Potentials of pure xenograft materials in maxillary ridge augmentation: A case series.

Many patients require edentulous ridge augmentation for dental implant placement. The main objective of this study was to evaluate the results of maxillary edentulous ridge augmentation exclusively with xenograft materials with and without simultaneous sinus floor elevation. This study reports the data retrieved from the records of 16 patients. The treatment outcome was assessed at least 6 months, postoperatively. Paired samples t-test or Wilcoxon Signed Rank test was used to compare the pre-and postoperative ridge dimensions. Dental implants were placed simultaneously in 7 patients, while 9 patients underwent delayed implant placement. In total, 68 implants were placed, and 12 patients also underwent maxillary sinus floor augmentation. A significant bone gain was achieved in both horizontal and vertical dimensions of edentulous maxillary ridges (P < 0.001). Ridge width increased by an average of 4.35 ± 1.90 mm (95% CI: 3.84 to 4.85 mm) while ridge height in areas of sinus floor augmentation increased by 8.19 ± 2.91 mm (95% CI: 7.33 to 9.05 mm). Within the study limitations, it appears that maxillary ridge augmentation according to the guided bone regeneration (GBR) protocols with exclusive use of xenograft particulate materials can provide optimal bone quantity for dental implant placement.

Immediate vs. delayed endosseous integration of maxi implants: a torque removal animal study.

Background. Delayed loading is one of the concerns in implant patients. Immediate loading can solve the problem and make patients more satisfied. The present study aimed to compare the removal torque of maxi implants under different loading (immediate and delayed) patterns. Methods. This split-mouth experimental study included 2 dogs. Impressions were made and then all the premolars were extracted under general anesthesia. After a three-month healing period, 3 implants were inserted in each quadrant (a total of 12 implants). Anterior and posterior implants (the case group) were splinted by an acrylic temporary bridge in order to make the middle implants (the control group) off the occlusion. The dogs were sacrificed after 6 weeks and bone blocks were submitted for removal torque test. Data were analyzed with ANOVA (P<0.05). Results. Mean torque values for the cases and control groups were 46.82±25.58 and 59.88±15.19, respectively (P=0.582; not significant). Conclusion. It may be concluded that immediate loading does not reduce the reverse torque values of maxi implants. This supports the advantages of immediate loading for maxi implants.

Analysis of human leukocyte antigen class II gene polymorphism in Iranian patients with Papillon-Lefevre syndrome: a family study.

BACKGROUND: Papillon-Lefevre syndrome (PLS) is a rare autosomal recessive disorder characterized by palmoplantar hyperkeratosis and early development of aggressive periodontitis. Although cathepsin C (CTSC) gene mutations have been established in about 70-80% of PLS patients, it is assumed that the patients may have dysfunctioning of immune defense mechanisms. OBJECTIVE: To assess the association of HLA class II genes and PLS. METHODS: HLA class II genes were typed in nine Iranian PLS patients and their family members and the results were compared to 816 Iranian healthy subjects. RESULTS: The results of this study revealed that DRB1*0101 and DRB1*0301 alleles were more frequent in PLS patients than in normal controls. However, there was no significant difference between PLS patients and normal controls. Moreover, the same haplotypes and genotype combinations were also observed in some patients and their healthy siblings. CONCLUSION: The results of this study showed no strong association between HLA class II alleles and PLS.

HLA class I gene polymorphism in Iranian patients with Papillon-Lefevre Syndrome.

BACKGROUND: Papillon-Lefevre Syndrome (PLS) is a rare autosomal recessive disorder characterized by diffused palmoplantar keratoderma and severe periodontitis. Increased susceptibility to infections due to impairment of the immune system is considered to be involved in pathoetiology of this disease. OBJECTIVES: According to the crucial function of HLA molecules in immune responses and association between certain HLA class I alleles and some periodontal or skin diseases, this study was designed to evaluate the relation of HLA class I genes and PLS. METHODS: HLA class I genes were typed by PCR-SSP (Polymerase Chain Reaction with Sequence Specific Primers) method in eight Iranian PLS patients and 89 healthy controls. RESULTS: The results showed no significant difference between the patients and controls. Moreover, identical haplotypes or genotypes were also observed among PLS patients and their healthy siblings. CONCLUSIONS: It seems that further genes are involved in genetic susceptibility to PLS. However the results of this study showed no significant association between HLA class I genes and PLS, molecular analyses of killer immunoglobulin-like receptors (KIRs) and MHC class I chain-related gene A and B (MICA/B) in PLS may clear many obscure points about the genetic factors involved in these diseases.