Type 2 diabetes affects postextraction socket healing and influences first‐stage implant surgery: A study based on clinical and animal evidence

Prevalence and Factors Influencing Post-Operative Complications following Tooth Extraction: A Narrative Review

Background

Complications from dental extractions may result in multiple post-operative visits and adversely affect the patient's life. Preventing complications may decrease post-operative morbidity for the individual as well as lower societal costs, such as lost time from work and healthcare costs.

Objectives

This narrative review aims to assess the prevalence and factors influencing post-operative complications following tooth extraction, helping clinicians minimise the risk. Data Sources. Cross-sectional studies. Study Eligibility and Participants. Patients undergoing dental extractions. Our exclusion criteria included in vitro studies, animal studies, terminally ill patients, and tooth loss not due to dental extraction. Literature was collected from "PubMed" and "Web of Science" through search criteria based on the "PICO" framework. Twenty articles were used to formulate a prevalence table, and 156 articles were included for the factors influencing complications. Study Appraisal and Synthesis Methods. This narrative review was reported using the SANRA (a scale for the quality assessment of narrative review articles) checklist. Due to the scope of our narrative review and its associated objectives, the quality of cross-sectional studies (AXIS) will be conducted from the studies outlining the prevalence.

Results

Alveolar osteitis appears to be the most prevalent post-operative complication following tooth extraction. Predisposing factors can be significant in their ability to alter the risk of postoperative complications, and clinicians should provide patient-centred care to mitigate this risk. Limitations. Due to the breadth of context, a systematic review was not feasible, as it may have introduced heterogeneity.

Conclusion

This narrative review has highlighted an array of factors which can influence the prevalence of post-operative complications. Future research would benefit from individually reporting post-operative complications, reducing the heterogeneity in definitions of the complications, and including greater detail on the predisposing factors studied.

Longitudinal analysis of microcirculatory parameters in gingival tissues after tooth extraction in patients with different risk profiles for wound healing disorders - a pilot study

OBJECTIVES

We aimed to establish a risk profile for intraoral wound healing disorders based on measurements of microcirculation in gingival tissues.

MATERIALS AND METHODS

Oxygen saturation (SO2) and blood flow in gingival tissues were measured with tissue spectrometry and laser doppler spectroscopy in 37 patients before/after tooth extractions. Patients were assigned to four groups: anamnestically and periodontally healthy patients (n = 7), anamnestically healthy but suffering from periodontitis (n = 10), anamnestically healthy but smoking and suffering from periodontitis (n = 10) and suffering from diabetes and periodontitis (n = 10). Measurements were performed at three different time points: Baseline measurement (T0), one day post extractionem (p.e.) (T1) and seven days p.e. (T2).

RESULTS

Baseline SO2 values were higher in control patients (p = .038). This effect was most evident in comparison to smokers suffering from periodontitis (p = .042), followed by diabetics suffering from periodontitis (p = .09). An opposite trend was seen for blood flow. Patients suffering from periodontitis demonstrated higher blood flow values (p = .012). Five patients, which belonged to the group of smokers suffering from periodontitis, showed clinically a delayed wound healing.

CONCLUSION

Differences in SO2 and blood flow of gingival tissue could be detected in different groups of patients with existing periodontitis compared to control patients.

CLINICAL RELEVANCE

Lower baseline SO2 values could be a warning signal for possible wound healing disorders after oral surgery.

Regeneration of alveolar bone defects in the experimental pig model: A systematic review and meta-analysis

OBJECTIVE

Pigs are emerging as a preferred experimental in vivo model for bone regeneration. The study objective was to answer the focused PEO question: in the pig model (P), what is the capacity of experimental alveolar bone defects (E) for spontaneous regeneration in terms of new bone formation (O)?

METHODS

Following PRISMA guidelines, electronic databases were searched for studies reporting experimental bone defects or extraction socket healing in the maxillae or mandibles of pigs. The main inclusion criteria were the presence of a control group of untreated defects/sockets and the assessment of regeneration via 3D tomography [radiographic defect fill (RDF)] or 2D histomorphometry [new bone formation (NBF)]. Random effects meta-analyses were performed for the outcomes RDF and NBF.

RESULTS

Overall, 45 studies were included reporting on alveolar bone defects or extraction sockets, most frequently in the mandibles of minipigs. Based on morphology, defects were broadly classified as 'box-defects' (BD) or 'cylinder-defects' (CD) with a wide range of healing times (10 days to 52 weeks). Meta-analyses revealed pooled estimates (with 95% confidence intervals) of 50% RDF (36.87%-63.15%) and 43.74% NBF (30.47%-57%) in BD, and 44% RDF (16.48%-71.61%) and 39.67% NBF (31.53%-47.81%) in CD, which were similar to estimates of socket-healing [48.74% RDF (40.35%-57.13%) and 38.73% NBF (28.57%-48.89%)]. Heterogeneity in the meta-analysis was high (I2 > 90%).

CONCLUSION

A substantial body of literature revealed a high capacity for spontaneous regeneration in experimental alveolar bone defects of (mini)pigs, which should be considered in future studies of bone regeneration in this animal model.

Artesunate-loaded thermosensitive chitosan hydrogel promotes osteogenesis of maxillary tooth extraction through regulating T lymphocytes in type 2 diabetic rats

BACKGROUND

Type 2 diabetes mellitus (T2DM) causes severe bone loss after tooth extraction as a hyperglycemic environment causes aberrant bone homeostasis. Artesunate (ART) is known to possess anti-inflammation and osteogenic properties. However, its osteogenesis property in alveolar bone remains unclear. This study aimed to explore the osteogenic and immunoregulatory effects of artesunate-loaded thermosensitive chitosan hydrogel (ART-loaded TCH) on maxilla tooth extraction in T2DM rats.

METHODS

T2DM rats were induced by a high-fat diet and streptozotocin. Different concentrations of ART-loaded TCH were applied in tooth extraction sockets. Bone loss and the expression of osteogenic regulatory factors (OPG, ALP, RANK) were evaluated. The immunoregulatory effects of ART-loaded TCH were observed through detecting the infiltration of T lymphocytes and their cytokines. The underlying mechanisms were explored.

RESULTS

Results showed that the 150 mg/ml ART-loaded TCH group significantly ameliorated maxilla bone height and bone mineral density when compared with the T2DM group (p < 0.05). It also improved the expression of OPG, ALP, and RANK. Although the alteration of CD4+ T, CD8+ T, and CD4+:CD8+ T ratio has no significant difference among groups, the release of Th1 and Th2 in the 150 mg/ml ART-loaded TCH group has been significantly regulated than in the T2DM group (p < 0.05). Besides, ART-loaded TCH treatment inhibited the expression of p38 MAPK and ERK1 in T2DM maxilla.

CONCLUSIONS

Therefore, the results indicated that 150 mg/ml ART-loaded TCH could be an effective method to prevent bone loss in T2DM tooth extraction rats by modulating the immunoregulation of Th1 and Th2 and the MAPK signaling pathway.

The response of salivary proinflammatory biomarkers to tooth extraction in individuals with type II diabetes mellitus

PURPOSE

This study investigated the levels of salivary proinflammatory cytokines in the saliva of patients living with type II diabetes mellitus (DM) compared to those in healthy individuals three times: before tooth extraction and at 2 hours and 2 days after tooth extraction.

METHODS

The study included 27 participants. Among them, 20 (n = 20; 74%) had type II DM, and seven (n = 7; 26%) were healthy control subjects. Saliva samples were collected at three time intervals: before tooth extraction and 2 hours and 2 days after tooth extraction. The salivary biomarkers were investigated using a Luminex multiplex assay. These salivary biomarkers included tumor necrosis factor-alpha (TNF-α), interleukin 6 (IL-6), interleukin 1-beta (IL-1β), and interferon-gamma (IFN-γ).

RESULTS

At baseline, patients with type II DM had significantly lower levels of IL-1β (P = 0.016). Moreover, 2 hours after extraction, patients with type II DM had significantly lower levels of IL-1β and TNF-α than did healthy control subjects (P = 0.046 and P = 0.020, respectively). In addition, 2 days after tooth extraction, the DM group had significantly greater IL-6 levels (P = 0.010) than the control group.

CONCLUSIONS

In patients with type II DM, salivary proinflammatory biomarker levels are generally comparable or lower than those in healthy control subjects. Proinflammatory cytokines manifest differently in patients with type II DM after tooth extraction than in normal healthy individuals. There is generally a delayed early response of salivary proinflammatory markers in patients living with type II DM who undergo tooth extraction.

The Effect of Coenzyme Q10/Collagen Hydrogel on Bone Regeneration in Extraction Socket Prior to Implant Placement in Type II Diabetic Patients: A Randomized Controlled Clinical Trial

Background: The healing of an extraction socket leads to alveolar ridge resorption that can hinder future implant placement and further rehabilitation with special concerns in diabetes mellitus. Coenzyme Q10 (CoQ10) has been developed as a new material for alveolar socket augmentation. The aim of this study was to investigate the effect of CoQ10 hydrogel on bone regeneration after extraction of mandibular teeth in Type II diabetic patients. Methods: This trial was registered under the number NCT05122299 and included eighteen patients. The hydrogel was first prepared and characterized. After tooth extraction, the hydrogel was placed in the extraction sockets. Bone formation was evaluated three months after tooth extraction. Results: The bone density was significantly higher in the CoQ10 group than the other two groups measured on cone beam computed tomography (CBCT). The relative gene expression of Runt-related transcription factor 2 (RUNX2) and Osteopontin (OPN) showed significant increase in the presence of CoQ10. Histomorphometry revealed significantly less fibrous tissue in the CoQ10 group in comparison to the control or collagen group. Conclusion: The local application of CoQ10 after tooth extraction provided a simple, inexpensive, yet effective treatment facilitating bone formation and healing in the extraction sockets of diabetic patients.

Pathogenesis and treatment of wound healing in patients with diabetes after tooth extraction

Diabetes mellitus is a common systematic chronic disease amongst dental patients. The elevated glucose microenvironment can prolong the healing of tooth extraction sockets. Therefore, the promotion of healing up tooth extraction sockets is of great clinical importance to the patients with diabetes mellitus. The current evidence indicates the mechanism of the recovery period of extraction sockets in hyperglycaemia conditions from physiological, inflammation, immune, endocrine and neural aspects. New advancements have been made in varied curative approaches and drugs in the management of wound healing of tooth extraction sockets in diabetes. However, most of the interventions are still in the stage of animal experiments, and whether it can be put into clinical application still needs further explorations. Specifically, our work showed topical administration of plasma-rich growth factor, advanced platelet-rich fibrin, leukocyte- and platelet-rich fibrin and hyaluronic acid as well as maxillary immediate complete denture is regarded as a promising approach for clinical management of diabetic patients requiring extractions. Overall, recent studies present a blueprint for new advances in novel and effective approaches for this worldwide health ailment and tooth extraction sockets healing.

Diabetic wound healing in soft and hard oral tissues

There is significant interest in understanding the cellular mechanisms responsible for expedited healing response in various oral tissues and how they are impacted by systemic diseases. Depending upon the types of oral tissue, wound healing may occur by predominantly re-eptihelialization, by re-epithelialization with substantial new connective tissue formation, or by a a combination of both plus new bone formation. As a result, the cells involved differ and are impacted by systemic diaseses in various ways. Diabetes mellitus is a prevalent metabolic disorder that impairs barrier function and healing responses throughout the human body. In the oral cavity, diabetes is a known risk factor for exacerbated periodontal disease and delayed wound healing, which includes both soft and hard tissue components. Here, we review the mechanisms of diabetic oral wound healing, particularly on impaired keratinocyte proliferation and migration, altered level of inflammation, and reduced formation of new connective tissue and bone. In particular, diabetes inhibits the expression of mitogenic growth factors whereas that of pro-inflammatory cytokines is elevated through epigenetic mechanisms. Moreover, hyperglycemia and oxidative stress induced by diabetes prevents the expansion of mesengenic cells that are involved in both soft and hard tissue oral wounds. A better understanding of how diabetes influences the healing processes is crucial for the prevention and treatment of diabetes-associated oral complications.

Strontium-incorporated titanium implant surfaces treated by hydrothermal treatment enhance rapid osseointegration in diabetes: A preclinical vivo experimental study

OBJECTIVES

The aim of the current study was to explore effects of strontium-incorporated titanium implant surfaces by hydrothermal treatment on osseointegration in diabetic rats.

MATERIALS AND METHODS

The surface characteristics of SLA and SLA-Sr surfaces were detected by related instruments. Thirty-six male Sprague-Dawley rats were induced into diabetes, and thirty-six rats were normal. SLA and SLA-Sr implants were, respectively, inserted into bilateral tibial metaphysis of each rat. Percentage of bone-to-implant contact (BIC%) and percentage of bone area (BA%) were analyzed at 4 and 8 weeks after implantation. Immunohistochemistry of osteoprotegerin (OPG) and Wnt5a were conducted at 1 and 4 weeks. Gene expression levels of inflammatory cytokines and related signaling molecules in peri-implant bone tissue were detected at 3 and 7 days.

RESULTS

Strontium was uniformly distributed on SLA-Sr surfaces, and it was released in an effective concentration range. SLA-Sr surfaces showed significantly higher BIC% in diabetic rats at 4 (p < .05) and 8 weeks (p < .05). Besides, it displayed higher BIC% at 4 weeks (p < .05) in normal rats. Also, SLA-Sr surfaces upregulated expression of OPG at 4 weeks (p < .05) in diabetic rats. What's more, SLA-Sr surfaces downregulated inflammation (TNF-α, IL-1β, and IL-6; p < .01) in diabetic rats at 3 days. In addition, expression of Wnt5a and ROR2 was upregulated (p < .05) at 7 days after implantation under diabetes.

CONCLUSION

It is suggested that strontium-incorporated titanium implant surfaces by hydrothermal treatment could enhance implant osseointegration as compared with SLA implant surfaces in diabetic rats.

Clinical and radiographic variables related to implants with simultaneous grafts among type 2 diabetic patients treated with different hypoglycemic medications: a retrospective study

Background

The influence of different hypoglycemic agents on peri-implant variables among type 2 diabetes mellitus patients is still unclear. Therefore, the aim of this study was to assess the radiographic marginal bone loss and clinical parameters around implants in patients using different hypoglycemic agents.

Methods

In this retrospective cohort study, the dental implant records of type 2 diabetes mellitus patients who met the inclusion criteria were collected. The patients using only single medication as follows: insulin, metformin, or glucagon-like peptide-1 (GLP-1) drugs, were grouped according to their medication. These patients received implant placement with the same initial status, and all the prosthesis restorations were cement-retained ceramic crowns. The peri-implant marginal bone levels were evaluated by periapical radiographs immediately after implant placement and at 1 and 2-year follow-up visits. The baseline characteristics were compared among groups. The peri-implant radiographic marginal bone loss and clinical parameters were preliminarily compared using the Kruskal–Wallis test, and then the covariates were controlled by covariance analysis. Bonferroni post hoc adjustment test was performed for the multiple comparisons.

Results

After a review of more than 7000 medical records, a total of 150 patients with 308 implants at 1-year follow-up were assessed. The peri-implant marginal bone loss in the GLP-1 drug group was significantly smaller than the insulin group and metformin group (P < 0.01). The radiographic bone loss in the metformin group was higher than the insulin group (P < 0.05). Some of these included patients were lost to follow-up. Only 74 patients with 129 implants completed the 2-year follow-up. The radiographic bone loss in the metformin group was still higher than the insulin group (P < 0.05) and GLP-1 group (P < 0.01). There was no significant difference in the BOP (+) and the mean PD among groups (P > 0.05).

Conclusions

The radiographic variables were not exactly the same among the patients with different hypoglycemic agents at both the 1 and 2-year follow-ups. After ensuring consistency in baseline characteristics, the positive effect of GLP-1 drugs on peri-implant bone remodeling may be no less than insulin or metformin. More studies are needed to verify the direct effect of these drugs on peri-implant bone.

Clinical trial registration number ChiCTR2000034211 (retrospectively registered).

Abnormal macrophage polarization impedes the healing of diabetes-associated tooth sockets

Patients with poorly controlled type 2 diabetes mellitus (T2DM) often experience delayed tooth extraction socket (TES) healing. Delayed healing is often associated with an aberrant inflammatory response orchestrated by either M1 pro-inflammatory or M2 anti-inflammatory macrophages. However, the precise mechanism for the attenuated TES healing remains unclear. Here we used diet-induced T2DM mice as a model to study TES. Compared with the control group, the T2DM group showed delayed TES healing and diminished expression of osteogenic and angiogenic genetic profiles. Meanwhile, we detected a more inflammatory profile, with more M1 macrophages and TNF-α expression and less M2 macrophages and PPARγ expression, in TES in the T2DM group when compared to control mice. In vitro co-culture models showed that M1 macrophages inhibited the osteogenic capacity of bone marrow stromal cells and the angiogenic capacity of endothelial cells while M2 macrophages showed an opposite effect. In addition, we constructed a gelatin/β-TCP scaffold with IL-4 to induce macrophage transformation towards M2 polarization. In vitro analyses of the hybrid scaffold revealed sustained release of IL-4 and a phenotype switch to M2 macrophages. Finally, we demonstrated that sustained IL-4 release significantly increased expression of osteogenic and angiogenic genetic profiles and improved TES healing in T2DM mice. Together, we report that increased M1 and decreased M2 macrophage polarization may be responsible for delayed TES healing in T2DM patients through abnormal expression of TNF-α and PPARγ. This imbalance negatively influences osteogenesis and angiogenesis, two of the most important biological factors in bone wound healing. Enhancing M2 macrophage polarization with IL-4 delivery system may represent a potential strategy for promoting the healing of TES in T2DM patients.

Inhibition of GDF11 could promote bone healing in the tooth extraction socket and facilitate mesenchymal stem cell osteogenic differentiation in T2DM pigs

BACKGROUND

Growth differentiation factor 11 (GDF11) might be a key factor responsible for the weakening of mesenchymal stem cell (MSC) osteogenic differentiation in tooth extraction sockets in patients with type 2 diabetes mellitus (T2DM). This study aimed to confirm that inhibition of GDF11 could promote bone healing in tooth extraction sockets and facilitate MSC osteogenic differentiation under T2DM conditions.

METHODS

Three streptozotocin-induced T2DM pig models and two control pig models were established. The T2DM pigs were treated with an intrasocket injection of GDF11 inhibitor in the left mandible, whereas the right side was maintained for natural healing. The postextraction socket healing of the T2DM pigs was compared with that of nondiabetic controls. Healing was quantitatively verified by microcomputed tomography, and the GDF11 expression level was detected. MSCs from T2DM pig sockets were cultured and treated with a GDF11 inhibitor. The osteogenic differentiation ability of MSCs was also compared among groups.

RESULTS

The expression of GDF11 in the tooth extraction sockets from T2DM pigs increased significantly post extraction. Bone healing was promoted by periodic injection of the GDF11 inhibitor into the extraction sockets of T2DM pigs. Furthermore, the osteogenic differentiation ability of T2DM-MSCs was improved in pigs treated with the GDF11 inhibitor.

CONCLUSIONS

GDF11 inhibition could promote bone healing in the tooth extraction socket and facilitate MSC osteogenic differentiation under T2DM conditions. GDF11 could be a potential therapeutic target for undesirable alveolar bone healing in T2DM patients.