR and direct fluorescent counts can detect viable non-cultivable bacteria, which are not counted by plating procedures. Legionella spp., commonly form such viable non-culturable cells and it is likely that they contribute to the difference between plate count results and those of PCR and fluorescent-antibody detection. However, studies have shown that Legionella is present in the municipal water source in spite of the current filtration and chlorination procedures. Once Legionella reaches the building water system, it settles down into a biofilm layer of stagnant water. By means of this layer, Legionella can protect itself from antimicrobial agents and then multiply. Dental unit waterlines may be contaminated with opportunistic bacteria. The water quality in the dental units should be controlled to eliminate opportunistic pathogens and to provide water for dental treatment that meets public health standards for potable water.

Detection of endocarditis bacteria in tonsillar mucosa of Afghan population.

Endocarditis is a cardiovascular disease caused by the inflammation of the inner tissues of the heart, the endocardium, usually of the valves. Bacteraemia is essential in the development of endocarditis, and there are some findings that the main pathogens of endocarditis are viridans group streptococci: Streptococcus oralis, Streptococcus sanguinis, and Enterococcus faecalis. There is strong evidence that endocarditis bacteria are present in the tonsillar microbiota, so that tonsillar infection is associated with an increased risk of endocarditis. The aim of this manuscript is to investigate the presence of the main pathogens of endocarditis in tonsillar microbiota of an Afghan population group. A sample of 80 tonsil swabs were analyzed by quantitative real time PCR to detect endocarditis pathogens and an estimation of the total bacterial load. The median bacterial load in PCR reaction was 1.4x106 (interquartile range 4,7x105 - 2,9x106). Three species, S. Oralis, S. Sanguinis, and E. Faecalis were found in large amounts in all specimens. On the other hand, S. Mitis was never detected. The S. Aureus was found in 3 samples with a prevalence of 0.04 (C.I. 0.01-0.10). The S. Mutans was found in 33 samples with a prevalence of 0.41 (C.I. 0.31-0.52). Endocarditis bacteria has been found into the tonsillar microbiota, so there is sufficient evidence to justify that the oral cavity is a reservoir of endocarditis bacteria that can have a significant impact on the cardiovascular function.

Human polyomavirus in tonsillar microbiota of an Afghan population group.

Some studies have evidenced the role of human polyomaviruses in head and neck squamous cell carcinoma. BK, JC and SV40 human polyoma viruses are widely recognized as etiological agents associated with malignancies. The aim of this study was to analyse the prevalence of BK, IC and SV40 in tonsillar microbiota in a group of Afghan volunteers. A sample of the tonsillar microbiota was taken from a single site using a sterile oral swab paper stick. A fixed volume of purified DNA from each sample was tested by quantitative real-time polymerase chain reactions to evaluate the number of human cells and the number of viral genomes in each sample. The cell number was evaluated via the quantification of a single copy genomic sequence, which is located in the HMBS locus. The median analyzed cell number in each reaction was 4343 (interquartile range 2074-8470). SV40 was never detected, while prevalence rate was 0.11 (C.I. 0.06-0.20) for BK and 0.10 (C.I. 0.05-0.19) for JC. Further studies are necessary to clarify whether polyomaviruses can be considered a risk factor of oral, oropharyngeal and laryngeal malignancies.

Human papilloma virus in the tonsillar microbiota of an Afghan population group.

Cancer of the oral cavity is known to have a diverse aetiology that includes infectious agents. Human papilloma virus has been found to be associated with several types of human cancer, inclusive of cervical, vulvar, vaginal, penile, anal, and cancer of tonsil. The aim of this manuscript is to investigate the presence of human papilloma virus in tonsillar microbiota of an Afghan population group. A sample of the tonsillar microbiota was collected by oral swab paper stick from 80 healthy donors. The sample was investigated for the presence of high-risk human papillomavirus types 16, 18, 31 and 45 by real time PCR. Eight samples produced some positive endpoint signals for human papillomaviruses. The human papillomavirus 31 was the unique papillomavirus detected; its calculated prevalence rate was 0.10 (C.I. 0.05-0.19). However, the viral load was always very low, in the order of 10-3 viral genomes per cell. The high prevalence of high-risk human papillomavirus in healthy population suggest a need for further investigation on virus spreading and supports the development of vaccination strategies.

HPV infection in the oral cavity: epidemiology, clinical manifestations and relationship with oral cancer.

PURPOSE: The aim of this paper is to describe epidemiology and clinical manifestations of oral infection by Human papillomavirus (HPV), with particular attention to potential malignant lesions. MATERIALS AND METHODS: A systematic review of the literature was conducted to describe the state of the art about HPV infection in oropharyngeal mucosa and its modalities of transmission, with particular attention to possible simultaneous infection in multiple anatomic sites. The aspects of prevention and control of infection by administering vaccines and the diffusion of sexual education campaigns are discussed also. Therapeutic protocols are also described where necessary. RESULTS: In recent years there has been a growing interest in HPV oral medicine, suggesting a role of such a family of viruses in the development of neoplasms of the oropharyngeal district as well as of the uterine cervix. Even if the mass media have increasingly faced the problem, causing frequent alarming among patients, the dentist therefore needs a complete and up-to-date knowledge of this infectious condition that is one of the most common causes of sexually transmitted mucous membrane infections (e.g. genital, anal and oral). CONCLUSIONS: Recent studies about HPV infection are a basic requirement in order to promote the health of patients and provide them with the most exhaustive indications from dentists.

3D X-ray microscopic analysys on a prosthetically loaded implant with platform-switching and conical connection: a case report.

The histological and histomorphometrical examination were the gold standard in the qualitative and quantitative analyses of the peri-implant tissue around the implant. In recent years, the field of microscopy has witnessed a considerable enhancement of the performance of microscopes that have very high resolution performance and allowing very sophisticated analysis even larger than traditional preparations. The possibility to have an affordable analyses of whole implant with the surrounding different tissues (soft and hard tissues) without the traditional pre-treatment necessary for the histological analysis may represent a goal to describe material properties and behaviors or simply to visualize structural details. The aim of the present study were to evaluate a 3D X-ray microscopic analysis of peri-implant tissue compared to a traditional histological and histomorphometrical analysis of the peri-implant tissues around an implant with a conical connection associated with platform-switching in order to assess the validity of the new analysis technique.

Bone level changes around platform switching and platform matching implants: a systematic review with meta-analysis.

The amount of marginal bone loss is considered an important criterion to evaluate the implant therapy outcome and to predict the prognosis of the implant rehabilitation. The purpose of this systematic review was to examine the available literature comparing clinical and radiological outcomes like the implant failure rates and marginal bone loss around platform switching dental implants versus platform matching ones. English randomized controlled human clinical trials, comparing one or more PS groups with one or more PM groups, with at least 12 months of follow-up after loading and 10 implants, providing carefully the number of PS- and PM- implants used as well as implant survival and data concerning bone level changes or marginal bone loss around implants, were included. Fifteen publications, involving a total of 1439 implants and 642 patients, were eligible. More studies showed less mean marginal bone loss around PS implants and none of them showed differences in terms of implant failure rates. This review confirmed a great effectiveness of platform switching technique to prevent marginal bone resorption. Nevertheless, this result should be interpreted cautiously because of the heterogeneity of the included studies.

Different performance of platform switching in equicrestal position implant: an histological study.

OBJECTIVE: In this study we tested two different type of implant systems that were selected on the basis of differences in macrogeometry of platform switching in order to evaluate the behavior in term of BIC on the platform. MATERIAL AND METHOD: The patients were divided in two groups (Group I and II); group I was composed by 4 patients that each received in the posterior areas of mandible one type A implant (3,6 mm in diameter and 6,5 mm in length GTBPlan1Health Amaro (UD) Italy) one type B implant (4 mm in diameter and 8 mm in length OsseoSpeed Astra Tech, Dentsply Molndal, Sweden). Group II was composed by 3 patients that each received in the posterior areas of jawsbone one type A implant [3,6 mm in diameter and 6,5 mm in length GTB- Plan1Health Amaro, (UD), Italy] one type B implant (4 mm in diameter and 8 mm in length OsseoSpeed Astra Tech, Dentsply Molndal, Sweden). All the implants were placed, by the same operator, in equicrestal position using "one stage" technique with a healing abutment at an adequate gingival height. After 12 weeks of healing all the implants of both groups were harvested with the peri-implant bone tissues. BIC upon platform was calculated considering as implant surface the platform length. RESULTS: Our results showed that the mean percentage of BIC value related to platform surface placed in equicrestal position was higher in patients with type A implant than patients receiving type B implant independently from mandibular or maxillary positions. Moreover the mean percentage of BIC related to platform surface was significantly (p<0.05) higher in Group II/A than Group I/A. CONCLUSIONS: Our data highlights that the particular features of the Bioplatform of Type A implant systems guarantee a higher value of BIC even if the implants were placed equicrestally.

Preservation of extraction socket in immediate implant placement: a clinical study.

AIM: The objective of this study was to compare different approaches temporary restoration in an immediate implant placement. To determine the respective influence of each parameter, two treatment groups were formed; a strict and standardized study protocol was applied to minimize the influence of bias and confounding factors. The Pink Esthetic Score (PES) - the esthetic out-come of soft tissue appearance was evaluated. MATERIAL AND METHODS: Sixteen patients with a single failing tooth in the maxilla and a natural contralateral site were randomly distributed into two groups. Treatment variations affected the provisional restorative in detail, group 1 with immediate implant placement and immediate temporary restoration with the simulation of the first three mm of the root and the seal of the socket, group 2 with immediate implant placement and immediate temporary restoration without the seal of the socket. All patients received the final prosthetic restoration 10-12 weeks after implant placement. Standardized photographs were taken eight months after tooth extraction. Five competent observers analyzed the esthetic outcome according to the PES. RESULTS: The overall scores of the four treatment groups revealed PES values of 8.47 (SD 2.08, group 1), 6.62 (SD 3.24, group 2). The differences between groups 1 and 2 and were statistically significant (P=0.015 and P=0.047). The single parameter analysis displayed a certain range of fluctuation and heterogeneity. CONCLUSIONS: Immediate implant placement and restoration appear to be a suitable alternative to early implant placement if an experienced surgeon is entrusted with the implantation procedure.

Implant Dentistry: Monitoring of Bacteria Along the Transmucosal Passage of the Healing Screw in Absence of Functional Load.

PURPOSE: To assess the changes in bacterial profile along the transmucosal path of healing screws placed immediately after insertion of two-piece endosseus implants during the 4-month osseointegration phase, in absence of functional load. MATERIALS AND METHODS: Two site-specific samples were collected at the peri-implant mucosa of the healing screws of 80 two-piece implants, for a total of 640 samples. Implants placement was performed following a single protocol with flapless technique, in order to limit bacterial contamination of the surgical site. Identical healing screws (5 mm diameter/4 mm height) were used for each of the 80 implants. During the 4 months of the study, the patients followed a standard oral care regimen with no special hygiene maneuvers at the collection sites. RESULTS: The present research documents that during the 4-month period prior to application of function load the bacterial profile of all sites exhibited a clear prevalence of cocci at the interface between implant neck and osteoalveolar crest margin. CONCLUSIONS: A potentially pathogenic bacterial flora developed only along the peri-implant transmucosal path.