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Conventional implant dentistry has been limited to healed edentulous ridges with adequate bone. Predictable success rates resulted in using dental implants in compromised situations such as insertion into old infected sites or near to pathological areas. There is significant data about marginal bone loss and lack of osseointegration around the neck of implants. However, the data about peri apical implant bone loss is really rare.An electronic search was carried in PubMed regarding articles in the time period from 1980 to 2011. Subsequent manual search was performed included all animal and human case series and clinical trials. Reported success rates and treatment options were calculated in a systematic manner.There is conflicted data showing a relatively accepted success of implantation immediately after removal of infection directly or indirectly in contact with the apical portion of the implants. However, some complications may happen that must be managed.The available data about the periapical implant pathologies is relatively inadequate. However, concluded data represents some clinical comments in order to reduce the complexities.
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OBJECTIVE: Both anorganic bovine bone (ABB) and ß-tricalcium phosphate (ß-TCP) are used in clinical practice as bone substitute materials, but there is limited data comparing these two materials in standardized defects. The aim of this study was to histologically evaluate the effectiveness of ABB and ß-TCP in the healing of experimentally induced bone defects. MATERIALS AND METHODS: Eighteen bone defects were created on the calvaria of six rabbits. In each animal, one defect was left untreated and the other two were filled with ABB and ß-TCP. After one month, histological sections were prepared. Type and vitality of newly formed bone, percentage of new bone formation and residual material, thickness of trabeculae, inflammation and foreign body reaction were assessed. RESULTS: The newly formed osseous tissue was vital in all defects and consisted of woven and lamellar bone. Mean percentages of new bone formation were 30.83±14.29%, 16.83±11.07% and 14.00±8.17% in ß-TCP, ABB and control groups, respectively and the mean percentages of residual biomaterial were 24.17±14.01% and 36.50±8.43% in ß-TCP and ABB groups, respectively. However, the differences were not statistically significant (all ps>0.05). Inflammatory infiltration was statistically higher in ß-TCP compared to the control group (p=0.025), but the difference was not significant between ß-TCP and ABB groups (p=0.083). Trabeculation thickness and foreign body reaction were not statistically different between ß-TCP and ABB groups. CONCLUSION: ß-TCP and ABB were not different with regard to the quantity and quality of newly formed osseous tissue. However, inflammatory infiltration was higher in sites filled with ß-TCP.
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OBJECTIVE: Low-intensity laser therapy (LILT) is defined to supply direct biostimulative light energy to the cells. While several studies have demonstrated that LILT has stimulating effects on bone cells and can accelerate the repair process of the bone, others reported delayed fracture healing or no effects after LILT. The aim of this article was to review the studies evaluating the biomodulation effects of LILT on bone-derived stem cells. MATERIALS AND METHODS: To access relevant articles, searching in three electronic databases including PubMed, Google Scholar and Science Direct was conducted until April 2012. The key words used were low-level laser, low-intensity laser, low-power laser therapy, stem cell, bone marrow stem cell, bone and osteoblast. The articles that met the eligibility criteria were included in this review of literature. RESULTS: Twenty-five relevant articles (13 in vitro and 12 animal studies) were included. Eleven in vitro studies showed positive results with regard to acceleration of cell proliferation and differentiation. All animal studies showed improved bone healing in sites irradiated with low-intensity laser. CONCLUSION: Based on the results of the reviewed articles, low intensity laser therapy can accelerate bone healing in extraction sites, bone fracture defects and distraction osteogenesis, provided proper parameters were applied.
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OBJECTIVE: To determine the pattern of stability changes as a reflection of early healing around single-stage roughened-surface implants in humans utilizing resonance frequency analysis (RFA). MATERIALS AND METHODS: Hundred twenty-five patients who demanded dental implants were treated with two different implant (Nobel Biocare Replace™ and Strumman™ ITI) systems. Bone type was classified into four groups. RFA was used for direct measurement of implant stability on the day of implant placement and consecutively at 14, 30 and 60 days after placement. The data were analyzed with Student t test and regression analysis. RESULTS: Three-hundred four roughened surface implants placed in the maxilla and mandible were evaluated. In Replace™ implants the lowest mean stability measurement was at 30 days for all bone types and the stability did not change significantly in any of the bone types (p>0.05). ITI™ implants demonstrated the lowest stability at 60 days for type 1 and 30 days and baseline for type 2, 3 and 4 bones. In addition, there was significant differences in implant stability between bone types 1 and 4 (P<0.001), 2 and 3 (p<0.05), and bone types 3 and 4 (P=0.07) at all aforementioned times in ITI™ implants. In Replace™ implants, regarding the implant diameter, contrary to ITI implants, no significant stability changes were detected (p>0.05). No significant difference was observed regarding gender, age and lengths in both systems. CONCLUSION: In comparison to ITI™ implants, Replace™ implants revealed no significant difference in the pattern of stability changes among different bone types.
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OBJECTIVE: Low quality of the bone and insufficient bone due to the size of the sinus and resorption of the alveolar ridge decrease the long-term survival of implants in the posterior maxilla compared to other regions of the jaws. Surgical procedures to increase bone volume make it possible to place implants longer than 8 mm. In this situation sinus elevation makes it possible to place implants. We intend to evaluate peri-implant bone loss and survival of implants placed in elevated sinuses after 2 years and to compare with implants placed in the native posterior maxilla. MATERIALS AND METHODS: Twenty-five implants placed in sinuses that had been reconstructed with Bio-Oss and healed after 9 months were compared with 30 implants placed in the posterior maxilla without any surgery. The groups were compared using probing pocket depth, bleeding on probing, Plaque Index and bone loss immediately after implant placement surgery and 2 years postoperatively. The criterion for implant survival was presence or absence of the implant in the oral cavity, which was recorded in relevant forms in both groups. RESULTS: Three implants were lost; one in control and two in grafted sinuses. No significant differences were observed in the survival rates. In general, the mean bone loss around intrasinus and extrasinus implants was not significantly different. In the same context, no differences were observed between bleeding on probing, Plaque Index and probing pocket depths of two groups (P=0.397, P=0.637 and P=0.224, respectively). CONCLUSION: The survival and bone loss around intrasinus and extrasinus implants are similar.
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OBJECTIVE: Vertical bone loss evaluations in the Nobel Biocare Replace(®) Select Tapered (™) implant system in the human after one-year loading time. MATERIALS AND METHODS: This retrospective cross-sectional study was performed on 31 patients (14 men, 17 women; mean age, 60.39 years) receiving 170 implants (mean, 5.48 for each patient) of Groovy and Non-groovy designs in the Nobel Biocare Replace(®) Select Tapered (™) system. The marginal bone loss was measured at mesial and distal aspects of the implants on OPG x-rays after one-year follow-up. The data regarding the patient's gender, age, history of disease, smoking, bone type at implant location, loading time of prosthesis and implant, implant design, diameter and length were recorded by the patients' records and interview. The data were subjected to multiple linear regression and Pearson coefficient ratio regarding different factors. RESULTS: The mean (standard deviation) distal, mesial and overall bone loss was 0.688 mm (0.851), 0.665 mm (0.849) and 0.935 mm (0.905), respectively in the studied implants. No significant differences were found regarding implant location, bone quality at the implant region, implant design and bone graft reception. In addition, no significant correlation was found between the occurred bone loss and implant diameter, length and number of used splints. CONCLUSION: Due to the criteria mentioned for implant success in term of bone loss values after one-year loading time, Noble Biocare Replace(®) Select Tapered (™) implant system is an acceptable treatment option for implant restorations in this regard.
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To identify the prevalence and risk indicators of periodontal disease in high-school students in Tehran, Islamic Republic of Iran, the periodontal condition of 867 students aged 15-19 years was assessed using the community periodontal index of treatment needs [CPITN]. The results showed that 88.7% of these students had less than perfect periodontal health. Multiple regression analysis revealed that sex, parents' educational level, frequency of toothbrushing and flossing, preventive dental visits and presence of extracted teeth were significant risk indicators for periodontal disease. School-based oral health promotion and prevention programmes are needed
