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Aim: To assess the quality of proximal coronary restorations and bring out the factors influencing this quality., Material and Method: A transversal study on 160 radiographs of proximal coronary restorations was conducted at the University Center of Dental Consultation and Treatment of Rabat. Restorations were evaluated according to the modified USPHS criteria. Four variables were studied: restoration material, treated tooth, cavity type and location of treatment in order to identify the influencing factors., Results: Forty five per cent of the evaluated proximal coronary restorations required replacement. The main cause of failure was recurrent caries in 36% of cases, followed by the absence of the contact point (24.4%), unacceptable proximal coronary outline (13.8%), and finally dentin exposure (6.9%). Thus, it turned out that there is a difficulty to restore correctly posterior proximal cavities especially using amalgam and a high rate of recurrent caries at both the anterior and posterior teeth., Conclusion: Both a clinical and a radiographic evaluation after each proximal restoration would be recommended to reduce failure.

Introduction: The aim of this study was to compare the leakage at the implant to abutment connection in several implants, using a new gas diffusion method., Material and Methods: Sixty-eight implants of 13 different types were used. Nitrogen leaking was measured after screwing the connections to the torque levels recommended by the manufacturers., Results: A significant tightness difference was observed between the different implant types. This difference cannot be explained by the various connection designs (flat, conical) or by the various torques recommended by the manufacturers., Conclusion: The authors suggest that the tightness difference between the various implant systems could be mainly associated with quality and precision of machining., (Copyright © 2013 Elsevier Masson SAS. All rights reserved.)

Cohesive fracture of the veneering ceramic (chipping) is the first cause of failure of zirconia-based prostheses on natural teeth and implants. Besides risk factors related to the material (thermal stresses generated during the manufacturing process, framework inappropriate design), there are some clinical risk factors, which can influence the restoration prognosis. Indeed, unfavorable occlusal relationships and/or the presence of parafunctions such as bruxism and clenching, which are frequent pathologies, engender significant overloading. A retrospective study was performed at the University Hospital Center (CHU) of Liege on 147 dental and implants prostheses, placed between May 2003 and January 2012. This study highlighted a significant correlation between chipping and the absence of an occlusal nightguard (p = 0.0048), the presence of a ceramic restoration as an antagonist (p = 0.013), the presence of occlusal parafunctions (p = 0.018), and the presence of implants as support of the restorations (p = 0.026). These results underline the importance of external stress and occlusal risk factors diagnosis, as the need to perform an occlusal nightguard to patients with parafunctions.

Objective: Failure of tooth restoration is a major clinical problem of interest to patients, dentists and employers of labour. This study was designed to find out the average life span of amalgam as well as causes and management of failed amalgam restorations at the dental center, University College Hospital, Ibadan. The distribution of new caries in patients with this condition was also investigated., Materials and Methods: This was an interventional study conducted among consenting patients who presented with failed amalgam restoration in our conservative clinic over a three-year period. Oral examination was conducted to detect primary caries and causes of failure of the restoration. Bitewing radiograph was taken where necessary. The following data were recorded: socio-demographic variables of the patients and their complaints; life span of the failed restorations and the treatment given. Summary statistics was generated., Results: One hundred and forty three patients (54 males, 89 females) presented with 198 defective restorations. Sixty five (45.5%) of these had 118 new carious lesions which were majority occlusal cavities (66.9%). Fractured restoration was the commonest cause of failure. Management was variable, but replacement with amalgam was the commonest treatment. The average life span of restoration was 8.3 years., Conclusion: The average life span of amalgam restoration was 8.3 years and the major cause of failure was amalgam fracture. Replacement with amalgam was the commonest treatment.

It has become increasingly common for diabetic patients to be considered as candidates for dental implants. However even though success rates of implant therapy in diabetic are high, this does not preclude failures. Failure to osseointegrate in the initial healing phase results in a fibrous tissue encapsulation of the implant and clinical mobility, leading ultimately to the failure of the implant. This review presents the current knowledge regarding the effect of diabetes mellitus on the osseointegration of implants including pathophysiologic aspects as well as their potential implications on bone metabolism and osseointegration, implant success rate at the second-phase surgery and guidelines for pre and post-operative management. In experimental models of diabetes mellitus, a reduced level of bone-implant contact has been shown, and this can be reversed by means of treatment with insulin. Compared with the general population, a higher failure rate is seen in diabetic patients. Most of these occur at the second-phase surgery, seemingly pointing to the microvascular complications of this condition as a possible causal factor. It is necessary to take certain special considerations into account for the placement of implants in diabetic patient. A good control of plasma glycemia, together with other measures, has been shown to improve the percentages of implant survival in these patients.

The obturating prostheses of the jawbone and the prostheses of rebuilding of the mandible make it possible to restore the losses of substance of the jawbone and of the mandible and to cure the functional and Aesthetic disorders which result from these losses of substance. The success of these prosthetic restorations can be compromised by technical, economic and cultural factors. The principal factors are the importance of the losses of substance, the reduced number of teeth, the poverty of the technical plate, the persistence of certain traditional concepts. The fight against these factors requires the promotion of therapeutic associations in maxillo-facial cancerology, the sensitizing of the populations to the early hospital consultations, the improvement of the technical plate of the prosthesis of the jawbone and the face, the facilitation of the access of the most underprivileged groups to the prosthetic restorations, the promotion of multi-field collaboration, the whole co-operation of the patient throughout the treatment and the follow-up postprothetic.

Results of immediately loaded implants are presented. 34 patients with 136 interforaminal MonoType implants (Straumann,Basel, Switzerland) were included in the study. The bar retention was manufactured fter the operation, inserted and covered with a hybrid prosthesis. 28 patients showed up for the follow-up study, the average time range was three years. Five implants were rated as failures, the cumulative six-year success rate being 94%. Interforaminal immediately loaded MonoType implants in edentulous patients showed very good results, comparable to similar studies with different systems.

The reconstruction of the severe atrophy of the maxilla using dental implants requires extensive surgical treatments. Sinus lift procedure, ridge augmentation with free bone grafts or free vascularized bone transfers represent the common techniques. With regard to a higher life expectancy the number of patients suffering from limited chewing function based on atrophic bone conditions will increase. In addition to a higher number of failed implants in elderly people ask for other treatment strategies to regain proper oral function with limited surgical effort. This case report presents the failed treatment of maxilla, using disc implants and shows the new maxillary reconstruction using Brånemark-Zygoma implants combined with standard Nobel Replace implants in order to avoid extensive augmentation procedure.

Thirty-six inlays, equally divided between a vitro ceramic and a composite resin, were bonded in pair, on the same type of teeth in fifteen patients. They were followed for a mean period of 75 months. The results showed that both materials were clinically acceptable for restoring posterior teeth, even though ceramic yielded significantly better results concerning colour match and surface roughness.

Introduction: The purpose of this study was to evaluate the implant placement outcome in edentulous patients prosthetically rehabilitated after autogenous bone graft., Material and Method: Between 2002 and 2006, 75 patients underwent graft surgery, only 64 patients (mean age of 53.8 years) had a complete treatment. Calvarial bone grafts were used in 41 cases, mandible bone in 13 cases, and iliac bone in 13 cases. Grafting techniques were onlay and inlay grafts in the maxilla combined or not with LeFort I osteotomies, and onlay or interposed bone graft in the mandible. Twelve patients presented with complications, wound dehiscence in seven cases and infection in five cases. Twenty-two patients presented with perforation of the sinus mucosa in the course of sinus lift., Results: Three hundred and seventy-nine implants were inserted in 64 patients, 295 in the maxilla and 84 in the mandible. Fifteen implants failed (3.95%), 13 before loading and two after, 10 maxillary implants (3.38%), and five mandibular implants (5.95%). The global implant survival was 96.05% with a mean background of 23.6 months, 88.37% after sinus lift, 83.33% after apposition graft in the mandible and 88.64% in the maxilla., Discussion: These results correlate to current published data.

Introduction: The use of bone substitutes in massive sinus-lift pre-implant procedures remains controversial. The aim of our study was to evaluate the long-term reliability of pure-phase beta-tricalcium phosphate (betaTCP, Cerasorb, Curasan, Kleinostheim, Germany) used in this particular indication., Material and Method: Twenty patients (33sinus) presenting with severe sinus floor atrophy (class 4 to 6 according to Cawood) and having undergone a sinus lift procedure by mean of betaTCP were followed in a prospective study between January 2002 and May 2008. The surgical approach was classical (under local anesthesia in eight patients) and the sinuses were filled with betaTCP (6 cm3 on average per sinus) and autologous growth factors (platelet rich plasma PRP and platelet rich fibrin PRF, according to the technique described by Dohan and Weibrich). One hundred and twenty-three dental implants were inserted in the grafted sinuses between the fourth and the eighth postoperative month (Nobel Biocare MK III and MK IV-mean length: 12.44 mm) using a 2-step buried technique and loaded between the fourth and the sixth month. Follow-up included regular clinical examination and panoramic X-rays to screen for possible sinus and implant complications. The control X-rays also allowed measuring the biomaterial resorption rate., Results: The mean postoperative follow-up was 4.5 years for the sinus lift procedures and 4 years for the implants. We noted one case of local infection at the 15th postoperative day (3%). The implant success rate was 97.6% (lack of osteo-integration for two implants in the same patient, one failure after loading). The prosthetic success rate was 100%. The mean resorption rate of the material was 20.3% and the mean gain of height was 16.9 mm., Discussion: The use of betaTCP associated to growth factors (PRP ou PRF) without bone graft, in massive sinus-lift procedures induces few complications. The implant success rate is comparable to the one obtained by using autologous bone grafts. The resorption rate of the material is comparable to that of autologous bone.

This case report presents the treatment sequence of a 56 years old patient after he developed periimplantitis at the implant in position of tooth 22. This implant was integrated in an overdenture reconstruction connected to a soldered screw retained gold bar. The entire 2-stage procedure of implant explantation, simultaneous bone augmentation and new implant placement is documented. The onlay-graft was performed by means of the Transfer-Ring-Control System (Meisinger). The existing gold bar could be resoldered and adapted to the new implant. Accordingly the overdenture was relined and the female retainer mounted. The treatment period covered almost one year.

Periapical surgery is required when periradicular pathosis associated with endodontically treated teeth cannot be resolved by nonsurgical root canal therapy (retreatment), or when retreatment was unsuccessful, not feasible or contraindicated. Endodontic failures can occur when irritants remain within the confines of the root canal, or when an extraradicular infection cannot be eradicated by orthograde root canal treatment. Foreign-body reponses towards filling materials, towards cholesterol crystals or radicular cysts might prevent complete periapical healing. Following enhanced microsurgical techniques in the last years the success rates of apical surgery have improved considerably. The aim of the current case report is to describe the therapeutical approach to a persistent periapical lesion and its histologic examination.

Introduction: Osteoradionecrosis (ORN) is a severe complication of radiation therapy (RT). A triggering factor is frequently present. It is often a dental, periodental, or surgical traumatism. We report the case of a bilateral ORN: the first lesion appeared 3months after the end of RT around the osteosynthesis plate and was treated by mandibular resection. The second lesion appeared 40months after RT on the opposite side, due to peri-implantitis. Dental implants had been inserted 10years before cancer therapy. No case of ORN in post-implantation RT had been previously reported., Case Report: A 75-year-old woman was admitted for a squamous cell carcinoma of the right cheek extending to the intermaxillary commissure, the maxillary tuberosity, the soft palate, the lingual junction, and the vestibule up to the second premolar area. There was no suspicious lymph node. She had undergone dental implant procedure 15 and 10 years before, respectively, one in the second premolar position of the right maxilla and four in the premolar and molar left mandible area. All of them were osseo-integrated and charged. A trans-mandibular buccopharyngectomy with modified radical neck dissection was performed, completed by RT. The total dose of irradiation was 65Gy in the oral cavity and 45Gy on cervical and supraclavicular areas. Delayed mucosal healing was observed on the right mandible and ORN appeared in this area 3months after the end of irradiation. Mandibular resection was necessary. Later, the right maxillary implant was lost, and multiple dental extractions were required. Forty months after RT, peri-implantitis was observed on the left side of the mandible, complicated by ORN and pathological fracture. No surgical reconstruction could be performed because of the patient's age and state. The patient was carrying a complete removable maxillary prosthesis on latest follow-up., Discussion: This was the first case of ORN on dental implants placed before RT. RT is a risk factor of implant failure, a relatively rare and unpredictable event. Most often, it causes implant loss and exceptionally ORN. In our case, ORN was bilateral. The first lesion was probably due to surgical trauma. The second one, on the opposite side, was caused by peri-implantitis. Irradiation overdose on the alveolar mandibular ridge, close to the implant, may have been the cause. In our case, there was no severe pain, and slow evolution led to a pathological fracture.

The purpose of this study was to determine radiographically the prevalence of periapical periodontitis in teeth restored with crown in a Senegalese population. Full mouth periapical radiographs were obtained from 208 consecutive adult patients (6234 teeth) presenting as new patients to the Dental Service of the University. The presence of crown restorations, the periapical status and technical quality of root fillings associated were evaluated. 7.69% (n = 16) of patients had at least one tooth that was crowned. The total number of crowns assessed was 0.95% (n = 59). The molars were the teeth most crowned 40.67% (n = 24) followed by anterior teeth 30.50% (n = 18) and premolars 28.81% (n = 17). All the crowned teeth had previous root canal treatment of which only 16.94% (n = 10) were acceptable. 53 % (n = 32) of the teeth had apical periodontitis (PAI > 2). Unacceptable root fillings were associated with a higher prevalence of periapical disease (p < 0.05). Crown with a post extending more than 4 millimetres from the apex were associated with more periapical lesions 64.28% (p < 0.05). The results indicate a low prevalence of crowned teeth, an absence of vital preparation, a high prevalence of radiographic periapical disease and unacceptable root fillings associated.

The two direct dental restorative materials most commonly used today are silver-mercury amalgam and resin-based composite. The survival of dental amalgam restorations is twice as high than for composite fillings: polymerisation shrinkage, deficient marginal adaptation, higher wear rates, defective contact points leading to food impaction, insufficiently converted composite at the bottom of the cavity are problems that cannot be underestimated when using resin-composite. This does not imply that there is no weakness for amalgam: the need for retentive cavities at the cost of healthy tooth substance, weakening of the tooth's strength by cutting through the tooth crown's ridges, the risk of fracture of remaining tooth substance (mostly buccal and lingual surfaces) as the result of the cavity design, and the lack of adhesion between amalgam and tooth substance. Retaining a tooth's strength by the replacement of amalgam by resin-composites is not always the correct solution. In this respect, it can be questioned whether it is not appropriate to repair failing (extensive) amalgam restorations as to replace them with resin-composites. Research in this respect has demonstrated that dentists still are not convinced of this treatment option. Restoring a tooth in its original build-up or structure and function within the oral cavity is the basis of the biomimetic principle: the use of composite appears to be more obvious than restoring with amalgam. In the present survey pro's and con's of amalgams and resin-composites for the restoration of posterior teeth are weighted. The conclusion demonstrates that there is still a place for dental amalgam in modern restorative dentistry when plastic filling materials are used for the direct tooth repair or restoration.

The range of bone regeneration materials suitable for maxillar bone augmentation has increased steadily in the past few years and there is now a wide variety of materials being used. In the present case report, we analyzed the state of bone regeneration after sinus floor augmentation using a nanocrystalline in-phase synthetic anorganic hydroxyapatite bone grafting material (Ostim). A 60-year-old female patient underwent maxillary sinus floor elevation and the cavity was filled with Ostim three years before. Actually, she presented herself with loosening of the dental implant at position 17, as a result of parafunction. At the time of the insertion of a second implant at position 17, bone samples were taken by using a trepan drilling device from the previously augmented area. These samples were analyzed histologically to determine the extent of bone remodeling around the deposits of Ostim. We found that the Ostim deposits were surrounded largely by woven bone and, in parts, by lamellar bone and had facilitated osteoconductive bone regeneration. The adjacent implant, at position 16, which beared a crown exposed to proper biting forces without parafunction, showed proper clinical and radiological characteristics of complete and firm integration into the area which was also filled with Ostim three years ago. We conclude that the use of the nanocrystalline hydroxyapatite Ostim with its stable volume properties appears to be suitable for maxillary sinus floor augmentation. Furthermore, we even found osteoconductive bone regeneration under Ostim near the site of the loosened implant.

In this prospective clinical study on 40 patients with similar clinical conditions (edentulous jaw with 2 interforaminal implants) commercially available ceramic ball attachments (ruby) were compared to commercial titanium ball attachments. The primary aim of the study was to measure the wear of the ball attachments after being 1 year in function. However, in the course of the study already after 7 to 12 months multiple failures with ceramic ball attachments occurred. Twelve (28%) of 43 ceramic ball attachments had to be replaced, mostly because of fractures (8) of the ceramic ball. It seems that ceramic ball attachments of the investigated design are not able to withstand normal intraoral stresses. The short-term susceptibility to fractures didn't allow to examine the ceramic-inherent features such as compressive strength and wear resistance. Furthermore, a secure connection between a titan base and a ceramic ball seems to be challenging. Based on these results, in implant-retained removable prosthesis the use of metal-based retainers is still recommended, although during maintenance a higher wear has to be expected. This wear can be compensated by either activating or changing the matrix or the patrix.

Reverse piezoelectricity is currently used in Dentistry for ultrasonic scaling devices. Using this technology, increasingly more powerful ultrasonic surgical lancets were developed within a few years, and these new tools have provided many practical solutions in oral and maxillofacial surgery. This article reviews the basic principles of piezosurgery, and its numerous clinical applications: in oral surgery (atraumatic extractions, wisdom teeth exposure, periapical cyst debridement, pre-prosthetic surgery), more specifically in periodontal (root planning and bone remodeling, crown lengthening) and implant surgery (sinus lift, removal of fractured implants, bone ridge augmentation, bone graft harvesting (crestal, retromolar, chin or tori)). The recent increased power of these instruments allows emphasizing a much wider range of clinical applications, extending to all surgical fields.

The new Swiss implant system SPI became available three years ago and is used in combination with fixed and removable prosthetic reconstructions. In a pilot study the clinical procedures were evaluated and data of prosthetic complications of maintenance service were collected. 25 patients participated in the study with a total of 79 SPI implants during the time period from 2003-2004. 37 implants were located in the maxilla and 42 implants in the mandible. Two implants failed during the healing period, but no loaded implant was lost. Thus, the survival rate was 97.5% (77/79). 44 implants supported a fixed prosthesis, including nine single crowns and 33 implants were used in combination with removable partial denture. Four implants were used with ball anchor retention, 29 with bar support. The ELEMENT implant with the low implant shoulder allows very good esthetics. Prosthetic complications and maintenance service during the first year of function was comparable with other implant systems. Since the design of the abutment screws, healing caps and screwdriver was changed, the system has become easier in its application.

Clinical aspects of a simple treatment concept with fixed prostheses in the edentulous jaw are described. Fixed implant-supported reconstructions in the edentulous jaw require multiple implants, are technically complex, aesthetically demanding and metal-ceramic solutions are expensive. Specific surgical techniques to enhance the hard and soft tissue conditions become often necessary. Thus the bar-supported overdenture may be preferred, because problems with aesthetics and alveolar ridge deficiencies can be solved more easily and the number of implants is reduced. Both, the "All-on-Four" technique and the "Procera implant bridge" are simple type of fixed prostheses, comparable to overdentures or complete dentures with regard to design and technology. They present a cost-effective alternative, with predictable aesthetics and optimum passive fit.

Introduction: Apposition grafting is a method of choice for reconstruction of the anterior maxillary. The purpose of this work was to evaluate the success rate, the degree of bone resorption and the osteointegration of these grafts., Material and Methods: We reviewed retrospectively 36 cases of pre-maxillary bone apposition in patients operated from 1998 to 2002. Autografts were used for all patients. The harvesting site was parietal for 24 patients, intraoral for 8 and iliac for 4., Results: There was two graft failures. The success rate was 94.5%. Partial resorption with effect on implantation was noted in 3 patients. Eighty implants were inserted successfully in 234 grafted sites with on average 2.4 implants per graft. Three implants were removed. Implant survival was 96.2%., Discussion: This study demonstrated that the premaxillary apposition technique using autologous grafts provides sufficient bone volume to enable optimal implant insertion and stability.

Objectives: We assessed the reliability of maxillary bone grafting and implant stability, comparing our results with reports in the literature., Material and Methods: This retrospective series included 44 patients who underwent maxillary sinus bone grafting between 1998 and 2002. An analogous graft was used for 31 patients and a combination autologous-bone substitute graft for 13. One hundred twelve dental implants were positioned at the grafting site (2.5 implants per graft). We assessed recipient site morbidity, bone graft integration and stability, and stability of the implants., Results: Bone grafting was successful in 97.8% of patients. There was one failure. Two of the 112 implants failed., Discussion: Our results are comparable with those in the literature. This study demonstrated the reliability of maxillary bone grafting with equivalent results using autologous bone and combination autologous bone-bone substitute.

Endodontic failures on premolars are statistically important. This is mainly due to insufficient knowledge of the typical anatomical diversity shown by premolars. Filling a second root canal is often omitted. Completely treating a complicated root canal system is technically quite difficult which results in a relatively high level of endodontic failure. There are not only the classical technical problems to deal with: calcification of the root canals and delicate probing, given the frequently bent and twisted premolar roots; special attention should also be given to upper premolars with three root canals and those showing a high bifurcation of a principal root canal (configuration IV), and to lower premolars with multiple root canals often showing configuration IV. An additional problem associated with the second lower premolars is a hazardous anatomical zone: the mandibular vasculonervous plexus of the chin.

The frequent endodontic failures on premolar teeth can be partly attributed to their complicated root canal anatomy. Anatomical studies were initiated almost a century ago by W. Hess, resulting in the actual meticulous classification. Vertucci was the first to describe in an exhaustive way the scores of anatomical variations by assigning them to 9 types. The Wein model is just as complete but offers a more clinical approach. It will be used as reference in this article to weigh the various statistics appearing in the anatomical studies on premolars.