Need for lateral bone augmentation at two narrow-diameter implants: A prospective, controlled, clinical study.

OBJECTIVES: To detect the potential influence of implant diameter and anatomic factors on the need for bone augmentation procedures (BAPs) when replacing congenitally missing lateral incisors (MLIs). MATERIALS AND METHODS: Patients with congenitally missing MLIs with a mesio-distal distance between the canine and the central incisor of 5.9-6.3 mm received a Ø2.9 mm implant while Ø3.3 mm implants were placed when the distance was 6.4-7.1 mm. The following linear measurements were recorded using a calliper: width of the alveolar process (WAP), width of the bony alveolar ridge (WAR) and thickness of the facial bone after implant osteotomy (TFB). Guided bone regeneration was performed in case of fenestration- or dehiscence-type defects or a thin TFB (<1.7 mm). RESULTS: Fifty Ø2.9 mm and 50 Ø3.3 mm were included in 100 patients. WAP and WAR did not differ between the groups (p > .05). TFB was statistically significant larger in the Ø2.9 group (1.75 ± 0.59 mm) compared to the Ø3.3 group (1.5 ± 0.63 mm) (p = .041). Fenestration-type defects (p = .005) and a thin facial bone wall (p = .045) was observed more frequently in the Ø3.3 compared to the Ø2.9 group. Correspondingly, BAP was indicated more frequently in the Ø3.3 compared to the Ø2.9 group (p = .017). WAP, MD and WAR were statistically significant correlated to the need for BAP (p < .001). As independent variable, only WAR influenced the probability of BAP (p < .001). CONCLUSION: The use of 2.9 diameter implants was correlated to a reduced frequency of BAP compared to 3.3 mm implants, without reaching a statistically significant difference. Measurement of the WAP provides the clinician useful information to predict BAP.

Effect of Low-Level Laser Irradiation on Stability and Marginal Bone of Narrow Implants Retaining Overdentures in Moderately Controlled Diabetic Patients.

The researchers investigated the influence of low-level laser irradiation (LLLI) on implant stability and marginal bone of small-diameter implants retaining mandibular overdentures in patients with moderately controlled diabetes. Twenty patients (mean age = 59.32 ± 4.1 years) with moderately controlled diabetes mellitus (glycated hemoglobin A1c [HbA1c] = 8.1%-10.0 %) were rehabilitated by maxillary and mandibular conventional dentures. Two small-diameter implants (3 × 12 mm) were inserted in the canine areas of the mandible and immediately loaded by mandibular dentures. In a split-mouth design, LLLI was applied to 1 of the 2 implants in a random order (study group [SG]); the other implant was left as a control (control group [CG]). For each patient, gallium aluminum-arsenide diode low-level laser (940-nm wavelength, 0.50 ± 2 mW output power, 0.004 cm2 spot size; Epic, Biolase, Inc, San Clemente, Calif) was applied around each implant with total delivered energy of 90 J (equally divided by 6 irradiation points) in 3 sessions. The application was done immediately after implant insertion, 3 days and 1 week after surgery. Implant stability (measured by Periotest) and marginal bone loss (MBL; measured by cone beam computerized tomography) were evaluated at implant loading (T1), 6 months (T6), and 12 months (T12). One implant failed in the CG and no failures occurred in the SG, resulting in 95% and 100% survival rates, respectively. The SG recorded higher Periotest values than the CG at all observation times. However, the difference was significant (P = .039) at T6 only. The SG recorded lower MBL values than the CG. No difference in MBL was detected between groups or peri-implant sites (mesial, distal, buccal, and lingual) at T6 and T12. Within the limits of this study, LLLI had no effect on marginal bone around immediately loaded small-diameter implants retaining overdentures in patients with moderately controlled diabetes. However, it was beneficial in improving implant stability 6 months after overdenture insertion.

Immediate small-diameter implants as abutments for an overdenture in the edentulous atrophic mandible: report of immersion endoscopic bone in vivo, and histologic bone-implant evaluation after 6 months of function / Implantes de pequeño diámetro como soporte inmediato de sobredentaduras en hueso alveolar mandibular atrófico: reporte de endoscopía de inmersion in vivo y evaluación histológica a los 6 meses de función

The aim of this report was to endoscopically evaluate bone quality in vivo in the immediate installation of temporary small-diameter implants, and again after 6 months of function, through an attachments system for overdenture, in the atrophic mandible of a patient. We also histologically evaluated bone-implant interaction in these temporary small-diameter implants, once the success of the osseointegration of the submerged implants was guaranteed. A patient received a total of 6 implants in the atrophic mandible, two of which were immediately loaded with a provisional prosthesis, and four were left to heal in a submerged way. Further, an immersion endoscopic evaluation was performed during bone drilling, and this showed a compact bone structure with limited vascularization and predominantly cortical structure.This immediate loading protocol involving an overdenture retained by two small-diameter implants of 2.9 mm in the atrophic mandible proved to be successful after 6 months of loading. Clinical and histologic osseointegration was consistently achieved for both of the retrieved immediately loaded implants. This modality allows the patient to be restored with a stable, functional, and aesthetic prosthesis during the osseointegration period of submerged implants and soft-tissue healing, before the removal of the provisional implants. The histological evaluation of bone-implant contact found that the space between the implant threads closer to the surface was filled with woven bone and lamellar bone, but the tissue in contact with the cervical portion of the implants was compatible with cortical bone organization. Also, the newly formed bone has a regular cell distribution and characteristics of advanced maturation after 6 months of function in the atrophic mandible. Anchored overdentures in 2 to 4 small-diameter implants (2.9 mm) for edentulous patients with severe atrophy of the mandible with cortical bone would be a minimally invasive alternative.

Retrospective study on the clinical outcomes of small-diameter implants supporting fixed prostheses without bone augmentation in the posterior region after 2 to 12 years.

BACKGROUND: Small-diameter implants (SDIs: diameter <3.5 mm) are often chosen as an alternative to bone augmentation in clinical practice, but the scientific evidence regarding SDI application in the posterior area remains deficient. PURPOSE: To evaluate the clinical and radiographic outcomes of SDIs supporting fixed prostheses without bone augmentation in the posterior region, and to analyze the potential influencing factors related to SDI failures. MATERIALS AND METHODS: Clinical and radiographic data of 243 SDIs in 156 patients were retrospectively assembled after 2 to 12 (mean 4.75) years of follow-up. Implant and prosthesis failures, mechanical and biological complications, and radiographic marginal bone loss (MBL) were evaluated. The influence of patient/implant characteristics and prosthetic design on SDI failures was investigated. RESULTS: Five implants in five patients failed, contributing to 10-year cumulative survival rates of 97.9% on an implant-based analysis and 96.8% on a patient-based analysis. Biological complications and mechanical complications were detected in 22 (9.1%) and 31 (12.8%) of implants, respectively. No implant fracture was detected. Peri-implant MBL during 10 years was 0.60 ± 0.90 mm on average. The implant type (bone-level or tissue-level) was the only factor that significantly influenced SDI failures. CONCLUSION: SDIs supporting fixed prostheses in the posterior region achieved predictable long-term clinical outcomes. However, tissue-level titanium SDIs should be avoided where possible.

Comparison of patient satisfaction with mini-implant versus standard diameter implant overdentures: a systematic review and meta-analysis of randomized controlled trials.

Mini-implants have certain advantages over standard size implants which are being tested in various randomized controlled trials. This systematic review and meta-analysis aims to compare conventional implant overdentures to mini-implant-retained overdentures as regards to patient satisfaction. Electronic databases were searched for eligible studies data required were extracted. The extracted data were analyzed using non-Cochrane mode in RevMan 5.0 software. The heterogeneity between the studies was assessed using Forest plot, I 2 statistics, and chi-square test with a statistical P value of less than 0.10 to indicate statistical significance. Random-effect models were used in case of moderate heterogeneity. Four studies were included for the review and two for meta-analysis. Two studies in 177 patients comparing quality of life with mini or standard diameter implants showed a pooled result of -4.76 [-6.48, -3.04] favoring the use of mini-implants. The results for other outcomes were incomputable due to inadequate studies. GRADE approach was used for quality of life, and the strength of evidence was observed to be "low". Mini-implant-supported overdentures had better patient satisfaction levels compared to standard diameter implant overdenture. There is definite lack of evidence to support the use of mini-implants for overdentures.

Histological and histomorphometric analyses of narrow implants, crestal and subcrestally placed in severe alveolar atrophy: a study in foxhound dogs.

BACKGROUND: Narrow-diameter implants provide an alternative to the horizontal augmentation techniques situations severe bone atrophy. Lack of bone width and interdental space has been regarded as an encumbrance in the case selection for prosthetic rehabilitation using dental implants. OBJECTIVE: The aim of the study was to evaluate bone-to-implant contact and marginal bone loss of two different narrow implants in resorbed ridges at different crestal positions. MATERIAL AND METHODS: 48 Bredent Narrow(®) implants (24 MiniSky(®) and NarowSky(®) ) were placed at crestal and subcrestal levels in healing bone of atrophic alveolar ridge of 6 American foxhounds. Histological and histomorphometric analyses of osseointegration were carried out at 4 and 8 weeks. RESULTS: Modeling in the marginal defect region was accompanied by marked decreases in the dimensions of both the buccal and the more lingual bone walls. Relative to BIC, significant differences were found in favor of subcrestal group, for both Narrow Sky and MiniSky. Linear measurements showed to be slightly high in the crestal group. With significant differences for PM-IS (peri-implant mucosa to implant shoulder) and IS-BC (implant shoulder to buccal bone crest). CONCLUSIONS: Within the limitations of animal study, it can be stated that the NarrowSky(test group) crestal and subcrestal implants showed less crestal bone resorption, higher ISQ values and most BIC at 4 and 8 weeks of evaluation compared with MiniSky implants (control group). The design of the implants plays an important role in peri-implant mucosa and crestal bone maintenance at 8-week follow-up period.

Uso de implantes de diâmetro reduzido nos casos de agenesia dentária na região estética / The use of small diameter dental implants for tooth agenesis in the esthetic region – a case report

Os implantes de diâmetro reduzido são definidos como os que possuem diâmetro menor do que 3,75 mm. Esse tipo de implante tem indicação restrita para os casos de rebordo alveolar atrófico, espaço protético mesiodistal menor do que 7 mm e substituição de dentes com pequenos diâmetros cervicais, com o intuito de oferecer um tratamento menos invasivo e que garanta a satisfação ao paciente. Assim, o objetivo do presente trabalho foi relatar um caso clínico com ênfase na exposição e na discussão da viabilidade da reabilitação de área estética com restrição nos espaços interdentais utilizando implantes de diâmetro reduzido. Um paciente do sexo masculino compareceu à clínica com queixa de ausências dos elementos 12 e 22 em virtude de agenesias dentárias. Após planejamento reverso, definiu-se a reabilitação implantossuportada com instalação de implantes de diâmetro reduzido nas regiões edêntulas. Um ano após a reabilitação, não foram evidenciadas sintomatologias dolorosas, infecciosas, instabilidade dos implantes e processos de reabsorção óssea. Com base neste caso clínico, foi possível sugerir que os implantes de diâmetro reduzido são uma opção segura e previsível para a reabilitação de regiões com limitações nos espaços interdentais e cristas alveolares delgadas

Small diameter implants are defined as those with a diameter less than 3.75 mm. This type of implant is indicated for atrophic alveolar ridges, a mesio-distal space < 7 mm and to substitute tooth with small cervical diameters, providing a less invasive treatment and better patient satisfaction. The aim of this article was to report a clinical case discussing rehabilitation of esthetic regions with small diameter implants. A male patient presented at the clinics with the lack of teeth 12 and 22 due to dental agenesis. After the reverse planning, an implant-supported restoration was defi ned at those regions. One year later, no evidence of painful symptoms, infection, implant instability, and bone resorption was seen. Considering this clinical case, it is possible to suggest that small diameter dental implants are a safe and predictable option for restricted interdental spaces and thin alveolar bone crests.

Clinical evaluation of small diameter straumann implants in partially edentulous patients: a 5-year retrospective study.

OBJECTIVE: The aim of the present study was to retrospectively evaluate small-diameter (3.3 mm) Straumann® dental implants placed in the maxilla or the mandible over a period of 5 years in function. MATERIALS AND METHODS: Twenty-eight partially edentulous patients received a total of 48 implants over a 5-year period. After the standard healing period (3 to 6 months), the implants were restored with single-tooth prostheses or fixed partial dentures. All patients were followed according to a strict maintenance program with regular recalls. The cumulative survival rates of implants were analyzed and prosthetic complications were assessed. RESULTS: After 5 years of function, one single 10-mm-long implant in the maxillary premolar region was lost because of recurrent peri-implant infection in a female patient. Two single 10-mm-long maxillary implants placed in the posterior region were lost due to body fracture. The cumulative 5-year survival rate of the implants was 93.75 %. The most common prosthetic complication was loosening of the occlusal screw. CONCLUSION: Within the limited observation period and the number of patients included in this study, it may be concluded that the use of small-diameter implants appears to be predictable if clinical guidelines are followed and appropriate prosthetic restorations are provided. However, it should be noted that fatigue fracture may occur.

Clinical outcome of narrow diameter implants inserted into allografts

OBJECTIVE: Narrow diameter implants (NDI) (i.e. diameter <3.75 mm) are a potential solution for specific clinical situations, such as reduced interradicular bone, thin alveolar crest and replacement of teeth with small cervical diameter. NDI have been available in clinical practice since the 1990s, but only few studies have analyzed their clinical outcome and no study have investigated NDI inserted in fresh-frozen bone (FFB) grafts. Thus, a retrospective study on a series of NDI placed in homologue FFB was designed to evaluate their clinical outcome. MATERIAL AND METHODS: In the period between December 2003 and December 2006, 36 patients (22 females and 14 males, mean age 53 years) with FFB grafts were selected and 94 different NDI were inserted. The mean follow-up was 25 months. To evaluate the effect of several host-, surgery-, and implant-related factors, marginal bone loss (MBL) was considered an indicator of success rate (SCR). The Kaplan Meier algorithm and Cox regression were used. RESULTS: Only 5 out of 94 implants were lost (i.e. survival rate - SVR 95.7 percent) and no differences were detected among the studied variables. On the contrary, the Cox regression showed that the graft site (i.e. maxilla) reduced MBL. CONCLUSIONS: NDI inserted in FFB have a high SVR and SCR similar to those reported in previous studies on regular and NDI inserted in non-grafted jaws. Homologue FFB is a valuable material in the insertion of NDI.