Conservative therapy versus arthrocentesis for the treatment of symptomatic disk displacement without reduction: a prospective randomized controlled study.

OBJECTIVE: Disk displacement without reduction (DDwoR) results in pain and limited mouth opening, with negative impact on daily function. Noninvasive interventions are the standard primary treatment for DDwoR. This study compared the clinical outcomes from noninvasive (conservative) and minimally invasive (arthrocentesis) treatments in patients with DDwoR. STUDY DESIGN: Twenty-four patients with clinically diagnosed symptomatic closed lock were randomized to noninvasive (information, self-exercise, occlusal splints) intervention group and a minimally invasive (information, arthrocentesis with lavage, manipulation, postoperative self-exercise) intervention group. Maximal mouth opening (MMO) and pain (visual analogue scale [VAS]) were measured at baseline and at 3, 6, and 12 months after treatment. RESULTS: Both groups showed a successful outcome after 1 year. In the noninvasive group, the (mean ± SD) MMO value was 46.3 ± 7.2 mm, and the VAS score was 11 ± 17.1 in; and in the minimally invasive group, the MMO value was 42.7 ± 6.1 mm, and the VAS score was 10 ± 6.3. There were no significant differences between the 2 groups. Interestingly, a subgroup of patients who recovered spontaneously before treatment start had significantly higher MMO values at baseline (P = .028). CONCLUSIONS: Outcomes with the 2 interventions (noninvasive and minimally invasive) are similar, and patients with a higher baseline MMO are more likely to experience spontaneous recovery.

One-year results of a clinical and radiological prospective multicenter study on NEOSS® dental implants.

BACKGROUND: NEOSS® (Neoss Ltd., Harrogate, UK) dental implant system was introduced on the clinical arena in 2003. It is important that novel implant systems are systematically evaluated in a multicenter setting. PURPOSE: The aim of this study was to follow a large number of consecutively treated patients, with NEOSS dental implant system, both clinically and radiographically. The current report constitutes the 1-year data of a planned 5-year study. MATERIALS AND METHODS: The study included a total of 177 patients treated with 590 NEOSS implants at 13 clinics in Sweden. The material was composed of 72 males and 105 females treated for single, partial, and total edentulism. Clinical, radiographic, and subjective evaluations were performed. RESULTS: Out of 590 implants, 13 early failures have been reported, corresponding to a 1-year cumulative survival rate (CSR) of 97.8%. Evaluation of function and esthetics at the 1-year visit resulted in 100% success for function and 98% success for the esthetic outcome. The mean marginal bone loss was 0.6 mm (SD 1.1) after 1 year in clinical function. No adverse effects of the NEOSS dental implants were reported, and complications were few and similar to those reported for implant treatment in general. CONCLUSION: The CSR in the present study was 97.8%. No adverse effects of the NEOSS implants were reported, and complications during the study period were few and similar to those reported to for other well-documented implants system. Based on the present data, we conclude that NEOSS dental implant is a safe and predictable implant system. However, the high number of dropouts in the radiological evaluation must be considered when interpreting the data.

Morbidity after chin bone harvesting--a retrospective long-term follow-up study.

BACKGROUND: Resorption of the alveolar bone after tooth extraction may result in insufficient bone volume for implant placement. Augmentation of the resorbed site using autogenous bone grafts harvested from the maxillofacial region, for example, the chin, is a common method; however, it also involves donor site morbidity. Chin graft morbidity involves impaired sensibility in the frontal teeth, the gingival, and skin postoperatively. MATERIALS AND METHODS: A group of 60 patients with partial edentulism in the maxilla and insufficient bone volume for implant therapy were augmented with bone grafts from the mandibular symphysis. The grafting procedure was performed between 1991 and 2001 with a follow-up period of 1 year after surgery. Postoperative sensibility of the lip, teeth, and gingiva was registered. Forty-six patients (18 women and 28 men) also participated in a long-term follow-up study. The mean age was 49 years (range 23-81 years) and the mean follow-up time was 7.5 years (range 4-14 years). The donor site was evaluated in four parts: a standardized clinical examination, radiographic examination and measurements, a mail-in questionnaire, and a survey of the medical records regarding complications and graft size. In the donor site, both hard tissue (mandibular symphysis and teeth) and soft tissue (ie, lower lip, infralabial area, and chin) were evaluated. A questionnaire was also answered by 38 of 46 patients. RESULTS: In the long-term follow-up, impaired tactility and sensitivity of the soft tissues were registered in 7.6%. Adjacent teeth (incisors, canines, first and second premolar) (n = 418), showed increased lamina dura in seven cases (1.7%) and four teeth had apical pathology (1.0%). The donor site (n = 45) showed good remineralization in 42 patients (93.3%), and 28 patients (62.2%) had a noticeable concavity radiologically. The questionnaires from 38 patients (answer frequency 82.3%) rated high satisfaction with the grafting and implant treatment. CONCLUSIONS: This study indicates that long-term follow-up of the chin graft donor site shows some postoperative morbidity. The most frequent disturbance was impaired sensibility in the soft tissues of the chin. The lower lip and teeth showed fewer disturbances. The rate of subjective symptoms was higher than the clinical findings but did, in general, not affect the patient in daily life. At radiographic examination, bone healing after chin graft harvesting did not regenerate to the preoperative level. The donor site showed good remineralization but left a radiologic concavity in the majority of cases.

Clinical evaluation of the zygoma implant: 3-year follow-up at 16 clinics.

PURPOSE: The purpose of this clinical investigation was to evaluate the treatment outcome with zygoma implants with regard to implant survival, patient satisfaction, and function of prosthesis replacement after 3 years. PATIENTS AND METHODS: The treatment outcome of 76 patients treated with 145 zygoma fixtures at 16 centers was evaluated with regard to implant survival. Status of peri-implant mucosa and amount of plaque were registered annually. Patients' and dentists' evaluations of the functional and esthetic outcome of the treatment were assessed at delivery of prosthesis and thereafter at each follow-up visit. RESULTS: Sixty of 76 patients were followed for 3 years after prosthetic delivery. Five of 145 placed zygoma implants failed during the course of the study resulting in an overall implant survival rate of 96.3%. At the 3-year follow-up, 75% of the implants sites were registered with normal peri-implant mucosa and 68% with no visible plaque. The patients were fully satisfied with the esthetic and functional outcome of the treatment in 86% and 71%, respectively, at the 3-year follow-up visit. All reported data from dentists scored from acceptable to excellent. CONCLUSION: The multicenter study showed a high predictability of the zygoma implant-supported rehabilitation.

One-year results of a prospective multicenter study on Brånemark System implants with a TiUnite surface.

BACKGROUND: A moderately rough surface implant (TiUnite, Nobel Biocare AB, Göteborg, Sweden) was introduced in 2000. Laboratory studies and some clinical studies have demonstrated excellent bone response in the early healing phase. PURPOSE: The aim of this prospective multicenter study was to follow a large number of consecutively treated patients using Brånemark System implants with the TiUnite surface. The current report constitutes the 1-year data of a planned 3-year study. MATERIALS AND METHODS: Originally, the study comprised 43 surgeons from 22 centers in Sweden, Norway, and Finland. Five centers were excluded from the study because of poor compliance. Thus, 187 patients treated with 478 TiUnite implants were followed during 1 year of function. The majority of implants were inserted in maxillae (357 implants), and 78 of the implant sites were assigned the quality 4 figure. Radiographic evaluations were performed. RESULTS: Five implants were lost up to and including the 1-year follow-up, revealing implant cumulative survival rates of 98.6% and 100% for maxillae and mandibles, respectively. Three implants failed in quality 4 bone (3.8%). The mean marginal bone resorption at the end of the study period was 1.4 mm. The number of withdrawals of patients during the first year was high (19.3%). CONCLUSION: The present investigation showed a high implant cumulative survival rate of 98.9%. Values of marginal bone resorption were within normal ranges. No adverse effects of the TiUnite surface were reported, and complications during the study period were few and similar to those reported for the turned implant surface. However, the high number of excluded patients and the relatively high number of withdrawals must be observed and considered when interpreting data.

A clinical evaluation of the Zygoma fixture: one year of follow-up at 16 clinics.

PURPOSE: To evaluate treatment outcome with Zygoma fixtures (Nobel Biocare, Göteborg, Sweden) with regard to fixture survival, patient satisfaction, and function of prosthesis replacement. MATERIALS AND METHODS: The treatment outcome of 76 patients treated with 145 Zygoma fixtures at 16 centers was evaluated. Patient's and dentist's evaluations of the functional and aesthetic outcome of the treatment were assessed at delivery of prosthesis and at the 1-year follow-up visit. At the 1-year follow-up visit, the status of the peri-implant mucosa around the abutments and the amount of plaque were registered. RESULTS: Sixty-six of the 76 patients, with 124 Zygoma fixtures supporting the prosthetic restorations, were evaluated at the 1-year follow-up. The overall survival rate for the Zygoma fixtures was 97.9% after 1-year of follow-up. Eighty percent of the patients were fully satisfied with both aesthetic and functional outcome at the time of prosthetic insertion and at the 1-year follow-up. All reported data from the dentists, with the exception of one restoration with several abutment screw loosenings, scored from acceptable to excellent for the aesthetic and functional outcome of the treatment. The status of peri-implant mucosa was recorded as normal in approximately 60% of the sites. Plaque, when present, was more often detected on the palatal surfaces compared with the buccal surfaces. CONCLUSION: This 1-year follow-up of Zygoma fixtures has shown good results with an acceptable number of minor complications and a majority of satisfied patients.

One-year prospective three-center study comparing the outcome of a "soft bone implant" (prototype Mk IV) and the standard Brånemark implant.

BACKGROUND: Oral implant treatment ad modum Brånemark has been used for decades in the rehabilitation of edentate and partially dentate patients. Posterior jaw regions frequently exhibit bone of poor texture, and it is often difficult to obtain primary stability. Thus, it may prove beneficial to deviate from the original protocol and to use implants with a modified design, for example, with a slightly tapered geometry. PURPOSE: The purpose of the investigation was to compare the early behavior of a modified (prototype Mk IV, Brånemark System, Nobel Biocare AB, Gothenburg, Sweden; test) implant with that of the standard Brånemark implant (control) in regions of mainly type 4 bone. MATERIALS AND METHODS: Three Swedish centers participated, and a total of 44 patients were treated with oral implants for 39 maxillas and 5 mandibles. The study focused on the most distal right and left implant sites (88 implants), which were randomized to receive either a test or a control implant. Various parameters were recorded, such as registered insertion torque (OsseoCare), Nobel Biocare AB), wobbling during insertion, primary and secondary stability (as measured with resonance frequency), and marginal bone loss. The implants were followed up for 1 year. RESULTS: The test implant more frequently required a higher insertion torque and showed a significantly higher primary stability than the control implant. This difference in stability leveled out over time, and test and control implants exhibited similar secondary stability at abutment operation and at the 1-year visit. Wobbling during insertion was rarely recorded for either of the implant designs. The 1-year cumulative success rate was 93.1% for test implants and 88.4% for control implants. CONCLUSIONS: The modified implant design resulted in an increased primary stability, which may be important when placing implants in jaw regions of type 4 bone. However, independent of the achieved primary stability, successful implants tended to approach similar secondary stability in the two designs tested.

Histologic evaluation of bone response to oxidized and turned titanium micro-implants in human jawbone.

PURPOSE: To evaluate the human bone tissue response to 2 surfaces (oxidized or turned) on commercially available titanium implants. MATERIALS AND METHODS: Screw-type turned (control) and oxidized (test) micro-implants were manufactured in the same manner as commercially available turned and oxidized (TiUnite, Brånemark System) implants. The thickness of the oxide layer of the test implants was on average 10 microm, corresponding to the oxide thickness of the apical part of the TiUnite implant. Twenty patients received 1 test and 1 control micro-implant each during implant surgery. Before placement, the surface topography of the implants was characterized with an optical confocal laser profilometer. After a mean healing period of 6.6 months in the maxilla and 3.5 months in the mandible, the micro-implants and surrounding tissue were removed with a trephine bur. Histologic sections were produced, and the specimens were analyzed histomorphometrically. RESULTS: Surface roughness and enlargement were greater for the oxidized implants than for the turned implants. All micro-implants, except for 2 controls, were found to be clinically stable at the time of retrieval. Histomorphometric evaluation demonstrated significantly higher bone-to-implant contact for the oxidized implants, whether placed in the maxilla or in the mandible. Significantly more bone was found inside the threaded area for the oxidized implants placed in the mandible and maxilla, but there was no difference between implants with regard to position (maxilla or mandible). DISCUSSION: The stronger bone response to the oxidized implants may have contributed to the fact that 2 control implants but no test implants were lost. The reason for these findings may depend on one or multiple differences of the surfaces between test and control implants: (1) the thicker oxide layer itself, (2) increased surface roughness, (3) different surface morphology in terms of porosity, or (4) change in crystal structure. CONCLUSION: The present histologic study in human jawbone demonstrated a significantly higher bone response for anodic oxidized titanium implants than for implants with a turned surface.

Mk III: a third generation of the self-tapping Brånemark System implant, including the new Stargrip internal grip design. A 1-year prospective four-center study.

BACKGROUND: Many prospective studies have shown predictable long-term results of the Brånemark System (Nobel Biocare AB, Gothenburg, Sweden) turned-surface implants in totally edentulous, partially edentulous, and single cases. The Mk III self-tapping implant was introduced by Nobel Biocare in 1999 as part of a new implant generation that improved on the Mk II self-tapping implant that had been introduced in 1992. A new implant design should always be evaluated, preferably in prospective multicenter studies. PURPOSE: The aim of the present prospective multicenter study was to evaluate the short-term success rate of the Brånemark Mk III machined- and turned-surface self-tapping implant and to evaluate the clinical handling of the new Stargrip (Nobel Biocare AB) internal grip design. MATERIALS AND METHODS: The open prospective 1-year multicenter study was performed at four clinics. Sixty-four patients (38 females, 26 males) with a mean age of 51 years (range, 16 to 80 years) were included. Seventeen of the patients were totally edentulous, 26 were partially edentulous, and 21 had single-tooth losses. In total, 194 Mk III implants were inserted, 89 in the maxillas and 105 in the mandibles. RESULTS: Fifty-eight patients were observed for 1 year after prosthetic loading. Three of 194 implants were lost, corresponding to a cumulative success rate of 98.4% after 1 year, 100% for maxillary implants and 97.1% for mandibular implants. The implant driver carried the implants reliably in 99.5% of all treated patients. Sixty-two patients received the planned prosthetic reconstruction. All but one prosthetic reconstruction survived after 1 year of loading. The mean marginal bone resorption, analyzed from radiographs of 143 implants, was 1.15 mm (standard deviation [SD], 1.09 mm) from the second-stage surgery to the 1-year follow-up. CONCLUSION: The 1-year success rate of the Mk III implant was high, and the clinical handling of the internal grip design (Stargrip) improved the surgical technique and was well appreciated by both surgeons and assisting staff.