1
|
Jain R, Ghosh M, Goel R, Gupta R, Golhait P, Ghosh B. A challenging journey of maxillofacial implants placement and rehabilitation in an irradiated exenterated socket. J Oral Biol Craniofac Res 2022; 12:319-323. [DOI: 10.1016/j.jobcr.2022.03.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 08/02/2021] [Accepted: 03/18/2022] [Indexed: 10/18/2022] Open
|
2
|
Xu HQ, Wang CG, Zhou Q, Gao YH. Effects of alcohol consumption on viral hepatitis B and C. World J Clin Cases 2021; 9:10052-10063. [PMID: 34904075 PMCID: PMC8638036 DOI: 10.12998/wjcc.v9.i33.10052] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Revised: 04/15/2021] [Accepted: 08/25/2021] [Indexed: 02/06/2023] Open
Abstract
The liver is the main target organ for hepatitis viruses and the vital organ for alcohol metabolism. These two factors of viral hepatitis and alcohol abuse in combination can exert dual harmful actions, leading to enhanced damage to the liver. Epidemiological studies have revealed a higher prevalence of hepatitis C virus (HCV) infection among alcoholics than the general population. The interaction of alcohol with viral hepatitis [e.g., hepatitis B virus (HBV), HCV] and the underlying mechanisms are not fully understood. The effects of alcohol on viral hepatitis include promoted viral replication, weakened immune response, and increased oxidative stress. Clinically, alcohol abuse is correlated with an increased risk of developing end-stage liver cirrhosis and hepatocellular carcinoma in patients with chronic hepatitis B and C, suggesting that the combination of alcohol and HBV/HCV lead to more severe liver damage. The influence of mild to moderate alcohol drinking on the HBV-induced liver fibrosis, cirrhosis, and hepatocellular carcinoma among patients infected with HBV remains unclear. Unlike HBV infected patients, no safe level of alcohol intake has been established for patients with HCV. Even light to moderate alcohol use can exert a synergistic effect with viral hepatitis, leading to the rapid progression of liver disease. Furthermore, interferon-based therapy is less effective in alcohol drinkers than in control patients, even after abstinence from alcohol for a period of time. Therefore, abstaining from alcohol is highly recommended to protect the liver, especially in individuals with HBV/HCV infection, to improve the clinical efficacy of antiviral treatment and prevent the rapid progression of chronic viral hepatitis.
Collapse
Affiliation(s)
- Hong-Qin Xu
- Department of Hepatology, The First Hospital of Jilin University, Jilin University, Changchun 130021, Jilin Province, China
| | - Chun-Guang Wang
- Department of Surgery, The Second Hospital of Jilin University, Jilin University, Changchun 130041, Jilin Province, China
| | - Qiang Zhou
- Department of Hepatology, The First Hospital of Jilin University, Jilin University, Changchun 130021, Jilin Province, China
| | - Yan-Hang Gao
- Department of Hepatology, The First Hospital of Jilin University, Jilin University, Changchun 130021, Jilin Province, China
| |
Collapse
|
3
|
Padala SR, Asikainen P, Ruotsalainen T, Mikkonen JJ, Silvast TS, Koistinen AP, Schulten EAJM, Ten Bruggenkate CM, Kullaa AM. Effects of irradiation in the mandibular bone loaded with dental implants. An experimental study with a canine model. Ultrastruct Pathol 2021; 45:276-285. [PMID: 34423726 DOI: 10.1080/01913123.2021.1962467] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Radiation therapy may compromise the quality of bone around dental implants, and its ability to regenerate, remodel, and revascularize. This study aimed to describe the irradiation effect on the bone microstructure of the mandible using dental implants in a canine model. Five beagle dogs were exposed to 40 Gy fractionated radiation. In total, 20 dental implants were inserted, two in the irradiated and two in the non-irradiated side. The mandible bone blocks were subjected to 3D micro-computed tomography (µCT) imaging, later evaluated histomorphometrically by light microscopy and scanning electron microscopy. Alterations in irradiated bone were observed under µCT imaging showing an increased anisotropy, porosity, and pore volume. Bone surface-to-bone volume decreased. The bone to implant contact index was significantly reduced in the irradiated bone (75.6% ± 5.8%) as compared to the non-irradiated bone (85.1% ± 6.8%). In the irradiated mandible, osteocytes with their filopodial processes, the bone beneath the periosteum, and subperiosteal veins showed structural differences but were not significant, whereas the diameter of Haversian canals were smaller statistical significant as compared to the control side. The study highlights that radiation dosage of fractioned 40 Gy causes alterations in the alveolar bone microstructure with compatible osseointegration and clinically stable dental implants.
Collapse
Affiliation(s)
- Sridhar Reddy Padala
- Clinical Research, Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland
| | | | - Timo Ruotsalainen
- Institute of Dentistry, Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland
| | - Jopi Jw Mikkonen
- Institute of Dentistry, Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland.,SIB Labs, Faculty of Science and Forestry, University of Eastern Finland, Kuopio, Finland
| | - Tuomo S Silvast
- SIB Labs, Faculty of Science and Forestry, University of Eastern Finland, Kuopio, Finland
| | - Arto P Koistinen
- SIB Labs, Faculty of Science and Forestry, University of Eastern Finland, Kuopio, Finland
| | - Engelbert A J M Schulten
- Department of Oral and Maxillofacial Surgery/ Oral Pathology, Amsterdam University Medical Centers, Academic Centre for Dentistry Amsterdam (ACTA), Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Chris M Ten Bruggenkate
- Department of Oral and Maxillofacial Surgery/ Oral Pathology, Amsterdam University Medical Centers, Academic Centre for Dentistry Amsterdam (ACTA), Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Arja M Kullaa
- Institute of Dentistry, Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland
| |
Collapse
|
4
|
Moore P, Grinsell D, Lyons B, Hewson I. Outcomes of dental and craniofacial osseointegrated implantation in head and neck cancer patients. Head Neck 2019; 41:3290-3298. [DOI: 10.1002/hed.25845] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Revised: 05/11/2019] [Accepted: 06/04/2019] [Indexed: 12/12/2022] Open
Affiliation(s)
- Phillip Moore
- ENT/Head and Neck UnitSt Vincent's Hospital Melbourne Victoria Australia
| | - Damien Grinsell
- Plastic, Reconstructive, and Hand Surgery UnitSt Vincent's Hospital Melbourne Victoria Australia
| | - Bernard Lyons
- ENT/Head and Neck UnitSt Vincent's Hospital Melbourne Victoria Australia
| | - Ian Hewson
- ENT/Head and Neck UnitSt Vincent's Hospital Melbourne Victoria Australia
| |
Collapse
|
5
|
Doh RM, Kim S, Keum KC, Kim JW, Shim JS, Jung HS, Park KM, Chung MK. Postoperative irradiation after implant placement: A pilot study for prosthetic reconstruction. J Adv Prosthodont 2016; 8:363-371. [PMID: 27826386 PMCID: PMC5099128 DOI: 10.4047/jap.2016.8.5.363] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Revised: 06/08/2016] [Accepted: 08/08/2016] [Indexed: 11/23/2022] Open
Abstract
PURPOSE On maxillofacial tumor patients, oral implant placement prior to postoperative radiotherapy can shorten the period of prosthetic reconstruction. There is still lack of research on effects of post-implant radiotherapy such as healing process or loading time, which is important for prosthodontic treatment planning. Therefore, this study evaluated the effects of post-implant local irradiation on the osseointegration of implants during different healing stages. MATERIALS AND METHODS Custom-made implants were placed bilaterally on maxillary posterior edentulous area 4 weeks after extraction of the maxillary first molars in Forty-eight Sprague-Dawley rats. Experimental group (exp.) received radiation after implant surgery and the other group (control) didn't. Each group was divided into three sub-groups according to the healing time (2, 4, and 8 week) from implant placement. The exp. group 1, 2 received 15-Gy radiation 1 day after implant placement (immediate irradiation). The exp. group 3 received 15-Gy radiation 4 weeks after implant placement (delayed irradiation). RESULTS The bone mineral density (BMD) was significantly lower in the immediate irradiation groups. BMD was similar in the delayed irradiation group and the control group. The irradiated groups exhibited a lower bone-to-implant contact ratio, although the difference was not statistically significant. The irradiated groups also exhibited a significantly lower bone volume and higher empty lacuna count than the control groups. No implant failure due to local irradiation was found in this study. CONCLUSION Within the limits of this study, the timing of local irradiation critically influences the bone healing mechanism, which is related to loading time of prostheses.
Collapse
Affiliation(s)
- Re-Mee Doh
- Department of Advanced General Dentistry, Dankook University College of Dentistry, Cheonan, Republic of Korea
| | - Sungtae Kim
- Department of Periodontology, Dental Research Institute, Seoul National University School of Dentistry, Seoul, Republic of Korea
| | - Ki Chang Keum
- Department of Radiation Oncology, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Jun Won Kim
- Department of Radiation Oncology, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - June-Sung Shim
- Department of Prosthodontics, Yonsei University College of Dentistry, Seoul, Republic of Korea
| | - Han-Sung Jung
- Division in Anatomy and Development Biology, Department of Oral Biology, Yonsei University College of Dentistry, Seoul, Republic of Korea
| | - Kyeong-Mee Park
- Department of Advanced General Dentistry, Yonsei University College of Dentistry, Seoul, Republic of Korea
| | - Moon-Kyu Chung
- Division in Anatomy and Development Biology, Department of Oral Biology, Yonsei University College of Dentistry, Seoul, Republic of Korea
| |
Collapse
|
6
|
Soares PBF, Nunes SA, Franco SD, Pires RR, Zanetta-Barbosa D, Soares CJ. Measurement of Elastic Modulus and Vickers Hardness of Surround Bone Implant Using Dynamic Microindentation - Parameters Definition. Braz Dent J 2014; 25:385-90. [DOI: 10.1590/0103-6440201300169] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2014] [Accepted: 10/20/2014] [Indexed: 01/15/2023] Open
Abstract
The clinical performance of dental implants is strongly defined by biomechanical principles. The aim of this study was to quantify the Vicker's hardness (VHN) and elastic modulus (E) surround bone to dental implant in different regions, and to discuss the parameters of dynamic microindantion test. Ten cylindrical implants with morse taper interface (Titamax CM, Neodent; 3.5 mm diameter and 7 mm a height) were inserted in rabbit tibia. The mechanical properties were analyzed using microhardness dynamic indenter with 200 mN load and 15 s penetration time. Seven continuous indentations were made distancing 0.08 mm between each other perpendicularly to the implant-bone interface towards the external surface, at the limit of low (Lp) and high implant profile (Hp). Data were analyzed by Student's t-test (a=0.05) to compare the E and VHN values obtained on both regions. Mean and standard deviation of E (GPa) were: Lp. 16.6 ± 1.7, Hp. 17.0 ± 2.5 and VHN (N/mm2): Lp. 12.6 ± 40.8, Hp. 120.1 ± 43.7. No statistical difference was found between bone mechanical properties of high and low profile of the surround bone to implant, demonstrating that the bone characterization homogeneously is pertinent. Dynamic microindantion method proved to be highly useful in the characterization of the individual peri-implant bone tissue.
Collapse
|
7
|
Poort L, Lethaus B, Böckmann R, Buurman D, Jong JD, Hoebers F, Kessler P. Experimental Studies on the Irradiation of Facial Bones in Animals: A Review. ACTA ACUST UNITED AC 2014. [DOI: 10.4236/ijohns.2014.33022] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
8
|
Chambrone L, Mandia J, Shibli JA, Romito GA, Abrahao M. Dental implants installed in irradiated jaws: a systematic review. J Dent Res 2013; 92:119S-30S. [PMID: 24158336 DOI: 10.1177/0022034513504947] [Citation(s) in RCA: 71] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The aim of this study was to assess the survival rate of titanium implants placed in irradiated jaws. MEDLINE, EMBASE, and CENTRAL were searched for studies assessing implants that had been placed in nongrafted sites of irradiated patients. Random effects meta-analyses assessed implant loss in irradiated versus nonirradiated patients and in irradiated patients treated with hyperbaric oxygen (HBO) therapy. Of 1,051 potentially eligible publications, 15 were included. A total of 10,150 implants were assessed in the included studies, and of these, 1,689 (14.3%) had been placed in irradiated jaws. The mean survival rate in the studies ranged from 46.3% to 98.0%. The pooled estimates indicated a significant increase in the risk of implant failure in irradiated patients (risk ratio: 2.74; 95% confidence interval: 1.86, 4.05; p < .00001) and in maxillary sites (risk ratio: 5.96; 95% confidence interval: 2.71, 13.12; p < .00001). Conversely, HBO therapy did not reduce the risk of implant failure (risk ratio: 1.28; 95% confidence interval: 0.19, 8.82; p = .80). Radiotherapy was linked to higher implant failure in the maxilla, and HBO therapy did not improve implant survival. Most included publications reported data on machined implants, and only 3 studies on HBO therapy were included. Overall, implant therapy appears to be a viable treatment option for reestablishing adequate occlusion and masticatory conditions in irradiated patients.
Collapse
Affiliation(s)
- L Chambrone
- Division of Periodontics, Department of Stomatology, School of Dentistry, University of São Paulo, São Paulo, SP, Brazil
| | | | | | | | | |
Collapse
|
9
|
von Wilmowsky C, Moest T, Nkenke E, Stelzle F, Schlegel KA. Implants in bone: part II. Research on implant osseointegration: material testing, mechanical testing, imaging and histoanalytical methods. Oral Maxillofac Surg 2013; 18:355-72. [PMID: 23430020 DOI: 10.1007/s10006-013-0397-2] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2013] [Accepted: 02/04/2013] [Indexed: 11/28/2022]
Abstract
PURPOSE In order to determine whether a newly developed implant material conforms to the requirements of biocompatibility, it must undergo rigorous testing. To correctly interpret the results of studies on implant material osseointegration, it is necessary to have a sound understanding of all the testing methods. The aim of this overview is to elucidate the methods that are used for the experimental evaluation of the osseointegration of implant materials. DISCUSSION In recent decades, there has been a constant proliferation of new materials and surface modifications in the field of dental implants. This continuous development of innovative biomaterials requires a precise and detailed evaluation in terms of biocompatibility and implant healing before clinical use. The current gold standard is in vivo animal testing on well validated animal models. However, long-term outcome studies on patients have to follow to finally validate and show patient benefit. CONCLUSION No experimental set-up can provide answers for all possible research questions. However, a certain transferability of the results to humans might be possible if the experimental set-up is carefully chosen for the aspects and questions being investigated. To enhance the implant survival rate in the rising number of patients with chronic diseases which compromise wound healing and osseointegration, dental implant research on compromised animal models will further gain importance in future.
Collapse
Affiliation(s)
- Cornelius von Wilmowsky
- Mund-,Kiefer- und Gesichtschirurgische Klinik Universitätsklinikum Erlangen, Glückstrasse 11, 91054, Erlangen, Germany,
| | | | | | | | | |
Collapse
|
10
|
Thoma DS, Martin IS, Mühlemann S, Jung RE. Systematic review of pre-clinical models assessing implant integration in locally compromised sites and/or systemically compromised animals. J Clin Periodontol 2012; 39 Suppl 12:37-62. [PMID: 22533946 DOI: 10.1111/j.1600-051x.2011.01833.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
OBJECTIVE The aim was to systematically search the dental literature for pre-clinical models assessing implant integration in locally compromised sites (part 1) and systemically compromised animals (part 2), and to evaluate the quality of reporting of included publications. METHODS A Medline search (1966-2011) was performed, complimented by additional hand searching. The quality of reporting of the included publications was evaluated using the 20 items of the ARRIVE (Animals in Research In Vivo Experiments) guidelines. RESULTS One-hundred and seventy-six (part 1; mean ARRIVE score = 15.6 ± 2.4) and 104 (part 2; 16.2 ± 1.9) studies met the inclusion criteria. The overall mean score for all included studies amounted to 15.8 ± 2.2. Housing (38.3%), allocation of animals (37.9%), numbers analysed (50%) and adverse events (51.4%) of the ARRIVE guidelines were the least reported. Statistically significant differences in mean ARRIVE scores were found depending on the publication date (p < 0.05), with the highest score of 16.7 ± 1.6 for studies published within the last 2 years. CONCLUSIONS A large number of studies met the inclusion criteria. The ARRIVE scores revealed heterogeneity and missing information for selected items in more than 50% of the publications. The quality of reporting shifted towards better-reported pre-clinical trials within recent years.
Collapse
Affiliation(s)
- Daniel S Thoma
- Clinic of Fixed and Removable Prosthodontics and Dental Material Science, University of Zurich, Zurich, Switzerland.
| | | | | | | |
Collapse
|
11
|
Jegoux F, Malard O, Goyenvalle E, Aguado E, Daculsi G. Radiation effects on bone healing and reconstruction: interpretation of the literature. ACTA ACUST UNITED AC 2010; 109:173-84. [PMID: 20123406 DOI: 10.1016/j.tripleo.2009.10.001] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2009] [Revised: 09/03/2009] [Accepted: 10/04/2009] [Indexed: 10/20/2022]
Abstract
OBJECTIVE Reconstructing irradiated mandibles with biomaterials is still a challenge but little investigated. We collected data that could help us understand studies in the field of regeneration with biomaterials and irradiated bone. STUDY DESIGN Systematic review of the literature. RESULTS Delay and duration of radiation delivery and total equivalent dose are the most variable parameters in the various studies, resulting in confusion when interpreting the literature. Most reproducible experiments show that radiation reduces osteogenic cell numbers, alters cytokine capacity, and delays and damages bone remodeling. Interindividual variations and how such changes become irreversible lesions are still uncertain. In the case of regeneration using biomaterials, most studies have addressed the question of reconstruction in previously irradiated bone. The results show that osseointegration is often possible, although the failure rate is higher. The sooner the implantation takes place after the end of the radiation, the higher the likelihood of failure. Few studies have focused on primary reconstruction followed by early irradiation, and most of the currently available engineering models would be altered by radiation. Good outcomes have been obtained with bone morphogenetic protein and with total bone marrow transplanation. CONCLUSION This review points out the difficulties in achieving reproducible experiments and interpreting literature in this underinvestigated field.
Collapse
|
12
|
Jégoux F, Goyenvalle E, Cognet R, Malard O, Moreau F, Daculsi G, Aguado E. Reconstruction of irradiated bone segmental defects with a biomaterial associating MBCP+(R), microstructured collagen membrane and total bone marrow grafting: an experimental study in rabbits. J Biomed Mater Res A 2010; 91:1160-9. [PMID: 19148925 DOI: 10.1002/jbm.a.32274] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
The bone tissue engineering models used today are still a long way from any oncologic application as immediate postimplantation irradiation would decrease their osteoinductive potential. The aim of this study was to reconstruct a segmental critical size defect in a weight-bearing bone irradiated after implantation. Six white New Zealand rabbits were immediately implanted with a biomaterial associating resorbable collagen membrane EZ(R) filled and micro-macroporous biphasic calcium phosphate granules (MBCP+(R)). After a daily schedule of radiation delivery, and within 4 weeks, a total autologous bone marrow (BM) graft was injected percutaneously into the center of the implant. All the animals were sacrificed at 16 weeks. Successful osseous colonization was found to have bridged the entire length of the defects. Identical distribution of bone ingrowth and residual ceramics at the different levels of the implant suggests that the BM graft plays an osteoinductive role in the center of the defect. Periosteum-like formation was observed at the periphery, with the collagen membrane most likely playing a role. This model succeeded in bridging a large segmental defect in weight-bearing bone with immediate postimplantation fractionated radiation delivery. This has significant implications for the bone tissue engineering approach to patients with cancer-related bone defects.
Collapse
|
13
|
Histomorphometric Analysis of HA-Coated Implants Interface With Irradiated and Nonirradiated Bone. IMPLANT DENT 2008; 17:414-21. [DOI: 10.1097/id.0b013e31818d3ebd] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
14
|
Ihde S, Kopp S, Gundlach K, Konstantinović VS. Effects of radiation therapy on craniofacial and dental implants: a review of the literature. ACTA ACUST UNITED AC 2008; 107:56-65. [PMID: 18755611 DOI: 10.1016/j.tripleo.2008.06.014] [Citation(s) in RCA: 94] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2008] [Revised: 06/06/2008] [Accepted: 06/13/2008] [Indexed: 12/20/2022]
Abstract
OBJECTIVES The theories of the effects of radiation therapy on craniofacial and dental implants have been challenged by new models. Animal and clinical studies differ on the importance of dose effect and implant location regarding implant survival. Our purpose was to explore the risks of irradiation regarding dose levels, timing of radiation, implant location, and material. STUDY DESIGN A systematic search of the literature was performed to identify studies reporting animal and human data on the success of implants in irradiated versus nonirradiated bone. RESULTS Eleven animal studies exploring histomorphometric, biomechanical, and histologic features of implants in irradiated bone were summarized. Sixteen human clinical studies evaluating craniofacial (n = 8) and dental (n = 8) implants in irradiated bone were summarized. No meta-analyses of dental implants in irradiated bone were found. Efficacy studies comparing different implant types in irradiated bone were not found. CONCLUSION Studies from both animal subjects and human patients indicate that irradiated bone has a greater risk of implant failure than nonirradiated bone. This increase in risk may be up to 12 times greater; however, studies making these comparisons are of poor to moderate quality, so the magnitude of this difference should be accepted with caution.
Collapse
Affiliation(s)
- Stefan Ihde
- Gommiswald Dental Clinic, Gommiswald, Switzerland.
| | | | | | | |
Collapse
|
15
|
Verdonck HWD, Meijer GJ, Laurin T, Nieman FH, Stoll C, Riediger D, Stoelinga PJW, de Baat C. Implant stability during osseointegration in irradiated and non-irradiated minipig alveolar bone: an experimental study. Clin Oral Implants Res 2007; 19:201-6. [PMID: 18067600 DOI: 10.1111/j.1600-0501.2007.01457.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
OBJECTIVES Primary implant stability is related to local bone density. After insertion of an implant, implant stability is subject to changes due to bone remodeling. In patients who have undergone radiotherapy in the head and neck region, implant stability is impaired because irradiation reduces bone vitality. The current study was designed to monitor and test implant stability immediately after implant placement and during osseointegration in irradiated and non-irradiated minipig alveolar bone. MATERIALS AND METHODS All maxillary and mandibular premolars and molars of six adult Göttingen minipigs were extracted. The maxilla and mandible of three minipigs received three irradiation exposures at a total dose of 24 Gy. After irradiation, five initial implant holes were drilled in the residual alveolar ridge of each edentulous site. In order to assess bone vascularity, laser Doppler flowmetry recordings were carried out in the initial holes. A total of 120 implants were placed in the six minipigs. Subsequently, and at 8, 16, and 24 weeks after implant placement, implant stability was recorded by resonance frequency analysis (RFA). RFA values were expressed as an implant stability quotient (ISQ). RESULTS ISQ values recorded immediately after implant placement showed no differences between irradiated and non-irradiated minipigs. Repeated measurements at the four recording moments showed a decrease of ISQ values in all minipigs, being more pronounced in irradiated bone, when compared with non-irradiated bone. The results at the third and fourth recording moments showed a stabilization or even a slight increase of ISQ values. CONCLUSIONS The results document the negative effect of irradiation on bone vascularity and hence on implant stability.
Collapse
Affiliation(s)
- Henk W D Verdonck
- Department of Oral and Maxillofacial Surgery, University Hospital Maastricht, Maastricht, The Netherlands.
| | | | | | | | | | | | | | | |
Collapse
|
16
|
Brasseur M, Brogniez V, Grégoire V, Reychler H, Lengelé B, D'Hoore W, Nyssen-Behets C. Effects of irradiation on bone remodelling around mandibular implants: an experimental study in dogs. Int J Oral Maxillofac Surg 2006; 35:850-5. [PMID: 16697145 DOI: 10.1016/j.ijom.2006.03.016] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2005] [Revised: 01/27/2006] [Accepted: 03/09/2006] [Indexed: 11/29/2022]
Abstract
This research focuses on the effects of radiotherapy on bone remodelling around mandibular implants in dogs. After bilateral extraction of the mandibular premolars and first 2 molars, each of 11 beagles received 8 mandibular implants. Four animals were irradiated 4 weeks after implantation and 4 others 8 weeks before implantation; the remaining 3 did not receive radiotherapy. Irradiation consisted of 10 daily fractions of 4.3Gy (60)Co. Fluorochromes were given at implantation and irradiation to allow the measurement of bone apposition. The dogs were killed 6 months after implantation. Each hemi-mandible was processed according to bone-specific histological techniques. New bone formation was visible around 85 of the 88 implants. Stimulated mandibular remodelling was attested in both irradiated groups by increased porosity and numerous labelled osteons. Resorption was more pronounced in the group irradiated after implantation, but osteon formation appeared unvarying. Osseointegration was thus shown to be compatible with bone irradiation as bone turnover activities were maintained throughout the experiment. As the apposition stage of the remodelling cycle appears crucial to achieve optimal osseointegration, its normal completion should be taken into account in clinical practice by respecting a 6-month period between irradiation and implantation.
Collapse
Affiliation(s)
- M Brasseur
- Prosthodontics Department, Dental School, Université catholique de Louvain, Belgium
| | | | | | | | | | | | | |
Collapse
|
17
|
Abstract
In order to ensure implant success, it is essential to select patients who do not possess local or systemic contraindications to therapy. Hence, it is the purpose of this paper to review the medical diseases that reportedly preclude conventional dental implant treatment. Absolute contraindications to implant rehabilitation include recent myocardial infarction and cerebrovascular accident, valvular prosthesis surgery, immunosuppression, bleeding issues, active treatment of malignancy, drug abuse, psychiatric illness, as well as intravenous bisphosphonate use. Any of these conditions bar elective oral surgery, and require judicious monitoring by the physician as well as the dental provider. Noncompliance to the suggested protocol may, in the worst possible case, result in patient mortality.
Collapse
Affiliation(s)
- Debby Hwang
- Department of Periodontics and Oral Medicine, School of Dentistry, University of Michigan, Ann Arbor, MI 48109-1078, USA
| | | |
Collapse
|
18
|
Oelgiesser D, Levin L, Barak S, Schwartz-Arad D. Rehabilitation of an irradiated mandible after mandibular resection using implant/tooth-supported fixed prosthesis: a clinical report. J Prosthet Dent 2004; 91:310-4. [PMID: 15116030 DOI: 10.1016/j.prosdent.2003.12.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Patients undergoing mandibular resection often have facial asymmetry and cosmetic disfigurement, which include a retruded, deviated mandible, motor and sensory deficiencies, and abnormal intermaxillary relationship and occlusion. An implant-supported fixed prosthesis can be an optimal treatment modality. However, there is a problem in creating a repeatable, stable plane of occlusion and maxillomandibular relationship. This report describes the treatment sequence and considerations to rehabilitate a patient undergoing mandibular resection and radiotherapy with an implant-supported fixed prosthesis.
Collapse
Affiliation(s)
- Dan Oelgiesser
- The Maurice and Gabriela Goldschleger School of Dental Medicine, Tel Aviv University, Tel Aviv, Israel.
| | | | | | | |
Collapse
|
19
|
Knabe C, Hoffmeister B. Implant-supported titanium prostheses following augmentation procedures: A clinical report. Aust Dent J 2003; 48:55-60. [PMID: 14640159 DOI: 10.1111/j.1834-7819.2003.tb00010.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND This report describes a novel technique for fabricating retrievable implant-supported titanium (Ti) prostheses in patients requiring a comprehensive treatment plan involving the combined efforts of maxillofacial surgery and implant prosthodontics. METHODS Following bone graft reconstructive surgery and implant placement prosthetic treatment was initiated by inserting ITI-Octa abutments. An impression was made, and a framework was fabricated by fusing Ti-cast frameworks to prefabricated titanium copings by laser-welding. This was followed by veneering or fabrication of a removable denture with Ti metal re-enforcement. RESULTS Favourable clinical results have been achieved using these screw-retained Ti implant-supported restorations for patients treated with reconstructive bone graft-surgery, with clinical observation periods ranging from three to four years. CONCLUSIONS The present observations suggest that these screw-retained implant-supported Ti prostheses may be a meaningful contribution to implant prosthodontics, facilitating retrievable restorations of optimum biocompatibility, good marginal precision and with a good esthetic result. However, controlled clinical studies are needed to establish the long-term serviceability of these Ti restorations.
Collapse
Affiliation(s)
- C Knabe
- Department of Experimental Dentistry, University Hospital Benjamin Franklin, Free University of Berlin, Germany.
| | | |
Collapse
|