Relationship between Implant Length and Implant Stability of Single-Implant Restorations: A 12-Month Follow-Up Clinical Study.

Background and Objectives: Implant stability in vivo is contingent on multiple factors, such as bone structure, instrument positioning and implant surface modifications, implant diameter, and implant length. Resonance-frequency analysis is considered a non-invasive, reliable, predictable, and objective method by which to evaluate implant stability, due to its correlation with bone-to-implant contact. The purpose of this study was to evaluate the effect of implant length on the primary and secondary stability of single-implant crown rehabilitations, as measured by resonance-frequency analysis at different times. Materials and Methods: Implants of 10 and 11.5 mm were placed, and the resonance frequency was measured at the time of surgery (T0), as well as at 3 (T1), 6 (T2), and 12 (T3) months post-surgery. Results: A total of 559 implants were placed in 195 patients. Significant differences were observed when comparing the implant stability quotient (ISQ) values at T1, with values for 10-mm implants being greater than those for 11.5-mm implants (p = 0.035). These differences were also observed when comparing ISQ values for buccal and lingual areas. At T0, T2, and T3, no significant differences in ISQ values were observed. The use of 10-mm implants in the anterior maxilla yielded significantly greater values at T0 (p = 0.018) and T1 (p = 0.031) when compared with 11.5-mm implants. Significant differences in measurements were observed only for buccal areas (p = 0.005; p = 0.018). When comparing the sample lengths and sex, women with 11.5-mm implants showed significantly lower results than those with 10-mm implants (p < 0.001). Conclusions: There is a direct relationship between implants of a smaller length and greater ISQ values, with this relationship being most evident in the maxilla and in women.

Validation of Therapeutic Anatomy-Oriented Classification in Endosseous Dental Implant Treatment: A Pilot Study.

BACKGROUND: The purpose of the study was to validate a newly proposed therapeutic anatomically based clinical and radiological classification for dental implant treatment. METHODS: Eighty-one patients with at least 1 edentulous jaw segment (EJS) from 2 dental clinics were included in this study. Both clinical and radiological parameters were assessed in aesthetic and nonaesthetic zones. The data were then compared at preoperative, intraoperative, and postoperative (subdivided into early and late stage) study stages. RESULTS: Based on the hard and soft tissue support, EJSs were divided into 3 types. The outcomes were then validated at preoperative, intraoperative, and early postoperative stages. Data were then analyzed using paired sample t test and the Wilcoxon signed ranks test. No statistically significant difference (P > 0.05) was identified between any the measurements. CONCLUSIONS: The proposed therapeutic anatomically based clinical and radiological classification for the dental implant treatment seems to be reproducible, objective, and helpful in planning dental implant treatment. Future studies with a larger sample size are needed to further validate the outcome obtained in this pilot study.

Dental devices; reclassification of blade-form endosseous dental implant. Final order.

The Food and Drug Administration (FDA) is issuing a final order to reclassify the blade-form endosseous dental implant, a preamendments class III device, into class II (special controls). On its own initiative, based on new information, FDA is revising the classification of blade-form endosseous dental implants.

A correlation between bone (B), insertion torque (IT), and implant stability (S): BITS score.

STATEMENT OF PROBLEM: Although criteria for assessing bone quality have been reported, an overall score that correlates bone quality with the primary stability and secondary stability of implants is not yet available. PURPOSE: The purpose of this article was to propose a scoring index that will establish a correlation among the bone density values from computed tomography, maximum insertion torque values, and resonance frequency analysis in different phases of implant treatment. MATERIAL AND METHODS: In this study, 60 implant sites were evaluated to assess bone density (Hounsfield units), insertion torque values (Ncm), and primary stability and secondary stability (implant stability quotient values obtained by using resonance frequency analysis). On the basis of computed tomography data, the bone was classified as D1 to D4. The insertion torque was noted and classified into 2 groups, A and B. The implant stability quotient values obtained from resonance frequency analysis depicting primary stability and secondary stability were classified into 5 groups. The primary score noted was a result of the values obtained for the 3 parameters at the time of implant placement. The secondary score was obtained by considering the values of the bone density and resonance frequency analysis recorded at different time intervals. RESULTS: Bone densities of D2, D3, and D4 were noted, dividing the bone type into 3 groups. The maximum torque noted in the study was 40 Ncm. The difference between various insertion torque values and bone types was found to be statistically nonsignificant. Higher mean implant stability quotient values were obtained for primary and secondary stability for the D2 bone than for D3 and D4 bone. When analyzed according to the time of insertion, the mean values increased at second stage surgery in all bone types. The difference in mean values among all bone types was found to be statistically significant (P<.001). A comparison of primary and secondary implant stability quotient values in all bone types did not find any statistical significance (P=.780). A score was recorded at the time of implant placement and at the time of second stage surgery, and the prosthetic treatment was planned accordingly. CONCLUSIONS: The score highlights the importance of considering the association of bone quality, insertion torque values, and stability as denoted by implant stability quotient throughout treatment. Based on the variation in the score noted at recall visits, alterations in the treatment plan can be made with respect to the healing period and prosthetic design.

Timing of implant placement: planning and procedures for predictable clinical and aesthetic outcomes.

The placement of dental implants is dependent on a number of factors relating to both the patient and the site in which implant placement is contemplated. Additionally, there has been a general trend towards immediacy in implant therapy. This paper considers case selection and clinical decision-making and treatment guidelines in cases where immediate implant placement is contemplated. Treatment alternatives, including site preservation, early and delayed implant placement are also discussed.

A proposed classification for zygomatic implant patient based on the zygoma anatomy guided approach (ZAGA): a cross-sectional survey.

PURPOSE: The aim of the present cross-sectional study was to propose a classification system based on a cross-sectional survey of zygomatic implant cases. MATERIALS AND METHODS: Cone beam computerised tomography (CBCT) postoperative images and clinical intra-surgery photographs of 200 sites corresponding to 100 patients, treated with a total of 198 zygomatic implants in the maxilla according to an anatomy-driven prosthetic approach, were reviewed with regard to anatomy and pathway of the zygomatic implant body. The patients were consecutively selected independently of the type of surgery performed, with the unique requirement of a post-surgical CBCT performed at the moment of selection. Of special interest was the morphology of the lateral sinus wall, residual alveolar crest and the zygomatic buttress. An attempt was made to divide the patients into groups, describing typical anatomies and implant pathways. RESULTS: Five basic skeletal forms of the zygomatic buttress-alveolar crest complex and subsequent implant pathways could be identified in a sample of 100 patients. Out of them, 62% were female and 38% male, with ages varying between 36 and 83 years (mean age 59.6, SD: 9.67). The five groups were classified as ZAGA 0 to 4 representing 15%, 49%, 20.5%, 9% and 6.5% of the studied sites, respectively. Intra-individual anatomical differences affecting the zygomatic buttress-alveolar crest complex was also found in 58% of the patients. CONCLUSIONS: Five typical anatomical and implant pathway situations could be identified. A classification system comprising five groups named ZAGA 0 to 4 is proposed. Anatomical intra-individual differences were also found in the 58% of the studied population. It is believed that the proposed classification system is useful for categorising zygomatic implant cases for therapy planning and for scientific follow-up purposes.

Treatment planning implant dentistry with a 2-mm twist drill.

Drilling with a 2-mm twist drill is the first time a clinician can assess variations in bone density for the length of bone where an implant will be placed. Evaluation of bone density is critically important with respect to making decisions regarding depth and width of an osteotomy, undersizing the drilling sequence, submerging vs not submerging an implant, supracrestal vs subcrestal implant placement, selecting a tapered vs nontapered implant, countersinking, platform switching, immediate loading, healing time, etc. This article addresses how information acquired with a 2-mm twist drill can affect treatment planning. In particular, this article underscores that the clinician must be prepared to alter drilling protocols based on tactile feedback from a 2-mm twist drill.

Endoimplantology: part 2, surgical classifications.

The morphic classification developed is a silver lining enabling projection, as well as retraction, for complex surgical approaches where ultimate decisions may have to be taken extemporaneously as the surgical case develops. From both a consent form and clinical standpoint, this approach brings clarity to the patient avoiding surprises and disappointment. It also guides the practitioner whose best clinician intention may not alway materialize and guaranty the best and most reasonable possible achievement.

The osteotome technique: a classification for technique approach and clinical case reports.

A classification system for Summers' osteotome technique was proposed, categorizing the technique into 4 classes. Additional descriptions are included to further define different approaches. The classification for the technique approach will assist future communication among clinicians and researchers. This article presents representative clinical cases to aid the clinician in applying the classification for the technique approach.

A proposal for universal nomenclature in implant prosthodontics.

Attempts have been made at formulating standardized nomenclature for implantology. Although these classification systems have advanced the concept of universal nomenclature in implantology, they can be improved upon. Most of them present terms in glossary form, which can limit their applicability. Others deviate significantly from accepted basic terminology and can be foreign or ambiguous to the average clinician. This article outlines the semiotic approach to language formulation, discusses slight changes to accepted conventional prosthodontic terminology to better encompass implant dentistry, and introduces the shortform and support-retention-connection-prosthesis classification systems.

Soft tissue closure over immediate implants: classification and review of surgical techniques.

Despite the different opinions regarding the success of implants and guided bone regeneration membranes, with and without establishing primary wound closure at the time of surgical placement, primary closure logically seems to be the ideal surgical protocol. It prevents bacterial invasion to the wound and prevents wound disruption. In immediate implantation, lack of keratinized tissue available to achieve this surgical goal is a problem. Various surgical techniques are described to overcome this surgical difficulty, each having its advantages and drawbacks. Sound clinical judgment must be exercised when selecting a method, because it will influence the treatment result both esthetically and functionally by altering adjacent soft tissue and bony topography.

Spontaneous early exposure of submerged endosseous implants resulting in crestal bone loss: a clinical evaluation between stage I and stage II surgery.

Spontaneous early exposure of submerged implants during the osseointegration healing phase may be a harmful factor that results in early crestal bone loss around the implants. The objective of this study was to assess the effect of spontaneous early exposure on crestal bone loss around submerged implants, with special attention given to the relationship between the degree of exposure and the amount of peri-implant bone loss. Crestal bone level relative to the shoulder of the implant was measured at the time of placement and at the time of exposure 4 to 5 months later. During the period between stage I and stage II surgery, implant sites were observed, and each implant site in which spontaneous early exposure was detected was recorded. Perforations were classified according to the degree of implant exposure from Class 0 (no perforation) to Class IV (complete exposure). Measurements from 206 implants in 64 patients produced 85 groups valid for statistical comparison; each of these contained at least 2 lesions of different types. There was a statistically significant difference between bone loss associated with intact mucosa (Class 0) and Class I, Class II, and Class III lesions, and between Class I and II lesions. There were no significant differences between Class I and III and between Class II and III. In Class II and III lesions, there was more bone loss associated with the buccal aspect of the implants. Of the 115 perforated sites, 10 were associated with bone loss exceeding 2 mm, 2 presented 3 to 4 mm bone loss, 1 showed more than 4 mm, and 1 displayed more than 5 mm. In view of the clinical implications that spontaneous early exposure may have on the success of osseointegration, prematurely partially exposed implants should be exposed as soon as possible after the perforation is observed.

Carga inmediata sobre implantes: una posibilidad protésica / Immediate implant loading: a prosthetic possibility

El Dr. Branemark introdujo la oseointegración como principio de la terapia con implantes endoóseos. Sus trabajos científicos a largo plazo permitieron establecer su éxito a largo plazo. El protocolo quirúrgico y protésico determinó factores esenciales de trabajo para obtener oseointegración, destacándose entre ellos la realización del implante de dos fases quirúrgicas con un intervalo de tres a seis meses, sin carga protésica. Las circunstancias que permitieron el desarrollo del protocolo inicial fueron muy diferentes a las actuales. Con el tiempo se han modificado algunso principios propios del protocolo original. Por medio de una revisión bibliográfica y el reporte de un caso, se pretende mostrar cómo se ha llegado a establecer la carga protésica inmediata como una posiblidad protésica, sin poner en riesgo la oseointegración del implante

Clinical complications of osseointegrated implants.

STATEMENT OF PROBLEM: There is no comprehensive review of the literature that identifies the complications reported in clinical dental implant studies. PURPOSE: This article attempted to determine the types of complications that have been reported and to provide data regarding their frequency. METHODS: All available clinical studies from 1981 to 1997, published in English or with English abstract, that presented success/failure data regarding implant treatment were evaluated to determine the types of reported complications and to quantify implant loss as it relates to type of prosthesis, arch, time, implant length, and bone quality. RESULTS: Greater implant loss occurred with overdentures than with other types of prostheses. There was greater loss in the maxilla than mandible with fixed complete dentures and overdentures, whereas little arch difference was noted with fixed partial dentures. Implant loss increased with short implants and poor bone quality. The time of implant loss (preprosthetic vs postprosthetic) varied with type of prosthesis. Surgical complications included neurosensory disturbance, hematoma, mandibular fracture, hemorrhage, and tooth devitalization. Initial and long-term marginal bone changes were identified. Peri-implant soft tissue complications included dehiscence, fistulas, and gingival inflammation/proliferation. Mechanical complications were screw loosening/fracture, implant fractures, framework, resin base and veneering material fractures, opposing prosthesis fractures, and overdenture mechanical retention problems. Some studies also presented phonetic and esthetic complications. CONCLUSIONS: Although the literature presents considerable information on implant complications, variations in study design and reporting procedures limited the available data and therefore precluded proper analysis of certain complications.

Clinical experiences with dental implants.

The clinical utilization of dental implants has accelerated in recent years, and new applications continue to emerge. Concomitantly, alternative implant systems have introduced conceptually different approaches to treatment using altered protocols. The purpose of this paper is to address some of the background issues pertinent to the long-term success, survival, safety, and effectiveness of these devices. The requirements for clinical acceptance of implants are controlled initially by regulatory bodies; however, the dentist eventually must make a decision on which type of implant should be used in clinical practice. This clinical decision-making process should involve the strategy of using an evidence-based approach to ensure quality of care and reduction of liability for negligent care. This is particularly the case when treatment is undertaken in identified high-risk categories. While short- to medium-term data have been accumulated on the success rates of several implant systems, it is apparent that long-term data comparing and contrasting the various advantages and disadvantages of different systems do not exist, and adequate criteria applicable to the collective clinical experience need to be defined. Expanding areas of application are dependent on continuous improvements in implant hardware, surgical protocol development, and rationalized osteopromotive and site installation augmentation technology. Many treatment endeavors are still largely at the pilot study level of development, and long-term prospective clinical trials on large numbers of patients are required to document results adequately and to elucidate the most likely productive areas for future investigation.