Time management in multistep periodontal and implant treatments: a practical guide.

In addition to the proper selection of techniques, appropriate treatment sequencing and prioritization are prerequisites for successful periodontal and implant procedures. The aim of this study was to provide evidence-based time frames for various procedures pertaining to periodontal and implant treatment. A literature review was conducted to collect data on tissue healing; in areas in which data were lacking, the viewpoints of experienced clinicians were solicited to establish a consensus. This review reports recommended time frames for the healing processes associated with surgical crown-lengthening procedures (both functional and esthetic), fresh socket management, alveolar ridge management, soft tissue management, sinus floor augmentation, implant loading, and peri-implant defect management.

Clinical efficacy of intraoral ultrasonography versus transgingival probing for measurement of gingival thickness in different gingival biotypes: a clinical trial.

BACKGROUND: Transgingival probing is conventionally used for gingival thickness (GT) measurement. However, invasiveness is a major drawback of transgingival probing. Thus, researchers have been in search of alternative methods for measurement of GT. This study compared the clinical efficacy of intraoral ultrasonography and transgingival probing for measurement of GT in different biotypes. MATERIALS AND METHODS: This clinical trial was conducted on 34 patients requiring crown lengthening surgery. GT was measured at 40 points with 2- and 4-mm distances from the free gingival margin (FGM) of anterior and premolar teeth of both jaws in each patient by an intraoral ultrasound probe. For measurement of GT by the transgingival probing method, infiltration anesthesia was induced, and a #25 finger spreader (25 mm) was vertically inserted into the soft tissue until contacting bone. The inserted length was measured by a digital caliper with 0.01 mm accuracy. All measurements were made by an operator with high reliability under the supervision of a radiologist. Data were analyzed by t-test, Power and Effect Size formula, and intraclass correlation coefficient (ICC). RESULTS: The two methods were significantly different in measurement of GT in both thick and thin biotypes at 2- and 4-mm distances (P < 0.001). The two methods had a significant difference in both the mandible (P < 0.001) and maxilla (P < 0.001) and in both the anterior (P < 0.003) and premolar (P < 0.003) regions. Although the difference was statistically significant in t-tests, the power and effect formula proved it to be clinically insignificant. Also, the ICC of the two methods revealed excellent agreement. CONCLUSION: The results showed optimal agreement of ultrasound and transgingival probing for measurement of GT. TRIAL REGISTRATION: The study was approved by the ethics committee of Shahid Beheshti University of Medical Sciences on 2021-12-28 (IR.SBMU.DRC.REC.1400.138) and registered in the Iranian Registry of Clinical Trials on 2022-03-14 (IRCT20211229053566N1).

Comparison of the Volume and Histological Properties of Newly Formed Bone after the Application of Three Types of Bone Substitutes in Critical-Sized Bone Defects.

This study aimed to compare the volume and quality of the newly formed bone following application of two types of xenografts and one synthetic material in bone defects in rabbit calvaria from histological and micro-CT aspects. Four 8-mm defects were created in 12 rabbit calvaria. Three defects were filled with bone substitutes and one was left unfilled as the control group. The newly formed bone was evaluated histologically and also by micro-CT at 8 and 12 weeks after the intervention. The percentage of osteogenesis was comparable in histomor-phometric assessment and micro-CT. Histological analysis showed that the percentage of the newly formed bone was 10.92 ± 5.17%, 14.70 ± 11.02%, 11.47 ± 7.04%, and 9.45 ± 5.18% in groups bovine 1, bovine 2, synthetic, and negative control, respectively after 8 weeks. These values were 33.70 ± 11.48%, 26.30 ± 18.05%, 22.92 ± 6.30%, and 14.82 ± 8.59%, respectively at 12 weeks. The difference in the percentage of the new bone formation at 8 and 12 weeks was not significant in any group (P > 0.05) except for bovine 1 group (P < 0.05). Micro-CT confirmed new bone formation in all groups but according to the micro-CT results, the difference between the control and other groups was significant in this respect (P < 0.05). All bone substitutes enhanced new bone formation compared with the control group. Micro-CT assessment yielded more accurate and different results compared with histological assessment.

Periodontal phenotype modification in orthodontic patients.

OBJECTIVE: The purpose of this study was to assess the feasibility of phenotype modification in orthodontic patients using combined bone and soft tissue grafting substitutes. CLINICAL CONSIDERATION: The surgical procedure was conducted on 18 patients (3 males, 15 females). Periodontal phenotype modification was conducted using demineralized freeze-dried bone allograft and a xenogeneic collagen matrix. The following parameters were recorded for each tooth at baseline and 12-month follow-up: O'Leary plaque index (PI), probing depth (PD), bleeding on probing (BOP), gingival thickness (GT), keratinized tissue width (KTW), gingival recession (GR), and vestibular depth (VD). The results showed a statistically significant increase in GT (2.02 ± 0.39 mm), KTW (1.11 ± 0.82 mm), and VD (0.18 ± 1.16 mm) (p < 0.05). GR was also significantly decreased (1.02 ± 0.99 mm) (p < 0.05). CONCLUSION: Within the limitation of this study, the proposed approach enhanced the periodontal condition in orthodontic patients. However, further studies with a larger sample size are needed to ensure long-term stability. CLINICAL SIGNIFICANCE: Hard and soft tissue conditions have paramount importance for long-term periodontal stability. Phenotype modification in orthodontic patients can diminish the probability of adverse consequences and result in optimal esthetic outcomes. The proposed technique using combined bone and soft tissue substitutes indicated promising results and could be recommended in orthodontic patients with thin periodontal phenotypes.

Evaluation of matrix metalloproteinase-1, -2, -3, -7, and -13 gene polymorphisms in patients with chronic periodontitis and healthy controls.

OBJECTIVES: The current study aimed to investigate the association of matrix metalloproteinase- (MMP-) 1, -2, -3, -7, and -13 gene polymorphisms with chronic periodontitis (CP) in an Iranian population. MATERIALS AND METHODS: In this case-control study, 87 subjects with CP and 89 periodontally healthy subjects were allocated to case and control groups, respectively. Subjects' venous blood samples (5 cc) were collected, and DNA extraction was performed. A spectrophotometer was utilized to assess the concentration of extracted DNAs. The desired gene polymorphisms were examined using restriction fragment length polymorphism polymerase chain reaction (RFLP-PCR) followed by electrophoresis. Statistical analyses were done using the Pearson Chi-Square test, odds ratio, and t-Test using SPSS Version 28. RESULTS: The MMP-1 (-1607 1G/2G) rs1799750, MMP-3 (-1171 5A/6A) rs3025058, and MMP-7 (-181 A/G) rs11568818 gene polymorphisms significantly differed between case and control groups (PV = 0.019, 0.007, and 0.028, respectively). In contrast, the gene polymorphisms of MMP-2 (-1306 C/T) rs243865 and MMP-13 (-77 A/G) rs2252070 did not make a significant difference. Regarding allele frequencies, the presence of the 2G allele in the MMP-1 (-1607) rs1799750 genotype increased the CP susceptibility significantly, while subjects with the 6A allele in their MMP-3 (-1171) rs3025058 genotype showed significantly lower susceptibility to CP (PV = 0.008 and < 0.001, respectively). CONCLUSION: In the studied population, gene polymorphisms in the DNA sequences of MMP-1 (-1607 1G/2G) rs1799750, MMP-3 (-1171 5A/6A) rs3025058, and MMP-7 (-181 A/G) rs11568818 may have impacts on CP incidence. CLINICAL RELEVANCE: Clinicians should be cautious about the association between MMP-1, MMP-3, and MMP-7 gene polymorphisms and the incidence of chronic periodontitis during periodontal treatment planning.

Peri-Implant Tissue Health and Disease in the Pre- and Post-Loading Phases.

Considering the widespread use of dental implants, a precise definition for peri-implant tissue health and an appropriate classification for peri-implant diseases are imperative for researchers and dental clinicians. However, absence of a unanimous definition and an efficient classification system has created controversies in the published reports regarding the epidemiology and prevalence of peri-implant diseases. Moreover, lack of a standard system for differentiation of different grades of peri-implantitis further complicates the interpretation of reports regarding the diagnosis prevalence, treatment, and outcome of such conditions, and highlights the need for a classification system based on the severity of disease. Almost all of the currently available classification systems focus on the assessment of health or disease status of the tissues around loaded implants. The purpose of the present study is to propose a classification/scoring system for peri-implant tissue health before and after prosthetic loading. This grading system can aid the researchers and dental clinicians in assessment of peri-implant tissue condition both before and after prosthetic loading of dental implants.

Short-term and long-term success and survival rates of implants supporting single-unit and multiunit fixed prostheses: A systematic review and meta-analysis.

STATEMENT OF PROBLEM: Whether placing implants to replace each missing tooth or using implant-supported fixed partial dentures provides better outcomes is unclear. PURPOSE: The purpose of this systematic review and meta-analysis was to assess the success and survival rates of implants supporting single-unit and multiunit fixed prostheses by using conventional protocols for placement and loading in short- and long-term follow-ups. MATERIAL AND METHODS: An electronic search was conducted in PubMed, Scopus, and Web of Science for studies published up to March 17, 2022. Comparative studies that reported the success or survival rates of both single-unit and splinted multiunit prostheses were considered for qualitative and quantitative analyses. RESULTS: A total of 68 publications comprising 11 271 implants were included. Compared with the single prostheses, the splinted multiunit group showed no significant differences in implant success rates in the short-term (risk difference=-0.004; 95% confidence interval (CI)=-0.033 to 0.025; P=.780) and long-term (risk difference=0.003; 95% confidence interval (CI)=-0.029 to 0.034; P=.874) follow-ups. Significant statistical differences were also not found in terms of the survival rates of the 2 groups (short-term risk difference=-0.004; 95% CI=-0.031 to 0.023; P=.779, long-term risk difference=-0.002; 95% CI=-0.029 to 0.025; P=.887). CONCLUSIONS: Implants supporting single-unit or splinted multiunit prostheses seem to be a predictable treatment in terms of survival and success over short and long periods. Nonetheless, it seems that cantilever and nonsplinted multiunit prostheses should be used with more caution.

Immediate implant placement in compromised sockets: A systematic review and meta-analysis.

STATEMENT OF PROBLEM: Immediate implant placement provides a popular therapeutic option. However, compromised sockets may jeopardize the treatment outcome. PURPOSE: The purpose of this systematic review and meta-analysis was to investigate the treatment outcome in terms of the implant survival rate and success parameters of immediate implant placement in compromised extraction sockets. MATERIAL AND METHODS: An electronic search was conducted in PubMed, Embase, Cochrane Library, and ISI Web of Science up to January 2021. Studies evaluating implant survival rate and main success parameters were included for a qualitative and quantitative analysis (risk ratio and mean difference). RESULTS: In total, 43 studies with analysis of 4825 sockets were included. Compared with the noncompromised sockets, the compromised group showed no significant differences in implant survival rates (risk ratio=0.992; 95% confidence interval (CI)=0.979 to 1.005; P=.246). No significant statistical differences were found in marginal bone level at ≤12 months (mean difference [MD]=0.033; 95% CI=-0.012 to 0.078; P=.154) or esthetic parameters. CONCLUSIONS: Immediate implant placement in compromised sites does not appear to decrease the survival and success rates. However, randomized clinical trials with large sample sizes should be conducted to draw a definite conclusion about the efficacy and safety of this treatment protocol in compromised sockets.

Biological reactions of dental pulp stem cells cultured in presence of new xenograft bone substitutes from different sources: An in vitro study.

Aims: This study aimed to compare the biological reactions of dental pulp stem cells (DPSCs) cultured on new xenograft bone substitutes derived from camel and bovine bones. Materials and Methods: DPSCs were cultured and placed on different xenograft materials including Bone Plus (bovine), Camel Bone, and demineralized bovine bone matrix. The viability and proliferation of cells were evaluated by the methyl thiazolyl tetrazolium assay after 24, 48, and 72 h. The alkaline phosphatase (ALP) test and Alizarin red staining were performed at 7 and 21 days to assess the osteoblastic differentiation of cells. Osteocalcin (OCN) gene expression was evaluated qualitatively at 3-, 7- and 14-days using polymerase chain reaction (PCR). Semi-quantitative PCR was also performed using ImageJ software. Data were analyzed by ANOVA and Tukey's honestly significant difference test. Results: The cell proliferation rate was significantly different among the three xenograft bone substitutes at 24-, 48- and 72 h (P < 0.05). The ALP activity of DPSCs in all three xenograft bone substitute groups was greater than that in the control group (P < 0.05). Alizarin red staining showed no significant difference in the formation of calcified nodules among the groups. Qualitative and semi-quantitative PCR displayed that the expression of OCN gene in the Camel Bone and Bone Plus groups was higher than that in the demineralized bovine bone matrix group. Conclusions: The Camel Bone xenograft caused a high proliferation rate and optimal osteogenic differentiation of DPSCs qualitatively and semi-quantitatively in vitro. Further studies are required on this xenograft bone substitute.

A systematic scoring system to determine the long-term prognosis for severely damaged teeth.

Many of the criteria commonly considered in treatment planning for severely damaged teeth are well known to clinicians. However, a systematic approach to decision-making is lacking. The purpose of this article is to introduce a quantitative systematic risk assessment scoring system (RASS) to determine the long-term prognosis for severely damaged teeth based on several important factors. Before any treatment decision is made, the dentist should take into account the role of systemic parameters such as the medical condition of the patient, smoking status, psychological factors, patient expectations with regard to the duration and overall cost of treatment, and periodontal health. In the assessment of local factors, emphasis should be placed on 5 parameters: crown to root ratio, root condition, risk of furcation involvement, complexity of the final restoration, and esthetic results. In the proposed RASS, each of these parameters is ranked using 4 color-coded levels of risk: optimal (green), favorable (blue), unfavorable (yellow), or hopeless (red). The presence of even 1 parameter in the red zone is sufficient to consider tooth extraction. If no parameter is in the red zone, the final decision should be made after the possible effects of all of the clinical conditions are weighed and the overall risk of treatment failure is determined. Clinical decision-making with regard to the preservation or extraction of severely damaged teeth is a challenging, multifactorial process. The RASS introduced in this article focuses on 5 main factors to simplify and organize the decision-making process; however, many other parameters may affect the final treatment decision. Moreover, no decision-making system can be definitively applied to all clinical scenarios, and the entire process depends on the knowledge, experience, and expertise of the clinician.

CBCT Evaluation of the maxillary palatine process as a donor site for the regeneration of periodontal defects.

Background: The maxillary palatine process (MPP) is an excellent source of autogenous bone transplants for anterior maxillary reconstruction. This research aimed to determine the quantity and quality of accessible MPP as a donor location. Methods: Cone-beam computed tomography (CBCT) scans of patients referred to the School of Dentistry were evaluated by a certified examiner. The harvestable MPP was defined as the space between the distal surfaces of maxillary first premolars. OnDemand 3D Imaging software was used to determine bone properties. SPSS software was used to investigate the following variables: Bone characteristics are correlated with age and gender, accessible volume, and palatal width and height. P<0.05 was defined as the level of statistical significance. Results: This study was performed on CBCT scans of 81 subjects (41 females and 40 males). MPP volume and palatal heights were 1.33±0.53 cm3 and 20.86±5.51 mm, respectively. Maximum bone density was observed around lateral incisors. Palatal width was 33.81±2.42 mm between canines and 41.81±2.66 mm between premolars. The MPP volume was significantly greater in males (P<0.001). Additionally, there was a positive correlation between the volume and palatal width (P<0.05). Conclusion: Within the constraints of this research, there is a limited supply of MMP accessible for use as a graft source, and it is best suited for treating localized bone lesions. The favorable link between palatal breadth and harvestable volume aids the surgeon in estimating the quantity of bone accessible during the first evaluation.

A comparison of human dental pulp stem cell activity cultured on sandblasted titanium discs decontaminated with Er:YAG laser and air-powder abrasion: an in vitro study.

Decontamination of implant surfaces is important to the treatment of peri-implantitis. Er:YAG laser and air-powder abrasion system are regarded as the most effective means of decontamination of implant surfaces. The aim of this in vitro study was to compare the activity of human dental pulp stem cells (hDPSCs) cultured on decontaminated sandblasted titanium discs using Er:YAG laser irradiation and air-powder abrasion. Forty-five titanium discs were contaminated with Escherichia coli (E. coli) bacteria and fifteen titanium discs served as sterile control groups. Thirty contaminated titanium discs were decontaminated with Er:YAG laser or air-powder abrasion system and fifteen contaminated discs were used as contaminated control group. Afterwards, hDPSCs were seeded on all sixty experimental titanium discs. The effects of two decontamination tools on hDPSCs viability were evaluated by MTT assay. Alkaline phosphatase (ALP) activity assay, quantitative real-time PCR analysis and alizarin red staining method were performed to assess hDPSCs osteogenic differentiation. Scanning microscope electron (SEM) was also used to evaluate the effects of two different decontaminated methods on cellular morphology. Our study showed that decontamination using Er:YAG laser caused maximum cell viability. However, the ALP activity was not different in laser and air-abrasion groups. The significant expression of an osteoblastic marker and stronger Alizarin red staining were observed in laser irradiation groups. In addition, SEM observation indicated that grown cells were more stretched and more filopodia in Er:YAG-treated discs. In the present study, Er:YAG laser and air-powder abrasion improved the activity of the cells cultured on the decontaminated titanium discs. However, in comparison with air-powder abrasion, Er:YAG laser was more effective.

Effects of Two Protocols of Low-Level Laser Therapy on the Proliferation and Differentiation of Human Dental Pulp Stem Cells on Sandblasted Titanium Discs: An In Vitro Study.

Introduction: Stem cell activities have different effects on tissue response and its outcomes. Low-level laser therapy (LLLT) can be considered a trigger to modify stem cell activities. The objective of the present experimental investigation was to study the effects of two protocols of LLLT on the proliferation and differentiation of human dental pulp stem cells (hDPSCs) cultured on sandblasted titanium discs. Methods: Cells obtained from human dental pulp were seeded/cultured on titanium discs and were set in 2 main groups: (i) Radiated cells using the gallium-aluminium-arsenide (GaAlAs) diode laser at a continuous wavelength of 808 nm at 3 J/cm2 for 12 sec or 5 J/cm2 for 20 seconds, and (ii) Non-irradiated cells serving as control groups. The impact of LLLTs on hDPSC-proliferation and viability was investigated using the MTT assay after 24, 72 and 96 hours. The alkaline phosphatase activity was studied with p-nitrophenylphosphate after 14 and 28 days. The ability of hDPSCs to express osteocalcin was investigated using real-time polymerase chain reaction after 28 days, while their attachment was observed under a scanning electron microscope (SEM) after 14 and 28 days. Results: Our study showed that LLLTs caused maximum cell proliferation in 96 hours (P<0.001) with 3 J/cm2 resulting in a higher proliferation rate. The highest activity of alkaline phosphatase and osteocalcin expression was observed in the laser radiation groups after 28 days. Conclusion: The outcomes of the current study showed that cultured hDPSCs on sandblasted titanium discs had a tendency towards increased cellular activity in response to LLLTs. Thus, LLLTs could regulate the activities of hDPSCs on bone repair surrounding the sandblasted titanium discs.

The Role of Family and Friends in Accepting Dental Implant Treatment: A Preliminary Clinical Report on an Iranian Population.

OBJECTIVE: Consenting to a dental implant treatment plan may be a challenging decision for many patients, and they may prefer to consult their family and friends before making the final decision on this matter. The purpose of this preliminary report was to assess the role of family and friends, as the consultees, in consenting to a dental implant treatment plan by patients. MATERIALS AND METHODS: A total of 106 patients with dental implants were questioned about whether they made the final decision regarding their dental implant treatment by themselves or they consulted their family and friends prior to finalizing their decision. RESULTS: The majority of men (52.1%) reported making this decision by themselves and based on their own personal opinion, while most women (48.2%) reported making the decision after consulting their children. CONCLUSIONS: Within the limitations of this preliminary report, it appears that women are more willing to consult their children and friends on this matter compared with men. Also, men mostly consult their wives in making such a decision while women pay more attention to the opinion of their children in this respect.

Effect of Enamel Matrix Derivative and N-Acetyl Cysteine on Proliferation and Osteogenic Activity of Dental Pulp Stem Cells.

Successful bone regeneration often requires induction by signaling molecules. Enamel matrix derivative (EMD) is said to enhance initial phases of healing. N-acetyl cysteine (NAC) is a molecule assumed to enhance osteogenesis and induce osteoblastic differentiation. This study sought to compare effects of EMD and NAC on proliferation, mineralization, and enzymatic activity of dental pulp mesenchymal stem cells (DPSCs). DPSCs were cultured on mineralized bone allograft (MBA) powder. After 24 hours, EMD in concentrations of 10, 50, and 100 µg/mL and NAC in 5 mM concentration were added. Methyl thiazolyl tetrazolium (MTT) assay was used for cell proliferation assessment at 1, 2, and 3 days. Osteoblastic differentiation of DPSCs was evaluated at 30 days, by alizarin red staining and assessment of alkaline phosphatase (ALP) activity. Both EMD and NAC caused time-dependent reduction of cell proliferation compared with the negative control. Maximum proliferation of DPSCs was observed in the 10 µg/mL EMD group at all time points, whereas NAC caused higher ALP activity and mineralization of DPSCs compared with EMD. In vitro application of NAC, as a signaling molecule, may effectively enhance bone regeneration by the induction of mineralization and enzymatic activity, despite the resultant reduction in cell proliferation rate.

Clinical and Radiographic Outcomes of a Novel Transalveolar Sinus Floor Elevation Technique.

Objective: The aim of this study was to evaluate the clinical and radiographic outcomes of the "vertically expander screw" (VES) technique as a novel approach for maxillary sinus floor elevation and simultaneous implant placement. Materials and Methods: Forty-four patients (26 females, 18 males) received 71 implants with simultaneous transalveolar sinus floor elevation via the VES technique. The threaded bone expanders were used to elevate the sinus floor as well as bone expansion. The patients were followed-up on a regular basis, and final clinical and radiographic examinations were performed at least 24 months following functional loading. Statistical analysis was conducted using the Chi-square test, the correlation coefficient, and the independent t test (p < 0.05, 95% confidence interval). Results: All implants showed successful osseointegration. The mean marginal bone loss (MBL; 0.38 ± 0.75 mm) at the site of premolars was not significantly different from the value at the site of molars (0.17 ± 0.50 mm). The mean intrasinus bone gain (IBG) was not significantly different (3.47 ± 1.22 mm and 4.11 ± 1.67 mm, respectively; p = 0.92). Evaluation of implant success index (ISI) score revealed no difference between the premolars and molars (p = 0.12). Conclusion: Despite the limitations of the present study, it seems that the VES technique and simultaneous implant placement in carefully selected cases may result in promising outcomes. Clinical Relevance: Insufficient alveolar bone height and poor bone quality often complicate implant placement in the edentulous posterior maxilla. The VES technique and simultaneous implant placement can bring about favorable clinical and radiographic outcomes and high survival rate in carefully selected cases.

Interactive Effects of Five Dental Implant Design Parameters on the Peak Strains at the Interfacial Bone: A Finite Element Study.

PURPOSE: The aim of this study was to evaluate and compare the effect of changing five macrostructural design parameters of dental implants on the peak strains experienced by the interfacial bone. MATERIALS AND METHODS: Five geometric variables, including three body-related (implant length, diameter, and taper) and two thread-related (thread depth and thread angle) parameters, were defined. The alveolar bone was modeled as a block with anisotropic and linearly elastic properties with 20-mm height and 12-mm buccolingual and mesiodistal dimensions. Oblique occlusal loads (100-N vertical and 20-N horizontal) were applied to the abutment surface. A total of 162 models with different designs were defined by implementation of a full-factorial design. The peak values of the compressive and tensile principal strains in the cortical and cancellous bones were calculated by finite element analysis (FEA). RESULTS: Implant diameter and length had maximum and minimum effects on the peak compressive and tensile strains at the cortical interface, respectively. Implant diameter and thread depth had maximum and minimum effects on the maximum compressive strain at the cancellous interface, while thread angle and length had maximum and minimum significant effects on the maximum tensile strain at the cancellous interface. CONCLUSION: The interaction of thread parameters and taper has the greatest effect on the peak compressive and tensile strains at the cancellous interface and also on the peak tensile strain at the cortical interface, while body-related parameters are more effective on the peak compressive strain at the cortical interface.

Histological Evaluation of Bone Regeneration Using Hydroxyapatite Based Bone Substitute Derived from Antler: An Animal Study.

OBJECTIVE: Guided bone regeneration (GBR) is considered as a prerequisite in some cases of implant dentistry. For this purpose, bone materials are commonly used. Calcium compounds and Ca-P based materials like hydroxyapatite (HA, Ca10 (PO4)6(OH)2), due to their similarity with the human bone, can be used as graft materials for bone regeneration. This study aimed to evaluate biocompatibility of antler xenograft and compare the osteoconduction effects of antler xenograft with Cerabone in regeneration of calvarium bony defects of rabbits. METHODS AND MATERIALS: Five defects with a diameter of 6 mm and a depth of 3 mm were prepared in the calvarium of four rabbits. Thereafter, two defects were randomly grafted with antler xenograft, two defects were filled with Cerabone, and one defect remained as the untreated group. Histological evaluations, including measuring percentage of new regenerated bone and the amounts of osteoblast, osteoclast, and osteocyte cells, were also performed. To do statistical analyses, paired t-test, chi-square, and Fisher tests were applied. RESULTS: The percentage of new bone formation was significantly higher in antler xenograft (73.33%) and in Cerabone (48.91%) compared to the untreated group (18.91%). The amounts of osteocytes and osteoblasts were obtained as 3.52 ± 0.17 and 2.41 ± 0.24 in the Antler xenograft and as 2.57 ± 0.29 and 2.31 ± 0.32 in the Cerabone group, respectively. Bone marrow formation were significantly higher in antler xenograft (6.66 ± 5.34) and Cerabone (1.99 ± 3.17) compared to the untreated group. CONCLUSION: According to this pilot study, results of using antler xenograft as an osteoconductive materials in regeneration of rabbit calvarial defects are comparable with Cerabone. Although more clinical studies are needed.

Effect of Soft Tissue Condition on Peri-implant Health and Disease: A Retrospective Clinical Study.

This study retrospectively evaluated the effect of soft tissue condition on peri-implant health. Clinical variables (Plaque Index, keratinized tissue width, gingival biotype, and vestibular depth) were recorded. Probing depth, soft tissue recession, bleeding on probing, and radiographic marginal bone loss were assessed in relation to independent variables. Statistical analysis was performed using Mann-Whitney U test or Kruskal-Wallis rank test and a logistic regression model at the implant level. A total of 139 implants in 43 patients were assessed. Bleeding on probing was recorded at 54.7% sites, which was significantly related to the biofilm accumulation. Gender, history of periodontal disease, patient adherence to recall visits, and the presence of plaque were associated with higher peri-implant probing-depth values. The maximum soft tissue recession was recorded at sites with a thin biotype and shallow vestibular depth (P = .0). The logistic regression analysis revealed that plaque (P = .002) and vestibular depth (P = .043) were significantly associated with peri-implantitis. Within the study limitations, patients with high plaque accumulation and shallow vestibular depth are more prone to peri-implant disease.

Average and Maximum Papilla Heights around Dental Implants in the Anterior Maxillary Region: A Retrospective Clinical Study.

OBJECTIVE: The aim of this study was to determine the average and maximum height of the papilla around maxillary anterior implants in respect of neighboring structures and location of implants. MATERIALS AND METHODS: 92 dental implants from 63 patients were investigated in this study. Those implants were placed in the anterior maxillary region and had been loaded for a minimum of one year. After receiving written consent, clinical data including the height of interproximal papillae adjacent to the tooth/implant/pontic were obtained through clinical observation. The independent t-test or ANOVA, the regression modeling, and generalized estimating equation (GEE) models were used for statistical analysis (p < 0.05). RESULTS: Papilla height was calculated as 2.8 mm (1-5.5 mm) for implant-tooth sites, 2.6 mm (1-4 mm) in implants beside pontics, and 2.5 mm (1-3.5 mm) for implants adjacent to implants. Despite the lack of a significant difference in the mean papilla height in the studied groups, the maximum values of papilla heights were significantly different. CONCLUSIONS: In this study, no significant differences were found in papilla height mean values in relation to neighboring structures or location of implants in the anterior maxilla. However, the maximum values of papilla heights were observed around implants next to natural teeth.