Muhamad Abu-Hussein1*, Nezar Watted2 and Dror Shamir3
1Department of Pediatric Dentistry, University of Athens, Greece
2University Hospital of Würzburg Clinics and Policlinics for Dental, Oral and Maxillofacial Diseases of the Bavarian Jul ius-Maximilian-University Wuerzburg, Germany and Center for Dentistry research and Aesthetics, Jatt, Israel
3Department Oral and Maxillofacial Surgery, Bnai Zion Medical Center, Haifa, Israel
Received: 21 June, 2016; Accepted: 07 July, 2016; Published: 09 July, 2016
Abu-Hussein Muhamad, DDS, MScD, MSc, M Dent Sci (Paed Dent), FICD, 123 Argus Street, 10441 Athens, Greece, E-mail:
Abu-Hussein M, Watted N, Shamir D (2016) A Retrospective Study of the AL Technology Implant System used for Single-Tooth Replacement. Int J Oral Craniofac Sci 2(1): 039-046. 10.17352/2455-4634.000017
© 2016 Abu-Hussein M, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
AL-TechnologyImplant; Single tooth replacement; Success rate
Objective: The objective of this retrospective study was to evaluate the success rate of AL-Technology implants used for single tooth replacement after a minimum of three years of loading at Center for Dentistry, Research & Aesthetics, Jatt, Almothalat, Israel.
Method: Dental records for 43patients who underwent single tooth replacement using AL-Technology implant system at Center for Dentistry, Research & Aesthetics, Jatt, Almothalath, Israel during a three years period (2010-2012) were retrospectively analyzed. Only implants that were functioning for at least three years were included.
Results: 152 AL-Technology implants were used for the replacement of single teeth in 43patients, 114(75%) implants were placed in the posterior regions, and 38 (25%) implants were placed in the anterior regions. All implants were restored with cement-retained crowns and have been in function for at least three years. Out of the total 152implants, two (1,3%) were considered failures as a result of significant radiographic bone loss. Therefore, the survival rate at three years was 98,7%.
Conclusion: The results of this study suggested that AL-Technology implants could be a satisfactory choice for anterior and posterior single tooth restorations.
The clinical success of dental implants is dependent on successful osseointegration. An important parameter for achieving osseointegration is the establishment of direct contact between the surface of the implant and the surrounding bone. There have been numerous studies indicating that implant surface roughness affects the rate of osseointegration [1-4].
Dental implants represent the state-of-the-art treatment for replacing single missing teeth, as demonstrated by several long-term follow-up studies, with satisfactory high survival rates [1-4]. However, biological and prosthetic complications still affect single crowns (SCs) supported by dental implants [2,5-10]. Biological complications include complications that affects only soft tissues (such as pain and swelling after surgery, or peri-implant mucositis) and complications that affect both soft and hard tissues (such as peri-implantitis) [5,6,10]. Prosthetic complications include mechanical complications (i.e. complications that affect prefabricated implant components, such as screw or abutment loosening, screw or abutment fracture) and technical complications (i.e. complications that affect superstructures, such as fracture/chipping of veneering materials and the need for recementation) [9-13].
In general, prosthetic complications, such as abutment screw loosening, loss of retention and fracture of the veneering material are the most frequent complications encountered [2,6-10,13-17]. Clinical studies on single-unit restorations have reported abutment screw loosening percentages between 5% and 48% [2,6-10,13-16]. These complications seem to affect mostly the posterior chewing, where the mechanical loads are higher [9,10,14-16].
Although abutment screw loosening may not lead to implant failure, it represents a problem, because it takes time to remove the crown and screw it again; moreover, where frequent, screw loosening may adversely affect the patient’s satisfaction with the implant treatment [5,6,12,13]. Now-a-days, in fact, patients have high functional and esthetic expectations in relation to dental therapies . Since patient satisfaction is a key, it is therefore very important to minimize the incidence of complications . Screw loosening has been generally related to the type of implant/abutment connection used. Screw type connections, such as butt-joint indexed external or internal connections, are still the most commonly used in the market [14-16]. These connections are mainly stabilized by the axial preload of the abutment screw: as a consequence, optimum preload is critical for joint stability [14-16]. The stability of butt-joint connections can be challenged by occlusal loads: when these exceed the resistance of the torqued implant- abutment system, screw may lose or break [14-16]. In addition, screw loosening may occur as a result of fatigue, when lower masticatory forces, applied repeatedly, surpass the failure threshold of the assembly [14-16].
The objective of the present study was to evaluate the success rate of AL-Technology implants used for single-tooth replacement after a minimum of three years of loading at Center for Dentistry, Research & Aesthetics, Jatt, Almothalath, Israel.
Materials and Methods
All patients planned for replacement of missing teeth by dental implants were assessed clinically by our clinical team carefully before initiating their treatment. Patients were selected on the basis of the following inclusion criteria:
- Patient age ≥ 19
o The presence of one or two missing teeth per edentulous space.
o Adjacent teeth structurally sound and esthetically acceptable to the patient.
o Maladaptive experience or refusal to wear a removable partial prosthesis or conventional bridges.
o Adequate interarch space for abutments, prosthetic components, and prosthesis.
o The vital anatomic structures are far away to the proposed implant site.
o Physically and psychologically able to tolerate conventional surgical and restorative procedures
− Women who report a current pregnancy
o All patients with chronic diseases like uncontrolled diabetes or psychiatric illness.
o Unrealistic patient expectations of the treatment with respect to esthetic comfort and function.
o Insufficient bone dimension for implants.
− -loss or damage of the buccal bone crest (>5 mm) after extraction of the failing tooth
− -need for major bone augmentation procedures with autogenous bone or bone substitutes prior to implant insertion, to obtain an ideal position for the implant (although a minor augmentation procedure to cover exposed threads or interproximal/ buccal grafting owing to hard tissue deficiency was not an exclusion criterion)
− -radiotherapy in the maxillofacial region
− -treatment with intravenous amino-bisphosphonates
− -parafunctions (bruxism or clenching)
Patients were seeking treatment to restore the missing teeth created by tooth loss resulting from caries, periodontics, endodontics complications, trauma, and congenital deficiency. The edentulous areas that were to receive the implants, as well as the adjacent structures, were evaluated using an appropriately prescribed combination of periapical, occlusal, panoramic radiographs. Before applying each implant, orthopantomogram was carried out for each patient, sometimes completed with intraoral x-ray images. In order to find out the thickness of alveolus, we made use of dental CT analysis or mapping the gingiva, using a hypodermic needle with a rubber disc. Most patients were instructed on dental hygiene. Recall examinations were carried out according to the previously published scheme.
Dental records for 43 patients who underwent single tooth replacement using AL-Technology implant system at Center for Dentistry, Research & Aesthetics, Jatt, Almothalat, Israel during a four year period (2010-2012) were retrospectively analyzed. Only implants which were functioning for at least three years were included. For the objective of this study, the success rate was recorded according to the criteria suggested by Albredtsson et al., as follows: The unattached implant is immobile when tested clinically, no evidence of peri-implant radiolucency appeared radio graphically, vertical bone loss is less than 0.2mm annually after the implants’ first year of service, absence of persistent and/or irreversible signs and symptoms such as pain, infection, neuropathies, paresthesia, or violation of the mandibular canal .
The patients were recalled one week, four weeks, and eight weeks following screw implant insertion in the bone. The second stage started after eight weeks in order to fabricate the final prosthesis. After placement of final crowns, all patients were reviewed at two weeks, three weeks, and six months. The condition of the prosthesis, implant stability and adjacent mucosa were all evaluated at each recall appointment, patient symptoms were also recorded and used along with the clinical and radiographic signs to diagnose the implant status.
The following success criteria were applied in evaluating each implant: (1) No clinically detectable mobility when tested with opposing instrument pressure; (2) No evidence of peri implant radiolucency on periapical radiographs; (3) No recurrent or persistent peri-implant infection; (4) No pain at the site of treatment; (5) No neuropathies or paraesthesia; (6) Crestal bone loss not exceeding 1.5 mm by the end of the first year of functional loading, and less than 0.2 mm/year in the following years .
AL-Technology implants were used in all cases. The length and the diameter of each implant were determined by bone quality and quantity at each surgical site. The surgical protocol required crestal implant placement, and following manufacturer’s instructions. Primary stability was assessed using a torque wrench, based on Testori’s scores.[18,19]
The treatment objective involved delivery of the provisional prosthesis within 4 hours of implant placement, by utilizing a prosthetic procedure that best fits the individual clinical condition.
The design of the prosthesis was determined by collaboration between the treating doctors, so it is consistent with the study’s objectives. A metal reinforced acrylic provisional bridge was used for cement-retained restorations. A resin hybrid restoration was used for screw retained restorations. The occlusion was carefully adjusted.
No specific diet was recommended to the patients. The patients were on a strict recall program during the first 6 months: every week during the first month, and every month between the second and sixth months. Panoramic radiographs and radiovisiography were obtained for image analysis immediately after implant placement, so per implant marginal bone changes can be recorded.
AL-Technology was founded in 2001 as an association of mechanical engineers, dental technicians, experienced dentists and oral surgeons. The result of this combination of experience and knowledge are excellent dental products, particularly in the field of implantology. AL-Technology manufactured on modern and special CNC-controlled machines. The special shape of the implants, especially the conical offers easy implantation, maximum mechanical strength, stability immediately after implantation, and high bone integration.
The special treatment of the surface ((SLA: sand blasted, Large grit, Acid-etched), the special packaging of the implants in glass vials without plastics, in a sterile environment, guaranteed ALTechnology implants of excellent quality and the highest success rate. Implants material: Titanium alloy Ti-6Al-4V ELI, Grade-5. Al-Technology Dental Devices implants and abutments are made of titanium alloy Ti-6Al-4V ELI.
All implants used in the study are the AL-Technology implant system having a titanium-alloy threaded-body design with an internal connection feature. Implants were supplied in lengths of 8, 10, 11.5, and 13 mm and diameters of 3.3,3.75,4.2 and 5 mm.
Ice packs were provided postoperatively. The patients were given anti-inflammatory and analgesic medication, consisting of 100 mg nimesulide every 12 h for 2 days. All patients received oral antibiotics, amoxicillin and clavulanic acid, 2 g each day for 6 days. Chlorhexidine 0.12% mouth rinses were prescribed for 2 weeks to enhance plaque control. Patients were instructed to eat a soft diet for 7 days and maintain daily hygiene after surgery. Smokers were told to avoid smoking for 48 h postoperatively. Patients were then observed after 2 weeks for a postoperative control and sutures were removed (if present).
Final restorative phase
After 3 months, the provisional restoration was replaced by a final restoration. Briefly, the final implant impression was made with individual trays using polyvinylsiloxane or polyether. A standard pre-fabricated titanium abutment was prepared, finished and tightened to 25 N/cm2 torque. The final restorations comprised metal-ceramic crowns and zirconium-ceramic crowns, depending on patient requirements, which were screwed to the implants.
The occlusion was checked using standard occluding papers all final restorations were carefully evaluated for proper occlusion, and protrusion and laterotrusion were assessed on the articulator and also intraorally. The restorations needed to have occlusal surfaces similar to those of natural teeth, with occlusal contacts in maximum intercuspation and with functional contacts during lateral and protrusive excursions. Finally, an intraoral radiograph was made to check final restoration seating. Patients were included in a maintenance program to achieve optimal hard and soft tissue healing, which comprised professional oral hygiene every 6 months
Data analysis was performed by an independent investigator who was not directly involved in the study. Databases were created with Excel 2003 (Microsoft Excel; Microsoft Corporation, Redmond, WA, USA) and used for the analysis.
Out of the total 43 patients, there were 29 females (67%) and 14 males (33%). The minimum age of the participants was 19 yrs, and the maximum age was 72 yrs 3 months (mean, 44,3 yrs). 7 patients were smokers. 152 single tooth implants were placed, 114 implants were placed in the posterior region, and 38 were placed in the anterior region. 59 implants were placed in the mandible (39%) and 93 implants were placed in the maxilla (61%). Data regarding the number of implants and duration of placement are presented in Tables 1-3.
All implants were restored with a cemented restoration using the solid conical abutment. The predominant type of implants placed was the solid screw. Regarding the length and diameter of the implants, 28 implants were 3,3 mm in diameter and 8,10,11.5, 13mm in length (18%), 91implants implants were 3,75 mm in diameter and 8,10,11,5,13mm in length(60%), 18 implants were 4,2 mm in diameter and 8,10,11.5, 13mm in length (12%), and 15 implants were 5mm in diameter and 8,10,11.5,13mm in length (10%) (Table 1), (Figure 1).