An in vitro comparative evaluation between virtually planned implant positions on interactive implant software versus actual implant positions achieved using sterolithographic open guide system.

PURPOSE: To evaluate and compare the positional and angular accuracy of virtual implant positions planned on cone-beam computed tomography and final implant positions achieved using a universal open guide system. MATERIALS AND METHODS: A dual scan of a partially edentulous jaw model along with prosthesis was done, and virtual implant planning was performed. Three implant positions in relation to 35, 36, and 37 were simulated (Group A). In total, 24 implants were placed in eight replaceable bone blocks (Group B) in the same region on the model using an open stereolithographic template. The linear positions and angulation of the placed implants were determined using Vision Measuring Machine. Deviations between virtually planned and surgically placed implants were analyzed in terms of linear and angular measurements. Data were analyzed with the independent-sample t-test with differences P ≤ 0.05 being considered statistically significant. RESULTS: The linear distance (mean ± standard deviation [SD]) in mesiodistal direction between implants in relation to 35 and 36, 36 and 37, 35 and 37 in Group A was 8.79 ± 0 mm, 8.71 ± 0 mm, and 17.50 ± 0 mm, respectively, and in Group B was 7.70 ± 0.58 mm, 8.11 ± 0.30 mm, and 15.80 ± 0.48 mm. All these above values were found to be statistically significant (P ≤ 0.05). The linear distance (mean ± SD) in the vertical direction (mesial) for implants placed in the region of 35, 36, 37 for Group A was 1.51 ± 0 mm, 1.51 ± 0 mm, and 2.47 ± 0 mm, respectively, and for Group B was 1.37 ± 0.32 mm, 1.65 ± 0.48 mm, and 1.79 ± 0.36 mm, respectively. The linear distance (mean ± SD) in the vertical direction (distal) for implants placed in the region of 35, 36, 37 for Group A was 3.37 ± 0 mm, 1.51 ± 0 mm, and 1.51 ± 0 mm, respectively, and for Group B was 1.86 ± 0.48 mm (P ≤ 0.05), 1.56 ± 0.23 mm, and 1.29 ± 0.39 mm (P ≤ 0.05), respectively. The angular deviation (perpendicularity) values for virtually planned implants (Group A) were 90.00° ± 0° and for implants placed in the region of 35, 36, and 37 (Group B) were 84.52° ± 5.4°, 83.57° ± 1.52°, and 80.41° ± 2.37°, respectively, which are highly significant (P ≤ 0.05). CONCLUSIONS: The stereolithographic universal open guide used in the study may be considered accurate for placement of implants in mesiodistal position and also in terms of perpendicularity but not in the vertical position. Stereolithographic open guide may be recommended for more accurate implant position, especially for the placement of multiple implants.

A bar and ball attachment prosthesis over osseointegrated implants post mandibular resection.

Rehabilitation of mandibular resection poses functional, esthetic, and psychological challenges. The deviation and rotation of the mandible toward the resected side leaves the patient with almost no option of chewing. This is aggravated if the patient is edentulous. The case report discussed in this article was an edentulous patient taken up with the primary goal to limit deviation toward resected side and provide a stable and retentive prosthesis to the patient. Two implants were placed anteriorly, splinted with bar and clip supported superstructure. The splinted implants with bar and clip superstructure provided the mandibular prosthesis with retention and some support. A posterior implant was also placed in the region of mandibular first molar on the left side for added support. This provided with a tripod configuration and limited the prosthetic movement of the mandibular prosthesis. This case report highlights an alternate way toward the rehabilitation of edentulous mandible post mandibular resection when surgical reconstruction may not be feasible.

Classification system on the selection of number of implants and superstructure design on the basis available vertical restorative space and interforaminal distance for implant supported mandibular overdenture.

PURPOSE: The rehabilitation of the edentulous mandible is a challenge due to various limiting factors, of which the available vertical restorative space (AVRS) has been well understood in the literature. However, other anatomic variations such as arch form, arch size, and also the interforaminal distance (IFD) (due to the presence of mandibular nerve) are influential in the selection of size and position of implants, and thereby the prosthetic design. MATERIALS AND METHOD: In the present study, 30 edentulous patients from a group of 300 edentulous patients, representing all the three jaw relations (Class I, II, and III) were evaluated for designing a classification that could help in a comprehensive treatment plan for the edentulous mandible. Dental panoramic radiographs of each individual with a trial or final prosthesis were made. The horizontal IFD and AVRS values were calculated. RESULTS: One-way analysis of variance followed by post-hoc test (multiple comparison) and Bonferroni method having P < 0.05 as significant value showed an overall mean of 38.9 mm for horizontal distance and 13.69 mm for the AVRS in 30 edentulous patients. CONCLUSION: The results showed that in the majority of cases (90%) there is insufficient space to place a bar attachment supported by five implants for mandibular overdentures. This suggests that a universal treatment plan cannot be followed due to varying anatomic factors. Hence, it becomes imperative to have a set of clinical guidelines based on the AVRS and IFD, for the selection of implant number and type of attachment. The article proposes a simple classification system based on the AVRS and IFD for establishing guidelines in the treatment planning of the edentulous mandible, to aid in selection of implant size, number, and position along with the associated prosthetic design.

A comparative evaluation of platelet-rich plasma in combination with demineralized freeze-dried bone allograft and DFDBA alone in the treatment of periodontal intrabony defects: A clinicoradiographic study.

BACKGROUND: The aim of the present clinical trial was to compare PRP combined with a DFDBA to DFDBA mixed with a normal saline solution in the treatment of human intrabony defects. MATERIALS AND METHODS: Twenty interproximal intrabony osseous defects in twenty non-smoking, healthy subjects diagnosed with chronic periodontitis were treated in this study. Ten subjects each were randomly assigned to the test group (PRP + DFDBA) or the control group (DFDBA + saline). Clinical and radiographic measurements were made at baseline, three month and at six-month evaluation. RESULTS: The results at three and six months, when compared to the baseline, indicated that both treatment modalities resulted in significant changes in all clinical parameters (gingival index, bleeding on probing, probing depth, clinical attachment level and gingival recession; P < 0.01) and radiographic parameters (hard-tissue fill and bone-depth reduction; P < 0.01). However, the test group exhibited statistically significantly greater changes compared to the control group in plaque index at three months (P = 0.00), probing depth reduction at 6 months (P = 0.02) and the radiographic defect fill at 6 months (P = 0.01). CONCLUSIONS: Treatment with a combination of PRP and DFDBA led to a statistically significantly greater improvement in plaque index at 3 months, probing depth at 6 months and radiographic defect fill at 6 months in intrabony periodontal defects as compared to DFDBA with normal saline.