Faculty Bibliography

Lack of adequate support (tooth/soft tissue) results in displacement of bilateral and unilateral distal extension removable partial dentures. Placement of implants is one option for managing this problem. The aim of this report is to describe fabrication of a mandibular removable partial denture supported by 2 unilateral distal implants with locater attachments. The patient was a 70-year-old man who was missing the right mandibular premolars and molars. After an uneventful 3-month healing period, the locater abutments were tightened on the implants. At a recall appointment 18 months later, neither of the implants had been lost, but some marginal bone loss (mean 0.3 mm, standard deviation 0.1 mm) was noted. The patient reported no displacement of the distal extension removable partial denture. This case report suggests that distal implants may help to prevent displacement of distal extension removable partial dentures, and may be especially suitable for patients who cannot afford implant-supported fixed dental prostheses.

AIM: The aim of this case report is to describe the replacement of a maxillary peg-shaped lateral incisor with the placement of an immediate implant and a provisional restoration following a minimally invasive extraction to preserve anterior esthetics. BACKGROUND: Extraction sites in the anterior maxilla can present restorative challenges with regard to esthetics. Resistance to wearing a temporary removable partial denture during healing makes immediate implant therapy an appealing alternative to patients. Implant placement into fresh extraction sockets using no flap elevation has recently become more popular due to some advantages including less bleeding, swelling, and the preservation of existing soft tissue contours. CASE REPORT: A 20-year-old woman with a peg-shaped maxillary left lateral incisor was treated using an implant placed into the fresh extraction socket using a flapless approach and immediate provisional crown fabrication. Flapless implant placement helps to preserve site morphology by protecting and supporting existing hard and soft tissues while minimizing surgical trauma to the adjacent tissues. Using a previously fabricated acrylic index, a provisional acrylic crown was fabricated on the adjusted temporary abutment and delivered to the patient the same day during the extraction visit. SUMMARY: This report describes the diagnosis and treatment of an over-prepared peg-shaped maxillary left lateral incisor associated with multiple crown decementations. The tooth was extracted without flap elevation and an implant was inserted immediately using flapless surgery and placement of an immediate provisional single crown. CLINICAL SIGNIFICANCE: Flapless implant insertion into fresh extraction sockets and placement of immediate provisional crowns in cases involving the maxillary anterior region represent a viable treatment option in appropriate clinical situations where esthetics are a high priority. The strategy preserves optimum gingival contours and papillary height may be a viable option compared to fixed partial dentures.

BACKGROUND: The quality of bone is an important factor in the successful implant treatment, and it is evident that higher implant failure is more likely in poor quality of bone. The primary stability of oral implants related to resistance to micromotion during healing is influenced by bone quality, surgical technique, and implant design. PURPOSES: The aims of this biomechanical study were to explore the effect of bone quality on initial intraosseous stability of implants, and to determine the correlations between the bone quality and implant stability parameters. MATERIALS AND METHODS: Twenty-four implants (Neoss Ltd., Molnlycke, Sweden) were placed into anterior and posterior regions of three human cadaver mandibles. The bone densities of implant recipient sites were preoperatively determined using computerized tomography (CT) in Hounsfield unit (HU). The maximum insertion torque values were recorded, and primary implant stability measurements were noninvasively performed by means of resonance frequency analysis (RFA). RESULTS: The bone density values ranged from -267 HU to 553 HU. It was found that mean bone density, insertion torque, and RFA values were 113 +/- 270 HU, 41.9 +/- 5 Ncm, and 70 +/- 7 implant stability quotient (ISQ), respectively. Statistically significant correlations were found between bone density and insertion torque values (r = 0.690, p < .001); bone density and ISQ values (r = 0.557, p < .05); and insertion torque and ISQ values (r = 0.853, p < .001). CONCLUSION: CT is a useful tool to assess bone quantity and quality in implant recipient sites, and bone density has a prevailing effect on implant stability at placement.

AIM: The aim of this case report is to present a description of bone mapping as an alternative method to determine the dimensions of bone prior to placement of a flapless implant and an immediate provisional crown. BACKGROUND: The use of a temporary removable partial denture (RPD) or "flipper" during healing following an extraction is not acceptable for some highly demanding patients. As a result, flapless implant placement is gaining popularity because it offers some advantages such as less bleeding, less swelling, and the protection of soft tissue contours. CASE REPORT: A 65-year-old woman missing a maxillary left lateral incisor was treated using flapless implant placement and an immediate provisional acrylic crown. Under local anesthesia, the bone anatomy was mapped by inserting a standard periodontal probe in the gingiva. By using the recorded measurements, the thickness of soft tissue was removed from the cast. A surgical guide based on this adjusted model was fabricated prior to surgery. The guide was seated on the teeth when actual surgery was performed to facilitate bone drilling and then the implant was placed. Utilizing the previously fabricated acrylic tooth index, the temporary acrylic crown was fabricated on the adjusted temporary metal abutment and delivered to the patient the same day. SUMMARY: In this case report the missing maxillary left lateral tooth was restored using flapless implant placement and an immediate provisional single crown. The dimension of the bone at the implant recipient area was determined by an alternative bone mapping method. CLINICAL SIGNIFICANCE: This case report suggests the use of flapless implant placement using the bone mapping method and immediate provisional crowns for single crowns when esthetics are a high priority and preserving ideal soft tissue contours and papillary heights are critical.

Some patients are not satisfied with a hybrid prosthesis for esthetic reasons, as it has screw holes and leaves a space between it and the gingiva. This article presents a case in which an implant-supported mandibular cemented prosthesis was fabricated as an alternative to screw-retained hybrid prostheses. A 77-year-old edentulous man was treated with five non-submerged implants in the anterior mandible. Two different prostheses (an implant-supported mandibular cemented prosthesis and a maxillary complete denture) were delivered to the patient one month after surgery. Resonance frequency analysis measurements were performed and marginal bone levels were evaluated at the time of surgery and again after 12, 24, and 36 months. Over this three-year period, no implants were lost and all five showed less than 1 mm of marginal bone loss.

BACKGROUND: Clinical studies show promising outcomes with implants inserted at the time of extraction. However, this often results in an initial bone defect at the marginal region which preferably should heal for an optimal function. Therefore, monitoring of these implants is vital. PURPOSES: The aims of this study were to determine the initial stability of implants placed into fresh extraction sockets, and to explore the correlations between the peri-implant bone levels and implant stability parameters. MATERIALS AND METHODS: Six human cadaver mandibles including all natural teeth were selected for this study. All natural teeth were gently extracted, and 84 implants were immediately placed into fresh extraction sockets with five different implant depths. The maximum insertion torque values were recorded, and primary implant stability measurements were performed by means of resonance frequency analysis (RFA). The vertical distance between implant/abutment junction and the first bone-implant contact was recorded using a periodontal probe. RESULTS: It was found that the insertion torque and RFA were 28.9 +/- 7 Ncm and 65.6 +/- 9 implant stability quotient (ISQ), respectively, for 420 measurements from all 84 implants. Statistically significant correlation was found between insertion torque and ISQ values (r = 0.86; p < .001) for all implants. Both insertion torque and ISQ values dramatically decreased when the amount of peri-implant vertical bone defect increased. CONCLUSION: The results of this study demonstrated a linear relationship between peri-implant vertical bone defect depth and RFA value. It is proposed that the RFA method is sensitive to detect changes of the marginal bone level and may be used to monitor healing of peri-implant bone defects.

PURPOSE: Presurgical planning is essential to achieve esthetic and functional implants. The goal of this clinical study was to determine the angular and linear deviations at the implant neck and apex between planned and placed implants using stereolithographic (SLA) surgical guides. PATIENTS AND METHODS: A total of 110 implants were placed using SLA surgical guides generated from computed tomography (CT). All patients used the radiographic templates during CT scanning. After obtaining 3-dimensional CT scans, each implant insertion was simulated on the CT images. SLA surgical guides using a rapid prototyping method including a laser beam were used during implant insertion. A new CT scan was made for each patient after implant insertion. Special software was used to match images of the planned and placed implants, and their positions and axes were compared. RESULTS: The mean angular deviation of all placed implants was 4.1 degrees+/-2.3 degrees, whereas mean linear deviation was 1.11+/-0.7 mm at the implant neck and 1.41+/-0.9 mm at the implant apex compared with the planned implants. The angular deviations of the placed implants compared with the planned implants were 2.91 degrees+/-1.3 degrees, 4.63 degrees+/-2.6 degrees, and 4.51 degrees+/-2.1 degrees for the tooth-supported, bone-supported, and mucosa-supported SLA surgical guides, respectively. CONCLUSION: The results of this study suggested that stereolithographic surgical guides using CT data may be reliable in implant placement, and tooth-supported SLA surgical guides were more accurate than bone- or mucosa-supported SLA surgical guides.

In areas where esthetics is paramount, healing should be adequately completed around the implant healing abutment to stabilize the gingival margin before crown fabrication. This article describes a technique to increase the height of the healing abutment with laser welding when an implant is placed deep with thick overlying soft tissue.

BACKGROUND: The primary stability of dental implants associated with resistance to micromotion during healing is affected by surgical technique and implant design, which are important especially in the soft bone, where implant failures are more likely. PURPOSES: This study was designed to compare the parameters associated with implant insertion using two different methods of enhancing implant primary stability and to identify any relationship between these parameters at implant insertion. MATERIALS AND METHODS: A total of 60 implants were placed in the maxillary posterior regions of 22 patients. The bone densities at the implant sites were recorded using a computerized tomography machine in Hounsfield unit (HU). The maximum insertion torque data were recorded with the Osseocare (Nobel Biocare AB, Goteborg, Sweden) equipment, while resonance frequency analysis (RFA) measurements were taken using an Osstell (Integration Diagnostics AB, Goteborg, Sweden) machine at implant surgery. Comparisons including HU, Ncm, and implant stability quotient were made between two control groups (C1 and C2), and corresponding four test groups (T1-T4) using thinner drills to enhance primary implant stability. RESULTS: Two implants were lost, meaning an overall implant survival rate of 96.6% after 3 +/- 1 years. When compared to control groups, significantly higher mean maximum insertion torque and RFA values were found for corresponding test groups. In addition, strong correlations were observed between the bone density and insertion torque, and implant stability values at implant placement. CONCLUSION: The results of this study suggest that using thinner drills for implant placement in the maxillary posterior region where bone quality is poor may improve the primary implant stability, which helps clinicians to obtain higher implant survival rates.

BACKGROUND: The type and architecture of bone are very important factors in the successful implant treatment, and it is manifested that higher implant failure is more likely in the poorer quality of bone. Conventional bone classifications have recently been questioned because they are subjective and retrospective. PURPOSE: This clinical study aimed to determine the variations of the bone density in dental implant recipient sites using computerized tomography (CT). MATERIALS AND METHODS: The study group comprised of randomly selected 140 patients with 372 implant sites. Recipient sites for implant placement were determined based on CT data using implant planning StentCad software (Media Lab Software, La Spezia, Italy). The mean bone density values in Hounsfield unit (HU) of the simulated implant areas were recorded using the StentCad software. RESULTS: The HU values ranged from 68 to 1,603 HU. It was found that mean bone density values were 927 +/- 237, 721 +/- 291, 708 +/- 277, and 505 +/- 274 HU in the anterior mandible, posterior mandible, anterior maxilla, and posterior maxilla, respectively. CONCLUSION: Preoperative CT examination may be a useful method for determining the bone density of recipient areas before implant placement, and this valuable information about bone quality helps clinicians to make better treatment planning regarding the implant positions.