Introduction

The posterior edentulous maxilla is most usually complemented by reduced bone density and height. The configuration of dental implants has improved the recovery of the edentate posterior maxilla with a fixed prosthesis. A significant need for insert location is the proximity of a substantial bone and the quality of the residual bone (Bernardello et al., 2011). The treatment of insufficient maxillary alveolar ridge is attempted due to pneumatization of the maxillary sinus in the posterior maxillary area with impaired alveolar bone height.

Bone volume can also be increased by extension while growing vertical bone calculation is a delicate process. The growth of sinus layer is also an option for expanding vertical bone height (Bernardello et al., 2015). Any extensive knowledge of modern expansion systems assisted by good patient choice will lead to convincing long-haul strategies for the management of deficient posterior maxilla. There are different methods for enlarging maxillary sinus. They can indeed be comprehensively divided into two separate methods for sinus floor height: a) Lateral antrostomy as a step-by-step approach as either an immediate technique. (b) a technique for osteotomy with a crestal approach mostly as a roundabout tool (Cosci & Luccioli, 2000).

Transcrestal approach is seen as the most traditionalist method and has a few desirable circumstances in comparison to horizontal osteotomy. The osteotome method involves the establishment of implant bed without ostectomy to allow longer and larger inserts to occur, especially in posterior maxillary jaw (Spinato, Bernardello, Sassatelli, & Zaffe, 2017). In endosseous implant therapy, the sinus grows. This technique helps to increase the thickness as well as the volume of spongy bone in apico-coronal and buccal-lingual dimensions by pressure conceivable from its viscoelastic properties. The use of osteotomes comprehends for bone compaction, cortical sinus floor elevation and edge expansion described in various clinical studies (Cosci & Luccioli, 2000; Fairbairn & Leventis, 2015).

Minimum alveolar bone height suggested for osteotome method for transcrestal sinus lift being 5 mm, although implant placement is advised when the preliminary alveolar bone height is at minimum 5 to 7 mm. An average increase of 3 to 3.25 mm in alveolar height through osteotome combined both with bone add-on technique has been recorded (Rapani & Rapani, 2012). The purpose of our research was, therefore, to assess retrospectively the amount of bone height acquired through a transcrestal approach to sinus elevation using osteotomes.

Materials and Methods

A total of 42 partially edentulous patients in the posterior maxilla were short-listed. Of these patients, 35 patients were identified as cases indicated for indirect sinus lift and the remaining 7 cases were indicated to undergo direct sinus lift. 45 implants were placed in these 35 patients. The average follow-up time was 6-12 months. The patients were primarily evaluated with a CBCT prior to implant placement to gauge the bone dimensions. The implants placed were placed in the first, second molar position and in second premolar position accordingly with the values recorded in Table 1. After six months follow up, a CBCT was again taken to evaluate the bone height gained.

Results

The preoperative and postoperative values of the bone height were noted in the region of the implant placement. All the implants used were 4.3 mm in diameter and 10.5, 11or 13mm in length. The cumulative survival rate of the implants was 97.78 Of 45 implants in operation, 1 was lost after loading due to acute infection over 24 days. Almost no adverse effects were observed. The mean bone height estimated from the alveolar crest to the base of the implant at the period of implant placement was 6.79 mm ± 1.35 mm. The mean estimated bone height at the six-month follow-up time was 11.4 mm ±0.88 mm, which was very significant (p < 0.05) Table 1.

Discussion

The sinus increase treatment has been shown to be an effective and often necessary technique for rehabilitating maxillary atrophic ridge with pneumatic sinuses. The lateral approach suggested by Boyne and James since 1980 permitted a dramatic improvement in bone > 10 mm, in atrophic ridges, but resulted in significantly higher post-surgery morbidity and a higher likelihood for membrane perforation (Cha, Kim, Nowzari, Chang, & Ahn, 2014; Rapani & Rapani, 2012).

In 1986, Tatum Jr. suggested a transcrestal, rather traditional conservative approach, later modified by Summers, which originally portrayed the use of osteotomes to raise the film and eliminate the banging, making the technique more relaxed. Nowadays, the crest approach is a strong technique that allows for appropriate incorporation with high endurance levels. Crestal method, osteotome interfered sinus lift surgical technique, can be done with a variety of bone junction material, e.g. allograft, autogenous bone or heterologous materials, and platelet derivatives themselves or in conjunction with unifying materials, in order to combine the properties of the production factor to just the mechanical proximity of the delicate platelet derivatives that enables super-plasticity (Mazor, Peleg, Garg, & Luboshitz, 2004). The key containment of this technique was, however, the considerable stature of > 5 mm of remaining bone height due to the danger of layer perforation and low embed solidity. In the latest evaluation report, 45 inserts inserted in a standard 6.79 mm peak showed superb durability levels (97.78 per cent) in the corresponding duration.

The negligible height of the maxillary sinus membrane and the synchronous configuration of the implants give rise to bone growth and osseointegration. Measurement of bone growth does not continue to differ when performing sinus film heights with or without bone grafts (Soardi, Zaffe, Motroni, & Wang, 2014). Success has also been defined by various authors and in case of a combination of osteotome sinus upsurge and joint material was shown to be effective. Postoperative CT images showed tent-like bone formation all around implants. This indicates that a tent-like image is stretched from the apical implant surface by sinus membrane, and also that bone tissue formation is acquired in the space produced by sinus membrane tent.

Consequently, in order to accomplish bone formation only at the top of both the implant, it is necessary to find techniques that allow the membrane to remain elevated in its new role using membrane elevation technique. The implant inserted during the sinus lift may also serve as an object to keep the sinus membrane at an elevated location, as in this research, where no graft material has been used. Rather, the implant has only been used to stimulate the sinus membrane.

Nedir et al. registered sinus floor elevation without grafting materials to demonstrate a bone deficiency in the implant extremity after 1 year with 2.5 mm bone benefit (Nedir, Bischof, Vazquez, Szmukler-Moncler, & Bernard, 2006). Nevertheless, avoiding the use of graft material not only removes the need for secondary surgery but also decreases the risk of infection, the possibility of overfilling maxillary sinus or membranes necrosis and sinusitis (Nedir et al., 2012) is also avoided. No graft material inserted in the newly developed region below the Schneider membrane has been reported by numerous authors (Lai, Zhang, Wang, Zhuang, & Liu, 2008). However, studies documenting the use of osteotomes for indirect sinus lifts with no graft material in place are uncommon sites. The results of the study verified the use of implants as tenting screws to hold the sinus membrane at the desired position. Radiographically, peri implant radiopacity confirmed bone formation around the implant surface and apex (He, Chang, & Liu, 2013).

Conclusion

This research concluded the promising results of transcrestal osteotomy with implants utilized for tenting the sinus membrane, in obtaining a substantial average bone height increase of 4.6 mm. This will enable the clinicians to implement this procedure in surgical reconstruction and rehabilitation of patients with implants in those regions with insufficient bone due to excessive pneumatization of the maxillary sinus.

Funding Support

The authors declare that they have no funding support for this study.

Conflict of Interest

The authors declare that they have no conflict of interest for this study.