The aim of this study was evaluating the clinical effectiveness of the hand instrument in conjunction with sectional matrix when applying lateral forces at the contact area during curing to achieve large and tight proximal contacts in posterior teeth.

Dental caries is considered as one of the most prevalent oral infections. Initiation of dental caries is a mufti-factorial process, its risk factors includes high loads of cariogenic bacteria, increased frequency of sugar intake, insufficient exposure to fluoride and reduced salivary flow. Other factors that may influence the occurrence of caries include poor oral hygiene and socio-economic status.

Inter-proximal caries lesions develop between the contacting proximal surfaces of two adjacent teeth. Massive evolution took place in restorative techniques, composite resin materials, cavity designs and armamentarium in the past few decades. As well as drastic solutions for earlier problems of composite resins such as bonding to dentin, wear resistance, postoperative sensitivity and polymerization shrinkage. Despite all the progress noted in that area, still achieving proximal contact tightness in Class II resin composite restorations is considered one of the biggest challenges facing clinicians Proximal contact tightness is a physiological dynamic entity of multifactorial origin that is largely affected by tooth type, location, time of day, patient position, mastication and restorative procedures Failure to obtain proper proximal contact area will influence stability of dental arch and transmission of forces along long axis of teeth during mastication. Traumatic masticatory forces can lead to various problems like; rotation and displacement of the teeth, lifting forces on the teeth, deflective occlusal contacts and food impactions that would result in trauma, pain, inflammation and bleeding of the periodontium. The contact must be neither open nor too tight.

Aim of this study was evaluating the clinical effectiveness of the Optra Contact in conjunction with sectional matrix when applying lateral forces at the contact area during curing to achieve large and tight proximal contacts in posterior teeth.

Inclusion Criteria:

• Patients having posterior class II carious lesions were included
• Absence of pain from the tooth to be restored
• Good general health
• Age range:18-50 years
• Fully erupted occluding teeth

Exclusion Criteria:

• Diastema between posterior teeth
• Presence of fixed partial dentures
• Severe periodontal diseases Tooth mobility Non vital teeth