Diabetes mellitus and dental implants: a clinical study

Systemic Factors Affecting Prognosis of Dental Implants

Clinicians who place and restore implants are always concerned about the success and longevity of the same. There are several local and systemic factors that affect osseointegration and the health of the peri-implant tissues. In this study, we review the systemic factors that can affect implant survival, osseointegration, and long-term success. The study highlights the importance of delineating, and taking into consideration these systemic factors from the planning phase to the restorative phase of dental implants. A thorough medical history, including prescription and over-the-counter medications, is vital, as there may be numerous factors that could directly or indirectly influence the prognosis of dental implants.

Dental Implant Survival and Complication Rate over 2 Years for Individuals with Poorly Controlled Type 2 Diabetes Mellitus

BACKGROUND

Emerging evidence suggests that implant therapy may be a viable option for diabetic individuals with elevated glycemic levels.

PURPOSE

The purpose of this 2 year observational study was to evaluate survival and clinical complications of dental implants following placement in type 2 diabetes individuals having poor glycemic control.

MATERIALS AND METHODS

Adult participants (n = 24) with poorly controlled type 2 diabetes (8.0% ≤ HbA1c ≤ 12.0%) received two or more transgingival dental implants. Survival was evaluated after 1 (23 participants, 72 implants) and 2 (20 participants, 59 implants) years. Clinical complications were evaluated in 18 participants (52 implants) after 21-34 months. Relationships between complications and stratified HbA1c levels were assessed using Pearson's correlation test.

RESULTS

Survival rates were 98.6% (71/72 implants) after 1 year and 96.6% (57/59 implants) after 2 years. Complications were identified in 29% of participants with peri-implant mucositis, the most common event. Complications correlated directly with number of implants across HbA1c strata (0.42, R2  = 0.66). There was no correlation between HbA1c and the occurrences of complications or mucositis.

CONCLUSIONS

This 2-year evaluation supports the broader application of implant therapy in type 2 diabetes individuals with poor glycemic control in demonstrating high survival rates with limited complications.

Can the use of antibiotics interfere with the success of dental osseointegrated implants in diabetic patients?

AIM

The present review aims to discuss the last 10 years published data on the topic of the use of osseointegrated implants in diabetic subjects, particularly regarding the influence of antibiotics administration in the perioperative period.

BACKGROUND

In the last decades, oral rehabilitation significantly has evolved particularly with the use of osseointegrated implants. Increased life expectation of population is reflecting in a greater number of diabetic patients who might require dental osseointegrated implants rehabilitation. Diabetes was considered for a long time as a contraindication for oral implant placement. In this context, the use of antibiotics is still a controversial factor when we correlate it to implant success rate.

REVIEW RESULTS

Although 228 articles were initially selected for evaluation of proposed criteria, only 16 articles were considered valid. Among the 16 selected articles, only six articles represented clinical research that discussed the influence of the antibiotic in the success of osseointegration of dental implants in diabetic subjects. Five were retrospective studies and one a prospective research.

CONCLUSION

Data favors the use of antibiotics without significant side effects but clinical investigations of the need of prophylaxis antibiotic or therapeutic antibiotics are still scarce. The lack of adequate methodology is one of the main problems of the current articles. It is important to emphasize that studies should present detailed methodology in order to allow reproducibility.

CLINICAL SIGNIFICANCE

Permanent tooth loss is a pathological condition that affects millions of people worldwide. The possibility of successful treatment of edentulous areas through osseointegrated implants in those systemic compromised patients is a matter of scientific discussion. Although antimicrobial agents must be used rationally and carefully to avoid development of bacterial resistance, more studies are needed in order to support evidence regarding the influence of antibiotics in the success of dental implant surgery in diabetic patients.

Assessment of Maxillary and Mandibular Bone Density in Controlled Type II Diabetes: A Computed Tomography Study

This study was undertaken to compare the bone density in nondiabetic and controlled type II diabetes patients using spiral computed tomography. A group of 40 edentulous men, comprising of 20 nondiabetics and 20 controlled type II diabetics between the ages of 50-65 years, were enrolled in the study. Glycemic control of the diabetic patients was assessed by glycosylated hemoglobin level. The controlled diabetic group had an HbA1c level between 6.1-8%. A radiographic stent was prepared by using chemically cured resin. Bone densities at trabecular, buccal, and lingual cortical regions of maxillary and mandibular edentulous arches were measured by a tomography machine. Mean bone density measurements were recorded in Hounsfield units. The data thus obtained from 10 sites of maxillary and mandibular arches were tabulated and analyzed using SPSS statistical software. This study showed no significant changes in bone density between the controlled diabetic and nondiabetic subjects. Within the limitation of this study, it can be concluded that bone density does not seem to be affected in controlled type II diabetics.

A critical review of diabetes, glycemic control, and dental implant therapy

OBJECTIVES

To systematically examine the evidence guiding the use of implant therapy relative to glycemic control for patients with diabetes and to consider the potential for both implant therapy to support diabetes management and hyperglycemia to compromise implant integration.

MATERIAL AND METHODS

A systematic approach was used to identify and review clinical investigations directly assessing implant survival or failure for patients with diabetes. A MEDLINE (PubMED) database search identified potential articles for inclusion using the search strategy: (dental implants OR oral implants) AND (diabetes OR diabetic). Inclusion in this review required longitudinal assessments including at least 10 patients, with included articles assessed relative to documentation of glycemic status for patients.

RESULTS

Although the initial search identified 129 publications, this was reduced to 16, for inclusion. Reported implant failure rates for diabetic patients ranged from 0% to 14.3%. The identification and reporting of glycemic control was insufficient or lacking in 13 of the 16 studies with 11 of these enrolling only patients deemed as having acceptable glycemic control, limiting interpretation of findings relative to glycemic control. Three of the 16 studies having interpretable information on glycemic control failed to demonstrate a significant relationship between glycemic control and implant failure, with failure rates ranging from 0% to 2.9%.

CONCLUSIONS

Clinical evidence is lacking for the association of glycemic control with implant failure while support is emerging for implant therapy in diabetes patients with appropriate accommodations for delays in implant integration based on glycemic control. The role for implants to improve oral function in diabetes management and the effects of hyperglycemia on implant integration remain to be determined.

Dental implants in patients with osteoporosis: a clinical reality?

Osteoporosis is a systemic disorder characterized by generalized decrease in bone mineral density. Dental implantology is a specialty with high predictability when both quantity and quality of the bone are respected. Therefore, the diagnosis and the implant treatment in patients with osteoporosis are important. In the current study, a literature review about osteoporosis and dental implant therapy was conducted. PubMed, Cochrane, ISI, Dentistry Oral Science, SciELO, and Bireme databases were consulted over the last 20 years. English- and Portuguese-language articles were included in this revision. Some authors stated that the osteoporotic bone is similar to the proposed model of bone type IV. Randomized clinical studies reported implant failure in patients with osteoporosis after menopause. Studies that contraindicate the use of implants in patients with osteoporosis infer that the impaired bone metabolism led to reduction of bone healing around the implants. Nevertheless, other authors believe that the presence of osteoporosis is not a definitive condition to contraindicate the therapy with dental implants. In these cases, the dentist should perform a proper treatment planning, modifying the implant geometry, and use larger implant diameter and with surface treatment. Thus, osteoporosis is not a contraindication for implant surgery because an accurate analysis of bone quality by means tomography is performed.

Implant Installation With Ridge Augmentation Using Autogenous Bone Harvested From an Adjacent Site

In general, autogenous bone is the most predictable material of choice for augmentation procedure. However, the autogenous bone graft procedure requires an additional surgical wound, and the amount of graft is limited because of the donor site. In this case, autogenous corticocancellous bone cores were harvested adjacent to the implant surgical site and the defect, which was distal to the implant surface, was treated with autogenous bone and deproteinized bovine bone. The implant-supported prosthesis was functioning well up to 6 months without any probing depth or gingival inflammation.

Smoking, diabetes mellitus, periodontitis, and supportive periodontal treatment as factors associated with dental implant survival: a long-term retrospective evaluation of patients followed for up to 10 years

OBJECTIVES

To evaluate the factors associated with long-term implant survival in a large cohort of patients in regular follow-up until data collection.

METHODS

The study population consisted of 475 patients who were referred to a private clinic limited to Periodontics and Implantology between November 1995 and July 2006. Data were collected from patient files with regards to smoking habits, periodontal condition, diabetes mellitus, implant survival, and time when implant failure occurred. Patients were divided into those who participated in a supportive periodontal program in the clinic and those who only attended the annual free-of-charge implant examination.

RESULTS

A total of 1626 implants were placed with a follow-up ranging from 1 to 114 months (average 30.82 +/- 28.26 months). Overall, 77 (4.7%) implants were lost in 58 (12.2%) patients after a mean period of 24.71 +/- 25.84 months. More than one-half of the patients (246; 51.7%) participated in a structured supportive periodontal program in the clinic, and 229 (48.3%) only attended to the annual free-of-charge implant examination. Smoking and attendance in a regular supportive periodontal program were statistically associated with implant survival. Patients with (treated) moderate-to-advanced chronic periodontal disease demonstrated higher implant failure rates but, this difference did not reach statistical significance. Diabetes mellitus was not related to implant survival in this patient cohort.

CONCLUSIONS

Smoking and attendance in a regular supportive periodontal program were found to be strongly related to implant survival. Special attention should be given to continuous periodontal supportive programs to implant patients.

Glycemic control and implant stabilization in type 2 diabetes mellitus

Diabetes mellitus is considered a relative contra-indication for implant therapy. However, the effect of glycemic level on implant integration in persons with diabetes remains poorly understood. The hypothesis of this research was that poor glycemic control is directly related to short-term-impairment implant stabilization. This prospective clinical study evaluated 10 non-diabetic individuals (12 implants) and 20 persons with type 2 diabetes (30 implants). Glycated hemoglobin (HbA1c) levels ranged from 4.7-12.6%. Implant stability was assessed by resonance frequency analysis over 4 months following placement. Minimum stability levels were observed 2-6 weeks following placement for all 42 implants. Persons with HbA1c > or = 8.1% had a greater maximum decrease in stability from baseline and required a longer time for healing, as indicated by return of stability level to baseline. This study demonstrates alterations in implant stability consistent with impaired implant integration for persons with type 2 diabetes mellitus in direct relation to hyperglycemic conditions.

Repair process of surgical defects filled with autogenous bone grafts in tibiae of diabetic rats

From a biological standpoint, the best material for reconstruction of bone defects is the autogenous bone graft. However, as tissue healing is affected under diabetic conditions, major changes might take place in the revascularization, incorporation, replacement and remodeling phases of the grafted area. The purpose of this study was to assess the bone healing process in surgical wounds prepared in tibiae of diabetic rats and filled with autogenous bone. Forty male rats (Rattus norvegicus albinus, Wistar) were randomly assigned to receive an endovenous injection (penile vein) of either citrate buffer solution (Group 1 - control; n=20) or streptozotocin dissolved in citrate buffer solution (35 mg/kg) to induce diabetes (Group 2 - diabetic; n=20). After determination of glycemia, the animals were anesthetized and the anterolateral regions of the tibiae of both limbs were shaved, antisepsis was performed and longitudinal incisions were made in each limb. The tibiae were exposed and two 2-mm-diameter surgical cavities were prepared: one in the right limb, filled with particulate autogenous bone and the other in the left limb, filled with blood clot. The animals were euthanized at 10 and 30 postoperative days. The anatomic pieces were obtained, submitted to laboratory processing and sections were stained by hematoxylin and eosin and Masson's Trichrome for histomorphologic and histometric analyses. In both groups, the wounds filled with autogenous bone graft showed better results than those filled with blood clot. The control group showed higher new bone formation in wounds filled with autogenous bone graft at 30 days than the diabetic group, but without statistical significance. It may be concluded that, in general, the new bone formation occurred with autogenous graft was quantitatively similar between control and diabetic groups and qualitatively better in the control group.

Implant success in people with type 2 diabetes mellitus with varying glycemic control: a pilot study

BACKGROUND

The authors conducted a prospective cohort study to explore the relationship between implant success and glycemic control in patients with type 2 diabetes mellitus.

METHODS

The authors used a two-phased enrollment, stratified by glycated hemoglobin (HbA1c) levels, to evaluate 50 implants in 35 subjects. The authors assessed nonsubmerged, nonrestored implants after placement, during healing and at abutment placement (35 newton centimeters) for restoration after four months. Outcomes assessed included implant success or failure, clinical complications and adverse events.

RESULTS

The HbA1c levels of the subjects ranged from 4.5 to 13.8 percent. All 50 implants were integrated clinically. The authors identified three minor complications in three patients having HbA1c levels ranging from 7.4 to 8.3 percent. None of these complications affected the clinical management of the cases, and the authors did not identify any adverse events.

CONCLUSIONS

There was no evidence of diminished clinical success or significant early healing complications associated with implant therapy based on the glycemic control levels of subjects with type 2 diabetes mellitus.

CLINICAL IMPLICATIONS

These findings support the continued investigation of the effects of glycemic control on implant therapy toward the development of therapeutic guidelines that will optimize implant therapy in patients with diabetes.

Prevalence and risk variables for peri-implant disease in Brazilian subjects

OBJECTIVES

The aim of this study was to verify the prevalence of peri-implant disease and analyse possible risk variables associated with peri-implant mucositis and peri-implantitis. The study group consisted of 212 partially edentulous subjects rehabilitated with osseointegrated implants.

MATERIAL AND METHODS

The implants placed were examined clinically and radiographically to assess the peri-implant status. The degree of association between peri-implant disease and various independent variables was investigated using a multinomial regression analysis.

RESULTS

The prevalence of peri-implant mucositis and peri-implantitis were 64.6% and 8.9%, respectively. In univariate modelling, healthy peri-implant subjects presented lower plaque scores, less periodontal bleeding on probing, and less time elapsed since placement of supra-structures. In multivariate analyses, the risk variables associated with increased odds for having peri-implant disease included: gender, plaque scores, and periodontal bleeding on probing. Presence of periodontitis and diabetes were statistically associated with increased risk of peri-implantitis. The only two factors, which did not contribute to the presence of the disease, were the time elapsed since placement of supra-structures and the frequency of visits for maintenance care.

CONCLUSION

Our data suggest that subjects with periodontitis, diabetes, and poor oral hygiene were more prone to develop peri-implantitis.

A comprehensive and critical review of dental implant placement in diabetic animals and patients

OBJECTIVES

A thorough and exhaustive analysis of the available studies concerning placement of endosseous dental implants in diabetic subjects has not been previously published. The aim of the present study was to perform a comprehensive and critical review of experimental and clinical studies published in the international peer-reviewed literature in the English language regarding endosseous implant installation in diabetic subjects and to draw evidence-based conclusions on the effectiveness and predictability of dental implant therapy in diabetic patients.

MATERIAL AND METHODS

Literature search for articles published up to and including March 2005 in the English language was performed with a personal computer (PC) using The National Library Of Medicine (http://www.ncbi.nlm.nih.gov/PubMed) and Cochrane Oral Health Group databases. Search strategy included a specific series of terms and key words. The reference lists of identified publications, relevant texts and previous workshops were also scanned. Data sources also included several hand-searched journals and contact with experts, when it was considered appropriate. Search was conducted independently by the three reviewers (S. K., I. K. K., I. F.). At the first phase of selection the titles and abstracts and at the second phase full papers were screened independently by the three reviewers. Disagreement regarding inclusion of full papers was resolved by discussion among the reviewers.

RESULTS

The search provided 227 potentially relevant titles and abstracts. At the first phase of evaluation, 199 publications were rejected based on title and abstract. At the second phase, the full text of the remaining 28 publications was retrieved for more detailed evaluation. These publications included 11 experimental studies and 16 clinical studies (one clinical study corresponded to two publications). Finally, 11 experimental and eight clinical studies were accepted. Clinical studies included four prospective and four retrospective studies. Because of the limited number of available studies and their heterogeneity, focusing on a specific predefined question to be answered by a systematic review was not feasible and therefore no meta-analysis was planned.

CONCLUSION

Within the limits of the existing investigations, experimental studies seem to reveal an impaired bone healing response to implant placement in diabetic animals compared with non-diabetic controls, both quantitatively and qualitatively. The majority of clinical studies tend to indicate that diabetes is no contraindication for implant placement, on condition that it remains under metabolic control. However, definitive guidelines with objective criteria, such as type and duration of diabetes and glucosylated hemoglobin levels, need to be established in the future.

Systemic diseases affecting osseointegration therapy

OBJECTIVES

To evaluate the impact of systemic diseases and their treatment on the success of osseointegration therapy.

MATERIAL AND METHODS

A search was made to find human studies including subjects treated with osseointegrated oral implants, with a diagnosis of 11 systemic diseases, and reporting at least implant survival.

RESULTS

For most conditions, no studies comparing patients with and without the condition in a controlled setting were found. The evidence to recommend implant therapy was low and consisted in presentations of some successfully treated cases. With regard to diabetes, three types of reports were found: eight case series of diabetic patients treated with implants, six cross-sectional, longitudinal or retrospective evaluations of groups of subjects treated with implants, including some diabetic patients, and one matched control retrospective chart survey. The heterogeneity of the material and the method of data reporting precluded a formal meta-analysis. No unequivocal tendency for subjects with diabetes to have higher failure rates emerged, but the largest of these studies indicated a significant increase in the relative risk of implant failure with diabetes. The data obtained from 17 papers reporting data from osteoporotic patients were also heterogeneous. The evidence for an association of osteoporosis and implant failure was low.

CONCLUSIONS

The level of evidence indicative of absolute and relative contraindications for implant therapy due to systemic diseases is low. Many conditions have been listed as potentially critical, but studies comparing patients with and without the condition in a controlled setting are sparse.

Single-Tooth Implant Restorations: A Retrospective Study

Single-tooth implant restorations are a demanding clinical endeavor. Predictable results can be achieved when clinicians adhere to a recommended protocol for placement and reconstruction. As the demand to use implants to replace single missing teeth increased, so did the demand for superior esthetic outcome and immediate insertion and loading. The present study presents a 6-year audit of single-tooth implant restorations at Riyadh Dental Centre with a survival probability of 93.8% after a 5-year period. The recent trend of immediate insertion and loading results was also encouraging but still needs technical refinement as well as long-term follow-up review between different protocols.

A review of selected dental literature on evidence-based treatment planning for dental implants: Report of the Committee on Research in Fixed Prosthodontics of the Academy of Fixed Prosthodontics

This literature review summarizes research with the aim of providing dentists with evidence-based guidelines to apply when planning treatment with osseointegrated implants. Peer-reviewed literature published in the English language between 1969 and 2003 was reviewed using Medline and hand searches. Topics reviewed include systemic host factors such as age, gender, various medical conditions, and patient habits, local host factors involving the quantity and quality of bone and soft tissue, presence of present or past infection and occlusion, prosthetic design factors, including the number and arrangement of implants, size and coatings of implants, cantilevers and connections to natural teeth, and methods to improve outcomes of implant treatment in each category. The review demonstrated that there is no systemic factor or habit that is an absolute contraindication to the placement of osseointegrated implants in the adult patient, although cessation of smoking can improve outcome significantly. The most important local patient factor for successful treatment is the quality and quantity of bone available at the implant site. Specific design criteria are provided, including guidelines for spacing of implants, size, materials, occlusion, and fit. Limitations in the current body of knowledge are identified, and directions for future research are suggested.

The Use of Acupuncture in Implant Dentistry

This article aims to review how acupuncture can provide complimentary treatments to patients through implant rehabilitation. The following topics are discussed: control of gagging reflex, control of postoperative vomiting, control of postoperative pain, enhance anesthetic effects, control of anxiety, increase saliva production, enhance immune responses, management of temporomandibular dysfunction, smoking cessation, control diabetic mellitus, stimulation of peripheral nerve regeneration, and adverse effects.